[{"awards": "1440435 Ducklow, Hugh; 0636696 DeVries, Arthur; 1142158 Cheng, Chi-Hing; None TBD; 1543383 Postlethwait, John; 2224611 Schofield, Oscar; 1344502 Ducklow, Hugh; 2026045 Schofield, Oscar", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 11 Mar 2025 00:00:00 GMT", "description": "Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. Since its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public\u0027s fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth\u0027s last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Cryonotothenioid; R/V LMG; Bellingshausen Sea; Southern Ocean; Notothenioid; FISHERIES", "locations": "Bellingshausen Sea; Southern Ocean; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Corso, Andrew; Desvignes, Thomas; McDowell, Jan; Cheng, Chi-Hing; Biesack, Ellen; Steinberg, Deborah; Hilton, Eric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repositories": null, "science_programs": "LTER", "south": -90.0, "title": "LTER Palmer, Antarctica (PAL): Land-Shelf-Ocean Connectivity, Ecosystem Resilience and Transformation in a Sea-Ice Influenced Pelagic Ecosystem", "uid": "p0010494", "west": -180.0}, {"awards": "2332062 Kim, Heather", "bounds_geometry": "POLYGON((-80 -59,-76.8 -59,-73.6 -59,-70.4 -59,-67.2 -59,-64 -59,-60.8 -59,-57.599999999999994 -59,-54.4 -59,-51.2 -59,-48 -59,-48 -60.6,-48 -62.2,-48 -63.8,-48 -65.4,-48 -67,-48 -68.6,-48 -70.2,-48 -71.8,-48 -73.4,-48 -75,-51.2 -75,-54.4 -75,-57.6 -75,-60.8 -75,-64 -75,-67.2 -75,-70.4 -75,-73.6 -75,-76.8 -75,-80 -75,-80 -73.4,-80 -71.8,-80 -70.2,-80 -68.6,-80 -67,-80 -65.4,-80 -63.8,-80 -62.2,-80 -60.6,-80 -59))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Aug 2024 00:00:00 GMT", "description": "The West Antarctic Peninsula (WAP) is experiencing significant environmental changes, including warming temperatures, reduced sea ice, and glacier retreat. These changes could impact marine ecosystems and biological and chemical processes, particularly the biological pump, which is the process by which carbon is transported from the ocean surface to the deep sea, playing a crucial role in regulating atmospheric carbon dioxide levels. This project aims to understand how climate change affects the biological pump in the WAP region. Using a combination of advanced modeling techniques and data from long-term research programs, the project will investigate the processes governing the biological pump and its climate feedback. The findings will provide insights into the future dynamics of the WAP region and contribute to our understanding of climate change impacts on polar marine ecosystems. This research is important as it will enhance knowledge of how polar regions respond to climate change, which is vital for predicting global climate patterns and informing conservation efforts. Furthermore, the project supports the development of early-career researchers and promotes diversity in science through collaborations with educational programs and outreach to underrepresented communities. This project focuses on the WAP, a region undergoing rapid environmental changes. The goal is to investigate and quantify the factors controlling the biological pump and its feedback to climate change and variability. A novel hybrid modeling framework will be developed, integrating observational data from the Palmer Long-Term Ecological Research program and the Rothera Oceanographic and Biological Time-Series into a sophisticated one-dimensional mechanistic biogeochemical model. This framework will utilize Artificial Intelligence and Machine Learning techniques for data assimilation and parameter optimization. By incorporating complementary datasets and optimizing model parameters, the project aims to reduce uncertainties in modeling biological pump processes. The study will also use climate scenarios from the Coupled Model Intercomparison Project Phase 6 to assess the impacts of future climate conditions on the biological pump. Additionally, the project will examine the role of vertical mixing of dissolved organic matter in total export production, providing a comprehensive understanding of the WAP carbon cycle. The outcomes will improve temporal resolution and data assimilation, advancing the mechanistic understanding of the interplay between ocean dynamics and biogeochemical processes in the changing polar environment. The project will also leverage unique datasets and make the model framework and source codes publicly available, facilitating collaboration and benefiting the broader scientific community. Outreach efforts include engaging with educational programs and promoting diversity in Polar Science through collaborations with institutions serving underrepresented groups. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -48.0, "geometry": "POINT(-64 -67)", "instruments": null, "is_usap_dc": true, "keywords": "West Antarctic; BIOGEOCHEMICAL CYCLES; PELAGIC; ECOSYSTEM FUNCTIONS", "locations": "West Antarctic", "north": -59.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kim, Heather", "platforms": null, "repositories": null, "science_programs": null, "south": -75.0, "title": "Projecting the Biological Carbon Pump and Climate Feedback in the Rapidly Changing West Antarctic Peninsula: A Hybrid Modeling Study", "uid": "p0010474", "west": -80.0}, {"awards": "0087144 Conway, Howard", "bounds_geometry": "POLYGON((-150 -83.5,-148 -83.5,-146 -83.5,-144 -83.5,-142 -83.5,-140 -83.5,-138 -83.5,-136 -83.5,-134 -83.5,-132 -83.5,-130 -83.5,-130 -83.65,-130 -83.8,-130 -83.95,-130 -84.1,-130 -84.25,-130 -84.4,-130 -84.55,-130 -84.7,-130 -84.85,-130 -85,-132 -85,-134 -85,-136 -85,-138 -85,-140 -85,-142 -85,-144 -85,-146 -85,-148 -85,-150 -85,-150 -84.85,-150 -84.7,-150 -84.55,-150 -84.4,-150 -84.25,-150 -84.1,-150 -83.95,-150 -83.8,-150 -83.65,-150 -83.5))", "dataset_titles": "Impulse HF radar data from Conway Ridge", "datasets": [{"dataset_uid": "601810", "doi": "10.15784/601810", "keywords": "Antarctica; Cryosphere; Siple Coast", "people": "Conway, Howard; Christianson, Knut; Hoffman, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Impulse HF radar data from Conway Ridge", "url": "https://www.usap-dc.org/view/dataset/601810"}], "date_created": "Mon, 22 Jul 2024 00:00:00 GMT", "description": "Marine ice sheets are low-pass filters of climate variability that take centuries to adjust to interior and near-terminus changes in mass balance. Constraining these century-scale changes from satellite observations that span only the last 40 years is challenging. Here, we take a different approach of carefully synthesizing different data sets to infer changes in the configurations of van der Veen and Mercer Ice Streams on the Siple Coast over the past 3000 years from englacial features encoded in ice-penetrating radar data. Englacial radar data from Conway Ridge reveal smooth, surface conformal layers overlying disrupted stratigraphy that suggest the van der Veen Ice Stream was 40 km wider over 3000 years ago. Englacial layer dating indicates that the ice stream narrowed to its present configuration between $\\sim3000$ and $\\sim1000$ years ago. Similarly disrupted stratigraphy and buried crevasses suggest that ice flowing from Mercer to Whillans Ice Stream across the northwestern tip of the ridge slowed shortly after. Using an ice-flow model capable of simulating shear margin migration, we evaluate whether small changes in ice thickness can lead to large changes in shear margin location. Our results suggest that the tip of Conway Ridge is sensitive to thinning and thickening, and that when the basal strength at the tip of the ridge increases with the height above flotation, the ice sheet shear margins can change quickly.", "east": -130.0, "geometry": "POINT(-140 -84.25)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER ELEVATION/ICE SHEET ELEVATION; Siple Coast", "locations": "Siple Coast", "north": -83.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hoffman, Andrew; Conway, Howard", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Glacial History of Ridge AB, West Antarctica", "uid": "p0010470", "west": -150.0}, {"awards": "2336354 Juarez Rivera, Marisol", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": "Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae", "datasets": [{"dataset_uid": "601839", "doi": "10.15784/601839", "keywords": "Antarctica; Cryosphere; Dry Valleys; Lake Fryxell; Laminae; Microbial Mat; Thickness", "people": "Sumner, Dawn; Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian; Paul, Ann", "repository": "USAP-DC", "science_program": null, "title": "Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae", "url": "https://www.usap-dc.org/view/dataset/601839"}], "date_created": "Fri, 05 Jul 2024 00:00:00 GMT", "description": "Perennially ice-covered lakes in the McMurdo Dry Valleys of Antarctica contain abundant microbial mats, and the export of this mat material can fertilize the surrounding polar desert ecosystems. These desert soils are one of the most organic-poor on earth yet host a community of microorganisms. Microbial mat material is exported from the shallow, gas-supersaturated regions of the lakes when gas bubbles form in the mats, lifting them to the ice cover; the perennial ice cover maintains gas supersaturation. These mats freeze in and are exported to the surrounding soils through ice ablation. The largest seasonal decrease and thinnest ice cover in the history of Lake Fryxell was recorded during the 2022-2023 Austral summer. In this thin ice year, the water column dissolved oxygen increased over prior observations, and the lake bottom surface area with bubble-disrupted mat was more than double that observed in 1980-1981 and 2006-2007. This work will constrain mat mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning to understand how future changing regional climate and predicted seasonal loss of lake ice cover will affect nutrient transport in the McMurdo Dry Valleys. Exceptional years of mat export are hypothesized to have the most significant impact on nutrient export to soil communities; variability in mat liftoff may thus play a role in the McMurdo Dry Valleys ecosystem response to changing climate. The perennial ice cover of lakes in the McMurdo Dry Valleys of Antarctica modulates the transfer of gasses, organic and inorganic material, between the lakes and surrounding soils. The export of biomass in these lakes is driven by the supersaturation of atmospheric gasses in the shallow regions under perennial ice cover. Gas bubbles nucleate in the mats, producing buoyancy that lifts them to the bottom of the ice, where they freeze in and are exported to the surrounding soils through ice ablation. These mats represent a significant source of biomass and nutrients to the McMurdo Dry Valleys soils, which are among the most organic-poor on earth. Nevertheless, this biomass remains unaccounted for in organic carbon cycling models for the McMurdo Dry Valleys. Ice cover data from the McMurdo Dry Valleys Long Term Ecological Research Project shows that the ice thickness has undergone cyclical variation over the last 40 years, reaching the largest seasonal decrease and thinnest ice-cover in the recorded history of Lake Fryxell during the 2022-2023 austral summer. Preliminary work shows that the surface area with mat liftoff at Lake Fryxell is more than double that observed in 1980-1981 and 2006-2007, coinciding with this unprecedented thinning of the ice-cover and an increase in the water column dissolved O2. This research will constrain biomass mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning. The researchers hypothesize that a thinner ice cover promotes more biomass mobilization by 1) stimulating additional production of gas bubbles from the existing gas-supersaturated waters during summertime photosynthesis to create microbial mat liftoff and 2) promoting mat liftoff in deeper, thicker microbial mats, and 3) that this biomass can be traced into the soils by characterizing its chemistry and modeling the most likely depositional settings. This work will use microbial mat samples, lake dissolved oxygen and photosynthetically active radiation data and underwater drone footage documenting the depth distribution of liftoff mats in January 2023, and long-term ice cover thickness, photosynthetically active radiation, and lake level change data collected by the McMurdo Dry Valleys Long Term Ecological Research Project to test hypotheses 1-3. The dispersal of the liftoff mat exposed at Lake Fryxell surface will be modeled using a Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Exceptional liftoff years like the present are hypothesized to have the most significant impact on the soil communities as the rates of soil respiration increase with the addition of carbon. However, continued warming in the next 10 - 40 years may result in seasonal loss of the ice cover and cessation of liftoff mat export. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Stable Isotopes; MINERALS; LAKE/POND; ISOTOPES; Organic Matter; McMurdo Dry Valleys; SEDIMENTARY ROCKS", "locations": "McMurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Earth Sciences", "paleo_time": null, "persons": "Juarez Rivera, Marisol", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?", "uid": "p0010467", "west": 160.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 12 Feb 2024 00:00:00 GMT", "description": "Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function.\u003cbr/\u003e \u003cbr/\u003e \u003cbr/\u003eTo understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; BENTHIC; PENGUINS; FLUORESCENCE; PHYTOPLANKTON", "locations": "Palmer Station", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": null, "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots", "uid": "p0010448", "west": null}, {"awards": "1744989 LaRue, Michelle", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Detecting climate signals in populations: case of emperor penguin; Emperor penguin population trends (2009-2018); Landfast ice: a major driver of reproductive success in a polar seabird", "datasets": [{"dataset_uid": "200410", "doi": "10.5061/dryad.m63xsj48v", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Emperor penguin population trends (2009-2018)", "url": "https://doi.org/10.5061/dryad.m63xsj48v"}, {"dataset_uid": "601513", "doi": "10.15784/601513", "keywords": "Antarctica; Breeding Success; Emperor Penguin; Fast Sea Ice", "people": "Jenouvrier, Stephanie; Labrousse, Sara", "repository": "USAP-DC", "science_program": null, "title": "Landfast ice: a major driver of reproductive success in a polar seabird", "url": "https://www.usap-dc.org/view/dataset/601513"}, {"dataset_uid": "601491", "doi": "10.15784/601491", "keywords": "Antarctica", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Detecting climate signals in populations: case of emperor penguin", "url": "https://www.usap-dc.org/view/dataset/601491"}], "date_created": "Thu, 08 Feb 2024 00:00:00 GMT", "description": "This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys - these results have been uploaded to MAPPPD (penguinmap.com) and are freely available for use. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "COMMUNITY DYNAMICS; USA/NSF; Amd/Us; USAP-DC; Antarctica; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Ito, Emi; Jenouvrier, Stephanie", "platforms": null, "repo": "Dryad", "repositories": "Dryad; USAP-DC", "science_programs": null, "south": -90.0, "title": "A Multi-scale Approach to Understanding Spatial and Population Variability in Emperor Penguins", "uid": "p0010447", "west": -180.0}, {"awards": "2224760 Gooseff, Michael", "bounds_geometry": "POINT(162.87 -77)", "dataset_titles": "EDI Data Portal: McMurdo Dry Valleys LTER", "datasets": [{"dataset_uid": "200379", "doi": "", "keywords": null, "people": null, "repository": "Environmental Data Initiative (EDI)", "science_program": null, "title": "EDI Data Portal: McMurdo Dry Valleys LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM"}], "date_created": "Tue, 14 Nov 2023 00:00:00 GMT", "description": "Non-technical Abstract The McMurdo Dry Valleys LTER seeks to understand how changes in the temporal variability of ecological connectivity interact with existing landscape legacies to alter the structure and functioning of this extreme polar desert ecosystem. This research has broad implications, as it will help us to understand how natural ecosystems respond to ongoing anthropogenic global change. At the same time, this project also serves an important educational and outreach function, providing immersive research and educational experiences to students and artists from diverse backgrounds, and helping to ensure a diverse and well-trained next generation of leaders in polar ecosystem science and stewardship. Ultimately, the results of this project will help us to better understand and prepare for the effects of climate change and develop scientific insights that are relevant far beyond Antarctic ecosystems. The McMurdo Dry Valleys (MDVs) make up an extreme polar desert ecosystem in the largest ice-free region of Antarctica. The organisms in this ecosystem are generally small. Bacteria, microinvertebrates, cyanobacterial mats, and phytoplankton can be found across the streams, soils, glaciers, and ice-covered lakes. These organisms have adapted to the cold and arid conditions that prevail outside of lakes for all but a brief period in the austral summer when the ecosystem is connected by liquid water. In the summer when air temperatures rise barely above freezing, soils warm and glacial meltwater flows through streams into the open moats of lakes. Most biological activity across the landscape occurs in summer. Through the winter, or polar night (6 months of darkness), glaciers, streams, and soil biota are inactive until sufficient light, heat, and liquid water return, while lake communities remain active all year. Over the past 30 years, the MDVs have been disturbed by cooling, heatwaves, floods, rising lake levels, as well as permafrost and lake ice thaw. Considering the clear ecological responses to this variation in physical drivers, and climate models predicting further warming and more precipitation, the MDV ecosystem sits at a threshold between the current extreme cold and dry conditions and an uncertain future. This project seeks to determine how important the legacy of past events and conditions versus current physical and biological interactions shape the current ecosystem. Four hypotheses will be tested, related to 1) whether the status of specific organisms are indicative ecosystem stability, 2) the relationship between legacies of past events to current ecosystem resilience (resistance to big changes), 3) carryover of materials between times of high ecosystem connectivity and activity help to maintain ecosystem stability, and 4) changes in disturbances affect how this ecosystem persists through the annual polar night (i.e., extended period of dark and cold). Technical Abstract In this iteration of the McMurdo LTER project (MCM6), the project team will test ecological connectivity and stability theory in a system subject to strong physical drivers (geological legacies, extreme seasonality, and contemporary climate change) and driven by microbial organisms. Since microorganisms regulate most of the world\u2019s critical biogeochemical functions, these insights will be relevant far beyond polar ecosystems and will inform understanding and expectations of how natural and managed ecosystems respond to ongoing anthropogenic global change. MCM6 builds on previous foundational research, both in Antarctica and within the LTER network, to consider the temporal aspects of connectivity and how it relates to ecosystem stability. The project will examine how changes in the temporal variability of ecological connectivity interact with the legacies of the existing landscape that have defined habitats and biogeochemical cycling for millennia. The project team hypothesizes that the structure and functioning of the MDV ecosystem is dependent upon legacies and the contemporary frequency, duration, and magnitude of ecological connectivity. This hypothesis will be tested with new and continuing monitoring, experiments, and analyses of long-term datasets to examine: 1) the stability of these ecosystems as reflected by sentinel taxa, 2) the relationship between ecological legacies and ecosystem resilience, 3) the importance of material carryover during periods of low connectivity to maintaining biological activity and community stability, and 4) how changes in disturbance dynamics disrupt ecological cycles through the polar night. Tests of these hypotheses will occur in field and modeling activities using new and long-term datasets already collected. New datasets resulting from field activities will be made freely available via widely-known online databases (MCM LTER and EDI). The project team has also developed six Antarctic Core Ideas that encompass themes from data literacy to polar food webs and form a consistent thread across the education and outreach activities. Building on past success, collaborations will be established with teachers and artists embedded within the science teams, who will work to develop educational modules with science content informed by direct experience and artistic expression. Undergraduate mentoring efforts will incorporate computational methods through a new data-intensive scientific training program for MCM REU students. The project will also establish an Antarctic Research Experience for Community College Students at CU Boulder, to provide an immersive educational and research experience for students from diverse backgrounds in community colleges. MCM LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science and stewardship. Historically underrepresented participation will be expanded at each level of the project. To aid in these efforts, the project has established Education \u0026 Outreach and Diversity, Equity, and Inclusion committees to lead, coordinate, support, and integrate these activities through all aspects of MCM6. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 162.87, "geometry": "POINT(162.87 -77)", "instruments": null, "is_usap_dc": true, "keywords": "COMMUNITY DYNAMICS; ABLATION ZONES/ACCUMULATION ZONES; SOIL TEMPERATURE; DIATOMS; FIELD INVESTIGATION; PERMANENT LAND SITES; BUOYS; GROUND-BASED OBSERVATIONS; SEDIMENTS; SNOW WATER EQUIVALENT; SPECIES/POPULATION INTERACTIONS; WATER-BASED PLATFORMS; FIXED OBSERVATION STATIONS; VIRUSES; PHYTOPLANKTON; ACTIVE LAYER; FIELD SURVEYS; RADIO TRANSMITTERS; DATA COLLECTIONS; ECOLOGICAL DYNAMICS; LANDSCAPE; GROUND WATER; SNOW/ICE CHEMISTRY; LAND-BASED PLATFORMS; ANIMALS/INVERTEBRATES; ECOSYSTEM FUNCTIONS; HUMIDITY; GEOCHEMISTRY; SURFACE WINDS; RIVERS/STREAM; GLACIER MASS BALANCE/ICE SHEET MASS BALANCE; SNOW; LAND RECORDS; ATMOSPHERIC PRESSURE; SURFACE TEMPERATURE; ATMOSPHERIC RADIATION; BACTERIA/ARCHAEA; AIR TEMPERATURE; GLACIERS; SNOW/ICE TEMPERATURE; SOIL CHEMISTRY; METEOROLOGICAL STATIONS; WATER QUALITY/WATER CHEMISTRY; TERRESTRIAL ECOSYSTEMS; MOORED; PROTISTS; STREAMFLOW STATION; Dry Valleys; LAKE/POND; LAKE ICE; SNOW DEPTH; AQUATIC ECOSYSTEMS; SNOW DENSITY; FIELD SITES", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Gooseff, Michael N.; Adams, Byron; Barrett, John; Diaz, Melisa A.; Doran, Peter; Dugan, Hilary A.; Mackey, Tyler; Morgan-Kiss, Rachael; Salvatore, Mark; Takacs-Vesbach, Cristina; Zeglin, Lydia H.", "platforms": "LAND-BASED PLATFORMS; LAND-BASED PLATFORMS \u003e FIELD SITES; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e DATA COLLECTIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e RADIO TRANSMITTERS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e METEOROLOGICAL STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e STREAMFLOW STATION; WATER-BASED PLATFORMS; WATER-BASED PLATFORMS \u003e BUOYS; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e BUOYS", "repo": "Environmental Data Initiative (EDI)", "repositories": "Environmental Data Initiative (EDI)", "science_programs": "LTER", "south": -77.0, "title": "LTER: MCM6 - The Roles of Legacy and Ecological Connectivity in a Polar Desert Ecosystem", "uid": "p0010440", "west": 162.87}, {"awards": "2203177 Steinberg, Deborah; 2203176 Cimino, Megan", "bounds_geometry": "POLYGON((-80 -60,-77 -60,-74 -60,-71 -60,-68 -60,-65 -60,-62 -60,-59 -60,-56 -60,-53 -60,-50 -60,-50 -61,-50 -62,-50 -63,-50 -64,-50 -65,-50 -66,-50 -67,-50 -68,-50 -69,-50 -70,-53 -70,-56 -70,-59 -70,-62 -70,-65 -70,-68 -70,-71 -70,-74 -70,-77 -70,-80 -70,-80 -69,-80 -68,-80 -67,-80 -66,-80 -65,-80 -64,-80 -63,-80 -62,-80 -61,-80 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 10 Aug 2023 00:00:00 GMT", "description": "This project is co-funded by a collaboration between the Directorate for Geosciences and Office of Advanced Cyberinfrastructure to support Artificial Intelligence/Machine Learning and open science activities in the geosciences. Machine learning model will be used in this project to predict the distributions of five zooplankton species in the western Antarctic Peninsula (wAP) based on oceanographic properties. The project will take advantage of a long-term series collected by the Palmer Long-Term Ecological Research (LTER) program that collects annual data on physics, chemistry, phytoplankton (or food), zooplankton and predators (seabirds, whales and seals). By analyzing this dataset and combining it with other data collected by national and international programs, this project will provide understanding and prediction of zooplankton distribution and abundance in the wAP. The machine learning models will be based on environmental properties extracted from remote sensing images thus providing ecosystem knowledge as it decreases human footprint in Antarctica. The relationship between species distribution and habitat are key for distinguishing natural variability from climate impacts on zooplankton and their predators. This research benefits NSF mission by expanding fundamental knowledge of Antarctic systems, biota, and processes as well as aligning with data and sample reuse strategies in Polar Research. The project will benefit society by supporting two female early-career scientists, a post-doctoral fellow and a graduate student. Polar literacy will be promoted through an existing partnership with Out Of School activities that target Science, Technology, Engineering and Mathematics (STEM) education, expected to reach 120,000 students from under-represented minorities in STEM annually. The project will also contribute to evaluate the ecosystem in the proposed Marine Protected Area in the wAP, subject to krill fishery. Results will be made available publicly through an interactive web application. The Principal Investigators propose to address three main questions: 1) Can geomorphic features, winter preconditioning and summer ocean conditions be used to predict the austral summer distribution of zooplankton species along the wAP? 2) What are the spatial and temporal patterns in modeled zooplankton species distribution along the wAP? And 3) What are the patterns of overlap in zooplankton and predator species? The model will generate functional relationships between zooplankton distribution and environmental variables and provide Zooplankton Distribution Models (ZDMs) along the Antarctic Peninsula. The Palmer LTER database will be combined with the NOAA AMLR data for the northern wAP, and KRILLBASE, made public by the British Antarctic Survey\u2019s Polar Data Center. This project will generate 1) annual environmental spatial layers on the Palmer LTER resolution grid within the study region, 2) annual species-specific standardized zooplankton net data from different surveys, 3) annual species-specific predator sightings on a standardized grid, and 4) ecological model output. Ecological model output will include annual predictions of zooplankton species distributions, consisting of 3-dimensional fields (x,y,t) for the 5 main zooplankton groups, including Antarctic krill, salps and pteropods. Predictions will be derived from merging in situ survey data with environmental data, collected in situ or by remote sensing. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -50.0, "geometry": "POINT(-65 -65)", "instruments": null, "is_usap_dc": true, "keywords": "ANIMAL ECOLOGY AND BEHAVIOR; PELAGIC; BIRDS; SPECIES/POPULATION INTERACTIONS; ANIMALS/INVERTEBRATES; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cimino, Megan; Steinberg, Deborah", "platforms": null, "repositories": null, "science_programs": null, "south": -70.0, "title": "Collaborative Research: Harvesting Long-term Survey Data to Develop Zooplankton Distribution Models for the Antarctic Peninsula", "uid": "p0010429", "west": -80.0}, {"awards": "2224611 Schofield, Oscar; 2026045 Schofield, Oscar", "bounds_geometry": "POLYGON((-79.65 -63.738,-77.9728 -63.738,-76.29560000000001 -63.738,-74.61840000000001 -63.738,-72.94120000000001 -63.738,-71.26400000000001 -63.738,-69.58680000000001 -63.738,-67.9096 -63.738,-66.2324 -63.738,-64.5552 -63.738,-62.878 -63.738,-62.878 -64.3683,-62.878 -64.9986,-62.878 -65.6289,-62.878 -66.25919999999999,-62.878 -66.8895,-62.878 -67.5198,-62.878 -68.1501,-62.878 -68.7804,-62.878 -69.41069999999999,-62.878 -70.041,-64.5552 -70.041,-66.2324 -70.041,-67.9096 -70.041,-69.5868 -70.041,-71.26400000000001 -70.041,-72.94120000000001 -70.041,-74.61840000000001 -70.041,-76.29560000000001 -70.041,-77.9728 -70.041,-79.65 -70.041,-79.65 -69.41069999999999,-79.65 -68.7804,-79.65 -68.1501,-79.65 -67.5198,-79.65 -66.8895,-79.65 -66.25919999999999,-79.65 -65.6289,-79.65 -64.9986,-79.65 -64.3683,-79.65 -63.738))", "dataset_titles": "Expedition Data of LMG2301; Expedition Data of NBP2113; Palmer LTER data in the Environmental Data Initiative Repository", "datasets": [{"dataset_uid": "200370", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP2113", "url": "https://www.rvdata.us/search/cruise/NBP2113"}, {"dataset_uid": "200367", "doi": "", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "Palmer LTER data in the Environmental Data Initiative Repository", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=PAL"}, {"dataset_uid": "200371", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG2301", "url": "https://www.rvdata.us/search/cruise/LMG2301"}], "date_created": "Wed, 26 Jul 2023 00:00:00 GMT", "description": "Part 1: Non-technical description The goal of all LTER sites is to conduct policy-relevant ecosystem research for questions that require tens of years of data and cover large geographical areas. The Palmer Antarctica Long Term Ecological Research (PAL-LTER) site has been in operation since 1990 and has been studying how the marine ecosystem west of the Antarctica Peninsula (WAP) is responding to a climate that is changing as rapidly as any place on the Earth. The study is evaluating how warming conditions and decreased ice cover leading to extended periods of open water are affecting many aspects of ecosystem function. The team is using combined cutting-edge approaches including yearly ship-based research cruises, small-boat weekly sampling, autonomous vehicles, animal biologging, oceanographic floats and seafloor moorings, manipulative lab-based process studies and modeling to evaluate both seasonal and annual ecosystem responses. These combined approaches are allowing for the study the ecosystem changes at scales needed to assess both short-term and long-term drivers. The study region also includes submarine canyons that are special regions of enhanced biological activity within the WAP. This research program is paired with a comprehensive education and outreach program promoting the global significance of Antarctic science and research. In addition to training for graduate and undergraduate students, they are using newly-developed Polar Literacy Principles as a foundation in a virtual schoolyard program that shares polar instructional materials and provides learning opportunities for K-12 educators. The PAL-LTER team is also leveraging the development of Out of School Time materials for afterschool and summer camp programs, sharing Palmer LTER-specific teaching materials with University, Museum, and 4-H Special Interest Club partners. Part 2: Technical description Polar ecosystems are among the most rapidly changing on Earth. The Palmer LTER (PAL-LTER) program builds on three decades of coordinated research along the western side of the Antarctic Peninsula (WAP) to gain new mechanistic and predictive understanding of ecosystem changes in response to disturbances spanning long-term decadal (\u2018press\u2019) drivers and changes due to higher-frequency (\u2018pulse\u2019) drivers, such as large storms and extreme seasonal anomaly in sea ice cover. The influence of major natural climate modes that modulate variations in sea ice, weather, and oceanographic conditions to drive changes in ecosystem structure and function (e.g., El Ni\u00f1o Southern Oscillation and Southern Annular Mode) are being studied at multiple time scales \u2013from diel, seasonal, interannual, to decadal intervals, and space scales\u2013from hemispheric to global scale investigated by remote sensing, the regional scales. Specifically, the team is evaluating how variability of physical properties (such as vertical and alongshore connectivity processes) interact to modulate biogeochemical cycling and community ecology in the WAP region. The study is providing an evaluation of ecosystem resilience and ecological responses to long-term \u201cpress-pulse\u201d drivers and a decadal-level reversal in sea ice coverage. This program is providing fundamental understanding of population and biogeochemical responses for a marine ecosystem experiencing profound change. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -62.878, "geometry": "POINT(-71.26400000000001 -66.8895)", "instruments": null, "is_usap_dc": true, "keywords": "SEA ICE; PLANKTON; PELAGIC; West Antarctic Shelf; R/V NBP; OCEAN MIXED LAYER; COMMUNITY DYNAMICS; PENGUINS; R/V LMG", "locations": "West Antarctic Shelf", "north": -63.738, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Schofield, Oscar; Steinberg, Deborah", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "EDI; R2R", "science_programs": "LTER", "south": -70.041, "title": "LTER: Ecological Response and Resilience to \u201cPress-Pulse\u201d Disturbances and a Recent Decadal Reversal in Sea Ice Trends Along the West Antarctic Peninsula", "uid": "p0010426", "west": -79.65}, {"awards": "2142491 Young, Jodi", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 26 Jul 2023 00:00:00 GMT", "description": "Sea ice in Antarctic coastal waters shape ecosystems, both in the surface waters and at the bottom of the ocean, environments that depend on algae living in sea ice for their productivity. With high variability in sea ice formation and melt between years and as a response to climate change, it is of importance to obtain better understanding of the interaction of sea ice with algae, as well as provide better data for global climate models. This project will accomplish those goals by measuring phytoplankton growth and cellular properties in sea ice with experiments performed using an ice tank. Laboratory experiments will be based on previous observations in the Antarctic Peninsula coastal waters, providing realistic conditions to emulate. The scientific importance of the proposed work aligns with the National Science Foundation goals to understand the biological and chemical properties of sea ice bio-geo-chemistry and its feedbacks with seasonal sea ice dynamics and climate. The finding from this project will be of interest to a broad scientific community, including oceanographers, biologists, chemists, and ecosystem and ocean modelers. To address the scarcity of data on sea ice microbes that limits our ability to predict future Antarctic climate with accuracy, the principal investigator will develop an Antarctic Science Minor in order to train future scientists with an environmental perspective and prepare the future US workforce with a strong scientific background on Earth and Biological Sciences. There is a paucity of data to understand the processes underlying observed patters in sea ice quality and their interaction with the sea-ice microbial community. This project will provide a mechanistic understanding of primary production and physiology of sympagic algae over the seasonal cycle of formation and melt of Antarctic sea ice. Although sea ice is central to the Antarctic coastal ecosystems, little is known of how they affect, and are in turn affected, by sea-ice algae. This project concentrates on first-year sea ice, forming and melting each year, creating unique and very dynamic habitats. The study will be structured by 4 main objectives: 1) how different algal species adapt to the seasonal changes in sea ice conditions, 2) how different methods to measure primary production (carbon dioxide drawdown, oxygen production and variable fluorescence) relate in sea ice and differ from sea water measurements, 3) how sympagic algae influence the physical structure of sea ice, 4) how sympagic algae contribute to organic matter cycling during ice melt. Due to expected changes in sea ice due to climate change, this study is uniquely positioned to provide needed data on short-term and seasonal processes. Results from this study will be useful to refine models of algal production in Antarctic and Arctic ecosystems, data not available to date as sea ice and its biogeochemistry are often poorly represented in earth system models. This project will also provide education for graduate and undergraduate students as well as material to develop class curriculum for middle-school students. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MARINE ECOSYSTEMS", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Young, Jodi", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "CAREER: Experimentally Testing the Role of Sympagic Algae in Sea-ice Environments using a Laboratory Scale Ice-tank.", "uid": "p0010425", "west": -180.0}, {"awards": "2302832 Reilly, Brendan", "bounds_geometry": "POLYGON((-70 -55,-67 -55,-64 -55,-61 -55,-58 -55,-55 -55,-52 -55,-49 -55,-46 -55,-43 -55,-40 -55,-40 -56.1,-40 -57.2,-40 -58.3,-40 -59.4,-40 -60.5,-40 -61.6,-40 -62.7,-40 -63.8,-40 -64.9,-40 -66,-43 -66,-46 -66,-49 -66,-52 -66,-55 -66,-58 -66,-61 -66,-64 -66,-67 -66,-70 -66,-70 -64.9,-70 -63.8,-70 -62.7,-70 -61.6,-70 -60.5,-70 -59.4,-70 -58.3,-70 -57.2,-70 -56.1,-70 -55))", "dataset_titles": "NRM, ARM, IRM, and magnetic susceptibility investigations on U1537 and U1538 cube samples; Rock magnetic data from IODP Exp. 382 Sites U1537 and U1538 to support Reilly et al. \"A geochemical mechanism for \u003e10 m offsets of magnetic reversals inferred from the comparison of two Scotia Sea drill sites\"", "datasets": [{"dataset_uid": "200412", "doi": "10.7288/V4/MAGIC/19778", "keywords": null, "people": null, "repository": "MagIC (EarthRef)", "science_program": null, "title": "NRM, ARM, IRM, and magnetic susceptibility investigations on U1537 and U1538 cube samples", "url": "http://dx.doi.org/10.7288/V4/MAGIC/19778"}, {"dataset_uid": "200411", "doi": "10.5281/zenodo.10035106", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Rock magnetic data from IODP Exp. 382 Sites U1537 and U1538 to support Reilly et al. \"A geochemical mechanism for \u003e10 m offsets of magnetic reversals inferred from the comparison of two Scotia Sea drill sites\"", "url": "https://zenodo.org/records/10035107"}], "date_created": "Wed, 12 Jul 2023 00:00:00 GMT", "description": "The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica\u2019s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica\u2019s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth\u0027s most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change. The proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica\u2019s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -40.0, "geometry": "POINT(-55 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "PALEOMAGNETISM; SEDIMENTS; Scotia Sea", "locations": "Scotia Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE \u003e PLIOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e NEOGENE; PHANEROZOIC \u003e CENOZOIC", "persons": "Reilly, Brendan", "platforms": null, "repo": "MagIC (EarthRef)", "repositories": "MagIC (EarthRef); Zenodo", "science_programs": null, "south": -66.0, "title": "Collaborative Research: Linking Marine and Terrestrial Sedimentary Evidence for Plio-pleistocene Variability of Weddell Embayment and Antarctic Peninsula Glaciation", "uid": "p0010424", "west": -70.0}, {"awards": "2001646 Chereskin, Teresa; 1542902 Chereskin, Teresa", "bounds_geometry": "POLYGON((-68 -54,-66.7 -54,-65.4 -54,-64.1 -54,-62.8 -54,-61.5 -54,-60.2 -54,-58.9 -54,-57.6 -54,-56.3 -54,-55 -54,-55 -55,-55 -56,-55 -57,-55 -58,-55 -59,-55 -60,-55 -61,-55 -62,-55 -63,-55 -64,-56.3 -64,-57.6 -64,-58.9 -64,-60.2 -64,-61.5 -64,-62.8 -64,-64.1 -64,-65.4 -64,-66.7 -64,-68 -64,-68 -63,-68 -62,-68 -61,-68 -60,-68 -59,-68 -58,-68 -57,-68 -56,-68 -55,-68 -54))", "dataset_titles": "Joint Archive for shipboard ADCP data; World Ocean Database", "datasets": [{"dataset_uid": "200354", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Joint Archive for shipboard ADCP data", "url": "https://uhslc.soest.hawaii.edu/sadcp/"}, {"dataset_uid": "200355", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "World Ocean Database", "url": "https://www.nodc.noaa.gov/OC5/SELECT/dbsearch/dbsearch.html"}], "date_created": "Fri, 03 Mar 2023 00:00:00 GMT", "description": "Part 1: On frequent crossings of the Drake Passage on the US Antarctic vessel ARSV Laurence M. Gould, a range of underway measurements are taken. These data represent one of the few repeat year around shipboard measurements in the Southern Ocean. With close to two decades of data now available, the primary science objectives of this proposal are to continue to analyze the Drake Passage time series. Part 2: Some of the analyses are (1) describe and relate the seasonal and long-term ocean energy distribution to wind, buoyancy and topographic forcing and sinks, and (2) describe and relate seasonal and long-term changes in the ACC fronts, water masses and upwelling to biogeochemical and climate variability. High-resolution, near-repeat Expendable Bathythermograph (XBT) and Acoustic Doppler Current Profiler (ADCP) transect sampling in Drake Passage is thus used to study modes of variability in ocean temperature, salinity, currents and backscatter in the Antarctic Circumpolar Current (ACC) on seasonal to interannual time frames, and on space scales from current cores to eddies. This project is a continuation of the longstanding support for collecting the ADCP and other underway data on USAP vessels, such as the ASRV Laurence M Gould This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -55.0, "geometry": "POINT(-61.5 -59)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "R/V LMG; Drake Passage; WATER TEMPERATURE; Antarctic Circumpolar Current; Heat Flux", "locations": "Drake Passage", "north": -54.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Chereskin, Teresa; Sprintall, Janet", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -64.0, "title": "High Resolution Underway Air-Sea Observations in Drake Passage for Climate Science", "uid": "p0010409", "west": -68.0}, {"awards": "1543511 Stephens, Britton; 1543457 Munro, David", "bounds_geometry": "POLYGON((-73 -53,-71.2 -53,-69.4 -53,-67.6 -53,-65.8 -53,-64 -53,-62.2 -53,-60.4 -53,-58.6 -53,-56.8 -53,-55 -53,-55 -54.4,-55 -55.8,-55 -57.2,-55 -58.6,-55 -60,-55 -61.4,-55 -62.8,-55 -64.2,-55 -65.6,-55 -67,-56.8 -67,-58.6 -67,-60.4 -67,-62.2 -67,-64 -67,-65.8 -67,-67.6 -67,-69.4 -67,-71.2 -67,-73 -67,-73 -65.6,-73 -64.2,-73 -62.8,-73 -61.4,-73 -60,-73 -58.6,-73 -57.2,-73 -55.8,-73 -54.4,-73 -53))", "dataset_titles": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the Southern Ocean, Drake Passage and South Atlantic Ocean in 2018, processed by NOAA (NCEI Accession 0184338); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, Drake Passage, South Atlantic Ocean in 2022 (NCEI Accession 0276577); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Atlantic Ocean in 2021 (NCEI Accession 0246983); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean from 2019-02-16 to 2020-02-11 (NCEI Accession 0208838); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean in 2020 (NCEI Accession 0225445); Underway measurements of pCO2 in the Surface Waters and the Atmosphere During the ARSV Laurence M. Gould 2017 Expeditions processed by NOAA (NCEI Accession 0170337)", "datasets": [{"dataset_uid": "200348", "doi": "https://doi.org/10.7289/v5tq5zt1", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Underway measurements of pCO2 in the Surface Waters and the Atmosphere During the ARSV Laurence M. Gould 2017 Expeditions processed by NOAA (NCEI Accession 0170337)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200349", "doi": "https://doi.org/10.25921/b4jn-ef56", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the Southern Ocean, Drake Passage and South Atlantic Ocean in 2018, processed by NOAA (NCEI Accession 0184338)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200350", "doi": "https://doi.org/10.25921/3ysc-pm11", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean from 2019-02-16 to 2020-02-11 (NCEI Accession 0208838)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200352", "doi": "https://doi.org/10.25921/f94g-zp40", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Atlantic Ocean in 2021 (NCEI Accession 0246983)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200353", "doi": "https://doi.org/10.25921/fq0a-7y11", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, Drake Passage, South Atlantic Ocean in 2022 (NCEI Accession 0276577)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200351", "doi": "https://doi.org/10.25921/z0pk-pv81", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean in 2020 (NCEI Accession 0225445)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}], "date_created": "Wed, 22 Feb 2023 00:00:00 GMT", "description": "The Southern Ocean plays a key role in modulating the global carbon cycle, but the size and even the sign of the global ocean flux terms of the atmospheric burden of man-made CO2 are still uncertain. This is in part due to the lack of measurements in this remote region of the world ocean. This project continues a multi-year time series of shipboard chemical measurements in the Drake Passage to detect changes in the ocean carbon cycle and to improve the understanding of mechanisms driving natural variability and long-term change in the Southern Ocean. This project is a continuation of collection of upper ocean measurements of the underway surface partial pressure of carbon dioxide (pCO2), using frequent ferry crossings of the Drake Passage by the RV/AS LMGould, the USAP supply ship. Overall, more than 200 transects over the past decade (since 2002) have now been accumulated of pCO2 profiles, along with discrete samples for other parameters of interest in studying the ocean carbonate system such as total CO2 (TCO2) values, isotopic (13C/12C and 14C/12C) ratios in surface TCO2. The Drake Passage data are made readily available to the international science community and serve as both validation and constraints of remotely sensed observations and numerical coupled earth systems models.", "east": -55.0, "geometry": "POINT(-64 -60)", "instruments": null, "is_usap_dc": true, "keywords": "Drake Passage; NUTRIENTS; BIOGEOCHEMICAL CYCLES; DISSOLVED GASES; TRACE GASES/TRACE SPECIES", "locations": "Drake Passage", "north": -53.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Munro, David; Sweeney, Colm; Lovenduski, Nicole S; Stephens, Britton", "platforms": null, "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Investigating Biogeochemical Fluxes and Linkages To Climate Change With Multi-Scale Observations In The Drake Passage", "uid": "p0010407", "west": -73.0}, {"awards": "2233016 Blanchard-Wrigglesworth, Edward", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 17 Feb 2023 00:00:00 GMT", "description": "In the austral winter of 2021/2022 a drastic decline in Antarctic sea ice extent has taken place, and February 2022 marked the lowest sea ice extent on record since satellite sea ice observations began in 1979. Combined with the loss of sea ice, the most extreme heat wave ever observed took place over East Antarctica in March 2022 as temperatures climbed over +40\u00b0C from climatology. Extreme events have an oversized footprint in socioeconomic impacts, but also serve as litmus tests for climate predictions. This project will use novel tools to diagnose the factors that led to the record low Antarctic sea ice extent and heat wave focusing on the impact of winds and ocean temperatures. Currently (June 2022) Antarctic sea ice extent remains at record low levels for the time of year, raising the prospect of a long-lasting period of low sea ice extent, yet annual forecasts of Antarctic sea ice do not yet exist. To address this issue, this project will also create exploratory annual sea ice forecasts for the 2022-2024 period. The extreme changes observed in Antarctic sea ice extent and air temperature have questioned our current understanding of Antarctic climate variability. Motivated by the timing of these events and our recent development of novel analysis tools, this project will address the following research questions: (R1) Can local winds account for the observed 2021/2022 sea ice loss, or are remote sea surface temperature (SST) anomalies a necessary ingredient? (R2) Are sea ice conditions over 2022-2024 likely to remain anomalously low? (R3) Can a state-of-the-art climate model simulate a heat wave of comparable magnitude to that observed if it follows the observed circulation that led to the heat wave? The main approach will be to use a nudging technique with a climate model, in which one or several variables in a climate model are nudged toward observed values. The project authors used this tool to attribute Antarctic sea ice variability and trends over 1979-2018 to winds and SST anomalies. This project will apply this tool to the period 2019-2022 to address R1 and R3 by running two different model experiments over this time period in which the winds over Antarctica and SSTs in the Southern Ocean are nudged toward observed values. In addition, we will diagnose the relevant modes of atmospheric variability over 2019-2022 that are known to influence Antarctic sea ice to gain further insight into the 2022 loss of sea ice extent. To address R2, we plan to extend the model simulations but without nudging, using the model as a forecast model (as its 2022 initial conditions will be taken from the end of the nudged simulations and capture important aspects of the observed state). We expect that if current upper ocean heat content is anomalously high, low sea ice extent conditions may continue over 2022-2024, as happened over 2017-2019 following the previous record low of sea ice extent in 2016/2017. To further address R3, we will compare observations and model simulations using novel atmospheric heat transport calculations developed by the project team. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; SURFACE TEMPERATURE", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Blanchard-Wrigglesworth, Edward", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "RAPID: What Caused the Record Warmth and Loss of Antarctic Sea ice in the Austral Summer of 2022, and will Sea Ice Remain Low Over 2022-2024?", "uid": "p0010405", "west": -180.0}, {"awards": "1542723 Alexander, Becky", "bounds_geometry": "POINT(-112.05 -79.28)", "dataset_titles": "WAIS Divide ice core nitrate isotopes", "datasets": [{"dataset_uid": "601456", "doi": "10.15784/601456", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Chemistry; Ice Core Records; Nitrate; Nitrate Isotopes; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Alexander, Becky", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide ice core nitrate isotopes", "url": "https://www.usap-dc.org/view/dataset/601456"}], "date_created": "Mon, 13 Feb 2023 00:00:00 GMT", "description": "The Earth\u0027s atmosphere is a highly oxidizing medium. The abundance of oxidants such as ozone in the atmosphere strongly influences the concentrations of pollutants and greenhouse gases, with implications for human health and welfare. Because oxidants are not preserved in geological archives, knowledge of how oxidants have varied in the past under changing climate conditions is extremely limited. This award will measure a proxy for oxidant concentrations in a West Antarctic ice core over several major climate transitions over the past 50,000 years. These measurements will complement similar measurements from a Greenland ice core, which showed significant changes in atmospheric oxidants over major climate transitions covering this same time period. The addition of measurements from Antarctica will allow researchers to examine if the oxidant changes suggested by the Greenland ice core record are regional or global in scale. Knowledge of how oxidants vary naturally with climate will better inform predictions of the composition of the future atmosphere under a warming climate. This award will support measurements of the isotopic composition of nitrate in a West Antarctic ice core as a proxy for oxidant concentrations in the past atmosphere. The nitrogen isotopes of nitrate provide information on the degree of preservation of nitrate in the ice core record, and thus aid in the interpretation of the observed variability in the observed nitrate concentrations and oxygen isotopes in ice core records. By providing information about the spatial scale of oxidant changes over abrupt climate change events during the last glacial period, this project may also improve our understanding of mechanisms driving these abrupt events. Insight from this project will prove valuable for forecasting the response of stratospheric circulation to climate change, which has large implications for climate feedbacks and tropospheric composition. In addition, the information gleaned from this project on the mechanisms and feedbacks during abrupt climate change events will help determine the likelihood of such rapid events occurring in the future, which would have dramatic impacts on humankind. This award will provide training for one graduate and one undergraduate student, and will support the development of a hands-on activity related to rapid climate change to be used at the annual Polar Science Weekend at the Pacific Science Center in Seattle, WA.", "east": -112.05, "geometry": "POINT(-112.05 -79.28)", "instruments": null, "is_usap_dc": true, "keywords": "Nitrate Isotopes; ICE CORE RECORDS; WAIS Divide; LABORATORY", "locations": "WAIS Divide", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Alexander, Becky", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.28, "title": "Measuring an Ice-core Proxy for Relative Oxidant Abundances over Glacial-interglacial and Rapid Climate changes in a West Antarctic Ice Core", "uid": "p0010403", "west": -112.05}, {"awards": "2146068 Kienle, Sarah", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 12 Sep 2022 00:00:00 GMT", "description": "The leopard seal (Hydrurga leptonyx) is an enigmatic apex predator in the rapidly changing Southern Ocean. As top predators, leopard seals play a disproportionately large role in ecosystem functioning and act as sentinel species that can track habitat changes. How leopard seals respond to a warming environment depends on their adaptive capacity, that is a species\u2019 ability to cope with environmental change. However, leopard seals are one of the least studied apex predators on Earth, hindering our ability to predict how the species is responding to polar environmental changes. Investigating the adaptability of Antarctic biota in a changing system aligns with NSF\u2019s Strategic Vision for Investments in Antarctic and Southern Ocean Research. This research, which is tightly integrated with educational and outreach activities, will increase diversity in STEM and Antarctic science by recruiting students from historically underrepresented groups in STEM and providing training, mentoring, and educational opportunities at an emerging Hispanic Serving Institution and a Historically Black Colleges and Universities campus. This project will improve STEM education and science literacy via museum collaborations, creation of informational videos and original artwork depicting the research. The proposal supports data and sample reuse in polar research and long-term reuse of scientific data, thereby maximizing NSF\u2019s investment in previous field research and reducing operational costs. The researchers will investigate leopard seals adaptive capacity to the warming Southern Ocean by quantifying their ability to move (dispersal ability), adapt (genetic diversity), and change (plasticity). Aim 1 of the research will determine leopard seals\u2019 dispersal ability by assessing their distribution and movement patterns. Aim 2 will quantify genetic diversity by analyzing genetic variability and population structure and Aim 3 will examine phenotypic plasticity by evaluating changes in their ecological niche and physiological responses. The international, multidisciplinary team will analyze existing data (e.g., photographs, census data, life history data, tissue samples, body morphometrics) collected from leopard seals across the Southern Ocean over the last decade. Additionally, land- and ship-based field efforts will generate comparable data from unsampled regions in the Southern Ocean. The research project will analyze these historical and contemporary datasets to evaluate the adaptive capacity of leopard seals against the rapidly warming Southern Ocean. This research is significant because changes in the distribution, genetic diversity, and ecophysiology of leopard seals can dramatically restructure polar and subpolar communities. Further, the research will expand understanding of leopard seals\u2019 ecological role, likely characterizing the species as flexible polar and subpolar predators throughout the Southern Hemisphere. The findings of this research will be relevant for use in ecosystem-based management decisions\u2014including the design of Marine Protected Areas\u2014 across three continents. This study will highlight intrinsic traits that determine species\u2019 adaptive capacity, as well as showcase the dynamic links between polar and subpolar ecosystems. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; SPECIES/POPULATION INTERACTIONS; MARINE ECOSYSTEMS; MAMMALS; Southern Ocean", "locations": "Southern Ocean", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kienle, Sarah; Trumble, Stephen J; Bonin, Carolina", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "Move, Adapt, or Change: Examining the Adaptive Capacity of a Southern Ocean Apex Predator, the Leopard Seal", "uid": "p0010375", "west": null}, {"awards": "2147045 Learman, Deric", "bounds_geometry": "POLYGON((-180 -60,-168 -60,-156 -60,-144 -60,-132 -60,-120 -60,-108 -60,-96 -60,-84 -60,-72 -60,-60 -60,-60 -62,-60 -64,-60 -66,-60 -68,-60 -70,-60 -72,-60 -74,-60 -76,-60 -78,-60 -80,-72 -80,-84 -80,-96 -80,-108 -80,-120 -80,-132 -80,-144 -80,-156 -80,-168 -80,180 -80,171 -80,162 -80,153 -80,144 -80,135 -80,126 -80,117 -80,108 -80,99 -80,90 -80,90 -78,90 -76,90 -74,90 -72,90 -70,90 -68,90 -66,90 -64,90 -62,90 -60,99 -60,108 -60,117 -60,126 -60,135 -60,144 -60,153 -60,162 -60,171 -60,-180 -60))", "dataset_titles": "Physical and geochemical data from shelf sediments eastern Antarctica", "datasets": [{"dataset_uid": "601876", "doi": null, "keywords": "Antarctica; Cryosphere", "people": "Learman, Deric", "repository": "USAP-DC", "science_program": null, "title": "Physical and geochemical data from shelf sediments eastern Antarctica", "url": "https://www.usap-dc.org/view/dataset/601876"}], "date_created": "Tue, 30 Aug 2022 00:00:00 GMT", "description": "Microbes in Antarctic surface marine sediments have an important role in degrading organic matter and releasing nutrients to the ocean. Organic matter degradation is at the center of the carbon cycle in the ocean, providing valuable information on nutrient recycling, food availability to animals and carbon dioxide release to the atmosphere. The functionality of these microbes has been inferred by their genomics, however these methods only address the possible function, not their actual rates. In this project the PIs plan to combine genomics methods with cellular estimates of enzyme abundance and activity as a way to determine the rates of carbon degradation. This project aims to sample in several regions of Antarctica to provide a large-scale picture of the processes under study and understand the importance of microbial community composition and environmental factors, such as primary productivity, have on microbial activity. The proposed work will combine research tools such as metagenomics, meta-transcriptomics, and metabolomics coupled with chemical data and enzyme assays to establish degradation of organic matter in Antarctic sediments. This project benefits NSFs goals of understanding the adaptation of Antarctic organisms to the cold and isolated environment, critical to predict effects of climate change to polar organisms, as well as contribute to our knowledge of how Antarctic organisms have adapted to this environment. Society will benefit from this project by education of 2 graduate students, undergraduates and K-12 students as well as increase public literacy through short videos production shared in YouTube. The PIs propose to advance understanding of polar microbial community function, by measuring enzyme and gene function of complex organic matter degradation in several ocean regions, providing a circum-Antarctic description of sediment processes. Two hypotheses are proposed. The first hypothesis states that many genes for the degradation of complex organic matter will be shared in sediments throughout a sampling transect and that where variations in gene content occur, it will reflect differences in the quantity and quality of organic matter, not regional variability. The second hypothesis states that a fraction of gene transcripts for organic matter degradation will not result in measurable enzyme activity due to post-translational modification or rapid degradation of the enzymes. The PIs will analyze sediment cores already collected in a 2020 cruise to the western Antarctic Peninsula with the additional request of participating in a cruise in 2023 to East Antarctica. The PIs will analyze sediments for metagenomics, meta-transcriptomics, and metabolomics coupled with geochemical data and enzyme assays to establish microbial degradation of complex organic matter in Antarctic sediments. Organic carbon concentrations and content in sediments will be measured with \u03b413C, \u03b415N, TOC porewater fluorescence in bulk organic carbon. Combined with determination of geographical variability as well as dependence on carbon sources, results from this study could provide the basis for new hypotheses on how climate variability, with increased water temperature, affects geochemistry in the Southern Ocean. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 90.0, "geometry": "POINT(-165 -70)", "instruments": null, "is_usap_dc": true, "keywords": "BENTHIC; ECOSYSTEM FUNCTIONS; Weddell Sea; Antarctic Peninsula; SEDIMENT CHEMISTRY; R/V NBP", "locations": "Antarctic Peninsula; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Learman, Deric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Collaborative Research: ANT LIA: Connecting Metagenome Potential to Microbial Function: Investigating Microbial Degradation of Complex Organic Matter Antarctic Benthic Sediments", "uid": "p0010373", "west": -60.0}, {"awards": "1924730 Lazzara, Matthew", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "AMRC Automatic Weather Station project data", "datasets": [{"dataset_uid": "200316", "doi": "10.48567/1hn2-nw60", "keywords": null, "people": null, "repository": "AMRDC", "science_program": null, "title": "AMRC Automatic Weather Station project data", "url": "https://doi.org/10.48567/1hn2-nw60"}], "date_created": "Tue, 23 Aug 2022 00:00:00 GMT", "description": "The Antarctic Automatic Weather Station network is the most extensive surficial meteorological network in the Antarctic, approaching its 30th year at several of its data stations. Its prime focus is also as a long term observational record, to measure the near surface weather and climatology of the Antarctic atmosphere. Antarctic Automatic Weather Stations measure air-temperature, pressure, wind speed and direction at a nominal surface height of ~ 2-3m. Other parameters such as relative humidity and snow accumulation may also be taken. The surface observations from the Antarctic Automatic Weather Station network are also used operationally, for forecast purposes, and in the planning of field work. Surface observations made from the network have also been used to check the validity of satellite and remote sensing observations. The proposed effort informs our understanding of the Antarctic environment and its weather and climate trends over the past few decades. The research has implications for potential future operations and logistics for the US Antarctic Program during the winter season. As a part of this endeavor, all project participants will engage in a coordinated outreach effort to bring the famous Antarctic \"cold\" to public seminars, K-12, undergraduate, and graduate classrooms, and senior citizen centers. This project proposes to use the surface conditions observed by the Antarctic Automatic Weather Station (AWS) network to determine how large-scale modes of climate variability impact Antarctic weather and climate, how the surface observations from the AWS network are linked to surface layer and boundary layer processes. Consideration will also be given to low temperature physical environments such as may be encountered during Antarctic winter, and the best ways to characterize these, and other ?cold pool? phenomena. Observational data from the AWS are collected via Iridium network, or DCS Argos aboard either NOAA or MetOp polar orbiting satellites and thus made available in near real time to operational and synoptic weather forecasters over the GTS (WMO Global Telecommunication System). Being able to support improvements in numerical weather prediction and climate modeling will have lasting impacts on Antarctic science and logistical support. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "SURFACE TEMPERATURE; ATMOSPHERIC PRESSURE; ATMOSPHERIC TEMPERATURE; Antarctica; SURFACE WINDS; HUMIDITY; AIR TEMPERATURE; ATMOSPHERIC WINDS; ATMOSPHERIC PRESSURE MEASUREMENTS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lazzara, Matthew; Welhouse, Lee J", "platforms": null, "repo": "AMRDC", "repositories": "AMRDC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Automatic Weather Station Program 2019-2022", "uid": "p0010370", "west": -180.0}, {"awards": null, "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 23 Aug 2022 00:00:00 GMT", "description": "The Antarctic Automatic Weather Station network is the most extensive surficial meteorological network in the Antarctic, approaching its 30th year at several of its data stations. Its prime focus is also as a long term observational record, to measure the near surface weather and climatology of the Antarctic atmosphere. Antarctic Automatic Weather Stations measure air-temperature, pressure, wind speed and direction at a nominal surface height of ~ 2-3m. Other parameters such as relative humidity and snow accumulation may also be taken. The surface observations from the Antarctic Automatic Weather Station network are also used operationally, for forecast purposes, and in the planning of field work. Surface observations made from the network have also been used to check the validity of satellite and remote sensing observations. The proposed effort informs our understanding of the Antarctic environment and its weather and climate trends over the past few decades. The research has implications for potential future operations and logistics for the US Antarctic Program during the winter season. As a part of this endeavor, all project participants will engage in a coordinated outreach effort to bring the famous Antarctic \"cold\" to public seminars, K-12, undergraduate, and graduate classrooms, and senior citizen centers.\u003cbr/\u003e\u003cbr/\u003eThis project proposes to use the surface conditions observed by the Antarctic Automatic Weather Station (AWS) network to determine how large-scale modes of climate variability impact Antarctic weather and climate, how the surface observations from the AWS network are linked to surface layer and boundary layer processes. Consideration will also be given to low temperature physical environments such as may be encountered during Antarctic winter, and the best ways to characterize these, and other ?cold pool? phenomena. Observational data from the AWS are collected via Iridium network, or DCS Argos aboard either NOAA or MetOp polar orbiting satellites and thus made available in near real time to operational and synoptic weather forecasters over the GTS (WMO Global Telecommunication System). Being able to support improvements in numerical weather prediction and climate modeling will have lasting impacts on Antarctic science and logistical support.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "HUMIDITY; SURFACE WINDS; SURFACE PRESSURE; INCOMING SOLAR RADIATION; SURFACE AIR TEMPERATURE", "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": null, "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Antarctic Automatic Weather Station Program 2019-2022", "uid": "p0010371", "west": null}, {"awards": "2205008 Walker, Catherine", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "Most of the mass loss from the Antarctic Ice Sheet, a major contributor to sea level rise, occurs at its margins, where ice meets the ocean. Glaciers and ice streams flow towards the coast and can go afloat over the water, forming ice shelves. Ice shelves make up almost half of the entire Antarctic coastline, and hold back the flow of inland ice in Antarctica continent; thus they are integral to the overall stability of the Antarctic Ice Sheet. Ice shelves lose mass by two main processes: iceberg calving and basal melting. Temporal and spatial fluctuations in both are driven by various processes; a major driver of ice shelf melt is the heat provided by the neighboring Southern Ocean. Ocean heat, in turn, is driven by various aspects of the ice shelf environment. One of the most significant contributors to changes in the ocean\u2019s heat content is the presence of sea ice. This research will focus on the effects of coastal polynyas (areas of open water amidst sea ice), how they modulate the local ocean environment, and how that environment drives ice shelf basal melting. To date, the relationship between polynyas and ice shelf melt has not been characterized on an Antarctic-wide scale. Understanding the feedbacks between polynya size and duration, ocean stratification, and ice shelf melt, and the strength of those feedbacks, will improve the ability to characterize influences on the long-term stability of ice shelves, and in turn, the Antarctic Ice Sheet as a whole. A critical aspect of this study is that it will provide a framework for understanding ice shelf-ocean interaction across a diverse range of geographic settings. This, together with improvements of various models, will help interpret the impacts of future climate change on these systems, as their responses are likely quite variable and, overall, different from the large-scale response of the ice sheet. This project will also provide a broader context to better design future observational studies of specific coastal polynya and ice shelf processes. This study focuses on four main hypotheses: 1) Variations of coastal polynya extent are correlated with those of the ice shelf melt rates, and this correlation varies around Antarctica; 2) Polynya extent modulates a feedback between ice shelf melt and accretion regimes through stratification of local waters; 3) Polynya extent together with seafloor bathymetry regulate the volume of warm offshore waters that reach ice margins; and 4) The strength of the feedback between polynya and glacier ice varies with geographic setting and influences the long-term stability of the glacial system. Observational data, including ice-penetrating radar, radar and laser altimetry, and in situ hydrographic data, and derived data sets from the Southern Ocean State Estimate (SOSE) project and BedMachine Antarctica, will be used in conjunction with ocean (MIT global circulation model, MITgcm) and ice sheet (Ice sheet and Sea-level System Model, ISSM) models to reveal underlying dynamics. The joint analysis of the observational data enables an investigation of polynya, ocean, and ice shelf signals and their interplay over time across a range of settings. The results of this data analysis also provide inputs and validation data for the modeling tasks, which will allow for characterization of the feedbacks in our observations. The coupled modeling will enable us to examine the interaction between polynya circulation and ice shelves in different dynamical regimes and to understand ice and ocean feedback over time. Diagnosing and interpreting the pan-Antarctic spatial variability of the polynya-ice shelf interaction are the main objectives of this research and separates this study from other projects targeted at the interactive processes in specific regions. As such, this research focuses on seven preliminary target sites around the Antarctic coast to establish a framework for interpreting coupled ice shelf-ocean variability across a diverse range of geographic settings. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; ICE EXTENT; GLACIERS/ICE SHEETS", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science", "paleo_time": null, "persons": "Walker, Catherine; Zhang, Weifeng; Seroussi, Helene", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Investigating the Role of Coastal Polynya Variability in Modulating Antarctic Marine-Terminating Glacier Drawdown", "uid": "p0010364", "west": -180.0}, {"awards": "1654922 de la Pena, Santiago", "bounds_geometry": "POINT(0 -90)", "dataset_titles": " South Pole Weather and Accumulation Measurements 2017-2020", "datasets": [{"dataset_uid": "601591", "doi": "10.15784/601591", "keywords": "Accumulation; Antarctica; Snow; South Pole; Surface Mass Balance", "people": "de la Pe\u00f1a, Santiago", "repository": "USAP-DC", "science_program": null, "title": " South Pole Weather and Accumulation Measurements 2017-2020", "url": "https://www.usap-dc.org/view/dataset/601591"}], "date_created": "Tue, 02 Aug 2022 00:00:00 GMT", "description": "Non-Technical Description: Snow accumulation in the interior of the Antarctic Ice Sheet, and how much snow is redistributed by wind are important components of the climate system of Antarctica, yet remain largely unknown. Because of the extreme meteorological conditions found in Antarctica, direct observations of snowfall and related weather are few, leaving a gap in the regional climate records in the continent. Snow accumulation across the Antarctic Ice Sheet is a critical component for the assessment of the contribution of Antarctica to sea level rise, and accurate measurements are required to evaluate results from regional climate models, used to reconstruct climate trends of the recent past for the whole ice sheet. Owing to the size of Antarctica alone, small fluctuations in the total snow accumulation at the surface have a significant effect on the mass budget of the ice sheet and thus on global sea level. In this work will develop an instrument suite for deployment at the South Pole research station in Antarctica. The monitoring station will have new state-of-the-art sensors will record measurements of weather, snow accumulation, and structural conditions within the layer of packed snow. The autonomous system will be tested in the coldest and darkest winter on the planet, and will provide the first continuous measurements of snow accumulation processes in the interior of the ice sheet, which will be used to validate atmospheric and regional climate models. Technical Description: The overarching goal of the proposed work is to improve our understanding of the spatiotemporal variability in ice-sheet surface mass balance and densification rates within the layer of firn, a layer roughly 100 m thick consisting of the buried and compacted snow that has yet to densify into solid ice. For this, we will A) design and install a cost-efficient, reliable, and easily deployable surface mass balance and firn monitoring system for Antarctica; B) adapt the system to operate autonomously for long periods of time under the harshest meteorological conditions; C) use observations for evaluation of surface mass balance simulated by atmospheric reanalyzes and regional climate model; and D) measure the surface mass balance, surface density, and firn compaction rates to derive ice sheet surface elevation change in areas with low ice dynamics. The set up of the monitoring station is unique in that it is able to monitor separately height change due to surface mass balance variability and absolute surface mass balance, the latter in units of water equivalence, and differentiation of the two is crucial for understanding the role of surface processes in ice sheet mass balance. An installed sonic ranger will provide hourly measurements of surface height change that is due to snow accumulation. Surface height change alone is not sufficient to evaluate atmospheric models of surface mass balance, which is measured in in units of mass; a key variable missing is density. To overcome this, the system will be equipped with a SnowFox sensor that is able to capture the variations in surface mass balance in terms of mass through time. Combining the height change with mass change will allow us to determine the density of the material as well, which is very important for conversion of observed height changes due to surface processes into mass changes. Therefore, we aim to better evaluate the short-term variability in surface height and mass fluctuations due to surface mass balance to improve our understanding of the total mass change and to evaluate atmospheric models, which are typically used for ice sheet-wide mass balance studies.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": null, "is_usap_dc": true, "keywords": "South Pole; SNOW", "locations": "South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Instrumentation and Facilities; Antarctic Instrumentation and Support; Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "de la Pe\u00f1a, Santiago", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "EAGER: An Operational System to Measure Surface Mass Balance Deep in the Interior of the Antarctic Ice Sheet", "uid": "p0010360", "west": 0.0}, {"awards": "1643431 Bitz, Cecilia", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Analysis code, processed observational data and climate model output required to produce figures for Roach et al (2022); Model output: CICE experiments with varying floe and wave physics described in Roach et al. (2019); Model output from experiments (FSD-M21) described in Cooper et al 2022.; Model output from experiments (IC4M1) described in Cooper et al 2022.; Model output from experiments (IC4M2) described in Cooper et al 2022.; Model output from experiments (IC4M3rad) described in Cooper et al 2022.; Model output from experiments (IC4M4) described in Cooper et al 2022.; Model output from experiments (IC4M5) described in Cooper et al 2022.; Model output from experiments (IC4M7) described in Cooper et al 2022.; Model output: NEMO-CICE with an emergent sea ice floe size distribution described in Roach et al (2018)", "datasets": [{"dataset_uid": "200308", "doi": "10.5281/zenodo.5913959", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Analysis code, processed observational data and climate model output required to produce figures for Roach et al (2022)", "url": "https://zenodo.org/record/5913959"}, {"dataset_uid": "200309", "doi": "10.5281/zenodo.3463580", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output: CICE experiments with varying floe and wave physics described in Roach et al. (2019)", "url": "https://zenodo.org/record/3463580"}, {"dataset_uid": "200310", "doi": "10.5281/zenodo.1193930", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output: NEMO-CICE with an emergent sea ice floe size distribution described in Roach et al (2018)", "url": "https://zenodo.org/record/1193930"}, {"dataset_uid": "200301", "doi": "10.5281/zenodo.6213441", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (IC4M1) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6213441"}, {"dataset_uid": "200302", "doi": "10.5281/zenodo.6213793", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (IC4M2) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6213793"}, {"dataset_uid": "200303", "doi": "10.5281/zenodo.6214364", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (IC4M3rad) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6214364"}, {"dataset_uid": "200304", "doi": "10. 5281/zenodo.6214555", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (IC4M4) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6214555"}, {"dataset_uid": "200305", "doi": "10.5281/zenodo.6214998", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (IC4M5) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6214998"}, {"dataset_uid": "200306", "doi": "10.5281/zenodo.6212423", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (IC4M7) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6212423"}, {"dataset_uid": "200307", "doi": "10.5281/zenodo.6212232", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Model output from experiments (FSD-M21) described in Cooper et al 2022.", "url": "https://zenodo.org/record/6212232"}], "date_created": "Tue, 19 Jul 2022 00:00:00 GMT", "description": "Sea-ice coverage surrounding Antarctica has expanded during the era of satellite observations, in contrast to rapidly shrinking Arctic sea ice. Most climate models predict Antarctic sea ice loss, rather than growth, indicating that there is much to learn about Antarctic sea ice in terms of its natural variability, processes and interactions affecting annual growth and retreat, and the impact of atmospheric factors such increasing greenhouse gases and stratospheric ozone depletion. This project is designed to improve model simulations of sea ice and examine the role of wind and wave forcing on changes in sea ice around Antarctica. This project seeks to explain basic interactions of the coupled atmosphere, ocean, and ice dynamics in the Antarctic climate system, especially in the region near the sea ice edge. The summer evolution of sea ice cover and the near surface heat exchange of atmosphere and ocean depend on the geometric distribution of floes and the open water surrounding them. The distribution of floes has the greatest impact on the sea ice state in the marginal seas, where the distribution itself can vary rapidly. This project would develop and implement a model of sea ice floes in the Los Alamos sea ice model, known as CICE5. This sea ice component would be coupled to the third generation WaveWatch model within the Community Climate System Model Version 2. The coupled model would be used to study sea ice-wave interactions and the role of modeling sea ice floes in the Antarctic. The broader impacts of this project include outreach, support of female scientists, and improvement of the sea-ice codes in widely used climate models.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ICE FLOES; Southern Ocean; SEA ICE", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Bitz, Cecilia", "platforms": null, "repo": "Zenodo", "repositories": "Zenodo", "science_programs": null, "south": -90.0, "title": "The Role of Wave-sea Ice Floe Interactions in Recent Antarctic Sea Ice Change", "uid": "p0010350", "west": -180.0}, {"awards": "1744885 Moline, Mark", "bounds_geometry": "POLYGON((-64.643 -64.703149,-64.5388975 -64.703149,-64.43479500000001 -64.703149,-64.3306925 -64.703149,-64.22659 -64.703149,-64.1224875 -64.703149,-64.018385 -64.703149,-63.9142825 -64.703149,-63.81018 -64.703149,-63.706077500000006 -64.703149,-63.601975 -64.703149,-63.601975 -64.7258003,-63.601975 -64.7484516,-63.601975 -64.77110289999999,-63.601975 -64.7937542,-63.601975 -64.8164055,-63.601975 -64.8390568,-63.601975 -64.86170809999999,-63.601975 -64.8843594,-63.601975 -64.9070107,-63.601975 -64.929662,-63.706077500000006 -64.929662,-63.81018 -64.929662,-63.9142825 -64.929662,-64.018385 -64.929662,-64.1224875 -64.929662,-64.22659 -64.929662,-64.3306925 -64.929662,-64.43479500000001 -64.929662,-64.5388975 -64.929662,-64.643 -64.929662,-64.643 -64.9070107,-64.643 -64.8843594,-64.643 -64.86170809999999,-64.643 -64.8390568,-64.643 -64.8164055,-64.643 -64.7937542,-64.643 -64.77110289999999,-64.643 -64.7484516,-64.643 -64.7258003,-64.643 -64.703149))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 18 Jul 2022 00:00:00 GMT", "description": "This research project will use specially designed autonomous underwater vehicles (AUVs) to investigate interactions between Adelie and Gentoo penguins (the predators) and their primary food source, Antarctic krill (prey). While it has long been known that penguins feed on krill, details about how they search for food and target individual prey items is less well understood. Krill aggregate in large swarms, and the size or the depth of these swarms may influence the feeding behavior of penguins. Similarly, penguin feeding behaviors may differ based on characteristics of the environment, krill swarms, and the presence of other prey and predator species. This project will use specialized smart AUVs to simultaneously collect high-resolution observations of penguins, their prey, and environmental conditions. Data will shed light on strategies used by penguins prove foraging success during the critical summer chick-rearing period. This will improve predictions of how penguin populations may respond to changing environmental conditions in the rapidly warming Western Antarctic Peninsula region. Greater understanding of how individual behaviors shape food web structure can also inform conservation and management efforts in other marine ecosystems. This project has a robust public education and outreach plan linked with the Birch and Monterey Bay Aquariums. Previous studies have shown that sub-mesoscale variability (1-10 km) in Antarctic krill densities and structure impact the foraging behavior of air-breathing predators. However, there is little understanding of how krill aggregation characteristics are linked to abundance on fine spatial scales, how these patterns are influenced by the habitat, or how prey characteristics influences the foraging behavior of predators. These data gaps remain because it is extremely challenging to collect detailed data on predators and prey simultaneously at the scale of an individual krill patch and single foraging event. Building on previously successful efforts, this project will integrate echosounders into autonomous underwater vehicles (AUVs), so that oceanographic variables and multi-frequency acoustic scattering from both prey and penguins can be collected simultaneously. This will allow for quantification of the environment at the scale of individual foraging events made by penguins during the critical 50+ day chick-rearing period. Work will be centered near Palmer Station, where long-term studies have provided significant insight into predator and prey population trends. The new data to be collected by this project will test hypotheses about how penguin prey selection and foraging behaviors are influenced by physical and biological features of their ocean habitat at extremely fine scale. By addressing the dynamic relationship between individual penguins, their prey, and habitat at the scale of individual foraging events, this study will begin to reveal the important processes regulating resource availability and identify what makes this region a profitable foraging habitat and breeding location. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -63.601975, "geometry": "POINT(-64.1224875 -64.8164055)", "instruments": null, "is_usap_dc": true, "keywords": "COASTAL; COMMUNITY DYNAMICS; ECOSYSTEM FUNCTIONS; SPECIES/POPULATION INTERACTIONS; Palmer Station; MICROALGAE; PENGUINS; ANIMALS/INVERTEBRATES", "locations": "Palmer Station", "north": -64.703149, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Moline, Mark; Benoit-Bird, Kelly; Cimino, Megan", "platforms": null, "repositories": null, "science_programs": null, "south": -64.929662, "title": "Collaborative Research: Linking Predator Behavior and Resource Distributions: Penguin-directed Exploration of an Ecological Hotspot", "uid": "p0010347", "west": -64.643}, {"awards": "1745009 Kohut, Josh; 1745011 Klinck, John; 1744884 Oliver, Matthew; 1745081 Bernard, Kim; 1745023 Hennon, Tyler; 1745018 Fraser, William", "bounds_geometry": "POLYGON((-75 -60,-73 -60,-71 -60,-69 -60,-67 -60,-65 -60,-63 -60,-61 -60,-59 -60,-57 -60,-55 -60,-55 -61,-55 -62,-55 -63,-55 -64,-55 -65,-55 -66,-55 -67,-55 -68,-55 -69,-55 -70,-57 -70,-59 -70,-61 -70,-63 -70,-65 -70,-67 -70,-69 -70,-71 -70,-73 -70,-75 -70,-75 -69,-75 -68,-75 -67,-75 -66,-75 -65,-75 -64,-75 -63,-75 -62,-75 -61,-75 -60))", "dataset_titles": "Antarctic ACROBAT data; CTD Data from IFCB Sampling; Finite Time Lyapunov Exponent Results, Calculated from High Frequency Radar Observed Surface Currents; High Frequency Radar, Palmer Deep; IFCB Image Data; Relative Particle Density; SWARM AMLR moorings - acoustic data; SWARM Glider Data near Palmer Deep; WAP model float data; Winds from Joubin and Wauwerman Islands", "datasets": [{"dataset_uid": "200389", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic ACROBAT data", "url": "https://www.bco-dmo.org/dataset/916046"}, {"dataset_uid": "200390", "doi": "10.26008/1912/bco-dmo.865030.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "CTD Data from IFCB Sampling", "url": "https://www.bco-dmo.org/dataset/865030"}, {"dataset_uid": "200391", "doi": "10.26008/1912/bco-dmo.917914.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Finite Time Lyapunov Exponent Results, Calculated from High Frequency Radar Observed Surface Currents", "url": "https://www.bco-dmo.org/dataset/917914"}, {"dataset_uid": "200392", "doi": "10.26008/1912/bco-dmo.917884.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "High Frequency Radar, Palmer Deep", "url": "https://www.bco-dmo.org/dataset/917884"}, {"dataset_uid": "200393", "doi": "10.26008/1912/bco-dmo.865002.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "IFCB Image Data", "url": "https://www.bco-dmo.org/dataset/865002"}, {"dataset_uid": "200394", "doi": "10.26008/1912/bco-dmo.917926.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Relative Particle Density", "url": "https://www.bco-dmo.org/dataset/917926"}, {"dataset_uid": "200395", "doi": "10.26008/1912/bco-dmo.872729.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "SWARM AMLR moorings - acoustic data", "url": "https://www.bco-dmo.org/dataset/872729"}, {"dataset_uid": "200396", "doi": "10.26008/1912/bco-dmo.867442.2", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "WAP model float data", "url": "https://www.bco-dmo.org/dataset/867442"}, {"dataset_uid": "200397", "doi": "10.26008/1912/bco-dmo.865098.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Winds from Joubin and Wauwerman Islands", "url": "https://www.bco-dmo.org/dataset/865098"}, {"dataset_uid": "200398", "doi": "", "keywords": null, "people": null, "repository": "IOOS Glider DAAC", "science_program": null, "title": "SWARM Glider Data near Palmer Deep", "url": "https://gliders.ioos.us/erddap/search/index.html?page=1\u0026itemsPerPage=1000\u0026searchFor=swarm"}], "date_created": "Tue, 05 Jul 2022 00:00:00 GMT", "description": "Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function. To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -55.0, "geometry": "POINT(-65 -65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CONDUCTIVITY SENSORS \u003e CONDUCTIVITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e RADIATION SENSORS", "is_usap_dc": true, "keywords": "MOORED; WATER TEMPERATURE; CONDUCTIVITY; FLUORESCENCE; UNCREWED VEHICLES; Palmer Station; PHOTOSYNTHETICALLY ACTIVE RADIATION; PELAGIC; OCEAN MIXED LAYER; SURFACE; SALINITY; WATER PRESSURE; LIVING ORGANISM; MODELS; ACOUSTIC SCATTERING", "locations": "Palmer Station", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems", "paleo_time": "NOT APPLICABLE", "persons": "Bernard, Kim; Oliver, Matthew; Kohut, Josh; Fraser, William; Klinck, John M.; Statcewich, Hank", "platforms": "LIVING ORGANISM-BASED PLATFORMS \u003e LIVING ORGANISM; OTHER \u003e MODELS; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED; WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE", "repo": "BCO-DMO", "repositories": "BCO-DMO; IOOS Glider DAAC", "science_programs": null, "south": -70.0, "title": "Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots", "uid": "p0010346", "west": -75.0}, {"awards": "1643669 Petrenko, Vasilii; 1643716 Buizert, Christo; 1643664 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((112 -66,112.2 -66,112.4 -66,112.6 -66,112.8 -66,113 -66,113.2 -66,113.4 -66,113.6 -66,113.8 -66,114 -66,114 -66.1,114 -66.2,114 -66.3,114 -66.4,114 -66.5,114 -66.6,114 -66.7,114 -66.8,114 -66.9,114 -67,113.8 -67,113.6 -67,113.4 -67,113.2 -67,113 -67,112.8 -67,112.6 -67,112.4 -67,112.2 -67,112 -67,112 -66.9,112 -66.8,112 -66.7,112 -66.6,112 -66.5,112 -66.4,112 -66.3,112 -66.2,112 -66.1,112 -66))", "dataset_titles": "Concentration and isotopic composition of atmospheric N2O over the last century; Law Dome DE08-OH firn air 15N, O2/N2, Ar/N2, 18O of O2; Law Dome DE08-OH site noble gases in ice: testing the 86Krexcess proxy; Law Dome firn air and ice core 14CO concentration", "datasets": [{"dataset_uid": "601846", "doi": "10.15784/601846", "keywords": "Antarctica; Carbon-14; Cryosphere; Firn Air; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Law Dome; Snow/ice; Snow/Ice", "people": "Petrenko, Vasilii", "repository": "USAP-DC", "science_program": null, "title": "Law Dome firn air and ice core 14CO concentration", "url": "https://www.usap-dc.org/view/dataset/601846"}, {"dataset_uid": "601598", "doi": "10.15784/601598", "keywords": "Antarctica; Firn; Firn Density; Gravitational Settling; Inert Gases; Law Dome", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Law Dome DE08-OH firn air 15N, O2/N2, Ar/N2, 18O of O2", "url": "https://www.usap-dc.org/view/dataset/601598"}, {"dataset_uid": "601597", "doi": "10.15784/601597", "keywords": "Antarctica; Ice Core; Law Dome; Noble Gas", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Law Dome DE08-OH site noble gases in ice: testing the 86Krexcess proxy", "url": "https://www.usap-dc.org/view/dataset/601597"}, {"dataset_uid": "601693", "doi": "10.15784/601693", "keywords": "Antarctic; Antarctica; Anthropogenic Emission; Atmosphere; Greenhouse Gas; Greenland; Ice Core Data; Nitrification And Denitrification Processes; Nitrous Oxide; Site-Specific 15N Isotopomer; Styx Glacier", "people": "Toyoda, Sakae ; Ghosh, Sambit; Etheridge, David; Ahn, Jinho ; Joong Kim, Seong; Yoshida, Naohiro ; Langenfelds, Ray L ; Buizert, Christo ", "repository": "USAP-DC", "science_program": null, "title": "Concentration and isotopic composition of atmospheric N2O over the last century", "url": "https://www.usap-dc.org/view/dataset/601693"}], "date_created": "Fri, 17 Jun 2022 00:00:00 GMT", "description": "Hydroxyl radicals are responsible for removal of most atmospheric trace gases, including pollutants and important greenhouse gases. They have been called the \"detergent of the atmosphere\". Changes in hydroxyl radical concentration in response to large changes in reactive trace gas emissions, which may happen in the future, are uncertain. This project aims to provide the first estimates of the variability of atmospheric hydroxyl radicals since about 1880 AD when anthropogenic emissions of reactive trace gases were minimal. This will improve understanding of their stability in response to large changes in emissions. The project will also investigate whether ice cores record past changes in Southern Hemisphere westerly winds. These winds are a key component of the global climate system, and have an important influence on ocean circulation and possibly on atmospheric carbon dioxide concentrations. The project team will include three early career scientists, a postdoctoral researcher, and graduate and undergraduate students, working in collaboration with senior scientists and Australian collaborators. Firn air and shallow ice to a depth of about 233 m will be sampled at the Law Dome high-accumulation coastal site in East Antarctica. Trapped air will be extracted from the ice cores on site immediately after drilling. Carbon-14 of carbon monoxide (14CO) will be analyzed in firn and ice-core air samples. Corrections will be made for the in situ cosmogenic 14CO component in the ice, allowing for the atmospheric 14CO history to be reconstructed. This 14CO history will be interpreted with the aid of a chemistry-transport model to place the first observational constraints on the variability of Southern Hemisphere hydroxyl radical concentration after about 1880 AD. An additional component of the project will analyze Krypton-86 in the firn-air and ice-core samples. These measurements will explore whether ice-core Krypton-86 acts as a proxy for barometric pressure variability, and whether this proxy can be used in Antarctic ice cores to infer past movement of the Southern Hemisphere westerly winds. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 114.0, "geometry": "POINT(113 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; TRACE GASES/TRACE SPECIES; Law Dome; Amd/Us; USAP-DC; LABORATORY; ICE CORE AIR BUBBLES; USA/NSF", "locations": "Law Dome", "north": -66.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Petrenko, Vasilii; Murray, Lee T; Buizert, Christo; Petrenko, Vasilii; Murray, Lee T", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability", "uid": "p0010341", "west": 112.0}, {"awards": "1745082 Beilman, David; 1745068 Booth, Robert", "bounds_geometry": "POLYGON((-64.4 -62.4,-63.910000000000004 -62.4,-63.42 -62.4,-62.93000000000001 -62.4,-62.440000000000005 -62.4,-61.95 -62.4,-61.46 -62.4,-60.97 -62.4,-60.480000000000004 -62.4,-59.99 -62.4,-59.5 -62.4,-59.5 -62.7,-59.5 -63,-59.5 -63.3,-59.5 -63.6,-59.5 -63.900000000000006,-59.5 -64.2,-59.5 -64.5,-59.5 -64.80000000000001,-59.5 -65.10000000000001,-59.5 -65.4,-59.99 -65.4,-60.480000000000004 -65.4,-60.97 -65.4,-61.46 -65.4,-61.95 -65.4,-62.440000000000005 -65.4,-62.93000000000001 -65.4,-63.42 -65.4,-63.910000000000004 -65.4,-64.4 -65.4,-64.4 -65.10000000000001,-64.4 -64.80000000000001,-64.4 -64.5,-64.4 -64.2,-64.4 -63.900000000000006,-64.4 -63.6,-64.4 -63.3,-64.4 -63,-64.4 -62.7,-64.4 -62.4))", "dataset_titles": "LMG2002 Expedtition Data", "datasets": [{"dataset_uid": "200222", "doi": "10.7284/908802", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG2002 Expedtition Data", "url": "https://www.rvdata.us/search/cruise/LMG2002"}], "date_created": "Fri, 10 Jun 2022 00:00:00 GMT", "description": "Warming on the western Antarctic Peninsula in the later 20th century has caused widespread changes in the cryosphere (ice and snow) and terrestrial ecosystems. These recent changes along with longer-term climate and ecosystem histories will be deciphered using peat deposits. Peat accumulation can be used to assess the rate of glacial retreat and provide insight into ecological processes on newly deglaciated landscapes in the Antarctic Peninsula. This project builds on data suggesting recent ecosystem transformations that are linked to past climate of the western Antarctic Peninsula and provide a timeline to assess the extent and rate of recent glacial change. The study will produce a climate record for the coastal low-elevation terrestrial region, which will refine the major climate shifts of up to 6 degrees C in the recent past (last 12,000 years). A novel terrestrial record of the recent glacial history will provide insight into observed changes in climate and sea-ice dynamics in the western Antarctic Peninsula and allow for comparison with off-shore climate records captured in sediments. Observations and discoveries from this project will be disseminated to local schools and science centers. The project provides training and career development for a postdoctoral scientist as well as graduate and undergraduate students. The research presents a new systematic survey to reconstruct ecosystem and climate change for the coastal low-elevation areas on the western Antarctic Peninsula (AP) using proxy records preserved in late Holocene peat deposits. Moss and peat samples will be collected and analyzed to generate a comprehensive data set of late-Holocene climate change and ecosystem dynamics. The goal is to document and understand the transformations of landscape and terrestrial ecosystems on the western AP during the late Holocene. The testable hypothesis is that coastal regions have experienced greater climate variability than evidenced in ice-core records and that past warmth has facilitated dramatic ecosystem and cryosphere response. A primary product of the project is a robust reconstruction of late Holocene climate changes for coastal low-elevation terrestrial areas using multiple lines of evidence from peat-based biological and geochemical proxies, which will be used to compare with climate records derived from marine sediments and ice cores from the AP region. These data will be used to test several ideas related to novel peat-forming ecosystems (such as Antarctic hairgrass bogs) in past warmer climates and climate controls over ecosystem establishment and migration to help assess the nature of the Little Ice Age cooling and cryosphere response. The chronology of peat cores will be established by radiocarbon dating of macrofossils and Bayesian modeling. The high-resolution time series of ecosystem and climate changes will help put the observed recent changes into a long-term context to bridge climate dynamics over different time scales. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -59.5, "geometry": "POINT(-61.95 -63.900000000000006)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; ISOTOPES; USAP-DC; PALEOCLIMATE RECONSTRUCTIONS; SEDIMENTS; Amd/Us; FIELD INVESTIGATION; Antarctic Peninsula; AMD; TERRESTRIAL ECOSYSTEMS; USA/NSF; RADIOCARBON", "locations": "Antarctic Peninsula", "north": -62.4, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Beilman, David; Booth, Robert", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.4, "title": "Collaborative Research: Reconstructing Late Holocene Ecosystem and Climate Shifts from Peat Records in the Western Antarctic Peninsula", "uid": "p0010337", "west": -64.4}, {"awards": "1643436 Donohoe, Aaron", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Partionining of CERES planetary albedo between atmospheric and surface reflection", "datasets": [{"dataset_uid": "601579", "doi": "10.15784/601579", "keywords": "Antarctica; Southern Ocean", "people": "Donohoe, Aaron", "repository": "USAP-DC", "science_program": null, "title": "Partionining of CERES planetary albedo between atmospheric and surface reflection", "url": "https://www.usap-dc.org/view/dataset/601579"}], "date_created": "Fri, 10 Jun 2022 00:00:00 GMT", "description": "This project will use observations and coupled climate model simulations to examine the causes of sea ice variability. Sea ice in the Southern Ocean has increased in area over the observational record but researchers have yet to agree on the cause. Researchers suggests that changes in surface winds, upper-ocean freshening, or internal ocean/atmosphere variability could be the main driver for the increase in sea ice area. This project will determine how much of the change in sea ice area from year to year is due to oceanic, atmospheric, and radiative processes. Reconciling the observation-based understanding with model representations of sea ice variability will improve confidence in projections of future changes in Southern Ocean sea ice. The goal of this proposal is to improve our understanding of the processes that drive Southern Ocean sea ice year-to-year variability and long term trends. This knowledge will provide insight into how Southern Ocean sea ice responded to greenhouse gas and ozone forcing in the past and how it will respond in the future. The energy budget of the coupled cryosphere/ocean/atmosphere climate system will be used as a framework to disentangle drivers and responses during sea ice loss events. The technique consists of: (i) calculating the coupled energy budget of the climate system at the monthly timescale, (ii) isolating the radiative impact of sea ice variability from the radiative impact of cloud variability in the observed satellite radiation record and (iii) analyzing the vertical structure of atmospheric energy transport to determine the vertical profile of energy transport into the atmospheric column. This framework will allow the investigators to distinguish whether ice loss events are triggered by oceanic processes, atmospheric dynamics, or radiative processes. Preliminary results show that a diversity of mechanisms can drive Southern Ocean sea ice variability in coupled climate models whereas observed sea ice variability appears to be dominated by atmospheric dynamics. The exploration of biases between models and observations in both the mean state and in specific processes will yield more accurate projections of the future of sea ice in the Southern Ocean.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; Amd/Us; SEA ICE; United States Of America; COMPUTERS; ATMOSPHERIC WINDS; ATMOSPHERIC RADIATION; NSF/USA", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Donohoe, Aaron; Schweiger, Axel", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "What Processes Drive Southern Ocean Sea Ice Variability and Trends? Insights from the Energy Budget of the Coupled Cryosphere-ocean-atmosphere System", "uid": "p0010336", "west": -180.0}, {"awards": "1951090 Stukel, Michael", "bounds_geometry": "POLYGON((-80 -63,-78.2 -63,-76.4 -63,-74.6 -63,-72.8 -63,-71 -63,-69.2 -63,-67.4 -63,-65.6 -63,-63.8 -63,-62 -63,-62 -63.7,-62 -64.4,-62 -65.1,-62 -65.8,-62 -66.5,-62 -67.2,-62 -67.9,-62 -68.6,-62 -69.3,-62 -70,-63.8 -70,-65.6 -70,-67.4 -70,-69.2 -70,-71 -70,-72.8 -70,-74.6 -70,-76.4 -70,-78.2 -70,-80 -70,-80 -69.3,-80 -68.6,-80 -67.9,-80 -67.2,-80 -66.5,-80 -65.8,-80 -65.1,-80 -64.4,-80 -63.7,-80 -63))", "dataset_titles": "BCO-DMO Project Page", "datasets": [{"dataset_uid": "200294", "doi": null, "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "BCO-DMO Project Page", "url": "https://www.bco-dmo.org/project/838048"}], "date_created": "Fri, 03 Jun 2022 00:00:00 GMT", "description": "Algae in the surface ocean convert carbon dioxide into organic carbon through photosynthesis. The biological carbon pump transports this organic carbon from the atmosphere to the deep ocean where it can be stored for tens to hundreds of years. Annually, the amount transported is similar to that humans are currently emitting by burning fossil fuels. However, at present we cannot predict how this important process will change with a warming ocean. These investigators plan to develop a 15+ year time-series of vertical carbon transfer for the Western Antarctic Peninsula; a highly productive Antarctic ecosystem. This region is also rapid transition to warmer temperatures leading to reduced sea ice coverage. This work will help researchers better understand how the carbon cycle in the Western Antarctic Peninsula will respond to climate change. The researchers will develop the first large-scale time-series of carbon flux anywhere in the ocean. This research will also support the education and training of a graduate student and support the integration of concepts in Antarctic research into two undergraduate courses designed for non-science majors and advanced earth science students. The researchers will also develop educational modules for introducing elementary and middle-school age students to important concepts such as gross and net primary productivity, feedbacks in the marine and atmospheric systems, and the differences between correlation and causation. Results from this proposal will also be incorporated into a children\u2019s book, \u201cPlankton do the Strangest Things\u201d, that is targeted at 5-7 year olds and is designed to introduce them to the incredible diversity and fascinating adaptations of microscopic marine organisms. This research seeks to leverage 6 years (2015-2020) of 234Th samples collected on Palmer LTER program, 5 years of prior measurements (2009-2010, 2012-2014), and upcoming cruises (2021-2023) to develop a time-series of summertime particle flux in the WAP that stretches for 15 years. The 238U-234Th disequilibrium approach utilizes changes in the activity of the particle-active radio-isotope 234Th relative to its parent nuclide 238U to quantify the flux of sinking carbon out of the surface ocean (over a time-scale of ~one month). This proposal will fund 234Th analyses from nine years\u2019 worth of cruises (2015-2023) and extensive analyses designed to investigate the processes driving inter-annual variability in the BCP. These include: 1) physical modeling to quantify the importance of advection and diffusion in the 234Th budget, 2) time-series analyses of particle flux, and 3) statistical modeling of the relationships between particle flux and multiple presumed drivers (biological, chemical, physical, and climate indices) measured by collaborators in the Palmer LTER program. This multi-faceted approach is critical for linking the measurements to models and for predicting responses to climate change. It will also test the hypothesis that export flux is decreasing in the northern WAP, increasing in the southern WAP, and increasing when integrated over the entire region as a result of earlier sea ice retreat and a larger ice-free zone. The project will also investigate relationships between carbon export and multiple potentially controlling factors including: primary productivity, algal biomass and taxonomic composition, biological oxygen saturation, zooplankton biomass and taxonomic composition, bacterial production, temperature, wintertime sea ice extent, date of sea ice retreat, and climate modes. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -62.0, "geometry": "POINT(-71 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; FIELD INVESTIGATION; Palmer Station; USAP-DC; BIOGEOCHEMICAL CYCLES; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Stukel, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -70.0, "title": "Quantifying Processes Driving Interannual Variability in the Biological Carbon Pump in the Western Antarctic Peninsula", "uid": "p0010332", "west": -80.0}, {"awards": "1543305 Lazzara, Matthew", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic Automatic Weather Station", "datasets": [{"dataset_uid": "200291", "doi": "https://doi.org/10.48567/1hn2-nw60", "keywords": null, "people": null, "repository": "AMRDC", "science_program": null, "title": "Antarctic Automatic Weather Station", "url": "https://amrdcdata.ssec.wisc.edu/group/about/automatic-weather-station-project"}], "date_created": "Mon, 16 May 2022 00:00:00 GMT", "description": "The Antarctic Automatic Weather Station (AWS) network is the most extensive ground meteorological network in the Antarctic, approaching its 30th year at several of its installations. Its prime focus as a long term observational record is to measure the near surface weather and climatology of the Antarctic atmosphere. AWS stations measure air-temperature, pressure, wind speed and direction at a nominal surface height of ~ 2-3m. Other parameters such as relative humidity and snow accumulation may also be taken. Observational data from the AWS are collected via Iridium network, or DCS Argos aboard either NOAA or MetOp polar orbiting satellites and thus made available in near real time to operational and synoptic weather forecasters. The surface observations from the AAWS network are important records for recent climate change and meteorological processes. The surface observations from the AAWS network are also used operationally, and in the planning of field work. The surface observations made from the AAWS network have been used to check on satellite and remote sensing observations. This project proposes to use the surface conditions observed by the AWS network to determine how large-scale modes of climate variability impact Antarctic weather and climate, how the surface observations from the AWS network are linked to surface layer and boundary layer processes, and to quantify the impact of snowfall and blowing snow events. Specifically, this project proposes to improve our understanding of the processes that lead to unusual weather events and how these events are related to large-scale modes of climate variability. This project will fill a gap in knowledge of snowfall distribution, and distinguishing between snowfall and blowing snow events using a suite of precipitation sensors near McMurdo Station.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "HUMIDITY; SURFACE PRESSURE; ATMOSPHERIC TEMPERATURE; AMD; ATMOSPHERIC PRESSURE; USA/NSF; AIR TEMPERATURE; Antarctica; USAP-DC; Amd/Us; SURFACE WINDS; SURFACE AIR TEMPERATURE; ATMOSPHERIC PRESSURE MEASUREMENTS; WEATHER STATIONS; ATMOSPHERIC WINDS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lazzara, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e WEATHER STATIONS", "repo": "AMRDC", "repositories": "AMRDC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Automatic Weather Station Program 2016-2019", "uid": "p0010319", "west": -180.0}, {"awards": "2146791 Lai, Chung Kei Chris", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 06 May 2022 00:00:00 GMT", "description": "Melt from the Greenland and Antarctic ice sheets is increasingly contributing to sea-level rise. This ice sheet mass loss is primarily driven by the thinning, retreat, and acceleration of glaciers in contact with the ocean. Observations from the field and satellites indicate that glaciers are sensitive to changes at the ice-ocean interface and that the increase in submarine melting is likely to be driven by the discharge of meltwater from underneath the glacier known as subglacial meltwater plumes. The melting of glacier ice also directly adds a large volume of freshwater into the ocean, potentially causing significant changes in the circulation of ocean waters that regulate global heat transport, making ice-ocean interactions an important potential factor in climate change and variability. The ability to predict, and hence adequately respond to, climate change and sea-level rise therefore depends on our knowledge of the small-scale processes occurring in the vicinity of subglacial meltwater plumes at the ice-ocean interface. Currently, understanding of the underlying physics is incomplete; for example, different models of glacier-ocean interaction could yield melting rates that vary over a factor of five for the same heat supply from the ocean. It is then very difficult to assess the reliability of predictive models. This project will use comprehensive laboratory experiments to study how the melt rates of glaciers in the vicinity of plumes are affected by the ice roughness, ice geometry, ocean turbulence, and ocean density stratification at the ice-ocean interface. These experiments will then be used to develop new and improved predictive models of ice-sheet melting by the ocean. This project builds bridges between modern experimental fluid mechanics and glaciology with the goal of leading to advances in both fields. As a part of this work, two graduate students will receive interdisciplinary training and each year two undergraduate students will be trained in experimental fluid mechanics to assist in this work and develop their own research projects. This project consists of a comprehensive experimental program designed for studying the melt rates of glacier ice under the combined influences of (1) turbulence occurring near and at the ice-ocean interface, (2) density stratification in the ambient water column, (3) irregularities in the bottom topology of an ice shelf, and (4) differing spatial distributions of multiple meltwater plumes. The objective of the experiments is to obtain high-resolution data of the velocity, density, and temperature near/at the ice-ocean interface, which will then be used to improve understanding of melt processes down to scales of millimeters, and to devise new, more robust numerical models of glacier evolution and sea-level rise. Specially, laser-based, optical techniques in experimental fluid mechanics (particle image velocity and laser-induced fluorescence) will be used to gather the data, and the experiments will be conducted using refractive-index matching techniques to eliminate changes in refractive indices that could otherwise bias the measurements. The experiments will be run inside a climate-controlled cold room to mimic field conditions (ocean temperature from 0-10 degrees C). The project will use 3D-printing to create different casting molds for making ice blocks with different types of roughness. The goal is to investigate how ice melt rate changes as a function of the properties of the plume, the ambient ocean water, and the geometric properties of the ice interface. Based on the experimental findings, this project will develop and test a new integral-plume-model coupled to a regional circulation model (MITgcm) that can be used to predict the effects of glacial melt on ocean circulation and sea-level rise. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Glacier-Ocean Boundary Layer; Alaska; USAP-DC; USA/NSF; ABLATION ZONES/ACCUMULATION ZONES; GLACIERS; AMD; Amd/Us; Antarctica; LABORATORY", "locations": "Antarctica; Alaska", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Lai, Chung; Robel, Alexander", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Revising Models of the Glacier-Ocean Boundary Layer with Novel Laboratory Experiments ", "uid": "p0010317", "west": null}, {"awards": "2046260 Salvatore, Mark; 2045880 Sokol, Eric", "bounds_geometry": "POLYGON((161.88 -77.47,162.075 -77.47,162.27 -77.47,162.465 -77.47,162.66 -77.47,162.855 -77.47,163.05 -77.47,163.245 -77.47,163.44 -77.47,163.635 -77.47,163.83 -77.47,163.83 -77.501,163.83 -77.532,163.83 -77.563,163.83 -77.594,163.83 -77.625,163.83 -77.656,163.83 -77.687,163.83 -77.718,163.83 -77.749,163.83 -77.78,163.635 -77.78,163.44 -77.78,163.245 -77.78,163.05 -77.78,162.855 -77.78,162.66 -77.78,162.465 -77.78,162.27 -77.78,162.075 -77.78,161.88 -77.78,161.88 -77.749,161.88 -77.718,161.88 -77.687,161.88 -77.656,161.88 -77.625,161.88 -77.594,161.88 -77.563,161.88 -77.532,161.88 -77.501,161.88 -77.47))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 21 Apr 2022 00:00:00 GMT", "description": "Part I: Non-technical description: Water is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a new method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training of high-school curricular programming in Native American communities of the SouthWest. Part II: Technical description: Terrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from native American communities in the SouthWest where similar desert conditions exist. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 163.83, "geometry": "POINT(162.855 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "ACTIVE LAYER; Taylor Valley; USAP-DC; Amd/Us; AMD; MODELS; USA/NSF", "locations": "Taylor Valley", "north": -77.47, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -77.78, "title": "Collaborative Research: Moving Beyond the Margins: Modeling Water Availability and Habitable Terrestrial Ecosystems in the Polar Desert of the McMurdo Dry Valleys", "uid": "p0010316", "west": 161.88}, {"awards": "1643534 Cassar, Nicolas", "bounds_geometry": "POLYGON((-83 -62,-80.3 -62,-77.6 -62,-74.9 -62,-72.2 -62,-69.5 -62,-66.8 -62,-64.1 -62,-61.4 -62,-58.7 -62,-56 -62,-56 -63.1,-56 -64.2,-56 -65.3,-56 -66.4,-56 -67.5,-56 -68.6,-56 -69.7,-56 -70.8,-56 -71.9,-56 -73,-58.7 -73,-61.4 -73,-64.1 -73,-66.8 -73,-69.5 -73,-72.2 -73,-74.9 -73,-77.6 -73,-80.3 -73,-83 -73,-83 -71.9,-83 -70.8,-83 -69.7,-83 -68.6,-83 -67.5,-83 -66.4,-83 -65.3,-83 -64.2,-83 -63.1,-83 -62))", "dataset_titles": "Palmer LTER 18S rRNA gene metabarcodin; rDNA amplicon sequencing of WAP microbial community", "datasets": [{"dataset_uid": "200286", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "rDNA amplicon sequencing of WAP microbial community", "url": "https://www.ncbi.nlm.nih.gov/sra/SRR6162326/"}, {"dataset_uid": "200285", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "Palmer LTER 18S rRNA gene metabarcodin", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA508517"}], "date_created": "Thu, 03 Mar 2022 00:00:00 GMT", "description": "This project seeks to make detailed measurements of the oxygen content of the surface ocean along the Western Antarctic Peninsula. Detailed maps of changes in net oxygen content will be combined with measurements of the surface water chemistry and phytoplankton distributions. The project will determine the extent to which on-shore or offshore phytoplankton blooms along the peninsula are likely to lead to different amounts of carbon being exported to the deeper ocean. The project team members will participate in the development of new learning tools at the Museum of Life and Science. They will also teach secondary school students about aquatic biogeochemistry and climate, drawing directly from the active science supported by this grant. The project will analyze oxygen in relation to argon that will allow determination of the physical and biological contributions to surface ocean oxygen dynamics. These assessments will be combined with spatial and temporal distributions of nutrients (iron and macronutrients) and irradiances. This will allow the investigators to unravel the complex interplay between ice dynamics, iron and physical mixing dynamics as they relate to Net Community Production (NCP) in the region. NCP measurements will be normalized to Particulate Organic Carbon (POC) and be used to help identify area of \"High Biomass and Low NCP\" and those with \"Low Biomass and High NCP\" as a function of microbial plankton community composition. The team will use machine learning methods- including decision tree assemblages and genetic programming- to identify plankton groups key to facilitating biological carbon fluxes. Decomposing the oxygen signal along the West Antarctic Peninsula will also help elucidate biotic and abiotic drivers of the O2 saturation to further contextualize the growing inventory of oxygen measurements (e.g. by Argo floats) throughout the global oceans.", "east": -56.0, "geometry": "POINT(-69.5 -67.5)", "instruments": null, "is_usap_dc": true, "keywords": "West Antarctica; USAP-DC; BIOGEOCHEMICAL CYCLES; AMD; USA/NSF; LABORATORY; Amd/Us", "locations": "West Antarctica", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cassar, Nicolas", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "NCBI", "repositories": "NCBI", "science_programs": null, "south": -73.0, "title": "Biological and Physical Drivers of Oxygen Saturation and Net Community Production Variability along the Western Antarctic Peninsula", "uid": "p0010303", "west": -83.0}, {"awards": "1744998 Fogt, Ryan; 1745089 Raphael, Marilyn", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic Sea Ice Reconstructions", "datasets": [{"dataset_uid": "200261", "doi": "https://doi.org/10.6084/m9.figshare.c.5709767.v1", "keywords": null, "people": null, "repository": "Figshare", "science_program": null, "title": "Antarctic Sea Ice Reconstructions", "url": "https://figshare.com/collections/Antarctic_Sea_Ice_Reconstructions/5709767"}], "date_created": "Fri, 10 Dec 2021 00:00:00 GMT", "description": "In contrast to the Arctic, sea ice cover in most Antarctic regions has increased since 1979. The area-integrated total sea ice extent grew to record maximum values in four of the last six years, yet the 2015-16 summer was marked by record low ice cover. While impressive, it is difficult to assess the significance of these very recent records in the context of longer term variability, since the continuous satellite record only dates back to 1978. The limited length of the continuous sea ice record, is a significant confounding factor in ascertaining whether the observed current changes are due to natural variability alone, or represent a forced anthropogenic response. As a result, the scientific understanding of the Antarctic sea ice trends remains poor, as does confidence in projections of future Antarctic sea ice trends. To address this challenge, this project seeks to reconstruct sea ice extent and sea ice concentration, using the relationships between satellite-observed sea ice, sea level pressure, tropical sea surface temperature, ENSO indices, some proxy data (ice cores, etc.), and in situ Southern Ocean temperature data. The aim of the study is to collect and combine these ancillary records as accurately as possible while retaining the variability associated with the intrinsic uncertainty in the available field data. A range of statistical methods for modelling the relationship between satellite era sea-ice data using flexible regression, Bayesian and multivariate dynamic spatial temporal (MDST) methods will be used. The study will entrain cross-disciplinary training of undergraduate and a graduate student at UCLA and Ohio University. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; Antarctica; NOT APPLICABLE; Amd/Us; SEA ICE; USAP-DC; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Fogt, Ryan", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "Figshare", "repositories": "Figshare", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Understanding Contemporary Variability in Antarctic Sea Ice: Ensemble Reconstruction of Sea Ice Extent and Concentration for the 20th Century", "uid": "p0010284", "west": -180.0}, {"awards": "1951500 Jenouvrier, Stephanie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Data from: Individual life histories: Neither slow nor fast, just diverse; Evo-Demo Hyperstate Matrix Model Code Repository; Hyperstate matrix model reveals the influence of personality on demography; Individual life histories: neither slow nor fast, just diverse; Plastic Behaviour Buffers Climate Variability in the Wandering Albatross; Strong winds reduce foraging success in albatrosses; Subtropical anticyclone impacts life-history traits of a marine top predator; The impact of boldness on demographic rates and lifehistory outcomes in the wandering albatross", "datasets": [{"dataset_uid": "200458", "doi": "https://doi.org/10.5061/dryad.3bk3j9kpm", "keywords": null, "people": null, "repository": "DRYAD", "science_program": null, "title": "Individual life histories: neither slow nor fast, just diverse", "url": "https://doi.org/10.6084/m9.figshare.c.6181063."}, {"dataset_uid": "200459", "doi": "https://doi.org/10.5281/zenodo.13881532", "keywords": null, "people": null, "repository": "ZENODO", "science_program": null, "title": "Strong winds reduce foraging success in albatrosses", "url": "https://zenodo.org/records/13881532"}, {"dataset_uid": "601770", "doi": "10.15784/601770", "keywords": "Antarctica; Cryosphere; Demography; Sub-Antarctic", "people": "Joanie, Van de Walle; Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "The impact of boldness on demographic rates and lifehistory outcomes in the wandering albatross", "url": "https://www.usap-dc.org/view/dataset/601770"}, {"dataset_uid": "200453", "doi": "10.5061/dryad.3bk3j9kpm", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Individual life histories: Neither slow nor fast, just diverse", "url": "https://doi.org/10.5061/dryad.3bk3j9kpm"}, {"dataset_uid": "200454", "doi": "", "keywords": null, "people": null, "repository": "GITHUB", "science_program": null, "title": "Evo-Demo Hyperstate Matrix Model Code Repository", "url": "https://github.com/fledge-whoi/Eco-EvoHyperstateModel"}, {"dataset_uid": "200455", "doi": "", "keywords": null, "people": null, "repository": "GITHUB", "science_program": null, "title": "Hyperstate matrix model reveals the influence of personality on demography", "url": "https://github.com/fledge-whoi/HyperstateWApopulationmodel"}, {"dataset_uid": "200456", "doi": "", "keywords": null, "people": null, "repository": "GITHUB", "science_program": null, "title": "Subtropical anticyclone impacts life-history traits of a marine top predator", "url": "https://github.com/fledge-whoi/Alba_Mascarene-High"}, {"dataset_uid": "200457", "doi": " https://zenodo.org/doi/10.5281/zenodo.10887354", "keywords": null, "people": null, "repository": "ZENODO", "science_program": null, "title": "Plastic Behaviour Buffers Climate Variability in the Wandering Albatross", "url": "https://zenodo.org/records/14290546"}], "date_created": "Wed, 08 Dec 2021 00:00:00 GMT", "description": "Part I: Nontechnical description: This award represents a collaborative geoscience research effort between US NSF and UK Natural Environment Research Council (NERC) researchers with efforts in each nation funded by their respective countries (Dear Colleague Letter NSF 16-132). The research will focus on understanding the links between behavior, ecology, and evolution in a Southern Ocean wandering albatross population in response to global changes in climate and in exploitation of natural resources. The most immediate response of animals to global change typically is behavioral, and this work will provide a more comprehensive understanding of how differences individual bird behavior affect evolution and adaptation for the population under changing environments. Characterization of albatross personality, life-history traits, and population dynamics collected over long time scales will be used to develop robust forecasting of species persistence in the face of future global changes. The results of this project will feed into conservation and management decisions for endangered Southern Ocean species. The work will also be used to provide specific research training at all levels, including a postdoctoral scholar, graduate students and K-12 students. It will also support education for the public about impacts from human-induced activities on our polar ecosystems using animations, public lectures, printed and web media. Part II: Technical description Past research has shown that individual animal personalities range over a continuum of behavior, such that some individuals are consistently more aggressive, more explorative, and bolder than others. How the phenotypic distributions of personality and foraging behavior types within a population is created and maintained by ecological (demographic and phenotypic plasticity) and evolutionary (heritability) processes remain an open question. Differences in personality traits determine how individuals acquire resources and how they allocate these to reproduction and survival. Although some studies have found different foraging behaviors or breeding performances between personality types, none have established the link between personality differences in foraging behaviors and life histories (both reproduction and survival, and their covariations) in the context of global change. Furthermore, plasticity in foraging behaviors is not considered in the pace-of-life syndrome, which has potentially hampered our ability to find covariation between personality and life history trade-off. This project will fill these knowledge gaps and develop an eco-evolutionary model of the complex interactions among individual personality and foraging plasticity, heritability of personality and foraging behaviors, life history strategies, population dynamics in a changing environment (fisheries and climate) using a long-term database consisting of ~1,800 tagged wandering albatross seabirds (Diomedea exulans) with defined individual personalities and life history traits breeding in the Southern Ocean. Climate projections from IPCC atmospheric-oceanic global circulation models will be used to provide projections of population structure under future global change conditions. Specifically, the team will (1) characterize the differences in life history strategies along the shy-bold continuum of personalities and across environmental conditions; (2) develop the link between phenotypic plasticity in foraging effort and personality; (3) characterize the heritability of personality and foraging behaviors; (4) develop a stochastic eco-evolutionary model to predict population growth rates in a changing environment. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE; AMD; ECOLOGICAL DYNAMICS; OCEAN TEMPERATURE; USA/NSF; Antarctica; SPECIES/POPULATION INTERACTIONS; PENGUINS; Amd/Us", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Jenouvrier, Stephanie; Patrick, Samantha", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "DRYAD", "repositories": "Dryad; DRYAD; GITHUB; USAP-DC; ZENODO", "science_programs": null, "south": -90.0, "title": "NSFGEO-NERC: Integrating Individual Personality Differences in the Evolutionary Ecology of a Seabird in the Rapidly Changing Polar Environment", "uid": "p0010283", "west": -180.0}, {"awards": "2139051 Guitard, Michelle", "bounds_geometry": "POLYGON((-45 -57,-44.3 -57,-43.6 -57,-42.9 -57,-42.2 -57,-41.5 -57,-40.8 -57,-40.1 -57,-39.4 -57,-38.7 -57,-38 -57,-38 -57.5,-38 -58,-38 -58.5,-38 -59,-38 -59.5,-38 -60,-38 -60.5,-38 -61,-38 -61.5,-38 -62,-38.7 -62,-39.4 -62,-40.1 -62,-40.8 -62,-41.5 -62,-42.2 -62,-42.9 -62,-43.6 -62,-44.3 -62,-45 -62,-45 -61.5,-45 -61,-45 -60.5,-45 -60,-45 -59.5,-45 -59,-45 -58.5,-45 -58,-45 -57.5,-45 -57))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 05 Nov 2021 00:00:00 GMT", "description": "Antarctic Ice Sheet stability remains a large uncertainty in predicting future sea level. Presently, the greatest ice mass loss is observed in locations where relatively warm water comes into contact with glaciers and ice shelves, melting them from below. This has led researchers to hypothesize that the interactions that occur between the ocean and the ice are important for determining ice sheet stability and that increased warm water presence will accelerate Antarctic ice mass loss and lead to greater sea level rise in the coming century. To better predict future ice sheet behavior, it is critical to understand past ice-ocean interactions around Antarctica, especially during warm periods and at times when Earth\u2019s climate was undergoing major changes. Past Antarctic ice mass and environmental conditions like ocean temperature can be reconstructed using sediments, which capture an environmental record as they accumulate on the ocean floor. By looking at sediment composition and by analyzing geochemical signatures within the sediment, it is possible to piece together a record of climate change on hundred- to million-year timescales. This project will reconstruct upper ocean temperatures and Antarctic ice retreat/advance cycles from 2.6 to 0.7 million years ago, which encompasses the Mid-Pleistocene Transition, a time in Earth\u2019s history that marks the shift from 41-thousand year glacial cycles to 100-thousand year glacial cycles. A record will be generated from existing sediment cores collected from the Scotia Sea during International Ocean Discovery Program Expedition 382. The Mid-Pleistocene Transition (MPT; ~1.25\u20130.7 Ma) marks the shift from glacial-interglacial cycles paced by obliquity (~41 kyr cycles) to those paced by eccentricity (~100-kyr cycles). This transition occurred despite little variation in Earth\u2019s orbital parameters, suggesting a role for internal climate feedbacks. The MPT was accompanied by decreasing atmospheric pCO2, increasing deep ocean carbon storage, and changes in deep water formation and distribution, all of which are linked to Antarctic margin atmosphere-ice-ocean interactions. However, Pleistocene records that document such interactions are rarely preserved on the shelf due to repeated Antarctic Ice Sheet (AIS) advance; instead, they are preserved in deep Southern Ocean basins. This project takes advantage of the excellent preservation and recovery of continuous Pleistocene sediment sequences collected from the Scotia Sea during International Ocean Discovery Program Expedition 382 to test the following hypotheses: 1) Southern Ocean upper ocean temperatures vary on orbital timescales during the early to middle Pleistocene (2.6\u20130.7 Ma), and 2) Southern Ocean temperatures co-vary with AIS advance/retreat cycles. Paleotemperatures will be reconstructed using the TetraEther indeX of 86 carbons (TEX86), a proxy that utilizes marine archaeal biomarkers. The Scotia Sea TEX86-based paleotemperature record will be compared to records of AIS variability, including ice rafted debris. Expedition 382 records will be compared to orbitally paced climatic time series and the benthic oxygen isotope record of global ice volume and bottom water temperature to determine if a correlation exists between upper ocean temperature, AIS retreat/advance, and orbital climate forcing. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -38.0, "geometry": "POINT(-41.5 -59.5)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; SEA SURFACE TEMPERATURE; USAP-DC; USA/NSF; LABORATORY; AMD; Scotia Sea", "locations": "Scotia Sea", "north": -57.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Michelle, Guitard", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -62.0, "title": "Investigating the influence of ocean temperature on Antarctic Ice Sheet evolution during the early to middle Pleistocene ", "uid": "p0010275", "west": -45.0}, {"awards": "2035580 Aarons, Sarah; 2035637 Tabor, Clay", "bounds_geometry": null, "dataset_titles": "Concentration and flux of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area; Oxygen and hydrogen isotope compositions and associated d-excess of ice from ALHIC1903 drilled at the Allan Hills Blue Ice Area.; Rare earth elemental concentrations of leached ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.; Strontium and neodymium isotope compositions of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "datasets": [{"dataset_uid": "601822", "doi": "10.15784/601822", "keywords": "ALHIC1903; Allan Hills; Antarctica; Cryosphere; Deuterium; Hydrogen; Ice; Ice Core Data; Isotope; Oxygen; Water", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Oxygen and hydrogen isotope compositions and associated d-excess of ice from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601822"}, {"dataset_uid": "601821", "doi": "10.15784/601821", "keywords": "ALHIC1903; Allan Hills; Antarctica; Blue Ice; Cryosphere; Dust; Leach; Rare Earth Element", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Rare earth elemental concentrations of leached ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601821"}, {"dataset_uid": "601820", "doi": "10.15784/601820", "keywords": "ALHIC1903; Allan Hills; Antarctica; Cryosphere; Dust; Ice Core Data; Isotope; Nd; Neodymium; Sr; Strontium", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": null, "title": "Strontium and neodymium isotope compositions of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area.", "url": "https://www.usap-dc.org/view/dataset/601820"}, {"dataset_uid": "601825", "doi": "10.15784/601825", "keywords": "Accumulation Rate; ALHIC1903; Allan Hills; Antarctica; Blue Ice; Concentration; Cryosphere; Dust; Flux", "people": "Carter, Austin", "repository": "USAP-DC", "science_program": null, "title": "Concentration and flux of ice core dust from ALHIC1903 drilled at the Allan Hills Blue Ice Area", "url": "https://www.usap-dc.org/view/dataset/601825"}], "date_created": "Wed, 06 Oct 2021 00:00:00 GMT", "description": "This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The spatial extent of the West Antarctic Ice Sheet during the last interglacial period (129,000 to 116,000 years ago) is currently unknown, yet this information is fundamental to projections of the future stability of the ice sheet in a warming climate. Paleoclimate records and proxy evidence such as dust can inform on past environmental conditions and ice-sheet coverage. This project will combine new, high-sensitivity geochemical measurements of dust from Antarctic ice collected at Allan Hills with existing water isotope records to document climate and environmental changes through the last interglacial period. These changes will then be compared with Earth-system model simulations of dust and water isotopes to determine past conditions and constrain the sensitivity of the West Antarctic Ice Sheet to warming. The project will test the hypothesis that the uncharacteristically volcanic dust composition observed at another peripheral ice core site at Taylor Glacier during the last interglacial period is related to changes in the spatial extent of the West Antarctic Ice Sheet. This project aims to characterize mineral dust transport during the penultimate glacial-interglacial transition. The team will apply high-precision geochemical techniques to the high-volume, high-resolution ice core drilled at the Allan Hills site in combination with Earth system model simulations to: (1) determine if the volcanic dust signature found in interglacial ice from Taylor Glacier is also found at Allan Hills, (2) determine the likely dust source(s) to this site during the last interglacial, and (3) probe the atmospheric and environmental changes during the last interglacial with a diminished West Antarctic Ice Sheet. The team will develop a suite of measurements on previously drilled ice from Allan Hills, including isotopic compositions of Strontium and Neodymium, trace element concentrations, dust-size distribution, and imaging of ice-core dust to confirm the original signal observed and provide a broader spatial reconstruction of dust transport. In tandem, the team will conduct Earth system modeling with prognostic dust and water-isotope capability to test the sensitivity of dust transport under several plausible ice-sheet and freshwater-flux configurations. By comparing dust reconstruction and model simulations, the team aims to elucidate the driving mechanisms behind dust transport during the last interglacial period. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MICROPARTICLE CONCENTRATION; FIELD SURVEYS; GEOCHEMISTRY; ICE EXTENT; Amd/Us; USA/NSF; PALEOCLIMATE RECONSTRUCTIONS; AMD; Allan Hills; ICE CORE RECORDS; USAP-DC", "locations": "Allan Hills", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Aarons, Sarah; Tabor, Clay", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Peripheral East Antarctic ice as a unique recorder of climate variability during the Last Interglacial", "uid": "p0010270", "west": null}, {"awards": "2049332 Chu, Wing Yin", "bounds_geometry": "POLYGON((-180 -75,-175 -75,-170 -75,-165 -75,-160 -75,-155 -75,-150 -75,-145 -75,-140 -75,-135 -75,-130 -75,-130 -76.1,-130 -77.2,-130 -78.3,-130 -79.4,-130 -80.5,-130 -81.6,-130 -82.7,-130 -83.8,-130 -84.9,-130 -86,-135 -86,-140 -86,-145 -86,-150 -86,-155 -86,-160 -86,-165 -86,-170 -86,-175 -86,180 -86,177.5 -86,175 -86,172.5 -86,170 -86,167.5 -86,165 -86,162.5 -86,160 -86,157.5 -86,155 -86,155 -84.9,155 -83.8,155 -82.7,155 -81.6,155 -80.5,155 -79.4,155 -78.3,155 -77.2,155 -76.1,155 -75,157.5 -75,160 -75,162.5 -75,165 -75,167.5 -75,170 -75,172.5 -75,175 -75,177.5 -75,-180 -75))", "dataset_titles": "Frozen Legacies - This repository hosts scientific journals and processing codes via Python and MATLab for the historical SPRI-NSF-TUD Campaign in Antarctica.", "datasets": [{"dataset_uid": "200466", "doi": "", "keywords": null, "people": null, "repository": "Frozen Legacies ", "science_program": null, "title": "Frozen Legacies - This repository hosts scientific journals and processing codes via Python and MATLab for the historical SPRI-NSF-TUD Campaign in Antarctica.", "url": "https://github.com/tarzona/frozenlegacies"}], "date_created": "Wed, 15 Sep 2021 00:00:00 GMT", "description": "This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Ice shelves play a critical role in restricting the seaward flow of grounded glacier ice by providing buttressing at their bases and sides. Processes that affect the long-term stability of ice shelves can therefore influence the future contribution of the Antarctic Ice Sheet to global sea-level rise. The Ross Ice Shelf is the largest ice shelf on Earth, and it buttresses massive areas of West and East Antarctica. Previous studies of modern ice velocity indicated that the Ross Ice Shelf\u2019s mass loss is roughly balanced by its mass gain. However, more recent work that extends further back in time reveals the ice shelf is likely not in steady state, with possible long-term thinning since the late 1990s. Consequently, to accurately interpret modern-day ice-shelf changes, long-term observations are critical to evaluate how these recent variations fit into the historical context of ice-shelf variability. This project will examine more than four decades of historical and modern airborne radar sounding observations of the Ross Ice Shelf (spanning 1971 to 2017) to investigate ice-shelf changes on decadal timescales. The team will process, calibrate, and analyze radar data collected during 1971-79 field campaigns and compare them against modern observations collected between 2011-17. They will estimate basal melt rates by examining changes in ice-shelf thickness, and will determine other important metrics for melt, including ice-shelf roughness, englacial temperature, and marine-ice formation. The project will support the education of a Ph.D. student at each of the three participating institutions. In addition, the project will support the training of undergraduate and high-school researchers in radioglaciology and Antarctic sciences. The project will test the hypothesis that, over decadal timescales, the basal melt rates beneath the Ross Ice Shelf have been low, particularly under shallow ice drafts, leading to overall thickening and increased buttressing potential. The team aims to provide a direct estimate of basal melt rates based on changes in ice-shelf thickness that occurred between 1971 and 2017. This project will extend similar work completed at Thwaites Glacier and improve the calibration methods on the vertical scaling for fast-time and depth conversion. The work will also leverage the dense modern surveys to improve the geolocation of radar film collected on earlier field campaigns to produce a more precise comparison of local shelf thickness with the modern data. In addition, the team will conduct englacial attenuation analysis to calculate englacial temperature to infer the trends in local basal melting. They will also examine the radiometric and scatterometric character of bed echoes at the ice-ocean boundary to characterize changes in ice-shelf basal roughness, marine-ice formation related to local basal freezing, and structural damage from fracture processes. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -130.0, "geometry": "POINT(-167.5 -80.5)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; Antarctic Ice Sheet; GLACIER THICKNESS/ICE SHEET THICKNESS; USAP-DC; AMD; Transantarctic Mountains; Amd/Us; Siple Coast; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; FIELD SURVEYS; USA/NSF; Ross Ice Shelf", "locations": "Ross Ice Shelf; Antarctic Ice Sheet; Siple Coast; Transantarctic Mountains", "north": -75.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Chu, Winnie; Schroeder, Dustin; Siegfried, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "Frozen Legacies ", "repositories": "Frozen Legacies ", "science_programs": null, "south": -86.0, "title": "Collaborative Research: Investigating Four Decades of Ross Ice Shelf Subsurface Change with Historical and Modern Radar Sounding Data", "uid": "p0010265", "west": 155.0}, {"awards": "2114786 Warnock, Jonathan", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 Sep 2021 00:00:00 GMT", "description": "The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica\u2019s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica\u2019s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth\u0027s most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change. The proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica\u2019s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "MICROFOSSILS; FIELD SURVEYS; Weddell Sea Embayment; USA/NSF; SEA ICE; USAP-DC; PALEOCLIMATE RECONSTRUCTIONS; SEA SURFACE TEMPERATURE; AMD; Amd/Us", "locations": "Weddell Sea Embayment", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Warnock, Jonathan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Linking Marine and Terrestrial Sedimentary Evidence for Plio-pleistocene Variability of Weddell Embayment and Antarctic Peninsula Glaciation", "uid": "p0010260", "west": null}, {"awards": "2103032 Schmittner, Andreas", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 Sep 2021 00:00:00 GMT", "description": "This project investigates Antarctic ice-ocean interactions of the last 20,000 years. The Antarctic ice sheet is an important component of Earth\u2019s climate system, as it interacts with the atmosphere, the surrounding Southern Ocean, and the underlaying solid Earth. The ice sheet is also the largest potential contributor to future sea-level rise and a major uncertainty in climate projections. Climate change may trigger instabilities that may lead to fast and irreversible collapse of parts of the ice sheet. However, little is known about how interactions between the Antarctic ice sheet and the rest of the climate system affect its behavior, climate, and sea level, partly because most climate models currently do not have fully-interactive ice-sheet components. The project team will construct a numerical climate model that includes an interactive Antarctic ice sheet, improving computational infrastructure for research. The model code will be made freely available to the public on a code-sharing site. In addition, the team will synthesize paleoclimate data and compare these with model simulations. This model-data comparison will test three scientific hypotheses regarding past changes in deep-ocean circulation, ice sheet, carbon, and sea level. The project will contribute to a better understanding of ice-ocean interactions and past climate variability. The project will test ideas that ice-ocean interactions have been important for setting deep ocean circulation and carbon storage during the Last Glacial Maximum and subsequent deglaciation. The new model will consist of three existing and well-tested components: (1) an isotope-enabled climate-carbon cycle model of intermediate complexity; (2) a model of the combined Antarctic ice sheet, solid Earth, and sea level; and (3) an iceberg model. The coupling will include ocean-temperature effects on basal melting of ice shelves; freshwater fluxes from the ice sheet to the ocean; and calving, transport and melting of icebergs. Once constructed and optimized, the model will be applied to simulate the Last Glacial Maximum and subsequent deglaciation. Differences between model versions with full, partial, or no coupling will be used to investigate the effects of ice-ocean interactions on the Meridional Overturning Circulation, deep ocean carbon storage, and ice-sheet fluctuations. Paleoclimate data synthesis will include temperature, carbon and nitrogen isotopes, radiocarbon ages, protactinium-thorium ratios, neodymium isotopes, carbonate ion, dissolved oxygen, relative sea level, and terrestrial cosmogenic ages into one multi-proxy database with a consistent updated chronology. The project will support an early-career scientist, one graduate student, undergraduate students, and new and ongoing national and international collaborations. Outreach activities in collaboration with a local science museum will benefit rural communities in Oregon by improving their climate literacy. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "ICE CORE RECORDS; Amd/Us; USA/NSF; OCEAN TEMPERATURE; GLACIERS/ICE SHEETS; BIOGEOCHEMICAL CYCLES; MODELS; AMD; United States Of America; OCEAN CURRENTS; ICEBERGS; PALEOCLIMATE RECONSTRUCTIONS", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Schmittner, Andreas; Haight, Andrew ; Clark, Peter", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Investigating Antarctic Ice Sheet-Ocean-Carbon Cycle Interactions During the Last Deglaciation", "uid": "p0010256", "west": -180.0}, {"awards": "0838843 Kurbatov, Andrei; 1744993 Higgins, John; 1744832 Severinghaus, Jeffrey; 1745007 Mayewski, Paul; 1745006 Brook, Edward J.", "bounds_geometry": "POLYGON((159.16667 -76.66667,159.19167 -76.66667,159.21667 -76.66667,159.24167 -76.66667,159.26667 -76.66667,159.29167 -76.66667,159.31667 -76.66667,159.34167 -76.66667,159.36667 -76.66667,159.39167 -76.66667,159.41667 -76.66667,159.41667 -76.673336,159.41667 -76.680002,159.41667 -76.686668,159.41667 -76.693334,159.41667 -76.7,159.41667 -76.706666,159.41667 -76.713332,159.41667 -76.719998,159.41667 -76.726664,159.41667 -76.73333,159.39167 -76.73333,159.36667 -76.73333,159.34167 -76.73333,159.31667 -76.73333,159.29167 -76.73333,159.26667 -76.73333,159.24167 -76.73333,159.21667 -76.73333,159.19167 -76.73333,159.16667 -76.73333,159.16667 -76.726664,159.16667 -76.719998,159.16667 -76.713332,159.16667 -76.706666,159.16667 -76.7,159.16667 -76.693334,159.16667 -76.686668,159.16667 -76.680002,159.16667 -76.673336,159.16667 -76.66667))", "dataset_titles": "Allan Hills 2022-23 Shallow Ice Core Field Report; Allan Hills CMC3 ice core d18Oatm, d15N, dO2/N2, dAr/N2, d40/36Ar, d40/38Ar 2021 \u0026 2022; Allan Hills Stable Water Isotopes; CO2 and CH4 from Allan Hills ice cores ALHIC1901, 1902, and 1903; Heavy noble gases (Ar/Xe/Kr) from ALHIC1901, 1902, and 1903; I-165-M GPR Field Report 2019-2020; MOT data (Xe/Kr) from Allan Hills ice cores ALHIC1901, 1902, and 1903; Snapshot record of CO2 and CH4 from the Allan Hills, Antarctica, ranging from 400,000 to 3 million years old", "datasets": [{"dataset_uid": "601897", "doi": "10.15784/601897", "keywords": "Allan Hills; Antarctica; Cryosphere; Glaciology; Ice Core Data; MOT; Ocean Temperature; Paleoclimate; Xe/Kr", "people": "Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "MOT data (Xe/Kr) from Allan Hills ice cores ALHIC1901, 1902, and 1903", "url": "https://www.usap-dc.org/view/dataset/601897"}, {"dataset_uid": "601696", "doi": "10.15784/601696", "keywords": "Allan Hills; Antarctica; Ice Core", "people": "Shackleton, Sarah; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills 2022-23 Shallow Ice Core Field Report", "url": "https://www.usap-dc.org/view/dataset/601696"}, {"dataset_uid": "601669", "doi": "10.15784/601669", "keywords": "Allan Hills; Antarctica; GPR; Ice Core; Report", "people": "Brook, Edward J.; Nesbitt, Ian", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "I-165-M GPR Field Report 2019-2020", "url": "https://www.usap-dc.org/view/dataset/601669"}, {"dataset_uid": "601878", "doi": "10.15784/601878", "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Cryosphere; Methane", "people": "Marks Peterson, Julia; Severinghaus, Jeffrey P.; Shackleton, Sarah; Kalk, Michael; Hishamunda, Valens; Brook, Edward", "repository": "USAP-DC", "science_program": "COLDEX", "title": "Snapshot record of CO2 and CH4 from the Allan Hills, Antarctica, ranging from 400,000 to 3 million years old", "url": "https://www.usap-dc.org/view/dataset/601878"}, {"dataset_uid": "601620", "doi": "10.15784/601620", "keywords": "18O; Allan Hills; Allan Hills Blue Ice; Antarctica; Blue Ice; Delta 15N; Delta 18O; Dole Effect; Firn Thickness; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Chronology; Ice Core Records", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills CMC3 ice core d18Oatm, d15N, dO2/N2, dAr/N2, d40/36Ar, d40/38Ar 2021 \u0026 2022", "url": "https://www.usap-dc.org/view/dataset/601620"}, {"dataset_uid": "609541", "doi": "10.7265/N5NP22DF", "keywords": "Allan Hills; Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Isotope", "people": "Kurbatov, Andrei V.; Introne, Douglas; Mayewski, Paul A.; Spaulding, Nicole", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Allan Hills Stable Water Isotopes", "url": "https://www.usap-dc.org/view/dataset/609541"}, {"dataset_uid": "601895", "doi": "10.15784/601895", "keywords": "Allan Hills; Antarctica; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Noble Gas", "people": "Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Heavy noble gases (Ar/Xe/Kr) from ALHIC1901, 1902, and 1903", "url": "https://www.usap-dc.org/view/dataset/601895"}, {"dataset_uid": "601896", "doi": "10.15784/601896", "keywords": "Allan Hills; Antarctica; Ch4; CO2; Cryosphere; Glaciology; Glaciology; Ice Core Data; Ice Core Records", "people": "Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "CO2 and CH4 from Allan Hills ice cores ALHIC1901, 1902, and 1903", "url": "https://www.usap-dc.org/view/dataset/601896"}], "date_created": "Fri, 27 Aug 2021 00:00:00 GMT", "description": "Bubbles of ancient air trapped in ice cores have been used to directly reconstruct atmospheric composition, and its links to Antarctic and global climate, over the last 800,000 years. Previous field expeditions to the Allan Hills Blue Ice Area, Antarctica, have recovered ice cores that extend as far back as 2.7 million years, by far the oldest polar ice samples yet recovered. These ice cores extend direct observations of atmospheric carbon dioxide and methane concentrations and indirect records of Antarctic climate into a period of Earth\u0027s climate history that represents a plausible geologic analogue to future anthropogenic climate change. The results demonstrate a smaller glacial-interglacial variability of climate and greenhouse gases, and a persistent linkage between Antarctic climate and atmospheric carbon dioxide, between 1 and 2 million years ago. Through this project, the team will return to the Allan Hills Blue Ice Area to recover additional ice cores that date to 2 million years or older. The climate records developed from these ice cores will provide new insights into the chemical composition of the atmosphere and Antarctic climate during times of comparable or even greater warmth than the present day. Project results will help answer questions about issues associated with anthropogenic change including the relationship between temperature change and the mass balance of Antarctic ice and the relationship between atmospheric greenhouse gases and global climate change. Earth has been cooling, and ice sheets expanding, over the past ~52 million years. Superimposed on this cooling are periodic changes in Earth\u0027s climate system driven by variations in the eccentricity, precession, and obliquity of Earth\u0027s orbit around the Sun. Climate reconstructions based on measurements of oxygen isotopes in foraminiferal calcite indicate that, from ~2.8 to 1.2 million years before present (Ma), Earth\u0027s climate system oscillated between glacial and interglacial states every ~40,000 years (the \"40k world\"). Between 1.2-0.8 Ma and continuing to the present, the period of glacial cycles increased in amplitude and lengthened to ~100,000 years (the \"100k world\"). Ice cores preserve ancient air that allows direct reconstructions of atmospheric carbon dioxide and methane. They also archive proxy records of regional climate, mean ocean temperature, global oxygen cycling, and the aridity of nearby continents. Studies of stratigraphically continuous ice cores, extending to 800,000 years before present, have demonstrated that atmospheric carbon dioxide is strongly linked to climate, and it is of great interest to extend the ice-core record into the 40k world. Recent discoveries of well-preserved ice dating from 1.0 to 2.7 Ma from ice cores drilled in the Allan Hills Blue Ice Area (BIA), Antarctica, demonstrate the potential to retrieve stratigraphically discontinuous old ice at shallow depths (\u003c200 meters). This project will continue this work by retrieving new large-volume ice cores and measuring paleoclimate properties in both new and existing ice from the Allan Hills BIA. The experimental objectives are to more fully characterize fundamental properties of the climate system and the carbon cycle during the 40k world. Project results will have implications for Pleistocene climate change, and will provide new constraints on the processes that regulate atmospheric carbon dioxide, methane, and oxygen on geologic timescales. Given a demonstrated age of the ice at the Allan Hills BIA of at least 2 million years, the team will drill additional cores to prospect for ice that predates the initiation of Northern Hemisphere glaciation at the Plio-Pleistocene transition (~2.8 Ma). This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 159.41667, "geometry": "POINT(159.29167 -76.7)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USAP-DC; SNOW/ICE; Allan Hills; FIELD SURVEYS; USA/NSF; Amd/Us; LABORATORY", "locations": "Allan Hills", "north": -76.66667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Mayewski, Paul A.; Kurbatov, Andrei V.; Brook, Edward J.; Severinghaus, Jeffrey P.; Higgins, John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.73333, "title": "Collaborative research: Snapshots of Early and Mid-Pleistocene Climate and Atmospheric Composition from the Allan Hills Blue Ice Area ", "uid": "p0010253", "west": 159.16667}, {"awards": "2114839 Passchier, Sandra", "bounds_geometry": null, "dataset_titles": "Argon thermochronological data on Pliocene ice-rafted detrital mineral grains from IODP Expedition 379 in the Amundsen Sea sector; Grain-size data for the Pliocene section at IODP Site U1533, Amundsen Sea", "datasets": [{"dataset_uid": "601907", "doi": "10.15784/601907", "keywords": "40Ar/39Ar; Amundsen Sea; Amundsen Sea Sector; Antarctica; Cryosphere; Ice-Rafted Detritus; IODP; Paleoclimate; Pliocene; Provenance; Sedimentology", "people": "Hemming, Sidney R.; Passchier, Sandra", "repository": "USAP-DC", "science_program": null, "title": "Argon thermochronological data on Pliocene ice-rafted detrital mineral grains from IODP Expedition 379 in the Amundsen Sea sector", "url": "https://www.usap-dc.org/view/dataset/601907"}, {"dataset_uid": "601900", "doi": "10.15784/601900", "keywords": "Amundsen Sea Sector; Antarctica; Cryosphere; Glaciation; Grain Size; Pliocene; Sediment Core Data; Sedimentology", "people": "Mino-Moreira, Lisbeth; Passchier, Sandra", "repository": "USAP-DC", "science_program": null, "title": "Grain-size data for the Pliocene section at IODP Site U1533, Amundsen Sea", "url": "https://www.usap-dc.org/view/dataset/601900"}], "date_created": "Wed, 25 Aug 2021 00:00:00 GMT", "description": "The West Antarctic Ice Sheet is the most vulnerable polar ice mass to warming and already a major contributor to global mean sea level rise. Its fate in the light of prolonged warming is a topic of major uncertainty. Accelerated sea level rise from ice mass loss in the polar regions is a major concern as a cause of increased coastal flooding affecting millions of people. This project will disclose a unique geological archive buried beneath the seafloor off the Amundsen Sea, Antarctica, which will reveal how the West Antarctic Ice Sheet behaved in a warmer climate in the past. The data and insights can be used to inform ice-sheet and ocean modeling used in coastal policy development. The project will also support the development of a competitive U.S. STEM workforce. Online class exercises for introductory geology classes will provide a gateway for qualified students into undergraduate research programs and this project will enhance the participation of women in science by funding the education of current female Ph.D. students. The project targets the long-term variability of the West Antarctic Ice Sheet over several glacial-interglacial cycles in the early Pliocene sedimentary record drilled by the International Ocean Discovery Program (IODP) Expedition 379 in the Amundsen Sea. Data collection includes 1) the sand provenance of ice-rafted debris and shelf diamictites and its sources within the Amundsen Sea and Antarctic Peninsula region; 2) sedimentary structures and sortable silt calculations from particle size records and reconstructions of current intensities and interactions; and 3) the bulk provenance of continental rise sediments compared to existing data from the Amundsen Sea shelf with investigations into downslope currents as pathways for Antarctic Bottom Water formation. The results are analyzed within a cyclostratigraphic framework of reflectance spectroscopy and colorimetry (RSC) and X-ray fluorescence scanner (XRF) data to gain insight into orbital forcing of the high-latitude processes. The early Pliocene Climatic Optimum (PCO) ~4.5-4.1 Ma spans a major warm period recognized in deep-sea stable isotope and sea-surface temperature records. This period also coincides with a global mean sea level highstand of \u003e 20 m requiring contributions in ice mass loss from Antarctica. The following hypotheses will be tested: 1) that the West Antarctic Ice Sheet retreated from the continental shelf break through an increase in sub iceshelf melt and iceberg calving at the onset of the PCO ~4.5 Ma, and 2) that dense shelf water cascaded down through slope channels after ~4.5 Ma as the continental shelf became exposed during glacial terminations. The project will reveal for the first time how the West Antarctic Ice Sheet operated in a warmer climate state prior to the onset of the current \u201cicehouse\u201d period ~3.3 Ma. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; TERRIGENOUS SEDIMENTS; Amd/Us; SEDIMENTS; FIELD SURVEYS; Amundsen Sea; USAP-DC; AMD", "locations": "Amundsen Sea", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Passchier, Sandra", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "West Antarctic Ice-sheet Change and Paleoceanography in the Amundsen Sea Across the Pliocene Climatic Optimum", "uid": "p0010252", "west": null}, {"awards": "1941304 Sherrell, Robert; 1941483 Yager, Patricia; 1941292 St-Laurent, Pierre; 1941308 Fitzsimmons, Jessica; 1941327 Stammerjohn, Sharon", "bounds_geometry": "POLYGON((-120 -71,-118 -71,-116 -71,-114 -71,-112 -71,-110 -71,-108 -71,-106 -71,-104 -71,-102 -71,-100 -71,-100 -71.4,-100 -71.8,-100 -72.2,-100 -72.6,-100 -73,-100 -73.4,-100 -73.8,-100 -74.2,-100 -74.6,-100 -75,-102 -75,-104 -75,-106 -75,-108 -75,-110 -75,-112 -75,-114 -75,-116 -75,-118 -75,-120 -75,-120 -74.6,-120 -74.2,-120 -73.8,-120 -73.4,-120 -73,-120 -72.6,-120 -72.2,-120 -71.8,-120 -71.4,-120 -71))", "dataset_titles": "Dataset: A numerical simulation of the ocean, sea ice and ice shelves in the Amundsen Sea (Antarctica) over the period 2006-2022 and its associated code and input files; Expedition Data of NBP2202; Numerical experiments examining the response of onshore oceanic heat supply to yearly changes in the Amundsen Sea icescape (Antarctica); Vertical ocean profiles collected by a Conductivity-Temperature-Depth (CTD) package in the Amundsen Sea", "datasets": [{"dataset_uid": "200311", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP2202", "url": "https://www.rvdata.us/search/cruise/NBP2202"}, {"dataset_uid": "200400", "doi": "10.17882/99231", "keywords": null, "people": null, "repository": "SEANOE", "science_program": null, "title": "Numerical experiments examining the response of onshore oceanic heat supply to yearly changes in the Amundsen Sea icescape (Antarctica)", "url": "https://doi.org/10.17882/99231"}, {"dataset_uid": "200399", "doi": "10.25773/bt54-sj65", "keywords": null, "people": null, "repository": "William \u0026 Mary ScholarWorks", "science_program": null, "title": "Dataset: A numerical simulation of the ocean, sea ice and ice shelves in the Amundsen Sea (Antarctica) over the period 2006-2022 and its associated code and input files", "url": "https://doi.org/10.25773/bt54-sj65"}, {"dataset_uid": "601785", "doi": "10.15784/601785", "keywords": "Amundsen Sea; Antarctica; Cryosphere; CTD; NBP2202; Oceanography; R/v Nathaniel B. Palmer", "people": "Stammerjohn, Sharon", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Vertical ocean profiles collected by a Conductivity-Temperature-Depth (CTD) package in the Amundsen Sea", "url": "https://www.usap-dc.org/view/dataset/601785"}], "date_created": "Fri, 20 Aug 2021 00:00:00 GMT", "description": "Part I: Non-technical summary: The Amundsen Sea is adjacent to the West Antarctic Ice Sheet (WAIS) and hosts the most productive coastal ecosystem in all of Antarctica, with vibrant green waters visible from space and an atmospheric carbon dioxide uptake rate ten times higher than the Southern Ocean average. The region is also an area highly impacted by climate change and glacier ice loss. Upwelling of warm deep water is causing melt under the ice sheet, which is contributing to sea level rise and added nutrient inputs to the region. This is a project that is jointly funded by the National Science Foundation\u2019s Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award, each Agency funds the proportion of the budget and the investigators associated with its own country. In this collaboration, the US team will undertake biogeochemical sampling alongside a UK-funded physical oceanographic program to evaluate the contribution of micronutrients such as iron from glacial meltwater to ecosystem productivity and carbon cycling. Measurements will be incorporated into computer simulations to examine ecosystem responses to further glacial melting. Results will help predict future impacts on the region and determine whether the climate sensitivity of the Amundsen Sea ecosystem represents the front line of processes generalizable to the greater Antarctic. This study is aligned with the large International Thwaites Glacier Collaboration (ITGC) and will make data available to the full scientific community. The program will provide training for undergraduate, graduate, post-doctoral, and early-career scientists in both science and communication. The team will also develop out-of-school science experiences for middle and high schoolers related to climate change and Antarctica. Part II: Technical summary: The Amundsen Sea hosts the most productive polynya in all of Antarctica, with atmospheric carbon dioxide uptake rates ten times higher than the Southern Ocean average. The region is vulnerable to climate change, experiencing rapid losses in sea ice, a changing icescape and some of the fastest melting glaciers flowing from the West Antarctic Ice Sheet, a process being studied by the International Thwaites Glacier Collaboration. The biogeochemical composition of the outflow from the glaciers surrounding the Amundsen Sea is largely unstudied. In collaboration with a UK-funded physical oceanographic program, ARTEMIS is using shipboard sampling for trace metals, carbonate system, nutrients, organic matter, and microorganisms, with biogeochemical sensors on autonomous vehicles to gather data needed to understand the impact of the melting ice sheet on both the coastal ecosystem and the regional carbon cycle. These measurements, along with access to the advanced physical oceanographic measurements will allow this team to 1) bridge the gap between biogeochemistry and physics by adding estimates of fluxes and transport of limiting micronutrients; 2) provide biogeochemical context to broaden understanding of the global significance of ocean-ice shelf interactions; 3) determine processes and scales of variability in micronutrient supply that drive the ten-fold increase in carbon dioxide uptake, and 4) identify small-scale processes key to iron and carbon cycling using optimized field sampling. Observations will be integrated into an ocean model to enhance predictive capabilities of regional ocean function. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -100.0, "geometry": "POINT(-110 -73)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; USA/NSF; USAP-DC; AMD; Amundsen Sea; Amd/Us; SHIPS", "locations": "Amundsen Sea", "north": -71.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Yager, Patricia; Medeiros, Patricia; Sherrell, Robert; St-Laurent, Pierre; Fitzsimmons, Jessica; Stammerjohn, Sharon", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "R2R; SEANOE; USAP-DC; William \u0026 Mary ScholarWorks", "science_programs": "Thwaites (ITGC)", "south": -75.0, "title": "NSFGEO-NERC: Collaborative Research: Accelerating Thwaites Ecosystem Impacts for the Southern Ocean (ARTEMIS)", "uid": "p0010249", "west": -120.0}, {"awards": "1947453 Hunt, Kathleen; 1927742 Fleming, Alyson; 1927709 Friedlaender, Ari", "bounds_geometry": "POLYGON((150 -60,153 -60,156 -60,159 -60,162 -60,165 -60,168 -60,171 -60,174 -60,177 -60,180 -60,180 -61.5,180 -63,180 -64.5,180 -66,180 -67.5,180 -69,180 -70.5,180 -72,180 -73.5,180 -75,177 -75,174 -75,171 -75,168 -75,165 -75,162 -75,159 -75,156 -75,153 -75,150 -75,150 -73.5,150 -72,150 -70.5,150 -69,150 -67.5,150 -66,150 -64.5,150 -63,150 -61.5,150 -60))", "dataset_titles": "Bulk stable isotope data of blue and fin whales; Hormone meta data for Antarctic blue and fin whales", "datasets": [{"dataset_uid": "601901", "doi": "10.15784/601901", "keywords": "Antarctica; Biota; Cryosphere; Isotope; Southern Ocean; Whales", "people": "Fleming, Alyson; Smith, Malia", "repository": "USAP-DC", "science_program": null, "title": "Bulk stable isotope data of blue and fin whales", "url": "https://www.usap-dc.org/view/dataset/601901"}, {"dataset_uid": "601908", "doi": "10.15784/601908", "keywords": "Antarctica; Biota; Blue Whale; Cryosphere; Fin Whale; Hormones; Oceans; Reproduction; Whales", "people": "Hunt, Kathleen; Fleming, Alyson", "repository": "USAP-DC", "science_program": null, "title": "Hormone meta data for Antarctic blue and fin whales", "url": "https://www.usap-dc.org/view/dataset/601908"}], "date_created": "Tue, 10 Aug 2021 00:00:00 GMT", "description": "Blue and fin whales are the two largest animals on the planet, and the two largest krill predators in the Southern Ocean. Commercial whaling in Antarctic waters started in the early 1900?s, and by the 1970\u0027s whale populations were reduced from thousands to only a few hundred individuals. The absence of data about whale biology and ecology prior to these large population reductions has limited our understanding of how the ecosystem functioned when cetacean populations were more robust. However, an archive of baleen plates from 800 Antarctic blue and fin whales harvested between 1946 and 1948 was recently rediscovered in the Smithsonian\u0027s National Museum of Natural History that will shed insight into historic whale ecology. As baleen grows, it incorporates circulating hormones, and compounds from the whale\u0027s diet, recording continuous biological and oceanographic information across multiple years. This project will apply a suite of modern molecular techniques to these archived specimens to ask how blue and fin whale foraging and reproduction responded to climate variability, changes at the base of the food web, and whaling activities in the early 1940s. By comparison with more modern datasets, these investigations will fill major gaps in understanding of the largest krill predators, their response to disturbance and environmental change, and the impact that commercial whaling has had on the structure and function of the Antarctic marine ecosystem. This project will improve stem education through annual programming for middle and high school girls in partnership with UNCW\u0027s Marine Quest program. Public outreach will occur through partnerships with the Smithsonian and the International Association of Antarctic Tour Operators to deliver emerging research on Antarctic ecosystems and highlight the contemporary relevance and scientific value of museum collections. Examination of past conditions and adaptations of polar biota is fundamental to predictions of future climate change scenarios. The baleen record that will be used in this study forms an ideal experimental platform for studying bottom-up, top-down and anthropogenic impacts on blue and fin whales. This historic baleen archive includes years with strong climate and temperature anomalies allowing the influence of climate variability on predators and the ecosystems that support them to be examined. Additionally, the impact of commercial whaling on whale stress levels will be investigated by comparing years of intensive whaling with the non-whaling years of WWII, both of which are captured in the time series. There are three main approaches to this project. First, bulk stable isotope analysis will be used to examine the trophic dynamics of Antarctic blue and fin whales. Second, compound-specific stable isotope analyses (CSIA-AA) will characterize the biogeochemistry of the base of the Antarctic food web. Finally, analyses of hormone levels in baleen will reveal differences in stress levels and reproductive status of individuals, and inform understanding of cetacean population biology. This project will generate a new public data archive to foster research opportunities across various components of the OPP program, all free from the logistical constraints of Antarctic field work. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(165 -67.5)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; PELAGIC; MAMMALS; LABORATORY; AMD; Amd/Us; Southern Ocean; USAP-DC; USA/NSF", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fleming, Alyson; Friedlaender, Ari; McCarthy, Matthew; Hunt, Kathleen", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0, "title": "Collaborative Research: A New Baseline for Antarctic Blue and Fin Whales", "uid": "p0010240", "west": 150.0}, {"awards": "1952199 Schneider, David", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Variable-resolution CESM2 over Antarctica (ANTSI): Monthly outputs used for evaluation", "datasets": [{"dataset_uid": "200417", "doi": "10.5281/zenodo.7335891", "keywords": null, "people": null, "repository": "Zenodo", "science_program": null, "title": "Variable-resolution CESM2 over Antarctica (ANTSI): Monthly outputs used for evaluation", "url": "https://zenodo.org/records/7335892"}], "date_created": "Wed, 21 Jul 2021 00:00:00 GMT", "description": "The Antarctic Ice Sheet (AIS) is sensitive to and an indicator of climate change. While ice loss is largely driven by ocean warming, this might be mitigated by enhanced snowfall on the ice sheet. By developing an understanding of the processes governing snowfall variability and change on the AIS, this project will contribute to understanding the long-term role of the AIS as a contributor to sea-level rise. This project is strongly embedded in the collaborative, open-source framework of the Community Earth System Model version 2 (CESM2) and will deliver new datasets of Antarctic precipitation for use by the research community. The project will help to build a diverse geoscience workforce by recruiting and training a student to be directly involved in the research through the Significant Opportunities in Atmospheric Research and Science (SOARS) program. The project will leverage the Climate Model Intercomparison Project 6 climate model ensemble as a whole, and CESM2 in particular, to disentangle the major sources of uncertainty and to elucidate the underlying mechanisms of Antarctic precipitation change, with a particular focus on the role of atmospheric circulation changes relative to the role of atmospheric warming. Using the variable resolution capabilities of CESM2, the team will provide the community with precipitation estimates at a very high horizontal resolution. The analyses will also use a forthcoming 100-member large ensemble. The project seeks to answer the following questions: 1) How well does the CESM2 represent the present-day Antarctic surface climate, precipitation, and surface mass balance, including the mean and its variability? 2) What is the sensitivity of simulated Antarctic precipitation to model resolution in present-day and future climates? 3) What are the roles of thermodynamics (warming atmosphere and ocean) and dynamics (changes in atmospheric circulation) in observed and projected snowfall changes? How do these break down into forced and internal variability? In particular, is there a significant forced precipitation trend due to circulation changes driven by stratospheric ozone depletion and recovery and increases in greenhouse gas concentration? 4) What processes and boundary conditions drive the ensemble spread of Antarctic precipitation in single-model and multi-model ensembles? How does the spread driven by initial surface conditions (including sea ice cover, surface fluxes, inversion strength) compare with the irreducible uncertainty due to internal climate system variability? This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; ICE SHEETS; Amd/Us; Antarctica; AMD; SNOW; MODELS; USAP-DC", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Schneider, David; Datta, Rajashree Tri", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "Zenodo", "repositories": "Zenodo", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Uncertainty and Mechanisms of Antarctica\u2019s Changing Snowfall and its Role in Sea Level Change", "uid": "p0010233", "west": -180.0}, {"awards": "1943550 McDonald, Birgitte", "bounds_geometry": "POLYGON((168 -77,168.3 -77,168.6 -77,168.9 -77,169.2 -77,169.5 -77,169.8 -77,170.1 -77,170.4 -77,170.7 -77,171 -77,171 -77.1,171 -77.2,171 -77.3,171 -77.4,171 -77.5,171 -77.6,171 -77.7,171 -77.8,171 -77.9,171 -78,170.7 -78,170.4 -78,170.1 -78,169.8 -78,169.5 -78,169.2 -78,168.9 -78,168.6 -78,168.3 -78,168 -78,168 -77.9,168 -77.8,168 -77.7,168 -77.6,168 -77.5,168 -77.4,168 -77.3,168 -77.2,168 -77.1,168 -77))", "dataset_titles": "Late chick-rearing foraging ecology of emperor penguins from the Cape Crozier colony; Post-molt emperor penguin foraging ecology", "datasets": [{"dataset_uid": "601686", "doi": "10.15784/601686", "keywords": "Antarctica; Biota; Emperor Penguin; NBP2302; Post-Molt; Ross Sea", "people": "McDonald, Birgitte", "repository": "USAP-DC", "science_program": null, "title": "Post-molt emperor penguin foraging ecology", "url": "https://www.usap-dc.org/view/dataset/601686"}, {"dataset_uid": "601688", "doi": "10.15784/601688", "keywords": "Animal Tracking; Antarctica; Biota; Emperor Penguin; GPS; Late Chick Rearing; Ross Sea", "people": "McDonald, Birgitte", "repository": "USAP-DC", "science_program": null, "title": "Late chick-rearing foraging ecology of emperor penguins from the Cape Crozier colony", "url": "https://www.usap-dc.org/view/dataset/601688"}], "date_created": "Tue, 20 Jul 2021 00:00:00 GMT", "description": "Part I: Non-technical Summary Understanding the mechanisms that animals use to find and acquire food is a fundamental question in ecology. The survival and success of marine predators depends on their ability to locate prey in a variable or changing environment. To do this the predators need to be able to adjust foraging behavior depending on the conditions they encounter. Emperor penguins are ice-dependent, top predators in Antarctica. However, they are vulnerable to environmental changes that alter food web or sea ice coverage, and environmental change may lead to changes in penguin foraging behavior, and ultimately survival and reproduction success. Despite their importance in the Southern Ocean ecosystem, relatively little is known about the specific mechanisms Emperor penguins use to find and acquire food. This study combines a suite of technological and analytical tools to gain essential knowledge on Ross Sea penguin foraging energetics, ecology, and habitat use during critical periods in their life history, especially during late chick-rearing periods. Energy management is particularly crucial during this time as parents need to feed both themselves and their rapidly growing offspring, while being constrained to regions near the colony. Penguin ecology and habitat preference will also be evaluated after the molt and through early reproduction. This study fills important ecological knowledge gaps on the energy balance, diet, and habitat use by penguins during these critical periods. Finally, the project furthers the NSF goals of training new generations of scientists through training of undergraduates, graduate students and a postdoctoral researcher. Public outreach activities will be aligned with another NSF funded project designed to provide science training in afterschool and camp programs that target underrepresented groups. Part II: Technical summary This project will identify behavioral and physiological variability in foraging Emperor penguins that can be directly linked to individual success in the marine environment using an ecological theoretical framework during two critical life history stages. First, this project will investigate the foraging energetics, ecology, and habitat use of Emperor penguins at Cape Crozier using fine-scale movement and video data loggers during the energetically demanding life history phase of late chick-rearing. Specifically, this study will 1) Estimate the relationship of foraging efficiency to foraging behavior and diet using an optimal foraging theory framework to identify what environmental or physiological constraints influence foraging behavior; 2) Investigate the inter- and intra-individual behavioral variability exhibited by emperor penguins, which is essential to predict how resilient these penguins are to environmental change; and 3) Integrate penguin foraging efficiency data with environmental data to identify important habitat. Next the researchers will study the ecology and habitat preference after the molt and through early reproduction using satellite-linked data loggers. The team will: 1) Investigate penguin inter- and intra-individual behavioral variability during the three-month post-molt and early winter foraging trips; and 2) Integrate penguin behavioral data with environmental data to identify which environmental features are indicative of habitat preference when penguins are not constrained to returning to the colony to feed a chick. These fine- and coarse-scale data will be combined with climate predictions to create predictive habitat models. The education objectives of this CAREER project are designed to inspire, engage, and train the next generation of scientists using the data and video generated while investigating Emperor penguins in the Antarctic ecosystem. This includes development of two university courses, training of undergraduate and graduate students, and a collaboration with the NSF funded \u201cPolar Literacy: A model for youth engagement and learning\u201d program to develop after school and camp curriculum that target undeserved and underrepresented groups. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 171.0, "geometry": "POINT(169.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; PENGUINS; MARINE ECOSYSTEMS; USA/NSF; Ross Sea; FIELD SURVEYS; USAP-DC; AMD", "locations": "Ross Sea", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "McDonald, Birgitte", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "CAREER: Foraging Ecology and Physiology of Emperor Penguins in the Ross Sea", "uid": "p0010232", "west": 168.0}, {"awards": "1744794 Jenouvrier, Stephanie; 1744989 LaRue, Michelle", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Detecting climate signals in populations: case of emperor penguin; Emperor penguin population trends (2009-2018); Landfast ice: a major driver of reproductive success in a polar seabird", "datasets": [{"dataset_uid": "200388", "doi": "", "keywords": null, "people": null, "repository": "Github", "science_program": null, "title": "Emperor penguin population trends (2009-2018)", "url": "https://github.com/davidiles/EMPE_Global"}, {"dataset_uid": "601491", "doi": "10.15784/601491", "keywords": "Antarctica", "people": "Jenouvrier, Stephanie", "repository": "USAP-DC", "science_program": null, "title": "Detecting climate signals in populations: case of emperor penguin", "url": "https://www.usap-dc.org/view/dataset/601491"}, {"dataset_uid": "601513", "doi": "10.15784/601513", "keywords": "Antarctica; Breeding Success; Emperor Penguin; Fast Sea Ice", "people": "Jenouvrier, Stephanie; Labrousse, Sara", "repository": "USAP-DC", "science_program": null, "title": "Landfast ice: a major driver of reproductive success in a polar seabird", "url": "https://www.usap-dc.org/view/dataset/601513"}], "date_created": "Wed, 14 Jul 2021 00:00:00 GMT", "description": "The emperor penguin is an iconic seabird that is found in colonies distributed around the entirety of the Antarctic coastline. Emperor penguins are an important indicator species for the health of the Southern Ocean because their reliance on sea ice for major parts of their life cycle means that their population can be influenced by changes in the extent and duration of sea ice around Antarctica. Although baseline data exists on emperor penguin distributions and overall population size, data on how population size varies at individual colonies is limited to only a few locations. Thus, knowledge about how changes in local or regional environmental conditions impacts local or global population status is poorly understood. By combining established methods in satellite remote sensing with ground and aerial surveys of several colonies across the continent, this project will generate population estimates for the 54 known emperor penguin colonies. Decadal scale population trend data will be combined with environmental variables (e.g., sea ice extent and duration among others) to reveal which conditions influence population fluctuations at regional and continental scales. The project will engage with international collaborators, train post-doctoral associates and future scientists, and develop citizen science and K-12 outreach programs. This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; Ross Sea; USAP-DC; AMD; COMMUNITY DYNAMICS; Amd/Us", "locations": "Ross Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Ito, Emi; Jenouvrier, Stephanie", "platforms": null, "repo": "Github", "repositories": "Github; USAP-DC", "science_programs": null, "south": -90.0, "title": "A Multi-scale Approach to Understanding Spatial and Population Variability in Emperor Penguins", "uid": "p0010229", "west": -180.0}, {"awards": "2000992 Romans, Brian", "bounds_geometry": "POINT(-172.873074 -74.274008)", "dataset_titles": "Grain size of Plio-Pleistocene continental slope and rise sediments, Hillary Canyon, Ross Sea", "datasets": [{"dataset_uid": "601807", "doi": "10.15784/601807", "keywords": "Antarctica; Cryosphere; Grain Size; Ross Sea", "people": "Romans, Brian W.; Varela, Natalia", "repository": "USAP-DC", "science_program": null, "title": "Grain size of Plio-Pleistocene continental slope and rise sediments, Hillary Canyon, Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601807"}], "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "Part I: Non-technical description: Predicting how polar ice sheets will respond to future global warming is difficult because all the processes that contribute to their melting are not well understood. This is important because the more ice on land that melts, the higher sea levels will rise. The most significant uncertainty in current estimates of sea-level rise in the coming decades is the potential contribution from the Antarctic Ice Sheet. One way to increase our knowledge about how large ice sheets respond to climate change in response to natural factors is to examine the geologic past. Natural global warming (and cooling) events in Earth\u2019s history provide examples that we can use to better understand processes, interactions, and responses we can\u2019t directly observe today. One such time period, approximately three million years ago (known as the Pliocene), was the last time atmospheric carbon dioxide levels were as high as they are today and, therefore, represents a time period to study to better understand the ice sheet response to a warming climate. Specifically, this project is interested in understanding how ocean currents near Antarctica, which transport heat and store carbon, behaved during these past climate events. The history of past ice sheet-ocean interactions are recorded in sediments that were deposited, layer upon layer, in the deep sea offshore Antarctica. In January-February 2018, a team of scientists and crew set sail to the Ross Sea, offshore west Antarctica, on the scientific ocean drilling vessel JOIDES Resolution to recover such sediment archives. This project focuses on a sediment core from that expedition, which captures the relatively warm Pliocene time interval, as well as the subsequent transition into cooler climates typical of the past two million years. The researchers will analyze the sediment with multiple complementary measurements, including: grain size, composition, chemistry of organic matter, physical structures, microfossil type and abundance, and more. These analyses will be done by the research team, including several students, at their respective laboratories and will then integrated into a unified record of ice sheet-ocean interactions. Ultimately, the results will be used to improve modeled projections of how the Antarctic Ice Sheet could respond to future climate change. Part II: Technical description: Geological records from the Antarctic Ice Sheet (AIS) margin demonstrate that the ice sheet oscillated in response to orbital variations in insolation (i.e., ~400, 100, 41, and 20 kyr), and it appears to be more sensitive to specific frequencies that regulate mean annual insolation (i.e., 41-kyr obliquity), particularly when the ice sheet extends into marine environments and is impacted by ocean circulation. However, the relationship between orbital forcing and the production of Antarctic Bottom Water (AABW) is unconstrained. Thus, a knowledge gap exists in understanding how changing insolation impacts ice marginal and Southern Ocean conditions that directly influence ventilation of the global ocean. The researchers hypothesize that insolation-driven changes directly affected the production and export of AABW to the Southern Ocean from the Pliocene through the Pleistocene. For example, obliquity amplification during the warmer Pliocene may have led to enhanced production and export of dense waters from the shelf due to reduced AIS extent, which, in turn, led to greater AABW outflow. To determine the relationship of AABW production to orbital regime, they plan to reconstruct both from a single, continuous record from the levee of Hillary Canyon, a major conduit of AABW outflow, on the Ross Sea continental rise. To test their hypothesis, they will analyze sediment from IODP Site U1524 (recovered in 2018 during International Ocean Discovery Program Expedition 374) and focus on three data sets. (1) They will use the occurrence, frequency, and character of mm-scale turbidite beds as a proxy of dense-shelf-water cascading outflow and AABW production. They will estimate the down-slope flux via numerical modeling of turbidity current properties using morphology, grain size, and bed thickness as input parameters. (2) They will use grain-size data, physical properties, XRF core scanning, CT imaging, and hyperspectral imaging to guide lithofacies analysis to infer processes occurring during glacial, deglacial, and interglacial periods. Statistical techniques and optimization methods will be applied to test for astronomical forcing of sedimentary packages in order to provide a cyclostratigraphic framework and interpret the orbital-forcing regime. (3) They will use bulk sedimentary carbon and nitrogen abundance and isotope data to determine how relative contributions of terrigenous and marine organic matter change in response to orbital forcing. All of these data will be integrated with sedimentological records to deconvolve organic matter production from its deposition or remobilization due to AABW outflow as a function of the oscillating extent of the AIS. These data sets will be integrated into a unified chronostratigraphy to determine the relationship between AABW outflow and orbital-forcing scenarios under the varying climate regimes of the Plio-Pleistocene. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -172.873074, "geometry": "POINT(-172.873074 -74.274008)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; LABORATORY; AMD; USA/NSF; SEDIMENTS; Amd/Us; Ross Sea", "locations": "Ross Sea", "north": -74.274008, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Patterson, Molly; Ash, Jeanine; Kulhanek, Denise; Ash, Jeannie", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -74.274008, "title": "COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene", "uid": "p0010227", "west": -172.873074}, {"awards": "2001430 Cassano, John", "bounds_geometry": "POLYGON((166 -77,166.4 -77,166.8 -77,167.2 -77,167.6 -77,168 -77,168.4 -77,168.8 -77,169.2 -77,169.6 -77,170 -77,170 -77.1,170 -77.2,170 -77.3,170 -77.4,170 -77.5,170 -77.6,170 -77.7,170 -77.8,170 -77.9,170 -78,169.6 -78,169.2 -78,168.8 -78,168.4 -78,168 -78,167.6 -78,167.2 -78,166.8 -78,166.4 -78,166 -78,166 -77.9,166 -77.8,166 -77.7,166 -77.6,166 -77.5,166 -77.4,166 -77.3,166 -77.2,166 -77.1,166 -77))", "dataset_titles": "Radar Data for Phoenix Airfield (NZFX), 2019", "datasets": [{"dataset_uid": "200358", "doi": "10.48567/wrfx-7c88", "keywords": null, "people": null, "repository": "AMRDC", "science_program": null, "title": "Radar Data for Phoenix Airfield (NZFX), 2019", "url": "https://amrdcdata.ssec.wisc.edu/dataset/radar-data-for-phoenix-airfield-nzfx-2019"}], "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "Despite several decades of successful Antarctic aviation, centered upon flight operations in the McMurdo (Phoenix Field, Ross Island; RsI) area, systemized description of radar observations such as are normally found essential in operational aviation settings are notably lacking. The Ross Island region of Antarctica is a topographically complex region that results in large variations in the mesoscale high wind and precipitation features across the region. The goals of this project are to increase the understanding of the three-dimensional structure of these mesoscale meteorology features. Of particular interest are those features observed with radar signals. This project will leverage observations from the scanning X-band radar installed during the AWARE field campaign in 2016 and the installation of an EWR Radar Systems X-band scanning radar (E700XD) to be deployed during the 2019-20 field season, at McMurdo. Several science questions and case studies will be addressed during the season. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 170.0, "geometry": "POINT(168 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "SNOW; AMD; FIELD SURVEYS; Amd/Us; McMurdo; USAP-DC; USA/NSF; ATMOSPHERIC WINDS", "locations": "McMurdo", "north": -77.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Cassano, John; Seefeldt, Mark; Kingsmill, David", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "AMRDC", "repositories": "AMRDC", "science_programs": null, "south": -78.0, "title": "RAPID: An Improved Understanding of Mesoscale Wind and Precipitation Variability in the Ross Island Region Based on Radar Observations", "uid": "p0010226", "west": 166.0}, {"awards": "1947882 Robel, Alexander", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 01 Jul 2021 00:00:00 GMT", "description": "Uncertainty in projections of future sea level rise comes, in part, from ice-sheet melting under the influence of unpredictable variations in ocean and atmospheric temperature near ice sheets. Using state-of-the-art modeling techniques, the Antarctic Ice Sheet Large Ensemble (AISLENS) Project will estimate the range of possible Antarctic Ice Sheet melt during the recent past and over the next several centuries that could result from such climate variations. The AISLENS Project will also facilitate research by providing modeling output as an open product to the broader climate and glaciology communities. The project will support an early career faculty member, and interdisciplinary training for a graduate student, postdoctoral fellow and undergraduate student. As a part of this project, an undergraduate course on \"Sea Level Rise and Coastal Engineering\" will be also developed, bringing together Earth Science and Civil Engineering students in an interdisciplinary setting and contributing to their education in sea level science and coastal adaptation. This will be done in the geographic context of the Southeastern US, the region of most concentrated vulnerability to sea-level rise in the US. The primary goal of the proposed research is to understand and quantify the role of internal climate variability in driving ice loss from the Antarctic Ice Sheet over the recent past and into the future. The AISLENS Project will encompass hundreds of simulations of Antarctic ice sheet evolution from 1950 to 2300 forced by realistic variations in climate, including snowfall and melt from fluctuating oceanic and atmospheric temperatures. Plausible realizations of Antarctic climate forcing will be generated from stochastic emulation of output from the Energy Exascale Earth System Model (E3SM) under past and future emissions scenarios. These realizations of variable climate will be used to force the MPAS Albany Land Ice (MALI) model, a state-of-the-art model of ice flow in the Antarctic Ice Sheet. In this project, AISLENS will be used to conduct uncertainty and attribution analyses. In the uncertainty analysis, the evolution of ensemble spread in simulations of the future evolution of the Antarctic Ice Sheet will be systematically decomposed to determine which temporal and spatial scales of climate variability contribute the most to future ice-sheet projection uncertainty. In the attribution analysis, a range of satellite-based observations of recent Antarctic ice loss will be compared to the envelope of internal variability of Antarctic ice loss simulated in AISLENS simulations encompassing the recent past. This analysis will provide context to recent observations indicating significant variability of Antarctic climate forcing and provide a possible path forward for conducting robust statistical inference studies for observed ice-sheet changes. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Antarctica; Antarctic Ice Sheet; AMD; USAP-DC; USA/NSF; MODELS; Amd/Us", "locations": "Antarctic Ice Sheet; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Integrated System Science", "paleo_time": null, "persons": "Robel, Alexander", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": null, "title": "The Antarctic Ice Sheet Large Ensemble (AISLENS) Project: Assessing the Role of Climate Variability in Past and Future Ice Sheet Mass Loss", "uid": "p0010223", "west": null}, {"awards": "1933764 Enderlin, Ellyn; 1643455 Enderlin, Ellyn", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Crane Glacier centerline observations and modeling results ; Remotely-sensed iceberg geometries and meltwater fluxes", "datasets": [{"dataset_uid": "601679", "doi": "10.15784/601679", "keywords": "Antarctica; Elevation; Glaciology; Iceberg; Meltwater; Submarine Melt", "people": "Dickson, Adam; Enderlin, Ellyn; Aberle, Rainey; Dryak, Mariama; Miller, Emily; Oliver, Caitlin", "repository": "USAP-DC", "science_program": null, "title": "Remotely-sensed iceberg geometries and meltwater fluxes", "url": "https://www.usap-dc.org/view/dataset/601679"}, {"dataset_uid": "601617", "doi": "10.15784/601617", "keywords": "Antarctica; Antarctic Peninsula; Crane Glacier; Glacier Dynamics; Glacier Mass Discharge; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Modeling; Model Output", "people": "Marshall, Hans-Peter; Meehan, Tate; Kopera, Michal; Aberle, Rainey; Enderlin, Ellyn", "repository": "USAP-DC", "science_program": null, "title": "Crane Glacier centerline observations and modeling results ", "url": "https://www.usap-dc.org/view/dataset/601617"}], "date_created": "Mon, 28 Jun 2021 00:00:00 GMT", "description": "Enderlin/1643455 This award supports a project that will use a novel remote sensing method, which was initially developed to investigate melting of icebergs around Greenland, to examine spatial and temporal variations in ocean forcing around the Antarctic ice sheet periphery. Nearly three-quarters of the Antarctic ice sheet is fringed by regions of floating glacier ice called ice shelves. These ice shelves play an important role in modulating the flow of ice from the ice sheet interior towards the coast, similar to how dams regulate the downstream flow of water from reservoirs. Therefore, a reduction in ice shelf size due to changing air and ocean temperatures can have serious implications for the flux of glacier ice reaching the Antarctic coast, and thus, sea level change. Observations of recent ocean warming in the Amundsen Sea, thinning of the ice shelves, and increased ice flux from the West Antarctic ice sheet interior suggests that ice shelf destabilization triggered by ocean warming may already be underway in some regions. Although detailed observations are available in the Amundsen Sea region, our understanding of spatial and temporal variations in ocean conditions and their influence on ice shelf stability is limited by the scarceness of observations spanning the ice sheet periphery. The project will yield insights into variability in the submarine melting of ice shelves and will help advance the career of a female early-career scientist in a male-dominated field. The project will use repeat, very high-resolution (~0.5 m pixel width and length) satellite images acquired by the WorldView satellites, to estimate rates of iceberg melting in key coastal regions around Antarctica. The satellite images will be used to construct maps of iceberg surface elevation, which will be differenced in time to derive time series of iceberg volume change and area-averaged melt rates. Where ocean data are available, the melt rates will be compared to these data to assess whether variations in ocean temperature can explain observed iceberg melt variability. Large spatial gradients in melt rates will be compared to estimates of iceberg drift rates, which will be inferred from the repeat satellite images as well as numerically modeled drift rates produced by (unfunded) collaborators, to quantify the effects of water shear on iceberg melt rates. Spatial and temporal patterns in iceberg melting will also be compared to independently derived ice shelf thickness datasets. Overall, the analysis should yield insights into the effects of changes in ocean forcing on the submarine melting of Antarctic ice shelves and icebergs. The project does not require field work in Antarctica.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Amery Ice Shelf; FIELD SURVEYS; Totten Glacier; GLACIER MASS BALANCE/ICE SHEET MASS BALANCE; USAP-DC; Antarctic Peninsula; ICEBERGS; Mertz Glacier; OCEAN TEMPERATURE; USA/NSF; Amd/Us; Amundsen Sea; Ronne Ice Shelf; Filchner Ice Shelf; AMD", "locations": "Antarctic Peninsula; Totten Glacier; Ronne Ice Shelf; Filchner Ice Shelf; Amery Ice Shelf; Mertz Glacier; Amundsen Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Enderlin, Ellyn", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Antarctic Submarine Melt Variability from Remote Sensing of Icebergs", "uid": "p0010210", "west": -180.0}, {"awards": "1644159 Jacobs, Stanley", "bounds_geometry": "POLYGON((-180 -72.5,-177 -72.5,-174 -72.5,-171 -72.5,-168 -72.5,-165 -72.5,-162 -72.5,-159 -72.5,-156 -72.5,-153 -72.5,-150 -72.5,-150 -73.15,-150 -73.8,-150 -74.45,-150 -75.1,-150 -75.75,-150 -76.4,-150 -77.05,-150 -77.7,-150 -78.35,-150 -79,-153 -79,-156 -79,-159 -79,-162 -79,-165 -79,-168 -79,-171 -79,-174 -79,-177 -79,180 -79,178.2 -79,176.4 -79,174.6 -79,172.8 -79,171 -79,169.2 -79,167.4 -79,165.6 -79,163.8 -79,162 -79,162 -78.35,162 -77.7,162 -77.05,162 -76.4,162 -75.75,162 -75.1,162 -74.45,162 -73.8,162 -73.15,162 -72.5,163.8 -72.5,165.6 -72.5,167.4 -72.5,169.2 -72.5,171 -72.5,172.8 -72.5,174.6 -72.5,176.4 -72.5,178.2 -72.5,-180 -72.5))", "dataset_titles": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020; Ross Island area salinity and temperature records 1956 to 2020", "datasets": [{"dataset_uid": "601611", "doi": "10.15784/601611", "keywords": "Amundsen Sea; Antarctica; Chemistry:Water; CTD; D18O; NBP0001; NBP0702; NBP0901; NBP1901; NBP2002; Oceans; Oxygen Isotope; R/v Nathaniel B. Palmer; Seawater Isotope; Southern Ocean", "people": "Hennig, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Seawater d18O isotope data from SE Amundsen Sea: 2000, 2007, 2009, 2019, 2020", "url": "https://www.usap-dc.org/view/dataset/601611"}, {"dataset_uid": "601458", "doi": "10.15784/601458", "keywords": "Antarctica; CTD; Oceans; Physical Oceanography; Ross Island; Ross Sea; Salinity; Temperature", "people": "Giulivi, Claudia F.; Jacobs, Stanley", "repository": "USAP-DC", "science_program": null, "title": "Ross Island area salinity and temperature records 1956 to 2020", "url": "https://www.usap-dc.org/view/dataset/601458"}], "date_created": "Fri, 25 Jun 2021 00:00:00 GMT", "description": "Overview and Intellectual merit: This project extends and combines historical and recent ocean data sets to investigate ice-ocean-interactions along the Pacific continental margin of the West Antarctic Ice Sheet. The synthesis focuses on the strikingly different environments on and near the cold Ross Sea and warm Amundsen Sea continental shelves, where available measurements reach back to ~1958 and 1994, respectively. On the more extensively covered Ross Sea continental shelf, multiple reoccupations of ocean stations and transects are used to extend our knowledge of long-term ocean freshening and the mass balance of the world?s largest ice shelf. On the more rugged Amundsen Sea continental shelf, which contains the earth?s fastest melting ice shelves, continuing research on observed thermohaline variability also pursues connections between outer shelf shoals and vulnerable ice shelf grounding zones. This interdisciplinary work updates a prior study of ice shelf response to ocean thermal forcing, and uses chemical tracers to measure changes in shelf, deep and bottom water transformations and production rates. Broader Impacts : Recent and potential future rates of sea level rise are the primary broad-scale impacts of the ice and ocean changes revealed by observations in the study area. The overriding question is whether global and regional sea levels will accelerate gradually, allowing carbon usage reductions to head off the worst consequences, or so rapidly that they will contribute to major social and economic upheavals. Collaborations and data acquired by foreign vessels are also utilized to better understand the causes of rapid change in these shelf seas and ice shelves, along with associated wider implications. Data that are re-gridded, re-edited or newly collated will be archived, and results made available via presentations, publications, and press releases if warranted. This proposal does not require fieldwork in the Antarctic This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -150.0, "geometry": "POINT(-174 -75.75)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; USA/NSF; COMPUTERS; Ross Sea; SHIPS; USAP-DC; SALINITY/DENSITY; OCEAN TEMPERATURE", "locations": "Ross Sea", "north": -72.5, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "West Antarctic Ice Shelf- Ocean Interactions ", "uid": "p0010208", "west": 162.0}, {"awards": "1543286 Walter, Jacob; 1543399 Peng, Zhigang; 1745135 Walter, Jacob", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 19 May 2021 00:00:00 GMT", "description": "The continent of Antarctica has approximately the same surface area as the continental United States, though we know significantly less about its underlying geology and seismic activity. Multinational investments in geophysical infrastructure over the last few decades, especially broadband seismometers operating for several years, are allowing us to observe many interesting natural phenomena, including iceberg calving, ice stream slip, and tectonic earthquakes. To specifically leverage those past investments, we will analyze past and current data to gain a better understanding of Antarctic seismicity. Our recent research revealed that certain large earthquakes occurring elsewhere in the world triggered ice movement near various stations throughout Antarctica. We plan to conduct an exhaustive search of the terabytes of available data, using cutting-edge computational techniques, to uncover additional evidence for ice crevassing, ice stream slip, and earth movement during earthquakes. One specific focus of our research will include investigating whether some of these phenomena may be triggered by external influences, including passing surface waves from distant earthquakes, ocean tides, or seasonal melt. We plan to produce a catalog of the identified activity and share it publicly, so the public and researchers can easily access it. To reach a broader audience, we will present talks to high school classes, including Advanced Placement classes, in the Austin, Texas and Atlanta, Georgia metropolitan areas with emphasis on general aspects of seismic hazard, climate variability, and the geographies of Antarctica. This project will provide research opportunities for undergraduates, training for graduate students, and support for an early-career scientist. In recent years, a new generation of geodetic and seismic instrumentation has been deployed as permanent stations throughout Antarctica (POLENET), in addition to stations deployed for shorter duration (less than 3 years) experiments (e.g. AGAP/TAMSEIS). These efforts are providing critical infrastructure needed to address fundamental questions about both crustal-scale tectonic structures and ice sheets, and their interactions. We plan to conduct a systematic detection of tectonic and icequake activities in Antarctica, focusing primarily on background seismicity, remotely-triggered seismicity, and glacier slip events. Our proposed tasks include: (1) Identification of seismicity throughout the Antarctic continent for both tectonic and ice sources. (2) An exhaustive search for additional triggered events in Antarctica during the last ~15 years of global significant earthquakes. (3) Determination of triggered source mechanisms and whether those triggered events also occur at other times, by analyzing years of data using a matched-filter analysis (where the triggered local event is used to detect similar events). (4) Further analysis of GPS measurements over a ~5.5 year period from Whillans Ice Plain, which suggests that triggering of stick-slip events occurred after the largest earthquakes. An improved knowledge of how the Antarctic ice sheet responds to external perturbations such as dynamic stresses from large distant earthquakes and recent ice unloading could lead to a better understanding of ice failure and related dynamic processes. By leveraging the vast logistical investment to install seismometers in Antarctica over the last decade, our project will build an exhaustive catalog of tectonic earthquakes, icequakes, calving events, and any other detectable near-surface seismic phenomena.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; GLACIERS/ICE SHEETS; USA/NSF; TECTONICS; Amd/Us; AMD; USAP-DC; SEISMOLOGICAL STATIONS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Walter, Jacob; Peng, Zhigang", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Triggering of Antarctic Icequakes, Slip Events, and other Tectonic Phenomena by Distant Earthquakes", "uid": "p0010182", "west": -180.0}, {"awards": "1543377 Seefeldt, Mark; 1543325 Landolt, Scott", "bounds_geometry": "POLYGON((166.918 -77.8675,167.2997 -77.8675,167.6814 -77.8675,168.0631 -77.8675,168.4448 -77.8675,168.8265 -77.8675,169.2082 -77.8675,169.5899 -77.8675,169.9716 -77.8675,170.3533 -77.8675,170.735 -77.8675,170.735 -77.98145,170.735 -78.0954,170.735 -78.20935,170.735 -78.3233,170.735 -78.43725,170.735 -78.5512,170.735 -78.66515,170.735 -78.7791,170.735 -78.89305,170.735 -79.007,170.3533 -79.007,169.9716 -79.007,169.5899 -79.007,169.2082 -79.007,168.8265 -79.007,168.4448 -79.007,168.0631 -79.007,167.6814 -79.007,167.2997 -79.007,166.918 -79.007,166.918 -78.89305,166.918 -78.7791,166.918 -78.66515,166.918 -78.5512,166.918 -78.43725,166.918 -78.3233,166.918 -78.20935,166.918 -78.0954,166.918 -77.98145,166.918 -77.8675))", "dataset_titles": "Precipitation Observations for the Northwest Ross Ice Shelf - 2017-12 to 2019-11", "datasets": [{"dataset_uid": "601441", "doi": "10.15784/601441", "keywords": "Accumulation; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Meteorology; Precipitation; Ross Ice Shelf; Snow; Snow/ice; Snow/Ice; Weatherstation; Weather Station Data", "people": "Seefeldt, Mark", "repository": "USAP-DC", "science_program": null, "title": "Precipitation Observations for the Northwest Ross Ice Shelf - 2017-12 to 2019-11", "url": "https://www.usap-dc.org/view/dataset/601441"}], "date_created": "Tue, 27 Apr 2021 00:00:00 GMT", "description": "Accurately measuring precipitation in Antarctica is important for purposes such as calculating Antarctica?s mass balance and contribution to global sea level rise, interpreting ice core records, and validating model- and satellite-based precipitation estimates. There is a critical need for reliable, autonomous, long-term measurements of Antarctic precipitation in order to better understand its variability in space in time. Such records over time are essentially absent from the continent, despite their importance. This project will deploy and test instrumentation to measure and record rates of snowfall and blowing snow in Antarctica. Project goals are based on installation of four low-power, autonomous Antarctic precipitation systems (APS) co-located at automatic weather station (AWS) sites in the Ross Island region of Antarctica. The APSs are designed with an integrated sensor approach to provide multiple types of observations of snow accumulation types at the test sites. The APSs are designed to construct an accurate timeline of snow accumulation, and to distinguish the water equivalent of fallen precipitation from surface blowing (lofted) snow, a prime confounding factor. The standard suite of instruments to be deployed includes: precipitation gauge with double Alter windshield, laser disdrometer, laser snow height sensor, optical precipitation detector, anemometer at gauge height, and a visible /infrared webcam. These instruments have previously been shown to work well in cold regions applications.", "east": 170.735, "geometry": "POINT(168.8265 -78.43725)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; Amd/Us; USA/NSF; SNOW; Wind Data; WEATHER STATIONS; Ross Ice Shelf", "locations": "Ross Ice Shelf", "north": -77.8675, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Seefeldt, Mark; Landolt, Scott", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e WEATHER STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.007, "title": "Collaborative Research: Implementing Low-power, Autonomous Observing Systems to Improve the Measurement and Understanding of Antarctic Precipitation", "uid": "p0010173", "west": 166.918}, {"awards": "1246151 Bromirski, Peter; 1246416 Stephen, Ralph", "bounds_geometry": "POLYGON((-180 -77,-179.5 -77,-179 -77,-178.5 -77,-178 -77,-177.5 -77,-177 -77,-176.5 -77,-176 -77,-175.5 -77,-175 -77,-175 -77.4,-175 -77.8,-175 -78.2,-175 -78.6,-175 -79,-175 -79.4,-175 -79.8,-175 -80.2,-175 -80.6,-175 -81,-175.5 -81,-176 -81,-176.5 -81,-177 -81,-177.5 -81,-178 -81,-178.5 -81,-179 -81,-179.5 -81,180 -81,179 -81,178 -81,177 -81,176 -81,175 -81,174 -81,173 -81,172 -81,171 -81,170 -81,170 -80.6,170 -80.2,170 -79.8,170 -79.4,170 -79,170 -78.6,170 -78.2,170 -77.8,170 -77.4,170 -77,171 -77,172 -77,173 -77,174 -77,175 -77,176 -77,177 -77,178 -77,179 -77,-180 -77))", "dataset_titles": "Collaborative Research: Dynamic Response of the Ross Ice Shelf to Wave-Induced Vibrations and Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf. International Federation of Digital Seismograph Networks. ; Dynamic Response of the Ross Ice Shelf to Wave-induced Vibrations 2015/2016, UNAVCO, Inc., GPS/GNSS Observations Dataset", "datasets": [{"dataset_uid": "200209", "doi": "10.7283/58E3-GA46", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Dynamic Response of the Ross Ice Shelf to Wave-induced Vibrations 2015/2016, UNAVCO, Inc., GPS/GNSS Observations Dataset", "url": "https://doi.org/10.7283/58E3-GA46"}, {"dataset_uid": "200207", "doi": "10.7914/SN/XH_2014", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Collaborative Research: Dynamic Response of the Ross Ice Shelf to Wave-Induced Vibrations and Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf. International Federation of Digital Seismograph Networks. ", "url": "http://www.fdsn.org/networks/detail/XH_2014/"}], "date_created": "Thu, 15 Apr 2021 00:00:00 GMT", "description": "Bromirski/1246151 This award supports a project intended to discover, through field observations and numerical simulations, how ocean wave-induced vibrations on ice shelves in general, and the Ross Ice Shelf (RIS), in particular, can be used (1) to infer spatial and temporal variability of ice shelf mechanical properties, (2) to infer bulk elastic properties from signal propagation characteristics, and (3) to determine whether the RIS response to infragravity (IG) wave forcing observed distant from the front propagates as stress waves from the front or is \"locally\" generated by IG wave energy penetrating the RIS cavity. The intellectual merit of the work is that ocean gravity waves are dynamic elements of the global ocean environment, affected by ocean warming and changes in ocean and atmospheric circulation patterns. Their evolution may thus drive changes in ice-shelf stability by both mechanical interactions, and potentially increased basal melting, which in turn feed back on sea level rise. Gravity wave-induced signal propagation across ice shelves depends on ice shelf and sub-shelf water cavity geometry (e.g. structure, thickness, crevasse density and orientation), as well as ice shelf physical properties. Emphasis will be placed on observation and modeling of the RIS response to IG wave forcing at periods from 75 to 300 s. Because IG waves are not appreciably damped by sea ice, seasonal monitoring will give insights into the year-round RIS response to this oceanographic forcing. The 3-year project will involve a 24-month period of continuous data collection spanning two annual cycles on the RIS. RIS ice-front array coverage overlaps with a synergistic Ross Sea Mantle Structure (RSMS) study, giving an expanded array beneficial for IG wave localization. The ice-shelf deployment will consist of sixteen stations equipped with broadband seismometers and barometers. Three seismic stations near the RIS front will provide reference response/forcing functions, and measure the variability of the response across the front. A linear seismic array orthogonal to the front will consist of three stations in-line with three RSMS stations. Passive seismic array monitoring will be used to determine the spatial and temporal distribution of ocean wave-induced signal sources along the front of the RIS and estimate ice shelf structure, with the high-density array used to monitor and localize fracture (icequake) activity. The broader impacts include providing baseline measurements to enable detection of ice-shelf changes over coming decades which will help scientists and policy-makers respond to the socio-environmental challenges of climate change and sea-level rise. A postdoctoral scholar in interdisciplinary Earth science will be involved throughout the course of the research. Students at Cuyamaca Community College, San Diego County, will develop and manage a web site for the project to be used as a teaching tool for earth science and oceanography classes, with development of an associated web site on waves for middle school students.", "east": 170.0, "geometry": "POINT(177.5 -79)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; GLACIER MOTION/ICE SHEET MOTION; USAP-DC; Amd/Us; AMD; USA/NSF; Iris; Ross Ice Shelf", "locations": "Ross Ice Shelf", "north": -77.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bromirski, Peter; Gerstoft, Peter; Stephen, Ralph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "UNAVCO", "repositories": "IRIS; UNAVCO", "science_programs": null, "south": -81.0, "title": "Collaborative Research: Dynamic Response of the Ross Ice Shelf to Wave-induced Vibrations", "uid": "p0010169", "west": -175.0}, {"awards": "2002346 Tinto, Kirsteen; 2001714 Muto, Atsuhiro", "bounds_geometry": "POLYGON((-115 -70,-113 -70,-111 -70,-109 -70,-107 -70,-105 -70,-103 -70,-101 -70,-99 -70,-97 -70,-95 -70,-95 -70.8,-95 -71.6,-95 -72.4,-95 -73.2,-95 -74,-95 -74.8,-95 -75.6,-95 -76.4,-95 -77.2,-95 -78,-97 -78,-99 -78,-101 -78,-103 -78,-105 -78,-107 -78,-109 -78,-111 -78,-113 -78,-115 -78,-115 -77.2,-115 -76.4,-115 -75.6,-115 -74.8,-115 -74,-115 -73.2,-115 -72.4,-115 -71.6,-115 -70.8,-115 -70))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 02 Mar 2021 00:00:00 GMT", "description": "Predictions of future changes of the Antarctic ice sheet are essential for understanding changes in the global sea level expected for the coming centuries. These predictions rely on models of ice-sheet flow that in turn rely on knowledge of the physical conditions of the Antarctic continent beneath the ice. Exploration of Antarctica by land, sea, and air has advanced our understanding of the geological material under the Antarctic ice sheet, but this information has not yet been fully integrated into ice-sheet models. This project will take advantage of existing data from decades of US and international investment in geophysical surveys to create a new understanding of the geology underlying the Amundsen Sea and the adjacent areas of the West Antarctic Ice Sheet\u2014a portion of Antarctica that is considered particularly vulnerable to collapse. A series of new datasets called \u201cBed Classes\u201d will be developed that will translate the geological properties of the Antarctic continent in ways that can be incorporated into ice-sheet models. This project will develop a new regional geologic/tectonic framework for the Amundsen Sea Embayment and its ice catchments using extensive marine and airborne geophysical data together with ground-based onshore geophysical and geological constraints to delineate sedimentary basins, bedrock ridges, faults, and volcanic structures. Using this new geologic interpretation of the region, several key issues regarding the geologic influence on ice-sheet stability will be addressed: whether the regional heat flow is dominated by localization along the faults or lithology; the role of geology on the sources, sinks, and flow-paths of subglacial water; the distribution of sediments that determine bed-character variability; and the extent of geologic control on the current Thwaites Glacier grounding line. The impact of improved geological knowledge on ice-sheet models will be tested with the development of a set of \u201cBed Class\u201d grids to capture these new insights for use in the models. Bed Classes will be tested within the Parallel Ice Sheet Model framework with initial experiments to identify the sensitivity of model simulations to geological parameterizations. Through a series of workshops with ice-sheet modelers, the Bed Classes will be refined and made accessible to the broader modelling community. This work aims to ensure that the Bed-Class concept can be applied more broadly to ice-sheet models working in different geographic areas and on different timescales. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -95.0, "geometry": "POINT(-105 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Amundsen Sea; COMPUTERS; GRAVITY ANOMALIES; Amd/Us; GLACIERS/ICE SHEETS; AMD; USA/NSF; USAP-DC", "locations": "Amundsen Sea", "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tinto, Kirsty; Bell, Robin; Porter, David; Muto, Atsu", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS", "repositories": null, "science_programs": null, "south": -78.0, "title": "Collaborative Research: Building Geologically Informed Bed Classes to Improve Projections of Ice Sheet Change", "uid": "p0010164", "west": -115.0}, {"awards": "1929991 Pettit, Erin C; 1738992 Pettit, Erin C", "bounds_geometry": "POLYGON((-114 -74,-113 -74,-112 -74,-111 -74,-110 -74,-109 -74,-108 -74,-107 -74,-106 -74,-105 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105 -76,-106 -76,-107 -76,-108 -76,-109 -76,-110 -76,-111 -76,-112 -76,-113 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))", "dataset_titles": "AMIGOS-IIIa \"Cavity\" Aquadopp current data Jan 2020 - Mar 2021; AMIGOS-IIIa \"Cavity\" Seabird CTD data Jan 2020 - Dec 2021; AMIGOS-III Cavity and Channel Snow Height and Thermistor Snow Temperature Data; AMIGOS-IIIc \"Channel\" Aquadopp current data Jan 2020 - Mar 2021; AMIGOS-IIIc \"Channel\" Seabird CTD data Jan 2020 - Dec 2021; CTD data from the NBP 19/02 cruise as part of the TARSAN project in the Amundsen Sea during austral summer 2018/2019; Dotson-Crosson Ice Shelf data from a tale of two ice shelves paper; Pinning-point shear-zone fractures in Thwaites Eastern Ice Shelf (2002 - 2022); Sentinel-1-derived monthly-averaged velocity components from Thwaites Eastern Ice Shelf, 2016 - 2022; SIIOS Temporary Deployment; Sub-ice-shelf seafloor elevation derived from point-source active-seismic data on Thwaites Eastern Ice Shelf and Dotson Ice Shelf, December 2019 and January 2020; Thwaites Glacier grounding lines for 2014 and 2019/20 from height above flotation; Two-year velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2001-2020; Visala WXT520 weather station data at the Cavity and Channel AMIGOS-III sites; Yearly velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2013-2022", "datasets": [{"dataset_uid": "601547", "doi": "10.15784/601547", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIa \"Cavity\" Aquadopp current data Jan 2020 - Mar 2021", "url": "https://www.usap-dc.org/view/dataset/601547"}, {"dataset_uid": "601545", "doi": "10.15784/601545", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Salinity; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIc \"Channel\" Seabird CTD data Jan 2020 - Dec 2021", "url": "https://www.usap-dc.org/view/dataset/601545"}, {"dataset_uid": "601903", "doi": "10.15784/601903", "keywords": "Antarctica; Cryosphere; Fractures; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Thwaites", "people": "Alley, Karen; Muto, Atsuhiro; Scambos, Ted; Pettit, Erin; Wild, Christian; Luckman, Adrian; Truffer, Martin; Lilien, David; Banerjee, Debangshu", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Pinning-point shear-zone fractures in Thwaites Eastern Ice Shelf (2002 - 2022)", "url": "https://www.usap-dc.org/view/dataset/601903"}, {"dataset_uid": "601827", "doi": "10.15784/601827", "keywords": "Antarctica; Cryosphere; Dotson Ice Shelf; Thwaites Glacier", "people": "Muto, Atsuhiro; Scambos, Ted; Wild, Christian; Pomraning, Dale; Alley, Karen; Roccaro, Alexander; Pettit, Erin; Truffer, Martin; Wallin, Bruce", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Sub-ice-shelf seafloor elevation derived from point-source active-seismic data on Thwaites Eastern Ice Shelf and Dotson Ice Shelf, December 2019 and January 2020", "url": "https://www.usap-dc.org/view/dataset/601827"}, {"dataset_uid": "601914", "doi": null, "keywords": "Antarctica; Cryosphere; Glaciology; Ice Shelf; Thwaites Glacier; Velocity", "people": "Lilien, David; Pettit, Erin; Truffer, Martin; Scambos, Ted; Muto, Atsuhiro; Alley, Karen; Wild, Christian; Banerjee, Debangshu; Luckman, Adrian", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Sentinel-1-derived monthly-averaged velocity components from Thwaites Eastern Ice Shelf, 2016 - 2022", "url": "https://www.usap-dc.org/view/dataset/601914"}, {"dataset_uid": "601552", "doi": "10.15784/601552", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Pine Island Bay; Snow Accumulation; Snow Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-III Cavity and Channel Snow Height and Thermistor Snow Temperature Data", "url": "https://www.usap-dc.org/view/dataset/601552"}, {"dataset_uid": "601544", "doi": "10.15784/601544", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Salinity; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIa \"Cavity\" Seabird CTD data Jan 2020 - Dec 2021", "url": "https://www.usap-dc.org/view/dataset/601544"}, {"dataset_uid": "200204", "doi": "https://doi.org/10.7914/SN/1L_2019", "keywords": null, "people": null, "repository": "International Federation of Digital Seismograph Networks", "science_program": null, "title": "SIIOS Temporary Deployment", "url": "http://www.fdsn.org/networks/detail/1L_2019/"}, {"dataset_uid": "601499", "doi": "10.15784/601499", "keywords": "Amundsen Sea; Antarctica; Glaciology; Grounding Line; Ice Shelf; Thwaites Glacier", "people": "Wild, Christian; Scambos, Ted; Truffer, Martin; Alley, Karen; Muto, Atsu; Pettit, Erin", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Thwaites Glacier grounding lines for 2014 and 2019/20 from height above flotation", "url": "https://www.usap-dc.org/view/dataset/601499"}, {"dataset_uid": "601478", "doi": "10.15784/601478", "keywords": "Antarctica; Glaciology; Ice Shelf; Ice Velocity; Strain Rate; Thwaites Glacier", "people": "Alley, Karen; Truffer, Martin; Klinger, Marin; Pettit, Erin; Muto, Atsu; Scambos, Ted; Wild, Christian; Wallin, Bruce", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Two-year velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2001-2020", "url": "https://www.usap-dc.org/view/dataset/601478"}, {"dataset_uid": "601904", "doi": "10.15784/601904", "keywords": "Antarctica; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Glaciology; Ice Shelf; Remote Sensing; Satellite Imagery; Thwaites; Thwaites Glacier; Velocity", "people": "Luckman, Adrian; Banerjee, Debangshu; Scambos, Ted; Truffer, Martin; Muto, Atsuhiro; Alley, Karen; Wild, Christian; Lilien, David; Pettit, Erin", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Yearly velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2013-2022", "url": "https://www.usap-dc.org/view/dataset/601904"}, {"dataset_uid": "601578", "doi": "10.15784/601578", "keywords": "Antarctica; Dotson Ice Shelf; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology", "people": "Segabinazzi-Dotto, Tiago; Wild, Christian", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Dotson-Crosson Ice Shelf data from a tale of two ice shelves paper", "url": "https://www.usap-dc.org/view/dataset/601578"}, {"dataset_uid": "601549", "doi": "10.15784/601549", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Pine Island Bay; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "Visala WXT520 weather station data at the Cavity and Channel AMIGOS-III sites", "url": "https://www.usap-dc.org/view/dataset/601549"}, {"dataset_uid": "601548", "doi": "10.15784/601548", "keywords": "Amundsen Sea; Antarctica; Ice Shelf; Mooring; Pine Island Bay; Pressure; Temperature; Thwaites Glacier", "people": "Scambos, Ted", "repository": "USAP-DC", "science_program": "Thwaites (ITGC)", "title": "AMIGOS-IIIc \"Channel\" Aquadopp current data Jan 2020 - Mar 2021", "url": "https://www.usap-dc.org/view/dataset/601548"}, {"dataset_uid": "200321", "doi": "10.5285/e338af5d-8622-05de-e053-6c86abc06489", "keywords": null, "people": null, "repository": "British Oceanographic Data Centre", "science_program": null, "title": "CTD data from the NBP 19/02 cruise as part of the TARSAN project in the Amundsen Sea during austral summer 2018/2019", "url": "https://www.bodc.ac.uk/data/published_data_library/catalogue/10.5285/e338af5d-8622-05de-e053-6c86abc06489/"}], "date_created": "Mon, 22 Feb 2021 00:00:00 GMT", "description": "This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Thwaites and neighboring glaciers in the Amundsen Sea Embayment are rapidly losing mass in response to recent climate warming and related changes in ocean circulation. Mass loss from the Amundsen Sea Embayment could lead to the eventual collapse of the West Antarctic Ice Sheet, raising the global sea level by up to 2.5 meters (8 feet) in as short as 500 years. The processes driving the loss appear to be warmer ocean circulation and changes in the width and flow speed of the glacier, but a better understanding of these changes is needed to refine predictions of how the glacier will evolve. One highly sensitive process is the transitional flow of glacier ice from land onto the ocean to become a floating ice shelf. This flow of ice from grounded to floating is affected by changes in air temperature and snowfall at the surface; the speed and thickness of ice feeding it from upstream; and the ocean temperature, salinity, bathymetry, and currents that the ice flows into. The project team will gather new measurements of each of these local environmental conditions so that it can better predict how future changes in air, ocean, or the ice will affect the loss of ice to the ocean in this region. Current and anticipated near-future mass loss from Thwaites Glacier and nearby Amundsen Sea Embayment region is mainly attributed to reduction in ice-shelf buttressing due to sub-ice-shelf melting by intrusion of relatively warm Circumpolar Deep Water into sub-ice-shelf cavities. Such predictions for mass loss, however, still lack understanding of the dominant processes at and near grounding zones, especially their spatial and temporal variability, as well as atmospheric and oceanic drivers of these processes. This project aims to constrain and compare these processes for the Thwaites and the Dotson Ice Shelves, which are connected through upstream ice dynamics, but influenced by different submarine troughs. The team\u0027s specific objectives are to: 1) install atmosphere-ice-ocean multi-sensor remote autonomous stations on the ice shelves for two years to provide sub-daily continuous observations of concurrent oceanic, glaciologic, and atmospheric conditions; 2) measure ocean properties on the continental shelf adjacent to ice-shelf fronts (using seal tagging, glider-based and ship-based surveys, and existing moored and conductivity-temperature-depth-cast data), 3) measure ocean properties into sub-ice-shelf cavities (using autonomous underwater vehicles) to detail ocean transports and heat fluxes; and 4) constrain current ice-shelf and sub-ice-shelf cavity geometry, ice flow, and firn properties for the ice-shelves (using radar, active-source seismic, and gravimetric methods) to better understand the impact of ocean and atmosphere on the ice-sheet change. The team will also engage the public and bring awareness to this rapidly changing component of the cryosphere through a \"Live from the Ice\" social media campaign in which the public can follow the action and data collection from the perspective of tagged seals and autonomous stations. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -104.0, "geometry": "POINT(-109 -75)", "instruments": null, "is_usap_dc": true, "keywords": "Thwaites Glacier; FIELD SURVEYS; GLACIERS/ICE SHEETS", "locations": "Thwaites Glacier", "north": -74.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Glaciology; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Truffer, Martin; Scambos, Ted; Muto, Atsu; Heywood, Karen; Boehme, Lars; Hall, Robert; Wahlin, Anna; Lenaerts, Jan; Pettit, Erin", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "British Oceanographic Data Centre; International Federation of Digital Seismograph Networks; USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment", "uid": "p0010162", "west": -114.0}, {"awards": "1643301 Gerbi, Christopher; 1643353 Christianson, Knut", "bounds_geometry": null, "dataset_titles": "ImpDAR: an impulse radar processor; SeidarT; South Pole Lake ApRES Radar; South Pole Lake GNSS; South Pole Lake: ground-based ice-penetrating radar", "datasets": [{"dataset_uid": "200244", "doi": " https://zenodo.org/badge/latestdoi/382590632", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "SeidarT", "url": "https://github.com/UMainedynamics/SeidarT"}, {"dataset_uid": "200202", "doi": "http://doi.org/10.5281/zenodo.3833057", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "ImpDAR: an impulse radar processor", "url": "https://www.github.com/dlilien/ImpDAR"}, {"dataset_uid": "601503", "doi": "10.15784/601503", "keywords": "Antarctica; Apres; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; South Pole; Subglacial Lakes; Vertical Velocity", "people": "Hills, Benjamin", "repository": "USAP-DC", "science_program": null, "title": "South Pole Lake ApRES Radar", "url": "https://www.usap-dc.org/view/dataset/601503"}, {"dataset_uid": "200203", "doi": "", "keywords": null, "people": null, "repository": "Uni. Washington ResearchWorks Archive", "science_program": null, "title": "South Pole Lake: ground-based ice-penetrating radar", "url": "http://hdl.handle.net/1773/45293"}, {"dataset_uid": "601502", "doi": "10.15784/601502", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GNSS; GPS; GPS Data; South Pole; Subglacial Lakes", "people": "Hills, Benjamin", "repository": "USAP-DC", "science_program": null, "title": "South Pole Lake GNSS", "url": "https://www.usap-dc.org/view/dataset/601502"}], "date_created": "Wed, 17 Feb 2021 00:00:00 GMT", "description": "Gerbi/1643301 This award supports a project to develop software that will allow researchers considering seismic or radar field surveys to test, ahead of time, whether the data they plan to collect will have sufficient resolution to measure the natural variations in the mechanical properties of ice, which determine the response of flowing ice to changing climatic conditions. The mechanical properties of ice depend largely on the temperature and the orientation of the crystals that make up the ice. The most accurate method for measuring ice crystal orientation and temperature is through drilling and direct analysis of an ice core. However, this method is very costly, time-consuming, and limited in spatial coverage. Geophysical techniques, such as seismic and radar, can cover much more area, but we have little knowledge about the practical limitations of these techniques as they relate to calculating mechanical properties. This project addresses that knowledge gap through construction of a computational toolbox that will allow accurate assessment of the ability of geophysical surveys to image crystal orientation and ice temperature. Researchers can then use these tools to adjust the field survey plans to maximize the return on investment. By working to improve the efficiency and effectiveness of future geophysical work related to glacial flow, this proposal will improve scientists? ability to quantify sea-level variations within the larger context of climate change. The project includes building new user-friendly, publicly accessible software and instructional modules. The work will provide training for graduate and undergraduate students, who will play a role in research and develop instructional materials. Ice viscosity, the resistance of ice to flow, exerts significant control over ice velocity. Therefore, mapping ice viscosity is important for understanding the current and future behavior of glaciers and ice sheets. To do so, scientists must determine the temperature and crystal orientation fabric throughout the ice. Seismic and radar techniques can survey large areas quickly, and thus are promising, yet not fully tested, methods to efficiently measure the thermal and mechanical structure of flowing ice. As part of this project, scientists will develop and use a computational framework to quantify the degree to which seismic and radar techniques can resolve the crystal orientation fabric and temperature of streaming ice, and then test how sensitive ice flow is to the attendant uncertainty. To meet these goals, a numerical toolbox will be built which will allow the glacier/ice stream geometry and physical properties (temperature, crystal orientation fabric, density and acidity) to be varied. The toolbox will be capable of both creating synthetic radar and seismic profiles through forward modeling and inverting synthetic profiles to allow evaluation of how well geophysical techniques can image the original thermal and mechanical structure. These simulated radar and seismic data will allow scientists to better quantify the influence of the variability in mechanical properties of the ice on flow velocities and patterns. The results of this work will guide planning for future field campaigns, making them more effective and efficient. This project does not require fieldwork in the Antarctic.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; GLACIERS/ICE SHEETS; USAP-DC; GLACIER MOTION/ICE SHEET MOTION; GLACIER THICKNESS/ICE SHEET THICKNESS; ICE SHEETS; South Pole; USA/NSF; AMD; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; FIELD SURVEYS; Amd/Us", "locations": "South Pole; United States Of America", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Christianson, Knut; Gerbi, Christopher; Campbell, Seth; Vel, Senthil", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "GitHub", "repositories": "GitHub; Uni. Washington ResearchWorks Archive; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow", "uid": "p0010160", "west": null}, {"awards": "1443448 Schaefer, Joerg; 1443144 Steig, Eric", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Simulations of 10Be over Antarctica; South Pole ice Core 10Be CE", "datasets": [{"dataset_uid": "601535", "doi": "10.15784/601535", "keywords": "Antarctica; South Pole", "people": "Schaefer, Joerg", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice Core 10Be CE", "url": "https://www.usap-dc.org/view/dataset/601535"}, {"dataset_uid": "601431", "doi": "10.15784/601431", "keywords": "Antarctica; South Pole", "people": "Schaefer, Joerg; Ding, Qinghua; Steig, Eric J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Simulations of 10Be over Antarctica", "url": "https://www.usap-dc.org/view/dataset/601431"}], "date_created": "Thu, 04 Feb 2021 00:00:00 GMT", "description": "This project will acquire measurements of the concentration of beryllium-10 (10Be) from an ice core from the South Pole, Antarctica. An isotope of the element beryllium, 10Be, is produced in the atmosphere by high-energy protons (cosmic rays) that enter Earth\u0027s atmosphere from space. It is removed from the atmosphere by settling or by scavenging by rain or snowfall. Hence, concentrations of 10Be in snow at the South Pole reflect the production rate of 10Be in the atmosphere. Because the rate of production of 10Be over Antarctica depends primarily on the strength of the Sun\u0027s magnetic field, measurements of 10Be in the South Pole ice core will provide a record of changes in solar activity. The South Pole ice core will reach an age of 40,000 years at the bottom. The project will result in measurements of 10Be at annual resolution for the last 100 years and selected periods in the more distant past, such as the Maunder Minimum, a period during the late 17th century during which no sunspots were observed, or the last glacial cold period, about 20,000 years ago. A climate model that can simulate the production of 10Be in the atmosphere, it\u0027s transport through the atmosphere, and its deposition at the snow surface in Antarctica will be used to aid in using the 10Be data to determine past changes in solar activity from decadal to millennial scale, and in turn to evaluate the role of the Sun in Earth?s climate from a new perspective. The production of 10Be in Earth\u0027s atmosphere results from the spallation of oxygen and nitrogen in the atmosphere by cosmic rays. Cosmic ray variations in the high latitudes are primarily modulated by solar variability. Time-series records of 10Be from ice cores are therefore important for deriving variations in solar activity through time, which is fundamental to understanding climate variability. Deposition of 10Be to the ice surface is also influenced by variability in atmospheric circulation and deposition processes, and South Pole is the best available location for minimizing the influence of variable atmospheric circulation on 10Be deposition. To date, only one record of 10Be exists from South Pole; that record is widely used in solar forcing estimates used in climate models, but covers only the last millennium and ends in CE 1982. We will obtain 10Be concentration measurements in a 1500-m, 40000-year long ice core from the South Pole. This will extend the existing record both further back in time and forward to the present, providing overlap with the modern instrumental record of solar and climate variability. High resolution (annual to biannual) measurements will be made in targeted areas of interest, including the last 100 years, the Maunder Minimum (CE 1650-1715), and the last glacial maximum. The novel data will be used in conjunction with climate model experiments that incorporate 10Be production, transport, and deposition physics. Together, data and modeling will create an updated record of atmospheric 10Be production and hence of solar activity.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "COSMIC RAYS; LABORATORY; BERYLLIUM-10 ANALYSIS; SNOW/ICE; South Pole; GLACIERS; ICE CORE RECORDS", "locations": "South Pole", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Schaefer, Joerg; Steig, Eric J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: A High-sensitivity Beryllium-10 Record from an Ice Core at South Pole", "uid": "p0010158", "west": -180.0}, {"awards": "1443329 Balco, Gregory; 1443321 Bromley, Gordon", "bounds_geometry": "POLYGON((-180 -85.40705,-179.659078 -85.40705,-179.318156 -85.40705,-178.977234 -85.40705,-178.636312 -85.40705,-178.29539 -85.40705,-177.954468 -85.40705,-177.613546 -85.40705,-177.272624 -85.40705,-176.931702 -85.40705,-176.59078 -85.40705,-176.59078 -85.422615,-176.59078 -85.43818,-176.59078 -85.453745,-176.59078 -85.46931,-176.59078 -85.484875,-176.59078 -85.50044,-176.59078 -85.516005,-176.59078 -85.53157,-176.59078 -85.547135,-176.59078 -85.5627,-176.931702 -85.5627,-177.272624 -85.5627,-177.613546 -85.5627,-177.954468 -85.5627,-178.29539 -85.5627,-178.636312 -85.5627,-178.977234 -85.5627,-179.318156 -85.5627,-179.659078 -85.5627,180 -85.5627,179.277561 -85.5627,178.555122 -85.5627,177.832683 -85.5627,177.110244 -85.5627,176.387805 -85.5627,175.665366 -85.5627,174.942927 -85.5627,174.220488 -85.5627,173.498049 -85.5627,172.77561 -85.5627,172.77561 -85.547135,172.77561 -85.53157,172.77561 -85.516005,172.77561 -85.50044,172.77561 -85.484875,172.77561 -85.46931,172.77561 -85.453745,172.77561 -85.43818,172.77561 -85.422615,172.77561 -85.40705,173.498049 -85.40705,174.220488 -85.40705,174.942927 -85.40705,175.665366 -85.40705,176.387805 -85.40705,177.110244 -85.40705,177.832683 -85.40705,178.555122 -85.40705,179.277561 -85.40705,-180 -85.40705))", "dataset_titles": "Interface for viewing observational data related to exposure ages measurements and calculated geologic ages derived therefrom", "datasets": [{"dataset_uid": "200199", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface for viewing observational data related to exposure ages measurements and calculated geologic ages derived therefrom", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Sun, 20 Dec 2020 00:00:00 GMT", "description": "This investigation will reconstruct past behavior of the East Antarctic Ice Sheet during periods of warmer-than-present climate, such as the Pliocene, in order to better project the likely response of Earth\u0027s largest ice sheet to anthropogenic warming. Containing the equivalent of ~55 m sea-level rise, the future evolution of the East Antarctic Ice Sheet has clear societal ramifications on a global scale as temperatures continue to rise. Therefore, determining ice-sheet sensitivity to climate on the scale predicted for the next two centuries is a matter of increasing urgency, particularly in light of evidence suggesting the East Antarctic Ice Sheet is more dynamic than previously thought. This research will provide a terrestrial geologic record of long-term ice-sheet behavior from sites immediately adjacent the East Antarctic Ice Sheet in the Transantarctic Mountains, with which the project will help ascertain how the ice sheet responded to past warm periods. The project will focus primarily on the Pliocene warm period, 5 to 3 million years ago, as this represents the closest analogue to 21st Century climate conditions. The proposed research will investigate glacial deposits corresponding to the East Antarctic Ice Sheet in the central Transantarctic Mountains in order to expand the geologic record of past ice-sheet behavior. The overarching research objectives are to improve understanding of the East Antarctic Ice Sheet\u0027s configuration during periods of warmer-than-present climate, such as the Pliocene warm period, and to determine whether the ice sheet underwent significant volume changes or remained relatively stable in response to warming. To address these goals, the investigation will map and date glacial deposits preserved at mountain sites immediately adjacent the ice sheet. Specifically, we will: (i) employ multiple cosmogenic nuclides (10Be, 26Al, 21Ne) to establish more fully ice-thickness histories for the upper Shackleton and Beardmore Glaciers, where they exit the ice sheet; (ii) use this record to identify periods during which the East Antarctic Ice Sheet was at least as extensive as today; and (iii) use these data to assess long-term ice-sheet variability in East Antarctica, with particular emphasis on Pliocene warm episodes. This research will require Antarctic fieldwork, glacial-geologic mapping, and cosmogenic surface-exposure dating.", "east": -176.59078, "geometry": "POINT(178.092415 -85.484875)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; Transantarctic Mountains; GLACIERS/ICE SHEETS; AMD; GLACIER THICKNESS/ICE SHEET THICKNESS; GLACIER ELEVATION/ICE SHEET ELEVATION; NOT APPLICABLE; Antarctica", "locations": "Antarctica; Transantarctic Mountains", "north": -85.40705, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Balco, Gregory; Bromley, Gorden; BROMLEY, GORDON", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -85.5627, "title": "Collaborative Research: Potential Direct Geologic Constraint of Ice Sheet Thickness in the Central Transantarctic Mountains during the Pliocene Warm Period", "uid": "p0010153", "west": 172.77561}, {"awards": "1644197 Simms, Alexander", "bounds_geometry": "POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))", "dataset_titles": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches; Granulometry of Joinville and Livingston Island beaches; Ground-Penetrating Radar data from Livingston Island in the Antarctic Peninsula; Ground Penetrating Radar Profiles from Beaches on Joinville Island, Antarctic Peninsula; Joinville and Livingston Islands - rock and sediment OSL ages; OSL data - Joinville and Livingston Islands - Raw data; Radiocarbon Ages from Beaches on Joinville Island, Antarctic Peninsula", "datasets": [{"dataset_uid": "601534", "doi": "10.15784/601534", "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "people": "DeWitt, Regina", "repository": "USAP-DC", "science_program": null, "title": "Joinville and Livingston Islands - rock and sediment OSL ages", "url": "https://www.usap-dc.org/view/dataset/601534"}, {"dataset_uid": "601400", "doi": "10.15784/601400", "keywords": "Antarctica; Grain Size; Granulometry; Joinville Island; Livingston Island; LMG0412; Raised Beaches", "people": "Simms, Alexander; Theilen, Brittany", "repository": "USAP-DC", "science_program": null, "title": "Granulometry of Joinville and Livingston Island beaches", "url": "https://www.usap-dc.org/view/dataset/601400"}, {"dataset_uid": "601531", "doi": "10.15784/601531", "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "people": "DeWitt, Regina", "repository": "USAP-DC", "science_program": null, "title": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches", "url": "https://www.usap-dc.org/view/dataset/601531"}, {"dataset_uid": "601532", "doi": "10.15784/601532", "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "people": "DeWitt, Regina", "repository": "USAP-DC", "science_program": null, "title": "OSL data - Joinville and Livingston Islands - Raw data", "url": "https://www.usap-dc.org/view/dataset/601532"}, {"dataset_uid": "601632", "doi": "10.15784/601632", "keywords": "Antarctica; Joinville Island", "people": "Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Ground Penetrating Radar Profiles from Beaches on Joinville Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601632"}, {"dataset_uid": "601633", "doi": "10.15784/601633", "keywords": "Antarctica; Joinville Island", "people": "Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Ground-Penetrating Radar data from Livingston Island in the Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601633"}, {"dataset_uid": "601634", "doi": "10.15784/601634", "keywords": "Antarctica; Joinville Island; Raised Beaches; Sea Level", "people": "Simms, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon Ages from Beaches on Joinville Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601634"}], "date_created": "Thu, 08 Oct 2020 00:00:00 GMT", "description": "Nontechnical Description Glacier ice loss from Antarctica has the potential to lead to a significant rise in global sea level. One line of evidence for accelerated glacier ice loss has been an increase in the rate at which the land has been rising across the Antarctic Peninsula as measured by GPS receivers. However, GPS observations of uplift are limited to the last two decades. One goal of this study is to determine how these newly observed rates of uplift compare to average rates of uplift across the Antarctic Peninsula over a longer time interval. Researchers will reconstruct past sea levels using the age and elevation of ancient beaches now stranded above sea level on the low-lying coastal hills of the Antarctica Peninsula to determine the rate of uplift over the last 5,000 years. The researchers will also analyze the structure of the beaches using ground-penetrating radar and the characteristics of beach sediments to understand how sea-level rise and past climate changes are recorded in beach deposits. The benefits of these new records will be threefold: (1) they will help determine the natural variability of the Antarctic Ice Sheet and relative sea level (2) they will provide new insight about uplift and the structure of the Earth\u0027s interior; and 3) they will help researchers refine the methods used to determine the age of geologic deposits. The study results will be shared in outreach events at K-12 schools and with visitors of the Santa Barbara Natural History Museum. Three graduate students will be supported through this project. Technical description Paleo sea-level data is critical for reconstructing the size and extent of past ice sheets, documenting increased uplift following glacial retreat, and correcting gravity-based measurements of ice-mass loss for the impacts of post-glacial rebound. However, there are only 14 sites with relative sea-level data for Antarctica compared to over 500 sites used in a recent study of the North American Ice-Sheet complex. The purpose of this project is to use optically stimulated luminescence to date a series of newly discovered raised beaches along the eastern Antarctic Peninsula and an already known, but only preliminarily dated, series of raised beaches in the South Shetland Islands. Data to be collected at the raised beaches include the age and elevation, ground-penetrating radar profiles, and the roundness of cobbles and the lithology of ice-rafted debris. The study will test three hypotheses: (1) uplift rates have increased in modern times relative to the late Holocene across the Antarctic Peninsula, (2) the sea-level history at the northern tip of the Antarctic Peninsula is distinctly different than that of the South Shetland Islands, and (3) cobble roundness and the source of ice-rafted debris on raised beaches varied systematically through time reflecting the climate history of the northern Antarctic Peninsula.", "east": -55.0, "geometry": "POINT(-60 -63)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "Antarctic Peninsula; COASTAL LANDFORMS/PROCESSES; USAP-DC; SEA LEVEL RECONSTRUCTION; South Shetland Islands; AMD; FIELD INVESTIGATION; Amd/Us; USA/NSF", "locations": "South Shetland Islands; Antarctic Peninsula", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Simms, Alexander; DeWitt, Regina", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "uid": "p0010132", "west": -65.0}, {"awards": "1542962 Anderson, Robert", "bounds_geometry": "POLYGON((-171 -57,-170.8 -57,-170.6 -57,-170.4 -57,-170.2 -57,-170 -57,-169.8 -57,-169.6 -57,-169.4 -57,-169.2 -57,-169 -57,-169 -57.72,-169 -58.44,-169 -59.16,-169 -59.88,-169 -60.6,-169 -61.32,-169 -62.04,-169 -62.76,-169 -63.48,-169 -64.2,-169.2 -64.2,-169.4 -64.2,-169.6 -64.2,-169.8 -64.2,-170 -64.2,-170.2 -64.2,-170.4 -64.2,-170.6 -64.2,-170.8 -64.2,-171 -64.2,-171 -63.48,-171 -62.76,-171 -62.04,-171 -61.32,-171 -60.6,-171 -59.88,-171 -59.16,-171 -58.44,-171 -57.72,-171 -57))", "dataset_titles": "Expedition Data of NBP1702; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "datasets": [{"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "200165", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "url": "https://www.bco-dmo.org/dataset/813379/data"}, {"dataset_uid": "200166", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ", "url": "https://www.ncdc.noaa.gov/paleo/study/31312"}], "date_created": "Fri, 25 Sep 2020 00:00:00 GMT", "description": "Scientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth\u0027s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. Work proposed here will test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement will be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work will contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. The proposed work will add a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that will collect sediment cores at three to five locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170\u00b0W. The goal is to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. In the proposed work the radiocarbon age of foraminifera that inhabited the surface ocean will be compared with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms will be used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it is expected that surface and deep-dwelling foraminifera will exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters return to the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work is to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean?s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarcitca.", "east": -169.0, "geometry": "POINT(-170 -60.6)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; SEDIMENT CHEMISTRY; South Pacific Ocean; SHIPS", "locations": "South Pacific Ocean", "north": -57.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Fleisher, Martin; Pavia, Frank", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "BCO-DMO; NCEI; R2R", "science_programs": null, "south": -64.2, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean", "uid": "p0010130", "west": -171.0}, {"awards": "0125602 Padman, Laurence; 0125252 Padman, Laurence", "bounds_geometry": "POLYGON((-180 -40.231,-144 -40.231,-108 -40.231,-72 -40.231,-36 -40.231,0 -40.231,36 -40.231,72 -40.231,108 -40.231,144 -40.231,180 -40.231,180 -45.2079,180 -50.1848,180 -55.1617,180 -60.1386,180 -65.1155,180 -70.0924,180 -75.0693,180 -80.0462,180 -85.0231,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -85.0231,-180 -80.0462,-180 -75.0693,-180 -70.0924,-180 -65.1155,-180 -60.1386,-180 -55.1617,-180 -50.1848,-180 -45.2079,-180 -40.231))", "dataset_titles": "Antarctic Tide Gauge Database, version 1; AntTG_Database_Tools; CATS2008: Circum-Antarctic Tidal Simulation version 2008; CATS2008_v2023: Circum-Antarctic Tidal Simulation 2008, version 2023; pyTMD; TMD_Matlab_Toolbox_v2.5", "datasets": [{"dataset_uid": "601358", "doi": "10.15784/601358", "keywords": "Antarctica; Oceans; Sea Surface Height; Tide Gauges; Tides", "people": "Padman, Laurence; King, Matt; Howard, Susan L.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Tide Gauge Database, version 1", "url": "https://www.usap-dc.org/view/dataset/601358"}, {"dataset_uid": "200158", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "pyTMD", "url": "https://github.com/tsutterley/pyTMD"}, {"dataset_uid": "601235", "doi": "10.15784/601235", "keywords": "Antarctica; Inverse Modeling; Model Data; Ocean Currents; Sea Surface; Tidal Models; Tides", "people": "Howard, Susan L.; Padman, Laurence; Erofeeva, Svetlana", "repository": "USAP-DC", "science_program": null, "title": "CATS2008: Circum-Antarctic Tidal Simulation version 2008", "url": "https://www.usap-dc.org/view/dataset/601235"}, {"dataset_uid": "200156", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "AntTG_Database_Tools", "url": "https://github.com/EarthAndSpaceResearch/AntTG_Database_Tools"}, {"dataset_uid": "601772", "doi": "10.15784/601772", "keywords": "Antarctica; Cryosphere; Inverse Modeling; Model Data; Ocean Currents; Oceans; Sea Surface; Southern Ocean; Tide Model; Tides", "people": "Erofeeva, Svetlana; Howard, Susan L.; Greene, Chad A.; Padman, Laurence; Sutterley, Tyler", "repository": "USAP-DC", "science_program": null, "title": "CATS2008_v2023: Circum-Antarctic Tidal Simulation 2008, version 2023", "url": "https://www.usap-dc.org/view/dataset/601772"}, {"dataset_uid": "200157", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "TMD_Matlab_Toolbox_v2.5", "url": "https://github.com/EarthAndSpaceResearch/TMD_Matlab_Toolbox_v2.5"}], "date_created": "Tue, 07 Jul 2020 00:00:00 GMT", "description": "The ocean tide is a large component of total variability of ocean surface height and currents in the seas surrounding Antarctica, including under the floating ice shelves. Maximum tidal height range exceeds 7 m (near the grounding line of Rutford Ice Stream) and maximum tidal currents exceed 1 m/s (near the shelf break in the northwest Ross Sea). Tides contribute to several important climate and ecosystems processes including: ocean mixing, production of dense bottom water, flow of warm Circumpolar Deep Water onto the continental shelves, melting at the bases of ice shelves, fracturing of the ice sheet near a glacier or ice stream\u2019s grounding line, production and decay of sea ice, and sediment resuspension. Tide heights and, in particular, currents can change as the ocean background state changes, and as the geometry of the coastal margins of the Antarctic Ice Sheet varies through ice shelf thickness changes and ice-front and grounding-line advances or retreats. For satellite-based studies of ocean surface height and ice shelf thickness changes, tide heights are a source of substantial noise that must be removed. Similarly, tidal currents can also be a substantial noise signal when trying to estimate mean ocean currents from short-term measurements such as from acoustic Doppler current profilers mounted on ships and CTD rosettes. Therefore, tide models play critical roles in understanding current and future ocean and ice states, and as a method for removing tides in various measurements. A paper in Reviews of Geophysics (Padman, Siegfried and Fricker, 2018, see list of project-related publications below) provides a detailed review of tides and tidal processes around Antarctica.\r\n\nThis project provides a gateway to tide models and a database of tide height coefficients at the Antarctic Data Center, and links to toolboxes to work with these models and data.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e GAUGES \u003e TIDE GAUGES", "is_usap_dc": true, "keywords": "Tide Gauges; OCEAN CURRENTS; Sea Surface Height; USAP-DC; GLACIER MOTION/ICE SHEET MOTION; Tides; Antarctica; MODELS; FIELD INVESTIGATION", "locations": "Antarctica", "north": -40.231, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Arctic System Science", "paleo_time": null, "persons": "Howard, Susan L.; Padman, Laurence; Erofeeva, Svetlana; King, Matt", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "GitHub; USAP-DC", "science_programs": null, "south": -90.0, "title": "Ocean Tides around Antarctica and in the Southern Ocean", "uid": "p0010116", "west": -180.0}, {"awards": "1235094 Thurnherr, Andreas", "bounds_geometry": "POLYGON((-19 -19,-18.2 -19,-17.4 -19,-16.6 -19,-15.8 -19,-15 -19,-14.2 -19,-13.4 -19,-12.6 -19,-11.8 -19,-11 -19,-11 -19.4,-11 -19.8,-11 -20.2,-11 -20.6,-11 -21,-11 -21.4,-11 -21.8,-11 -22.2,-11 -22.6,-11 -23,-11.8 -23,-12.6 -23,-13.4 -23,-14.2 -23,-15 -23,-15.8 -23,-16.6 -23,-17.4 -23,-18.2 -23,-19 -23,-19 -22.6,-19 -22.2,-19 -21.8,-19 -21.4,-19 -21,-19 -20.6,-19 -20.2,-19 -19.8,-19 -19.4,-19 -19))", "dataset_titles": "Expedition Data; NBP1406 Expedition data; NBP1508 Expedition data; Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508; Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015); Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "datasets": [{"dataset_uid": "601354", "doi": "10.15784/601354", "keywords": "Current Measurements; LADCP; Mid-Ocean Ridge; NBP1508; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; South Atlantic Ocean", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601354"}, {"dataset_uid": "001408", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "601353", "doi": null, "keywords": "CTD; CTD Data; Current Measurements; Current Meter; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015)", "url": "https://www.usap-dc.org/view/dataset/601353"}, {"dataset_uid": "200153", "doi": "10.7284/903009", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1406 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "200154", "doi": "10.7284/906708", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1508 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1508"}, {"dataset_uid": "601352", "doi": null, "keywords": "CTD; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601352"}], "date_created": "Thu, 02 Jul 2020 00:00:00 GMT", "description": "Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced \"fracture zone canyons\" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation.", "east": -11.0, "geometry": "POINT(-15 -21)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN CURRENTS; South Atlantic Ocean; R/V NBP; WATER MASSES", "locations": "South Atlantic Ocean", "north": -19.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Thurnherr, Andreas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -23.0, "title": "Collaborative Research: Flow, Turbulence and Mixing in Mid-Ocean Ridge Fracture Zone Canyons", "uid": "p0010114", "west": -19.0}, {"awards": "1341658 Mukhopadhyay, Sujoy", "bounds_geometry": "POLYGON((-116.45 -84.786,-116.443 -84.786,-116.436 -84.786,-116.429 -84.786,-116.422 -84.786,-116.415 -84.786,-116.408 -84.786,-116.401 -84.786,-116.394 -84.786,-116.387 -84.786,-116.38 -84.786,-116.38 -84.7864,-116.38 -84.7868,-116.38 -84.7872,-116.38 -84.7876,-116.38 -84.788,-116.38 -84.7884,-116.38 -84.7888,-116.38 -84.7892,-116.38 -84.7896,-116.38 -84.79,-116.387 -84.79,-116.394 -84.79,-116.401 -84.79,-116.408 -84.79,-116.415 -84.79,-116.422 -84.79,-116.429 -84.79,-116.436 -84.79,-116.443 -84.79,-116.45 -84.79,-116.45 -84.7896,-116.45 -84.7892,-116.45 -84.7888,-116.45 -84.7884,-116.45 -84.788,-116.45 -84.7876,-116.45 -84.7872,-116.45 -84.7868,-116.45 -84.7864,-116.45 -84.786))", "dataset_titles": "Ohio Range Subglacial rock core cosmogenic nuclide data", "datasets": [{"dataset_uid": "601351", "doi": "10.15784/601351", "keywords": "Aluminum-26; Antarctica; Beryllium-10; Cosmogenic Dating; Cosmogenic Radionuclides; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Fluctuations; Ohio Range; Rocks", "people": "Mukhopadhyay, Sujoy", "repository": "USAP-DC", "science_program": null, "title": "Ohio Range Subglacial rock core cosmogenic nuclide data", "url": "https://www.usap-dc.org/view/dataset/601351"}], "date_created": "Sun, 28 Jun 2020 00:00:00 GMT", "description": "Modeling fluctuations in the extent of the West Antarctic Ice Sheet (WAIS) over time is a principal goal of the glaciological community. These models will provide a critical basis for predictions of future sea level change, and therefore this work great societal relevance. The mid-Pliocene time interval is of particular interest, as it is the most recent period in which global temperatures were warmer and atmospheric CO2 concentrations may have been higher than current levels. However, observational constraints on fluctuations in the WAIS older than the last glacial maximum are rare. The investigators propose to collect geochemical data from the Ohio Range and Scott Glacier to quantify past variability in the height of the WAIS. Limited available cosmogenic nuclide data are broadly consistent with a model indicating that Pliocene WAIS elevations and volumes were smaller than at present, and that WAIS collapse was common. The PIs will use geologic observations and cosmogenic nuclide concentrations from bedrock samples at multiple locations and at multiple elevations, including sub-ice samples, to constrain WAIS ice volume changes in a \"dipstick\" like fashion. Data obtained from the proposed research will provide targets for data-ice sheet model comparisons to accurately characterize Plio-Pleistocene and future WAIS behavior. As part of this project, the investigators will work with the Natural History Museum and the Earth \u0026 Planetary Science department at Harvard to develop an exhibit that will become part of the Museum\u0027s recently opened Earth and Planetary Science Gallery. The project involves mentoring of a female graduate student as well as an undergraduate student.", "east": -116.38, "geometry": "POINT(-116.415 -84.788)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ROCK CORERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e AMS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Sheet Fluctuations; ALUMINUM-26 ANALYSIS; BERYLLIUM-10 ANALYSIS; Cosmogenic Radionuclides; USAP-DC; FIELD INVESTIGATION; AMD; Ohio Range; GLACIER THICKNESS/ICE SHEET THICKNESS; ICE SHEETS; LABORATORY", "locations": "Ohio Range", "north": -84.786, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Mukhopadhyay, Sujoy", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.79, "title": "Constraining Plio-Pleistocene West Antarctic Ice Sheet Behavior from the Ohio Range and Scott Glacier", "uid": "p0010113", "west": -116.45}, {"awards": "1142167 Pettit, Erin; 1142035 Obbard, Rachel", "bounds_geometry": "POLYGON((-112.3 -79.2,-112.2 -79.2,-112.1 -79.2,-112 -79.2,-111.9 -79.2,-111.8 -79.2,-111.7 -79.2,-111.6 -79.2,-111.5 -79.2,-111.4 -79.2,-111.3 -79.2,-111.3 -79.23,-111.3 -79.26,-111.3 -79.29,-111.3 -79.32,-111.3 -79.35,-111.3 -79.38,-111.3 -79.41,-111.3 -79.44,-111.3 -79.47,-111.3 -79.5,-111.4 -79.5,-111.5 -79.5,-111.6 -79.5,-111.7 -79.5,-111.8 -79.5,-111.9 -79.5,-112 -79.5,-112.1 -79.5,-112.2 -79.5,-112.3 -79.5,-112.3 -79.47,-112.3 -79.44,-112.3 -79.41,-112.3 -79.38,-112.3 -79.35,-112.3 -79.32,-112.3 -79.29,-112.3 -79.26,-112.3 -79.23,-112.3 -79.2))", "dataset_titles": "ApRES Firn Density Study; ApRES Vertical Strain Study; GPS Horizontal Strain Network; South Pole (SPICEcore) Borehole Deformation; WAIS Divide Borehole Deformation", "datasets": [{"dataset_uid": "601315", "doi": "10.15784/601315", "keywords": "Acoustic Televiewer; Anisotropy; Antarctica; Borehole Logging; Deformation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Flow; Snow/ice; Snow/Ice; South Pole; SPICEcore", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPICEcore) Borehole Deformation", "url": "https://www.usap-dc.org/view/dataset/601315"}, {"dataset_uid": "200141", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "GPS Horizontal Strain Network", "url": ""}, {"dataset_uid": "601314", "doi": "10.15784/601314", "keywords": "Acoustic Televiewer; Anisotropy; Antarctica; Borehole Logging; Deformation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Flow; WAIS Divide; WAIS Divide Ice Core", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Borehole Deformation", "url": "https://www.usap-dc.org/view/dataset/601314"}, {"dataset_uid": "601322", "doi": "10.15784/601322", "keywords": "Antarctica; Firn; Firn Density; Glaciology; Ice Penetrating Radar; Phase Sensitive Radar; Radar; Snow/ice; Snow/Ice; WAIS Divide", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "ApRES Firn Density Study", "url": "https://www.usap-dc.org/view/dataset/601322"}, {"dataset_uid": "601323", "doi": "10.15784/601323", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Penetrating Radar; Ice Strain; Phase Sensitive Radar; Radar; Snow/ice; Snow/Ice; WAIS Divide", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "ApRES Vertical Strain Study", "url": "https://www.usap-dc.org/view/dataset/601323"}], "date_created": "Fri, 15 May 2020 00:00:00 GMT", "description": "1142167/Pettit This award supports a project to develop a better understanding of the relation between ice microstructure, impurities, and ice flow and their connection to climate history for the West Antarctic Ice Sheet (WAIS) ice core site. This work builds on several ongoing studies at Siple Dome in West Antarctica and Dome C in East Antarctica. It is well known that the microstructure of ice evolves with depth and time in an ice sheet. This evolution of microstructure depends on the ice flow field, temperature, and impurity content. The ice flow field, in turn, depends on microstructure, leading to feedbacks that create layered variation in microstructure that relates to climate and flow history. The research proposed here focuses on developing a better understanding of: 1) how ice microstructure evolves with time and stress in an ice sheet and how that relates to impurity content, temperature, and strain rate; 2) how variations in ice microstructure and impurity content affect ice flow patterns near ice divides (on both small (1cm to 1m) and large (1m to 100km) scales); and 3) in what ways is the spatial variability of ice microstructure and its effect on ice flow important for interpretation of climate history in the WAIS Divide ice core. The study will integrate existing ice core and borehole data with a detailed study of ice microstructure using Electron Backscatter Diffraction (EBSD) techniques and measurements of borehole deformation through time using Acoustic Televiewers. This will be the first study to combine these two novel techniques for studying the relation between microstructure and deformation and it will build on other data being collected as part of other WAIS Divide borehole logging projects (e.g. sonic velocity, optical dust logging, temperature and other measurements on the ice core including fabric measurements from thin section analyses as well as studies of ice chemistry and stable isotopes. The intellectual merit of the work is that it will improve interpretation of ice core data (especially information on past accumulation) and overall understanding of ice flow. The broader impacts are that the work will ultimately contribute to a better interpretation of ice core records for both paleoclimate studies and for ice flow history, both of which connect to the broader questions of the role of ice in the climate system. The work will also advance the careers of two early-career female scientists, including one with a hearing impairment disability. This project will support a PhD student at the UAF and provide research and field experience for two or three undergraduates at Dartmouth. The PIs plan to include a teacher on their field team and collaborate with UAF\u0027s \"From STEM to STEAM\" toward enhancing the connection between art and science.", "east": -111.3, "geometry": "POINT(-111.8 -79.35)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; GLACIERS/ICE SHEETS; WAIS Divide; ICE CORE RECORDS; USAP-DC; GLACIER MOTION/ICE SHEET MOTION; Radar", "locations": "WAIS Divide", "north": -79.2, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Pettit, Erin; Obbard, Rachel", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "UNAVCO; USAP-DC", "science_programs": "WAIS Divide Ice Core; SPICEcore", "south": -79.5, "title": "Collaborative Research: VeLveT Ice - eVoLution of Fabric and Texture in Ice at WAIS Divide, West Antarctica", "uid": "p0010098", "west": -112.3}, {"awards": "9615832 Blankenship, Donald; 9615704 Bell, Robin", "bounds_geometry": "POLYGON((-180 -74,-176 -74,-172 -74,-168 -74,-164 -74,-160 -74,-156 -74,-152 -74,-148 -74,-144 -74,-140 -74,-140 -75.6,-140 -77.2,-140 -78.8,-140 -80.4,-140 -82,-140 -83.6,-140 -85.2,-140 -86.8,-140 -88.4,-140 -90,-144 -90,-148 -90,-152 -90,-156 -90,-160 -90,-164 -90,-168 -90,-172 -90,-176 -90,180 -90,174 -90,168 -90,162 -90,156 -90,150 -90,144 -90,138 -90,132 -90,126 -90,120 -90,120 -88.4,120 -86.8,120 -85.2,120 -83.6,120 -82,120 -80.4,120 -78.8,120 -77.2,120 -75.6,120 -74,126 -74,132 -74,138 -74,144 -74,150 -74,156 -74,162 -74,168 -74,174 -74,-180 -74))", "dataset_titles": "SOAR-PPT Airborne gravity data; SOAR-WLK Airborne gravity data", "datasets": [{"dataset_uid": "601293", "doi": "10.15784/601293", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Potential Field; Solid Earth; Transantarctic Mountains", "people": "Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-WLK Airborne gravity data", "url": "https://www.usap-dc.org/view/dataset/601293"}, {"dataset_uid": "601292", "doi": "10.15784/601292", "keywords": "Aerogeophysics; Airborne Gravity; Airplane; Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Gravity Data; Potential Field; Solid Earth; Transantarctic Mountains", "people": "Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-PPT Airborne gravity data", "url": "https://www.usap-dc.org/view/dataset/601292"}], "date_created": "Fri, 24 Apr 2020 00:00:00 GMT", "description": "Bell and Buck: OPP 9615704 Blankenship: OPP 9615832 Abstract Continental extension produces a great variety of structures from the linear narrow rifts of the East African Rift to the diffuse extension of the Basin and Range Province of the Western U.S. Rift shoulder uplift varies dramatically between rift flanks. The cause of variable rift width and crustal thinning is fairly well explained by variable initial heat flow and crustal thickness. Mechanical stretching of the lithosphere has been linked to rift shoulder uplift but the cause of variable rift flank uplift remains poorly understood. The Transantarctic Mountains (TAM) are an extreme example of rift flank uplift, extending over 3500 km across Antarctica and reaching elevations up to 4500 m and thus constitute a unique feature of EarthOs crust. The range was formed in the extensional environment associated with the Mesozoic and Cenozoic breakup of Gondwanaland. Geological and geophysical work has shown that the TAM developed along the long-lived lithospheric boundary between East and West Antarctica reactivated by a complex history of extensional and translational microplate motions. The TAM are not uniform along strike. Along the OWilkes FrontO, the northern segment of the rift extends from North Victoria Land to Byrd Glacier. The Wilkes Front architecture consists of (1) thin, extended crust forming the Victoria Land Basin in the Ross Sea, (2) the TAM rift shoulder, and (3) a long-wavelength down- ward forming the Wilkes Basin. Contrasting structures are mapped along the OPensacola/PoleO Front, the southern segment of the rift extending from the Nimrod Glacier to the Pensacola Mountains. Along this southern section no rift basin has been mapped to date and the down-ward along the East Antarctic, or ObacksideO, edge of the mountains is less pronounced. A flexural model linking the extension in the Ross Sea to the formation of both the mountains and the Wilkes Basin has been considered as a me chanism for uplift of the entire mountain range. The variability in fundamental architecture along the TAM indicates that neither a single event nor a sequence of identical events produced the rift flank uplift. The observation of variable architecture suggests complex mechanisms and possibly a fundamental limitation in maximum sustainable rift flank elevation. The motivation for studying the TAM is to try to understand the geodynamics of this extreme elevation rift flank. Are the geodynamics of the area unique, or does the history of glaciation and related erosion contribute to the extreme uplift? With the existing data sets it is difficult to confidently constrain the geological architecture across representative sections of the TAM. Any effort to refine geodynamic mechanisms requires this basic understanding of the TAM architecture. The goal of this project is to (1) constrain the architecture of the rift system as well as the distribution and structure of sedimentary basins, glacial erosion and mafic igneous rocks surrounding the rift flank by acquiring three long wavelength geophysical transects with integrated gravity, magnetics, ice- penetrating radar, and ice surface measurements, (2) quantify the contribution of various geodynamic mechanisms to understand the geological conditions which can lead to extreme rift flank uplift, and (3) use the improved understanding of architecture and geophysical data to test geodynamic models in order to improve our understanding both of the TAM geodynamics and the general problem of the geodynamics of rift flank uplift worldwide. This project will allow development of a generalized framework for understanding the development of rift flank uplift as well as address the question of the specific geodynamic evolution of the TAM.", "east": -140.0, "geometry": "POINT(170 -82)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": true, "keywords": "USAP-DC; Transantarctic Mountains; GRAVITY FIELD; TECTONICS", "locations": "Transantarctic Mountains", "north": -74.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bell, Robin; Buck, W. Roger; Blankenship, Donald D.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Contrasting Architecture and Dynamics of the Transantarctic Mountains", "uid": "p0010095", "west": 120.0}, {"awards": "1443470 Aydin, Murat", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "South Pole ice core (SPC14) discrete methane data; SP19 Gas Chronology; SPC14 carbonyl sulfide, methyl chloride, and methyl bromide measurements from South Pole, Antarctica", "datasets": [{"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Brook, Edward J.; Kennedy, Joshua A.; Ferris, David G.; Kalk, Michael; Hood, Ekaterina; Fudge, T. J.; Osterberg, Erich; Winski, Dominic A.; Steig, Eric J.; Kahle, Emma; Sowers, Todd A.; Edwards, Jon S.; Aydin, Murat; Kreutz, Karl; Buizert, Christo; Epifanio, Jenna; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601270", "doi": "10.15784/601270", "keywords": "Antarctica", "people": "Aydin, Murat", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPC14 carbonyl sulfide, methyl chloride, and methyl bromide measurements from South Pole, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601270"}], "date_created": "Thu, 26 Mar 2020 00:00:00 GMT", "description": "In the past, Earth\u0027s climate underwent dramatic changes that influenced physical, chemical, geological, and biological processes on a global scale. Such changes left an imprint in Earth\u0027s atmosphere, as shown by the variability in abundances of trace gases like carbon dioxide and methane. In return, changes in the atmospheric trace gas composition affected Earth\u0027s climate. Studying compositional variations of the past atmosphere helps us understand the history of interactions between global biogeochemical cycles and Earth?s climate. The most reliable information on past atmospheric composition comes from analysis of air entrapped in polar ice cores. This project aims to generate ice-core records of relatively short-lived, very-low-abundance trace gases to determine the range of past variability in their atmospheric levels and investigate the changes in global biogeochemical cycles that caused this variability. This project measures three such gases: carbonyl sulfide, methyl chloride, and methyl bromide. Changes in carbonyl sulfide can indicate changes in primary productivity and photosynthetic update of carbon dioxide. Changes in methyl chloride and methyl bromide significantly impact natural variability in stratospheric ozone. In addition, the processes that control atmospheric levels of methyl chloride and methyl bromide are shared with those controlling levels of atmospheric methane. The measurements will be made in the new ice core from the South Pole, which is expected to provide a 40,000-year record. The primary focus of this project is to develop high-quality trace gas records for the entire Holocene period (the past 11,000 years), with additional, more exploratory measurements from the last glacial period including the period from 29,000-36,000 years ago when there were large changes in atmospheric methane. Due to the cold temperatures of the South Pole ice, the proposed carbonyl sulfide measurements are expected to provide a direct measure of the past atmospheric variability of this gas without the large hydrolysis corrections that are necessary for interpretation of measurements from ice cores in warmer settings. Furthermore, we will test the expectation that contemporaneous measurements from the last glacial period in the deep West Antarctic Ice Sheet Divide ice core will not require hydrolysis loss corrections. With respect to methyl chloride, we aim to verify and improve the existing Holocene atmospheric history from the Taylor Dome ice core in Antarctica. The higher resolution of our measurements compared with those from Taylor Dome will allow us to derive a more statistically significant relationship between methyl chloride and methane. With respect to methyl bromide, we plan to extend the existing 2,000-year database to 11,000 years. Together, the methyl bromide and methyl chloride records will provide strong measurement-based constraints on the natural variability of stratospheric halogens during the Holocene period. In addition, the methyl bromide record will provide insight into the correlation between methyl chloride and methane during the Holocene period due to common sources and sinks.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; CARBONYL SULFIDE; HALOCARBONS AND HALOGENS; TRACE GASES/TRACE SPECIES; Antarctic; USAP-DC", "locations": "Antarctic", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Carbonyl Sulfide, Methyl Chloride, and Methyl Bromide Measurements in the New Intermediate-depth South Pole Ice Core", "uid": "p0010089", "west": -180.0}, {"awards": "1341432 Brzezinski, Mark; 1341464 Robinson, Rebecca", "bounds_geometry": "POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))", "dataset_titles": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments; Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S; Expedition Data of NBP1702; Particle composition measurements from along 170\u00b0W between 67-54\u00b0S; Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "datasets": [{"dataset_uid": "601522", "doi": "10.15784/601522", "keywords": "Antarctica; Nitrogen Isotopes; Oceans; Paleoproxies; Southern Ocean", "people": "Kelly, Roger; Robinson, Rebecca ; Riesselman, Christina; Jones, Colin; Closset, Ivia; Robinson, Rebecca; Brzezinski, Mark", "repository": "USAP-DC", "science_program": null, "title": "Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "url": "https://www.usap-dc.org/view/dataset/601522"}, {"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "601276", "doi": "10.15784/601276", "keywords": "Antarctica; Biogenic Silica; Nitrogen Isotopes; Southern Ocean", "people": "Robinson, Rebecca; Brzezinski, Mark", "repository": "USAP-DC", "science_program": null, "title": "Particle composition measurements from along 170\u00b0W between 67-54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601276"}, {"dataset_uid": "601269", "doi": "10.15784/601269", "keywords": "Antarctica; Chlorophyll; Southern Ocean", "people": "Robinson, Rebecca; Brzezinski, Mark", "repository": "USAP-DC", "science_program": null, "title": "Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601269"}, {"dataset_uid": "601576", "doi": "10.15784/601576", "keywords": "Antarctica; Biogenic Silica; Chemistry:sediment; Chemistry:Sediment; Diatom; Diatom Bound; Lithogenic Silica; Marine Geoscience; NBP1702; Nitrogen Isotopes; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Closset, Ivia; Brzezinski, Mark; Jones, Janice L.; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": " Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601576"}, {"dataset_uid": "601562", "doi": "10.15784/601562", "keywords": "Antarctica; Biogenic Silica; Chemistry:sediment; Chemistry:Sediment; Lithogenic Silica; Marine Geoscience; NBP1702; Pore Water Biogeochemistry; Sediment; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Closset, Ivia; Brzezinski, Mark; Jones, Janice L.", "repository": "USAP-DC", "science_program": null, "title": "Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601562"}, {"dataset_uid": "601523", "doi": "10.15784/601523", "keywords": "Antarctica; Biota; Carboy Growouts; Diatom; Diatom Assemblage Data; NBP1702; Oceans; R/v Nathaniel B. Palmer; Southern Ocean; Southern Ocean Summer", "people": "Jones, Colin; Riesselman, Christina; Robinson, Rebecca; Robinson, Rebecca ", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments", "url": "https://www.usap-dc.org/view/dataset/601523"}], "date_created": "Wed, 26 Feb 2020 00:00:00 GMT", "description": "Collaborative Proposal: A field and laboratory examination of the diatom N and Si isotope proxies: Implications for assessing the Southern Ocean biological pump The rise in atmospheric carbon dioxide concentrations and associated climate changes make understanding the role of the ocean in large scale carbon cycle a priority. Geologic samples allow exploration of potential mechanisms for carbon dioxide drawdown during glacial periods through the use of geochemical proxies. Nitrogen and silicon isotope signatures from fossil diatoms (microscopic plants) are used to investigate changes in the physical supply and biological demand for nutrients (like nitrogen and silicon and carbon) in the Southern Ocean. The project will evaluate the use the nitrogen and silicon isotope proxies through a series of laboratory experiments and Southern Ocean field sampling. The results will provide quantification of real relationships between nitrogen and silicon isotopes and nutrient usage in the Southern Ocean and allow exploration of the role of other factors, including biological diversity, ice cover, and mixing, in altering the chemical signatures recorded by diatoms. Seafloor sediment samples will be used to evaluate how well the signal created in the water column is recorded by fossil diatoms buried in the seafloor. Improving the nutrient isotope proxies will allow for a more quantitative understanding of the role of polar biology in regulating natural variation in atmospheric carbon dioxide. The project will also result in the training of a graduate student and development of outreach materials targeting a broad popular audience. This project seeks to test the fidelity of the diatom nitrogen and silicon isotope proxies, two commonly used paleoceanographic tools for investigating the role of the Southern Ocean biological pump in regulating atmospheric CO2 concentrations on glacial-interglacial timescales. Existing ground-truthing data, including culture experiments, surface sediment data and downcore reconstructions, all suggest that nutrient utilization is the primary driver of isotopic variation in the Southern Ocean. However, strong contribution of interspecific variation is implied by recent culture results. Moreover, field and laboratory studies present some contradictory results in terms of the relative importance of interspecific variation and of inferred post-depositional alteration of the nutrient isotope signals. Here, a first order test of the N and Si diatom nutrient isotope paleo-proxies, involving water column dissolved and particulate sampling and laboratory culturing of field-isolates, is proposed. Southern Ocean water, biomass, live diatoms and fossil diatom sampling will be conducted to investigate species and assemblage related variability in diatom nitrogen and silicon isotopes and their relationship to surface nutrient fields and early diagenesis. Access to fresh materials produced in an analogous environmental context to the sediments of primary interest is critical for making robust paleoceanographic reconstructions. Field sampling will occur along 175\u00b0W, transecting the Antarctic Circumpolar Current from the subtropics to the marginal ice edge. Collection of water, sinking/suspended particles and multi-core samples from 13 stations and 3 shipboard incubation experiments will be used to test four proposed hypotheses that together evaluate the significance of existing culture results and seek to allow the best use of diatom nutrient isotope proxies in evaluating the biological pump.", "east": -165.0, "geometry": "POINT(-170 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; AMD; NITROGEN ISOTOPES; R/V NBP; NSF/USA; NUTRIENTS; USAP-DC; Amd/Us", "locations": "Southern Ocean", "north": -54.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Rebecca; Brzezinski, Mark", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "uid": "p0010083", "west": -175.0}, {"awards": "1443105 Steig, Eric", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core; South Pole high resolution ice core water stable isotope record for dD, d18O; South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt and Major Ions; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601239", "doi": "10.15784/601239", "keywords": "Antarctica; Cavity Ring Down Spectrometers; Delta 18O; Delta Deuterium; Deuterium Isotopes; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Oxygen Isotope; Snow/ice; Snow/Ice; Stable Isotopes", "people": "Vaughn, Bruce; Schauer, Andrew; Kahle, Emma; Steig, Eric J.; White, James; Morris, Valerie; Jones, Tyler R.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole high resolution ice core water stable isotope record for dD, d18O", "url": "https://www.usap-dc.org/view/dataset/601239"}, {"dataset_uid": "601851", "doi": "10.15784/601851", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Sea Salt and Major Ions", "url": "https://www.usap-dc.org/view/dataset/601851"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "Morris, Valerie; White, James; Epifanio, Jenna; Buizert, Christo; Waddington, Edwin D.; Conway, Howard; Stevens, Max; Schauer, Andrew; Vaughn, Bruce; Koutnik, Michelle; Fudge, T. J.; Jones, Tyler R.; Steig, Eric J.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601429", "doi": "10.15784/601429", "keywords": "Antarctica; Climate; Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrogen; Ice; Ice Core; Ice Core Chemistry; Oxygen; Paleoclimate; Snow/ice; Snow/Ice; South Pole; Stable Isotopes", "people": "White, James; Steig, Eric J.; Schauer, Andrew; Kahle, Emma; Morris, Valerie; Vaughn, Bruce; Jones, Tyler R.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core", "url": "https://www.usap-dc.org/view/dataset/601429"}, {"dataset_uid": "601850", "doi": "10.15784/601850", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601850"}], "date_created": "Sun, 17 Nov 2019 00:00:00 GMT", "description": "This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible. This project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "SPICEcore; D18O; LABORATORY; OXYGEN ISOTOPE ANALYSIS; Oxygen Isotope; South Pole; USAP-DC; GLACIERS/ICE SHEETS; Antarctica; AMD; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Steig, Eric J.; White, James", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole", "uid": "p0010065", "west": 0.0}, {"awards": "1142517 Aydin, Murat; 1142646 Twickler, Mark; 1141839 Steig, Eric", "bounds_geometry": "POINT(90 -90)", "dataset_titles": "South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt and Major Ions; South Pole ice core (SPC14) discrete methane data; South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601850", "doi": "10.15784/601850", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601850"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Brook, Edward J.; Kennedy, Joshua A.; Ferris, David G.; Kalk, Michael; Hood, Ekaterina; Fudge, T. J.; Osterberg, Erich; Winski, Dominic A.; Steig, Eric J.; Kahle, Emma; Sowers, Todd A.; Edwards, Jon S.; Aydin, Murat; Kreutz, Karl; Buizert, Christo; Epifanio, Jenna; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601851", "doi": "10.15784/601851", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Sea Salt and Major Ions", "url": "https://www.usap-dc.org/view/dataset/601851"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "Morris, Valerie; White, James; Epifanio, Jenna; Buizert, Christo; Waddington, Edwin D.; Conway, Howard; Stevens, Max; Schauer, Andrew; Vaughn, Bruce; Koutnik, Michelle; Fudge, T. J.; Jones, Tyler R.; Steig, Eric J.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}, {"dataset_uid": "601221", "doi": "10.15784/601221", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Data; Ice Core Depth; Ice Core Records; Snow/ice; Snow/Ice; SPICEcore", "people": "Twickler, Mark; Souney, Joseph Jr.; Fegyveresi, John; Casey, Kimberly A.; Aydin, Murat; Steig, Eric J.; Nunn, Richard; Hargreaves, Geoff; Fudge, T. J.; Nicewonger, Melinda R.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth", "url": "https://www.usap-dc.org/view/dataset/601221"}], "date_created": "Wed, 30 Oct 2019 00:00:00 GMT", "description": "1142517/Saltzman This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.", "east": 90.0, "geometry": "POINT(90 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; Amd/Us; Antarctica; ANALYTICAL LAB; USA/NSF; AMD; South Pole; ICE CORE RECORDS; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Twickler, Mark; Souney, Joseph Jr.; Aydin, Murat; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: A 1500m Ice Core from South Pole", "uid": "p0010060", "west": 90.0}, {"awards": "1443424 McMahon, Kelton; 1443386 Emslie, Steven; 1443585 Polito, Michael; 1826712 McMahon, Kelton", "bounds_geometry": "POLYGON((-180 -60,-166 -60,-152 -60,-138 -60,-124 -60,-110 -60,-96 -60,-82 -60,-68 -60,-54 -60,-40 -60,-40 -61.8,-40 -63.6,-40 -65.4,-40 -67.2,-40 -69,-40 -70.8,-40 -72.6,-40 -74.4,-40 -76.2,-40 -78,-54 -78,-68 -78,-82 -78,-96 -78,-110 -78,-124 -78,-138 -78,-152 -78,-166 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -76.2,160 -74.4,160 -72.6,160 -70.8,160 -69,160 -67.2,160 -65.4,160 -63.6,160 -61.8,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions; Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s; Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica; Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009; Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula; Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.; Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica; Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.; Receding ice drove parallel expansions in Southern Ocean penguin; SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".; Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica; Stable isotopes of Adelie Penguin chick bone collagen; The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "datasets": [{"dataset_uid": "601232", "doi": "10.15784/601232", "keywords": "Amino Acids; Antarctica; Antarctic Peninsula; Biota; Isotope Data; Nitrogen Isotopes; Oceans; Penguin; Southern Ocean; Stable Isotope Analysis", "people": "McMahon, Kelton; Polito, Michael", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s", "url": "https://www.usap-dc.org/view/dataset/601232"}, {"dataset_uid": "200181", "doi": "10.6084/m9.figshare.c.4475300.v1", "keywords": null, "people": null, "repository": "Figshare", "science_program": null, "title": "SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".", "url": "https://doi.org/10.6084/m9.figshare.c.4475300.v1"}, {"dataset_uid": "601210", "doi": "10.15784/601210", "keywords": "Antarctica; Antarctic Krill; Antarctic Peninsula; Biota; Carbon Isotopes; Isotope Data; Krill; Nitrogen Isotopes; Oceans; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009", "url": "https://www.usap-dc.org/view/dataset/601210"}, {"dataset_uid": "601327", "doi": "10.15784/601327", "keywords": "Adelie Penguin; Antarctica; Biota; Cape Adare; East Antarctica; Population Movement; Pygoscelis Adeliae; Radiocarbon; Ross Sea; Sea Level Rise; Stable Isotopes", "people": "Emslie, Steven D.; McKenzie, Ashley; Patterson, William", "repository": "USAP-DC", "science_program": null, "title": "The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601327"}, {"dataset_uid": "601212", "doi": "10.15784/601212", "keywords": "Abandoned Colonies; Antarctica; Antarctic Peninsula; Beach Deposit; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Holocene; Penguin; Radiocarbon; Radiocarbon Dates; Snow/ice; Snow/Ice; Stranger Point", "people": "Emslie, Steven D.", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601212"}, {"dataset_uid": "200180", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "Receding ice drove parallel expansions in Southern Ocean penguin", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA589336"}, {"dataset_uid": "601913", "doi": "10.15784/601913", "keywords": "Adelie Penguin; Antarctica; Cryosphere; Foraging; Polynya; Pygoscelis Adeliae; Ross Sea; Stable Isotopes", "people": "Powers, Shannon; Emslie, Steven D.; Reaves, Megan", "repository": "USAP-DC", "science_program": null, "title": "Stable isotopes of Adelie Penguin chick bone collagen", "url": "https://www.usap-dc.org/view/dataset/601913"}, {"dataset_uid": "601509", "doi": "10.15784/601509", "keywords": "Antarctica; Antarctic Fur Seal; Elemental Concentrations; King Penguin; Population Dynamics; South Atlantic Ocean; South Georgia Island; Stable Isotope Analysis; Sub-Antarctic", "people": "Maiti, Kanchan; Polito, Michael; McMahon, Kelton; Kristan, Allyson", "repository": "USAP-DC", "science_program": null, "title": "Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.", "url": "https://www.usap-dc.org/view/dataset/601509"}, {"dataset_uid": "601760", "doi": "10.15784/601760", "keywords": "Adelie Penguin; Amino Acids; Antarctica; Antarctic Peninsula; Ross Sea; Stable Isotope Analysis; Trophic Position", "people": "McCarthy, Matthew; Emslie, Steven D.; Michelson, Chantel; Polito, Michael; Wonder, Michael; Patterson, William; McMahon, Kelton", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions", "url": "https://www.usap-dc.org/view/dataset/601760"}, {"dataset_uid": "601364", "doi": "10.15784/601364", "keywords": "Antarctica; Antarctic Peninsula; Arctocephalus Gazella; Carbon; Holocene; Nitrogen; Paleoecology; Penguin; Pygoscelis Spp.; Stable Isotope Analysis; Weddell Sea", "people": "Clucas, Gemma; Polito, Michael; Kalvakaalva, Rohit; Herman, Rachael", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.", "url": "https://www.usap-dc.org/view/dataset/601364"}, {"dataset_uid": "601263", "doi": "10.15784/601263", "keywords": "Abandoned Colonies; Antarctica; Holocene; Penguin; Ross Sea; Stable Isotope Analysis", "people": "Patterson, William; Emslie, Steven D.; Kristan, Allyson", "repository": "USAP-DC", "science_program": null, "title": "Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601263"}, {"dataset_uid": "601374", "doi": "10.15784/601374", "keywords": "Adelie Penguin; Antarctica; Cape Irizar; Drygalski Ice Tongue; Ross Sea; Stable Isotopes", "people": "Emslie, Steven D.", "repository": "USAP-DC", "science_program": null, "title": "Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601374"}, {"dataset_uid": "601382", "doi": "10.15784/601382", "keywords": "25 De Mayo/King George Island; Antarctica; Biota; Delta 13C; Delta 15N; Dietary Shifts; Opportunistic Sampling; Penguin; Pygoscelis Penguins; Stranger Point", "people": "Ciriani, Yanina; Emslie, Steven D.", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica", "url": "https://www.usap-dc.org/view/dataset/601382"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (\u003c20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change. This research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.", "east": -40.0, "geometry": "POINT(-120 -69)", "instruments": null, "is_usap_dc": true, "keywords": "ANIMAL ECOLOGY AND BEHAVIOR; South Shetland Islands; Penguin; Stable Isotopes; Polar; Ross Sea; USA/NSF; Weddell Sea; AMD; MARINE ECOSYSTEMS; USAP-DC; Antarctica; PENGUINS; Southern Hemisphere; FIELD INVESTIGATION; Amd/Us; Krill; MACROFOSSILS", "locations": "Southern Hemisphere; Ross Sea; South Shetland Islands; Weddell Sea; Polar; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Polito, Michael; Kelton, McMahon; Patterson, William; McCarthy, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "Figshare; NCBI BioProject; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "uid": "p0010047", "west": 160.0}, {"awards": "1643901 Zhang, Weifeng; 2021245 Li, Yun; 1643735 Li, Yun", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Dynamic fine-scale sea-icescape shapes adult emperor penguin foraging habitat in East Antarctica; Monthly Stratification Climatology (1978-2021) in Antarctic Coastal Polynyas", "datasets": [{"dataset_uid": "601628", "doi": "10.15784/601628", "keywords": "Antarctic; Antarctica; Antarctic Coastal Polynyas; Polynya", "people": "Shunk, Nathan; Li, Yun; Zhang, Weifeng", "repository": "USAP-DC", "science_program": null, "title": "Monthly Stratification Climatology (1978-2021) in Antarctic Coastal Polynyas", "url": "https://www.usap-dc.org/view/dataset/601628"}, {"dataset_uid": "601209", "doi": "10.15784/601209", "keywords": "Animal Behavior Observation; Antarctica; Biota; East Antarctica; GPS; Oceans; Penguin; Southern Ocean", "people": "Bost, Charles-Andr\u00e9; Barbraud, Christophe; Porter-Smith, Rick; Jonsen, Ian; Resinger, Ryan; Pinaud, David; Tamura, Takeshi; Fraser, Alexander; Labrousse, Sara; Ropert-Coudert, Yan; Kirkwood, Roger; Wienecke, Barbara; Sumner, Michael; Jenouvrier, Stephanie; Ji, Rubao", "repository": "USAP-DC", "science_program": null, "title": "Dynamic fine-scale sea-icescape shapes adult emperor penguin foraging habitat in East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601209"}], "date_created": "Wed, 07 Aug 2019 00:00:00 GMT", "description": "During winter, sea-ice coverage along the Antarctic coast is punctuated by numerous polynyas--isolated openings of tens to hundreds of kilometer wide. These coastal polynyas are hotspots of sea ice production and the primary source regions of the bottom water in the global ocean. They also host high levels of biological activities and are the feeding grounds of Emperor penguins and marine mammals. The polynyas are a key component of the Antarctic coastal system and crucial for the survival of penguins and many other species. These features also differ dramatically from each other in timing of formation, duration, phytoplankton growth season, and overall biological productivity. Yet, the underlying reasons for differences among them are largely unknown. This project studies the fundamental biophysical processes at a variety of polynyas, examines the connection between the physical environment and the phytoplankton and penguin ecology, and investigates the mechanisms behind polynya variability. The results of this interdisciplinary study will provide a context for interpretation of field measurements in Antarctic coastal polynyas, set a baseline for future polynya studies, and examine how polynya ecosystems may respond to local and large-scale environmental changes. The project will include educational and outreach activities that convey scientific messages to a broad audience. It aims to increase public awareness of the interconnection between large-scale environmental change and Antarctic coastal systems. The main objectives of this study are to form a comprehensive understanding of the temporal and spatial variability of Antarctic coastal polynyas and the physical controls of polynya ecosystems. The project takes an interdisciplinary approach and seeks to establish a modeling system centered on the Regional Ocean Modeling System. This system links the ice and ocean conditions to the plankton ecology and penguin population. Applications of the modeling system in representative polynyas, in conjunction with analysis of existing observations, will determine the biophysical influences of individual forcing factors. In particular, this study will test a set of hypothesized effects of winds, offshore water intrusion, ice-shelf melting, sea-ice formation, glacier tongues, and ocean stratification on the timing of polynya phytoplankton bloom and the overall polynya biological productivity. The project will also examine how changing polynya state affects penguin breeding success, adult survival, and population growth. The team will conduct idealized sensitivity analysis to explore implications of forcing variability, including local and large-scale environmental change, on Antarctic coastal ecosystems.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; Animal Behavior; Penguin; FIELD INVESTIGATION; USAP-DC; COASTAL; PENGUINS; SEA ICE; Antarctica; OCEAN MIXED LAYER", "locations": "Southern Ocean; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Zhang, Weifeng; Ji, Rubao; Jenouvrier, Stephanie; Maksym, Edward; Li, Yun", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Polynyas in Coastal Antarctica (PICA): Linking Physical Dynamics to Biological Variability", "uid": "p0010044", "west": -180.0}, {"awards": "1542791 Salas, Leonardo; 1543230 Ainley, David; 1543003 Stammerjohn, Sharon; 1543311 LaRue, Michelle", "bounds_geometry": "POLYGON((-180 -64,-144 -64,-108 -64,-72 -64,-36 -64,0 -64,36 -64,72 -64,108 -64,144 -64,180 -64,180 -65.4,180 -66.8,180 -68.2,180 -69.6,180 -71,180 -72.4,180 -73.8,180 -75.2,180 -76.6,180 -78,144 -78,108 -78,72 -78,36 -78,0 -78,-36 -78,-72 -78,-108 -78,-144 -78,-180 -78,-180 -76.6,-180 -75.2,-180 -73.8,-180 -72.4,-180 -71,-180 -69.6,-180 -68.2,-180 -66.8,-180 -65.4,-180 -64))", "dataset_titles": "ContinentalWESEestimates; Counting seals from space tutorial; Fast Ice Tool; Weddell seals habitat suitability model for the Ross Sea", "datasets": [{"dataset_uid": "200046", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Weddell seals habitat suitability model for the Ross Sea", "url": "https://github.com/leosalas/WeddellSeal_SOS"}, {"dataset_uid": "200047", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Counting seals from space tutorial", "url": "https://www.int-res.com/articles/suppl/m612p193_supp.pdf"}, {"dataset_uid": "200045", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Fast Ice Tool", "url": "https://github.com/leosalas/FastIceCovars"}, {"dataset_uid": "200234", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "ContinentalWESEestimates", "url": "https://github.com/leosalas/ContinentalWESEestimates"}], "date_created": "Fri, 02 Aug 2019 00:00:00 GMT", "description": "The Weddell seal is the southern-most mammal in the world, having a circumpolar distribution around Antarctica; the McMurdo Sound population in Antarctica is one of the best-studied mammal populations on earth. However, despite this, an understanding of how populations around the continent will fare under climate change is poorly understood. A complicating matter is the potential effects of a commercial enterprise in the Antarctic: a fishery targeting toothfish, which are important prey for Weddell seals. Although the species is easily detected and counted during the breeding season, no reliable estimates of continent-wide Weddell seal numbers exist, due to the logistic difficulties of surveying vast regions of Antarctica. Large-scale estimates are needed to understand how seal populations are responding to the fishery and climate change, because these drivers of change operate at scales larger than any single population, and may affect seals differently in different regions of the continent. We will take advantage of the ease of detectability of darkly colored seals when they the on ice to develop estimates of abundance from satellite images. This project will generate baseline data on the global distribution and abundance of Weddell seals around the Antarctic and will link environmental variables to population changes to better understand how the species will fare as their sea ice habitat continues to change. These results will help disentangle the effects of climate change and fishery operations, results that are necessary for appropriate international policy regarding fishery catch limits, impacts on the environment, and the value of marine protected areas. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. It will engage \"arm-chair\" scientists of all ages through connections with several non-governmental organizations and the general public. Anyone with access to the internet, including people who are physically unable to participate in field research directly, can participate in this project while simultaneously learning about multiple aspects of polar ecology through the project\u0027s interactive website. Specifically, this research project will: 1) Quantify the distribution of Weddell seals around Antarctica and 2) Determine the impact of environmental variables (such as fast ice extent, ocean productivity, bathymetry) on habitat suitability and occupancy. To do this, the project will crowd-source counting of seals on high-resolution satellite images via a commercial citizen science platform. Variation in seal around the continent will then be related to habitat variables through generalized linear models. Specific variables, such as fast ice extent will be tested to determine their influence on population variability through both space and time. The project includes a rigorous plan for ensuring quality control in the dataset including ground truth data from other, localized projects concurrently funded by the National Science Foundation\u0027s Antarctic Science Program.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "COASTAL; Southern Ocean; COMMUNITY DYNAMICS; MAMMALS; SEA ICE; NOT APPLICABLE; Antarctica; PENGUINS; USAP-DC", "locations": "Antarctica; Southern Ocean", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "LaRue, Michelle; Stamatiou, Kostas", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "GitHub", "repositories": "GitHub; Publication", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Determining Factors Affecting Distribution and Population Variability of the Ice-obligate Weddell Seal", "uid": "p0010041", "west": -180.0}, {"awards": "1543267 Brook, Edward J.; 1543229 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Multi-site ice core Krypton stable isotope ratios; Noble Gas Data from recent ice in Antarctica for 86Kr problem", "datasets": [{"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Etheridge, David; Mosley-Thompson, Ellen; Mulvaney, Robert; Buizert, Christo; Shackleton, Sarah; Severinghaus, Jeffrey P.; Pyne, Rebecca L.; Bertler, Nancy; Brook, Edward J.; Baggenstos, Daniel; Bereiter, Bernhard", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Etheridge, David; Brook, Edward J.; Pyne, Rebecca L.; Bereiter, Bernhard; Baggenstos, Daniel; Buizert, Christo; Mulvaney, Robert; Mosley-Thompson, Ellen; Severinghaus, Jeffrey P.; Bertler, Nancy; Shackleton, Sarah", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601394", "doi": "10.15784/601394", "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "people": "Shackleton, Sarah; Brook, Edward J.; Severinghaus, Jeffrey P.; Pyne, Rebecca L.; Mosley-Thompson, Ellen; Bertler, Nancy; Buizert, Christo; Mulvaney, Robert; Etheridge, David; Baggenstos, Daniel; Bereiter, Bernhard", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Multi-site ice core Krypton stable isotope ratios", "url": "https://www.usap-dc.org/view/dataset/601394"}, {"dataset_uid": "601195", "doi": "10.15784/601195", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Krypton; Noble Gas; Xenon", "people": "Shackleton, Sarah; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Noble Gas Data from recent ice in Antarctica for 86Kr problem", "url": "https://www.usap-dc.org/view/dataset/601195"}], "date_created": "Wed, 10 Jul 2019 00:00:00 GMT", "description": "Brook 1543267 Approximately half of the human caused carbon dioxide emissions to the atmosphere are absorbed by the ocean, which reduces the amount of global warming associated with these emissions. Much of this carbon uptake occurs in the Southern Ocean around Antarctica, where water from the deep ocean comes to the surface. How much water \"up-wells,\" and therefore how much carbon is absorbed, is believed to depend on the strength and location of the major westerly winds in the southern hemisphere. These wind patterns have been shifting southward in recent decades, and future changes could impact the global carbon cycle and promote the circulation of relatively warm water from the deep ocean on to the continental shelf, which contributes to enhanced Antarctic ice melt and sea level rise. Understanding of the westerly winds and their role in controlling atmospheric carbon dioxide levels and the circulation of ocean water is therefore very important. The work supported by this award will study past movement of the SH westerlies in response to natural climate variations. Of particular interest is the last deglaciation (20,000 to 10,000 years ago), when the global climate made a transition from an ice age climate to the current warm period. During this period, atmospheric carbon dioxide rose from about 180 ppm to 270 parts per million, and one leading hypothesis is that the rise in carbon dioxide was driven by a southward movement of the southern hemisphere westerlies. The broader impacts of the work include a perspective on past movement of the southern hemisphere westerlies and their link to atmospheric carbon dioxide, which could guide projections of future oceanic carbon dioxide uptake, with strong societal benefits; international collaboration with German scientists; training of a postdoctoral investigator; and outreach to public schools. This project will investigate whether the abundance of a noble gas, krypton-86, trapped in Antarctic ice cores, records atmospheric pressure variability, and whether or not this pressure variability can be used to infer past movement of the Southern Hemisphere westerly winds. The rationale for the project is that models of air movement in the snow pack (firn) in Antarctica indicate that pressure variations drive air movement that disturbs the normal enrichment in krypton-86 caused by gravitational settling of gases. Calculations predict that the krypton-86 deviation from gravitational equilibrium reflects the magnitude of pressure variations. In turn, atmospheric data show that pressure variability over Antarctica is linked to the position of the southern hemisphere westerly winds. Preliminary data from the West Antarctic Ice Sheet (WAIS) Divide ice core show a large excursion in krypton-86 during the transition from the last ice age to the current warm period. The investigators will perform krypton-86 analysis on ice core and firn air samples to establish whether the Kr-86 deviation is linked to pressure variability, refine the record of krypton isotopes from the WAIS Divide ice core, investigate the role of pressure variability in firn air transport using firn air models, and investigate how barometric pressure variability in Antarctica is linked to the position/strength of the SH westerlies in past and present climates.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USA/NSF; FIRN; ICE CORE RECORDS; USAP-DC; Greenland; Xenon; Noble Gas; Ice Core; Amd/Us; Antarctica; AMD; LABORATORY; Krypton; ATMOSPHERIC PRESSURE", "locations": "Greenland; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Brook, Edward J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation", "uid": "p0010037", "west": -180.0}, {"awards": "1758224 Salvatore, Mark", "bounds_geometry": "POLYGON((-180 -83,-178 -83,-176 -83,-174 -83,-172 -83,-170 -83,-168 -83,-166 -83,-164 -83,-162 -83,-160 -83,-160 -83.4,-160 -83.8,-160 -84.2,-160 -84.6,-160 -85,-160 -85.4,-160 -85.8,-160 -86.2,-160 -86.6,-160 -87,-162 -87,-164 -87,-166 -87,-168 -87,-170 -87,-172 -87,-174 -87,-176 -87,-178 -87,180 -87,178 -87,176 -87,174 -87,172 -87,170 -87,168 -87,166 -87,164 -87,162 -87,160 -87,160 -86.6,160 -86.2,160 -85.8,160 -85.4,160 -85,160 -84.6,160 -84.2,160 -83.8,160 -83.4,160 -83,162 -83,164 -83,166 -83,168 -83,170 -83,172 -83,174 -83,176 -83,178 -83,-180 -83))", "dataset_titles": "Laboratory Hyperspectral Reflectance Data of Central Transantarctic Mountain Rocks and Sediments; Orbital imagery used for SpecMap project", "datasets": [{"dataset_uid": "601163", "doi": "10.15784/601163", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Remote Sensing; Rocks; Solid Earth; Spectroscopy; Transantarctic Mountains", "people": "Salvatore, Mark", "repository": "USAP-DC", "science_program": null, "title": "Laboratory Hyperspectral Reflectance Data of Central Transantarctic Mountain Rocks and Sediments", "url": "https://www.usap-dc.org/view/dataset/601163"}, {"dataset_uid": "002735", "doi": null, "keywords": null, "people": null, "repository": "PGC", "science_program": null, "title": "Orbital imagery used for SpecMap project", "url": "https://www.pgc.umn.edu/projects/specmap/"}], "date_created": "Thu, 14 Mar 2019 00:00:00 GMT", "description": "Intellectual Merit: Ice free rock outcrops in the Transantarctic Mountains provide the only accessible windows into the interior of the ice covered Antarctic continent; they are extremely remote and difficult to study. This region also hosts the highest latitude ice-free valley systems on the planet. Based on two interdisciplinary workshops, the Transantarctic region near the Shackleton Glacier has been identified as a high priority site for further studies, with a field camp proposed for the 2015-2016 Antarctic field season. The geology of this region has been studied since the heroic era of Antarctic exploration, in the early 1900s, but geologic mapping has not been updated in more than forty years, and existing maps are at poor resolution (typically 1:250,000). This project would utilize the WorldView-2 multispectral orbital dataset to supplement original geologic mapping efforts near the proposed 2015-2016 Shackleton Glacier camp. The WorldView-2 satellite is the only multispectral orbiting sensor capable of imaging the entirety of the Transantarctic Mountains, and all necessary data are currently available to the Polar Geospatial Center. High-latitude atmospheric correction of multispectral data for geologic investigations has only recently been tested, but has never been applied to WorldView-2 data, and never for observations of this type. Therefore, this research will require technique refinements and methodological developements to accomplish the goals. Atmospheric correction refinements and spectral validation will be made possible by laboratory spectroscopic measurements of rock samples currently stored at the U.S. Polar Rock Repository, at the Ohio State University. This project will result in spectral unit identification and boundary mapping at a factor of four higher resolution (1:62,500) than previous geologic mapping efforts, and more detailed investigations (1:5,123) are possible at resolutions more than a factor of forty-eight improved over previous geologic maps. Validated spectral mapping at these improved resolutions will allow for detailed lithologic, and potentially biologic, mapping using existing satellite imagery. This will greatly enhance planning capabilities, thus maximizing the efficiency of the scientific research and support logistics associated with the Shackleton Glacier deep field camp. Broader impacts: The proposed work will have multiple impacts on the broader scientific community. First, the refinement of existing atmospheric correction methodologies, and the development of new spectral mapping techniques, may substantially improve our ability to remotely investigate geologic surfaces throughout Antarctica. The ability to validate this orbital dataset will be of use to both current and future geologic, environmental, and biologic studies, potentially across the entire continent. The project will yield a specific spectral mapping product (at a scale of 1:62,500) to the scientific community by a targeted date of 01 March 2014, in order to support proposals submitted to the National Science Foundation for the proposed 2015/2016 Shackleton Glacier camp. High-resolution spectral mapping products (up to a maximum resolution of 2 meters per pixel) will also be generated for regions of particular scientific interest. The use of community based resources, such as Polar Geospatial Center (PGC) imagery and U.S. Polar Rock Repository rock samples, will generate new synergistic and collaborative research possibilities within the Antarctic research community. In addition, the lead PI (Salvatore) is an early career scientist who is active in both Antarctic and planetary remote sensing. There are overlaps in the calibration, correction, and validation of remote spectral datasets for Antarctic and planetary applications which can lead to benefits and insights to an early career PI, as well as the two communities.", "east": -160.0, "geometry": "POINT(180 -85)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Antarctica; GEOCHEMISTRY; LANDSCAPE; REFLECTED INFRARED; USAP-DC", "locations": "Antarctica", "north": -83.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Salvatore, Mark", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "PGC; USAP-DC", "science_programs": null, "south": -87.0, "title": "EAGER: Surface Variability and Spectral Analyses of the Central Transantarctic Mountains, Antarctica", "uid": "p0010020", "west": 160.0}, {"awards": "1644245 Aydin, Murat", "bounds_geometry": null, "dataset_titles": "Ice Core Air Ethane and Acetylene Measurements - South Pole SPC14 Ice Core (SPICEcore project); Ice core ethane measurements, Greenland and Antarctica, 1000-1900 CE.", "datasets": [{"dataset_uid": "002574", "doi": "", "keywords": null, "people": null, "repository": "Arctic Data Center", "science_program": null, "title": "Ice core ethane measurements, Greenland and Antarctica, 1000-1900 CE.", "url": "https://arcticdata.io/catalog/view/doi:10.18739/A2CR5NC1B"}, {"dataset_uid": "601367", "doi": "10.15784/601367", "keywords": "Antarctica; Ethane", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Ice Core Air Ethane and Acetylene Measurements - South Pole SPC14 Ice Core (SPICEcore project)", "url": "https://www.usap-dc.org/view/dataset/601367"}], "date_created": "Tue, 13 Nov 2018 00:00:00 GMT", "description": "Aydin/1644245 This award supports a project to measure ethane in ice core air extracted from the recently drilled intermediate depth South Pole ice core (SPICECORE). Ethane is an abundant hydrocarbon in the atmosphere. The ice core samples that will be used in this analysis will span about 150 years before present to about 55,000 years before present and therefore, ethane emissions linked to human activities are not a subject of this study. The study will focus on quantifying the variability in the natural sources of ethane and the processes that govern its removal from the atmosphere. A long-term ice core ethane record will provide new knowledge on the chemistry of Earth?s atmosphere during time periods when human influence was either much smaller than present day or non-existent. The broader impacts of this work include education and training of students and a contribution to a better understanding of the chemistry of the atmosphere in the past and how it has been impacted by past changes in climate. Natural sources that emit ethane are both geologic (e.g. seeps, vents, mud volcanoes etc.) and pyrogenic (wild fires) which is commonly called biomass burning. Ethane is removed from the atmosphere via oxidation reactions. The ice core ethane measurements have great potential as a proxy for gaseous emissions from biomass burning. This is especially true for time periods preceding the industrial revolution when atmospheric variability of trace gases was largely controlled by natural processes. Another objective of this study is to improve understanding of the causes of atmospheric methane variability apparent which are in the existing ice core records. Methane is a simpler hydrocarbon than ethane and more abundant in the atmosphere. Even though the project does not include any methane measurements; the commonalities between the sources and removal of atmospheric ethane and methane mean that ethane measurements can be used to gain insight into the causes of changes in atmospheric methane levels. The broader impacts of the project include partial support for one Ph.D. student and support for undergraduate researchers at UC Irvine. The PIs group currently has 4 undergraduate researchers. The PI and the graduate students in the UCI ice core laboratory regularly participate in on- and off-campus activities such as laboratory tours and lectures directed towards educating high-school students and science teachers, and the local community at large about the scientific value of polar ice cores as an environmental record of our planet\u0027s past. The results of this research will be disseminated via peer-review publications and will contribute to policy-relevant activities such as the IPCC Climate Assessment. Data resulting from this project will be archived in a national data repository. This award does not have field work in Antarctica.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "Arctic Data Center", "repositories": "Arctic Data Center; USAP-DC", "science_programs": "SPICEcore", "south": null, "title": "Ethane Measurements in the Intermediate Depth South Pole Ice Core (SPICECORE)", "uid": "p0000762", "west": null}, {"awards": "0838947 Tulaczyk, Slawek; 0838764 Anandakrishnan, Sridhar; 0838763 Anandakrishnan, Sridhar; 0838855 Jacobel, Robert; 0839142 Tulaczyk, Slawek; 0839107 Powell, Ross; 0839059 Powell, Ross", "bounds_geometry": null, "dataset_titles": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line; Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD); Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES); IRIS ID#s 201035, 201162, 201205; IRIS offers free and open access to a comprehensive data store of raw geophysical time-series data collected from a large variety of sensors, courtesy of a vast array of US and International scientific networks, including seismometers (permanent and temporary), tilt and strain meters, infrasound, temperature, atmospheric pressure and gravimeters, to support basic research aimed at imaging the Earth\u0027s interior.; Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set; Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set; Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone; The IRIS DMC archives and distributes data to support the seismological research community.; UNAVCO ID#s WHL1, WHL2, LA02, LA09 (full data link not provided)", "datasets": [{"dataset_uid": "609594", "doi": "10.7265/N54J0C2W", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS; Radar; Whillans Ice Stream", "people": "Jacobel, Robert", "repository": "USAP-DC", "science_program": null, "title": "Radar Studies of Subglacial Lake Whillans and the Whillans Ice Stream Grounding Zone", "url": "https://www.usap-dc.org/view/dataset/609594"}, {"dataset_uid": "001406", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "The IRIS DMC archives and distributes data to support the seismological research community.", "url": "http://ds.iris.edu/ds/nodes/dmc/"}, {"dataset_uid": "001405", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS offers free and open access to a comprehensive data store of raw geophysical time-series data collected from a large variety of sensors, courtesy of a vast array of US and International scientific networks, including seismometers (permanent and temporary), tilt and strain meters, infrasound, temperature, atmospheric pressure and gravimeters, to support basic research aimed at imaging the Earth\u0027s interior.", "url": "http://www.iris.edu/hq/data_and_software"}, {"dataset_uid": "601234", "doi": "10.15784/601234", "keywords": "ACL; Antarctica; Biomarker; BIT Index; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Stream; Whillans Ice Stream; WISSARD", "people": "Askin, Rosemary; Baudoin, Patrick; Warny, Sophie; Scherer, Reed Paul; Coenen, Jason; Casta\u00f1eda, Isla", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Biomarker Data Set", "url": "https://www.usap-dc.org/view/dataset/601234"}, {"dataset_uid": "601245", "doi": "10.15784/601245", "keywords": "Antarctica; Pollen; West Antarctica; WISSARD", "people": "Coenen, Jason; Scherer, Reed Paul; Askin, Rosemary; Warny, Sophie; Baudoin, Patrick; Casta\u00f1eda, Isla", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Paleogene marine and terrestrial development of the West Antarctic Rift System: Palynomorph Data Set", "url": "https://www.usap-dc.org/view/dataset/601245"}, {"dataset_uid": "601122", "doi": "10.15784/601122", "keywords": "Antarctica; Flexure Zone; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Ice-Shelf Basal Melting; Ice-Shelf Strain Rate", "people": "Begeman, Carolyn", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Basal melt rates of the Ross Ice Shelf near the Whillans Ice Stream grounding line", "url": "https://www.usap-dc.org/view/dataset/601122"}, {"dataset_uid": "600155", "doi": "10.15784/600155", "keywords": "Antarctica; Glaciology; Oceans; Southern Ocean; WISSARD", "people": "Powell, Ross", "repository": "USAP-DC", "science_program": null, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats - Robotic Access to Grounding-zones for Exploration and Science (RAGES)", "url": "https://www.usap-dc.org/view/dataset/600155"}, {"dataset_uid": "600154", "doi": "10.15784/600154", "keywords": "Antarctica; Biota; Diatom; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Lake Whillans; Paleoclimate; Ross Sea; Southern Ocean; Subglacial Lake; WISSARD", "people": "Powell, Ross", "repository": "USAP-DC", "science_program": null, "title": "Integrative Study of Marine Ice Sheet Stability and Subglacial Life Habitats in W Antarctica - Lake and Ice Stream Subglacial Access Research Drilling (LISSARD)", "url": "https://www.usap-dc.org/view/dataset/600154"}, {"dataset_uid": "000150", "doi": "", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "UNAVCO ID#s WHL1, WHL2, LA02, LA09 (full data link not provided)", "url": "http://www.unavco.org/"}, {"dataset_uid": "000148", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS ID#s 201035, 201162, 201205", "url": "http://ds.iris.edu/"}], "date_created": "Mon, 10 Sep 2018 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF\u0027s Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling. \u003cbr/\u003e\u003cbr/\u003eINTELLECTUAL MERIT: The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. \u003cbr/\u003e\u003cbr/\u003eBROADER IMPACTS: Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": true, "keywords": "USAP-DC; Ice Penetrating Radar; Antarctic; Subglacial Lake; Subglacial Hydrology; Grounding Line; Sea Level Rise; Bed Reflectivity; Ice Sheet Stability; Stability; Radar; Sub-Ice-Shelf; Geophysics; Biogeochemical; LABORATORY; Sediment; Sea Floor Sediment; Ice Thickness; Model; Ice Stream Stability; Basal Ice; SATELLITES; Ice Sheet Thickness; Subglacial; Antarctica; NOT APPLICABLE; Antarctic Ice Sheet; Ice Sheet; FIELD SURVEYS; Surface Elevation; Geochemistry; FIELD INVESTIGATION; Not provided", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Fisher, Andrew; Powell, Ross; Anandakrishnan, Sridhar; Jacobel, Robert; Scherer, Reed Paul", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repo": "USAP-DC", "repositories": "IRIS; UNAVCO; USAP-DC", "science_programs": "WISSARD", "south": null, "title": "Collaborative Research: Integrative Study of Marine Ice Sheet Stability \u0026 Subglacial Life Habitats in W Antarctica - Lake \u0026 Ice Stream Subglacial Access Research Drilling (LISSARD)", "uid": "p0000105", "west": null}, {"awards": "1141889 Winberry, J. Paul; 1141866 Conway, Howard", "bounds_geometry": null, "dataset_titles": "Beardmore Glacier High-Frequency Impulse Radar Data; Geophysical measurements Beardmore Glacier, Antarctica; Project code ZF for passive seismic and 17-030 for active source", "datasets": [{"dataset_uid": "601713", "doi": "10.15784/601713", "keywords": "Antarctica; Beardmore Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Christianson, Knut; Conway, Howard; Hoffman, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Beardmore Glacier High-Frequency Impulse Radar Data", "url": "https://www.usap-dc.org/view/dataset/601713"}, {"dataset_uid": "000210", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Project code ZF for passive seismic and 17-030 for active source", "url": "https://ds.iris.edu/mda/17-030"}, {"dataset_uid": "601121", "doi": "10.15784/601121", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Radar", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Geophysical measurements Beardmore Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601121"}], "date_created": "Sun, 09 Sep 2018 00:00:00 GMT", "description": "Conway/1141866 This award supports a project to conduct a suite of experiments to study spatial and temporal variations of basal conditions beneath Beardmore Glacier, an East Antarctic outlet glacier that discharges into the Ross Sea Embayment. The intellectual merit of the project is that it should help verify whether or not global warming will play a much larger role in the future mass balance of ice sheets than previously considered. Recent observations of rapid changes in discharge of fast-flowing outlet glaciers and ice streams suggest that dynamical responses to warming could affect that ice sheets of Greenland and Antarctica. Assessment of possible consequences of these responses is hampered by the lack of information about the basal boundary conditions. The leading hypothesis is that variations in basal conditions exert strong control on the discharge of outlet glaciers. Airborne and surface-based radar measurements of Beardmore Glacier will be made to map the ice thickness and geometry of the sub-glacial trough and active and passive seismic experiments, together with ground-based radar and GPS measurements will be made to map spatial and temporal variations of conditions at the ice-bed interface. The observational data will be used to constrain dynamic models of glacier flow. The models will be used to address the primary controls on the dynamics of Antarctic outlet glaciers, the conditions at the bed, their spatial and temporal variation, and how such variability might affect the sliding and flow of these glaciers. The work will also explore whether or not these outlet glaciers could draw down the interior of East Antarctica, and if so, how fast. The study will take three years including two field seasons to complete and results from the work will be disseminated through public and professional meetings and journal publications. All data and metadata will be made available through the NSIDC web portal. The broader impacts of the work are that it will help elucidate the fundamental physics of outlet glacier dynamics which is needed to improve predictions of the response of ice sheets to changing environmental conditions. The project will also provide support for early career investigators and will provide training and support for one graduate and two undergraduate students. All collaborators are currently involved in scientific outreach and graduate student education and they are committed to fostering diversity.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard; Winberry, Paul", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "IRIS; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: East Antarctic Outlet Glacier Dynamics", "uid": "p0000437", "west": null}, {"awards": "1341311 Timmermann, Axel", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "784 ka transient Antarctic ice-sheet model simulation data", "datasets": [{"dataset_uid": "000247", "doi": "", "keywords": null, "people": null, "repository": "IBS Center for Climate Physics ICCP", "science_program": null, "title": "784 ka transient Antarctic ice-sheet model simulation data", "url": "http://climatedata.ibs.re.kr/grav/data/psu-love/antarctic-ice-sheet"}], "date_created": "Tue, 26 Jun 2018 00:00:00 GMT", "description": "Timmerman/1341311 This award supports a project to study the physical processes that synchronize glacial-scale variability between the Northern Hemisphere ice sheets and the Antarctic ice-sheet. Using a coupled numerical ice-sheet earth-system model, the research team will explore the cryospheric responses to past changes in greenhouse gas concentrations and variations in earth\u0027s orbit and tilt. First capturing the sensitivity of each individual ice-sheet to these forcings and then determining their joint variability induced by changes in sea level, ocean temperatures and atmospheric circulation, the researchers will quantify the relative roles of local versus remote effects on long-term ice volume variability. The numerical experiments will provide deeper physical insights into the underlying dynamics of past Antarctic ice-volume changes and their contribution to global sea level. Output from the transient earth system model simulations will be directly compared with ice-core data from previous and ongoing drilling efforts, such as West Antarctic Ice Sheet (WAIS) Divide. Specific questions that will be addressed include: 1) Did the high-latitude Southern Hemispheric atmospheric and oceanic climate, relevant to Antarctic ice sheet forcing, respond to local insolation variations, CO2, Northern Hemispheric changes, or a combination thereof?; 2) How did WAIS and East Antarctic Ice Sheet (EAIS) vary through the Last Glacial Termination and into the Holocene (21 ka- present)?; 3) Did the WAIS (or EAIS) contribute to rapid sea-level fluctuations during this period, such as Meltwater Pulse 1A? 4) Did WAIS collapse fully at Stage 5e (~ 125 ka), and what was its timing relative to the maximum Greenland retreat?; and 5) How did the synchronized behavior of Northern Hemisphere and Southern Hemisphere ice-sheet variations affect the strength of North Atlantic Deep Water and Antarctic Bottom Water formation and the respective overturning cells? The transient earth-system model simulations conducted as part of this project will be closely compared with paleo-climate reconstructions from ice cores, sediment cores and terrestrial data. This will generate an integrated understanding of the hemispheric contributions of deglacial climate change, the origin of meltwater pulses, and potential thresholds in the coupled ice-sheet climate system in response to different types of forcings. A well-informed long-term societal response to sea level rise requires a detailed understanding of ice-sheet sensitivities to external forcing. The proposed research will strongly contribute to this task through numerical modeling and paleo-data analysis. The research team will make the resulting model simulations available on the web-based data server at the Asia Pacific Data Research Center (APDRC) to enable further analysis by the scientific community. As part of this project a female graduate student and a postdoctoral researcher will receive training in earth-system and ice-sheet modeling and paleo-climate dynamics. This award has no field work in Antarctica.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Timmermann, Axel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "IBS Center for Climate Physics ICCP", "repositories": "IBS Center for Climate Physics ICCP", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Bipolar Coupling of late Quaternary Ice Sheet Variability", "uid": "p0000379", "west": -180.0}, {"awards": "1443341 Hawley, Robert; 1443471 Koutnik, Michelle", "bounds_geometry": "POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))", "dataset_titles": "7MHz radar in the vicinity of South Pole; Firn density and compaction rates 50km upstream of South Pole; Firn temperatures 50km upstream of South Pole; Shallow radar near South Pole; South Pole area GPS velocities; SPICEcore Advection", "datasets": [{"dataset_uid": "601266", "doi": "10.15784/601266", "keywords": "Antarctica; Ice Core Data; South Pole; SPICEcore", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore Advection", "url": "https://www.usap-dc.org/view/dataset/601266"}, {"dataset_uid": "601100", "doi": "10.15784/601100", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Velocity", "people": "Conway, Howard; Koutnik, Michelle; Fudge, T. J.; Lilien, David; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole area GPS velocities", "url": "https://www.usap-dc.org/view/dataset/601100"}, {"dataset_uid": "601369", "doi": "10.15784/601369", "keywords": "Antarctica; Ice Sheet", "people": "Koutnik, Michelle; Conway, Howard; Fudge, T. J.; Lilien, David; Stevens, Max; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "7MHz radar in the vicinity of South Pole", "url": "https://www.usap-dc.org/view/dataset/601369"}, {"dataset_uid": "601525", "doi": "10.15784/601525", "keywords": "Antarctica; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Snow/ice; Snow/Ice; South Pole; SPICEcore; Temperature", "people": "Lilien, David; Koutnik, Michelle; Conway, Howard; Fudge, T. J.; Waddington, Edwin D.; Stevens, Christopher Max", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Firn temperatures 50km upstream of South Pole", "url": "https://www.usap-dc.org/view/dataset/601525"}, {"dataset_uid": "601099", "doi": "10.15784/601099", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; Snow Accumulation; Snow/ice; Snow/Ice", "people": "Lilien, David; Waddington, Edwin D.; Conway, Howard; Koutnik, Michelle; Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Shallow radar near South Pole", "url": "https://www.usap-dc.org/view/dataset/601099"}, {"dataset_uid": "601680", "doi": "10.15784/601680", "keywords": "Antarctica; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Snow/ice; Snow/Ice; South Pole; Temperature", "people": "Conway, Howard; Stevens, Christopher Max; Lilien, David; Waddington, Edwin D.; Koutnik, Michelle; Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Firn density and compaction rates 50km upstream of South Pole", "url": "https://www.usap-dc.org/view/dataset/601680"}], "date_created": "Thu, 14 Jun 2018 00:00:00 GMT", "description": "Ice-core records are critical to understanding past climate variations. An Antarctic ice core currently being drilled at the South Pole will allow detailed investigation of atmospheric gases and fill an important gap in understanding the pattern of climate variability across Antarctica. Critical to the interpretation of any ice core are: 1) accurate chronologies for both the ice and the trapped gas and 2) demonstration that records from the ice core reliably reflect climate. The proposed research will improve the ice and gas chronologies by making measurements of snow compaction in the upstream catchment in order to constrain age models of the ice. These measurements will be a key data set needed for better understanding and predicting time-varying conditions in the upper part of the ice sheet. The research team will measure the modern spatial gradients in accumulation rate, surface temperature, and water stable isotopes from shallow ice cores in the upstream catchment in order to determine the climate history from the ice-core record. The new ice-flow measurements will make it possible to define the path of ice from upstream to the South Pole ice-core drill site to assess spatial gradients in snowfall and to infer histories of snowfall from internal layers within the ice sheet. The project will be led by an early-career scientist, provide broad training to graduate students, and engage in public outreach on polar science. Ice-core records of stable isotopes, aerosol-born particles, and atmospheric gases are critical to understanding past climate variations. The proposed research will improve the ice and gas chronologies in the South Pole ice core by making in situ measurements of firn compaction in the upstream catchment to constrain models of the gas-age ice-age difference. The firn measurements will be a key data set needed to form a constitutive relationship for firn, and will drive better understanding and prediction of transient firn evolution. The research team will measure the modern gradients in accumulation rate, surface temperature, and water stable isotopes in the upstream catchment to separate spatial (advection) variations from temporal (climate) variations in the ice-core records. The ice-flow measurements will define the flowline upstream of the drill site, assess spatial gradients in accumulation, and infer histories of accumulation from radar-observed internal layers. Results will directly enhance interpretation of South Pole ice-core records, and also advance understanding of firn densification and drive next-generation firn models.", "east": 180.0, "geometry": "POINT(145 -89.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIRN; Firn; USAP-DC; South Pole; Radar; FIELD SURVEYS; ICE CORE RECORDS", "locations": "South Pole", "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Conway, Howard; Waddington, Edwin D.; Fudge, T. J.; Hawley, Robert L.; Osterberg, Erich", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core", "uid": "p0000200", "west": 110.0}, {"awards": "1440435 Ducklow, Hugh; 2023425 Schofield, Oscar", "bounds_geometry": "POLYGON((-80 -63,-78.3 -63,-76.6 -63,-74.9 -63,-73.2 -63,-71.5 -63,-69.8 -63,-68.1 -63,-66.4 -63,-64.7 -63,-63 -63,-63 -63.8,-63 -64.6,-63 -65.4,-63 -66.2,-63 -67,-63 -67.8,-63 -68.6,-63 -69.4,-63 -70.2,-63 -71,-64.7 -71,-66.4 -71,-68.1 -71,-69.8 -71,-71.5 -71,-73.2 -71,-74.9 -71,-76.6 -71,-78.3 -71,-80 -71,-80 -70.2,-80 -69.4,-80 -68.6,-80 -67.8,-80 -67,-80 -66.2,-80 -65.4,-80 -64.6,-80 -63.8,-80 -63))", "dataset_titles": "Environmental Data Initiative Repository, Supporting LTER; Expedition Data; Expedition data of LMG1501; Expedition data of LMG1601; Expedition data of LMG1701; Expedition data of LMG1801; Expedition data of LMG1901; Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae); UAV images and video of whales in the Antarctic Penisula during LMG1802", "datasets": [{"dataset_uid": "001367", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1701"}, {"dataset_uid": "000246", "doi": "", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "Environmental Data Initiative Repository, Supporting LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=PAL"}, {"dataset_uid": "200124", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1801", "url": "https://www.rvdata.us/search/cruise/LMG1801"}, {"dataset_uid": "200125", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1901", "url": "https://www.rvdata.us/search/cruise/LMG1901"}, {"dataset_uid": "200122", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1501", "url": "https://www.rvdata.us/search/cruise/LMG1501"}, {"dataset_uid": "200123", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1601", "url": "https://www.rvdata.us/search/cruise/LMG1601"}, {"dataset_uid": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Desvignes, Thomas; Corso, Andrew; Hilton, Eric; Steinberg, Deborah; Biesack, Ellen; Cheng, Chi-Hing; McDowell, Jan", "repository": "USAP-DC", "science_program": "LTER", "title": "Metadata associated with the description of Akarotaxis gouldae n. sp. (Bathydraconidae)", "url": "https://www.usap-dc.org/view/dataset/601811"}, {"dataset_uid": "002729", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1701", "url": "https://www.rvdata.us/search/cruise/LMG1701"}, {"dataset_uid": "601318", "doi": "10.15784/601318", "keywords": "Aerial Imagery; Antarctica; Antarctic Peninsula; Biota; Camera; Humpback Whales; LMG1802; LTER; Minke Whales; Oceans; Palmer Station; Photo; Photo/video; Photo/Video; R/v Laurence M. Gould; Species Size; UAV; Video Data; Whales", "people": "Nowacek, Douglas; Boyer, Keyvi; Friedlaender, Ari; Dale, Julian; Bierlich, KC", "repository": "USAP-DC", "science_program": "LTER", "title": "UAV images and video of whales in the Antarctic Penisula during LMG1802", "url": "https://www.usap-dc.org/view/dataset/601318"}], "date_created": "Fri, 11 May 2018 00:00:00 GMT", "description": "The Palmer Antarctica LTER (Long Term Ecological Research) site has been in operation since 1990. The goal of all the LTER sites is to conduct policy-relevant research on ecological questions that require tens of years of data, and cover large geographical areas. For the Palmer Antarctica LTER, the questions are centered around how the marine ecosystem west of the Antarctica peninsula is responding to a climate that is changing as rapidly as any place on the Earth. For example, satellite observations over the past 35 years indicate the average duration of sea ice cover is now ~90 days (3 months!) shorter than it was. The extended period of open water has implications for many aspects of ecosystem research, with the concurrent decrease of Ad\u00e8lie penguins within this region regularly cited as an exemplar of climate change impacts in Antarctica. Cutting edge technologies such as autonomous underwater (and possibly airborne) vehicles, seafloor moorings, and numerical modeling, coupled with annual oceanographic cruises, and weekly environmental sampling, enables the Palmer Antarctica LTER to expand and bridge the time and space scales needed to assess climatic impacts. This award includes for the first time study of the roles of whales as major predators in the seasonal sea ice zone ecosystem. The team will also focus on submarine canyons, special regions of enhanced biological activity, along the Western Antarctic Peninsula (WAP). The current award\u0027s overarching research question is: How do seasonality, interannual variability, and long term trends in sea ice extent and duration influence the structure and dynamics of marine ecosystems and biogeochemical cycling? Specific foci within the broad question include: 1. Long-term change and ecosystem transitions. What is the sensitivity or resilience of the ecosystem to external perturbations as a function of the ecosystem state? 2. Lateral connectivity and vertical stratification. What are the effects of lateral transports of freshwater, heat and nutrients on local ocean stratification and productivity and how do they drive changes in the ecosystem? 3. Top-down controls and shifting baselines. How is the ecosystem responding to the cessation of whaling and subsequent long-term recovery of whale stocks? 4. Foodweb structure and biogeochemical processes. How do temporal and spatial variations in foodweb structure influence carbon and nutrient cycling, export, and storage? The broader impacts of the award leverage local educational partnerships including the Sandwich, MA STEM Academy, the New England Aquarium, and the NSF funded Polar Learning and Responding (PoLAR) Climate Change Education Partnership at Columbia\u0027s Earth Institute to build new synergies between Arctic and Antarctic, marine and terrestrial scientists and students, governments and NGOs. The Palmer Antarctic LTER will also conduct appropriate cross LTER site comparisons, and serve as a leader in information management to enable knowledge-building within and beyond the Antarctic, oceanographic, and LTER communities.", "east": -63.0, "geometry": "POINT(-71.5 -67)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "PELAGIC; USAP-DC; R/V LMG; NOT APPLICABLE; Palmer Station; LMG1701", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Ducklow, Hugh; Martinson, Doug; Schofield, Oscar", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "EDI; R2R; USAP-DC", "science_programs": "LTER", "south": -71.0, "title": "LTER Palmer, Antarctica (PAL): Land-Shelf-Ocean Connectivity, Ecosystem Resilience and Transformation in a Sea-Ice Influenced Pelagic Ecosystem", "uid": "p0000133", "west": -80.0}, {"awards": "1443232 Waddington, Edwin", "bounds_geometry": "POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))", "dataset_titles": "AC-ECM for SPICEcore; ECM (DC and AC) multi-track data and images from 2016 processing season", "datasets": [{"dataset_uid": "601189", "doi": " 10.15784/601189 ", "keywords": "Antarctica; Electrical Conductivity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Physical Properties; Snow/ice; Snow/Ice; South Pole; SPICEcore; Volcanic", "people": "Fudge, T. J.; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "AC-ECM for SPICEcore", "url": "https://www.usap-dc.org/view/dataset/601189"}, {"dataset_uid": "601366", "doi": "10.15784/601366", "keywords": "Antarctica", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "ECM (DC and AC) multi-track data and images from 2016 processing season", "url": "https://www.usap-dc.org/view/dataset/601366"}], "date_created": "Tue, 08 May 2018 00:00:00 GMT", "description": "Ice cores record detailed histories of past climate variations. The South Pole ice core will allow investigation of atmospheric trace gases and fill an important gap in understanding the pattern of climate variability across Antarctica. An accurate timescale that assigns an age to the ice at each depth in the core is essential to interpretation of the ice-core records. This work will use electrical methods to identify volcanic eruptions throughout the past ~40,000 years in the core by detecting the enhanced electrical conductance in those layers due to volcanic impurities in the ice. These eruptions will be pattern-matched to other cores across Antarctica, synchronizing the timing of climate variations among cores and allowing the precise timescales developed for other Antarctic ice cores to be transferred to the South Pole ice core. The well-dated records of volcanic forcing will be combined with records of atmospheric gases, stable water-isotopes, and aerosols to better understand the large natural climate variations of the past 40,000 years. The electrical conductance method and dielectric profiling measurements will be made along the length of each section of the South Pole ice core at the National Ice Core Lab. These measurements will help to establish a timescale for the core. Electrical measurements will provide a continuous record of volcanic events for the entire core including through the brittle ice (550-1250m representing ~10,000-20,000 year-old ice) where the core quality and thin annual layers may prevent continuous melt analysis and cause discrete measurements to miss volcanic events. The electrical measurements also produce a 2-D image of the electrical layering on a longitudinal cut surface of each core. These data will be used to identify any irregular or absent layering that would indicate a stratigraphic disturbance in the core. A robust chronology is essential to interpretation of the paleoclimate records from the South Pole ice core. The investigators will engage teachers through talks and webinars with the National Science Teachers Association and will share information with the public at events such as Polar Science Weekend at the Pacific Science Center. Results will be disseminated through publications and conference presentations and the data will be archived and publicly available.", "east": 180.0, "geometry": "POINT(145 -89.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; Amd/Us; AMD; LABORATORY", "locations": null, "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fudge, T. J.; Waddington, Edwin D.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Using Electrical Conductance Measurements to Develop the South Pole Ice Core Chronology", "uid": "p0000378", "west": 110.0}, {"awards": "0944021 Brook, Edward J.; 0944307 Conway, Howard; 0943466 Hawley, Robert", "bounds_geometry": "POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))", "dataset_titles": "Roosevelt Island Borehole Firn temperatures; Roosevelt Island Borehole Optical Televiewer logs; Roosevelt Island Ice Core Time Scale and Associated Data; Roosevelt Island: Radar and GPS", "datasets": [{"dataset_uid": "601085", "doi": "10.15784/601085", "keywords": "Antarctica; Borehole; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Records; Ice Fabric; Optical Images; Roosevelt Island; Snow/ice; Snow/Ice; Temperature", "people": "Giese, Alexandra; Hawley, Robert L.; Clemens-Sewall, David", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Borehole Firn temperatures", "url": "https://www.usap-dc.org/view/dataset/601085"}, {"dataset_uid": "601359", "doi": "10.15784/601359", "keywords": "Antarctica; CO2; Ice Core; Roosevelt Island", "people": "Brook, Edward J.; Lee, James", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Ice Core Time Scale and Associated Data", "url": "https://www.usap-dc.org/view/dataset/601359"}, {"dataset_uid": "601070", "doi": "10.15784/601070", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS Data; Ice Velocity; Navigation; Radar; Roosevelt Island; Ross Sea", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island: Radar and GPS", "url": "https://www.usap-dc.org/view/dataset/601070"}, {"dataset_uid": "601086", "doi": "10.15784/601086", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Roosevelt Island; Snow/ice; Snow/Ice", "people": "Clemens-Sewall, David; Hawley, Robert L.", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Borehole Optical Televiewer logs", "url": "https://www.usap-dc.org/view/dataset/601086"}], "date_created": "Fri, 16 Feb 2018 00:00:00 GMT", "description": "This award supports a project to use the Roosevelt Island ice core as a glaciological dipstick for the eastern Ross Sea. Recent attention has focused on the eastern Ross Embayment, where there are no geological constraints on ice thickness changes, due to the lack of protruding rock \"dipsticks\" where the ice sheet can leave datable records of high stands. Recent work has shown how dated ice cores can be used as dipsticks to derive ice-thickness histories. Partners from New Zealand and Denmark will extract an ice core from Roosevelt Island during the 2010-2011 and 2011-12 austral summers. Their science objective is to contribute to understanding of climate variability over the past 40kyr. The science goal of this project is not the climate record, but rather the history of deglaciation in the Ross Sea. The new history from the eastern Ross Sea will be combined with the glacial histories from the central Ross Sea (Siple Dome and Byrd) and existing and emerging histories from geologic and marine records along the western Ross Sea margin and will allow investigators to establish an updated, self-consistent model of the configuration and thickness of ice in the Ross Embayment during the LGM, and the timing of deglaciation. Results from this work will provide ground truth for new-generation ice-sheet models that incorporate ice streams and fast-flow dynamics. Realistic ice-sheet models are needed not only for predicting the response to future possible environments, but also for investigating past behaviors of ice sheets. This research contributes to the primary goals of the West Antarctic Ice Sheet Initiative as well as the IPY focus on ice-sheet history and dynamics. It also contributes to understanding spatial and temporal patterns of climate change and climate dynamics over the past 40kyr, one of the primary goals of the International Partnerships in Ice Core Sciences (IPICS). The project will help to develop the next generation of scientists and will contribute to the education and training of two Ph.D. students. All participants will benefit from the international collaboration, which will expose them to different field and laboratory techniques and benefit future collaborative work. All participants are involved in scientific outreach and undergraduate education, and are committed to fostering diversity. Outreach will be accomplished through regularly scheduled community and K-12 outreach events, talks and popular writing by the PIs, as well as through University press offices.", "east": -161.0, "geometry": "POINT(-162 -79.25)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "AMD; FIELD INVESTIGATION; Amd/Us; Deglaciation; USAP-DC; USA/NSF; NOT APPLICABLE; Ice Core; Not provided; Ross Sea Embayment", "locations": "Ross Sea Embayment", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Conway, Howard; Brook, Edward J.; Hawley, Robert L.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.5, "title": "Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island", "uid": "p0000272", "west": -163.0}, {"awards": "0732625 Leventer, Amy; 0732602 Truffer, Martin; 0732983 Vernet, Maria; 0732651 Gordon, Arnold; 0732655 Mosley-Thompson, Ellen; 0732711 Smith, Craig", "bounds_geometry": "POLYGON((-68 -57.8,-66.78 -57.8,-65.56 -57.8,-64.34 -57.8,-63.12 -57.8,-61.9 -57.8,-60.68 -57.8,-59.46 -57.8,-58.24 -57.8,-57.02 -57.8,-55.8 -57.8,-55.8 -58.8,-55.8 -59.8,-55.8 -60.8,-55.8 -61.8,-55.8 -62.8,-55.8 -63.8,-55.8 -64.8,-55.8 -65.8,-55.8 -66.8,-55.8 -67.8,-57.02 -67.8,-58.24 -67.8,-59.46 -67.8,-60.68 -67.8,-61.9 -67.8,-63.12 -67.8,-64.34 -67.8,-65.56 -67.8,-66.78 -67.8,-68 -67.8,-68 -66.8,-68 -65.8,-68 -64.8,-68 -63.8,-68 -62.8,-68 -61.8,-68 -60.8,-68 -59.8,-68 -58.8,-68 -57.8))", "dataset_titles": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems; Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203; Bruce Plateau Accumulation O18 2009-1900; Easten Antarctic Peninsula Surface Sediment Diatom Data; LMG13-11 JKC-1 Paleoceanographic data; Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; NBP1001 cruise data; NBP1203 cruise data; Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Sediment samples (full data link not provided)", "datasets": [{"dataset_uid": "601306", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601306"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}, {"dataset_uid": "000226", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203", "url": "https://doi.org/10.1594/ieda/320821"}, {"dataset_uid": "600073", "doi": "10.15784/600073", "keywords": "Antarctica; Antarctic Peninsula; Araon1304; Biota; LARISSA; Larsen B Ice Shelf; NBP1001; NBP1203; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "people": "Vernet, Maria", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems", "url": "https://www.usap-dc.org/view/dataset/600073"}, {"dataset_uid": "600167", "doi": "10.15784/600167", "keywords": "Antarctica; Antarctic Peninsula; Bruce Plateau; Glaciology; Ice Core Records; Isotope; LARISSA; Paleoclimate; Sample/collection Description; Sample/Collection Description; Snow Accumulation", "people": "Thompson, Lonnie G.; Mosley-Thompson, Ellen", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Bruce Plateau Accumulation O18 2009-1900", "url": "https://www.usap-dc.org/view/dataset/600167"}, {"dataset_uid": "601346", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601346"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}, {"dataset_uid": "601211", "doi": "10.15784/601211", "keywords": "Antarctica; Antarctic Peninsula; Benthos; Biota; Diatom; Geology/Geophysics - Other; LMG0502; Marine Geoscience; Marine Sediments; Microscope; NBP0003; NBP0107; NBP0603; NBP1203; R/v Nathaniel B. Palmer; Surface Sediment", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Easten Antarctic Peninsula Surface Sediment Diatom Data", "url": "https://www.usap-dc.org/view/dataset/601211"}, {"dataset_uid": "000145", "doi": "", "keywords": null, "people": null, "repository": "AMGRF", "science_program": null, "title": "Sediment samples (full data link not provided)", "url": "http://arf.fsu.edu/"}, {"dataset_uid": "000142", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1001 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1001"}, {"dataset_uid": "601485", "doi": "10.15784/601485", "keywords": "Antarctica; Antarctic Peninsula; Delta 13C; Delta 18O; Paleoceanography; Temperature", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": "LARISSA", "title": "LMG13-11 JKC-1 Paleoceanographic data", "url": "https://www.usap-dc.org/view/dataset/601485"}, {"dataset_uid": "000143", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1203 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}, {"dataset_uid": "601305", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601305"}, {"dataset_uid": "601345", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601345"}], "date_created": "Thu, 01 Feb 2018 00:00:00 GMT", "description": "Like no other region on Earth, the northern Antarctic Peninsula represents a spectacular natural laboratory of climate change and provides the opportunity to study the record of past climate and ecological shifts alongside the present-day changes in one of the most rapidly warming regions on Earth. This award supports the cryospheric and oceano-graphic components of an integrated multi-disciplinary program to address these rapid and fundamental changes now taking place in Antarctic Peninsula (AP). By making use of a marine research platform (the RV NB Palmer and on-board helicopters) and additional logistical support from the Argentine Antarctic program, the project will bring glaciologists, oceanographers, marine geologists and biologists together, working collaboratively to address fundamentally interdisciplinary questions regarding climate change. The project will include gathering a new, high-resolution paleoclimate record from the Bruce Plateau of Graham Land, and using it to compare Holocene- and possibly glacial-epoch climate to the modern period; investigating the stability of the remaining Larsen Ice Shelf and rapid post-breakup glacier response ? in particular, the roles of surface melt and ice-ocean interactions in the speed-up and retreat; observing the contribution of, and response of, oceanographic systems to ice shelf disintegration and ice-glacier interactions. Helicopter support on board will allow access to a wide range of glacial and geological areas of interest adjacent to the Larsen embayment. At these locations, long-term in situ glacial monitoring, isostatic uplift, and ice flow GPS sites will be established, and high-resolution ice core records will be obtained using previously tested lightweight drilling equipment. Long-term monitoring of deep water outflow will, for the first time, be integrated into changes in ice shelf extent and thickness, bottom water formation, and multi-level circulation by linking near-source observations to distal sites of concentrated outflow. The broader impacts of this international, multidisciplinary effort are that it will significantly advance our understanding of linkages amongst the earth\u0027s systems in the Polar Regions, and are proposed with international participation (UK, Spain, Belgium, Germany and Argentina) and interdisciplinary engagement in the true spirit of the International Polar Year (IPY). It will also provide a means of engaging and educating the public in virtually all aspects of polar science and the effects of ongoing climate change. The research team has a long record of involving undergraduates in research, educating high-performing graduate students, and providing innovative and engaging outreach products to the K-12 education and public media forums. Moreover, forging the new links both in science and international Antarctic programs will provide a continuing legacy, beyond IPY, of improved understanding and cooperation in Antarctica.", "east": -55.8, "geometry": "POINT(-61.9 -62.8)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e BOX CORE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ICE AUGERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SNOW DENSITY CUTTER", "is_usap_dc": true, "keywords": "Paleoclimate; Megafauna; USAP-DC; AMD; Amd/Us; Antarctica; Climate Change; LABORATORY; Climate Variability; Multi-Disciplinary; Cryosphere; NBP1001; FIELD SURVEYS; Not provided; Antarctic Peninsula; R/V NBP; FIELD INVESTIGATION; USA/NSF; Ice Core; Holocene", "locations": "Antarctica; Antarctic Peninsula", "north": -57.8, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Truffer, Martin; Gordon, Arnold; Huber, Bruce; Mosley-Thompson, Ellen; Leventer, Amy; Vernet, Maria; Smith, Craig; Thompson, Lonnie G.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "AMGRF; MGDS; R2R; USAP-DC", "science_programs": "LARISSA", "south": -67.8, "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "uid": "p0000101", "west": -68.0}, {"awards": "1245899 Kowalewski, Douglas", "bounds_geometry": "POLYGON((-180 -70,-174 -70,-168 -70,-162 -70,-156 -70,-150 -70,-144 -70,-138 -70,-132 -70,-126 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-126 -85,-132 -85,-138 -85,-144 -85,-150 -85,-156 -85,-162 -85,-168 -85,-174 -85,180 -85,178 -85,176 -85,174 -85,172 -85,170 -85,168 -85,166 -85,164 -85,162 -85,160 -85,160 -83.5,160 -82,160 -80.5,160 -79,160 -77.5,160 -76,160 -74.5,160 -73,160 -71.5,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": "Region Climate Model Output Plio-Pleistocene", "datasets": [{"dataset_uid": "601080", "doi": "10.15784/601080", "keywords": "Antarctica; Climate Model; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; McMurdo; Paleoclimate; Ross Sea", "people": "Kowalewski, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Region Climate Model Output Plio-Pleistocene", "url": "https://www.usap-dc.org/view/dataset/601080"}], "date_created": "Tue, 16 Jan 2018 00:00:00 GMT", "description": "Intellectual Merit: The PIs propose to complement the ANDRILL marine record with a terrestrial project that will provide chronological control for past fluctuations of the West Antarctic Ice Sheet (WAIS) and alpine glaciers in McMurdo Sound. The project will develop high-resolution maps of drifts deposited from grounded marine-based ice and alpine glaciers on islands and peninsulas in McMurdo Sound. In addition, the PIs will acquire multi-clast/multi-nuclide cosmogenic analyses of these mapped drift sheets and alpine moraines and use regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession. The PIs will make use of geological records for ice sheet and alpine glacier fluctuations preserved on the flanks of Mount Discovery, Black Island, and Brown Peninsula. Drifts deposited from grounded, marine-based ice will yield spatial constraints for former advances and retreats of the WAIS. Moraines from alpine glaciers, hypothesized to be of interglacial origin, could yield a first-order record of hydrologic change in the region. Synthesizing the field data, the team proposes to improve the resolution of existing regional-scale climate models for the Ross Embayment. The overall approach and anticipated results will provide the first steps towards linking the marine and terrestrial records in this critical sector of Antarctica. Broader impacts: Results from the proposed work will be integrated with outreach programs at Boston University, Columbia University, and Worcester State University. The team will actively collaborate with the American Museum of Natural History to feature this project prominently in museum outreach. The team will also include a PolarTREC teacher as a member of the research team. The geomorphological results will be presented in 3D at Boston University?s Antarctic Digital Image Analyses Lab. The research will form the basis of a PhD dissertation at Boston University.", "east": -120.0, "geometry": "POINT(-160 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kowalewski, Douglas", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Collaborative Research: West Antarctic Ice Sheet stability, Alpine Glaciation, and Climate Variability: a Terrestrial Perspective from Cosmogenic-nuclide Dating in McMurdo Sound", "uid": "p0000391", "west": 160.0}, {"awards": "1543380 Shadwick, Elizabeth", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG1704", "datasets": [{"dataset_uid": "002732", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1704", "url": "https://www.rvdata.us/search/cruise/LMG1704"}, {"dataset_uid": "001364", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1704"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "Interest in the reduced alkalinity of high latitude waters under conditions of enhanced CO2 uptake from the atmosphere have been the impetus of numerous recent studies of bio-stressors in the polar marine environment. The project seeks to improve our understanding of the variance of coastal Southern Ocean carbonate species (CO2 system), its diurnal and inter-annual variability, by acquiring autonomous, high frequency observations from an Antarctic coastal mooring(s). A moored observing system co-located within the existing Palmer LTER array will measure pH, CO2 partial pressure, temperature, salinity and dissolved oxygen with 3-hour frequency in this region of the West Antarctic Peninsula continental shelf. Such observations will help estimate the dominant physical and biological controls on the seasonal variations in the CO2 system in coastal Antarctic waters, including the sign, seasonality and the flux of the net annual air-sea exchange of carbon dioxide. The Palmer LTER site is experiencing rapid ecological change in the West Antarctic Peninsula, a region that is warming at rates faster than any other region of coastal Antarctica.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V LMG; LMG1704", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Shadwick, Elizabeth; Shadwick, Elizabeth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Resolving CO2 System Seasonality in the West Antarctic Peninsula with Autonomous Observations", "uid": "p0000875", "west": null}, {"awards": "1141939 Lubin, Dan", "bounds_geometry": "POLYGON((-167.0365 -77.5203,-166.96385 -77.5203,-166.8912 -77.5203,-166.81855 -77.5203,-166.7459 -77.5203,-166.67325 -77.5203,-166.6006 -77.5203,-166.52795 -77.5203,-166.4553 -77.5203,-166.38265 -77.5203,-166.31 -77.5203,-166.31 -77.52527,-166.31 -77.53024,-166.31 -77.53521,-166.31 -77.54018,-166.31 -77.54515,-166.31 -77.55012,-166.31 -77.55509,-166.31 -77.56006,-166.31 -77.56503,-166.31 -77.57,-166.38265 -77.57,-166.4553 -77.57,-166.52795 -77.57,-166.6006 -77.57,-166.67325 -77.57,-166.7459 -77.57,-166.81855 -77.57,-166.8912 -77.57,-166.96385 -77.57,-167.0365 -77.57,-167.0365 -77.56503,-167.0365 -77.56006,-167.0365 -77.55509,-167.0365 -77.55012,-167.0365 -77.54515,-167.0365 -77.54018,-167.0365 -77.53521,-167.0365 -77.53024,-167.0365 -77.52527,-167.0365 -77.5203))", "dataset_titles": "Shortwave Spectroradiometer Data from Ross Island, Antarctica", "datasets": [{"dataset_uid": "601074", "doi": "10.15784/601074", "keywords": "Antarctica; Atmosphere; Meteorology; Radiosounding; Ross Island", "people": "Lubin, Dan", "repository": "USAP-DC", "science_program": null, "title": "Shortwave Spectroradiometer Data from Ross Island, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601074"}], "date_created": "Wed, 20 Dec 2017 00:00:00 GMT", "description": "Antarctic clouds constitute an important parameter of the surface radiation budget and thus play a significant role in Antarctic climate and climate change. The variability in, and long term trends of, cloud optical and microphysical properties are therefore fundamental in parameterizing the mixed phase (water-snow-ice) coastal Antarctic stratiform clouds experienced around the continent. Using a spectoradiometer that covers the wavelength range of 350 to 2200nm, the downwelled spectral irradiance at the earth surface (Ross Island) will be used to retrieve the optical depth, thermodynamic phase, liquid water droplet effective radius, and ice-cloud effective particle size of overhead clouds, at hourly intervals and for an austral summer season (Oct-March). Based on the very limited data sets that exist for the maritime Antarctic, expectations are that Ross Island (Lat 78 S) should exhibit clouds with: a) An abundance of supercooled liquid water, and related mixed-phase cloud processes b) Cloud nucleation from year round biogenic and oceanic sources, in an otherwise pristine environment c) Simple cloud geometries of predominantly stratiform cloud decks Increased understanding of the cloud properties in the region of the main USAP base, McMurdo station is also relevant to operational weather forecasting relevant to aviation. A range of educational and outreach activities are associate with the project, including provision of workshops for high school teachers will be carried out.", "east": -166.31, "geometry": "POINT(-166.67325 -77.54515)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; USAP-DC", "locations": null, "north": -77.5203, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Lubin, Dan", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.57, "title": "Antarctic Cloud Physics: Fundamental Observations from Ross Island", "uid": "p0000327", "west": -167.0365}, {"awards": "1460449 Goehring, Brent; 1341420 Balco, Gregory; 1341364 Todd, Claire", "bounds_geometry": "POLYGON((164.08 -74.6,164.0842 -74.6,164.0884 -74.6,164.0926 -74.6,164.0968 -74.6,164.101 -74.6,164.1052 -74.6,164.1094 -74.6,164.1136 -74.6,164.1178 -74.6,164.122 -74.6,164.122 -74.6023,164.122 -74.6046,164.122 -74.6069,164.122 -74.6092,164.122 -74.6115,164.122 -74.6138,164.122 -74.6161,164.122 -74.6184,164.122 -74.6207,164.122 -74.623,164.1178 -74.623,164.1136 -74.623,164.1094 -74.623,164.1052 -74.623,164.101 -74.623,164.0968 -74.623,164.0926 -74.623,164.0884 -74.623,164.0842 -74.623,164.08 -74.623,164.08 -74.6207,164.08 -74.6184,164.08 -74.6161,164.08 -74.6138,164.08 -74.6115,164.08 -74.6092,164.08 -74.6069,164.08 -74.6046,164.08 -74.6023,164.08 -74.6))", "dataset_titles": "Interface to observational data associated with exposure-age measurements and resulting calculated ages. Dynamic content, updated.", "datasets": [{"dataset_uid": "200196", "doi": null, "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data associated with exposure-age measurements and resulting calculated ages. Dynamic content, updated.", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Wed, 18 Oct 2017 00:00:00 GMT", "description": "The investigators will map glacial deposits and date variations in glacier variability at several ice-free regions in northern Victoria Land, Antarctica. These data will constrain the nature and timing of past ice thickness changes for major glaciers that drain into the northwestern Ross Sea. This is important because during the Last Glacial Maximum (15,000 - 18,000 years ago) these glaciers were most likely flowing together with grounded ice from both the East and West Antarctic Ice Sheets that expanded across the Ross Sea continental shelf to near the present shelf edge. Thus, the thickness of these glaciers was most likely controlled in part by the extent and thickness of the Ross Sea ice sheet and ice shelf. The data the PIs propose to collect can provide constraints on the position of the grounding line in the western Ross Sea during the Last Glacial Maximum, the time that position was reached, and ice thickness changes that occurred after that time. The primary intellectual merit of this project will be to improve understanding of a period of Antarctic ice sheet history that is relatively unconstrained at present and also potentially important in understanding past ice sheet-sea level interactions. This proposal will support an early career researcher\u0027s ongoing program of undergraduate education and research that is building a socio-economically diverse student body with students from backgrounds underrepresented in the geosciences. This proposal will also bring an early career researcher into Antarctic research.", "east": 164.122, "geometry": "POINT(164.101 -74.6115)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; Cosmogenic Dating; Exposure Age; LABORATORY; NOT APPLICABLE; Amd/Us; Ross Sea", "locations": "Ross Sea", "north": -74.6, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Goehring, Brent; Balco, Gregory; Todd, Claire", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -74.623, "title": "Collaborative Research: Terrestrial Exposure-Age Constraints on the last Glacial Maximum Extent of the Antarctic Ice Sheet in the Western Ross Sea", "uid": "p0000306", "west": 164.08}, {"awards": "1341284 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.5,161.2 -77.5,161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163 -77.525,163 -77.55,163 -77.575,163 -77.6,163 -77.625,163 -77.65,163 -77.675,163 -77.7,163 -77.725,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,161.8 -77.75,161.6 -77.75,161.4 -77.75,161.2 -77.75,161 -77.75,161 -77.725,161 -77.7,161 -77.675,161 -77.65,161 -77.625,161 -77.6,161 -77.575,161 -77.55,161 -77.525,161 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Oct 2017 00:00:00 GMT", "description": "Paragraph for Laypersons: This research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations. Paragraph for Scientific Community: Rock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure dating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.", "east": 163.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.75, "title": "Origin and Climatic Significance of Rock Glaciers in the McMurdo Dry Valleys: Assessing Spatial and Temporal Variability", "uid": "p0000297", "west": 161.0}, {"awards": "1142085 Alley, Richard", "bounds_geometry": null, "dataset_titles": "Firn-temperature time series in Dronning Maud Land, East Antarctica", "datasets": [{"dataset_uid": "601050", "doi": "10.15784/601050", "keywords": "Antarctica; Borehole Logging; Dronning Maud Land; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Physical Properties; Snow; Temperature", "people": "Muto, Atsu", "repository": "USAP-DC", "science_program": null, "title": "Firn-temperature time series in Dronning Maud Land, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601050"}], "date_created": "Mon, 11 Sep 2017 00:00:00 GMT", "description": "Alley/1142085 This award supports a project to continue the collection and analyses of firn temperature data from three automated firn thermal profiling units deployed in Dronning Maud Land sector of East Antarctica as part of the Norway-US IPY Traverse project between 2007 and 2009. The intellectual merits of this project are as follows: 1) to constrain and improve the parameterization of firn thermal properties (thermal conductivity and specific heat capacity) that are required for the borehole paleothermometry, 2) to study the change in firn temperature since the deployment of thermal profiling units ~5 years ago and derive the surface temperature trend for that time period, and 3) to compare and contrast the surface temperatures and their trends derived from the measured firn temperatures and satellite thermal infrared data for the past three decades. The project also involves acquiring and deploying an automated system to record transient temperatures at multiple depths in the top 16 meters of the shallow borehole at Dome Fuji, to provide useful data and to prepare for the possibility of conducting temperature-logging in the existing deep (3035 m) and shallow (112 m) boreholes at Dome Fuji in the near future. The preparation of the shallow borehole and the installation of the automated system will be carried out by collaborators from the Japanese Antarctic Research Expedition (JARE) in 2012-13 Antarctic field season. The data collected by this automated system will be used to constrain the thermal properties of upper firn layer at Dome Fuji, as well as comparing with data from other sites, increasing the geographic extent of these studies. The broader impacts of the project include presentation of results at scientific conferences and publication of results in peer-reviewed journals. Public outreach will include targeted work with science teachers and middle school students.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Alley, Richard", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Revealing Late Holocence Climate Variability in Antarctica from Borehole Paleothermometry", "uid": "p0000440", "west": null}, {"awards": "1443444 Yuan, Xiaojun", "bounds_geometry": "POLYGON((65.4503 -63.5143,67.2063 -63.5143,68.9623 -63.5143,70.7183 -63.5143,72.4743 -63.5143,74.2303 -63.5143,75.9863 -63.5143,77.7423 -63.5143,79.4983 -63.5143,81.2543 -63.5143,83.0103 -63.5143,83.0103 -64.09423,83.0103 -64.67416,83.0103 -65.25409,83.0103 -65.83402,83.0103 -66.41395,83.0103 -66.99388,83.0103 -67.57381,83.0103 -68.15374,83.0103 -68.73367,83.0103 -69.3136,81.2543 -69.3136,79.4983 -69.3136,77.7423 -69.3136,75.9863 -69.3136,74.2303 -69.3136,72.4743 -69.3136,70.7183 -69.3136,68.9623 -69.3136,67.2063 -69.3136,65.4503 -69.3136,65.4503 -68.73367,65.4503 -68.15374,65.4503 -67.57381,65.4503 -66.99388,65.4503 -66.41395,65.4503 -65.83402,65.4503 -65.25409,65.4503 -64.67416,65.4503 -64.09423,65.4503 -63.5143))", "dataset_titles": "CTD Data Acquired by R/V Xue Long in the Prydz Bay- Amery Ice Shelf Region, 2015-2017", "datasets": [{"dataset_uid": "600174", "doi": "10.15784/600174", "keywords": "CTD Data; Oceans; Physical Oceanography; Prydz Bay; Sample/collection Description; Sample/Collection Description; Southern Ocean; Xue Long", "people": "Yuan, Xiaojun", "repository": "USAP-DC", "science_program": null, "title": "CTD Data Acquired by R/V Xue Long in the Prydz Bay- Amery Ice Shelf Region, 2015-2017", "url": "https://www.usap-dc.org/view/dataset/600174"}], "date_created": "Tue, 20 Jun 2017 00:00:00 GMT", "description": "Antarctic Bottom Water (AABW) formation is a key component in setting the global thermohaline (overturning) circulation. Recent studies infer a reduction of the AABW component from reduced volume of AABW entering global deep ocean basins around the Antarctic continent. It is important to obtain better estimates of AABW production rate in its source areas, and to investigate whether the global overturning circulation is slowing down. The project will continue fieldwork with CTD/LADCP surveys including 2 yearly repeat sections, mooring recoveries and deployments. Seasonal-interannual variability of CDW intrusion, dense shelf water accumulation and export as well as overflow from the Prydz Bay shelf will also be observed. The Prydz Bay- Amery Ice Shelf region has been suggested as a key AABW production site. USAP access to this remote region of the Antarctic continent is challenging. The project will involve fieldwork to be carried out with Danish and Chinese collaboration aboard the Chinese research vessel, Xue Long. A high-resolution regional ocean-sea ice coupled model will be developed to allow time and space continuous three-dimensional ocean state estimation. Both in-situ and remote sensing observations along with the modeling simulation results will be used to investigate (i) the local atmosphere-ocean-sea ice interaction and shelf processes that produce dense shelf water and (ii) the dynamic processes that control the shelf water export.", "east": 83.0103, "geometry": "POINT(74.2303 -66.41395)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -63.5143, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Yuan, Xiaojun", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -69.3136, "title": "Collaborative Research: Contribution of Prydz Bay Shelf Water to Antarctic Bottom Water Formation", "uid": "p0000295", "west": 65.4503}, {"awards": "1341360 Steig, Eric", "bounds_geometry": "POINT(106 -77.5)", "dataset_titles": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "datasets": [{"dataset_uid": "601031", "doi": "10.15784/601031", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Snow Pit; WAIS Divide Ice Core", "people": "Steig, Eric J.; Schoenemann, Spruce", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "url": "https://www.usap-dc.org/view/dataset/601031"}], "date_created": "Tue, 06 Jun 2017 00:00:00 GMT", "description": "Steig/1341360 This award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.", "east": 106.0, "geometry": "POINT(106 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -77.5, "title": "Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores", "uid": "p0000316", "west": 106.0}, {"awards": "1443260 Conway, Howard", "bounds_geometry": "POLYGON((159 -76.68,159.03 -76.68,159.06 -76.68,159.09 -76.68,159.12 -76.68,159.15 -76.68,159.18 -76.68,159.21 -76.68,159.24 -76.68,159.27 -76.68,159.3 -76.68,159.3 -76.697,159.3 -76.714,159.3 -76.731,159.3 -76.748,159.3 -76.765,159.3 -76.782,159.3 -76.799,159.3 -76.816,159.3 -76.833,159.3 -76.85,159.27 -76.85,159.24 -76.85,159.21 -76.85,159.18 -76.85,159.15 -76.85,159.12 -76.85,159.09 -76.85,159.06 -76.85,159.03 -76.85,159 -76.85,159 -76.833,159 -76.816,159 -76.799,159 -76.782,159 -76.765,159 -76.748,159 -76.731,159 -76.714,159 -76.697,159 -76.68))", "dataset_titles": "2015-2016 GPR Field Report for Allan Hills Shallow Ice Coring; Ground-based ice-penetrating radar profiles collected on the Allan Hills blue ice region", "datasets": [{"dataset_uid": "601005", "doi": "10.15784/601005", "keywords": "Allan Hills; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Navigation; Radar", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Ground-based ice-penetrating radar profiles collected on the Allan Hills blue ice region", "url": "https://www.usap-dc.org/view/dataset/601005"}, {"dataset_uid": "601668", "doi": "10.15784/601668", "keywords": "Allan Hills; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; GPR; Ice Core; Report", "people": "MacKay, Sean; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "2015-2016 GPR Field Report for Allan Hills Shallow Ice Coring", "url": "https://www.usap-dc.org/view/dataset/601668"}], "date_created": "Tue, 02 May 2017 00:00:00 GMT", "description": "Marine paleoclimate archives show that approximately one million years ago Earth\u0027s climate transitioned from 40,000-year glacial /interglacial cycles to 100,000-year cycles. This award will support a study designed to map the distribution of one million year-old ice in the Allan Hills Blue Ice Area, Antarctica using state-of-the-art ground penetrating radar. The Allen Hills was demonstrated to contain a continuous record of the past 400,000 years and is also the collection location of the oldest ice samples (990,000 years) yet recovered. The maps resulting from this study will be used to select an ice-core drilling site at which a million-plus year-old continuous record of climate could be recovered. Ice cores contain the only kind of record to directly capture atmospheric gases and aerosols, but no ice-core-based climate record yet extends continuously beyond the past 800,000 years. A million-plus year-old record will allow better understanding of the major mechanisms and driving forces of natural climate variability in a world with 100,000-year glacial/interglacial cycles. The project will support two early career scientists in collaboration with senior scientists, as well as a graduate student, and will conduct outreach to schools and the public. The Allan Hills Blue Ice Area preserves a continuous climate record covering the last 400,000 years along an established glaciological flow line. Two kilometers to the east of this flow line, the oldest ice on Earth (~1 million years old) is found only 120 m below the surface. Meteorites collected in the area are reported to be as old as 1.8 million years, suggesting still older ice may be present. Combined, these data strongly suggest that the Allen Hills area could contain a continuous, well-resolved environmental record, spanning at least the last million years. As such, this area has been selected as an upcoming target for the new Intermediate Depth Ice Core Drill by the US Ice Core Working Group. This drill will recover a higher-quality core than previous dry drilling attempts. This project will conduct a comprehensive ground penetrating radar survey aimed at tracing the signature of the million-year-old ice layer throughout the region. The resulting map will be used to select a drill site from which an ice core containing the million-plus year-old continuous climate record will be collected. The proposed activities are a necessary precursor to the collection of the oldest known ice on Earth. Ice cores provide a robust reconstruction of past climate and extending this record beyond the 800,000 years currently available will open new opportunities to study the climate system. The data collected will also be used to investigate the bedrock and ice flow parameters favorable to the preservation of old ice, which may allow targeted investigation of other blue ice areas in Antarctica.", "east": 159.3, "geometry": "POINT(159.15 -76.765)", "instruments": null, "is_usap_dc": true, "keywords": "Allan Hills; FIELD SURVEYS; ICE SHEETS", "locations": "Allan Hills", "north": -76.68, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.85, "title": "Collaborative Research: Allan HILLs Englacial Site (AHILLES) Selection", "uid": "p0000385", "west": 159.0}, {"awards": "1246223 Hastings, Meredith", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "WAIS Divide WDC06A Nitrate Isotope Record", "datasets": [{"dataset_uid": "601022", "doi": "10.15784/601022", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Nitrate; WAIS Divide; WAIS Divide Ice Core", "people": "Buffen, Aron; Hastings, Meredith", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide WDC06A Nitrate Isotope Record", "url": "https://www.usap-dc.org/view/dataset/601022"}], "date_created": "Tue, 02 May 2017 00:00:00 GMT", "description": "Hastings/1246223 This award supports a project with the aim of distinguishing the sources of nitrate deposition to the West Antarctic Ice Sheet (WAIS) using isotopic ratios snow in archive snow and ice samples. The isotopic composition of nitrate has been shown to contain information about the source of the nitrate (i.e. nitrogen oxides = NOx = NO+NO2) and the oxidation processes that convert NOx to nitrate in the atmosphere prior to deposition. A difficulty in interpreting records in the context of NOx sources is that nitrate can be post-depositionally processed in surface snow, such that the archived record does not reflect the composition of the atmosphere. This intellectual merit of this work specifically aims to investigate variability in the isotopic composition of nitrate in snow and ice from the WAIS in the context of accumulation rate, NOx source emissions, and atmospheric chemistry. These records will be interpreted in the context of our understanding of biospheric (biomass burning, microbial processes in soils), atmospheric (lightning, transport, chemistry), and climate (temperature, accumulation rate) changes over time. A graduate student will be supported as part of this project, and both graduate student and PI will be involved in communicating the utility and results of polar research to elementary school students in the Providence, RI area. The broader impacts of the project also include making efforts to attract more young, female scientists to polar research by establishing a connection between the Earth Science Women\u0027s Network (ESWN), an organization PI Hastings helped to establish, and the Association of Polar Early Career Scientists (APECS). Finally, results of all measurements will be presented at relevant conferences, made available publicly and published in peer-reviewed journals.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hastings, Meredith", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Investigating Source, Chemistry and Climate changes using the Isotopic Composition of Nitrate in Antarctic Snow and Ice", "uid": "p0000399", "west": -112.1115}, {"awards": "0538520 Thiemens, Mark; 0538049 Steig, Eric", "bounds_geometry": "POINT(-112.085 -79.5)", "dataset_titles": "Multiple Isotope Analysis of Sulfate in the West Antarctic Ice Sheet Divide Ice Core; WAIS Divide sulfate and nitrate isotopes; WAIS ice core isotope data #387, 385 (full data link not provided)", "datasets": [{"dataset_uid": "002512", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "WAIS ice core isotope data #387, 385 (full data link not provided)", "url": "http://www.waisdivide.unh.edu/"}, {"dataset_uid": "609479", "doi": "10.7265/N5BG2KXH", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Thiemens, Mark H.", "repository": "USAP-DC", "science_program": null, "title": "Multiple Isotope Analysis of Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "url": "https://www.usap-dc.org/view/dataset/609479"}, {"dataset_uid": "601007", "doi": "10.15784/601007", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Nitrate; Oxygen Isotope; Sulfate; WAIS Divide; WAIS Divide Ice Core", "people": "Steig, Eric J.; Alexander, Becky", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide sulfate and nitrate isotopes", "url": "https://www.usap-dc.org/view/dataset/601007"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "0538520\u003cbr/\u003eThiemens\u003cbr/\u003eThis award supports a project to develop the first complete record of multiple isotope ratios of nitrate and sulfate covering the last ~100,000 years, from the deep ice core planned for the central ice divide of the West Antarctic Ice Sheet (WAIS). The WAIS Divide ice core will be the highest resolution long ice core obtained from Antarctica and we can expect important complementary information to be available, including accurate knowledge of past accumulation rates, temperatures, and compounds such as H2O2, CO and CH4. These compounds play significant roles in global atmospheric chemistry and climate. Especially great potential lies in the use of multiple isotope signatures. The unique mass independent fractionation (MIF) 17O signature of ozone is observed in both nitrate and sulfate, due to the interaction of their precursors with ozone. The development of methods to measure the multiple-isotope composition of small samples of sulfate and nitrate makes continuous high resolution measurements on ice cores feasible for the first time. Recent work has shown that such measurements can be used to determine the hydroxyl radial (OH) and ozone (O3) concentrations in the paleoatmosphere as well as to apportion sulfate and nitrate sources. There is also considerable potential in using these isotope measurements to quantify post depositional changes. In the first two years, continuous measurements from the upper ~100-m of ice at WAIS divide will be obtained, to provide a detailed look at seasonal through centennial scale variability. In the third year, measurements will be made throughout the available depth of the deep core (expected to reach ~500 m at this time). The broader impacts of the project include applications to diverse fields including atmospheric chemistry, glaciology, meteorology, and paleoclimatology. Because nitrate and sulfate are important atmospheric pollutants, the results will also have direct and relevance to global environmental policy. This project will coincide with the International Polar Year (2007-2008), and contributes to goals of the IPY, which include the fostering of interdisciplinary research toward enhanced understanding of atmospheric chemistry and climate in the polar regions.", "east": -112.085, "geometry": "POINT(-112.085 -79.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Isotope Ratios; Temperature; Sulfate; West Antarctic; Paleoatmosphere; LABORATORY; Ice Core; Ice Core Data; Mass Independent Fractionation; FIELD SURVEYS; Not provided; Accumulation Rate; Oxygen Isotope; FIELD INVESTIGATION; Ice Core Chemistry; Isotope", "locations": "West Antarctic", "north": -79.5, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Alexander, Becky; Steig, Eric J.; Thiemens, Mark H.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "Project website", "repositories": "Project website; USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.5, "title": "Collaborative Research: Multiple-isotope Analysis of Nitrate and Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "uid": "p0000020", "west": -112.085}, {"awards": "1347911 Loeb, Valerie", "bounds_geometry": "POLYGON((-66 -54,-65.2 -54,-64.4 -54,-63.6 -54,-62.8 -54,-62 -54,-61.2 -54,-60.4 -54,-59.6 -54,-58.8 -54,-58 -54,-58 -54.8,-58 -55.6,-58 -56.4,-58 -57.2,-58 -58,-58 -58.8,-58 -59.6,-58 -60.4,-58 -61.2,-58 -62,-58.8 -62,-59.6 -62,-60.4 -62,-61.2 -62,-62 -62,-62.8 -62,-63.6 -62,-64.4 -62,-65.2 -62,-66 -62,-66 -61.2,-66 -60.4,-66 -59.6,-66 -58.8,-66 -58,-66 -57.2,-66 -56.4,-66 -55.6,-66 -54.8,-66 -54))", "dataset_titles": "Zooplankton samples, analyses, and underwater video.", "datasets": [{"dataset_uid": "000198", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Zooplankton samples, analyses, and underwater video.", "url": "http://www.bco-dmo.org/project/683961"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "A 50+ year warming trend in the Southern Ocean has been most dramatic in Drake Passage and likely impacts ecosystem structure here. Acoustic Doppler Current Profiler (ADCP) records from multiple ?L.M. Gould? supply transits of Drake Passage from 1999 to present demonstrate spatial and temporal variability in acoustics backscattering. Acoustics backscattering strength in the upper water column corresponds to zooplankton and nekton biomass that supports predator populations. However, for much of Drake Passage the identity of taxa contributing to this acoustically detected biomass is not known. This project would introduce a biological component to ?L.M. Gould? transits of Drake Passage with the goal of determining the identity of taxa responsible for the backscattering records obtained by ADCP and relating these to higher trophic levels (seabird/marine mammal). Net sampling during spring, summer and fall transits will permit assessment of diel and seasonal changes in the abundance and taxonomic composition of zooplankton and top predators represented between Patagonia and the Antarctic Peninsula. Net samples and depth-referenced video records taken in conjunction with ADCP profiles will permit the identification of the dominant acoustic backscatters in the 3 biogeographic regions represented here, the Subantarctic, Polar Frontal, and Antarctic Zones. The validity of dominant backscattering taxa in the Antarctic Zone will be tested by comparing the ADCP records with abundant zooplankton data collected off the Antarctic Peninsula during January-March 1999-2009 as well with long-term top predator surveys. The broader impacts also include a cruise blog, the production of an article for an online outreach publication based at Moss Landing Marine Labs and a YouTube video featuring shipboard research in the Southern Ocean.", "east": -58.0, "geometry": "POINT(-62 -58)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -54.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Loeb, Valerie; Santora, Jarrod", "platforms": "Not provided", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -62.0, "title": "Pilot Study: Addition of Biological Sampling to Drake Passage Transits of the \"L.M. Gould\"", "uid": "p0000314", "west": -66.0}, {"awards": "1246320 Kruckenberg, Seth", "bounds_geometry": "POINT(-144.75 -76.53)", "dataset_titles": null, "datasets": null, "date_created": "Mon, 19 Sep 2016 00:00:00 GMT", "description": "Intellectual Merit: The PI proposes an investigation of mantle xenoliths entrained within a suite of ~1.4 Ma mafic volcanic centers in the Fosdick Mountains, Antarctica. These recently entrained mantle xenoliths offer a unique opportunity to characterize the West Antarctic lithospheric mantle that has been subject to active modification from Cretaceous to Present by plate-boundary processes, such as orthogonal to oblique plate convergence, intracontinental rifting, continental breakup, and Neogene volcanism. These volcanic centers derive from heterogeneous mantle sources and host a compositionally diverse suite of mantle xenoliths that have varied mineral assemblages and microstructures. The proposed research has two complementary goals: to assess structural and compositional heterogeneity within the upper mantle and the variability of intrinsic and extrinsic variables at a variety of lithospheric levels; and to use textural and compositional characterization of the xenolith suite to elucidate possible causes of heterogeneous seismic anisotropy within the Marie Byrd Land mantle lithosphere and inform competing hypotheses explaining the active volcanism, thermal anomaly, and slow seismic velocities beneath West Antarctica. Furthermore, characterization of samples of the mantle beneath West Antarctica provides a type of \u0027ground truth\u0027 in support of contemporary ANET/POLENET seismology research that seeks to determine mantle composition, temperature, and sources of seismic anisotropy. Broader impacts: The PI is in his first-year as a tenure track faculty member at Boston College. A postdoctoral researcher will be trained in EBSD techniques, interdisciplinary polar research, and the mentoring of undergraduate investigators. Two Boston College undergraduates will participate in the research and a priority will be placed on selecting underrepresented minorities and first-generation college students. An existing sample suite assembled over more than 20 years of NSF sponsored field work, will be used. The PI will create a digital database for microstructural, textural, and xenolith data for rapid dissemination to the international Antarctic community.", "east": -144.75, "geometry": "POINT(-144.75 -76.53)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.53, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kruckenberg, Seth", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -76.53, "title": "Integrated Evaluation of Mantle Xenoliths from the Fosdick Mountains, Antarctica", "uid": "p0000400", "west": -144.75}, {"awards": "1246202 Hofmann, Gretchen", "bounds_geometry": "POLYGON((163.317388 -77.3354,163.6520742 -77.3354,163.9867604 -77.3354,164.3214466 -77.3354,164.6561328 -77.3354,164.990819 -77.3354,165.3255052 -77.3354,165.6601914 -77.3354,165.9948776 -77.3354,166.3295638 -77.3354,166.66425 -77.3354,166.66425 -77.386975,166.66425 -77.43855,166.66425 -77.490125,166.66425 -77.5417,166.66425 -77.593275,166.66425 -77.64485,166.66425 -77.696425,166.66425 -77.748,166.66425 -77.799575,166.66425 -77.85115,166.3295638 -77.85115,165.9948776 -77.85115,165.6601914 -77.85115,165.3255052 -77.85115,164.990819 -77.85115,164.6561328 -77.85115,164.3214466 -77.85115,163.9867604 -77.85115,163.6520742 -77.85115,163.317388 -77.85115,163.317388 -77.799575,163.317388 -77.748,163.317388 -77.696425,163.317388 -77.64485,163.317388 -77.593275,163.317388 -77.5417,163.317388 -77.490125,163.317388 -77.43855,163.317388 -77.386975,163.317388 -77.3354))", "dataset_titles": "mRNA sequencing - RNAseq; Nearshore pH, temperature, (salinity, depth) at mooring sites in McMurdo Sound, Antarctica, Overwinter 2011-2016; pH temp sal measurement data", "datasets": [{"dataset_uid": "601141", "doi": "10.15784/601141", "keywords": "Antarctica; McMurdo Sound; Mcmurdo Station; Mooring; Oceans; Ocean Temperature; PH; Physical Oceanography; Ross Sea; Sea Surface Temperature; Seawater Measurements; Southern Ocean; Temperature", "people": "Hofmann, Gretchen; Kapsenberg, Lydia; Hoshijima, Umihiko", "repository": "USAP-DC", "science_program": null, "title": "Nearshore pH, temperature, (salinity, depth) at mooring sites in McMurdo Sound, Antarctica, Overwinter 2011-2016", "url": "https://www.usap-dc.org/view/dataset/601141"}, {"dataset_uid": "000181", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "mRNA sequencing - RNAseq", "url": "http://www.bco-dmo.org/dataset/639502"}, {"dataset_uid": "002576", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "pH temp sal measurement data", "url": "https://www.bco-dmo.org/dataset/639502"}], "date_created": "Tue, 13 Sep 2016 00:00:00 GMT", "description": "The research supported in this project will examine the effects of environmental change on a key Antarctic marine invertebrate, a pelagic mollusk, the pteropod, Limacina helicina antarctica. There are two main activities in this project: (1) to deploy oceanographic equipment ? in this case, autonomously recording pH sensors called SeaFETs and other devices that record temperature and salinity, and (2) to use these environmental data in the laboratory at McMurdo Station to study the response of the marine invertebrates to future changes in water quality that is expected in the next few decades. Notably, changes in oceanic pH (aka ocean acidification) and ocean warming are projected to be particularly threatening to calcifying marine organisms in cold-water, high latitude seas, making tolerance data on these organisms a critical research need in Antarctic marine ecosystems. These Antarctic shelled-animals are especially vulnerable to dissolution stress from ocean acidification because they currently inhabit seawater that is barely at the saturation level to support biogenic calcification. Indeed, these polar animals are considered to be the \u0027first responders\u0027 to chemical changes in the surface oceans. Thus, this project will lead to information about the adaptive capacity of L. helcina antarctica. From an ecological perspective this is important because this animal is a critical part of the Antarctic food chain in coastal waters and changes in its abundance will impact other species. Finally, the research conducted in this project will serve as a training and educational opportunity for undergraduate and graduate students as well as postdoctoral scholars.", "east": 166.66425, "geometry": "POINT(164.990819 -77.593275)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.3354, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hofmann, Gretchen", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "BCO-DMO; USAP-DC", "science_programs": null, "south": -77.85115, "title": "Ocean Acidification Seascape: Linking Natural Variability and Anthropogenic changes in pH and Temperature to Performance in Calcifying Antarctic Marine Invertebrates", "uid": "p0000390", "west": 163.317388}, {"awards": "0944282 Hasiotis, Stephen", "bounds_geometry": "POINT(175 -86)", "dataset_titles": "Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica", "datasets": [{"dataset_uid": "600156", "doi": "10.15784/600156", "keywords": "Antarctica; Beardmore Glacier; Biota; Fossil; Paleoclimate; Sample/collection Description; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "people": "Hasiotis, Stephen", "repository": "USAP-DC", "science_program": null, "title": "Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600156"}], "date_created": "Fri, 03 Jun 2016 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis proposal will study the diversity, abundance, and tiering patterns of ichnofossils in continental and marine deposits of the Beacon Supergroup in the Beardmore Glacier Area (BGA). The PIs will focus on continental strata that contain a variety of ichnofossils and paleosols. Ichnofossils will be evaluated for their architectural and surficial morphologies, and will be compared to modern and ancient traces to interpret the tracemaker behavior and paleoenvironmental setting. Distribution of ichnofossils within these units may indicate the effect of lateral variability of pedogenesis, the magnitude and frequency of depositional events, and the amount of moisture within the sediment, as well as the effects of climate change. The paleoclimatic significance of ichnofossils will be determined by comparing the burrow size, occurrence, tiering, and pedogenic significance of ichnofossils in measured sections of stratigraphic units deposited during global warming and cooling episodes. Comparisons will be made between BGA formations to stratigraphically equivalent rocks deposited at low paleolatitudes with previously determined paleoclimatic settings. The objectives of this project are to address two major questions: what differences existed in ichnodiversity, abundance, and tiering in marine and continental deposits between high- and low-paleolatitudes, and was there a dearth of habitat usage in continental deposits during the late Paleozoic and Mesozoic, particularly in fluvial and lacustrine environments compared to the habitat usage in the marine realm at that time? \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis study will enhance the ability to interpret paleoenvironments to the subenvironmental scale, understand the evolution of soil biota and ecosystems at high paleolatitudes, determine the role of organisms in soil formation at high paleolatitudes, explore the effects of climate change on the body size and diversity of organisms in the soil communities, and develop new tools to interpret paleoclimate in high latitudes. There is a strong education component associated with this proposal.", "east": 175.0, "geometry": "POINT(175 -86)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -86.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Hasiotis, Stephen", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Paleoenvironmental and Paleoclimatic Analysis of the Beacon Supergroup, Beardmore Glacier Area, Central Transantarctic Mountains, Antarctica", "uid": "p0000423", "west": 175.0}, {"awards": "1043750 Chen, Jianli", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements", "datasets": [{"dataset_uid": "600159", "doi": "10.15784/600159", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; GRACE; Potential Field; Satellite Data", "people": "Chen, Jianli", "repository": "USAP-DC", "science_program": null, "title": "Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements", "url": "https://www.usap-dc.org/view/dataset/600159"}], "date_created": "Fri, 13 May 2016 00:00:00 GMT", "description": "1043750/Chen This award supports a project to improve the estimate of long-term and inter-annual variability of Antarctic ice sheet mass balance at continental, regional, and catchment scales, using satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) and other geodetic measurements. The work will improve the quantification of long-term mass change rates over Antarctica using GRACE gravity data with a longer record and newer generation(s) of products and will develop advanced numerical forward modeling techniques that can accurately correct leakage effects associated with GRACE data processing, and significantly improve spatial resolution of GRACE mass rate estimates over Antarctica. The work will also contribute to a better understanding of crustal uplift rates due to postglacial rebound (PGR) and present day ice load change over Antarctica via PGR models, GPS measurements, and combined analysis of GRACE and ICESat elevation changes. Inter-annual variations of ice mass over Antarctica will be investigated at continental and catchment scales and connections to regional climate change will be studied. The major deliverables from this study will be improved assessments of ice mass balance for the entire Antarctic ice sheet and potential contribution to global mean sea level rise. The work will also provide estimates of regional ice mass change rates over Antarctica, with a focus along the coast in the Amundsen Sea Embayment, the Peninsula in West Antarctica, and in Wilkes Land and Victoria Land in East Antarctica. Estimates of inter-annual ice mass change over Antarctica at various spatial scales, and assessments of uncertainty of GRACE ice rate estimates and PGR models errors over Antarctica will also be made. The intellectual merits of the proposed investigation include 1) providing improved assessments of Antarctic ice mass balance at different temporal and spatial scales with unprecedented accuracy, an important contribution to broad areas of polar science research; 2) combining high accuracy GPS vertical uplift measurements and PGR models to better quantify long-term crust uplift effects that are not distinguishable from ice mass changes by GRACE; and 3) unifying the work of several investigations at the forefront of quantifying ice sheet and glacier mass balance and crustal uplift based on a variety of modern space geodetic observations. The broader impacts include the fact that the project will actively involve student participation and training, through the support of two graduate students. In addition the project will contribute to general education and public outreach (E/PO) activities and the results from this investigation will help inspire future geoscientists and promote public awareness of significant manifestations of climate change.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e LASER RANGING \u003e GRACE LRR", "is_usap_dc": true, "keywords": "SATELLITES; GRACE; Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Chen, Jianli; Wilson, Clark; Blankenship, Donald D.; Tapley, Byron", "platforms": "Not provided; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e NASA EARTH SYSTEM SCIENCE PATHFINDER \u003e GRACE; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements", "uid": "p0000415", "west": -180.0}, {"awards": "1141326 Rotella, Jay", "bounds_geometry": "POLYGON((163.1 -70.3,163.59 -70.3,164.08 -70.3,164.57 -70.3,165.06 -70.3,165.55 -70.3,166.04 -70.3,166.53 -70.3,167.02 -70.3,167.51 -70.3,168 -70.3,168 -70.98,168 -71.66,168 -72.34,168 -73.02,168 -73.7,168 -74.38,168 -75.06,168 -75.74,168 -76.42,168 -77.1,167.51 -77.1,167.02 -77.1,166.53 -77.1,166.04 -77.1,165.55 -77.1,165.06 -77.1,164.57 -77.1,164.08 -77.1,163.59 -77.1,163.1 -77.1,163.1 -76.42,163.1 -75.74,163.1 -75.06,163.1 -74.38,163.1 -73.7,163.1 -73.02,163.1 -72.34,163.1 -71.66,163.1 -70.98,163.1 -70.3))", "dataset_titles": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "datasets": [{"dataset_uid": "601125", "doi": "10.15784/601125", "keywords": "Antarctica; Biota; Sea Ice", "people": "Rotella, Jay", "repository": "USAP-DC", "science_program": null, "title": "Demographic data for Weddell Seal colonies in Erebus Bay through the 2017 Antarctic field season", "url": "https://www.usap-dc.org/view/dataset/601125"}], "date_created": "Mon, 08 Feb 2016 00:00:00 GMT", "description": "Abstract The Erebus Bay population of Weddell seals in Antarctica?s Ross Sea is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1968. The resulting long-term database, which includes data for 20,586 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The population?s location is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean, one of the few pristine marine environments remaining on the planet, and, in contrast to the Antarctic Peninsula and Arctic, is undergoing a gradual lengthening of the sea-ice season. The work to be continued here capitalizes on (1) long-term data for individual seals and their polar environment; (2) experience collecting and analyzing data from the extensive study population; and (3) recent statistical advances in hierarchical modeling that allow for rigorous treatment of individual heterogeneity (in mark-recapture and body mass data) and inclusion of diverse covariates hypothesized to explain variation in fitness components. Covariates to be considered include traits of individuals and their mothers and environmental conditions throughout life. The study will continue to (1) provide detailed data on known-age individuals to other science projects and (2) educate and mentor the next generation of ecologists through academic and professional training and research experiences.", "east": 168.0, "geometry": "POINT(165.55 -73.7)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.3, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rotella, Jay; Garrott, Robert", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.1, "title": "The Demographic Consequences of Environmental Variability and Individual Heterogeneity in Life-history Tactics of a Long-lived Antarctic Marine Predator", "uid": "p0000299", "west": 163.1}, {"awards": "0948247 Pettit, Erin", "bounds_geometry": "POINT(-123.35 -75.1)", "dataset_titles": null, "datasets": null, "date_created": "Wed, 06 Jan 2016 00:00:00 GMT", "description": "Pettit/0948247\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study of the relationship between fabric and climate for the ice near the EPICA Dome C ice core site, East Antarctica. The work builds on an ongoing study at Siple Dome, West Antarctica and takes advantage of collaborations with European scientists and access to the Dome C borehole to make measurements of sonic velocity. The intellectual merit of the project is that a better understanding of how fabric preserves past climate information can improve models of the ice flow near ice core sites and the interpreta-tion of ice core data (particularly paleo-accumulation), and it may allow us to extract climate information directly from fabric data. In addition, because ice deformation is sensitive to the orientation of crystals, ice flow patterns are sensitive to the fabric. Thus, variations in the fabric between glacial and interglacial ice can affect how ice deforms and how fabric in the ice sheet develops. The Dome C site is particularly important for answering these questions, because the ice core shows evidence of eight glacial cycles, not just one as found at Siple Dome or the Greenland sites. The research will improve the understanding of the proxy relationship between sonic-velocity data and fabric; will help to model the pattern of ice flow caused by the fabric variation between glacial and interglacial time periods using these data, existing ice core chemistry and existing and new thin section data, improved surface strain data, and borehole deformation data; and will help to better understand the positive feedback mechanism that enhances fabric (and corresponding rheological) variability through a focused study of several climate transitions and the associated fabric changes. Borehole compressional-wave sonic-velocity will be measured which will complement the sonic-velocity data that already exist for boreholes in Greenland and West Antarctica. These will be the first sonic-velocity measurements in East Antarctica and the first measurements that extend for more than a single glacial/interglacial transition. The project will ultimately contribute to better interpretation of ice core records for both paleoclimate studies and for ice flow history, both of which connect to the broader questions of the role of ice in the climate system. This project will also strengthen the international collaborations within the paleoclimate and ice sheet modeling communities. This project will partially support a graduate student at the University of Alaska Fairbanks who is currently working on modeling ice including anisotropy and it will support the growth of a young scientist through a Post-Doc position. This Post Doc will gain important experience collaborating with the EPICA scientists in studying the climate-fabric relationship. Erin Pettit is active in field-science education for high school students, under-graduates, teachers, and adults. This project will help support the continued development and enhancement of Girls on Ice a program that encourages young women to explore science and the natural world.", "east": -123.35, "geometry": "POINT(-123.35 -75.1)", "instruments": null, "is_usap_dc": false, "keywords": "LABORATORY; Crystals; Deformation; FIELD INVESTIGATION; Model; Sonic Logger; Ice Flow; Rheology; FIELD SURVEYS; Borehole; Climate; Ice Fabric; Antarctica; Interglacial", "locations": "Antarctica", "north": -75.1, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Pettit, Erin; Hansen, Sharon", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -75.1, "title": "The Relationship between Climate and Ice Rheology at Dome C, East Antarctica", "uid": "p0000708", "west": -123.35}, {"awards": "1039982 Anandakrishnan, Sridhar", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Seismological Data at IRIS (full data link not provided)", "datasets": [{"dataset_uid": "000170", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Seismological Data at IRIS (full data link not provided)", "url": "http://ds.iris.edu/"}], "date_created": "Mon, 23 Nov 2015 00:00:00 GMT", "description": "Intellectual Merit: Knowledge of englacial and subglacial conditions are critical for ice sheet models and predictions of sea-level change. Some of the critical variables that are poorly known but essential for improving flow models and predictions of sea-level change are: basal roughness, subglacial sedimentary and hydrologic conditions, and the temporal and spatial variability of the ice sheet flow field. Seismic reflection and refraction imaging and dense arrays of continuously operating GPS receivers can determine these parameters. The PIs propose to develop a network of wirelessly interconnected geophysical sensors (geoPebble) that will allow glaciologists to carry out these experiments simultaneously. This sensor web will provide a new way of imaging the ice sheet that is not possible with current instruments. With this sensor web, the PIs will extend the range of existing instruments from 2D to 3D, from low resolution to high resolution, but more importantly, all the geophysical measurements will be conducted synchronously. By the end of the proposal period the PIs will produce a network of 150-200 geoPebbles that will be available for NSF-sponsored glaciology research projects. Broader impacts: Improved knowledge of the flow law of ice, the sliding of glaciers and ice streams, and paleoclimate history will contribute to assessments of the potential for abrupt ice-sheet mass change, with consequent sea-level effects and significant societal impacts. This improved modeling ability will be a direct consequence of better knowledge of the physical properties of ice sheets, which this project will facilitate. The development effort will be integrated with the undergraduate education program via the capstone design classes in EE and the senior thesis requirement in Geoscience. The PIs will also form a cohort of first-year and sophomore students who will work in their labs from the beginning of the project to develop specifications through the commissioning of the network.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anandakrishnan, Sridhar; Bilen, Sven; Urbina, Julio", "platforms": "Not provided", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -90.0, "title": "MRI: Development of a Wirelessly-Connected Network of Seismometers and GPS Instruments for Polar and Geophysical Research", "uid": "p0000405", "west": -180.0}, {"awards": "0944653 Forster, Richard", "bounds_geometry": "POLYGON((-119.4 -78.1,-118.46000000000001 -78.1,-117.52000000000001 -78.1,-116.58 -78.1,-115.64 -78.1,-114.7 -78.1,-113.76 -78.1,-112.82000000000001 -78.1,-111.88 -78.1,-110.94 -78.1,-110 -78.1,-110 -78.28999999999999,-110 -78.47999999999999,-110 -78.67,-110 -78.86,-110 -79.05,-110 -79.24,-110 -79.42999999999999,-110 -79.62,-110 -79.81,-110 -80,-110.94 -80,-111.88 -80,-112.82000000000001 -80,-113.76 -80,-114.7 -80,-115.64 -80,-116.58 -80,-117.52000000000001 -80,-118.46000000000001 -80,-119.4 -80,-119.4 -79.81,-119.4 -79.62,-119.4 -79.42999999999999,-119.4 -79.24,-119.4 -79.05,-119.4 -78.86,-119.4 -78.67,-119.4 -78.47999999999999,-119.4 -78.28999999999999,-119.4 -78.1))", "dataset_titles": "Annual Satellite Era Accumulation Patterns Over WAIS Divide: A Study Using Shallow Ice Cores, Near-Surface Radars and Satellites", "datasets": [{"dataset_uid": "600146", "doi": "10.15784/600146", "keywords": "Airborne Radar; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; WAIS Divide; WAIS Divide Ice Core", "people": "Forster, Richard", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Annual Satellite Era Accumulation Patterns Over WAIS Divide: A Study Using Shallow Ice Cores, Near-Surface Radars and Satellites", "url": "https://www.usap-dc.org/view/dataset/600146"}], "date_created": "Fri, 20 Nov 2015 00:00:00 GMT", "description": "This award supports a project to broaden the knowledge of annual accumulation patterns over the West Antarctic Ice Sheet by processing existing near-surface radar data taken on the US ITASE traverse in 2000 and by gathering and validating new ultra/super-high-frequency (UHF) radar images of near surface layers (to depths of ~15 m), expanding abilities to monitor recent annual accumulation patterns from point source ice cores to radar lines. Shallow (15 m) ice cores will be collected in conjunction with UHF radar images to confirm that radar echoed returns correspond with annual layers, and/or sub-annual density changes in the near-surface snow, as determined from ice core stable isotopes. This project will additionally improve accumulation monitoring from space-borne instruments by comparing the spatial-radar-derived-annual accumulation time series to the passive microwave time series dating back over 3 decades and covering most of Antarctica. The intellectual merit of this project is that mapping the spatial and temporal variations in accumulation rates over the Antarctic ice sheet is essential for understanding ice sheet responses to climate forcing. Antarctic precipitation rate is projected to increase up to 20% in the coming century from the predicted warming. Accumulation is a key component for determining ice sheet mass balance and, hence, sea level rise, yet our ability to measure annual accumulation variability over the past 5 decades (satellite era) is mostly limited to point-source ice cores. Developing a radar and ice core derived annual accumulation dataset will provide validation data for space-born remote sensing algorithms, climate models and, additionally, establish accumulation trends. The broader impacts of the project are that it will advance discovery and understanding within the climatology, glaciology and remote sensing communities by verifying the use of UHF radars to monitor annual layers as determined by visual, chemical and isotopic analysis from corresponding shallow ice cores and will provide a dataset of annual to near-annual accumulation measurements over the past ~5 decades across WAIS divide from existing radar data and proposed radar data. By determining if temporal changes in the passive microwave signal are correlated with temporal changes in accumulation will help assess the utility of passive microwave remote sensing to monitor accumulation rates over ice sheets for future decades. The project will promote teaching, training and learning, and increase representation of underrepresented groups by becoming involved in the NASA History of Winter project and Thermochron Mission and by providing K-12 teachers with training to monitor snow accumulation and temperature here in the US, linking polar research to the student?s backyard. The project will train both undergraduate and graduate students in polar research and will encouraging young investigators to become involved in careers in science. In particular, two REU students will participate in original research projects as part of this larger project, from development of a hypothesis to presentation and publication of the results. The support of a new, young woman scientist will help to increase gender diversity in polar research.", "east": -110.0, "geometry": "POINT(-114.7 -79.05)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.1, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Forster, Richard", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -80.0, "title": "Collaborative Research: Annual satellite era accumulation patterns over WAIS Divide: A study using shallow ice cores, near-surface radars and satellites", "uid": "p0000079", "west": -119.4}, {"awards": "1043780 Aydin, Murat", "bounds_geometry": null, "dataset_titles": "Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core; Ultra-trace Measurements in the WAIS Divide 06A Ice Core", "datasets": [{"dataset_uid": "609659", "doi": "10.7265/N5CV4FPK", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Ultra-trace Measurements in the WAIS Divide 06A Ice Core", "url": "https://www.usap-dc.org/view/dataset/609659"}, {"dataset_uid": "601361", "doi": "10.15784/601361", "keywords": "Antarctica; Carbonyl Sulfide; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/601361"}], "date_created": "Tue, 27 Oct 2015 00:00:00 GMT", "description": "Aydin/1043780 This award supports the analysis of the trace gas carbonyl sulfide (COS) in a deep ice core from West Antarctic Ice Sheet Divide (WAIS-D), Antarctica. COS is the most abundant sulfur gas in the troposphere and a precursor of stratospheric sulfate. It has a large terrestrial COS sink that is tightly coupled to the photosynthetic uptake of atmospheric carbon dioxide (CO2). The primary goal of this project is to develop high a resolution Holocene record of COS from the WAIS-D 06A ice core. The main objectives are 1) to assess the natural variability of COS and the extent to which its atmospheric variability was influenced by climate variability, and 2) to examine the relationship between changes in atmospheric COS and CO2. This project also includes low-resolution sampling and analysis of COS from 10,000-30,000 yrs BP, covering the transition from the Last Glacial Maximum into the early Holocene. The goal of this work is to assess the stability of COS in ice core air over long time scales and to establish the COS levels during the last glacial maximum and the magnitude of the change between glacial and interglacial conditions. The results of this work will be disseminated via peer-review publications and will contribute to environmental assessments such as the WMO Stratospheric Ozone Assessment and IPCC Climate Assessment. This project will support a PhD student and undergraduate researcher in the Department of Earth System Science at the University of California, Irvine, and will create summer research opportunities for undergraduates from non-research active Universities.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ethane; LABORATORY; N-Butane; Carbonyl Sulfide; Propane; Methyl Bromide; Methyl Chloride; Carbon Disulfide", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat; Saltzman, Eric", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Carbonyl Sulfide Measurements in the Deep West Antarctic Ice Sheet Divide Ice Core", "uid": "p0000055", "west": null}, {"awards": "0632282 Jacobs, Stanley", "bounds_geometry": "POLYGON((-129.6 -54.2,-124.44 -54.2,-119.28 -54.2,-114.12 -54.2,-108.96 -54.2,-103.8 -54.2,-98.64 -54.2,-93.48 -54.2,-88.32 -54.2,-83.16 -54.2,-78 -54.2,-78 -56.29,-78 -58.38,-78 -60.47,-78 -62.56,-78 -64.65,-78 -66.74,-78 -68.83,-78 -70.92,-78 -73.01,-78 -75.1,-83.16 -75.1,-88.32 -75.1,-93.48 -75.1,-98.64 -75.1,-103.8 -75.1,-108.96 -75.1,-114.12 -75.1,-119.28 -75.1,-124.44 -75.1,-129.6 -75.1,-129.6 -73.01,-129.6 -70.92,-129.6 -68.83,-129.6 -66.74,-129.6 -64.65,-129.6 -62.56,-129.6 -60.47,-129.6 -58.38,-129.6 -56.29,-129.6 -54.2))", "dataset_titles": "Amundsen Sea Continental Shelf Mooring Data (2006-2007); Calibrated Hydrographic Data acquired with a LADCP from the Amundsen Sea acquired during the Nathaniel B. Palmer expedition NBP0901; NBP07-09 cruise data; NBP07-09 processed CTD data; NBP09-01 cruise data; NBP09-01 processed CTD data; Processed Temperature, Salinity, and Current Measurement Data from the Amundsen Sea acquired during the Nathaniel B. Palmer expedition NBP0901", "datasets": [{"dataset_uid": "000127", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP07-09 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP0709"}, {"dataset_uid": "601809", "doi": "10.15784/601809", "keywords": "Amundsen Sea; Antarctica; Cryosphere; Mooring; Ocean Currents; Pressure; Salinity; Temperature", "people": "Giulivi, Claudia F.; Jacobs, Stanley", "repository": "USAP-DC", "science_program": null, "title": "Amundsen Sea Continental Shelf Mooring Data (2006-2007)", "url": "https://www.usap-dc.org/view/dataset/601809"}, {"dataset_uid": "000128", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "NBP07-09 processed CTD data", "url": "http://accession.nodc.noaa.gov/0120761"}, {"dataset_uid": "000129", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP09-01 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP0901"}, {"dataset_uid": "000130", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "NBP09-01 processed CTD data", "url": "http://accession.nodc.noaa.gov/0071179"}, {"dataset_uid": "601350", "doi": null, "keywords": "Amundsen Sea; Antarctic; Antarctica; CTD; CTD Data; Current Measurements; NBP0901; Oceans; Physical Oceanography; Pine Island Bay; Pine Island Glacier; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Jacobs, Stanley; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed Temperature, Salinity, and Current Measurement Data from the Amundsen Sea acquired during the Nathaniel B. Palmer expedition NBP0901", "url": "https://www.usap-dc.org/view/dataset/601350"}, {"dataset_uid": "601349", "doi": null, "keywords": "Amundsen Sea; Antarctica; Current Measurements; LADCP; NBP0901; Oceans; Physical Oceanography; Pine Island Bay; R/v Nathaniel B. Palmer; Southern Ocean", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Calibrated Hydrographic Data acquired with a LADCP from the Amundsen Sea acquired during the Nathaniel B. Palmer expedition NBP0901", "url": "https://www.usap-dc.org/view/dataset/601349"}], "date_created": "Fri, 25 Sep 2015 00:00:00 GMT", "description": "The Office of Polar Programs, Antarctic Science Division, Ocean \u0026 Climate Systems Program has made this award to support a multidisciplinary effort to study the upwelling of relatively warm deep water onto the Amundsen Sea continental shelf and how it relates to atmospheric forcing and bottom bathymetry and how the warm waters interact with both glacial and sea ice. This study constitutes a contribution of a coordinated research effort in the region known as the Amundsen Sea Embayment Project or ASEP. Previous work by the PI and others has shown that the West Antarctic Ice Sheet has been found to be melting faster, perhaps by orders of magnitude, than ice sheets elsewhere around Antarctica, excluding those on the Peninsula. Submarine channels that incise the continental shelf are thought to provide fairly direct access of relatively warm circum polar deep water to the cavity under the floating extension of the ice shelf. Interactions with sea ice en route can modify the upwelled waters. The proposed investigations build on previous efforts by the PI and colleagues to use hydrographic measurements to put quantitative bounds on the rate of glacial ice melt by relatively warm seawater. \u003cbr/\u003eThe region can be quite difficult to access due to sea ice conditions and previous hydrographic measurements have been restricted to the austral summer time frame. In this project it was proposed to obtain the first austral spring hydrographic data via CTD casts and XBT drops (September-October 2007) as part of a separately funded cruise (PI Steve Ackley) the primary focus of which is sea-ice conditions to be studied while the RV Nathanial B Palmer (RV NBP) drifts in the ice pack. This includes opportunistic sampling for pCO2 and TCO2. A dedicated cruise in austral summer 2009 will follow this opportunity. The principal objectives of the dedicated field program are to deploy a set of moorings with which to characterize temporal variability in warm water intrusions onto the shelf and to conduct repeat hydrographic surveying and swath mapping in targeted areas, ice conditions permitting. Automatic weather stations are to be deployed in concert with the program, sea-ice observations will be undertaken from the vessel and the marine cavity beneath the Pine Island may be explored pending availability of the British autonomous underwater vehicle Autosub 3. These combined ocean-sea ice-atmosphere observations are aimed at a range of model validations. A well-defined plan for making data available as well as archiving in a timely fashion should facilitate a variety of modeling efforts and so extend the value of the spatially limited observations. \u003cbr/\u003eBroader impacts: This project is relevant to an International Polar Year research emphasis on ice sheet dynamics focusing in particular on the seaward ocean-ice sheet interactions. Such interactions must be clarified for understanding the potential for sea level rise by melt of the West Antarctic ice Sheet. The project entails substantive international partnerships (British Antarctic Survey and Alfred Wegner Institute) and complements other Amundsen Sea Embayment Project proposals covering other elements of ice sheet dynamics. The proposal includes partial support for 2 graduate students and 2 post docs. Participants from the Antarctic Artists and Writers program are to take part in the cruise and so aid in outreach. In addition, the project is to be represented in the Lamont-Doherty annual open house.", "east": -78.0, "geometry": "POINT(-103.8 -64.65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": true, "keywords": "Not provided; R/V NBP", "locations": null, "north": -54.2, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jacobs, Stanley; Hellmer, Hartmut; Jenkins, Adrian", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "NCEI; R2R; USAP-DC", "science_programs": null, "south": -75.1, "title": "Collaborative International Research: Amundsen Sea Influence on West Antarctic Ice Sheet Stability and Sea Level Rise - IPY/ASEP", "uid": "p0000332", "west": -129.6}, {"awards": "1245821 Brook, Edward J.; 1246148 Severinghaus, Jeffrey; 1245659 Petrenko, Vasilii", "bounds_geometry": "POINT(162.167 -77.733)", "dataset_titles": "Gas and Dust Measurements for Taylor Glacier and Taylor Dome Ice Cores; Last Interglacial Mean Ocean Temperature; Mean Ocean Temperature in Marine Isotope Stage 4; Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation; N2O Concentration and Isotope Data for 74-59 ka from Taylor Glacier, Antarctica; Taylor Glacier CO2 Isotope Data 74-59 kyr; Taylor Glacier Noble Gases - Younger Dryas; The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "datasets": [{"dataset_uid": "601176", "doi": "10.15784/601176", "keywords": "Antarctica; CO2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Methane; Noble Gas; Noble Gas Isotopes; Snow/ice; Snow/Ice; Taylor Glacier; Younger Dryas", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Glacier Noble Gases - Younger Dryas", "url": "https://www.usap-dc.org/view/dataset/601176"}, {"dataset_uid": "601198", "doi": "10.15784/601198", "keywords": "Antarctica; Blue Ice; Chemistry:ice; Chemistry:Ice; CO2; Dust; Gas; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Mass Spectrometer; Methane; Nitrogen Isotopes; Oxygen Isotope; Paleoclimate; Snow/ice; Snow/Ice; Taylor Dome; Taylor Dome Ice Core", "people": "Barker, Stephen; Shackleton, Sarah; Dyonisius, Michael; Menking, James; Petrenko, Vasilii; McConnell, Joseph; Brook, Edward J.; Rhodes, Rachel; Bauska, Thomas; Baggenstos, Daniel; Severinghaus, Jeffrey P.; Marcott, Shaun", "repository": "USAP-DC", "science_program": null, "title": "Gas and Dust Measurements for Taylor Glacier and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/601198"}, {"dataset_uid": "600163", "doi": "10.15784/600163", "keywords": "Antarctica; Atmosphere; Geochemistry; Ice Core Records; Isotope; Paleoclimate; Taylor Glacier; Transantarctic Mountains", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": null, "title": "The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "url": "https://www.usap-dc.org/view/dataset/600163"}, {"dataset_uid": "601398", "doi": "10.15784/601398", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Gas Records; Ice Core Records; Marine Isotope Stage 4; MIS 4; Nitrous Oxide; Pleistocene; Taylor Dome Ice Core; Taylor Glacier", "people": "Menking, James; Petrenko, Vasilii; Severinghaus, Jeffrey P.; Dyonisius, Michael; Shackleton, Sarah; Schilt, Adrian; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "N2O Concentration and Isotope Data for 74-59 ka from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601398"}, {"dataset_uid": "601218", "doi": "10.15784/601218", "keywords": "Antarctica; Carbon-14; Carbon Dioxide; Chemistry:ice; Chemistry:Ice; CO2; Dome C Ice Core; Epica; Epica Dome C; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; Isotope Data; Last Interglacial; Mass Spectrometer; Mass Spectrometry; Methane; Oxygen; Oxygen Isotope; Paleotemperature; Pleistocene; Snow/ice; Snow/Ice; Taylor Dome Ice Core; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "Last Interglacial Mean Ocean Temperature", "url": "https://www.usap-dc.org/view/dataset/601218"}, {"dataset_uid": "601218", "doi": "10.15784/601218", "keywords": "Antarctica; Carbon-14; Carbon Dioxide; Chemistry:ice; Chemistry:Ice; CO2; Dome C Ice Core; Epica; Epica Dome C; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; Isotope Data; Last Interglacial; Mass Spectrometer; Mass Spectrometry; Methane; Oxygen; Oxygen Isotope; Paleotemperature; Pleistocene; Snow/ice; Snow/Ice; Taylor Dome Ice Core; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Last Interglacial Mean Ocean Temperature", "url": "https://www.usap-dc.org/view/dataset/601218"}, {"dataset_uid": "601600", "doi": "10.15784/601600", "keywords": "Antarctica; Taylor Glacier", "people": "Menking, James; Shackleton, Sarah; Bauska, Thomas; Buffen, Aron; Brook, Edward J.; Barker, Stephen; Severinghaus, Jeffrey P.; Dyonisius, Michael; Petrenko, Vasilii; Menking, Andy", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier CO2 Isotope Data 74-59 kyr", "url": "https://www.usap-dc.org/view/dataset/601600"}, {"dataset_uid": "601260", "doi": "10.15784/601260", "keywords": "Antarctica; Carbon-14; Cosmogenic; Ice Core; Methane", "people": "Dyonisius, Michael; Petrenko, Vasilii", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation", "url": "https://www.usap-dc.org/view/dataset/601260"}, {"dataset_uid": "601415", "doi": "10.15784/601415", "keywords": "Antarctica; Glaciology; Ice Core Data; Ice Core Records; Paleoclimate; Paleotemperature; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Mean Ocean Temperature in Marine Isotope Stage 4", "url": "https://www.usap-dc.org/view/dataset/601415"}], "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "1245659/Petrenko This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, \u0026#948;18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, \u0026#948;13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of \u0026#948;13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.", "east": 162.167, "geometry": "POINT(162.167 -77.733)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Not provided; USAP-DC; FIELD INVESTIGATION; Stratigraphy; FIELD SURVEYS; Antarctica; Paleoenvironment; Methane; Ice Core; Carbon Dioxide; FIXED OBSERVATION STATIONS; Stable Isotopes; Ablation Zone; Taylor Glacier; Nitrous Oxide; USA/NSF; LABORATORY; AMD; Cosmogenic; Amd/Us", "locations": "Taylor Glacier; Antarctica", "north": -77.733, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Petrenko, Vasilii; Brook, Edward J.; Severinghaus, Jeffrey P.; PETRENKO, VASILLI", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.733, "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "uid": "p0000283", "west": 162.167}, {"awards": "1141890 Huber, Bruce", "bounds_geometry": "POLYGON((-62.176502 -57.913998,-61.4764715 -57.913998,-60.776441 -57.913998,-60.0764105 -57.913998,-59.37638 -57.913998,-58.6763495 -57.913998,-57.976319 -57.913998,-57.2762885 -57.913998,-56.576258 -57.913998,-55.8762275 -57.913998,-55.176197 -57.913998,-55.176197 -58.6469082,-55.176197 -59.3798184,-55.176197 -60.1127286,-55.176197 -60.8456388,-55.176197 -61.578549,-55.176197 -62.3114592,-55.176197 -63.0443694,-55.176197 -63.7772796,-55.176197 -64.5101898,-55.176197 -65.2431,-55.8762275 -65.2431,-56.576258 -65.2431,-57.2762885 -65.2431,-57.976319 -65.2431,-58.6763495 -65.2431,-59.37638 -65.2431,-60.0764105 -65.2431,-60.776441 -65.2431,-61.4764715 -65.2431,-62.176502 -65.2431,-62.176502 -64.5101898,-62.176502 -63.7772796,-62.176502 -63.0443694,-62.176502 -62.3114592,-62.176502 -61.578549,-62.176502 -60.8456388,-62.176502 -60.1127286,-62.176502 -59.3798184,-62.176502 -58.6469082,-62.176502 -57.913998))", "dataset_titles": "Expedition Data of NBP1203; Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "datasets": [{"dataset_uid": "001438", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1203", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}, {"dataset_uid": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}], "date_created": "Wed, 17 Jun 2015 00:00:00 GMT", "description": "Time series data, from ocean moorings, on key aspects of evolving ocean properties are of considerable importance in assessing the condition of the ocean system. They are needed, for example, their understand how the oceans are warming, and how they continue to uptake greenhouse gases such as CO2. The Cape Adare Long Term Mooring (CALM) program goal was to observe the bottom water export from the Ross Sea to the deep ocean. To accomplish this two instrumented moorings were set on the continental slope off Cape Adare (western Ross Sea, Antarctica), positioned to capture the export of Antarctic Bottom Water (AABW), some of the coldest and densest water found in the global ocean. Data records for the moorings spans over some four years in this very remote part of the ocean. The CALM analysis will address some specific objectives: ? Characterize the temperature, salinity and current variability associated with the Ross Sea AABW export. ? Examine the linkages between observed variability to regional tides, atmosphere and sea ice forcing. ? Relate the Ross Sea AABW export fluctuations to the larger scale climate system dynamics, such as ENSO and SAM, and to AABW formation along other margins of Antarctica, e.g. the Weddell Sea", "east": -55.176197, "geometry": "POINT(-58.6763495 -61.578549)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -57.913998, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Huber, Bruce; Vernet, Maria", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -65.2431, "title": "Cape Adare Long Term Moorings (CALM): Analysis Phase", "uid": "p0000495", "west": -62.176502}, {"awards": "1043217 Zagorodnov, Victor", "bounds_geometry": null, "dataset_titles": "Fiber-Optic Distributed Temperature Sensing at Windless Bight", "datasets": [{"dataset_uid": "609604", "doi": "10.7265/N5V122QS", "keywords": "Antarctica; Ice Shelf; McMurdo Sound; Mooring; Oceans; Physical Oceanography; Ross Ice Shelf; Southern Ocean", "people": "Tyler, Scott W.; Holland, David; Zagorodnov, Victor", "repository": "USAP-DC", "science_program": null, "title": "Fiber-Optic Distributed Temperature Sensing at Windless Bight", "url": "https://www.usap-dc.org/view/dataset/609604"}], "date_created": "Tue, 05 May 2015 00:00:00 GMT", "description": "Abstract Researchers will explore the use of a distributed temperature sensing monitoring system (DTS), using fiber-optical (FO) technology, as the basis of a sustainable, sub-ice cavity sensing array. FO cable systems, such as may be deployed through a hot-water drilled hole through an ice shelf, passing through the underlying cavity to the sea floor, are capable of measuring temperatures down fiber at 1 meter intervals, and at time frequencies as high as 15 seconds. DTS FO systems operate via optical time domain reflectometry along the fiber waveguide using inelastic backscatter of coherent laser light as a probe beam in the FO environment. The introduction of new technologies to the harsh environmental conditions of the Antarctic are often associated with high risk. However, the potential rewards of this approach (e.g. multiyear capability, minimal submerged mechanical or electrical components that may fail, relative simplicity of deployment and measurement principle, yet yielding distributed real time and spatial observation) are attractive enough to conduct a pilot project at a field-ready location (McMurdo). Current indications are that the instability of some of the world\u0027s largest ice sheets located around the Antarctic and Greenland may be caused by the presence of warming, deep ocean waters, shoaling over continental shelves, and melting the underside of floating ice shelves. Additional knowledge of the temporal and spatial variability of the temperature fields underneath terminal ice shelves, such as those draining the West Antarctic Ice Sheet, are needed to accurately project future global climate effects on ice-shelf ocean interactions, and in order to inform societal and technological aspects of adaption to changing sea-level.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e TEMPERATURE LOGGERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "GROUND STATIONS; Not provided; Conservative Temperature; MOORINGS; Ice Shelf Temperature; Ocean Temperature", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Zagorodnov, Victor; Holland, David; Tyler, Scott W.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e MOORINGS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Application of Distributed Temperature Sensors (DTS) for Antarctic Ice Shelves and Cavities", "uid": "p0000183", "west": null}, {"awards": "0944727 Arrigo, Kevin", "bounds_geometry": "POLYGON((-118.3 -71.6,-117.57 -71.6,-116.84 -71.6,-116.11 -71.6,-115.38 -71.6,-114.65 -71.6,-113.92 -71.6,-113.19 -71.6,-112.46 -71.6,-111.73 -71.6,-111 -71.6,-111 -71.86,-111 -72.12,-111 -72.38,-111 -72.64,-111 -72.9,-111 -73.16,-111 -73.42,-111 -73.68,-111 -73.94,-111 -74.2,-111.73 -74.2,-112.46 -74.2,-113.19 -74.2,-113.92 -74.2,-114.65 -74.2,-115.38 -74.2,-116.11 -74.2,-116.84 -74.2,-117.57 -74.2,-118.3 -74.2,-118.3 -73.94,-118.3 -73.68,-118.3 -73.42,-118.3 -73.16,-118.3 -72.9,-118.3 -72.64,-118.3 -72.38,-118.3 -72.12,-118.3 -71.86,-118.3 -71.6))", "dataset_titles": "Dataset: Chlorophyll a", "datasets": [{"dataset_uid": "000172", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Chlorophyll a", "url": "http://www.bco-dmo.org/dataset/546372"}], "date_created": "Fri, 30 Jan 2015 00:00:00 GMT", "description": "ASPIRE is an NSF-funded project that will examine the ecology of the Amundsen Sea during the Austral summer of 2010. ASPIRE includes an international team of trace metal and carbon chemists, phytoplankton physiologists, microbial and zooplankton ecologists, and physical oceanographers, that will investigate why and how the Amundsen Sea Polynya is so much more productive than other polynyas and whether interannual variability can provide insight to climate-sensitive mechanisms driving carbon fluxes. This project will compliment the existing ASPIRE effort by using 1) experimental manipulations to understand photoacclimation of the dominant phytoplankton taxa under conditions of varying light and trace metal abundance, 2) nutrient addition bioassays to determine the importance of trace metal versus nitrogen limitation of phytoplankton growth, and 3) a numerical ecosystem model to understand the importance of differences in mixing regime, flow field, and Fe sources in controlling phytoplankton bloom dynamics and community composition in this unusually productive polynya system. The research strategy will integrate satellite remote sensing, field-based experimental manipulations, and numerical modeling. Outreach and education include participation in Stanford\u0027s Summer Program for Professional Development for Science Teachers, Stanford\u0027s School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center. Undergraduate participation and training will include support for both graduate students and undergraduate assistants.", "east": -111.0, "geometry": "POINT(-114.65 -72.9)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -71.6, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin", "platforms": "Not provided", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -74.2, "title": "ASPIRE: Amundsen Sea Polynya International Research Expedition", "uid": "p0000348", "west": -118.3}, {"awards": "0635437 Donohue, Kathleen; 0636493 Chereskin, Teresa", "bounds_geometry": "POLYGON((-65.09 -54.96,-64.618 -54.96,-64.146 -54.96,-63.674 -54.96,-63.202 -54.96,-62.73 -54.96,-62.258 -54.96,-61.786 -54.96,-61.314 -54.96,-60.842 -54.96,-60.37 -54.96,-60.37 -55.661,-60.37 -56.362,-60.37 -57.063,-60.37 -57.764,-60.37 -58.465,-60.37 -59.166,-60.37 -59.867,-60.37 -60.568,-60.37 -61.269,-60.37 -61.97,-60.842 -61.97,-61.314 -61.97,-61.786 -61.97,-62.258 -61.97,-62.73 -61.97,-63.202 -61.97,-63.674 -61.97,-64.146 -61.97,-64.618 -61.97,-65.09 -61.97,-65.09 -61.269,-65.09 -60.568,-65.09 -59.867,-65.09 -59.166,-65.09 -58.465,-65.09 -57.764,-65.09 -57.063,-65.09 -56.362,-65.09 -55.661,-65.09 -54.96))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001522", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1107"}, {"dataset_uid": "001476", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0908"}, {"dataset_uid": "001521", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0710"}, {"dataset_uid": "001490", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0812"}, {"dataset_uid": "001463", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1004"}], "date_created": "Tue, 12 Aug 2014 00:00:00 GMT", "description": "The proposed work is a multi-year study of the transport of water through Drake Passage by the Antarctic Circumpolar Current (ACC). Drake Passage acts as a chokepoint that is not only well suited geographically for measuring the time-varying transport, but observations and computer models suggest that dynamical balances which control the transport are particularly effective here. An array of Current Meters and Pressure-recording Inverted Echo Sounders (CPIES) will be set out for a period of 4 years to quantify the transport and dynamics of the Antarctic Circumpolar Current. Data will be collected annually by acoustic telemetry, leaving the instruments undisturbed until recovered at the end of the project. \u003cbr/\u003e\u003cbr/\u003eThe Southern Ocean is believed to be especially sensitive to climate change, responding to winds that have increased over the past thirty years, and warming significantly more than the global ocean over the past fifty years. The proposed observations will resolve the seasonal and interannual variability of the total ACC transport, as well as its vertical and lateral structure. Although not submitted specifically to the International Polar Year (IPY) Program Solicitation, the proposed project contributes to the IPY goal of understanding environmental change in polar regions and represents a pulse of activity in the IPY time frame that will extend the legacy of the IPY. The data and findings will be reported to publicly accessible archives and submitted for publication in the scientific literature. It is a scientific collaboration between the University of California, San Diego, and the University of Rhode Island.", "east": -60.37, "geometry": "POINT(-62.73 -58.465)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -54.96, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Chereskin, Teresa; Donohue, Kathleen; Watts, D.; Tracey, Karen; Kennelly, Maureen", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -61.97, "title": "Collaborative Research: Dynamics and Transport of the Antarctic Circumpolar Current in Drake Passage", "uid": "p0000543", "west": -65.09}, {"awards": "0538672 Palo, Scott", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 31 Jul 2014 00:00:00 GMT", "description": "The mesosphere and lower thermosphere (MLT), at an altitude between 80 and 120 km above the Earth\u0027s surface, is a highly dynamic region that couples the lower terrestrial atmosphere (troposphere and stratosphere) with the upper atmosphere near-Earth space environment (thermosphere and ionosphere). Of particular importance in this region are both the upward propagating thermally forced atmospheric tides and global scale planetary waves. Both of these phenomena transport heat and momentum from the lower atmosphere into the upper atmosphere. Studies in recent years have indicated that the Arctic and Antarctic MLT possess a rich spectrum waves and may be more sensitive to global change than the lower atmosphere. The primary goal of this research is to observe, quantify, model, and further understand the spatial-temporal structure and variability of the MLT circulation above Antarctica and its commonalities with the Arctic. A secondary goal is to quantify and understand the deposition of mass into the upper atmosphere through the ablation of meteors and the resulting effect on local and regional aeronomic processes. This includes the effect of meteor flux, temperature and dynamics on the seasonal distribution of sodium over the South Pole. Meteor radar was installed at the South Pole Amundsen-Scott station and has been running continuously since January 2002. A new sodium nightglow imager will be installed at the South Pole to infer the sodium abundance in the MLT. Observations from this instrument will be combined with the South Pole Fabry-Perot interferometer temperature measurements and the meteor radar wind and meteor flux measurements to improve our understanding of the sodium chemistry and dynamics. These observations will be interpreted using sophisticated numerical models and interpreted in conjunction with Arctic measurements along with current linear and nonlinear atmospheric models to advance the current understanding of processes important to the MLT region. This research also contributes to the training and education of the graduate and undergraduate students, a postdoc and early career tenure track faculty.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Palo, Scott; Avery, James; Avery, Susan", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Studies of the Antarctic Mesosphere and Lower Thermosphere", "uid": "p0000491", "west": -180.0}, {"awards": "0838996 Hollibaugh, James", "bounds_geometry": "POLYGON((-79 -63,-77.5 -63,-76 -63,-74.5 -63,-73 -63,-71.5 -63,-70 -63,-68.5 -63,-67 -63,-65.5 -63,-64 -63,-64 -63.8,-64 -64.6,-64 -65.4,-64 -66.2,-64 -67,-64 -67.8,-64 -68.6,-64 -69.4,-64 -70.2,-64 -71,-65.5 -71,-67 -71,-68.5 -71,-70 -71,-71.5 -71,-73 -71,-74.5 -71,-76 -71,-77.5 -71,-79 -71,-79 -70.2,-79 -69.4,-79 -68.6,-79 -67.8,-79 -67,-79 -66.2,-79 -65.4,-79 -64.6,-79 -63.8,-79 -63))", "dataset_titles": "Ammonia Oxidation Versus Heterotrophy in Crenarchaeota Populations from Marine Environments West of the Antarctic Peninsula; Expedition data of LMG1006", "datasets": [{"dataset_uid": "002722", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1006", "url": "https://www.rvdata.us/search/cruise/LMG1006"}, {"dataset_uid": "600105", "doi": "10.15784/600105", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; LMG1006; LMG1101; LTER Palmer Station; Oceans; Southern Ocean", "people": "Hollibaugh, James T.", "repository": "USAP-DC", "science_program": null, "title": "Ammonia Oxidation Versus Heterotrophy in Crenarchaeota Populations from Marine Environments West of the Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/600105"}], "date_created": "Thu, 13 Mar 2014 00:00:00 GMT", "description": "Ammonia oxidation is the first step in the conversion of regenerated nitrogen to dinitrogen gas, a 3-step pathway mediated by 3 distinct guilds of bacteria and archaea. Ammonia oxidation and the overall process of nitrification-denitrification have received relatively little attention in polar oceans where the effects of climate change on biogeochemical rates are likely to be pronounced. Previous work on Ammonia Oxidizing Archaea (AOA) in the Palmer LTER study area West of the Antarctic Peninsula (WAP), has suggested strong vertical segregation of crenarchaeote metabolism, with the \"winter water\" (WW, ~50-100 m depth range) dominated by non-AOA crenarchaeotes, while Crenarchaeota populations in the \"circumpolar deep water\" (CDW), which lies immediately below the winter water (150-3500 m), are dominated by AOA. Analysis of a limited number of samples from the Arctic Ocean did not reveal a comparable vertical segregation of AOA, and suggested that AOA and Crenarchaeota abundance is much lower there than in the Antarctic. These findings led to 3 hypotheses that will be tested in this project: 1) the apparent low abundance of Crenarchaeota and AOA in Arctic Ocean samples may be due to spatial or temporal variability in populations; 2) the WW population of Crenarchaeota in the WAP is dominated by a heterotroph; 3) the WW population of Crenarchaeota in the WAP \"grows in\" during spring and summer after this water mass forms. \u003cbr/\u003e\u003cbr/\u003eThe study will contribute substantially to understanding an important aspect of the nitrogen cycle in the Palmer LTER (Long Term Ecological Research) study area by providing insights into the ecology and physiology of AOA. The natural segregation of crenarchaeote phenotypes in waters of the WAP, coupled with metagenomic studies in progress in the same area by others (A. Murray, H. Ducklow), offers the possibility of major breakthroughs in understanding of the metabolic capabilities of these organisms. This knowledge is needed to model how water column nitrification will respond to changes in polar ecosystems accompanying global climate change. The Principal Investigator will participate fully in the education and outreach efforts of the Palmer LTER, including making highlights of our findings available for posting to their project web site and participating in outreach (for example, Schoolyard LTER). The research also will involve undergraduates (including the field work if possible) and will support high school interns in the P.I.\u0027s laboratory over the summer.", "east": -64.0, "geometry": "POINT(-71.5 -67)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "R/V LMG", "locations": null, "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hollibaugh, James T.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": "LTER", "south": -71.0, "title": "Ammonia Oxidation Versus Heterotrophy in Crenarchaeota Populations from Marine Environments West of the Antarctic Peninsula", "uid": "p0000359", "west": -79.0}, {"awards": "1232962 Ledwell, James", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1310A", "datasets": [{"dataset_uid": "002658", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1310A", "url": "https://www.rvdata.us/search/cruise/NBP1310A"}], "date_created": "Fri, 07 Feb 2014 00:00:00 GMT", "description": "Intellectual Merit: The Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) is a study of ocean mixing in the Antarctic Circumpolar Current (ACC) which runs west to east all around the continent of Antarctica, south of the other continents. This current system is somewhat of a barrier to transport of heat, carbon dioxide and other important ocean constituents between the far south and the rest of the ocean, and mixing processes play an important role in those transports. DIMES is a multi-investigator cooperative project, led by physical oceanographers in the U.S. and in the U.K. A passive tracer and an array of sub-surface floats were deployed early in 2009 more than 2000 km west of Drake Passage on a surface of constant density about 1500 m deep between the Sub Antarctic Front and the Polar Front of the ACC. In early 2010 a U.S. led research cruise sampled the tracer, turbulence levels, and the velocity and density profiles that govern the generation of that turbulence, and additional U.K. led research cruises in 2011 and 2012 continue this sampling as the tracer has made its way through Drake Passage, into the Scotia Sea, and over the North Scotia Ridge, a track of more than 3000 km. The initial results show that diapycnal, i.e., vertical, mixing west of Drake Passage where the bottom is relatively smooth is no larger than in most other regions of the open ocean. In contrast, there are strong velocity shears and intense turbulence levels over the rough topography in Drake Passage and diapycnal diffusivity of the tracer more than 10 times larger in Drake Passage and to the east than west of Drake Passage. The DIMES field program continues with the U.S. team collecting new velocity and turbulence data in the Scotia Sea. It is anticipated that the tracer will continue passing through the Scotia Sea until at least early 2014. The U.K. partners have scheduled sampling of the tracer on cruises at the North Scotia Ridge and in the eastern and central Scotia Sea in early 2013 and early 2014. The current project will continue the time series of the tracer at Drake Passage on two more U.S. led cruises, in late 2012 and late 2013. Trajectories through the Scotia Sea estimated from the tracer observations, from neutrally buoyant floats, and from numerical models will be used to accurately estimate mixing rates of the tracer and to locate where the mixing is concentrated. During the 2013 cruise the velocity and turbulence fields along high-resolution transects along the ACC and across the ridges of Drake Passage will be measured to see how far downstream of the ridges the mixing is enhanced, and to test the hypothesis that mixing is enhanced by breaking lee waves generated by flow over the rough topography. Broader Impacts: DIMES (see web site at http://dimes.ucsd.edu) involves many graduate students and post-doctoral researchers. Two graduate students, who would become expert in ocean turbulence and the processes generating it, will continue be trained on this project. The work in DIMES is ultimately motivated by the need to understand the overturning circulation of the global ocean. This circulation governs the transport and storage of heat and carbon dioxide within the huge oceanic reservoir, and thus plays a major role in regulating the earth?s climate. Understanding the circulation and how it changes in reaction to external forces is necessary to the understanding of past climate change and of how climate might change in the future, and is therefore of great importance to human well-being. The data collected and analyzed by the DIMES project will be assembled and made publicly available at the end of the project. The DIMES project is a process experiment sponsored by the U.S. CLIVAR (Climate variability and predictability) program.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Ledwell, James", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Studies of Turbulence and Mixing in the Antarctic Circumpolar Current, a Continuation of DIMES", "uid": "p0000846", "west": null}, {"awards": "0838948 Hofmann, Eileen", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 14 Nov 2013 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThe Ross Sea is a highly productive area within the Southern Ocean, but it experiences substantial variability in both physical (temperature, ice concentrations, salinity, winds, and current velocities) and biogeochemical (chlorophyll, productivity, micronutrients, higher trophic level standing stocks, gases, etc.) conditions. Understanding the temporal and spatial oceanographic variations in physical forcing is essential to understanding the ecological functioning within the Ross Sea. There are a number of models of the physical oceanography of the Ross Sea that characterize the observed circulation. Unfortunately, data on the appropriate time scales (daily, monthly, seasonal, and interannual) to completely evaluate those models are lacking. The proposed research is a demonstration project to characterize the physical and biological oceanography of the southern Ross Sea using newly developed Glider technology to sample the region continuously through the growing season, to collect temperature, salinity, fluorescence, oxygen and optical transmission data. These field data will be used to assist in evaluation of an eddy-resolving ROMS-based coupled circulation-biological model, and, along with satellite ocean color information, will be assimilated into an ecosystem model. Data assimilation techniques will reduce the model uncertainties of the circulation and food webs of the region. The intellectual merit of this effort arises from the combination of field-based investigations using a novel technology (one that is far more cost-effective than ship-based studies) with state-of-the-art biological-physical models and advanced data assimilation techniques. The research will provide new insights into the complex oceanographic phenomena of the Antarctic continental shelves and is a novel method of continuing the studies of the southern Ross Sea. Broader impacts of the proposed research include training of graduate and undergraduate students and partnership with several ongoing outreach programs dealing with scientific research in the Southern Ocean. At least 2 graduate students will be supported by this research, and it will be a critical component of a variety of outreach programs in Virginia, including a High School Marine Science Day, Boy and Girl Scout education, and middle school curriculum improvement. The investigators also will create a web site to foster immediate release of the data collected by the glider, and seek a linkage with schools at various levels (middle, high school and Universities) that potentially could incorporate the data into classroom activities", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hofmann, Eileen; Dinniman, Michael; Klinck, John M.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Seasonal Evolution of Chemical and Biological Variability in the Ross Sea", "uid": "p0000262", "west": null}, {"awards": "0838810 Hulbe, Christina", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 01 Jul 2013 00:00:00 GMT", "description": "Hulbe/0838810 \u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThis award supports a modeling study of the processes in West Antarctic grounding zones, the transition from ice resting on bedrock to ice floating on the ocean surface with an eye toward understanding the interrelated causes of rapid change in grounding line configuration and outlet flow. A combination of satellite remote sensing and numerical modeling will be used to investigate both past and ongoing patterns of change. New high-resolution surface elevation maps made from a novel combination of satellite laser altimetry and remotely observed surface shape provide a unique view of grounding zones. These data will be used to diagnose events associated with the shutdown of Kamb Ice Stream, to investigate a recent discharge event on Institute Ice Stream and to investigate ongoing change at the outlet of Whillans Ice Stream, along with other modern processes around the West Antarctic. An existing numerical model of coupled ice sheet, ice stream, and ice shelf flow will be used and improved as part of the research project. The broader impacts of the project relate to the importance of understanding the role of polar ice sheets in global sea level rise. The work will contribute to the next round of deliberations for the Intergovernmental Panel on Climate Change (IPCC). Improved views, interpretations, and insights into the physical processes that govern variability in ice sheet outlet streams will help correct the shortcomings of the last IPCC report that didn?t include the role of ice sheets in sea level rise. The PIs have a strong record of public outreach, involvement in the professional community, and student training.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "LABORATORY; Kamb Ice Stream; Grounding Line; FIELD INVESTIGATION; SATELLITES; Transition Zone; Ice Shelf Flow; Outlet Flow; Ice Sheet; Modeling; COMPUTERS; Antarctica", "locations": "Antarctica; Kamb Ice Stream", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hulbe, Christina; Fahnestock, Mark", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Mass Transit: Controls on Grounding and Ungrounding at Marine Ice Sheet Outlets", "uid": "p0000371", "west": null}, {"awards": "0823101 Ducklow, Hugh", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG1301", "datasets": [{"dataset_uid": "002731", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1301", "url": "https://www.rvdata.us/search/cruise/LMG1301"}, {"dataset_uid": "001425", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1301"}], "date_created": "Mon, 24 Jun 2013 00:00:00 GMT", "description": "Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. \u003cbr/\u003e\u003cbr/\u003eSince its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public\u0027s fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth\u0027s last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e PROFILERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Ducklow, Hugh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": null, "title": "Palmer, Antarctica Long Term Ecological Research Project", "uid": "p0000874", "west": null}, {"awards": "0839053 Ackley, Stephen", "bounds_geometry": "POLYGON((-180 -67.05,-170.9866 -67.05,-161.9732 -67.05,-152.9598 -67.05,-143.9464 -67.05,-134.933 -67.05,-125.9196 -67.05,-116.9062 -67.05,-107.8928 -67.05,-98.8794 -67.05,-89.866 -67.05,-89.866 -68.1033,-89.866 -69.1566,-89.866 -70.2099,-89.866 -71.2632,-89.866 -72.3165,-89.866 -73.3698,-89.866 -74.4231,-89.866 -75.4764,-89.866 -76.5297,-89.866 -77.583,-98.8794 -77.583,-107.8928 -77.583,-116.9062 -77.583,-125.9196 -77.583,-134.933 -77.583,-143.9464 -77.583,-152.9598 -77.583,-161.9732 -77.583,-170.9866 -77.583,180 -77.583,178.57 -77.583,177.14 -77.583,175.71 -77.583,174.28 -77.583,172.85 -77.583,171.42 -77.583,169.99 -77.583,168.56 -77.583,167.13 -77.583,165.7 -77.583,165.7 -76.5297,165.7 -75.4764,165.7 -74.4231,165.7 -73.3698,165.7 -72.3165,165.7 -71.2632,165.7 -70.2099,165.7 -69.1566,165.7 -68.1033,165.7 -67.05,167.13 -67.05,168.56 -67.05,169.99 -67.05,171.42 -67.05,172.85 -67.05,174.28 -67.05,175.71 -67.05,177.14 -67.05,178.57 -67.05,-180 -67.05))", "dataset_titles": "The Sea Ice System in Antarctic Summer, Oden Southern Ocean Expedition (OSO 2010-11)", "datasets": [{"dataset_uid": "600106", "doi": "10.15784/600106", "keywords": "Ice Core Records; Oceans; Oden; OSO1011; Sea Ice; Sea Ice Salinity; Sea Ice Thickness; Southern Ocean", "people": "Ackley, Stephen", "repository": "USAP-DC", "science_program": null, "title": "The Sea Ice System in Antarctic Summer, Oden Southern Ocean Expedition (OSO 2010-11)", "url": "https://www.usap-dc.org/view/dataset/600106"}], "date_created": "Fri, 03 May 2013 00:00:00 GMT", "description": "Several aspect of the seasonal melting and reformation cycle of Antarctic sea ice appear to be divergent from those occurring in the Arctic. This is most clearly demonstrated by the dramatic diminishing extent and thinning of the Arctic sea ice, to be contrasted to the changes in Antarctic sea-ice extent, which recently (decadaly) shows small increases. Current climate models do not resolve this discrepancy which likely results from both a lack of relevant observational sea-ice data in the Antarctic, along with inadequacies in the physical parameterization of sea-ice properties in climate models.\u003cbr/\u003e\u003cbr/\u003eResearchers will take advantage of the cruise track of the I/B Oden during transit through the Antarctic sea-ice zones in the region of the Bellingshausen, Amundsen and Ross (BAR) seas on a cruise to McMurdo Station. Because of its remoteness and inaccessibility, the BAR region is of considerable scientific interest as being one of the last under described and perhaps unexploited marine ecosystems left on the planet .\u003cbr/\u003e\u003cbr/\u003eA series of on station and underway observations of sea ice properties will be undertaken, thematically linked to broader questions of summer ice survival and baseline physical properties (e.g. estimates of heat and salt fluxes). In situ spatiotemporal variability of sea-ice cover extent, thickness and snow cover depths will be observed.", "east": 165.7, "geometry": "POINT(-142.083 -72.3165)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -67.05, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Ackley, Stephen", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.583, "title": "The Sea Ice System in Antarctic Summer, Oden Southern Ocean Expedition (OSO 2010-11)", "uid": "p0000676", "west": -89.866}, {"awards": "1039365 Rimmer, Susan", "bounds_geometry": null, "dataset_titles": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "datasets": [{"dataset_uid": "600121", "doi": "10.15784/600121", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Solid Earth; Transantarctic Mountains", "people": "Rimmer, Susan", "repository": "USAP-DC", "science_program": null, "title": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "url": "https://www.usap-dc.org/view/dataset/600121"}], "date_created": "Wed, 30 Jan 2013 00:00:00 GMT", "description": "This project studies the Permian-Triassic extinction event as recorded in sedimentary rocks from the Transantarctic Mountains of Antarctica. Two hundred and fifty million years ago most life on Earth was wiped out in a geologic instant. The cause is a subject of great debate. Researchers have identified a unique stratigraphic section near Shackleton glacier laid down during the extinction event. Organic matter from these deposits will be analyzed by density gradient centrifugation (DGC), which will offer detailed information on the carbon isotope composition. The age of these layers will be precisely dated by U/Pb-zircon-dating of intercalated volcanics. Combined, these results will offer detailed constraints on the timing and duration of carbon isotope excursions during the extinction, and offer insight into the coupling of marine and terrestrial carbon cycles. The broader impacts of this project include graduate and undergraduate student research, K12 outreach and teacher involvement, and societal relevance of the results, since the P/T extinction may have been caused by phenomena such as methane release, which could accompany global warming.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Rimmer, Susan", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Permian -Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuatios in Terrestrial Organic Matter", "uid": "p0000507", "west": null}, {"awards": "0739444 Rice, James", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 16 Jan 2013 00:00:00 GMT", "description": "Rice 0739444\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study the mode of formation and causes of glacial earthquakes. The paradigm for glacial flow has been that glaciers flow in a viscous manner, with major changes in the force balance occurring on the decade timescale or longer. The recent discovery of a number of even shorter timescale events has challenged this paradigm. In 2003, it was discovered that Whillans Ice Stream in West Antarctica displays stick-slip behavior on the 10-30 minute timescale, with ice stream speed increasing by a factor of 30 from already high speeds. In the past year, the minimum timescale has been pushed shorter by recognition that a class of recently discovered 50-second-long, magnitude-5 earthquakes are closely associated with changes in the force balance near the calving fronts of large outlet glaciers in both Greenland and East Antarctica. With no adequate theory existing to explain these relatively large earthquakes associated with outlet glaciers, we have begun to investigate the physical mechanisms that must be involved in allowing such a response in a system traditionally not thought capable of generating large variations in forces over timescales less than 100 seconds. The intellectual merit of the work is that large-amplitude, short-timescale variability of glaciers is an important mode of glacier dynamics that has not yet been understood from a first-principles physics perspective. The proposed research addresses this gap in understanding, tying together knowledge from numerous disciplines including glaciology, seismology and fault rupture dynamics, laboratory rock physics, granular flow, fracture mechanics, and hydrogeology. The broader impacts of the work are that there is societal as well as general scientific interest in the stability of the major ice sheets. However, without an understanding of the physical processes governing short time scale variability, it is unlikely that we will be able accurately predict the future of these ice sheets and their impact on sea level changes. The project will also contribute to the development and education of young scientists.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Rapid Glacial Motions; Not provided; Hydrogeology; Fracture Mechanics; Glacier Dynamics; Glacial Earthquakes; Granular Flow; Glacial Underflooding; Glaciology; Ice Stream Margins; Outlet Glaciers", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Rice, James; Platt, John; Suckale, Jenny; Perol, Thibaut; Tsai, Victor", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Transient and Rapid Glacial Motions, including Glacial Earthquakes", "uid": "p0000709", "west": null}, {"awards": "0632031 Das, Sarah; 0631973 Joughin, Ian", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 20 Jun 2012 00:00:00 GMT", "description": "Joughin 0631973\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to gather data to better understand the mass balance of the West Antarctic Ice Sheet, in the Pine Island and Thwaites region, through the combination of radar altimetry and surface-based ice-core measurements of accumulation. The intellectual merit of the project is that the results of the field work will provide information on decadal-scale average accumulation extending back through the last century and will help constrain a modeling effort to determine how coastal changes propagate inland, to allow better prediction of future change. Comparison of the basin averaged accumulation with ice discharge determined using Interferometric Synthetic Aperture Radar (InSAR) velocity data will provide improved mass-balance estimates. Study of changes in flow speed will produce a record of mass balance over the last three decades. Analysis of the satellite altimeter record in conjunction with annual accumulation estimates also will provide estimates of changes and variability in mass balance. The broader impacts of the work are that it will make a significant contribution to future IPCC estimates of sea level, which are important for projection of the impacts of increased sea level on coastal communities. The research will contribute to the graduate education of students at the Universities of Washington and Kansas and will enrich K-12 education through the direct participation of the PIs in classroom activities. Informal science education includes 4-day glacier flow demonstrations at the Polar Science Weekend held annually at the Pacific Science Center in Seattle. The project also will communicate results through Center for the Remote Sensing of Ice Sheets (CReSIS) outreach effort. All field and remotely-sensed data sets will be archived and distributed by the National Snow and Ice Data Center. This project is relevant to IPY in that the West Antarctic Ice Sheet is losing mass, in large part because of rapid thinning of the Amundsen Coast glaciers so, it will directly address the NSF IPY emphasis on \"ice sheet history and dynamics.\" The project is also international in scope.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "Not provided; FIELD INVESTIGATION; Flow Speed; Antarctic; LABORATORY; Ice Sheet Accumulation Rate; Mass Balance; Accumulation; Insar; SATELLITES; FIELD SURVEYS; Ice Core; Radar Altimetry; Ice Velocity", "locations": "Antarctic", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Joughin, Ian; Medley, Brooke; Das, Sarah", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repositories": null, "science_programs": null, "south": null, "title": "IPY: Collaborative Proposal: Constraining the Mass-Balance Deficit of the Amundsen Coast\u0027s Glaciers", "uid": "p0000542", "west": null}, {"awards": "0739766 Brook, Edward J.", "bounds_geometry": "POINT(-112.08 -79.47)", "dataset_titles": "WAIS Divide Ice Core CO2", "datasets": [{"dataset_uid": "609651", "doi": "10.7265/N5DV1GTZ", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Marcott, Shaun; Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice Core CO2", "url": "https://www.usap-dc.org/view/dataset/609651"}], "date_created": "Wed, 30 May 2012 00:00:00 GMT", "description": "Brook 0739766\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to create a 25,000-year high-resolution record of atmospheric CO2 from the WAIS Divide ice core. The site has high ice accumulation rate, relatively cold temperatures, and annual layering that should be preserved back to 40,000 years, all prerequisite for preserving a high quality, well-dated CO2 record. The new record will be used to examine relationships between Antarctic climate, Northern Hemisphere climate, and atmospheric CO2 on glacial-interglacial to centennial time scales, at unprecedented temporal resolution. The intellectual merit of the proposed work is simply that CO2 is the most important greenhouse gas that humans directly impact, and understanding the sources, sinks, and controls of atmospheric CO2 is a major goal for the global scientific community. Accurate chronology and detailed records are primary requirements for developing and testing models that explain and predict CO2 variability. The proposed work has several broader impacts. It contributes to the training of a post-doctoral researcher, who will transfer to a research faculty position during the award period and who will participate in graduate teaching and guest lecture in undergraduate courses. An undergraduate researcher will gain valuable lab training and conduct independent research. Bringing the results of\u003cbr/\u003ethe proposed work to the classroom will enrich courses taught by the PI. Outreach efforts will expose pre-college students to ice core research. The proposed work will enhance the laboratory facilities for ice core research at OSU, insuring that the capability for CO2 measurements exists for future projects. All data will be archived at the National Snow and Ice Data Center and other similar archives, per OPP policy. Highly significant results will be disseminated to the news media through OSU?s very effective News and Communications group. Carbon dioxide is the most important greenhouse gas that humans are directly changing. Understanding how CO2 and climate are linked on all time scales is necessary for predicting the future behavior of the carbon cycle and climate system, primarily to insure that the appropriate processes are represented in carbon cycle/climate models. Part of the proposed work emphasizes the relationship of CO2 and abrupt climate change. Understanding how future abrupt change might impact the carbon cycle is an important issue for society.", "east": -112.08, "geometry": "POINT(-112.08 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Carbon Dioxide; FIELD INVESTIGATION; CO2; Wais Divide-project; Ice Core; Antarctica; Climate; Gas Chromatography; Antarctic Ice Core; LABORATORY", "locations": "Antarctica", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Marcott, Shaun; Ahn, Jinho; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.47, "title": "Atmospheric Carbon Dioxide and Climate Change: The WAIS Divide Ice Core Record", "uid": "p0000044", "west": -112.08}, {"awards": "0125172 Gordon, Arnold", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0302; Expedition data of NBP0304C; Expedition data of NBP0304D; Expedition data of NBP0402; Expedition data of NBP0408; Expedition data of NBP0501", "datasets": [{"dataset_uid": "001692", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "002588", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0302", "url": "https://www.rvdata.us/search/cruise/NBP0302"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002629", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002620", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0408", "url": "https://www.rvdata.us/search/cruise/NBP0408"}, {"dataset_uid": "002624", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0304C", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}, {"dataset_uid": "002638", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0402", "url": "https://www.rvdata.us/search/cruise/NBP0402"}, {"dataset_uid": "002625", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0304D", "url": "https://www.rvdata.us/search/cruise/NBP0304D"}, {"dataset_uid": "001691", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304C"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "This study will investigate how the Antarctic Slope Front and continental slope morphology determine the exchanges of mass, heat, and fresh water between the shelf and the deep ocean, in particular those leading to outflows of dense water into intermediate and deep layers of the adjacent basins and into the world ocean circulation \u003cbr/\u003eWhile the importance to the global ocean circulation and climate of cold water masses originating in the Antarctic is unquestioned, the processes by which these water masses enter the deep ocean circulation are not. The primary goal of this work therefore is to identify the principal physical processes that govern the transfer of shelf-modified dense water into intermediate and deep layers of the adjacent deep ocean. At the same time, it seeks to understand the compensatory poleward flow of waters from the oceanic regime. The upper continental slope has been identified as the critical gateway for the exchange of shelf and deep ocean waters. Here the topography, velocity and density fields associated with the nearly ubiquitous front must strongly influence the advective and turbulent transfer of water properties between the shelf and oceanic regimes. The study has four specific objectives: [1] Determine the mean frontal structure and the principal scales of variability, and estimate the role of the front on cross-slope exchanges and mixing of adjacent water masses; [2] Determine the influence of slope topography and bathymetry on frontal location and outflow of dense Shelf Water; [3] Establish the role of frontal instabilities, benthic boundary layer transports, tides and other oscillatory processes on cross-slope advection and fluxes; and [4] Assess the effect of diapycnal mixing, lateral mixing identified through intrusions, and nonlinearities in the equation of state on the rate of descent and the fate of outflowing, near-freezing Shelf Water.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Gordon, Arnold; Cande, Steven; Visbeck, Martin; Jacobs, Stanley", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Anslope, Cross-slope Exchanges at the Antarctic Slope Front", "uid": "p0000807", "west": null}, {"awards": "0537609 Gee, Jeffrey", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "An Integrated Geomagnetic and Petrologic Study of the Dufek Complex", "datasets": [{"dataset_uid": "600053", "doi": "10.15784/600053", "keywords": "Antarctica; Dufek Complex; Geology/Geophysics - Other; Paleomagnetism; Solid Earth", "people": "Gee, Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "An Integrated Geomagnetic and Petrologic Study of the Dufek Complex", "url": "https://www.usap-dc.org/view/dataset/600053"}], "date_created": "Tue, 20 Dec 2011 00:00:00 GMT", "description": "This project studies remnant magnetization in igneous rocks from the Dufek igneous complex, Antarctica. Its primary goal is to understand variations in the Earth\u0027s magnetic field during the Mesozoic Dipole Low (MDL), a period when the Earth\u0027s magnetic field underwent dramatic weakening and rapid reversals. This work will resolve the MDL\u0027s timing and nature, and assess connections between reversal rate, geomagnetic intensity and directional variability, and large-scale geodynamic processes. The project also includes petrologic studies to determine cooling rate effects on magnetic signatures, and understand assembly of the Dufek as an igneous body. Poorly studied, the Dufek is amongst the world\u0027s largest intrusions and its formation is connected to the break-up of Gondwana. \u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this project include graduate and undergraduate education and international collaboration with a German and Chilean IPY project.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Gee, Jeffrey", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: An Integrated Geomagnetic and Petrologic Study of the Dufek Complex", "uid": "p0000510", "west": -180.0}, {"awards": "1048343 Warny, Sophie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Palynological samples list", "datasets": [{"dataset_uid": "601151", "doi": "10.15784/601151", "keywords": "Antarctica; Glaciology; Marine Geoscience; Marine Sediments; Microscope; Microscopy; Paleoclimate; Pollen", "people": "Warny, Sophie", "repository": "USAP-DC", "science_program": null, "title": "Palynological samples list", "url": "https://www.usap-dc.org/view/dataset/601151"}], "date_created": "Sat, 10 Dec 2011 00:00:00 GMT", "description": "Intellectual Merit: The PI proposes a high-resolution paleoenvironmental study of pollen, spore, fresh-water algae, and dinoflagellate cyst assemblages to investigate the palynological record of sudden warming events in the Antarctic as recorded by the ANDRILL SMS drill core and terrestrial sections. These data will be used to derive causal mechanisms for these rapid climate events. Terrestrial samples will be obtained at various altitudes in the Dry Valleys region. The pollen and spores will provide data on atmospheric conditions, while the algae will provide data on sea-surface conditions. These data will help identify the triggers for sudden climatic shifts. If they are caused by changes in oceanic currents, a signal will be visible in the dinocyst assemblages first as currents influence their distribution. Conversely, if these shifts are triggered by atmospheric factors, then the shifts will first affect plants and be visible in the pollen record. Broader impacts: The PI proposes a suite of activities to bring field-based climate change research to a broader audience. The PI will advise a diverse group of students and educators. The palynological data collected as part of this research will be utilized, in part, to develop new lectures on Antarctic palynology and these new lectures will be made available via a collaboration with the LSU HHMI program. In addition, the PI will direct three Louisiana middle-school teachers as they pursue a Masters of Natural Science for science educators. These teachers will help the PI develop a professional development program for science teachers. Community-based activities will be organized to raise science awareness and alert students and the public of opportunities in science.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "MICROFOSSILS; NOT APPLICABLE", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Warny, Sophie", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WISSARD; ANDRILL; SHALDRIL", "south": -75.0, "title": "CAREER: Deciphering Antarctic Climate Variability during the Temperate/Polar Transition and Improving Climate Change Literacy in Louisiana through a Companion Outreach Program", "uid": "p0000311", "west": -180.0}, {"awards": "0636898 Winckler, Gisela", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Nov 2011 00:00:00 GMT", "description": "Winckler/0636898\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to study dust sources in Antarctic ice cores. Atmospheric aerosols play an important role both in global biogeochemical cycles as well as in the climate system of the Earth. Records extracted from Antarctic ice cores inform us that dust deposition from the atmosphere to the ice sheet was 15-20 times greater during glacial periods than during interglacials, which raises the possibility that dust may be a key player in climate change on glacial-interglacial timescales. By characterizing potential source areas from South America, South Africa, and Australia as well as fresh glacial flour from Patagonia, the project will determine if the interglacial dust was mobilized from a distinct geographical region (e.g., Australia) or from a more heavily weathered source region in South America. The intellectual merit of the project is that it will contribute to reconstructing climate-related changes in the rate of dust deposition, and in the provenance of the dust, it will provide critical constraints on hydrology and vegetation in the source regions, as well as on the nature of the atmospheric circulation transporting dust to the archive location. In a recent pilot study it was found that there is a dramatic glacial to Holocene change in the 4He/Ca ratio in the dust extracted from ice from Dronning Maud Land, Antarctica, indicating a shift in the source of dust transported to Antarctica. The broader impacts of the project are that Helium isotopes and calcium measurements provide a wealth of information that can then be turned into critical input for dust-climate models. Improved models, which are able to accurately reconstruct paleo dust distribution, will help us to predict changes in dust in response to future climate variability. This information will contribute to an improvement of our integrated understanding of the Earth\u0027s climate system and, in turn, will better inform policy makers of those processes and conditions most susceptible to perturbation by climate change, thereby leading to more meaningful climate-change policy. The project will support a graduate student in the dual masters Earth and Environmental Science Journalism program. The lead-PI manages the rock noble gas laboratory at Lamont. Her leadership role in this facility impacts the training of undergraduate and graduate students as well as visiting scientists.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "Deposition; LABORATORY; Dust; Climate; Not provided; Climate Change; Helium Isotopes; FIELD INVESTIGATION; Biogeochemical Cycles", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Winckler, Gisela", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Tracing Glacial-interglacial Changes in the Dust Source to Antarctica using Helium Isotopes", "uid": "p0000265", "west": null}, {"awards": "0839084 Ortland, David", "bounds_geometry": "POLYGON((-63 -59,-62 -59,-61 -59,-60 -59,-59 -59,-58 -59,-57 -59,-56 -59,-55 -59,-54 -59,-53 -59,-53 -59.6,-53 -60.2,-53 -60.8,-53 -61.4,-53 -62,-53 -62.6,-53 -63.2,-53 -63.8,-53 -64.4,-53 -65,-54 -65,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-63 -64.4,-63 -63.8,-63 -63.2,-63 -62.6,-63 -62,-63 -61.4,-63 -60.8,-63 -60.2,-63 -59.6,-63 -59))", "dataset_titles": "Large- and Small-scale Dynamics and Meteor Studies in the MLT with a New-generation Meteor Radar on King George Island", "datasets": [{"dataset_uid": "600107", "doi": "10.15784/600107", "keywords": "Antarctica; Atmosphere; Meteorology; Meteor Radar", "people": "Fritts, David; Janches, Diego", "repository": "USAP-DC", "science_program": null, "title": "Large- and Small-scale Dynamics and Meteor Studies in the MLT with a New-generation Meteor Radar on King George Island", "url": "https://www.usap-dc.org/view/dataset/600107"}], "date_created": "Mon, 15 Aug 2011 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The project will employ a sophisticated meteor radar at the Brazilian Antarctic station Comandante Ferraz on King George Island for a number of synergetic research efforts of high interest to the international aeronomical community. The location of the radar will be at the tip of the Antarctic Peninsula - at a critical southern latitude of 62 degrees - to fill a current measurement gap from 54 to 68 degrees south. The radar will play a key role in Antarctic and inter-hemispheric studies of neutral atmosphere dynamics, defining global mesosphere and lower thermosphere structure and variability (from 80 to 105 km) and guiding advances of models accounting for the dynamics of this high-altitude region, including general circulation models, and climate and numerical weather prediction models. The unique radar measurement sensitivity will enable studies of: (1) the large-scale circulation and planetary waves, (2) the tidal structure and variability, (3) the momentum transport by small-scale gravity waves, (4) important, but unquantified, gravity wave - tidal interactions, (5) polar mesosphere summer echoes, and (6) meteor fluxes, head echoes, and non-specular trails, a number of which exhibit high latitudinal gradients at these latitudes. This radar will support extensive collaborations with U.S. and other scientists making measurements at other Antarctic and Arctic conjugate sites, including Brazilian scientists at C. Ferraz and U.S. and international colleagues having other instrumentation in the Antarctic, Arctic, and within South America. Links to the University of Colorado in the U.S., Instituto Nacional de Pesquisas Espaciais (INPE) in Brazil and Universidad Nacional de La Plata in Argentina will provide unique research opportunities for graduate and undergraduate students in the U.S. and South America.", "east": -53.0, "geometry": "POINT(-58 -62)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -59.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Fritts, David; Janches, Diego", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Large- and Small-scale Dynamics and Meteor Studies in the MLT with a New-generation Meteor Radar on King George Island", "uid": "p0000670", "west": -63.0}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": "POLYGON((26.27227 -42.81742,38.414467 -42.81742,50.556664 -42.81742,62.698861 -42.81742,74.841058 -42.81742,86.983255 -42.81742,99.125452 -42.81742,111.267649 -42.81742,123.409846 -42.81742,135.552043 -42.81742,147.69424 -42.81742,147.69424 -45.454494,147.69424 -48.091568,147.69424 -50.728642,147.69424 -53.365716,147.69424 -56.00279,147.69424 -58.639864,147.69424 -61.276938,147.69424 -63.914012,147.69424 -66.551086,147.69424 -69.18816,135.552043 -69.18816,123.409846 -69.18816,111.267649 -69.18816,99.125452 -69.18816,86.983255 -69.18816,74.841058 -69.18816,62.698861 -69.18816,50.556664 -69.18816,38.414467 -69.18816,26.27227 -69.18816,26.27227 -66.551086,26.27227 -63.914012,26.27227 -61.276938,26.27227 -58.639864,26.27227 -56.00279,26.27227 -53.365716,26.27227 -50.728642,26.27227 -48.091568,26.27227 -45.454494,26.27227 -42.81742))", "dataset_titles": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica; NB0101 Expedition Data; Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "datasets": [{"dataset_uid": "601177", "doi": "10.15784/601177", "keywords": "Antarctica; Biota; Diatom; East Antarctica; Microscopy; NBP0101; Oceans; Paleoceanography; Paleoclimate; R/v Nathaniel B. Palmer; Sediment Corer", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/601177"}, {"dataset_uid": "001879", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NB0101 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0101"}, {"dataset_uid": "601307", "doi": null, "keywords": "Antarctica; Biota; Diatom; East Antarctica; Mac. Robertson Shelf; Marine Geoscience; Microscope; NBP0101; Paleoclimate; Piston Corer; R/v Nathaniel B. Palmer; Sediment Core; Species Abundance", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": null, "title": "Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "url": "https://www.usap-dc.org/view/dataset/601307"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "9909367 Leventer This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a multi-institutional, international (US - Australia) marine geologic and geophysical investigation of Prydz Bay and the MacRobertson Shelf, to be completed during an approximately 60-day cruise aboard the RVIB N.B. Palmer. The primary objective is to develop a record of climate and oceanographic change during the Quaternary, using sediment cores collected via kasten and jumbo piston coring. Core sites will be selected based on seismic profiling (Seabeam 2112 and Bathy2000). Recognition of the central role of the Antarctic Ice Sheet to global oceanic and atmospheric systems is based primarily on data collected along the West Antarctic margin, while similar extensive and high resolution data sets from the much more extensive East Antarctic margin are sparse. Goals of this project include (1) development of a century- to millennial-scale record of Holocene paleoenvironments, and (2) testing of hypotheses concerning the sedimentary record of previous glacial and interglacial events on the shelf, and evaluation of the timing and extent of maximum glaciation along this 500 km stretch of the East Antarctic margin. High-resolution seismic mapping and coring of sediments deposited in inner shelf depressions will be used to reconstruct Holocene paleoenvironments. In similar depositional settings in the Antarctic Peninsula and Ross Sea, sedimentary records demonstrate millennial- and century- scale variability in primary production and sea-ice extent during the Holocene, which have been linked to chronological periodicities in radiocarbon distribution, suggesting the possible role of solar variability in driving some changes in Holocene climate. Similar high-resolution Holocene records from the East Antarctic margin will be used to develop a circum-Antarctic suite of data regarding the response of southern glacial and oceanographic systems to late Quaternary climate change. In addition, these data will help us to evaluate the response of the East Antarctic margin to global warming. Initial surveys of the Prydz Channel - Amery Depression region reveal sequences deposited during previous Pleistocene interglacials. The upper Holocene and lower (undated) siliceous units can be traced over 15,000 km2 of the Prydz Channel, but more sub-bottom seismic reflection profiling in conjunction with dense coring over this region is needed to define the spatial distribution and extent of the units. Chronological work will determine the timing and duration of previous periods of glacial marine sedimentation on the East Antarctic margin during the late Pleistocene. Analyses will focus on detailed sedimentologic, geochemical, micropaleontological, and paleomagnetic techniques. This multi-parameter approach is the most effective way to extract a valuable paleoenvironmental signal in these glacial marine sediments. These results are expected to lead to a significant advance in understanding of the behavior of the Antarctic ice-sheet and ocean system in the recent geologic past. The combination of investigators, all with many years of experience working in high latitude marine settings, will provide an effective team to complete the project. University and College faculty (Principal Investigators on this project) will supervise a combination of undergraduate and post-graduate students involved in all stages of the project so that educational objectives will be met in tandem with the research goals of the project.", "east": 147.69424, "geometry": "POINT(86.983255 -56.00279)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "R/V NBP; USAP-DC", "locations": null, "north": -42.81742, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Leventer, Amy", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -69.18816, "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "uid": "p0000609", "west": 26.27227}, {"awards": "0839069 Yager, Patricia", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1005", "datasets": [{"dataset_uid": "002654", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1005", "url": "https://www.rvdata.us/search/cruise/NBP1005"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThe Amundsen Sea Polynya is areally the most productive Antarctic polynya, exhibits higher chlorophyll levels during peak bloom and greater interannual variability than the better-studied Ross Sea Polynya ecosystem. Polynyas may be the key to understanding the future of polar regions as their extent is expected to increase with anthropogenic warming. The project will examine 1) sources of iron to the Amundsen Sea Polynya as a function of climate forcing, 2) phytoplankton community structure in relation to iron supply and mixed-layer depths, 3) the efficiency of the biological pump of carbon to depth and 4) the net flux of carbon as a function of climate and micronutrient forcing. The research also will compare results for the Amundsen Sea to existing data synthesis and modeling efforts for the Palmer LTER and Ross Sea. The project will 1) build close scientific collaborations between US and Swedish researchers; 2) investigate climate change implications with broad societal relevance; 3) train new researchers; 4) encourage participation in research science by underrepresented groups, and 5) involve broad dissemination of results via scientific literature and public outreach, including close interactions with NSF-supported PolarTrec and COSEE K-12 teachers.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Yager, Patricia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative research aboard Icebreaker Oden: ASPIRE (Amundsen Sea Polynya International Research Expedition)", "uid": "p0000844", "west": null}, {"awards": "0537532 Liston, Glen; 0538422 Hamilton, Gordon; 0538103 Scambos, Ted; 0538416 McConnell, Joseph; 0963924 Steig, Eric; 0538495 Albert, Mary", "bounds_geometry": "POLYGON((-180 -72.01667,-161.74667 -72.01667,-143.49334 -72.01667,-125.24001 -72.01667,-106.98668 -72.01667,-88.73335 -72.01667,-70.48002 -72.01667,-52.22669 -72.01667,-33.97336 -72.01667,-15.72003 -72.01667,2.5333 -72.01667,2.5333 -73.815003,2.5333 -75.613336,2.5333 -77.411669,2.5333 -79.210002,2.5333 -81.008335,2.5333 -82.806668,2.5333 -84.605001,2.5333 -86.403334,2.5333 -88.201667,2.5333 -90,-15.72003 -90,-33.97336 -90,-52.22669 -90,-70.48002 -90,-88.73335 -90,-106.98668 -90,-125.24001 -90,-143.49334 -90,-161.74667 -90,180 -90,162.25333 -90,144.50666 -90,126.75999 -90,109.01332 -90,91.26665 -90,73.51998 -90,55.77331 -90,38.02664 -90,20.27997 -90,2.5333 -90,2.5333 -88.201667,2.5333 -86.403334,2.5333 -84.605001,2.5333 -82.806668,2.5333 -81.008335,2.5333 -79.210002,2.5333 -77.411669,2.5333 -75.613336,2.5333 -73.815003,2.5333 -72.01667,20.27997 -72.01667,38.02664 -72.01667,55.77331 -72.01667,73.51998 -72.01667,91.26665 -72.01667,109.01332 -72.01667,126.75999 -72.01667,144.50666 -72.01667,162.25333 -72.01667,-180 -72.01667))", "dataset_titles": "Ice Core Chemistry from the Norwegian-U.S. Scientific Traverse of East Antarctica, IPY 2007-2009; Norwegian-U.S. Scientific Traverse of East Antarctica; This data set contains data from the publication Steig et al., Nature Geoscience, vol. 6, pages 372\u00e2\u20ac\u201c375 (doi:10.1038/ngeo1778), which includes isotope data from the Norway-US traverse in East Antarctica.", "datasets": [{"dataset_uid": "001305", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "This data set contains data from the publication Steig et al., Nature Geoscience, vol. 6, pages 372\u00e2\u20ac\u201c375 (doi:10.1038/ngeo1778), which includes isotope data from the Norway-US traverse in East Antarctica.", "url": "http://nsidc.org/data/nsidc-0536.html"}, {"dataset_uid": "609520", "doi": "10.7265/N5H41PC9", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; East Antarctica; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Chemistry from the Norwegian-U.S. Scientific Traverse of East Antarctica, IPY 2007-2009", "url": "https://www.usap-dc.org/view/dataset/609520"}, {"dataset_uid": "000112", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Norwegian-U.S. Scientific Traverse of East Antarctica", "url": "http://traverse.npolar.no/"}], "date_created": "Wed, 23 Feb 2011 00:00:00 GMT", "description": "This award supports a project of scientific investigations along two overland traverses in East Antarctica: one going from the Norwegian Troll Station (72deg. S, 2deg. E) to the United States South Pole Station (90deg. S, 0deg. E) in 2007-2008; and a return traverse starting at South Pole Station and ending at Troll Station by a different route in 2008-2009. The project will investigate climate change in East Antarctica, with the goals of understanding climate variability in Dronning Maud Land of East Antarctica on time scales of years to centuries and determining the surface and net mass balance of the ice sheet in this sector to understand its impact on sea level. The project will also investigate the impact of atmospheric and oceanic variability and human activities on the chemical composition of firn and ice in the region, and will revisit areas and sites first explored by traverses in the 1960\u0027s, for detection of possible changes and to establish benchmark datasets for future research efforts. In terms of broader impacts, the results of this study will add to understanding of climate variability in East Antarctica and its contribution to global sea level change. The project includes international exchange of graduate students between the institutions involved and international education of undergraduate students through classes taught by the PI\u0027s at UNIS in Svalbard. It involves extensive outreach to the general public both in Scandinavia and North America through the press, television, science museums, children\u0027s literature, and web sites. Active knowledge sharing and collaboration between pioneers in Antarctic glaciology from Norway and the US, with the international group of scientists and students involved in this project, provide a unique opportunity to explore the changes that half a century have made in climate proxies from East Antarctica, scientific tools, and the culture and people of science. The project is relevant to the International Polar Year (IPY) since it is a genuine collaboration between nations: the scientists involved have complementary expertise, and the logistics involved relies on assets unique to each nation. It is truly an endeavor that neither nation could accomplish alone. This project is a part of the Trans- Antarctic Scientific Traverse Expeditions Ice Divide of East Antarctica (TASTE-IDEA) which is also part of IPY.", "east": 2.5333, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PHOTOMETERS \u003e SPECTROPHOTOMETERS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; East Antarctic Plateau; FIXED OBSERVATION STATIONS; Glaciology; LABORATORY; FIELD SURVEYS; Permeability; Ice Core; Climate Variability; Firn; Accumulation Rate; Mass Balance; Snow; Gravity; Ice Sheet; GROUND-BASED OBSERVATIONS; Traverse; Not provided; Antarctic; Ice Core Chemistry; Antarctica; Density", "locations": "Antarctica; Antarctic; East Antarctic Plateau", "north": -72.01667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Courville, Zoe; Bell, Eric; Liston, Glen; Scambos, Ted; Hamilton, Gordon S.; McConnell, Joseph; Albert, Mary R.; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "NSIDC", "repositories": "NSIDC; Project website; USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Norwegian-United States IPY Scientific Traverse: Climate Variability and Glaciology in East Antarctica", "uid": "p0000095", "west": 2.5333}, {"awards": "0636506 Mayewski, Paul", "bounds_geometry": "POLYGON((-137.7 -75.7,-137.4 -75.7,-137.1 -75.7,-136.8 -75.7,-136.5 -75.7,-136.2 -75.7,-135.9 -75.7,-135.6 -75.7,-135.3 -75.7,-135 -75.7,-134.7 -75.7,-134.7 -75.773,-134.7 -75.846,-134.7 -75.919,-134.7 -75.992,-134.7 -76.065,-134.7 -76.138,-134.7 -76.211,-134.7 -76.284,-134.7 -76.357,-134.7 -76.43,-135 -76.43,-135.3 -76.43,-135.6 -76.43,-135.9 -76.43,-136.2 -76.43,-136.5 -76.43,-136.8 -76.43,-137.1 -76.43,-137.4 -76.43,-137.7 -76.43,-137.7 -76.357,-137.7 -76.284,-137.7 -76.211,-137.7 -76.138,-137.7 -76.065,-137.7 -75.992,-137.7 -75.919,-137.7 -75.846,-137.7 -75.773,-137.7 -75.7))", "dataset_titles": "Ion Concentrations from SPRESSO Ice Core, Antarctica; Mt. Moulton Ice Trench Mass Spectrometry Data, Antarctica", "datasets": [{"dataset_uid": "609472", "doi": "10.7265/N5VH5KSV", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mt Moulton; Paleoclimate", "people": "Korotkikh, Elena; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "Mt. Moulton Ice Trench Mass Spectrometry Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609472"}, {"dataset_uid": "609471", "doi": "10.7265/N508638J", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; ITASE; Paleoclimate; South Pole; SPRESSO Ice Core", "people": "Korotkikh, Elena; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "Ion Concentrations from SPRESSO Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609471"}], "date_created": "Thu, 29 Jul 2010 00:00:00 GMT", "description": "This award supports a project to examine an existing ice core of opportunity from South Pole (SPRESO core) to develop a 2000+ year long climate record. SPRESO ice core will be an annually dated, sub-annually-resolved reconstruction of past climate (atmospheric circulation, temperature, precipitation rate, and atmospheric chemistry) utilizing continuous, co-registered measurements (n=45) of: major ions, trace elements, and stable isotope series, plus selected sections for microparticle size and composition. The intellectual merit of this project relates to the fact that few 2000+ year records of this quality exist in Antarctica despite increasing scientific interest in this critical time period as the framework within which to understand modern climate. The scientific impact of this ice core investigation are that it will provide an in-depth understanding of climate variability; a baseline for assessing modern climate variability in the context of human activity; and a contribution to the prediction of future climate variability. The broader impact of this work is that the proposed research addresses important questions concerning the role of Antarctica in past, present, and future global change. Results will be translated into publicly accessible information through public lectures, media appearances, and an extensive outreach activity housed in our Institute. Our ice core activities provide a major basis for curriculum in K-12 and University plus a basis for several field and laboratory based graduate theses and undergraduate student projects. The project will support one PhD student for 3 years and undergraduate salaries. The Climate Change Institute has a long history of gender and ethnically diverse student and staff involvement in research.", "east": -134.7, "geometry": "POINT(-136.2 -76.065)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core Interpretation; Ions; US ITASE; Explorations; LABORATORY; Ice Core Data; Ice Core; Ice Analysis; Ice; Not provided; Antarctic Ice Sheet; Laboratory Investigation; Field Investigations; Ice Core Chemistry; Horizontal Ice Core; Ice Chemistry; Ice Sheet", "locations": "Antarctic Ice Sheet", "north": -75.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Korotkikh, Elena; Kreutz, Karl; Kurbatov, Andrei V.; Mayewski, Paul A.", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.43, "title": "Collaborative Proposal: 2000+ Year Detailed, Calibrated Climate Reconstruction from a South Pole Ice Core Set in an Antarctic - Global Scale Context", "uid": "p0000209", "west": -137.7}, {"awards": "9530398 Anderson, Robert; 9896290 Smith, Walker; 9530382 Smith, Walker", "bounds_geometry": "POLYGON((-179.9999 -43.5646,-143.99993 -43.5646,-107.99996 -43.5646,-71.99999 -43.5646,-36.00002 -43.5646,-0.000050000000016 -43.5646,35.99992 -43.5646,71.99989 -43.5646,107.99986 -43.5646,143.99983 -43.5646,179.9998 -43.5646,179.9998 -47.013473,179.9998 -50.462346,179.9998 -53.911219,179.9998 -57.360092,179.9998 -60.808965,179.9998 -64.257838,179.9998 -67.706711,179.9998 -71.155584,179.9998 -74.604457,179.9998 -78.05333,143.99983 -78.05333,107.99986 -78.05333,71.99989 -78.05333,35.99992 -78.05333,-0.000049999999987 -78.05333,-36.00002 -78.05333,-71.99999 -78.05333,-107.99996 -78.05333,-143.99993 -78.05333,-179.9999 -78.05333,-179.9999 -74.604457,-179.9999 -71.155584,-179.9999 -67.706711,-179.9999 -64.257838,-179.9999 -60.808965,-179.9999 -57.360092,-179.9999 -53.911219,-179.9999 -50.462346,-179.9999 -47.013473,-179.9999 -43.5646))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001874", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9802"}, {"dataset_uid": "002164", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9604"}, {"dataset_uid": "002162", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9604A"}, {"dataset_uid": "002138", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9708"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "95-30398 Anderson This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. The overall objectives of JGOFS are to determine and understand processes controlling the time-varying fluxes of carbon and associated biogenic elements, and to predict the response of marine biogeochemical processes to climate change. The Southern Ocean is critical in the global carbon cycle, as judged by its size and the physical processes which occur in it (e.g., deep and intermediate water formation), but its present quantitative role is uncertain. JGOFS objectives for the Southern Ocean study are as follows: 1) to constrain the fluxes of carbon (organic and inorganic) and to place these fluxes in the context of the contemporary carbon cycle; 2) to identify the factors and processes which regulate the magnitude and variability of primary productivity and the fate of biogenic matter; 3) to determine the response of the Southern Ocean to natural climate perturbations; and 4) to predict the response of the Southern Ocean to climate change. In order to successfully address these objectives, a large field program has been designed to provide various investigators the opportunity to test specific hypotheses which relate to these broadly-defined objectives. We expect the field test to begin in September 1996, and last through March 1998 using two ships, the R.V. Palmer, and the R.V. Thompson. As most of the investigators will use hydrographic and nutrient data from these cruises, this proposal requests funds for the support of the analysis of nutrient concentrations during these thirteen crui ses. A team of oceanographic experts from a variety of institutions has been assembled to complete these analyses; furthermore, the data will be scrutinized for errors and provided in a timely fashion to all PI\u0027s in the project, as well as to the relevant oceanographic data storage facilities. The hydrography and coring groups have been put together using the successful model for the Arabian Sea JGOFS study, and in conjunction with the nutrient data (supported under a separate proposal), will form a large portion of the Southern Ocean JGOFS database which both field investigators and modelers will use to clarify the role of the Southern Ocean in the global carbon cycle.", "east": 179.9998, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.5646, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Anderson, Robert; Smith, Walker; Honjo, Susumu", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.05333, "title": "Management and Scientific Service in Support of the U.S. JGOFS Southern Ocean Process Study: Hydrography, Coring and Site Survey", "uid": "p0000629", "west": -179.9999}, {"awards": "9011927 Ross, Robin; 9632763 Smith, Raymond", "bounds_geometry": "POLYGON((-79.68459 -52.36474,-77.851019 -52.36474,-76.017448 -52.36474,-74.183877 -52.36474,-72.350306 -52.36474,-70.516735 -52.36474,-68.683164 -52.36474,-66.849593 -52.36474,-65.016022 -52.36474,-63.182451 -52.36474,-61.34888 -52.36474,-61.34888 -54.071087,-61.34888 -55.777434,-61.34888 -57.483781,-61.34888 -59.190128,-61.34888 -60.896475,-61.34888 -62.602822,-61.34888 -64.309169,-61.34888 -66.015516,-61.34888 -67.721863,-61.34888 -69.42821,-63.182451 -69.42821,-65.016022 -69.42821,-66.849593 -69.42821,-68.683164 -69.42821,-70.516735 -69.42821,-72.350306 -69.42821,-74.183877 -69.42821,-76.017448 -69.42821,-77.851019 -69.42821,-79.68459 -69.42821,-79.68459 -67.721863,-79.68459 -66.015516,-79.68459 -64.309169,-79.68459 -62.602822,-79.68459 -60.896475,-79.68459 -59.190128,-79.68459 -57.483781,-79.68459 -55.777434,-79.68459 -54.071087,-79.68459 -52.36474))", "dataset_titles": "Expedition Data; Expedition data of NBP0105", "datasets": [{"dataset_uid": "001488", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0901"}, {"dataset_uid": "001578", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0601"}, {"dataset_uid": "001613", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0501"}, {"dataset_uid": "001649", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0301"}, {"dataset_uid": "001665", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0401"}, {"dataset_uid": "001817", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0201"}, {"dataset_uid": "002605", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0105", "url": "https://www.rvdata.us/search/cruise/NBP0105"}, {"dataset_uid": "002045", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9906"}, {"dataset_uid": "001998", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0001"}, {"dataset_uid": "002292", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9302"}, {"dataset_uid": "001884", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0101"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The annual advance and retreat of pack ice may be the major physical determinant of spatial and temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a six to eight year cycle in the maximum extent of pack ice in the winter. During this decade, winters were colder in 1980 and 1981, and again in 1986 and 1987. Winter-over survival in Adelie penguins varied on the same cycle, higher in winters with heavy pack ice. This Long Term Ecological Research (LTER) project will define ecological processes linking the extent of annual pack ice with the biological dynamics of different trophic levels within antarctic marine communities. The general focus is on interannual variability in representative populations from the antarctic marine food web and on mechanistic linkages that control the observed variability in order to develop broader generalizations applicable to other large marine environments. To achieve these objectives, data from several spatial and temporal scales, including remote sensing, a field approach that includes an annual monitoring program, a series of process-oriented research cruises, and a modeling effort to provide linkages on multiple spatial and temporal scales between biological and environmental components of the ecosystem will be employed.", "east": -61.34888, "geometry": "POINT(-70.516735 -60.896475)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V LMG; R/V NBP", "locations": null, "north": -52.36474, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Raymond; Ross, Robin Macurda; Fraser, William; Martinson, Douglas; Ducklow, Hugh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": -69.42821, "title": "Long-Term Ecological Research on the Antarctic Marine Ecosystem: An Ice-Dominated Environment", "uid": "p0000236", "west": -79.68459}, {"awards": "9528807 Gordon, Arnold", "bounds_geometry": "POLYGON((-69.58631 -52.35405,-66.572039 -52.35405,-63.557768 -52.35405,-60.543497 -52.35405,-57.529226 -52.35405,-54.514955 -52.35405,-51.500684 -52.35405,-48.486413 -52.35405,-45.472142 -52.35405,-42.457871 -52.35405,-39.4436 -52.35405,-39.4436 -53.54563,-39.4436 -54.73721,-39.4436 -55.92879,-39.4436 -57.12037,-39.4436 -58.31195,-39.4436 -59.50353,-39.4436 -60.69511,-39.4436 -61.88669,-39.4436 -63.07827,-39.4436 -64.26985,-42.457871 -64.26985,-45.472142 -64.26985,-48.486413 -64.26985,-51.500684 -64.26985,-54.514955 -64.26985,-57.529226 -64.26985,-60.543497 -64.26985,-63.557768 -64.26985,-66.572039 -64.26985,-69.58631 -64.26985,-69.58631 -63.07827,-69.58631 -61.88669,-69.58631 -60.69511,-69.58631 -59.50353,-69.58631 -58.31195,-69.58631 -57.12037,-69.58631 -55.92879,-69.58631 -54.73721,-69.58631 -53.54563,-69.58631 -52.35405))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002142", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9705"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9528807 Gordon The proposed project is part of a multi-institutional integrated study of the outflow of newly formed bottom water from the Weddell Sea and its dispersion into the South Atlantic Ocean. It builds upon earlier successful studies of the inflow of intermediate water masses into the Eastern Weddell Sea, their modification within the Weddell Gyre, and their interaction with bottom water formation processes in the western Weddell Sea. The study is called Deep Ocean Ventilation Through Antarctic Intermediate Layers (DOVETAIL) and includes six components involving hydrographic measurements, natural tracer experiments, and modeling studies. The study will be centered east of the Drake Passage where water masses from the Weddell Sea and the Scotia Sea come together in the Weddell-Scotia Confluence, and will be carried out in cooperation with the national antarctic programs of Germany and Spain. This particular component concerns observations of the temperature and salinity structure, as well as the chemical nature of the water column in the confluence region. The study has four related objectives. The first is to assess the quantity and the physical and chemical characteristics of Weddell Sea source waters for the confluence. The second is to describe the dominant processes associated with spreading and sinking of dense antarctic waters within the Weddell-Scotia Confluence. The third is to estimate the ventilation rate of the world ocean, and the fourth is to estimate seasonal fluctuations in the regional ocean transport and hydrographic structure and to assess the likely influence of seasonal to interannual variability on rates of ventilation by Weddell Sea waters. Ventilation of the deep ocean -- the rising of sub-surface water masses to the surface to be recharged with atmospheric gases and to give up heat to the atmosphere -- is a uniquely antarctic phenomenon that has significant consequences for global change by affecting the g lobal reservoir of carbon dioxide, and by modulating the amount and extent of seasonal sea ice in the southern hemisphere. This component will make systematic observations of the temperature salinity structure of the water and undertake an extensive sampling program for other chemical studies. The purpose is to identify the individual water masses and to relate their temperature and salinity characteristics to the modification processes within the Weddell Sea. ***", "east": -39.4436, "geometry": "POINT(-54.514955 -58.31195)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35405, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.26985, "title": "Deep Ocean Ventilation Through Antarctic Intermediate Layers (DOVETAIL)", "uid": "p0000630", "west": -69.58631}, {"awards": "9816616 Trivelpiece, Wayne", "bounds_geometry": "POLYGON((-70.860664 -52.350334,-69.5007142 -52.350334,-68.1407644 -52.350334,-66.7808146 -52.350334,-65.4208648 -52.350334,-64.060915 -52.350334,-62.7009652 -52.350334,-61.3410154 -52.350334,-59.9810656 -52.350334,-58.6211158 -52.350334,-57.261166 -52.350334,-57.261166 -53.6353506,-57.261166 -54.9203672,-57.261166 -56.2053838,-57.261166 -57.4904004,-57.261166 -58.775417,-57.261166 -60.0604336,-57.261166 -61.3454502,-57.261166 -62.6304668,-57.261166 -63.9154834,-57.261166 -65.2005,-58.6211158 -65.2005,-59.9810656 -65.2005,-61.3410154 -65.2005,-62.7009652 -65.2005,-64.060915 -65.2005,-65.4208648 -65.2005,-66.7808146 -65.2005,-68.1407644 -65.2005,-69.5007142 -65.2005,-70.860664 -65.2005,-70.860664 -63.9154834,-70.860664 -62.6304668,-70.860664 -61.3454502,-70.860664 -60.0604336,-70.860664 -58.775417,-70.860664 -57.4904004,-70.860664 -56.2053838,-70.860664 -54.9203672,-70.860664 -53.6353506,-70.860664 -52.350334))", "dataset_titles": "Expedition data of LMG0009; Expedition data of LMG0108A", "datasets": [{"dataset_uid": "002692", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0108A", "url": "https://www.rvdata.us/search/cruise/LMG0108A"}, {"dataset_uid": "002689", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0009", "url": "https://www.rvdata.us/search/cruise/LMG0009"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9816616 Trivelpiece Long-term seabird research conducted at Admiralty Bay, which is located on King George Island in the Antarctic Peninsula region, has documented annual variability in the life history parameters of the breeding biology and ecology of the Adelie, gentoo and chinstrap penguins. Twenty-year records acquired on these species, including survival and recruitment, population size and breeding success, and diets and foraging ecology have enabled scientists to test key hypotheses regarding the linkage between these predator parameters and variability in the Antarctic marine ecosystem. This project will focus on understanding the linkages between the physical environment and the population biology of penguins, in particular, sea ice coverage and its impact on krill availability as a food source for penguins. Krill is a key food web species in the Antarctic oceans and accounts for nearly one hundred percent of the prey eaten by dominant predators such as baleen whales, seals and penguins. Analysis of long-term data sets has suggested that years of heavy winter sea ice favor krill recruitment, as larval krill find refuge and food in the sea ice habitat. It has also been observed that years of heavy sea ice favor Adelie penguin recruitment and not that of chinstrap penguins. Aspects of the work include analysis of diet samples, shipboard krill sampling, survival and recruitment studies of penguins, satellite tracking of penguins during the breeding season, and analysis of satellite sea ice images. Penguins are the key species used to monitor the impact of commercial fisheries activities in the region, so this study will provide useful information to the Convention for the Conservation of Antarctic Marine Living Resources, which is the part of the Antarctic Treaty System which focuses on fisheries management.", "east": -57.261166, "geometry": "POINT(-64.060915 -58.775417)", "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.350334, "nsf_funding_programs": null, "paleo_time": null, "persons": "Trivelpiece, Wayne; Smith, Craig", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.2005, "title": "Penguin-Krill-Ice Interactions: The Impact of Environmental Variability on Penguin Demography", "uid": "p0000616", "west": -70.860664}, {"awards": "9910093 Powell, Thomas", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0104", "datasets": [{"dataset_uid": "002657", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0104", "url": "https://www.rvdata.us/search/cruise/NBP0104"}, {"dataset_uid": "002584", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0104", "url": "https://www.rvdata.us/search/cruise/NBP0104"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is a contribution to a coordinated attempt to understand the interactions of biological and physical dynamics by developing relationships among the evolution of the antarctic winter ice and snow cover, biological habitat variability, and the seasonal progression of marine ecological processes. The work will be carried out in the context of the Southern Ocean Experiment of the Global Ocean Ecosystem Dynamics Study (Globec), a large, multi-investigator study of the winter survival strategy of krill under the antarctic sea ice in the vicinity of Marguerite Bay on the western side of the Antarctic Peninsula. The objective of this project is to make a quantitative assessment of the small scale temperature and salinity structure of the oceanic surface layer in order to study the effect of stratification and turbulence on the biochemical and biological processes under the winter sea ice. The water masses on the continental shelf off Marguerite Bay consist of inflowing Upper Circumpolar Deep Water, which is relatively warm, salty, oxygen-poor, and nutrient-rich. In winter atmospheric processes cool and freshen this water, and recharge it with oxygen to produce Antarctic Surface Water which is diffused seaward, and supports both a sea ice cover and a productive krill-based food web. The modification processes work through mixing associated with shear instabilities of the internal wave field, double diffusion of salt and heat, and mixing driven by surface stress and convection. These processes will be quantified with two microstructure profilers, capable of resolving the small but crucial vertical variations that drive these processes. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Powell, Thomas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: WinDSSOcK: Winter Distribution and Success of Southern Ocean Krill", "uid": "p0000804", "west": null}, {"awards": "0444134 Mitchell, B. Gregory", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0606", "datasets": [{"dataset_uid": "002646", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0606", "url": "https://www.rvdata.us/search/cruise/NBP0606"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Shackleton Fracture Zone (SFZ) in Drake Passage of the Southern Ocean defines a boundary between low and high phytoplankton waters. Low chlorophyll water flowing through the southern Drake Passage emerges as high chlorophyll water to the east, and recent evidence indicates that the Southern Antarctic Circumpolar Current Front (SACCF) is steered south of the SFZ onto the Antarctic Peninsula shelf where mixing between the water types occurs. The mixed water is then advected off-shelf with elevated iron and phytoplankton biomass. The SFZ is therefore an ideal natural laboratory to improve the understanding of plankton community responses to natural iron fertilization, and how these processes influence export of organic carbon to the ocean interior. The bathymetry of the region is hypothesized to influence mesoscale circulation and transport of iron, leading to the observed patterns in phytoplankton biomass. The position of the Antarctic Circumpolar Current (ACC) is further hypothesized to influence the magnitude of the flow of ACC water onto the peninsula shelf, mediating the amount of iron transported into the Scotia Sea. To address these hypotheses, a research cruise will be conducted near the SFZ and to the east in the southern Scotia Sea. A mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments will complement rapid surface surveys of chemical, plankton, and hydrographic properties. Distributions of manganese, aluminum and radium isotopes will be determined to trace iron sources and estimate mixing rates. Phytoplankton and bacterial physiological states (including responses to iron enrichment) and the structure of the plankton communities will be studied. The primary goal is to better understand how plankton productivity, community structure and export production in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and distributions of limiting nutrients. The proposed work represents an interdisciplinary approach to address the fundamental physical, chemical and biological processes that contribute to the abrupt transition in chl-a which occurs near the SFZ. Given recent indications that the Southern Ocean is warming, it is important to advance the understanding of conditions that regulate the present ecosystem structure in order to predict the effects of climate variability. This project will promote training and learning across a broad spectrum of groups. Funds are included to support postdocs, graduate students, and undergraduates. In addition, this project will contribute to the development of content for the Polar Science Station website, which has been a resource since 2001 for instructors and students in adult education, home schooling, tribal schools, corrections education, family literacy programs, and the general public.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mitchell, B.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Plankton Community Structure and Iron Distribution in the Southern Drake Passage and Scotia Sea", "uid": "p0000837", "west": null}, {"awards": "9615053 Domack, Eugene", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9802", "datasets": [{"dataset_uid": "002718", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9802", "url": "https://www.rvdata.us/search/cruise/LMG9802"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Domack: OPP 9615053 Manley: OPP 9615670 Banerjee: OPP 9615695 Dunbar: OPP 9615668 Ishman: OPP 9615669 Leventer: OPP 9714371 Abstract This award supports a multi-disciplinary, multi-institutional effort to elucidate the detailed climate history of the Antarctic Peninsula during the Holocene epoch (the last 10,000 years). The Holocene is an important, but often overlooked, portion of the Antarctic paleoclimatic record because natural variability in Holocene climate on time scales of decades to millennia can be evaluated as a model for our present \"interglacial\" world. This project builds on over ten years of prior investigation into the depositional processes, productivity patterns and climate regime of the Antarctic Peninsula. This previous work identified key locations that contain ultra-high resolution records of past climatic variation. These data indicate that solar cycles operating on multi-century and millennial time scales are important regulators of meltwater production and paleoproductivity. These marine records can be correlated with ice core records in Greenland and Antarctica. This project will focus on sediment dispersal patterns across the Palmer Deep region. The objective is to understand the present links between the modern climatic and oceanographic systems and sediment distribution. In particular, additional information is needed regarding the influence of sea ice on the distribution of both biogenic and terrigenous sediment distribution. Sediment samples will be collected with a variety of grab sampling and coring devices. Analytical work will include carbon-14 dating of surface sediments using accellerator mass spectrometry and standard sedimentologic, micropaleontologic and magnetic granulometric analyses. This multiparameter approach is the most effective way to extract the paleoclimatic signals contained in the marine sediment cores. Two additional objectives are the deployment of sediment traps in front of the Muller Ice Shelf in Lallemand Fjord and seismic reflection work in conjunction with site augmentation funded through the Joint Oceanographic Institute. The goal of sediment trap work is to address whether sand transport and deposition adjacent to the ice shelf calving line results from meltwater or aeolian processes. In addition, the relationship between sea ice conditions and primary productivity will be investigated. The collection of a short series of seismic lines across the Palmer Deep basins will fully resolve the question of depth to acoustic basement. The combination of investigators on this project, all with many years of experience working in high latitude settings, provides an effective team to complete the project in a timely fashion. A combination of undergraduate, graduate and post-graduate students will be involved in all stages of the project so that educational objectives will be met in-tandem with research goals of the project.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Holocene Paleoenvironmental Change Along the Antarctic Peninsula: A Test of the Solar/Bi-Polar Signal", "uid": "p0000869", "west": null}, {"awards": "0087401 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Expedition data of NBP0301B; Expedition data of NBP0305A; Expedition data of NBP0501; Expedition data of NBP0601A; Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006); Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "datasets": [{"dataset_uid": "002622", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "601333", "doi": null, "keywords": "Antarctica; Flourometer; Mooring; NBP0601A; Ross Sea; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Fluorometer Data acquired on Moorings deployed the Ross Sea and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601333"}, {"dataset_uid": "601339", "doi": null, "keywords": "Antarctica; Current Meter; Mooring; NBP0601A; Oceans; Physical Oceanography; Ross Sea; Southern Ocean", "people": "Smith, Walker; Asper, Vernon", "repository": "USAP-DC", "science_program": null, "title": "Current Meter Data from the Ross Sea acquired with a Mooring deployed in December 2005 and recovered during the Nathaniel B. Palmer expedition NBP0601A (2006)", "url": "https://www.usap-dc.org/view/dataset/601339"}, {"dataset_uid": "002623", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601A", "url": "https://www.rvdata.us/search/cruise/NBP0601A"}, {"dataset_uid": "601341", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Mooring; NBP0601A; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Seawater Measurements; Southern Ocean", "people": "Asper, Vernon; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601A", "url": "https://www.usap-dc.org/view/dataset/601341"}, {"dataset_uid": "002621", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0305A", "url": "https://www.rvdata.us/search/cruise/NBP0305A"}, {"dataset_uid": "002627", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0501", "url": "https://www.rvdata.us/search/cruise/NBP0501"}, {"dataset_uid": "002583", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0301B", "url": "https://www.rvdata.us/search/cruise/NBP0301B"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "Ross Sea; AMD; USAP-DC; Amd/Us; USA/NSF; R/V NBP", "locations": "Ross Sea", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Interannual Variability in the Antarctic-Ross Sea (IVARS): Nutrients and Seasonal Production", "uid": "p0000803", "west": null}, {"awards": "9118439 Karl, David", "bounds_geometry": "POLYGON((-76.8432 -52.3533,-74.99221 -52.3533,-73.14122 -52.3533,-71.29023 -52.3533,-69.43924 -52.3533,-67.58825 -52.3533,-65.73726 -52.3533,-63.88627 -52.3533,-62.03528 -52.3533,-60.18429 -52.3533,-58.3333 -52.3533,-58.3333 -54.01689,-58.3333 -55.68048,-58.3333 -57.34407,-58.3333 -59.00766,-58.3333 -60.67125,-58.3333 -62.33484,-58.3333 -63.99843,-58.3333 -65.66202,-58.3333 -67.32561,-58.3333 -68.9892,-60.18429 -68.9892,-62.03528 -68.9892,-63.88627 -68.9892,-65.73726 -68.9892,-67.58825 -68.9892,-69.43924 -68.9892,-71.29023 -68.9892,-73.14122 -68.9892,-74.99221 -68.9892,-76.8432 -68.9892,-76.8432 -67.32561,-76.8432 -65.66202,-76.8432 -63.99843,-76.8432 -62.33484,-76.8432 -60.67125,-76.8432 -59.00766,-76.8432 -57.34407,-76.8432 -55.68048,-76.8432 -54.01689,-76.8432 -52.3533))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002292", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9302"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The annual advance and retreat of pack ice may be the major physical determinant of spatial/temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a 6 to 8 year cycle in the maximum extent of pack ice in the winter. During this decade winters were colder in 1980 and 1981, and again in 1986 and 1987. In order to understand the interactions between pack ice and ecosystem dynamics, especially the influences of the well- documented interannual variability in ice cover on representative populations, a long-term ecological research (LTER) site has been established in the Antarctic Peninsula region near Palmer Station. The LTER project, will conduct comprehensive measurements of ice-dominated ecosystems in this region with a focus on primary production, krill populations and swarms and seabirds. A primary emphasis will be placed on the development of ecosystem models that will provide a predictive capability for issues related to global environmental change. This proposal will add to the existing LTER project detailed studies of the biogeochemical cycling of carbon and associated bioelements. The microbiology and carbon flux component of LTER will provide measurements of a suite of core parameters relevant to the carbon cycle and will test several hypotheses pertaining to carbon flux, including bacterial productivity and nutrient regeneration.", "east": -58.3333, "geometry": "POINT(-67.58825 -60.67125)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.3533, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Karl, David; Ross, Robin Macurda", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": "LTER", "south": -68.9892, "title": "Long-term Ecological Research (LTER) on the Antarctic Marine Ecosystem: Microbiology and Carbon Flux", "uid": "p0000651", "west": -76.8432}, {"awards": "9117721 Jeffries, Martin", "bounds_geometry": "POLYGON((-110.149 -52.353,-104.86076 -52.353,-99.57252 -52.353,-94.28428 -52.353,-88.99604 -52.353,-83.7078 -52.353,-78.41956 -52.353,-73.13132 -52.353,-67.84308 -52.353,-62.55484 -52.353,-57.2666 -52.353,-57.2666 -54.17539,-57.2666 -55.99778,-57.2666 -57.82017,-57.2666 -59.64256,-57.2666 -61.46495,-57.2666 -63.28734,-57.2666 -65.10973,-57.2666 -66.93212,-57.2666 -68.75451,-57.2666 -70.5769,-62.55484 -70.5769,-67.84308 -70.5769,-73.13132 -70.5769,-78.41956 -70.5769,-83.7078 -70.5769,-88.99604 -70.5769,-94.28428 -70.5769,-99.57252 -70.5769,-104.86076 -70.5769,-110.149 -70.5769,-110.149 -68.75451,-110.149 -66.93212,-110.149 -65.10973,-110.149 -63.28734,-110.149 -61.46495,-110.149 -59.64256,-110.149 -57.82017,-110.149 -55.99778,-110.149 -54.17539,-110.149 -52.353))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002253", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9405"}, {"dataset_uid": "002283", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9305"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is an examination of the physical and structural properties of the antarctic ice pack in the Amundsen, Bellingshausen, and Ross Seas, with the goal of defining the geographical variability of various ice types, the deformation processes that are active in the antarctic ice pack, and the large-scale thermodynamics and heat exchange processes of the ice- covered Southern Ocean. An additional goal is to relate specific characteristics of antarctic sea ice to its synthetic aperture radar (SAR) signature as observed from satellites. Physical properties include the salinity, temperature, and brine volumes, while structural properties include the fraction of frazil, platelet, and congelation ice of the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice (which has been observed to be generally in excess of 50% in Weddell Sea ice floes) is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The integration of sea ice field observations and synthetic aperture radar data analysis and modeling studies will contribute to a better understanding of sea ice parameters and their geophysical controls, and will be useful in defining the kind of air-ice-ocean interactions that can be studied using SAR data, as well as having broader relevance and application to atmospheric, biological, and oceanographic investigations of the Southern Ocean.", "east": -57.2666, "geometry": "POINT(-83.7078 -61.46495)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.353, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.5769, "title": "Sea Ice Physical-Structrual Characteristics: Development and SAR Signature in the Pacific Sector of the Southern Ocean", "uid": "p0000647", "west": -110.149}, {"awards": "0125985 Trivelpiece, Wayne", "bounds_geometry": "POLYGON((-70.907646 -52.351532,-69.6445116 -52.351532,-68.3813772 -52.351532,-67.1182428 -52.351532,-65.8551084 -52.351532,-64.591974 -52.351532,-63.3288396 -52.351532,-62.0657052 -52.351532,-60.8025708 -52.351532,-59.5394364 -52.351532,-58.276302 -52.351532,-58.276302 -53.6039408,-58.276302 -54.8563496,-58.276302 -56.1087584,-58.276302 -57.3611672,-58.276302 -58.613576,-58.276302 -59.8659848,-58.276302 -61.1183936,-58.276302 -62.3708024,-58.276302 -63.6232112,-58.276302 -64.87562,-59.5394364 -64.87562,-60.8025708 -64.87562,-62.0657052 -64.87562,-63.3288396 -64.87562,-64.591974 -64.87562,-65.8551084 -64.87562,-67.1182428 -64.87562,-68.3813772 -64.87562,-69.6445116 -64.87562,-70.907646 -64.87562,-70.907646 -63.6232112,-70.907646 -62.3708024,-70.907646 -61.1183936,-70.907646 -59.8659848,-70.907646 -58.613576,-70.907646 -57.3611672,-70.907646 -56.1087584,-70.907646 -54.8563496,-70.907646 -53.6039408,-70.907646 -52.351532))", "dataset_titles": "Expedition Data; Expedition data of LMG0208", "datasets": [{"dataset_uid": "001747", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0208"}, {"dataset_uid": "002724", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0208", "url": "https://www.rvdata.us/search/cruise/LMG0208"}, {"dataset_uid": "001752", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0207"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Seabird research conducted at Admiralty Bay, King George Island in the Antarctic Peninsula region has documented annual variability in the life history parameters of the population biology of three related penguin species: the Adelie, the gentoo and the chinstrap (Pygoscelis adeliae, P. papua and P. antarctica, respectively). This long-term study has collected twenty-five years of data on the three related species, including survival and recruitment, population size and breeding success, and diets and foraging ecology. The current project will extend the research linking penguin demography and foraging ecology to variability in the Antarctic marine ecosystem. A major focus of this work will be on the Adelie and gentoo penguin population biology data and the distribution and trophic interactions among the three Pygoscelis species during the breeding season and the non-breeding, winter period. Recent results have provided the first detailed data on the wintering distributions of Adelie and chinstrap penguins in the Antarctic Peninsula region, through the use of satellite tags and time-depth recorders to examine the post-fledging foraging. Specific topics of research include an examination of the size and sex composition of krill captured by penguins feeding chicks and krill collected concurrently by net hauls in the adjacent marine environment and the length-frequency distribution of krill collected from penguin diet samples. The over winter survival of penguin breeding adults and the recruitment of young (two to four year old) pre-breeding penguins to their natal colony will be compared to the extent of sea ice in the winter prior to the breeding season. These variables are expected to be positively correlated for the Adelie but negatively correlated to the chinstrap penguin. Detailed studies of the adult gentoo penguins, which do not disperse widely from the natal colony, will be conducted using satellite tags. The data collected in this study will improve an understanding of the structure and function of the Antarctic through research on the impact of environmental variation on the structure of upper trophic level predators such as the Pygoscelis penguins.", "east": -58.276302, "geometry": "POINT(-64.591974 -58.613576)", "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.351532, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Trivelpiece, Wayne; Stearns, Charles R.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.87562, "title": "Foraging Behavior and Demography of Pygoscelis Penguins", "uid": "p0000597", "west": -70.907646}, {"awards": "9910102 Padman, Laurence", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0104; Expedition data of NBP0202; Expedition data of NBP0204", "datasets": [{"dataset_uid": "002586", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0202", "url": "https://www.rvdata.us/search/cruise/NBP0202"}, {"dataset_uid": "002597", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0204", "url": "https://www.rvdata.us/search/cruise/NBP0204"}, {"dataset_uid": "002606", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0104", "url": "https://www.rvdata.us/search/cruise/NBP0104"}, {"dataset_uid": "002643", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0204", "url": "https://www.rvdata.us/search/cruise/NBP0204"}, {"dataset_uid": "002657", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0104", "url": "https://www.rvdata.us/search/cruise/NBP0104"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is a contribution to a coordinated attempt to understand the interactions of biological and physical dynamics by developing relationships among the evolution of the antarctic winter ice and snow cover, biological habitat variability, and the seasonal progression of marine ecological processes. The work will be carried out in the context of the Southern Ocean Experiment of the Global Ocean Ecosystem Dynamics Study (Globec), a large, multi-investigator study of the winter survival strategy of krill under the antarctic sea ice in the vicinity of Marguerite Bay on the western side of the Antarctic Peninsula. There are several aspects to this project: One is the collection, analysis, and archiving of Acoustic Doppler Current Profiler (ADCP), and Conductivity-Temperature-Depth (CTD) data in order to characterize mesoscale circulation features and the regional hydrography. Another is to develop an accurate and fully validated model of tidal currents in Marguerite Bay. A third is to provide a data set of small-scale processes such as shear instabilities, tidal stirring, mesoscale eddies, and double diffusion, that are required for the effective parameterization of the vertical diffusivities of heat, salt, and nutrients. The results of this project will provide a unified data set that satisfies the data requirement of the coordinated chemical and biological studies which will link water column and sea ice processes with the biology of krill and its predators. The results further will help to link these winter observations to similar observations made in summer and elsewhere around Antarctic in the international context of the Globec program. The overall objective is to develop a comprehensive ecosystem model that will test our understanding of the system, determine its sensitivities, and to provide an organizing mechanism for integrating the Southern Ocean Globec observations. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Padman, Laurence", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Mesoscale Circulation, Tides and Mixing on the Western Antarctic Peninsula Shelf: A Component of WINDSSOCK (ESR proposal #99-48)", "uid": "p0000806", "west": null}, {"awards": "0344275 Trivelpiece, Wayne", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG0412", "datasets": [{"dataset_uid": "002683", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0412", "url": "https://www.rvdata.us/search/cruise/LMG0412"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Seabird research conducted at Admiralty Bay, King George Island in the Antarctic Peninsula region has documented annual variability in the life history parameters of the population biology of three related penguin species: the Adelie, the gentoo and the chinstrap (Pygoscelis adeliae, P. papua and P. antarctica, respectively). This long-term study has collected twenty-five years of data on the three related species, including survival and recruitment, population size and breeding success, and diets and foraging ecology. The current project will extend the research linking penguin demography and foraging ecology to variability in the Antarctic marine ecosystem. A major focus of this work will be on the Adelie and gentoo penguin population biology data and the distribution and trophic interactions among the three Pygoscelis species during the breeding season and the non-breeding, winter period. Recent results have provided the first detailed data on the wintering distributions of Adelie and chinstrap penguins in the Antarctic Peninsula region, through the use of satellite tags and time-depth recorders to examine the post-fledging foraging. Specific topics of research include an examination of the size and sex composition of krill captured by penguins feeding chicks and krill collected concurrently by net hauls in the adjacent marine environment and the length-frequency distribution of krill collected from penguin diet samples. The over winter survival of penguin breeding adults and the recruitment of young (two to four year old) pre-breeding penguins to their natal colony will be compared to the extent of sea ice in the winter prior to the breeding season. These variables are expected to be positively correlated for the Adelie but negatively correlated to the chinstrap penguin. Detailed studies of the adult gentoo penguins, which do not disperse widely from the natal colony, will be conducted using satellite tags. The data collected in this study will improve an understanding of the structure and function of the Antarctic through research on the impact of environmental variation on the structure of upper trophic level predators such as the Pygoscelis penguins.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Trivelpiece, Wayne", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Foraging Behavior and Demography of Pygoscelis Penguins", "uid": "p0000860", "west": null}, {"awards": "0538148 Huber, Bruce", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0801; Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ; Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "datasets": [{"dataset_uid": "601343", "doi": null, "keywords": "Antarctica; Mooring; NBP1101; Ross Sea; Salinity; Southern Ocean; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ", "url": "https://www.usap-dc.org/view/dataset/601343"}, {"dataset_uid": "001517", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0801"}, {"dataset_uid": "002647", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0801", "url": "https://www.rvdata.us/search/cruise/NBP0801"}, {"dataset_uid": "601344", "doi": null, "keywords": "Antarctica; Cape Adare; Mooring; NBP0801; Physical Oceanography; Ross Sea; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": null, "title": "Processed CurrentMeter Data from the Ross Sea near Antarctica acquired during the Nathaniel B. Palmer expedition NBP0801", "url": "https://www.usap-dc.org/view/dataset/601344"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "An array of moorings will be deployed and maintained east of Cape Adare, Antarctica, at the northwestern corner of the Ross Sea to observe the properties of Antarctic Bottom Water (AABW) exiting the Ross Sea. This location has been identified from recent studies as an ideal place to make such measurements. Antarctic Bottom Water has the highest density of the major global water masses, and fills the deepest parts of the world\u0027s oceans. Because it obtains many of its characteristics during its contact with the atmosphere and with glacial ice along the continental margins of Antarctica, it is expected that changes in newly-formed AABW may represent an effective indicator for abrupt climate change. The heterogeneous nature of the source regions around Antarctica complicates the observation of newly-formed AABW properties. The two most important source regions for AABW are within the Weddell and the Ross Seas, with additional sources drawn from the east Antarctic margins. In the northwestern Weddell Sea, several programs have been undertaken in the last decade to monitor the long term variability of Weddell Sea Deep and Bottom Water, precursors of AABW originating from the Weddell Sea, however no such systematic efforts have yet been undertaken to make longterm measurements of outflow from the Ross Sea. The proposed study will significantly improve our knowledge of the long term variability in the outflow of deep and bottom water from the Ross Sea, and will provide the beginnings of a long-term monitoring effort which ultimately will allow detection of changes in the ocean in the context of global climate change. When joined with similar efforts ongoing in the Weddell Sea, long-term behavior and possible coupling of these two important sources of the ocean\u0027s deepest water mass can be examined in detail.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Caron, Bruce", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Cape Adare Long-term Mooring (CALM)", "uid": "p0000838", "west": null}, {"awards": "9315029 Smith, Kenneth", "bounds_geometry": "POLYGON((-70.90721 -52.35561,-68.309229 -52.35561,-65.711248 -52.35561,-63.113267 -52.35561,-60.515286 -52.35561,-57.917305 -52.35561,-55.319324 -52.35561,-52.721343 -52.35561,-50.123362 -52.35561,-47.525381 -52.35561,-44.9274 -52.35561,-44.9274 -53.476372,-44.9274 -54.597134,-44.9274 -55.717896,-44.9274 -56.838658,-44.9274 -57.95942,-44.9274 -59.080182,-44.9274 -60.200944,-44.9274 -61.321706,-44.9274 -62.442468,-44.9274 -63.56323,-47.525381 -63.56323,-50.123362 -63.56323,-52.721343 -63.56323,-55.319324 -63.56323,-57.917305 -63.56323,-60.515286 -63.56323,-63.113267 -63.56323,-65.711248 -63.56323,-68.309229 -63.56323,-70.90721 -63.56323,-70.90721 -62.442468,-70.90721 -61.321706,-70.90721 -60.200944,-70.90721 -59.080182,-70.90721 -57.95942,-70.90721 -56.838658,-70.90721 -55.717896,-70.90721 -54.597134,-70.90721 -53.476372,-70.90721 -52.35561))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002230", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9506"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9315029 Smith The annual expansion and retreat of pack ice in the Southern Ocean are the largest seasonal processes in the World Ocean. This seasonal migration of the ice cover has a profound impact on the pelagic community in the upper 100 m of the oceanic water column where the interactions between ice cover and apex predators, such as seabirds and mammals, are most intense. This unique pelagic community has been mainly studied with ship-based operations. However, there are well recognized problems associated with shipboard sampling of the epipelagic community under pack ice and the need to monitor this community on long-time scales sufficient to examine the extreme temporal variability of this environment. To examine continuous temporal variability, the project will develop a vertically-profiling pump sampler for the collections of zooplankton and micronekton over programmable depth intervals under pack ice in the Weddell Sea. Once developed and field tested, this instrument will be deployed concurrently with previously developed upward-looking, vertically-profiling acoustic arrays for a period of one year. The combined mooring project will monitor the vertical distribution, abundance and size frequency of acoustically detectable zooplankton and micronekton in the upper 100 m of the water column in an area that experiences ice cover during 7-8 months of the year. This project will also include seasonal shipboard sampling on three cruises over the course of the one year field study. A successful deployment of these long-term mooring arrays and retrieval of data from the field will contribute to a greater understanding of how epipelagic communities function under pack ice in the Southern Ocean. This is a jointly sponsored project of the Office of Polar Programs and the Division of Ocean Sciences. ***", "east": -44.9274, "geometry": "POINT(-57.917305 -57.95942)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35561, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Kenneth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -63.56323, "title": "Seasonal Ice Cover and its Impact on the Epipelagic Community in the Northwestern Weddell Sea: Long Time-Series Monitoring", "uid": "p0000644", "west": -70.90721}, {"awards": "0440687 Costa, Daniel", "bounds_geometry": "POLYGON((-68.2775 -52.7602,-67.59761 -52.7602,-66.91772 -52.7602,-66.23783 -52.7602,-65.55794 -52.7602,-64.87805 -52.7602,-64.19816 -52.7602,-63.51827 -52.7602,-62.83838 -52.7602,-62.15849 -52.7602,-61.4786 -52.7602,-61.4786 -54.24701,-61.4786 -55.73382,-61.4786 -57.22063,-61.4786 -58.70744,-61.4786 -60.19425,-61.4786 -61.68106,-61.4786 -63.16787,-61.4786 -64.65468,-61.4786 -66.14149,-61.4786 -67.6283,-62.15849 -67.6283,-62.83838 -67.6283,-63.51827 -67.6283,-64.19816 -67.6283,-64.87805 -67.6283,-65.55794 -67.6283,-66.23783 -67.6283,-66.91772 -67.6283,-67.59761 -67.6283,-68.2775 -67.6283,-68.2775 -66.14149,-68.2775 -64.65468,-68.2775 -63.16787,-68.2775 -61.68106,-68.2775 -60.19425,-68.2775 -58.70744,-68.2775 -57.22063,-68.2775 -55.73382,-68.2775 -54.24701,-68.2775 -52.7602))", "dataset_titles": "Expedition Data; Expedition data of LMG0706; Habitat Utilization of Southern Ocean Seals: Foraging Behavior of Crabeater and Elephant Seals Using Novel Methods of Oceanographic Data Collection", "datasets": [{"dataset_uid": "002713", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0706", "url": "https://www.rvdata.us/search/cruise/LMG0706"}, {"dataset_uid": "001534", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0705"}, {"dataset_uid": "600044", "doi": "10.15784/600044", "keywords": "Bellingshausen Sea; Biota; Oceans; Seals; Southern Ocean", "people": "Klinck, John M.; Costa, Daniel; Crocker, Daniel; Goebel, Michael; Hofmann, Eileen", "repository": "USAP-DC", "science_program": null, "title": "Habitat Utilization of Southern Ocean Seals: Foraging Behavior of Crabeater and Elephant Seals Using Novel Methods of Oceanographic Data Collection", "url": "https://www.usap-dc.org/view/dataset/600044"}, {"dataset_uid": "002714", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0706", "url": "https://www.rvdata.us/search/cruise/LMG0706"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "As long-lived animals, marine mammals must be capable of accommodating broad variations in food resources over large spatial and temporal scales. While this is true of all marine mammals, variation in the physical and biological environmental is particularly profound in the Southern Ocean. A basic understanding of the foraging behavior and habitat utilization of pelagic predators requires knowledge of this spatial and temporal variation, coupled with information of how they respond to these changes. Current understanding of these associations is primarily limited to population level studies where animal abundance has been correlated with oceanography. Although these studies are informative, they cannot provide insights into the strategies employed by individual animals nor can they provide insights into the spatial or temporal course of these interactions. \u003cbr/\u003e\u003cbr/\u003eRecent technological advances in instrumentation make it possible to extend an understanding beyond the simple linkage of prey and predator distributions with environmental features. The key to understanding the processes that lead to high predator abundance is the identification of the specific foraging behaviors associated with different features of the water column. This study will accomplish these objectives by combining accurate positional data, measures of diving and foraging behavior, animal-derived water-column temperature and salinity data, and available oceanographic data. This project will examine the foraging behavior and habitat utilization of two species of contrasting foraging ecology, the southern elephant seal, Mirounga leonina, and the crabeater seal, Lobodon carcinophagus in the Western Antarctic Peninsula, a region of strong environmental gradients. Although these two species are phylogenetically related, they utilize substantially different but adjacent habitat types. Southern elephant seals are predominantly pelagic, moving throughout the southern ocean, venturing occasionally into the seasonal pack ice whereas crabeater seals range throughout the seasonal pack ice, venturing occasionally into open water. The relationship of specific foraging behaviors and animal movement patterns to oceanographic and bathymetric features develop and test models of the importance of these features in defining habitat use will be determined along with a comparison of how individuals of each species respond to annual variability in the marine environment. The physical oceanography of the Southern Ocean is inherently complex as are the biological processes that are intrinsically linked to oceanographic processes. Significant resources are currently being directed toward developing mathematical models of physical oceanographic processes with the goals of better understanding the role that the Southern Ocean plays in global climate processes, predicting the responses of ocean and global scale processes to climate change, and understanding the linkages between physical and biological oceanographic processes. These efforts have been limited by the scarcity of oceanographic data in the region, especially at high latitudes in the winter months. This study will provide new and significant oceanographic data on temperature and salinity profiles in to further the understanding of the dynamics of the upper water column of west Antarctic Peninsula continental shelf waters. Outreach activities include website development and an association with a marine education program at the Monterrey Bay Aquarium Research Institute.", "east": -61.4786, "geometry": "POINT(-64.87805 -60.19425)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "Not provided; R/V LMG", "locations": null, "north": -52.7602, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Costa, Daniel; Hofmann, Eileen; Goebel, Michael; Crocker, Daniel; Sidell, Bruce; Klinck, John M.", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.6283, "title": "Habitat Utilization of Southern Ocean Seals: Foraging Behavior of Crabeater and Elephant Seals Using Novel Methods of Oceanographic Data Collection", "uid": "p0000082", "west": -68.2775}, {"awards": "0338137 Anderson, John; 0338371 Hallet, Bernard", "bounds_geometry": "POLYGON((-74.59492 -45.98986,-74.072309 -45.98986,-73.549698 -45.98986,-73.027087 -45.98986,-72.504476 -45.98986,-71.981865 -45.98986,-71.459254 -45.98986,-70.936643 -45.98986,-70.414032 -45.98986,-69.891421 -45.98986,-69.36881 -45.98986,-69.36881 -46.835236,-69.36881 -47.680612,-69.36881 -48.525988,-69.36881 -49.371364,-69.36881 -50.21674,-69.36881 -51.062116,-69.36881 -51.907492,-69.36881 -52.752868,-69.36881 -53.598244,-69.36881 -54.44362,-69.891421 -54.44362,-70.414032 -54.44362,-70.936643 -54.44362,-71.459254 -54.44362,-71.981865 -54.44362,-72.504476 -54.44362,-73.027087 -54.44362,-73.549698 -54.44362,-74.072309 -54.44362,-74.59492 -54.44362,-74.59492 -53.598244,-74.59492 -52.752868,-74.59492 -51.907492,-74.59492 -51.062116,-74.59492 -50.21674,-74.59492 -49.371364,-74.59492 -48.525988,-74.59492 -47.680612,-74.59492 -46.835236,-74.59492 -45.98986))", "dataset_titles": "Expedition data of NBP0505; Expedition data of NBP0703; NBP0505 CTD data; NBP0505 sediment core locations", "datasets": [{"dataset_uid": "002609", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0505", "url": "https://www.rvdata.us/search/cruise/NBP0505"}, {"dataset_uid": "002642", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0703", "url": "https://www.rvdata.us/search/cruise/NBP0703"}, {"dataset_uid": "601362", "doi": "10.15784/601362", "keywords": "Chile; Fjord; Marine Geoscience; NBP0505; R/v Nathaniel B. Palmer; Sample/collection Description; Sample/Collection Description; Sediment Core; Sediment Corer; Station List", "people": "Anderson, John; Wellner, Julia", "repository": "USAP-DC", "science_program": null, "title": "NBP0505 sediment core locations", "url": "https://www.usap-dc.org/view/dataset/601362"}, {"dataset_uid": "601363", "doi": "10.15784/601363", "keywords": "Chile; CTD; CTD Data; Depth; Fjord; NBP0505; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Wellner, Julia; Anderson, John", "repository": "USAP-DC", "science_program": null, "title": "NBP0505 CTD data", "url": "https://www.usap-dc.org/view/dataset/601363"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project examines the role of glacier dynamics in glacial sediment yields. The results will shed light on how glacial erosion influences both orogenic processes and produces sediments that accumulate in basins, rich archives of climate variability. Our hypothesis is that erosion rates are a function of sliding speed, and should diminish sharply as the glacier\u0027s basal temperatures drop below the melting point. To test this hypothesis, we will determine sediment accumulation rates from seismic studies of fjord sediments for six tidewater glaciers that range from fast-moving temperate glaciers in Patagonia to slow-moving polar glaciers on the Antarctic Peninsula. Two key themes are addressed for each glacier system: 1) sediment yields and erosion rates by determining accumulation rates within the fjords using seismic profiles and core data, and 2) dynamic properties and basin characteristics of each glacier in order to seek an empirical relationship between glacial erosion rates and ice dynamics. The work is based in Patagonia and the Antarctic Peninsula, ideal natural laboratories for these purposes because the large latitudinal range provides a large range of precipitation and thermal regimes over relatively homogeneous lithologies and tectonic settings. Prior studies of these regions noted significant decreases in glaciomarine sediment accumulations in the fjords to the south. As well, the fjords constitute accessible and nearly perfect natural sediment traps.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this study include inter-disciplinary collaboration with Chilean glaciologists and marine geologists, support for one postdoctoral and three doctoral students, inclusion of undergraduates in research, and outreach to under-represented groups in Earth sciences and K-12 educators. The results of the project will also contribute to a better understanding of the linkages between climate and evolution of all high mountain ranges.", "east": -69.36881, "geometry": "POINT(-71.981865 -50.21674)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP; Penguin Glacier", "locations": null, "north": -45.98986, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, John; Hallet, Bernard; Wellner, Julia", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -54.44362, "title": "Collaborative Research: Controls on Sediment Yields from Tidewater Glaciers from Patagonia to Antarctica", "uid": "p0000821", "west": -74.59492}, {"awards": "9614028 Dymond, Jack", "bounds_geometry": "POLYGON((-179.9993 -63.09006,-143.99946 -63.09006,-107.99962 -63.09006,-71.99978 -63.09006,-35.99994 -63.09006,-0.000100000000003 -63.09006,35.99974 -63.09006,71.99958 -63.09006,107.99942 -63.09006,143.99926 -63.09006,179.9991 -63.09006,179.9991 -64.490422,179.9991 -65.890784,179.9991 -67.291146,179.9991 -68.691508,179.9991 -70.09187,179.9991 -71.492232,179.9991 -72.892594,179.9991 -74.292956,179.9991 -75.693318,179.9991 -77.09368,143.99926 -77.09368,107.99942 -77.09368,71.99958 -77.09368,35.99974 -77.09368,-0.000100000000003 -77.09368,-35.99994 -77.09368,-71.99978 -77.09368,-107.99962 -77.09368,-143.99946 -77.09368,-179.9993 -77.09368,-179.9993 -75.693318,-179.9993 -74.292956,-179.9993 -72.892594,-179.9993 -71.492232,-179.9993 -70.09187,-179.9993 -68.691508,-179.9993 -67.291146,-179.9993 -65.890784,-179.9993 -64.490422,-179.9993 -63.09006))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002161", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9605"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "96-14028 Dymond This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three-year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component, a collaborative study by scientists from the Woods Hole Oceanographic Institution, Oregon State University, and the New Zealand Oceanographic Institution, concerns the export of particulate forms of carbon downward from the upper ocean. The observations will be obtained from an array of time- series sediment traps, and will be analyzed to quantify export fluxes from the Subtropical Front to the Ross Sea, over an 18- months period beginning the early austral summer of 1996. The measurement program will two annual phytoplankton blooms. The southern ocean provides a unique opportunity to investigate the processes controlling export flux in contrasting biogeochemical ocean zones demarcated by oceanic fronts. The temperature changes at the fronts coincide with gradients in nutrient concentrations and plankton ecology, resulting in a large latitudinal change in the ratio of calcium to silica taken up by the phytoplankton communities. This experiment will provide data on how the biological pump operates in the Southern Ocean and how it could potentially impact the level of atmospheric c arbon dioxide. The observed export fluxes of organic carbon, nitrogen, inorganic carbon, biogenic silica and alumina are central to the goals of the JGOFS program.", "east": 179.9991, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -63.09006, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dymond, Jack", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.09368, "title": "Latitudinal Variations of Particle Fluxes in the Southern Ocean: A Bottom Tethered Sediment Trap Array Experiment", "uid": "p0000636", "west": -179.9993}, {"awards": "0130525 Fraser, William", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0105", "datasets": [{"dataset_uid": "002605", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0105", "url": "https://www.rvdata.us/search/cruise/NBP0105"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The potential consequence of human impact on wildlife in Antarctica has been debated for many decades. Scientists, support staff and visitors in Antarctica may have an effect on the behavior and population dynamics of marine mammals and seabirds. Since the early 1970\u0027s, shipboard tourism has expanded to the point where it is timely to address the question, using a scientific research approach. The focus of this study is to examine the potential effect of tourist activities on the Adelie Penguins (Pygoscelis adeliae) in the Antarctic Peninsula. The topic has gathered the interest and opinions of those in private industry, the scientific community, government organizations and environmental groups. A key concern is that increases in these activities may eventually overcome the ability of research to address critical issues in a timely and biologically meaningful manner. The approach to understanding how tourism might affect Adelie Penguins must involve both a study of human activity and a study of natural variability in the physical environment. The ongoing Palmer Long Term Ecological Research program focuses on the ecosystem and its components and thus addresses the issues of natural variability. This project focuses on the human dimension and continues a tourist-monitoring program begun as a pilot project near Palmer Station. This site is in a geographic location that mirrors current patterns in tourism and tourist-wildlife interactions in the western Antarctic Peninsula. It also offers a setting that provides unique opportunities for human impacts research. This includes the presence of long-term databases that document environmental variability over multiple time and space scales in both marine and terrestrial habitats, and the ability to examine potential tourist impacts as part of controlled experiments. The results of the study will have important implications to understanding interactions between climate change and ecosystem response, and for detecting, mitigating and managing the consequences of human activities such as tourism.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Fraser, William; Smith, Raymond", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Monitoring the Human Impact and Environmental Variability on Adelie Penguins at Palmer Station, Antarctica", "uid": "p0000819", "west": null}, {"awards": "9815961 Bengtson, John", "bounds_geometry": "POLYGON((-179.99905 -43.56728,-143.99915 -43.56728,-107.99925 -43.56728,-71.99935 -43.56728,-35.99945 -43.56728,0.000450000000001 -43.56728,36.00035 -43.56728,72.00025 -43.56728,108.00015 -43.56728,144.00005 -43.56728,179.99995 -43.56728,179.99995 -47.058498,179.99995 -50.549716,179.99995 -54.040934,179.99995 -57.532152,179.99995 -61.02337,179.99995 -64.514588,179.99995 -68.005806,179.99995 -71.497024,179.99995 -74.988242,179.99995 -78.47946,144.00005 -78.47946,108.00015 -78.47946,72.00025 -78.47946,36.00035 -78.47946,0.000450000000001 -78.47946,-35.99945 -78.47946,-71.99935 -78.47946,-107.99925 -78.47946,-143.99915 -78.47946,-179.99905 -78.47946,-179.99905 -74.988242,-179.99905 -71.497024,-179.99905 -68.005806,-179.99905 -64.514588,-179.99905 -61.02337,-179.99905 -57.532152,-179.99905 -54.040934,-179.99905 -50.549716,-179.99905 -47.058498,-179.99905 -43.56728))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001997", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9909"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9815961 BENGTSON The pack ice region surrounding Antarctica contains at least fifty percent of the world\u0027s population of seals, comprising about eighty percent of the world\u0027s total pinniped biomass. As a group, these seals are among the dominant top predators in Southern Ocean ecosystems, and the fluctuation in their abundance, growth patterns, life histories, and behavior provide a potential source of information about environmental variability integrated over a wide range of spatial and temporal scales. This proposal was developed as part of the international Antarctic Pack Ice Seals (APIS) program, which is aimed to better understand the ecological relationships between the distribution of pack ice seals and their environment. During January-February, 2000, a research cruise through the pack ice zone of the eastern Ross Sea and western Amundsen Sea will be conducted to survey and sample along six transects perpendicular to the continental shelf. Each of these transects will pass through five environmental sampling strata: continental shelf zone, Antarctic slope front, pelagic zone, the ice edge front, and the open water outside the pack ice zone. All zones but open water will be ice-covered to some degree. Surveys along each transect will gather data on bathymetry, hydrography, sea ice dynamics and characteristics, phytoplankton and ice algae stocks, prey species (e.g., fish, cephalopods and euphausiids), and seal distribution, abundance and diet. This physical and trophic approach to investigating ecological interactions among pack ice seals, prey and the physical environment will allow the interdisciplinary research team to test the hypothesis that there are measurable physical and biological features in the Southern Ocean that result in area of high biological activity by upper trophic level predators. Better insight into the interplay among pack ice seals and biological and physical features of Antarctic marine ecosystems will allow for a better prediction of fluctuation in seal population in the context of environmental change.", "east": 179.99995, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56728, "nsf_funding_programs": null, "paleo_time": null, "persons": "Bengtson, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.47946, "title": "Antarctic Pack Ice Seals: Ecological Interactions with Prey and the Environment", "uid": "p0000614", "west": -179.99905}, {"awards": "9910122 Martinson, Douglas", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG0106; Expedition data of LMG0205", "datasets": [{"dataset_uid": "001757", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0205"}, {"dataset_uid": "002703", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0205", "url": "https://www.rvdata.us/search/cruise/LMG0205"}, {"dataset_uid": "002695", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0106", "url": "https://www.rvdata.us/search/cruise/LMG0106"}, {"dataset_uid": "002697", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0106", "url": "https://www.rvdata.us/search/cruise/LMG0106"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is a contribution to a coordinated attempt to understand the interactions of biological and physical dynamics by developing mechanistic links between the evolution of the antarctic winter ice and snow cover, and biological habitat variability, through modeling the optical properties of the environment. The work will be carried out in the context of the Southern Ocean Experiment of the Global Ocean Ecosystem Dynamics Study (Globec), a large, multi-investigator study of the winter survival strategy of krill under the antarctic sea ice. The optical properties of snow and sea ice evolve through the winter and vary greatly both spectrally and spatially. These properties are an important element of the physical environment that strongly influences both the distribution of and the resources available to antarctic krill. The intensity of incident radiant energy and its distribution within the snow, ice, and water column environment, and the linked physical, optical, chemical, and biological processes that modulate its distribution are generally known but poorly quantified. The optical properties of snow and ice also influence snow algae, ice algae, and water column productivity, as well as visibility for both predator and prey. Furthermore, optical properties play an essential role in satellite observations as proxy indicators of geophysical sea ice parameters which permit local observations to be more accurately extrapolated in space and time, thus providing regional coverage that would otherwise not be possible. What is proposed is the deployment of an array of instrumented ice beacons, augmented by periodic ship-based and satellite observations, along with theoretical studies to create improved quantitative models with which to follow the temporal and spatial evolution of this snow and ice marine ecosystem. The specific objective is to develop a thermodynamic sea ice/ecosystem model through coupling of existing components in order to test our understanding of the system, determine its sensitivities, and to provide an organizing mechanism for integrating the Southern Ocean Globec observations. ***", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Costa, Daniel", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Optical Environmental of the Western Antarctic Peninsula (WAP) Region", "uid": "p0000865", "west": null}, {"awards": "9615342 Neale, Patrick", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9809", "datasets": [{"dataset_uid": "002720", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9809", "url": "https://www.rvdata.us/search/cruise/LMG9809"}, {"dataset_uid": "002719", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9809", "url": "https://www.rvdata.us/search/cruise/LMG9809"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Neale 9615342 Increases in ultraviolet-B radiation (UV-B, 280-320) associated with the Antarctic ozone hole have been shown to inhibit the photosynthesis of phytoplankton, but the overall effect on water column production is still a matter of debate and continued investigation. Investigations have also revealed that even at \"normal\" levels of Antarctic stratospheric ozone, UV-B and UV-A (320-400 nm) appear to have strong effects on water column production. The role of UV in the ecology of phytoplankton primary production has probably been underappreciated in the past and could be particularly important to the estimation of primary production in the presence of vertical mixing. This research focuses on quantifying UV effects on photosynthesis of Antarctic phytoplankton by defining biological weighting functions for UV-inhibition. In the past, techniques were developed to describe photosynthesis as a function of UV and visible irradiance using laboratory cultures. Further experimentation with natural assemblages from McMurdo Station in Antarctica showed that biological weighting functions are strongly related to light history. Most recently, measurements in the open waters of the Southern Ocean confirmed that there is substantial variability in the susceptibility of phytoplankton assemblages to UV. It was also discovered that inhibition of photosynthesis in Antarctic phytoplankton got progressively worse on the time scale of hours, with no evidence of recovery. Even under benign conditions, losses of photosynthetic capability persisted unchanged for several hours. This was in contrast with laboratory cultures and some natural assemblages which quickly attained a steady- state rate of photosynthesis during exposure to UV, reflecting a balance between damage and recovery processes. Slow reversal of UV-induced damage has profound consequences for water-column photosynthesis, especially during vertical mixing. Results to date have been used to model th e influence of UV, ozone depletion and vertical mixing on photosynthesis in Antarctic waters. Data indicate that normal levels of UV can have a significant impact on natural phytoplankton and that the effects can be exacerbated by ozone depletion as well as vertical mixing. Critical questions remain poorly resolved, however, and these are the focus of the present proposal. New theoretical and experimental approaches will be used to investigate UV responses in both the open waters of the Weddell-Scotia confluence and coastal waters near Palmer Station. In particular, measurements will be made of the kinetics of UV inhibition and recovery on time scales ranging from minutes to days. Variability in biological weighting functions between will be calculated for pelagic and coastal phytoplankton in the Southern Ocean. The results will provide absolute estimates of photosynthesis under in situ, as well as under altered, UV irradiance; broaden the range of assemblages for which biological weighting functions have been determined; and clarify how kinetics of inhibition and recovery should be represented in mixed layer models.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mopper, Kenneth; Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "New Approaches to Measuring and Understanding the Effects of Ultraviolet Radiation on Photosynthesis by Antarctic Phytoplankton", "uid": "p0000871", "west": null}, {"awards": "0338248 Takahashi, Taro", "bounds_geometry": "POLYGON((-68.0051 -52.7573,-67.35191 -52.7573,-66.69872 -52.7573,-66.04553 -52.7573,-65.39234 -52.7573,-64.73915 -52.7573,-64.08596 -52.7573,-63.43277 -52.7573,-62.77958 -52.7573,-62.12639 -52.7573,-61.4732 -52.7573,-61.4732 -53.96927,-61.4732 -55.18124,-61.4732 -56.39321,-61.4732 -57.60518,-61.4732 -58.81715,-61.4732 -60.02912,-61.4732 -61.24109,-61.4732 -62.45306,-61.4732 -63.66503,-61.4732 -64.877,-62.12639 -64.877,-62.77958 -64.877,-63.43277 -64.877,-64.08596 -64.877,-64.73915 -64.877,-65.39234 -64.877,-66.04553 -64.877,-66.69872 -64.877,-67.35191 -64.877,-68.0051 -64.877,-68.0051 -63.66503,-68.0051 -62.45306,-68.0051 -61.24109,-68.0051 -60.02912,-68.0051 -58.81715,-68.0051 -57.60518,-68.0051 -56.39321,-68.0051 -55.18124,-68.0051 -53.96927,-68.0051 -52.7573))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001572", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0603"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This proposal is for the continuation and expansion of an underway program on the R/V Laurence M. Gould to measure dissolved carbon dioxide gas (pCO2) along with occasional total carbon dioxide (TCO2) in surface waters on transects of Drake Passage. The added observations include dissolved oxygen, as well as nutrient and carbon-13. The proposed work is similar to the underway measurement program made aboard R/V Nathaniel B. Palmer, and complements similar surface temperature and current data.\u003cbr/\u003eThe Southern Ocean is an important component of the global carbon budget. Low surface temperatures with consequently low vertical stability, ice formation, and high winds produce a very active environment for the exchange of gaseous carbon dioxide between the atmospheric and oceanic reservoirs. The Drake Passage is the narrowest point through which the Antarctic Circumpolar Current and its associated fronts must pass, and is the most efficient location for the measurement of latitudinal gradients of gas exchange. The generated time series will contribute towards two scientific goals: the quantification of the spatial and temporal variability and trends of surface carbon dioxide, oxygen, nutrients and C-13, and an understanding of the dominant processes that contribute to the observed variability.", "east": -61.4732, "geometry": "POINT(-64.73915 -58.81715)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7573, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Takahashi, Taro", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.877, "title": "Collaborative Research: Processes Driving Spatial and Temporal Variability of Surface pCO2 in the Drake Passage", "uid": "p0000572", "west": -68.0051}, {"awards": "9814383 Domack, Eugene", "bounds_geometry": "POLYGON((-70.90625 -52.35392,-69.456459 -52.35392,-68.006668 -52.35392,-66.556877 -52.35392,-65.107086 -52.35392,-63.657295 -52.35392,-62.207504 -52.35392,-60.757713 -52.35392,-59.307922 -52.35392,-57.858131 -52.35392,-56.40834 -52.35392,-56.40834 -53.615031,-56.40834 -54.876142,-56.40834 -56.137253,-56.40834 -57.398364,-56.40834 -58.659475,-56.40834 -59.920586,-56.40834 -61.181697,-56.40834 -62.442808,-56.40834 -63.703919,-56.40834 -64.96503,-57.858131 -64.96503,-59.307922 -64.96503,-60.757713 -64.96503,-62.207504 -64.96503,-63.657295 -64.96503,-65.107086 -64.96503,-66.556877 -64.96503,-68.006668 -64.96503,-69.456459 -64.96503,-70.90625 -64.96503,-70.90625 -63.703919,-70.90625 -62.442808,-70.90625 -61.181697,-70.90625 -59.920586,-70.90625 -58.659475,-70.90625 -57.398364,-70.90625 -56.137253,-70.90625 -54.876142,-70.90625 -53.615031,-70.90625 -52.35392))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001985", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0003"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to study the region recently occupied by the Larsen Ice Shelf in the Antarctic Peninsula. Over the last 10 years, scientists have observed a dramatic decay and disintegration of floating ice shelves along the northern end of the Antarctic Peninsula. Meteorological records and satellite observations indicate that this catastrophic decay is related to regional warming of nearly 3 degrees C in the last 50 years. While such retreat of floating ice shelves is unprecedented in historic records, current understanding of the natural variability of ice shelf systems over the last few thousand years is not understood well. This award supports a program of marine geologic research directed at filling this knowledge gap by developing an understanding of the dynamics of the northern Larsen Ice Shelf during the Holocene epoch (the last 10,000 years). The Larsen Ice Shelf is located in the NW Weddell Sea along the eastern side of the Antarctic Peninsula and is currently undergoing a rapid, catastrophic retreat as documented by satellite imagery over the past five years. While the region of the northern Antarctic Peninsula has experienced a pronounced warming trend over the last 40 years, the links between this warming and global change (i.e. greenhouse warming) are not obvious. Yet the ice shelf is clearly receding at a rate unprecedented in historic time, leaving vast areas of the seafloor uncovered and in an open marine setting. This project will collect a series of short sediment cores within the Larsen Inlet and in areas that were at one time covered by the Larsen Ice Shelf. By applying established sediment and fossil criteria to the cores we hope to demonstrate whether the Larsen Ice Shelf has experienced similar periods of retreat and subsequent advance within the last 10,000 years. Past work in various regions of the Antarctic has focused on depositional models for ice shelves that allow one to discern the timing of ice shelf retreat/advance in areas of the Ross Sea, Antarctic Peninsula, and Prydz Bay. This research will lead to a much improved understanding of the dynamics of ice shelf systems and their role in past and future climate oscillations.", "east": -56.40834, "geometry": "POINT(-63.657295 -58.659475)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35392, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.96503, "title": "Paleohistory of the Larsen Ice Shelf: Evidence from the Marine Record", "uid": "p0000619", "west": -70.90625}, {"awards": "0636975 Sweeney, Colm", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG0909", "datasets": [{"dataset_uid": "002721", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0909", "url": "https://www.rvdata.us/search/cruise/LMG0909"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The proposed project will expand the suite of observations and lengthen the existing time series of underway surface dissolved carbon dioxide (pCO2) measurements transects across the Drake Passage on the R/VIB L.M. Gould. The additional observations include oxygen, nutrients and total CO2 (TCO2) concentrations, and the 13C to 12C ratio of TCO2. The continued and expanded time series will contribute towards two main scientific goals: the quantification of the spatial and temporal variability and the trends of surface carbon dioxide species in four major water mass regimes in the Drake Passage, and the understanding of the dominant processes and changes in those processes that contribute to the variability in surface pCO2 and the resulting air-sea flux of CO2 in the Drake Passage. The expanded program will also include the analysis of the 14C/12C of TCO2 and the specific study of the observations on one short wintertime cruise, with the objective of testing the hypothesis that the dissolved carbon dioxide in surface waters of the Drake Passage is determined by the degree of winter mixing. This is of special significance in light of two scenarios that may be affecting the ventilation of Southern Ocean deep water now and in the future: a decrease in water column stratification with the observations of higher zonal winds, or an increase in stratification due to higher precipitation and warming from climate change. If winter mixing determines the mean annual pCO2 in the Drake Passage, the increasing trend in atmospheric pCO2 should have little effect on sea surface pCO2.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sweeney, Colm; Sweeney, Colm", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Surface pCO2 and the effects of Winter Time Overturning in the Drake Passage", "uid": "p0000872", "west": null}, {"awards": "9419605 Dunbar, Robert; 9896356 Dunbar, Robert", "bounds_geometry": "POLYGON((-180 -43.56493,-144.00001 -43.56493,-108.00002 -43.56493,-72.00003 -43.56493,-36.00004 -43.56493,-0.000049999999987 -43.56493,35.99994 -43.56493,71.99993 -43.56493,107.99992 -43.56493,143.99991 -43.56493,179.9999 -43.56493,179.9999 -47.023783,179.9999 -50.482636,179.9999 -53.941489,179.9999 -57.400342,179.9999 -60.859195,179.9999 -64.318048,179.9999 -67.776901,179.9999 -71.235754,179.9999 -74.694607,179.9999 -78.15346,143.99991 -78.15346,107.99992 -78.15346,71.99993 -78.15346,35.99994 -78.15346,-0.000050000000016 -78.15346,-36.00004 -78.15346,-72.00003 -78.15346,-108.00002 -78.15346,-144.00001 -78.15346,-180 -78.15346,-180 -74.694607,-180 -71.235754,-180 -67.776901,-180 -64.318048,-180 -60.859195,-180 -57.400342,-180 -53.941489,-180 -50.482636,-180 -47.023783,-180 -43.56493))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002094", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9807"}, {"dataset_uid": "002132", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9709"}, {"dataset_uid": "002154", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9606"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is an interdisciplinary study, titled Research on Ocean-Atmosphere Variability and Ecosystem Response in the Ross Sea (ROAVERRS), of atmospheric forcing, ocean hydrography, sea ice dynamics, primary productivity, and pelagic-benthic coupling in the southwestern Ross Sea, Antarctica. The primary goal is to examine how changes in aspects of the polar climate system, in this case wind and temperature, combine to influence marine productivity on a large antarctic continental shelf. In the Ross Sea, katabatic winds and mesocyclones influence the spatial and temporal distribution of sea ice as well as the upper ocean mixed layer depth, and thus control primary production within the sea ice as well as in the open water system. The structure, standing stock and productivity of bottom- dwelling biological communities are also linked to meteorological processes through interseasonal and interannual variations in horizontal and vertical fluxes of organic carbon produced in the upper ocean. Linkages among the atmospheric, oceanic, and biological systems will be investigated during a three-year field study of the southwestern Ross Sea ecosystem. Direct measurements will include regional wind and air temperatures derived from automatic weather stations; ice cover, ice movement, and sea surface temperatures derived from a variety of satellite-based sensors; hydrographic characteristics of the upper ocean and primary productivity in the ice and in the water derived from research cruises and satellite studies; vertical flux of organic material and water movement derived from oceanographic moorings containing sediment traps and current meters, and the abundance, distribution, and respiration rates of biological communities on the sea floor, derived from box cores, benthic photographs and shipboard incubations. Based on archived meteorological data, it is expected that the atmospheric variability during the study period will be such that changes in airflow pat terns and their influence on oceanographic and biological patterns can be monitored, and their direct and indirect linkages that are the focus of the research can be deduced. Results from this study will contribute to our knowledge of atmospheric and oceanic forcing of marine ecosystems, and lead to a better understanding of marine ecosystem response to climatic variations. ***", "east": 179.9999, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56493, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Dunbar, Robert", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -78.15346, "title": "Research on Ocean-Atmosphere Variability and Ecosystem Response in the Ross Sea (ROAVERRS)", "uid": "p0000635", "west": -180.0}, {"awards": "0739483 Nowacek, Douglas", "bounds_geometry": "POLYGON((-68.0013 -52.7592,-67.34925 -52.7592,-66.6972 -52.7592,-66.04515 -52.7592,-65.3931 -52.7592,-64.74105 -52.7592,-64.089 -52.7592,-63.43695 -52.7592,-62.7849 -52.7592,-62.13285 -52.7592,-61.4808 -52.7592,-61.4808 -53.99669,-61.4808 -55.23418,-61.4808 -56.47167,-61.4808 -57.70916,-61.4808 -58.94665,-61.4808 -60.18414,-61.4808 -61.42163,-61.4808 -62.65912,-61.4808 -63.89661,-61.4808 -65.1341,-62.13285 -65.1341,-62.7849 -65.1341,-63.43695 -65.1341,-64.089 -65.1341,-64.74105 -65.1341,-65.3931 -65.1341,-66.04515 -65.1341,-66.6972 -65.1341,-67.34925 -65.1341,-68.0013 -65.1341,-68.0013 -63.89661,-68.0013 -62.65912,-68.0013 -61.42163,-68.0013 -60.18414,-68.0013 -58.94665,-68.0013 -57.70916,-68.0013 -56.47167,-68.0013 -55.23418,-68.0013 -53.99669,-68.0013 -52.7592))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001467", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1003"}, {"dataset_uid": "001483", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0905"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The krill surplus hypothesis argues that the near-extirpation of baleen whales from Antarctic waters during much the twentieth century led to significant changes in the availability of krill for other predators. Over the past decade, however, overall krill abundance has decreased by over an order of magnitude around the Antarctic Peninsula, in part due to physical forces, including the duration and extent of winter sea ice cover. Krill predators are vulnerable to variability in prey and have been shown to alter their demography in response to changes in prey availability This research will use novel tagging technology combined with traditional fisheries acoustics methods to quantify the prey consumed by a poorly understood yet ecologically integral and recovering krill predator in the Antarctic, the humpback whale (Megaptera novaeangliae). It also will use a combination of advanced non-invasive tag technology to study whale behavior concurrent with hydro-acoustic techniques to map krill aggregations. The project will (1) provide direct and quantitative estimates of krill consumption rates by humpback whales and incorporate these into models for the management of krill stocks and the conservation of the Antarctic marine ecosystem; (2) provide information integral to understanding predator-prey ecology and trophic dynamics, i.e., if/how baleen whales affect the distribution and behavior of krill and/or other krill predators; (3) add significantly to the knowledge of the diving behavior and foraging ecology of baleen whales in the Antarctic; and (4) develop new geospatial tools for the construction of multi-trophic level models that account for physical as well as biological data. \u003cbr/\u003e\u003cbr/\u003eBroader Impacts: Whales are assumed to be a major predator on Antarctic krill, yet there is little understanding of how whales utilize this resource. This knowledge is critical to addressing both bottom-up and top-down questions, e.g., how climate change may affect whales or how whales may affect falling krill abundances. This program will integrate research and education by providing opportunities for undergraduate and graduate students as well as postdoctoral researchers at Duke University, the Florida State University and the University of Massachusetts at Boston. This project will also seek to integrate interactive learning through real time, seasonal and curriculum development in collaboration with the National Geographic Society as well as at the participating universities and local schools in those communities.", "east": -61.4808, "geometry": "POINT(-64.74105 -58.94665)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP; R/V LMG", "locations": null, "north": -52.7592, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Nowacek, Douglas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.1341, "title": "Collaborative Research: The Ecological Role of a Poorly Studied Antarctic Krill Predator: The Humpback Whale, Megaptera Novaeangliae", "uid": "p0000529", "west": -68.0013}, {"awards": "9816226 Chereskin, Teresa", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9908", "datasets": [{"dataset_uid": "002691", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9908", "url": "https://www.rvdata.us/search/cruise/LMG9908"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This proposed work concerns the development and maintenance of a shipboard acoustic Doppler current profiler (ADCP) program on board the RVIB Nathaniel B. Palmer and the research vessel Laurence M. Gould, operated by the United States Antarctic Program. The objective is to generate a quality-controlled data set on upper ocean current velocities in a sparsely sampled and remote region, yet one that plays an important role in the global ocean circulation. Further goals are to develop the underway data collection program so that it can be maintained with a minimum of personnel and resources, and that the observations become publicly available in a timely manner. Long-term science objectives are to measure the seasonal and interannual variability of upper ocean currents within the Drake Passage, to combine this information with similar temperature observations to study the variability in the heat exchange, and to characterize the velocity structure in the Southern Ocean on a variety of time and space scales.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Chereskin, Teresa", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Shipboard Acoustic Doppler Current Profiling on R/V Nathaniel B. Palmer and R/V Lawrence M. Gould", "uid": "p0000862", "west": null}, {"awards": "9727077 Smith, Kenneth", "bounds_geometry": "POLYGON((-70.907166 -52.348,-69.6496994 -52.348,-68.3922328 -52.348,-67.1347662 -52.348,-65.8772996 -52.348,-64.619833 -52.348,-63.3623664 -52.348,-62.1048998 -52.348,-60.8474332 -52.348,-59.5899666 -52.348,-58.3325 -52.348,-58.3325 -53.600917,-58.3325 -54.853834,-58.3325 -56.106751,-58.3325 -57.359668,-58.3325 -58.612585,-58.3325 -59.865502,-58.3325 -61.118419,-58.3325 -62.371336,-58.3325 -63.624253,-58.3325 -64.87717,-59.5899666 -64.87717,-60.8474332 -64.87717,-62.1048998 -64.87717,-63.3623664 -64.87717,-64.619833 -64.87717,-65.8772996 -64.87717,-67.1347662 -64.87717,-68.3922328 -64.87717,-69.6496994 -64.87717,-70.907166 -64.87717,-70.907166 -63.624253,-70.907166 -62.371336,-70.907166 -61.118419,-70.907166 -59.865502,-70.907166 -58.612585,-70.907166 -57.359668,-70.907166 -56.106751,-70.907166 -54.853834,-70.907166 -53.600917,-70.907166 -52.348))", "dataset_titles": "Expedition Data; Expedition data of LMG0002; Expedition data of LMG0005", "datasets": [{"dataset_uid": "002670", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0002", "url": "https://www.rvdata.us/search/cruise/LMG0002"}, {"dataset_uid": "001964", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0010"}, {"dataset_uid": "002667", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0005", "url": "https://www.rvdata.us/search/cruise/LMG0005"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9727077 SMITH The annual expansion and contraction of ice cover in the Southern Ocean is the largest seasonal process in the World Ocean. This seasonal variability in ice cover creates extensive fluctuations in primary production, which heavily impacts pelagic and benthic communities. This research will initiate a long time-series study of the water column and sea floor using long-term, autonomous monitoring and sampling systems developed for use in the Antarctic. The study will be located in Post Foster, Deception Island, which supports a pelagic and benthic fauna representative of the Antarctic coastal zone and experiences seasonal ice cover. A bottom-moored, upward-looking acoustic instrument will be deployed on the sea floor for a period of one year to monitor the vertical distribution, abundance and biomass of acoustically-detectable macrozooplankton and micronekton in the water column. Collections will be made over this period using a newly-developed vertically-profiling pump sampling. Simultaneously, a time-lapse camera system will be moored on the sea floor to monitor the spatial distribution, sizes and movements of the epibenthic megafauna component of the benthic community. The instrumentation development will allow the research project to focus on the effect of the seasonal sea ice cycle on the distribution, abundance and biomass of the macrozooplankton and micronekton in the water column. Similar questions on the distribution, abundance, size and movements of the epibenthic megafauna will be addressed. Results from this study will provide a valuable data base for the evaluation of the pelagic and benthic community responses to seasonal variability in the Southern Ocean.", "east": -58.3325, "geometry": "POINT(-64.619833 -58.612585)", "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.348, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Kenneth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.87717, "title": "Influence of Seasonal Ice Cover on Pelagic and Benthic Communities: Long Time-Series Studies", "uid": "p0000608", "west": -70.907166}, {"awards": "0837988 Steig, Eric", "bounds_geometry": "POLYGON((-180 -65,-144 -65,-108 -65,-72 -65,-36 -65,0 -65,36 -65,72 -65,108 -65,144 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.5,-180 -85,-180 -82.5,-180 -80,-180 -77.5,-180 -75,-180 -72.5,-180 -70,-180 -67.5,-180 -65))", "dataset_titles": "West Antarctica Ice Core and Climate Model Data", "datasets": [{"dataset_uid": "609536", "doi": "10.7265/N5QJ7F8B", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; WAIS Divide", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": null, "title": "West Antarctica Ice Core and Climate Model Data", "url": "https://www.usap-dc.org/view/dataset/609536"}], "date_created": "Fri, 30 Apr 2010 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). \u003cbr/\u003e\u003cbr/\u003eThis award supports a project to reconstruct the past physical and chemical climate of Antarctica, with an emphasis on the region surrounding the Ross Sea Embayment, using \u003e60 ice cores collected in this region by US ITASE and by Australian, Brazilian, Chilean, and New Zealand ITASE teams. The ice core records are annually resolved and exceptionally well dated, and will provide, through the analyses of stable isotopes, major soluble ions and for some trace elements, instrumentally calibrated proxies for past temperature, precipitation, atmospheric circulation, chemistry of the atmosphere, sea ice extent, and volcanic activity. These records will be used to understand the role of solar, volcanic, and human forcing on Antarctic climate and to investigate the character of recent abrupt climate change over Antarctica in the context of broader Southern Hemisphere and global climate variability. The intellectual merit of the project is that ITASE has resulted in an array of ice core records, increasing the spatial resolution of observations of recent Antarctic climate variability by more than an order of magnitude and provides the basis for assessment of past and current change and establishes a framework for monitoring of future climate change in the Southern Hemisphere. This comes at a critical time as global record warming and other impacts are noted in the Southern Ocean, the Antarctic Peninsula, and on the Antarctic ice sheet. The broader impacts of the project are that Post-doctoral and graduate students involved in the project will benefit from exposure to observational and modeling approaches to climate change research and working meetings to be held at the two collaborating institutions plus other prominent climate change institutions. The results are of prime interest to the public and the media Websites hosted by the two collaborating institutions contain climate change position papers, scientific exchanges concerning current climate change issues, and scientific contribution series.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Deuterium Isotopes; Deuterium Excess; Not provided; GROUND-BASED OBSERVATIONS; Wais Divide-project", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Antarctic Climate Reconstruction Utilizing the US ITASE Ice Core Array (2009- 2012)", "uid": "p0000180", "west": -180.0}, {"awards": "0538639 Waddington, Edwin", "bounds_geometry": "POLYGON((-112.1 -79.4,-112.09 -79.4,-112.08 -79.4,-112.07 -79.4,-112.06 -79.4,-112.05 -79.4,-112.04 -79.4,-112.03 -79.4,-112.02 -79.4,-112.01 -79.4,-112 -79.4,-112 -79.41,-112 -79.42,-112 -79.43,-112 -79.44,-112 -79.45,-112 -79.46,-112 -79.47,-112 -79.48,-112 -79.49,-112 -79.5,-112.01 -79.5,-112.02 -79.5,-112.03 -79.5,-112.04 -79.5,-112.05 -79.5,-112.06 -79.5,-112.07 -79.5,-112.08 -79.5,-112.09 -79.5,-112.1 -79.5,-112.1 -79.49,-112.1 -79.48,-112.1 -79.47,-112.1 -79.46,-112.1 -79.45,-112.1 -79.44,-112.1 -79.43,-112.1 -79.42,-112.1 -79.41,-112.1 -79.4))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 01 Apr 2010 00:00:00 GMT", "description": "0538639\u003cbr/\u003eWaddington\u003cbr/\u003eThis award supports a project to study the patterns of accumulation variation and microstructural properties near the WAIS Divide ice core site in a 2.5 km array of 20 m boreholes. Borehole Optical Stratigraphy (BOS) is a novel optical measurement system that detects annual-scale layers in firn that result from changes in firn microstructure, giving annual-scale records of how accumulation varied spatially over the last 40-50 years. Data from borehole optical stratigraphy can eventually be calibrated against other data on the microstructural parameters of firn to calibrate BOS\u0027s sensitivity to density, pore-volume, and pore-shape variations, and to show by proxy how these parameters vary in space across the survey area. Statistical analysis of layer-thickness and layer-brightness data will enable prediction of: 1) interannual accumulation variability, 2) variability in layer-thickness at decadal scales due to changing spatial patterns in accumulation and 3) variability in microstructure-driven metamorphism due to changing spatial patterns of microstructure. With these statistics in hand, a scientist measuring climatic shifts found in the WAIS Divide ice core will be able to determine the fraction by which signals they measure exceed the signal due to background accumulation variations. As an added benefit, while still in the field, we will determine a preliminary depth-age scale for the firn by optical layer-counting, to the depth of the deepest air-filled firn hole available. This will be a valuable result for core-drilling operations and for preliminary data-analysis on the core. In terms of broader impacts, this project will advance education by training a post-doctoral student in field techniques. The P.I. and the post-doctoral researcher will participate in an undergraduate seminar called \"What is Scientific Research?\", incorporating progress and results from this project. They will also communicate about their progress and field experience with a middle-school science and math class.", "east": -112.0, "geometry": "POINT(-112.05 -79.45)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS", "is_usap_dc": false, "keywords": "Spatial Variability; FIELD INVESTIGATION; Not provided; LABORATORY; Stratigraphy; Borehole Optical Stratigraphy; Optical Layer-Counting; Microstructure; Firn; Depth-Age-Model; Optical; WAIS Divide; FIELD SURVEYS; Accumulation", "locations": "WAIS Divide", "north": -79.4, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Fudge, T. J.; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.5, "title": "Spatial Variability in Firn Properties from Borehole Optical Stratigraphy at the Inland WAIS Core Site", "uid": "p0000237", "west": -112.1}, {"awards": "0741510 Yuan, Xiaojun", "bounds_geometry": "POLYGON((-180 -69,-172 -69,-164 -69,-156 -69,-148 -69,-140 -69,-132 -69,-124 -69,-116 -69,-108 -69,-100 -69,-100 -70,-100 -71,-100 -72,-100 -73,-100 -74,-100 -75,-100 -76,-100 -77,-100 -78,-100 -79,-108 -79,-116 -79,-124 -79,-132 -79,-140 -79,-148 -79,-156 -79,-164 -79,-172 -79,180 -79,178.5 -79,177 -79,175.5 -79,174 -79,172.5 -79,171 -79,169.5 -79,168 -79,166.5 -79,165 -79,165 -78,165 -77,165 -76,165 -75,165 -74,165 -73,165 -72,165 -71,165 -70,165 -69,166.5 -69,168 -69,169.5 -69,171 -69,172.5 -69,174 -69,175.5 -69,177 -69,178.5 -69,-180 -69))", "dataset_titles": "Temperature and salinity measurements collected using XBT, XCTD from the Oden and other platforms in the Southern Oceans from 2003-2008 (NODC Accession 0053045)", "datasets": [{"dataset_uid": "000214", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Temperature and salinity measurements collected using XBT, XCTD from the Oden and other platforms in the Southern Oceans from 2003-2008 (NODC Accession 0053045)", "url": "https://data.nodc.noaa.gov/cgi-bin/iso?id=gov.noaa.nodc:0053045"}], "date_created": "Sat, 20 Feb 2010 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe project goal is to investigate the ocean-atmosphere-ice (OAI) interactions in the Amundsen and Ross Seas during the austral summer of 2007-08 using hydrographic measurements (CTD and XBT) in conjunction with (1) ship-based observations and satellite-derived estimates of sea ice concentration, and (2) ship-based observations and re-analyses of meteorological variables. The major scientific objectives are as follows: (1) to examine upper ocean characteristics along three transects in the Amundsen Sea and two transects in the Ross Sea within the context of ice-atmosphere variability over the preceding winter-spring season and as compared to other years where data are available; (2) to determine if there is additional evidence of increased upwelling of warm Circumpolar Deep Water onto the shelf in the Amundsen Sea and/or increased freshening in the Ross Sea as has been inferred by previous, but limited, ocean surveys in these regions; and (3) to examine the spatial variability in ocean thermal structure along the ship\u0027s track (outside the transects) to provide greater regional context and to compare with ocean XBT data collected during Oden 2006-07. A repeated temperature survey between the Amundsen and Ross Sea is particularly invaluable, given that this sector is the regional center of the high latitude OAI response to ENSO, thus providing opportunity for examining and linking regional oceanic temporal variability to global climate variability. The research will improve our understanding of the high latitude OAI response to climate change, and provide the physical context for the observed biology and geochemistry (investigated by our colleagues. Our results will be made widely available through research publications and internet-available databases, and through the strong public outreach efforts of Lamont-Doherty Earth Observatory. The outreach efforts will help increase awareness and understanding of anthropogenic climate change, melting ice, and ecosystem alteration in the highly sensitive Antarctic.", "east": -100.0, "geometry": "POINT(-147.5 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -69.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Yuan, Xiaojun; Stammerjohn, Sharon", "platforms": "Not provided", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -79.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden: Ocean-Atmosphere-Ice Interactions and Changes", "uid": "p0000562", "west": 165.0}, {"awards": "0538627 Gill, John", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 08 Sep 2009 00:00:00 GMT", "description": "This proposal is focused on experimental studies of the thunderstorms electrodynamic coupling to the Earth\u0027s radiation belts through the upward lightning flashes that lead to ionospheric parameters variability, and the global lightning effects on climate. The intellectual merit of the proposed program lies in the importance of the electrodynamic coupling of lightning discharges to the overlying ionosphere and the radiation belts, both in terms of lightning-induced electron precipitation, and in terms of high altitude optical and gamma-ray emissions produced by energy originating in lightning discharges. Precipitation of the radiation belt particles by whistler waves launched by lightning discharges will be measured as associated localized and transient disturbances of the lower ionosphere, which are sensed remotely by means of their effect on the phase and amplitude of very low frequency (VLF) signals propagating in the Earth-ionosphere waveguide. The broader impacts of the proposed research program will include the development of new technologies of lightning detection, with few observation sites and on a global scale, which can then be implemented for the benefit of society, both in terms of agriculture, navigation and other ways in which lightning and thunderstorms may affect human life. The proposed program is a part of the international collaboration between the Antarctic Peninsula stations, as well as complements a similar set of measurements that are conducted by the Stanford University in the northern hemisphere under support from other sources. Coordinated measurements in both hemispheres are needed to study the geomagnetic conjugacy of the observed phenomena.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Inan, Umran", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "ELF/VLF Observations of Lightning Discharges, Whistler-mode waves and Electron Precipitation at Palmer Station, Antarctica.", "uid": "p0000687", "west": -180.0}, {"awards": "0125794 Price, P. Buford", "bounds_geometry": null, "dataset_titles": "Optical Logging for Dust and Microbes in Boreholes in Glacial Ice", "datasets": [{"dataset_uid": "609403", "doi": "10.7265/N59P2ZKB", "keywords": "Antarctica; Dust; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Microbiology; Optical Backscatter", "people": "Bay, Ryan", "repository": "USAP-DC", "science_program": null, "title": "Optical Logging for Dust and Microbes in Boreholes in Glacial Ice", "url": "https://www.usap-dc.org/view/dataset/609403"}], "date_created": "Wed, 29 Jul 2009 00:00:00 GMT", "description": "0125794\u003cbr/\u003ePrice\u003cbr/\u003e\u003cbr/\u003eThis award supports research in climatology, geosciences, and life in extreme environments to be carried out with a newly developed optical borehole logger. The logger fits into a fluid-filled borehole in glacial ice. It emits light at 370 nm in a horizontal plane in order to probe optical properties of particles embedded in the ice out to several meters from the borehole. After leaving the borehole, the light is partially absorbed and scattered by dust, biomolecules, or microbes. A fraction of the light is scattered back into the borehole and is detected by a system of seven phototubes, each of which collects light with high efficiency in a separate wavelength band. One of them collects light that scatters off of dust and air bubbles without wavelength shift, and serves as a dust logger. The other six are covered with notch filters that measure six different wavelength bands and measure the shape of the fluorescence spectrum of microbes and biomolecules. Thus, the same instrument serves as both a dust logger and a microbe logger. Applications include: 1) Precise chronologies and long-period solar variability. With a resolution of 1 to 2 cm for both GISP2 and Siple Dome, the logger will record annual dust maxima and evaluate claims of modulations of dust concentration with periods ranging from 11 yrs (the solar cycle) to 2300 yrs; 2) Volcanism and age-depth markers. Dozens of volcanic ash bands will be detectable and will serve as primary age-depth markers for other boreholes; 3) Microorganisms and biomolecules. The vertical distribution of living, dormant, and dead microbes can be logged, and searches for archaea and aeolian polyaromatic hydrocarbons can be made. The logging experiments will be carried out at Siple Dome and Dome C in Antarctica and at GISP2 and GRIP in Greenland.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS", "is_usap_dc": true, "keywords": "Ice Core Data; Not provided; Climate Research; Climate; FIELD INVESTIGATION; Climate Change; FIELD SURVEYS; LABORATORY; Paleoclimate; Ice Core; Volcanic", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Arctic Natural Sciences", "paleo_time": null, "persons": "Bay, Ryan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Optical Logging for Dust and Microbes in Boreholes in Glacial Ice", "uid": "p0000156", "west": null}, {"awards": "0439759 Ballard, Grant", "bounds_geometry": "POLYGON((-180 -60,-177.5 -60,-175 -60,-172.5 -60,-170 -60,-167.5 -60,-165 -60,-162.5 -60,-160 -60,-157.5 -60,-155 -60,-155 -61.76,-155 -63.52,-155 -65.28,-155 -67.04,-155 -68.8,-155 -70.56,-155 -72.32,-155 -74.08,-155 -75.84,-155 -77.6,-157.5 -77.6,-160 -77.6,-162.5 -77.6,-165 -77.6,-167.5 -77.6,-170 -77.6,-172.5 -77.6,-175 -77.6,-177.5 -77.6,180 -77.6,178.5 -77.6,177 -77.6,175.5 -77.6,174 -77.6,172.5 -77.6,171 -77.6,169.5 -77.6,168 -77.6,166.5 -77.6,165 -77.6,165 -75.84,165 -74.08,165 -72.32,165 -70.56,165 -68.8,165 -67.04,165 -65.28,165 -63.52,165 -61.76,165 -60,166.5 -60,168 -60,169.5 -60,171 -60,172.5 -60,174 -60,175.5 -60,177 -60,178.5 -60,-180 -60))", "dataset_titles": "Access to data; Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science; Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "datasets": [{"dataset_uid": "601443", "doi": "10.15784/601443", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Penguin; Ross Sea; Seabirds", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin banding data 1994-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601443"}, {"dataset_uid": "001368", "doi": "", "keywords": null, "people": null, "repository": "CADC", "science_program": null, "title": "Access to data", "url": "http://data.prbo.org/apps/penguinscience/AllData/mammals"}, {"dataset_uid": "601444", "doi": "10.15784/601444", "keywords": "Adelie Penguin; Antarctica; Biota; Demography; Mark-Recapture; Monitoring; Penguin; Ross Island", "people": "Ballard, Grant", "repository": "USAP-DC", "science_program": null, "title": "Adelie penguin resighting data 1997-2021 from the California Avian Data Center hosted by Point Reyes Bird Observatory Conservation Science", "url": "https://www.usap-dc.org/view/dataset/601444"}], "date_created": "Tue, 19 May 2009 00:00:00 GMT", "description": "This project is an international collaborative investigation of geographic structuring, founding of new colonies, and population change of Adelie penguins (Pygoscelis adelia) nesting on Ross and Beaufort islands, Antarctica. The long-term changes occurring at these colonies are representative of changes throughout the Ross Sea, where 30% of all Adelie penguins reside, and are in some way related to changing climate. The recent grounding of two very large icebergs against Ross and Beaufort islands, with associated increased variability in sea-ice extent, has provided an unparalleled natural experiment affecting wild, interannual swings in colony productivity, foraging effort, philopatry and recruitment. Results of this natural experiment can provide insights into the demography and geographic population structuring of this species, having relevance Antarctic-wide in understanding its future responses to climate change as well as interpreting its amazingly well known Holocene history. This ongoing study will continue to consider the relative importance of resources that constrain or enhance colony growth (nesting habitat, access to food); the aspects of natural history that are affected by exploitative or interference competition among neighboring colonies (breeding success, foraging effort); climatic factors that influence the latter, especially sea ice patterns; and behavioral mechanisms that influence colony growth as a function of initial size and location (emigration, immigration). An increased effort will focus on understanding factors that affect over-winter survival. The hypothesis is that the age structure of Cape Crozier has changed over the past thirty years and no longer reflects the smaller colonies nearby. Based on recent analyses, it appears that the Ross Island penguins winter in a narrow band of sea ice north of the Antarctic Circle (where daylight persists) and south of the southern boundary of the Antarctic Circumpolar Current (where food abounds). More extensive winter ice takes the penguins north of that boundary where they incur higher mortality. Thus, where a penguin winters may be due to the timing of its post-breeding departure (which differs among colonies), which affects where it first encounters sea ice on which to molt and where it will be transported by the growing ice field. Foraging effort and interference competition for food suggested as factors driving the geographic structuring of colonies. The research includes a census of known-age penguins, studies of foraging effort and overlap among colonies; and identification of the location of molting and wintering areas. Information will be related to sea-ice conditions as quantified by satellite images. Demographic and foraging-effort models will be used to synthesize results. The iceberg natural experiment is an unparalleled opportunity to investigate the demographics of a polar seabird and its response to climate change. The marked, interannual variability in apparent philopatry, with concrete data being collected on its causes, is a condition rarely encountered among studies of vertebrates. Broader impacts include collaborating with New Zealand and Italian researchers, involving high school teachers and students in the fieldwork and continuing a website to highlight results to both scientists and the general public.", "east": -155.0, "geometry": "POINT(-175 -68.8)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ballard, Grant", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "CADC; USAP-DC", "science_programs": null, "south": -77.6, "title": "COLLABORATIVE: Geographic Structure of Adelie Penguin Colonies - Demography of Population Change", "uid": "p0000068", "west": 165.0}, {"awards": "0438777 Fritts, David", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Correlative Antarctic and Inter-Hemispheric Dynamics Studies Using the MF Radar at Rothera", "datasets": [{"dataset_uid": "600040", "doi": "10.15784/600040", "keywords": "Antarctica; Atmosphere; Meteorology; Radar", "people": "Fritts, David", "repository": "USAP-DC", "science_program": null, "title": "Correlative Antarctic and Inter-Hemispheric Dynamics Studies Using the MF Radar at Rothera", "url": "https://www.usap-dc.org/view/dataset/600040"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "This proposal is to continue operation and scientific studies with the middle-frequency (MF, 1-30 MHz) mesospheric radar deployed at the British Antarctic station Rothera in 1996. This system is now a key site in the Antarctic MF radar chain near 68 deg. S, which includes also MF radars at Syowa (Japan) and Davis (Australia) stations. This radar comprises the winds component of a developing instrument suite for the mesosphere-thermosphere (MLT) studies at Rothera - a focus of the new BAS 5-year plan, which also includes the Fe temperature lidar (formerly at South Pole) and the mesopause airglow imager for gravity wave studies (formerly at Halley). The Rothera MF radar has just had its antennas and electronics upgraded to achieve better signal-to-noise ratio and more continuous measurements in height and time. The main focus of the proposed research is to extend the knowledge of the polar mesosphere dynamics. The instrument suite at Rothera is ideally positioned for correlative interhemispheric studies with northern hemisphere sites at Poker Flat, Alaska (65 deg. N) and ALOMAR, Norway (69 deg. N) having comparable instrumentation. Further research efforts performed with continued funding will focus on: (1) multi-instrument collaborative studies at Rothera to quantify as fully as possible the dynamics, structure, and variability of the MLT at that location, (2) multi-site (and multi-instrument) studies of large-scale dynamics and variability in the Antarctic (together with the radars and other instrumentation at Davis and Syowa), and (3) interhemispheric studies employing instruments (e.g., the Na resonance lidar and MF radar) at Poker Flat and ALOMAR. It is expected that these studies will lead to a more detailed understanding of (1) mean, tidal, and planetary wave structures at polar latitudes, (2) seasonal, inter-annual, and short-term variability of these structures, (3) hemispheric differences in the tidal and planetary wave structures arising from different source and wave interaction conditions, and (4) the relative influences of gravity waves in the two hemispheres. Such studies will also contribute more generally to an increased awareness of the role of high-latitude processes in global atmospheric dynamics and variability.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Fritts, David", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Correlative Antarctic and Inter-Hemispheric Dynamics Studies Using the MF Radar at Rothera", "uid": "p0000021", "west": -180.0}, {"awards": "0443403 Measures, Christopher; 0230445 Measures, Christopher; 0444040 Zhou, Meng", "bounds_geometry": "POLYGON((-63 -60.3,-62 -60.3,-61 -60.3,-60 -60.3,-59 -60.3,-58 -60.3,-57 -60.3,-56 -60.3,-55 -60.3,-54 -60.3,-53 -60.3,-53 -60.77,-53 -61.24,-53 -61.71,-53 -62.18,-53 -62.65,-53 -63.12,-53 -63.59,-53 -64.06,-53 -64.53,-53 -65,-54 -65,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-63 -64.53,-63 -64.06,-63 -63.59,-63 -63.12,-63 -62.65,-63 -62.18,-63 -61.71,-63 -61.24,-63 -60.77,-63 -60.3))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001663", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0402"}], "date_created": "Mon, 12 Jan 2009 00:00:00 GMT", "description": "The Shackleton Fracture Zone (SFZ) in the Drake Passage defines a boundary between low and high phytoplankton waters. West of Drake Passage, Southern Ocean waters south of the Polar Front and north of the Antarctic continent shelf have very low satellite-derived surface chlorophyll concentrations. Chlorophyll and mesoscale eddy kinetic energy are higher east of SFZ compared to values west of the ridge. In situ data from a 10-year survey of the region as part of the National Marine Fisheries Service\u0027s Antarctic Marine Living Resources program confirm the existence of a strong hydrographic and chlorophyll gradient in the region. An interdisciplinary team of scientists hypothesizes that bathymetry, including the 2000 m deep SFZ, influences mesoscale circulation and transport of iron leading to the observed phytoplankton patterns. To address this\u003cbr/\u003ehypothesis, the team proposes to examine phytoplankton and bacterial physiological states (including responses to iron enrichment) and structure of the plankton communities from virus to zooplankton, the concentration and distribution of Fe, Mn, and Al, and mesoscale flow patterns near the SFZ. Relationships between iron concentrations and phytoplankton characteristics will be examined in the context of the mesoscale transport of trace nutrients to determine how much of the observed variability in phytoplankton biomass can be attributed to iron supply, and to determine the most important sources of iron to pelagic waters east of the Drake Passage. The goal is to better understand how plankton productivity and community structure in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and limiting nutrient distributions.\u003cbr/\u003e\u003cbr/\u003eThe research program includes rapid surface surveys of chemical, plankton, and hydrographic properties complemented by a mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments. Distributions of manganese and aluminum will be determined to help distinguish aeolian, continental shelf and upwelling sources of iron. The physiological state of the phytoplankton will be monitored by active fluorescence methods sensitive to the effects of iron limitation. Mass concentrations of pigment, carbon and nitrogen will be obtained by analysis of filtered samples, cell size distributions by flow cytometry, and species identification by microscopy. Primary production and photosynthesis parameters (absorption, quantum yields, variable fluorescence) will be measured on depth profiles, during surface surveys and on bulk samples from enrichment experiments. Viruses and bacteria will be examined for abundances, and bacterial production will be assessed in terms of whether it is limited by either iron or organic carbon sources. The proposed work will improve our understanding of processes controlling distributions of iron and the response of plankton communities in the Southern Ocean. This proposal also includes an outreach component comprised of Research Experiences for Undergraduates (REU), Teachers Experiencing the Antarctic and Arctic (TEA), and the creation of an educational website and K-12 curricular modules based on the project.", "east": -53.0, "geometry": "POINT(-58 -62.65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": true, "keywords": "R/V LMG", "locations": null, "north": -60.3, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Measures, Christopher; Selph, Karen; Zhou, Meng", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.0, "title": "Collaborative Research: Plankton Community Structure and Iron Distribution in the Southern Drake Passage", "uid": "p0000585", "west": -63.0}, {"awards": "0636706 Sivjee, Gulamabas", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "NCAR Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) Data System ID# 5700 (full data link not provided)", "datasets": [{"dataset_uid": "000137", "doi": "", "keywords": null, "people": null, "repository": "NCAR", "science_program": null, "title": "NCAR Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) Data System ID# 5700 (full data link not provided)", "url": "http://cedarweb.hao.ucar.edu/"}], "date_created": "Thu, 23 Oct 2008 00:00:00 GMT", "description": "This project will provide for the continued operation and data analysis of an electro-optical remote sensing facility at South Pole Station. The facility will be used to examine 1) the source(s) and propagation of patches of enhanced plasma density in the F-region of the Antarctic ionosphere, 2) changes in the Antarctic E-region O/N2 ratio in the center of the night-sector of the auroral oval and compare the ratios with those found in the sun-aligned auroral arcs in the Polar Cap region, 3) Antarctic middle atmosphere disturbances generated by Stratospheric Warming Events (SWE), 4) quantitative characterization of the effects of solar variability on the temperature of the upper mesosphere region, 5) Antarctic thermospheric response to Solar Magnetic Cloud/Coronal Mass Ejection (SMC/CME) events, and 6) the effects of Joule heating on the thermodynamics of the Antarctic F-region. Data for all these studies will come from two sets of remote-sensing facilities at SPS: 1) Auroral emissions brightness measurements from the sun-synchronous Meridian Scanning Photon Counting Multichannel photometer; 2) Airglow and Auroral emission spectra recorded continuously during Austral winter at SPS with the high throughput, high resolution Infrared Michelson Interferometer as well as Visible - Near Infrared CCD spectrographs. \u003cbr/\u003e\u003cbr/\u003eMeridional variations in the brightness of F-region\u0027s auroral emissions provide the necessary data for investigations of the dynamics and IMF control, as well as the excitation mechanism(s), of the F-region patches. The brightness of auroral emissions from O and N relative to those from molecular species (O2 and N2) can be analyzed to assess, quantitatively, changes in the thermospheric composition. These data (from continuous (24 hours a day) measurements during the totally dark six months of each Austral winter at SPS) will be used to investigate the effects of solar-terrestrial disturbances on Antarctic thermospheric composition and thermodynamics, including response of the mesopause to solar cycle variations. Changes in airglow temperature (derived from OH and O2 bands), from different mesosphere/lower-thermosphere (MLT) heights, permit studies of the dynamical effects of Planetary, Tidal and Gravity waves propagating in the MLT regions as well as non-linear interactions among these waves. Coupling of different atmospheric regions over SPS, through enhanced gravity wave activities during SWE that lead to a precursor as Mesospheric cooling, will be investigated through the observed changes in MLT kinetic air temperature and density. \u003cbr/\u003e\u003cbr/\u003eThe project will enhance the infrastructure for research and education at Embry-Riddle Aeronautical University, bringing together the PI/Co-I and students from Departments of Physical Sciences and Aerospace Engineering. Graduate and undergraduate students will participate in modern research and software development.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Gulamabas, Sivjee; Azeem, Syed", "platforms": "Not provided", "repo": "NCAR", "repositories": "NCAR", "science_programs": null, "south": -90.0, "title": "Observations of Upper Atmospheric Energetics, Dynamics, and Long-Term Variations over the South Pole Station", "uid": "p0000292", "west": -180.0}, {"awards": "0636953 Saltzman, Eric", "bounds_geometry": "POINT(-148.82 -81.66)", "dataset_titles": "Carbonyl Sulfide Measurements in the Taylor Dome M3C1 Ice Core; Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core; Methyl Bromide Measurements in the Taylor Dome M3C1 Ice Core; Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica; Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core", "datasets": [{"dataset_uid": "609599", "doi": "10.7265/N5S75D8P", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Carbonyl Sulfide Measurements in the Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/609599"}, {"dataset_uid": "609598", "doi": "10.7265/N5X0650D", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Methyl Bromide Measurements in the Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/609598"}, {"dataset_uid": "609600", "doi": "10.7265/N5PG1PPB", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/609600"}, {"dataset_uid": "609356", "doi": "10.7265/N56W9807", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Williams, Margaret; Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Methyl Chloride Measurements from the Siple Dome A Deep Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609356"}, {"dataset_uid": "601361", "doi": "10.15784/601361", "keywords": "Antarctica; Carbonyl Sulfide; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/601361"}], "date_created": "Wed, 22 Oct 2008 00:00:00 GMT", "description": "Saltzman/0636953\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to measure methyl chloride, methyl bromide, and carbonyl sulfide in air extracted from Antarctic ice cores. Previous measurements in firn air and shallow ice cores suggest that the ice archive contains paleo-atmospheric signals for these gases. The goal of this study is to extend these records throughout the Holocene and into the last Glacial period to examine the behavior of these trace gases over longer time scales and a wider range of climatic conditions. These studies are exploratory, and both the stability of these trace gases and the extent to which they may be impacted by in situ processes will be assessed. This project will involve sampling and analyzing archived ice core samples from the Siple Dome, Taylor Dome, Byrd, and Vostok ice cores. The ice core samples will be analyzed by dry extraction, with gas chromatography/mass spectrometry with isotope dilution. The ice core measurements will generate new information about the range of natural variability of these trace gases in the atmosphere. The intellectual merit of this project is that this work will provide an improved basis for assessing the impact of anthropogenic activities on biogeochemical cycles, and new insight into the climatic sensitivity of the biogeochemical processes controlling atmospheric composition. The broader impact of this project is that there is a strong societal interest in understanding how man\u0027s activities impact the atmosphere, and how atmospheric chemistry may be altered by future climate change. The results of this study will contribute to the development of scenarios used for future projections of stratospheric ozone and climate change. In terms of human development, this project will support the doctoral dissertation of a graduate student in Earth System Science, and undergraduate research on polar ice core chemistry. This project will also contribute to the development of an Earth Sciences teacher training curriculum for high school teachers in the Orange County school system in collaboration with an established, NSF-sponsored Math and Science Partnership program (FOCUS).", "east": -148.82, "geometry": "POINT(-148.82 -81.66)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Antarctica; Methyl Bromide; Antarctic; Ice Core Gas Records; Ice Core Data; Carbonyl Sulfide; Methyl Chloride; Antarctic Ice Sheet; Siple Dome; Trace Gases; Ice Core Chemistry; Biogeochemical; Atmospheric Chemistry; West Antarctic Ice Sheet; LABORATORY; Ice Core; West Antarctica", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; Siple Dome; West Antarctica; West Antarctic Ice Sheet", "north": -81.66, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Saltzman, Eric; Aydin, Murat; Williams, Margaret", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core; Siple Dome Ice Core", "south": -81.66, "title": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores", "uid": "p0000042", "west": -148.82}, {"awards": "0228052 Kreutz, Karl", "bounds_geometry": "POLYGON((161.0434 -77.3002,161.241645 -77.3002,161.43989 -77.3002,161.638135 -77.3002,161.83638 -77.3002,162.034625 -77.3002,162.23287 -77.3002,162.431115 -77.3002,162.62936 -77.3002,162.827605 -77.3002,163.02585 -77.3002,163.02585 -77.3784846,163.02585 -77.4567692,163.02585 -77.5350538,163.02585 -77.6133384,163.02585 -77.691623,163.02585 -77.7699076,163.02585 -77.8481922,163.02585 -77.9264768,163.02585 -78.0047614,163.02585 -78.083046,162.827605 -78.083046,162.62936 -78.083046,162.431115 -78.083046,162.23287 -78.083046,162.034625 -78.083046,161.83638 -78.083046,161.638135 -78.083046,161.43989 -78.083046,161.241645 -78.083046,161.0434 -78.083046,161.0434 -78.0047614,161.0434 -77.9264768,161.0434 -77.8481922,161.0434 -77.7699076,161.0434 -77.691623,161.0434 -77.6133384,161.0434 -77.5350538,161.0434 -77.4567692,161.0434 -77.3784846,161.0434 -77.3002))", "dataset_titles": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "609399", "doi": "10.7265/N5FF3Q92", "keywords": "Antarctica; Borehole Temperature; Chemistry:ice; Chemistry:Ice; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Mass Balance; Paleoclimate; Physical Properties", "people": "Mayewski, Paul A.; Kreutz, Karl", "repository": "USAP-DC", "science_program": null, "title": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609399"}], "date_created": "Tue, 21 Oct 2008 00:00:00 GMT", "description": "This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit of the project. We plan to collect intermediate-length ice cores (100-200m) at four sites along transects in Taylor Valley and Wright Valley, and analyze each core at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). A suite of statistical techniques will be applied to the multivariate glaciochemical dataset to identify chemical associations and to calibrate the time-series records with available instrumental data. Broader impacts of the project include: 1) contributions to several ongoing interdisciplinary Antarctic research programs; 2) graduate and undergraduate student involvement in field, laboratory, and data interpretation activities; 3) use of project data and ideas in several UMaine courses and outreach activities; and 4) data dissemination through peer-reviewed publications, UMaine and other paleoclimate data archive websites, and presentations at national and international meetings.", "east": 163.02585, "geometry": "POINT(162.034625 -77.691623)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MC-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e HUMIDITY SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "Holocene; Climate Research; AWS Climate Data; Paleoclimate; Climate Variation; Dry Valleys; Wright Valley; Little Ice Age; Stable Isotopes; Glaciochemical; Ice Core; FIELD INVESTIGATION; Enso; Antarctic Oscillation; Climate; GPS; El Nino-Southern Oscillation; LABORATORY; Not provided; Climate Change; Ice Core Records; Antarctica; Taylor Valley; FIELD SURVEYS; Variability", "locations": "Antarctica; Dry Valleys; Taylor Valley; Wright Valley", "north": -77.3002, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Arcone, Steven; Mayewski, Paul A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.083046, "title": "Dry Valleys Late Holocene Climate Variability", "uid": "p0000155", "west": 161.0434}, {"awards": "0440636 Fahnestock, Mark; 0440670 Hulbe, Christina", "bounds_geometry": "POLYGON((-180 -70,-175 -70,-170 -70,-165 -70,-160 -70,-155 -70,-150 -70,-145 -70,-140 -70,-135 -70,-130 -70,-130 -71.6,-130 -73.2,-130 -74.8,-130 -76.4,-130 -78,-130 -79.6,-130 -81.2,-130 -82.8,-130 -84.4,-130 -86,-135 -86,-140 -86,-145 -86,-150 -86,-155 -86,-160 -86,-165 -86,-170 -86,-175 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -86,180 -84.4,180 -82.8,180 -81.2,180 -79.6,180 -78,180 -76.4,180 -74.8,180 -73.2,180 -71.6,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,180 -70,-180 -70))", "dataset_titles": "MOA-derived Structural Feature Map of the Ronne Ice Shelf; MOA-derived Structural Feature Map of the Ross Ice Shelf; Using Fracture Patterns and Ice Thickness to Study the History and Dynamics of Grounding Line Migration and Shutdown of Kamb and Whillans Ice Streams", "datasets": [{"dataset_uid": "600024", "doi": "", "keywords": null, "people": "Fahnestock, Mark", "repository": "USAP-DC", "science_program": null, "title": "Using Fracture Patterns and Ice Thickness to Study the History and Dynamics of Grounding Line Migration and Shutdown of Kamb and Whillans Ice Streams", "url": "https://www.usap-dc.org/view/dataset/600024"}, {"dataset_uid": "609497", "doi": "10.7265/N5PR7SXR", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; MOA; MODIS; Ronne Ice Shelf", "people": "Ledoux, Christine; Hulbe, Christina", "repository": "USAP-DC", "science_program": null, "title": "MOA-derived Structural Feature Map of the Ronne Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/609497"}, {"dataset_uid": "601432", "doi": "10.15784/601432", "keywords": "Antarctica", "people": "Forbes, Martin; Ledoux, Christine; Hulbe, Christina", "repository": "USAP-DC", "science_program": null, "title": "MOA-derived Structural Feature Map of the Ross Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601432"}], "date_created": "Thu, 25 Sep 2008 00:00:00 GMT", "description": "This award supports a three year project to develop the tools required to interpret complex patterns of flow features on the Ross Ice Shelf, which record the discharge history the ice streams flowing east off of the West Antarctic Ice Sheet. This work builds on previous research that used flow features visible in satellite image mosaics and numerical models of ice shelf flow to detect changes in grounding zone dynamics and redirection of ice stream outlets over hundreds of years. Recently observed changes on Whillans Ice Stream fit within this framework. The pattern of redirection is driven by the influence of rapid downstream thinning on the basal thermal gradient in the ice and associated \"sticky spot\" (ice rise) formation. In pursuing this work, the investigators recognized other records of discharge variation on the shelf that can be used to build a more complete history and understanding of ice-stream discharge variability. The intellectual merit of the proposed work lies in the fact that these records, including fracture patterns and spatial variation in ice thickness, when understood in the proper context, will yield quantitative information about the timing and dynamics of ice stream slowdowns, grounding line retreat, and the relative history of discharge between the ice streams. New tools will help further constrain this history. The laser altimeter on NASA\u0027s IceSAT has improved our knowledge of the surface elevation of Antarctic ice. IceSAT surface elevations provide a high-resolution map of ice-shelf thickness that, along with provenance maps from ice-shelf image mosaics, will be used to estimate the volumes of ice involved in past ice-stream discharge events (slowdowns, redirections, and so on). This project will develop new numerical models for fracture propagation; these will allow past variations in ice-shelf stress state to be investigated. Together, the dynamic and volume-flux histories will provide a powerful set of observations for understanding past variations in ice stream discharge and the underlying physical processes. The broader impacts of this project center on how it contributes to the ability to estimate West Antarctic contributions to global sea level rise and to answer outstanding questions about the causes of millennial and longer-scale evolution of ice streams. This work will provide a history of the most complex record of ice discharge known. In addition to the incorporation of this research into graduate student advising and normal teaching duties, the investigators are involved in other avenues of civic engagement and education. Outreach to high school students and the community at large is promoted on an annual basis by the investigators at both institutions. New outreach projects at Portland State University are developed with the assistance of researchers with expertise in student learning and achievement in science and mathematics. The collaborative research team includes two glaciologists with experience in the pairing of high resolution satellite imagery and a variety of ice-flow models and a geologist whose focus is the mechanics of rock deformation.", "east": -130.0, "geometry": "POINT(-155 -78)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e MODIS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e MODIS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; Fracture Patterns; Ross Ice Shelf; West Antarctic Ice Sheet; Not provided; Antarctica; TERRA; Ice Sheet; Ice Rise; LABORATORY; Ice-Stream Discharge; West Antarctica; Fracture Propagation; SATELLITES; Ice Stream Motion; Grounding Line; Ice Movement; Ice Stream; Whillans Ice Stream; Ice Stream Outlets; Basal Temperature Gradient; Numerical Model; Ice Thickness; Flow Features; Kamb Ice Stream; Antarctic Ice Sheet; Satellite Image Mosaics; Icesat; Grounding Line Migration; ICESAT", "locations": "Kamb Ice Stream; Whillans Ice Stream; Antarctica; Ross Ice Shelf; West Antarctic Ice Sheet; Antarctic Ice Sheet; West Antarctica", "north": -70.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Hulbe, Christina; Ledoux, Christine; Fahnestock, Mark", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e ICE, CLOUD AND LAND ELEVATION SATELLITE (ICESAT) \u003e ICESAT; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e TERRA", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Collaborative Research: Using Fracture Patterns and Ice Thickness to Study the History and Dynamics of Grounding Line Migration and Shutdown of Kamb and Whillans Ice Streams", "uid": "p0000096", "west": 180.0}, {"awards": "0124049 Berger, Glenn", "bounds_geometry": "POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 25 Aug 2008 00:00:00 GMT", "description": "0124049\u003cbr/\u003eBerger\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.", "east": 163.4, "geometry": "POINT(162.4 -77.6)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS", "is_usap_dc": false, "keywords": "Stratigraphy; Climate Variability; Shoreline Deposits; Dry Valleys; Antarctic Lake-level; Luminescence Geochronology; Grain Size; Paleoclimate; Antarctica; LABORATORY; Lake Cores", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Berger, Glenn; Hall, Brenda; Doran, Peter", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -77.7, "title": "Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change", "uid": "p0000219", "west": 161.4}, {"awards": "0701232 Martinson, Douglas", "bounds_geometry": "POLYGON((-72 -64,-71.2 -64,-70.4 -64,-69.6 -64,-68.8 -64,-68 -64,-67.2 -64,-66.4 -64,-65.6 -64,-64.8 -64,-64 -64,-64 -64.4,-64 -64.8,-64 -65.2,-64 -65.6,-64 -66,-64 -66.4,-64 -66.8,-64 -67.2,-64 -67.6,-64 -68,-64.8 -68,-65.6 -68,-66.4 -68,-67.2 -68,-68 -68,-68.8 -68,-69.6 -68,-70.4 -68,-71.2 -68,-72 -68,-72 -67.6,-72 -67.2,-72 -66.8,-72 -66.4,-72 -66,-72 -65.6,-72 -65.2,-72 -64.8,-72 -64.4,-72 -64))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 03 Jun 2008 00:00:00 GMT", "description": "The Antarctic Peninsula (AP) is characterized by (1) the most rapid recent regional (winter) warming (5.35 times global mean), (2) a loss of nearly all its perennial sea ice cover on its western margin, and (3) 87% of the glaciers in retreat, contributing to global sea level rise. An ability to understand this change depends upon researchers\u0027 ability to better understand the underlying sources of this change and their driving mechanisms. Despite intensive efforts, the western AP (WAP) is chronically under-sampled. Therefore developing a capability to maintain a sustained in situ presence is a high scientific priority. The current proposal addresses this critical need through 2 objectives: (1) establish the feasibility of a Slocum Webb ocean glider to enable real-time high resolution data-adaptive polar oceanographic research; (2) address a critical question involving the regional climate change by measuring the ocean heat budget within a grid containing 14 years of ship-based ocean snapshots. This will involve the launch of the glider during the PAL-LTER austral summer research cruise, where it will fly the full along-shore distance of the LTER sample grid to be recovered at the southern extreme when the ship arrives there later in the summer. The glider will provide nearly continuous ocean property (temperature, salinity and pressure) coverage over this distance.\u003cbr/\u003e\u003cbr/\u003eIntellectual merit. The proposed activity will involve state of the art sampling methodology that will revolutionize the ability to address climate change and other scientific issues requiring sampling densities that could not be achieved by research vessels. Specifically, the adaptive sampling capability of the glider will be used to alter its course allowing identification of routes by which the source waters of the ocean heat (and nutrients) enter the continental shelf region, while the near-continuous sampling will provide a diagnosis of how well standard shipborne stations close the heat budget. Resources are adequate for this study due to heavy leveraging by the availability of the Rutgers SLOCUM Web glider, glider control center and participation of the team of experts that flew the first such glider.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts. The proposed activity will advance discovery and understanding of the WAP responses to climate variability, to study the intricate feedback mechanisms associated with this variability and to better understand the chemical and physical processes associated with climate change. The data will be made available across the World Wide Web as it is collected, almost in real time, a potential bonanza for scientists during the upcoming International Polar Year, for classroom instruction and general outreach. Society will ultimately benefit from the improved knowledge of how climate change elsewhere in the world is impacting the unique ecosystem of the Antarctic, and driving glacial melt (sea level rise), among its other influences.", "east": -64.0, "geometry": "POINT(-68 -66)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e TEMPERATURE PROFILERS", "is_usap_dc": false, "keywords": "Pressure; Oceanography; AUVS; SLOCUM Web Glider; Salinity; Climate; Sampling", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Martinson, Douglas; Kerfoot, John", "platforms": "WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES \u003e SUBSURFACE \u003e AUVS", "repositories": null, "science_programs": null, "south": -68.0, "title": "Collaborative Research: Sloccum Glider in Western Antarctic Peninsula Continental Shelf Waters Pilot Study", "uid": "p0000734", "west": -72.0}, {"awards": "0440609 Price, P. Buford", "bounds_geometry": "POINT(-112.06556 -79.469444)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 03 Jun 2008 00:00:00 GMT", "description": "This award supports a project to use three downhole instruments - an optical logger; a\u003cbr/\u003eminiaturized biospectral logger at 420 nm (miniBSL-420); and an Acoustic TeleViewer (ATV) - to log a 350-m borehole at the WAIS Divide drill site. In addition, miniBSL-224 (at 224 nm) and miniBSL-420 will scan ice core sections at NICL to look for abrupt climate changes, volcanic ash, microbial concentrations, and correlations among them. Using the optical logger and ATV to log bubble number densities vs depth in a WAIS Divide borehole, we will detect annual layers, from which we can establish the age vs depth relation to the bottom of the borehole that will be available during the three-year grant period. With the same instruments we will search for long-period modulation of bubble and dust concentrations in order to provide definitive evidence for or against an effect of long-period variability of the sun or solar wind on climate. We will detect and accurately date ash layers in a WAIS Divide borehole. We will match them with ash layers that we previously detected in the Siple Dome borehole, and also match them with sulfate and ash layers found by others at Vostok, Dome Fuji, Dome C, and GISP2. The expected new data will allow us to extend our recent study which showed that the Antarctic record of volcanism correlates with abrupt climate change at a 95% to \u003e99.8% significance level and that the volcanic signatures at bipolar locations match at better than 3 sigma during the interval 2 to 45 kiloyears. The results to be obtained during this grant period will position us to extend an accurate age vs depth relation and volcano-climate correlations to earlier than 150 kiloyears ago in the future WAIS Divide borehole to be drilled to bedrock. Using the miniBSLs to identify biomolecules via their fluorescence, we will log a 350-m borehole at WAIS Divide, and we will scan selected lengths of ice core at NICL. Among the biomolecules the miniBSLs can identify will be chlorophyll, which will provide the first map of aerobic microbes in ice, and F420, which will provide the first map of methanogens in ice. We will collaborate with others in relating results from WAIS Divide and NICL ice cores to broader topics in climatology, volcanology, and microbial ecology. We will continue to give broad training to undergraduate and graduate students, to attract underrepresented minorities to science, engineering, and math, and to educate the press and college teachers. A deeper understanding of the causes of abrupt climate change, including a causal relationship with strong volcanic eruptions, can enable us to understand and mitigate adverse effects on climate.", "east": -112.06556, "geometry": "POINT(-112.06556 -79.469444)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUORESCENCE SPECTROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS", "is_usap_dc": false, "keywords": "Volcanic Ash; Dust Concentration; Antarctica; FIELD INVESTIGATION; Liquid Veins In Ice; Optical Logger; Borehole; Ash Layer; FIELD SURVEYS; Microbial Metabolism; Climate; Biospectral Logger; Not provided; Protein Fluorescence; Gas Artifacts; Aerosol Fluorescence; Volcanism; WAIS Divide; Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.469444, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bay, Ryan; Price, Buford", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repositories": null, "science_programs": null, "south": -79.469444, "title": "Climatology, Volcanism, and Microbial Life in Ice with Downhole Loggers", "uid": "p0000746", "west": -112.06556}, {"awards": "0537960 Beardsley, Robert", "bounds_geometry": "POLYGON((-110 -50,-104 -50,-98 -50,-92 -50,-86 -50,-80 -50,-74 -50,-68 -50,-62 -50,-56 -50,-50 -50,-50 -52.5,-50 -55,-50 -57.5,-50 -60,-50 -62.5,-50 -65,-50 -67.5,-50 -70,-50 -72.5,-50 -75,-56 -75,-62 -75,-68 -75,-74 -75,-80 -75,-86 -75,-92 -75,-98 -75,-104 -75,-110 -75,-110 -72.5,-110 -70,-110 -67.5,-110 -65,-110 -62.5,-110 -60,-110 -57.5,-110 -55,-110 -52.5,-110 -50))", "dataset_titles": "NODC Accession #0039274", "datasets": [{"dataset_uid": "001519", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "NODC Accession #0039274", "url": "http://www.nodc.noaa.gov/cgi-bin/search/prod/accessionsView.pl/details/0039274"}], "date_created": "Mon, 03 Mar 2008 00:00:00 GMT", "description": "Satellite-tracked drifters provide simple yet powerful tools to track the motion of near-surface water on time scales ranging from the tidal/inertial band to monthly and longer. The research described herein will deploy satellite-tracked surface drifters during the annual austral summer Palmer Long Term Ecological Research (LTER) cruises in January 2006 and 2007 in order to investigate the nearsurface Lagrangian currents over the western Antarctic Peninsula (wAP) shelf. This region is experiencing the highest surface air temperature increase (roughly +0.06 degrees C per year) in Antarctica, and LTER and other investigators have found that ecosystem responses to the rapid warming and sea ice decline are already apparent at all trophic levels from phytoplankton to penguins. Building a better understanding of the regional circulation and its variability seems an essential component to understand existing physical and biological processes and longer-term changes in this important and sensitive Antarctic ecosystem. These new Lagrangian measurements will complement those made during the 2001-2003 U.S. Southern Ocean (SO) GLOBEC program and provide the first detailed look at the near-surface flow in this important section of the wAP shelf. In particular, the combined 3-year LTER Lagrangian measurements should identify (a) the source region(s) of the buoyant coastal current discovered flowing southwest along the outer coast of Adelaide Island and into Marguerite Bay during SO GLOBEC and (b) if organized cross-shelf flows occur that help create a two gyre circulation over the shelf as suggested by Hofmann et al (1996) based on regional hydrography. The principal investigators will process and analyze the LTER 2005-2007 drifter data and collaborate with Palmer LTER investigators on the interpretation and integration of the Lagrangian data with their studies. The edited data, analysis results, and animations of the drifter data with surface weather data will be posted on the LTER website for use and viewing by scientists, students, and the public. Results will be presented at national meetings and published in referred journals.", "east": -50.0, "geometry": "POINT(-80 -62.5)", "instruments": null, "is_usap_dc": true, "keywords": null, "locations": null, "north": -50.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Beardsley, Robert; Limeburner, Richard", "platforms": null, "repo": "NCEI", "repositories": "NCEI", "science_programs": "LTER", "south": -75.0, "title": "Palmer LTER Lagrangian Current Measurements", "uid": "p0000232", "west": -110.0}, {"awards": "0337891 Brook, Edward J.", "bounds_geometry": "POINT(158 -77.666667)", "dataset_titles": "Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica; Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica", "datasets": [{"dataset_uid": "609315", "doi": "10.7265/N5542KJK", "keywords": "Antarctica; Atmosphere; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Ahn, Jinho; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609315"}, {"dataset_uid": "609314", "doi": "10.7265/N58W3B80", "keywords": "Antarctica; Atmosphere; Byrd Glacier; Byrd Ice Core; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Byrd Ice Core", "title": "Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609314"}], "date_created": "Mon, 05 Nov 2007 00:00:00 GMT", "description": "This award supports the development of a new laboratory capability in the U.S. to measure CO2 in ice cores and investigate millennial-scale changes in CO2 during the last glacial period using samples from the Byrd and Siple Dome ice cores. Both cores have precise relative chronologies based on correlation of methane and the isotopic composition of atmospheric oxygen with counterpart records from Greenland ice cores. The proposed work will therefore allow comparison of the timing of CO2 change, Antarctic temperature change, and Greenland temperature change on common time scales. Such comparisons are vital for evaluating models that explain changes in atmospheric CO2. The techniques being developed will also be available for future projects, specifically the proposed Inland WAIS ice core, for which a highly detailed CO2 record is a major objective, and studies greenhouse and other atmospheric gases and their isotopic composition for which dry extraction is necessary (stable isotopes in CO2, for example). There are many broad impacts of the proposed work. Ice core greenhouse gas records are central contributions of paleoclimatology to research and policy-making concerning global change. The proposed work will enhance those contributions by improving our understanding of the natural cycling of the most important greenhouse gas. It will contribute to the training of a postdoctoral researcher, who will be an integral part of an established research group and benefit from the diverse paleoclimate and geochemistry community at OSU. The PI teaches major and non-major undergraduate and graduate courses on climate and global change. The proposed work will enrich those courses and the courses will provide an opportunity for the postdoctoral researcher to participate in teaching by giving guest lectures. The PI also participates in a summer climate workshop for high school teachers at Washington State University and the proposed work will enrich that contribution. The extraction device that is built and the expertise gained in using it will be resources for the ice core community and available for future projects. Data will be made available through established national data center and the equipment designs will also be made available to other researchers.", "east": 158.0, "geometry": "POINT(158 -77.666667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Core; Climate Change; CO2; Atmospheric Chemistry; Atmospheric CO2; LABORATORY; Not provided; Ice Core Data; Climate; Ice Core Chemistry; Atmospheric Gases; Ice Core Gas Records; GROUND STATIONS; Climate Research", "locations": null, "north": -77.666667, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Ahn, Jinho; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.666667, "title": "Developing Dry Extraction of Ice Core Gases and Application to Millennial-Scale Variability in Atmospheric CO2", "uid": "p0000268", "west": 158.0}, {"awards": "0337948 Bromwich, David", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Access to data", "datasets": [{"dataset_uid": "001778", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Access to data", "url": "http://polarmet.mps.ohio-state.edu/PolarMet/ant_hindcast.html"}], "date_created": "Thu, 02 Aug 2007 00:00:00 GMT", "description": "This award supports a comprehensive investigation of the spatial and temporal characteristics of the surface mass balance of the Antarctic ice sheet and the governing mechanisms that affect it. A mesoscale atmospheric model, adapted for Antarctic conditions (Polar MM5), will be used in conjunction with the newly available reanalysis from the European Centre for Medium-Range Weather Forecasts (ECMWF) to resolve the surface mass balance of Antarctica at a time resolution of 3 hours and a spatial resolution of 60 km from 1957 to 2001. Polar MM5 will be upgraded to account for key processes in the simulation, including explicit consideration of blowing snow transport and sublimation as well as surface melting/runoff. The proposed 45-y hindcast of all Antarctic surface mass balance components with a limited area model has not previously been attempted and will provide a dataset of unprecedented scope to complement existing ice core measurements of recent climate, especially those collected by the International Transantarctic Scientific Expedition (ITASE). The trends and variability in space and time over 4.5 decades will be resolved and the impact of the dominant modes of atmospheric variability (Antarctic Oscillation, El Nino-Southern Oscillation, etc.) will be isolated. Hypotheses concerning the Antarctic surface mass balance response to climate change will be tested. The research will provide a sound basis for evaluating the impact of future climate change on Antarctic surface mass balance and its contribution to global sea level change as well as providing an important perspective for the interpretation of Antarctic ice core records. The broader impacts include the education of a Ph.D. student, the development of material for use in university classes, and construction of an interactive educational webpage on Antarctic surface mass balance.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e MMS", "is_usap_dc": false, "keywords": "El Nino-Southern Oscillation; ITASE; Atmospheric Model; Enso; Not provided; Antarctic Oscillation; Mesoscale; Antarctic; Polar Mm5; Climate", "locations": "Antarctic", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bromwich, David; Monaghan, Andrew", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website", "science_programs": null, "south": -90.0, "title": "A 45-Y Hindcast of Antarctic Surface Mass Balance Using Polar MM5", "uid": "p0000722", "west": -180.0}, {"awards": "0233303 Jacobs, Stanley", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Jul 2007 00:00:00 GMT", "description": "Major portions of the Antarctic Ice Sheet float in the surrounding ocean, at the physical and intellectual boundaries of oceanography and glaciology. These ice shelves lose mass continuously by melting into the sea, and periodically by the calving of icebergs. Those losses are compensated by the outflow of grounded ice, and by surface accumulation and basal freezing. Ice shelf sources and sinks vary on several time scales, but their wastage terms are not yet well known. Reports of substantial ice shelf retreat, regional ocean freshening and increased ice velocity and thinning are of particular concern at a time of warming ocean temperatures in waters that have access to deep glacier grounding lines.\u003cbr/\u003eThis award supports a study of the attrition of Antarctic ice shelves, using recent ocean geochemical measurements and drawing on numerical modeling and remote sensing resources. In cooperation with associates at Columbia University and the British Antarctic Survey, measurements of chlorofluorocarbon, helium, neon and oxygen isotopes will be used to infer basal melting beneath the Ross Ice Shelf, and a combination of oceanographic and altimeter data will be used to investigate the mass balance of George VI Ice Shelf. Ocean and remote sensing observations will also be used to help refine numerical models of ice cavity circulations. The objectives are to reduce uncertainties between different estimates of basal melting and freezing, evaluate regional variability, and provide an update of an earlier assessment of circumpolar net melting.\u003cbr/\u003eA better knowledge of ice shelf attrition is essential to an improved understanding of ice shelf response to climate change. Large ice shelf calving events can alter the ocean circulation and sea ice formation, and can lead to logistics problems such as those recently experienced in the Ross Sea. Broader impacts include the role of ice shelf meltwater in freshening and stabilizing the upper ocean, and in the formation of Antarctic Bottom Water, which can be traced far into the North Atlantic. To the extent that ice shelf attrition influences the flow of grounded ice, this work also has implications for ice sheet stability and sea level rise.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Ice Sheet; Basal Melting; Ice Shelf Meltwater; Not provided; Oceanography; Ice Velocity; Glaciology; Sea Level Rise; Ice Sheet Stability; Mass; Ross Ice Sheet; Numerical Model; Basal Freezing; Ice Cavity Circulations; George VI Ice Shelf; Outflow", "locations": "Ross Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Jacobs, Stanley", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Melting and Calving of Antarctic Ice Shelves", "uid": "p0000730", "west": null}, {"awards": "0125754 Hulbe, Christina", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Thu, 07 Jun 2007 00:00:00 GMT", "description": "This award supports a project to develop computational models to simulate ice-shelf rift propagation using a combination of well-established ice-shelf creep-flow models and new crevasse models, based on linear elastic fracture mechanics (LEFM). The overall objective of the proposed work is to simulate rift propagation and eventual large iceberg calving,and place those processes within a larger ice sheet and climate context. The work will proceed in stages, first developing models of single-and multiple-crevasse propagation; then using those models to evaluate propagation sensitivity to various environmental conditions; and third developing models that incorporate both crevasse propagation and advection within an ice- shelf system. Model development will be guided by and evaluated according to satellite observations of rift propagation in several characteristic locations on Antarctic ice shelves. New numerical models of fracture in ice will have applications to many problems in glaciology. The research proposed here is directed toward large rift formation in ice shelves and subsequent iceberg calving. It is motivated by the need to understand observed changes in modern ice shelves,and their connection to climate. Where it has been sampled, the sedimentary record of the Weddell Sea sector implies Peninsular ice shelf variability on millennial time scales. The ability to simulate iceberg calving in a credible way will improve our ability to reproduce such events and place the complete cycle of ice shelf advance and retreat in an ice-dynamics context. That will, in turn, enable us to place ice-shelf cycles within the climate cycles that ultimately drive ice-sheet mass balance.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hulbe, Christina", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Ice-Shelf Rift Propagation: Computational Simulation Using a Fracture Fracture Mechanics Approach", "uid": "p0000270", "west": null}, {"awards": "0229573 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Antarctic Mean Annual Temperature Map", "datasets": [{"dataset_uid": "609318", "doi": "10.7265/N51C1TTV", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Temperature", "people": "Dixon, Daniel A.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Mean Annual Temperature Map", "url": "https://www.usap-dc.org/view/dataset/609318"}], "date_created": "Wed, 04 Apr 2007 00:00:00 GMT", "description": "This award supports a science management office for a pilot ice-core drilling and analysis program to test the feasibility of obtaining well-dated, high-resolution isotope and chemistry records from East Antarctica. Shallow ice cores will be obtained from two locations: 1) ~100 km from South Pole towards the Pole of Inaccessibility, as an extension of the Byrd Station-to-South Pole ITASE traverse [International Trans Antarctic Scientific Expedition]; 2) at Taylor Dome, near the original deep coring site, and (3) possibly at AGO 3 and AGO 4 as part of a logistics traverse to these sites. All of the cores collected will be sampled at very high resolution (~1/2 cm) and analyzed for major ions. Results from this calibration work, along with those from another project that is analyzing stable isotopes will be used to help plan a program of larger scope, with the objective of mapping the spatial expression of climate variability in East Antarctica. Funds are also provided to organize a community workshop for coordination of the second phase of US ITASE and for one workshop per year for two years dedicated to writing and preparation of scientific papers from phase one of US ITASE. In addition, route selection activities for the follow-on traverse activities in East Antarctica will be conducted using satellite image mapping. A summary document will be produced and made available to the community to help with planning of related field programs (e.g. deep ice radar, firn radar profiling, atmospheric chemistry, ice coring, snow surface properties for satellite observations, ice surface elevation and mass balance).", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOCOUPLES \u003e THERMOCOUPLES; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOMETERS \u003e THERMOMETERS", "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; West Antarctica; FIELD INVESTIGATION; West Antarctic Ice Sheet; Antarctic; Temperature; East Antarctic Plateau; FIELD SURVEYS; Antarctica; Not provided", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet; East Antarctic Plateau", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Dixon, Daniel A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "A Science Management Office for the U. S. Component of the International Trans Antarctic Expedition (US ITASE SMO)A Collaborative Pgrm of Research from S. Pole to N. Victoria Land", "uid": "p0000199", "west": null}, {"awards": "0229292 Cressie, Noel", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 28 Feb 2007 00:00:00 GMT", "description": "Ice streams are believed to play a major role in determining the response of their parent ice sheet to climate change, and in determining global sea level by serving as regulators on the fresh water stored in the ice sheets. Ice streams are characterized by rapid, laterally confined flow which makes them uniquely identifiable within the body of the more slowly and more homogeneously flowing ice sheet. But while these characteristics enable the identification of ice streams, the processes which control ice-stream motion and evolution, and differences among ice streams in the polar regions, are only partially understood. Understanding the relative importance of lateral and basal drags, as well as the role of gradients in longitudinal stress, is essential for developing models for future evolution of the polar ice\u003cbr/\u003esheets. In this project, physical statistical models will be used to explore the processes that control ice-stream flow, and to compare these processes between seemingly different ice-stream systems. In particular, Whillans Ice Stream draining into the Ross Ice Shelf, will be compared with Recovery and RAMP glaciers draining into the Ronne-Filchner Ice Shelf, and the Northeast Ice Stream in Greenland. Geophysical models lie at the core of the approach, but are embellished by modeling various components of variability statistically. One important component comes from the uncertainty in observations on basal elevation, surface elevation, and surface velocity. In this project new observational data collected using remote-sensing techniques will be used. The various components, some of which are spatial, are combined hierarchically using Bayesian statistical methodology. All these components will be combined mathematically into a physical statistical model that yields the posterior distribution for basal, longitudinal, and lateral stress fields, and velocity fields, conditional on the data. Inference based on this distribution will be carried out via Markov chain Monte Carlo techniques, to obtain estimates of these unknown fields along with uncertainty measures associated with them.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Surface Elevation; Stress Field; Basal Elevation; DHC-6", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Cressie, Noel; Jezek, Kenneth; Berliner, L.", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e DHC-6", "repositories": null, "science_programs": null, "south": null, "title": "Dynamics of Ice Streams: A Physical Statistical Approach", "uid": "p0000711", "west": null}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}, {"awards": "0230378 Kanagaratnam, Pannirselvam", "bounds_geometry": "POLYGON((-112.224 -79.3385,-112.1245 -79.3385,-112.025 -79.3385,-111.9255 -79.3385,-111.826 -79.3385,-111.7265 -79.3385,-111.627 -79.3385,-111.5275 -79.3385,-111.428 -79.3385,-111.3285 -79.3385,-111.229 -79.3385,-111.229 -79.35475,-111.229 -79.371,-111.229 -79.38725,-111.229 -79.4035,-111.229 -79.41975,-111.229 -79.436,-111.229 -79.45225,-111.229 -79.4685,-111.229 -79.48475,-111.229 -79.501,-111.3285 -79.501,-111.428 -79.501,-111.5275 -79.501,-111.627 -79.501,-111.7265 -79.501,-111.826 -79.501,-111.9255 -79.501,-112.025 -79.501,-112.1245 -79.501,-112.224 -79.501,-112.224 -79.48475,-112.224 -79.4685,-112.224 -79.45225,-112.224 -79.436,-112.224 -79.41975,-112.224 -79.4035,-112.224 -79.38725,-112.224 -79.371,-112.224 -79.35475,-112.224 -79.3385))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 18 Oct 2006 00:00:00 GMT", "description": "This award supports a project to build and test a 12-18 GHz radar system with a plane wave antenna. This is a wideband radar operating over a frequency range of 12 to 18 GHz to detect near-surface internal firn layers of the ice sheet with better than 10 cm resolution to a depth of approximately 7 m. These measurements will allow determination of spatially continuous snow accumulation rate in the firn, which would be useful along a traverse and is of critical importance to the validation of CryoSat and ICESAT satellite missions aimed at assessing the current state of mass balance of the polar ice sheets. The antenna system planned for the radar is relatively compact, and will be located on the sledge carrying the radar systems. The broad scientific focus of this project will be to investigate important glacial processes relevant to ice sheet mass balance. The new radar will allow the characterization (with high depth resolution) of the spatial variability of snow accumulation rate along a traverse route for interpreting data from CryoSat and ICESAT missions. As part of this project, we will institute a strong outreach program involving K-12 education and a minority institution of higher education. We currently work closely with the Advanced Learning Technology Program (ALTec) at the University of Kansas to develop interactive, resource-based lessons for use on-line by students of all grade levels, and we will develop new resources related to this project. We currently have an active research and education collaboration with faculty and undergraduate students at neighboring Haskell Indian Nations University, in Lawrence, Kansas, and we will expand our collaboration to include this project.", "east": -111.229, "geometry": "POINT(-111.7265 -79.41975)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": false, "keywords": "Firn; Cryosat; Plane Wave Antenna; Glacial Processes; GROUND-BASED OBSERVATIONS; Not provided; Icesat; FIELD INVESTIGATION; Radar; LABORATORY; Snow Accumulation; Mass Balance; FIELD SURVEYS", "locations": null, "north": -79.3385, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kanagaratnam, Pannirselvam; Braaten, David; Bauer, Rob", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.501, "title": "High Resolution Ice Thickness and Plane Wave Mapping of Near-Surface Layers", "uid": "p0000731", "west": -112.224}, {"awards": "0338359 Saltzman, Eric", "bounds_geometry": "POINT(-148.81 -81.65)", "dataset_titles": "Analysis of Siple Dome Ice Core: Carbonyl Sulfide (COS), Methyl Chloride (CH3Cl), and Methyl Bromide (CH3Br); Antarctic Ice Cores: Methyl Chloride and Methyl Bromide; Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core; Methane and Carbonyl Sulfide Analysis of Siple Dome Ice Core Subsamples", "datasets": [{"dataset_uid": "609313", "doi": "10.7265/N5DN430Q", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; ITASE; Paleoclimate; Siple Dome Ice Core; South Pole; SPRESSO; SPRESSO Ice Core", "people": "Saltzman, Eric; Williams, Margaret; Tatum, Cheryl; Aydin, Murat", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Ice Cores: Methyl Chloride and Methyl Bromide", "url": "https://www.usap-dc.org/view/dataset/609313"}, {"dataset_uid": "609279", "doi": "10.7265/N53B5X3G", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Analysis of Siple Dome Ice Core: Carbonyl Sulfide (COS), Methyl Chloride (CH3Cl), and Methyl Bromide (CH3Br)", "url": "https://www.usap-dc.org/view/dataset/609279"}, {"dataset_uid": "609131", "doi": "10.7265/N5P848VP", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Methane and Carbonyl Sulfide Analysis of Siple Dome Ice Core Subsamples", "url": "https://www.usap-dc.org/view/dataset/609131"}, {"dataset_uid": "601357", "doi": "10.15784/601357", "keywords": "Antarctica; Atmospheric Gases; Gas Measurement; Ice Core; Ice Core Gas Records; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core", "url": "https://www.usap-dc.org/view/dataset/601357"}], "date_created": "Wed, 16 Nov 2005 00:00:00 GMT", "description": "This award supports the analysis, in Antarctic ice cores, of the ozone depleting substances methyl bromide (CH3Br) and methyl chloride (CH3Cl), and the sulfur-containing gas, carbonyl sulfide (OCS). The broad scientific goal is to assess the level and variability of these gases in the preindustrial atmosphere. This information will allow testing of current models for sources and sinks of these gases from the atmosphere, and to indirectly assess the impact of anthropogenic activities on their biogeochemical cycles. Longer-term records will shed light on the climatic sensitivity of the atmospheric burden of these gases, and ultimately on the biogeochemical processes controlling them. These gases are present in ice at parts per trillion levels, and the current database consists entirely of a small number of measurements made in from a shallow ice core from Siple Dome, Antarctica. This project will involve studies of ice core samples from three Antarctic sites: Siple Station, Siple Dome, and South Pole. The sampling strategy is designed to accomplish several objectives: 1) to verify the atmospheric mixing ratios previously observed in shallow Siple Dome ice for OCS, CH3Br, and CH3Cl at sites with very different accumulation rates and surface temperatures; 2) to obtain a well-dated, high resolution record from a high accumulation rate site (Siple Station), that can provide overlap in mean gas age with Antarctic firn air samples; 3) explore Holocene variability in trace gas mixing ratios; and 4) to make the first measurements of these trace gases in Antarctic glacial ice. In terms of broader impact on society, this research will help to provide a stronger scientific basis for policy decisions regulating the production and use of ozone-depleting and climate-active gases. Specifically, the methyl bromide results will contribute to the current debate on the impact of recent regulation (via the Montreal Protocol and its Amendments) on atmospheric levels. Determination of pre-industrial atmospheric variability of ozone-depleting substances will help place more realistic constraints on scenarios used for future projections of stratospheric ozone and its climatic impacts. This research will involve the participation of both graduate and undergraduate students.", "east": -148.81, "geometry": "POINT(-148.81 -81.65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core Gas Records; Carbonyl Sulfide; Siple Coast; Chloride; Trapped Gases; Snow; Ice Core Chemistry; Chromatography; Siple; GROUND STATIONS; Atmospheric Gases; Ozone Depletion; AWS Siple; Ice Sheet; Ice Core Data; Antarctica; Glaciology; West Antarctica; Atmospheric Chemistry; Ice Core; Stratigraphy; LABORATORY; Methane; Mass Spectrometer; GROUND-BASED OBSERVATIONS; WAISCORES; Msa; Mass Spectrometry; Not provided; Siple Dome; Gas Measurement", "locations": "Antarctica; Siple Coast; Siple Dome; West Antarctica; Siple", "north": -81.65, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Saltzman, Eric; Aydin, Murat; Williams, Margaret; Tatum, Cheryl", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.65, "title": "Methyl chloride and methyl bromide in Antarctic ice cores", "uid": "p0000032", "west": -148.81}, {"awards": "0088054 Goldstein, Steven", "bounds_geometry": "POLYGON((-180 -39.57,-144 -39.57,-108 -39.57,-72 -39.57,-36 -39.57,0 -39.57,36 -39.57,72 -39.57,108 -39.57,144 -39.57,180 -39.57,180 -42.967,180 -46.364,180 -49.761,180 -53.158,180 -56.555,180 -59.952,180 -63.349,180 -66.746,180 -70.143,180 -73.54,144 -73.54,108 -73.54,72 -73.54,36 -73.54,0 -73.54,-36 -73.54,-72 -73.54,-108 -73.54,-144 -73.54,-180 -73.54,-180 -70.143,-180 -66.746,-180 -63.349,-180 -59.952,-180 -56.555,-180 -53.158,-180 -49.761,-180 -46.364,-180 -42.967,-180 -39.57))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 26 Apr 2005 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the sediment core from the Southern Ocean for paleoenvironmental research. The polar regions are susceptible to the largest changes in climate and are among the least accessible places on Earth. Current concern about the instability of the West Antarctic Ice Sheet has heightened awareness of the vulnerability of polar regions. This proposal seeks to gain a basic understanding of the isotopic characteristics of terrigenous sediment sources derived from Antarctica in the Holocene and Last Glacial Maximum, and their dispersal into the Southern Ocean. Terrigenous clastic sediments are brought to the ocean from continental sources via rivers, ice and wind, and distributed within the ocean by surface and deep currents. At present there are virtually no isotopic data on circumpolar detritus, save a few strontium (Sr) isotopic ratios in the Atlantic sector. This project will fill part of this gap. From the large range in geological ages of crustal provinces of Antarctica, we would predict that there are large isotopic differences in detritus around the continent. The main objectives are to (1) characterize the strontium-neodymium-lead-argon (Sr-Nd-Pb-Ar) isotope compositions of sediment sources derived from Antarctica, (2) to identify the composition and source ages of major ice rafted detritus (IRD) contributions by analyzing individual grains of hornblende and feldspar in conjunction with bulk isotopic analysis, and (3) track sediment dispersal into the Antarctic Circumpolar Current (ACC) during the Holocene and Last Glacial Maximum.\u003cbr/\u003e\u003cbr/\u003eBecause of the paucity of circumpolar data, this research necessarily has a large exploratory component. Consequently, it will provide a basic database for future studies. Nevertheless there are important hypothesis-driven questions that will be addressed in this primary pass. Can lessons learned in North Atlantic IRD studies be applied toward understanding the history of Antarctic ice sheets? Can the large geological variability around the Antarctic margin be treated as a series of natural tracer injections into the ACC, and thus characterize its trajectory, speed, and interaction with other current systems today and in the past? The proposed study is motivated by an exciting set of results from the South Atlantic, showing that detrital Sr isotope ratios are a sensitive current tracer in that region. This research should serve a basic need across many Earth Science disciplines if the use of long-lived radiogenic isotopes (Sr-Nd-Pb-Ar) as tracers of marine sediment sources is successful in elucidating processes related to changing climatic conditions. The results of this study will fill a basic gap in our knowledge of an important region of the Earth. At the same time, it will provide an essential basis for attempting reconstruction of the ACC during the LGM, as well as for future studies of Antarctic geology, ice sheet history, and the Southern Ocean circulation.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -39.57, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Roy, Martin; Hemming, Sidney R.; Goldstein, Steven L.; Van De Flierdt, Christina-Maria", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -73.54, "title": "Establishing the Pattern of Holocene-LGM Changes in Sediment Contributions from Antarctica to the Southern Ocean", "uid": "p0000724", "west": -180.0}, {"awards": "9714687 Brook, Edward J.", "bounds_geometry": null, "dataset_titles": "Byrd Ice Core Microparticle and Chemistry Data", "datasets": [{"dataset_uid": "609247", "doi": "", "keywords": "Antarctica; Byrd; Byrd Ice Core; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate", "people": "Blunier, Thomas; Brook, Edward J.; Thompson, Lonnie G.; Fluckiger, Jacqueline", "repository": "USAP-DC", "science_program": "Byrd Ice Core", "title": "Byrd Ice Core Microparticle and Chemistry Data", "url": "https://www.usap-dc.org/view/dataset/609247"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "This award is for support for a program to make high resolution studies of variations in the concentration of methane, the oxygenisotope composition of paleoatmospheric oxygen, and the total gas content of deep Antarctic ice cores. Studies of the concentration and isotopic composition of air in the firn of the Antarctic ice sheet will also be continued. One objective of this work is to use the methane concentration and oxygen-isotope composition of oxygen of air in ice as time-stratigraphic markers for the precise intercorrelation of Greenland and Antarctic ice cores as well as the correlation of ice cores to other climatic records. A second objective is to use variations in the concentration and interhemispheric gradient of methane measured in Greenland and Antarctic ice cores to deduce changes in continental climates and biogeochemistry on which the atmospheric methane distribution depends. A third objective is to use data on the variability of total gas content in the Siple Dome ice core to reconstruct aspects of the glacial history of West Antarctica during the last glacial maximum. The fourth objective is to participate in collaborative studies of firn air chemistry at Vostok, Siple Dome, and South Pole which will yield much new information about gas trapping in ice as well as the concentration history and isotopic composition of greenhouse gases, oxygen, trace biogenic gases and trace anthropogenic gases during the last 100 years.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "GROUND STATIONS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Blunier, Thomas; Fluckiger, Jacqueline; Thompson, Lonnie G.; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Studies of Trapped Gases in Firn and Ice from Antarctic Deep Ice Cores", "uid": "p0000168", "west": null}, {"awards": "9316564 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis; Siple Dome Ice Core Chemistry and Ion Data", "datasets": [{"dataset_uid": "609266", "doi": "10.7265/N5M906KG", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; Snow Pit", "people": "Whitlow, Sallie; Twickler, Mark; Meeker, Loren D.; Mayewski, Paul A.; Kreutz, Karl", "repository": "USAP-DC", "science_program": null, "title": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis", "url": "https://www.usap-dc.org/view/dataset/609266"}, {"dataset_uid": "609251", "doi": "", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Brook, Edward J.; Blunier, Thomas; Severinghaus, Jeffrey P.; Kreutz, Karl; Mayewski, Paul A.; Dunbar, Nelia", "repository": "NCEI", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Ice Core Chemistry and Ion Data", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/2461"}], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of \u003e 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require \u003c 7% by volume of each core, leaving \u003e 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Magnesium; GROUND STATIONS; Nitrate; Methane Sulfonic Acid; Sodium; Ice Core Chemistry; Ammonium (NH4); Sulfate; Ice Core; Chloride; Potassium (k); Calcium (ca)", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Twickler, Mark; Whitlow, Sallie; Blunier, Thomas; Dunbar, Nelia; Brook, Edward J.; Mayewski, Paul A.; Meeker, Loren D.; Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "NCEI; USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability", "uid": "p0000145", "west": null}, {"awards": "9615333 Saltzman, Eric", "bounds_geometry": "POINT(-148.8 -81.7)", "dataset_titles": "Biogenic Sulfur in the Siple Dome Ice Core", "datasets": [{"dataset_uid": "609201", "doi": "10.7265/N5S180F1", "keywords": "Antarctica; Biota; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Saltzman, Eric; Finley, Brandon; Dioumaeva, Irina", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Biogenic Sulfur in the Siple Dome Ice Core", "url": "https://www.usap-dc.org/view/dataset/609201"}], "date_created": "Tue, 09 Mar 2004 00:00:00 GMT", "description": "This award is for support for four years of funding for a program of biogenic sulfur measurements on the Siple Dome ice core. Biogenic sulfur is a major aerosol-forming constituent of the atmosphere and has potentially important links to the earth\u0027s radiation budget. Previous work on the Vostok ice core has demonstrated a remarkable climate-related variability in biogenic sulfur, suggesting that the sulfur cycle may act to stabilize climate (keep the glacial atmosphere cool and the interglacial atmosphere warm) in the Southern Hemisphere. In this study, methane-sulfonate (MSA) will be measured on the Siple Dome ice core as part of the West Antarctic ice sheet program (WAIS). Siple Dome is located in a region which is strongly impacted by the incursion of marine air onto the Antarctic plateau. Because of its proximity to the coast and meteorological setting, it is expected that variability in high-latitude marine biogenic sulfur emissions should dominate the MSA record at this site. In addition to the deep ice core record, samples from shallow cores will also be analyzed to provide information about regional variability and decadal-to-centennial scale variability in the deposition of sulfur-containing aerosols from high latitude source regions over the past 200 years.", "east": -148.8, "geometry": "POINT(-148.8 -81.7)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Siple Dome; GROUND-BASED OBSERVATIONS; Biogenic Sulfur; FIELD INVESTIGATION; Not provided; LABORATORY; Methane Sulfonate", "locations": "Siple Dome", "north": -81.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Saltzman, Eric; Dioumaeva, Irina; Finley, Brandon", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.7, "title": "Biogenic Sulfur in the Siple Dome Ice Core", "uid": "p0000251", "west": -148.8}, {"awards": "9526420 Taylor, Kendrick", "bounds_geometry": null, "dataset_titles": "Siple Dome Cores Electrical Measurement Data", "datasets": [{"dataset_uid": "609133", "doi": "10.7265/N5DR2SDN", "keywords": "Antarctica; Electrical Conductivity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Taylor, Kendrick C.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Cores Electrical Measurement Data", "url": "https://www.usap-dc.org/view/dataset/609133"}], "date_created": "Thu, 08 May 2003 00:00:00 GMT", "description": "This award is for support for the measurement of electrical and optical properties of the Siple Dome ice core. The electrical methods can be used to determine the concentration of the hydrogen ions and the concentration of a weighted sum of all ions. The electrical measurements can resolve features as small as 1 cm. The albedo of the core is also measured with a laser system that can resolve features as small as 0.5 cm. The high spatial resolution of these methods makes them ideal for resolving narrow features in the core, which can be missed in larger composite samples. The measurements will be particularly useful for assisting to date the core and to identify short duration features in the record, such as volcanic eruptions. These measurements will also provide useful information for assessing the temporal variability of Holocene accumulation rate and atmospheric circulation.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Densification; Siple Dome; Glaciology; Snow; Thermometry; WAISCORES; Electrical; Isotope; GROUND STATIONS; GROUND-BASED OBSERVATIONS; Not provided; Ice Sheet; Siple Coast; Ice Core; Siple; Antarctica", "locations": "Antarctica; Siple; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Taylor, Kendrick C.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Electrical and Optical Measurements on the Siple Dome Ice Core", "uid": "p0000163", "west": null}, {"awards": "9526449 Mayewski, Paul", "bounds_geometry": null, "dataset_titles": "WAISCORES Snow Pit Chemistry, Antarctica", "datasets": [{"dataset_uid": "609420", "doi": "10.7265/N5SQ8XBR", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; Snow Pit; WAIS; WAISCORES", "people": "Kreutz, Karl; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": null, "title": "WAISCORES Snow Pit Chemistry, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609420"}], "date_created": "Thu, 11 Jul 2002 00:00:00 GMT", "description": "This award is for support for a program of glaciochemical analyses of shallow and deep ice cores from Siple Dome, West Antarctica. Measurements that have been proposed include chloride, nitrate, sulfate, calcium, magnesium, sodium, potassium, ammonium and methansulfonic acid. These measurements will provide information about past volcanic events, biomass source strength, sea ice fluctuations, atmospheric circulation, changes in ice-free areas and the environmental response to Earth orbit insolation changes and solar variability. The glaciochemical records from the Siple Dome core will be developed at a resolution sufficient to compare with the Summit, Greenland record, thus allowing a bipolar comparison of climate change event timing and magnitude. As part of this award, an international workshop will be held during the first year to formulate a science plan for the International Transantarctic Scientific Expedition (ITASE), a program of regional surveys documenting the spatial distribution of properties measured in ice cores .", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Ion Chemistry; Antarctic; Snow Chemistry; Stable Isotopes; Snow Density; Siple Dome; GROUND-BASED OBSERVATIONS", "locations": "Antarctic; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kreutz, Karl; Mayewski, Paul A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Siple Dome Deep Ice Core Glaciochemistry and Regional Survey - A Contribution to the WAIS Initiative", "uid": "p0000012", "west": null}, {"awards": "9530379 Anderson, Robert", "bounds_geometry": "POLYGON((-180 -54,-179 -54,-178 -54,-177 -54,-176 -54,-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-170 -55.2,-170 -56.4,-170 -57.6,-170 -58.8,-170 -60,-170 -61.2,-170 -62.4,-170 -63.6,-170 -64.8,-170 -66,-171 -66,-172 -66,-173 -66,-174 -66,-175 -66,-176 -66,-177 -66,-178 -66,-179 -66,180 -66,145 -66,110 -66,75 -66,40 -66,5 -66,-30 -66,-65 -66,-100 -66,-135 -66,-170 -66,-170 -64.8,-170 -63.6,-170 -62.4,-170 -61.2,-170 -60,-170 -58.8,-170 -57.6,-170 -56.4,-170 -55.2,-170 -54,-135 -54,-100 -54,-65 -54,-30 -54,5 -54,40 -54,75 -54,110 -54,145 -54,-180 -54))", "dataset_titles": "Data sets for RVIB Nathaniel B Palmer February-April, 1998, cruise; U.S. JGOFS Southern Ocean (AESOPS) Data", "datasets": [{"dataset_uid": "002116", "doi": "", "keywords": null, "people": null, "repository": "JGOF", "science_program": null, "title": "Data sets for RVIB Nathaniel B Palmer February-April, 1998, cruise", "url": "http://usjgofs.whoi.edu/jg/dir/jgofs/southern/nbp98_2/"}, {"dataset_uid": "002115", "doi": "", "keywords": null, "people": null, "repository": "JGOF", "science_program": null, "title": "U.S. JGOFS Southern Ocean (AESOPS) Data", "url": "http://usjgofs.whoi.edu/southernobjects.html"}, {"dataset_uid": "000249", "doi": "", "keywords": null, "people": null, "repository": "JGOF", "science_program": null, "title": "U.S. JGOFS Southern Ocean (AESOPS) Data", "url": "http://usjgofs.whoi.edu/southernobjects.html"}], "date_created": "Thu, 01 Jan 1970 00:00:00 GMT", "description": "9530379 Anderson This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three- year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component is a study of how naturally radioactive material in the ocean sediment may be used to reconstruct the flux of biogenic material through the water column to the sediment, and by inference, the productivity of the surface layers. There is evidence that the current surface conditions of high nutrient levels, but low chlorophyll levels do not extend back into colder climatic epochs, and that an examination of radionuclides may allow the reconstruction of rates of paleoproductivity. Two aspects of the biogeochemical cycling and physical transport of radionuclide tracers in the modern ocean will be investigated. In the first part, the concentration of a series of natural radionuclide tracers (thorium-230, protactinium-231, and Beryllium-10) in the Southern Ocean will be measured for their scavenging behavior both in the water column and in particulate material collected by sediment traps. The goal is to test the proposed use of radionuclide ratios as proxy variables for the export flux. In the second part, the concentration values will be introduced into an ocean general circulat ion model to evaluate the transport of radionuclides by the ocean circulation on scales that are larger than the spatial gradients in particle flux. These combined efforts will better define our ability to use radionuclide ratios to evaluate past changes in ocean productivity, and improve our understanding of the response of ocean productivity to climate variability. ***", "east": -170.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Beryllium; Calcium Carbonate; Thorium; Radionulides; Radiocarbon; Organic Carbon; Pa; Protactinium; Uranium; Opal; Th; Be; NBP9802; U; Not provided", "locations": null, "north": -54.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Anderson, Robert", "platforms": "Not provided", "repo": "JGOF", "repositories": "JGOF", "science_programs": null, "south": -66.0, "title": "Proxies of Past Changes in Southern Ocean Productivity: Modeling and Experimental Development", "uid": "p0000713", "west": -170.0}]
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Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. Since its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public's fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth's last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.
The West Antarctic Peninsula (WAP) is experiencing significant environmental changes, including warming temperatures, reduced sea ice, and glacier retreat. These changes could impact marine ecosystems and biological and chemical processes, particularly the biological pump, which is the process by which carbon is transported from the ocean surface to the deep sea, playing a crucial role in regulating atmospheric carbon dioxide levels. This project aims to understand how climate change affects the biological pump in the WAP region. Using a combination of advanced modeling techniques and data from long-term research programs, the project will investigate the processes governing the biological pump and its climate feedback. The findings will provide insights into the future dynamics of the WAP region and contribute to our understanding of climate change impacts on polar marine ecosystems. This research is important as it will enhance knowledge of how polar regions respond to climate change, which is vital for predicting global climate patterns and informing conservation efforts. Furthermore, the project supports the development of early-career researchers and promotes diversity in science through collaborations with educational programs and outreach to underrepresented communities. This project focuses on the WAP, a region undergoing rapid environmental changes. The goal is to investigate and quantify the factors controlling the biological pump and its feedback to climate change and variability. A novel hybrid modeling framework will be developed, integrating observational data from the Palmer Long-Term Ecological Research program and the Rothera Oceanographic and Biological Time-Series into a sophisticated one-dimensional mechanistic biogeochemical model. This framework will utilize Artificial Intelligence and Machine Learning techniques for data assimilation and parameter optimization. By incorporating complementary datasets and optimizing model parameters, the project aims to reduce uncertainties in modeling biological pump processes. The study will also use climate scenarios from the Coupled Model Intercomparison Project Phase 6 to assess the impacts of future climate conditions on the biological pump. Additionally, the project will examine the role of vertical mixing of dissolved organic matter in total export production, providing a comprehensive understanding of the WAP carbon cycle. The outcomes will improve temporal resolution and data assimilation, advancing the mechanistic understanding of the interplay between ocean dynamics and biogeochemical processes in the changing polar environment. The project will also leverage unique datasets and make the model framework and source codes publicly available, facilitating collaboration and benefiting the broader scientific community. Outreach efforts include engaging with educational programs and promoting diversity in Polar Science through collaborations with institutions serving underrepresented groups. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Marine ice sheets are low-pass filters of climate variability that take centuries to adjust to interior and near-terminus changes in mass balance. Constraining these century-scale changes from satellite observations that span only the last 40 years is challenging. Here, we take a different approach of carefully synthesizing different data sets to infer changes in the configurations of van der Veen and Mercer Ice Streams on the Siple Coast over the past 3000 years from englacial features encoded in ice-penetrating radar data. Englacial radar data from Conway Ridge reveal smooth, surface conformal layers overlying disrupted stratigraphy that suggest the van der Veen Ice Stream was 40 km wider over 3000 years ago. Englacial layer dating indicates that the ice stream narrowed to its present configuration between $\sim3000$ and $\sim1000$ years ago. Similarly disrupted stratigraphy and buried crevasses suggest that ice flowing from Mercer to Whillans Ice Stream across the northwestern tip of the ridge slowed shortly after. Using an ice-flow model capable of simulating shear margin migration, we evaluate whether small changes in ice thickness can lead to large changes in shear margin location. Our results suggest that the tip of Conway Ridge is sensitive to thinning and thickening, and that when the basal strength at the tip of the ridge increases with the height above flotation, the ice sheet shear margins can change quickly.
Perennially ice-covered lakes in the McMurdo Dry Valleys of Antarctica contain abundant microbial mats, and the export of this mat material can fertilize the surrounding polar desert ecosystems. These desert soils are one of the most organic-poor on earth yet host a community of microorganisms. Microbial mat material is exported from the shallow, gas-supersaturated regions of the lakes when gas bubbles form in the mats, lifting them to the ice cover; the perennial ice cover maintains gas supersaturation. These mats freeze in and are exported to the surrounding soils through ice ablation. The largest seasonal decrease and thinnest ice cover in the history of Lake Fryxell was recorded during the 2022-2023 Austral summer. In this thin ice year, the water column dissolved oxygen increased over prior observations, and the lake bottom surface area with bubble-disrupted mat was more than double that observed in 1980-1981 and 2006-2007. This work will constrain mat mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning to understand how future changing regional climate and predicted seasonal loss of lake ice cover will affect nutrient transport in the McMurdo Dry Valleys. Exceptional years of mat export are hypothesized to have the most significant impact on nutrient export to soil communities; variability in mat liftoff may thus play a role in the McMurdo Dry Valleys ecosystem response to changing climate. The perennial ice cover of lakes in the McMurdo Dry Valleys of Antarctica modulates the transfer of gasses, organic and inorganic material, between the lakes and surrounding soils. The export of biomass in these lakes is driven by the supersaturation of atmospheric gasses in the shallow regions under perennial ice cover. Gas bubbles nucleate in the mats, producing buoyancy that lifts them to the bottom of the ice, where they freeze in and are exported to the surrounding soils through ice ablation. These mats represent a significant source of biomass and nutrients to the McMurdo Dry Valleys soils, which are among the most organic-poor on earth. Nevertheless, this biomass remains unaccounted for in organic carbon cycling models for the McMurdo Dry Valleys. Ice cover data from the McMurdo Dry Valleys Long Term Ecological Research Project shows that the ice thickness has undergone cyclical variation over the last 40 years, reaching the largest seasonal decrease and thinnest ice-cover in the recorded history of Lake Fryxell during the 2022-2023 austral summer. Preliminary work shows that the surface area with mat liftoff at Lake Fryxell is more than double that observed in 1980-1981 and 2006-2007, coinciding with this unprecedented thinning of the ice-cover and an increase in the water column dissolved O2. This research will constrain biomass mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning. The researchers hypothesize that a thinner ice cover promotes more biomass mobilization by 1) stimulating additional production of gas bubbles from the existing gas-supersaturated waters during summertime photosynthesis to create microbial mat liftoff and 2) promoting mat liftoff in deeper, thicker microbial mats, and 3) that this biomass can be traced into the soils by characterizing its chemistry and modeling the most likely depositional settings. This work will use microbial mat samples, lake dissolved oxygen and photosynthetically active radiation data and underwater drone footage documenting the depth distribution of liftoff mats in January 2023, and long-term ice cover thickness, photosynthetically active radiation, and lake level change data collected by the McMurdo Dry Valleys Long Term Ecological Research Project to test hypotheses 1-3. The dispersal of the liftoff mat exposed at Lake Fryxell surface will be modeled using a Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Exceptional liftoff years like the present are hypothesized to have the most significant impact on the soil communities as the rates of soil respiration increase with the addition of carbon. However, continued warming in the next 10 - 40 years may result in seasonal loss of the ice cover and cessation of liftoff mat export. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function.<br/> <br/> <br/>To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys - these results have been uploaded to MAPPPD (penguinmap.com) and are freely available for use. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public.
Non-technical Abstract The McMurdo Dry Valleys LTER seeks to understand how changes in the temporal variability of ecological connectivity interact with existing landscape legacies to alter the structure and functioning of this extreme polar desert ecosystem. This research has broad implications, as it will help us to understand how natural ecosystems respond to ongoing anthropogenic global change. At the same time, this project also serves an important educational and outreach function, providing immersive research and educational experiences to students and artists from diverse backgrounds, and helping to ensure a diverse and well-trained next generation of leaders in polar ecosystem science and stewardship. Ultimately, the results of this project will help us to better understand and prepare for the effects of climate change and develop scientific insights that are relevant far beyond Antarctic ecosystems. The McMurdo Dry Valleys (MDVs) make up an extreme polar desert ecosystem in the largest ice-free region of Antarctica. The organisms in this ecosystem are generally small. Bacteria, microinvertebrates, cyanobacterial mats, and phytoplankton can be found across the streams, soils, glaciers, and ice-covered lakes. These organisms have adapted to the cold and arid conditions that prevail outside of lakes for all but a brief period in the austral summer when the ecosystem is connected by liquid water. In the summer when air temperatures rise barely above freezing, soils warm and glacial meltwater flows through streams into the open moats of lakes. Most biological activity across the landscape occurs in summer. Through the winter, or polar night (6 months of darkness), glaciers, streams, and soil biota are inactive until sufficient light, heat, and liquid water return, while lake communities remain active all year. Over the past 30 years, the MDVs have been disturbed by cooling, heatwaves, floods, rising lake levels, as well as permafrost and lake ice thaw. Considering the clear ecological responses to this variation in physical drivers, and climate models predicting further warming and more precipitation, the MDV ecosystem sits at a threshold between the current extreme cold and dry conditions and an uncertain future. This project seeks to determine how important the legacy of past events and conditions versus current physical and biological interactions shape the current ecosystem. Four hypotheses will be tested, related to 1) whether the status of specific organisms are indicative ecosystem stability, 2) the relationship between legacies of past events to current ecosystem resilience (resistance to big changes), 3) carryover of materials between times of high ecosystem connectivity and activity help to maintain ecosystem stability, and 4) changes in disturbances affect how this ecosystem persists through the annual polar night (i.e., extended period of dark and cold). Technical Abstract In this iteration of the McMurdo LTER project (MCM6), the project team will test ecological connectivity and stability theory in a system subject to strong physical drivers (geological legacies, extreme seasonality, and contemporary climate change) and driven by microbial organisms. Since microorganisms regulate most of the world’s critical biogeochemical functions, these insights will be relevant far beyond polar ecosystems and will inform understanding and expectations of how natural and managed ecosystems respond to ongoing anthropogenic global change. MCM6 builds on previous foundational research, both in Antarctica and within the LTER network, to consider the temporal aspects of connectivity and how it relates to ecosystem stability. The project will examine how changes in the temporal variability of ecological connectivity interact with the legacies of the existing landscape that have defined habitats and biogeochemical cycling for millennia. The project team hypothesizes that the structure and functioning of the MDV ecosystem is dependent upon legacies and the contemporary frequency, duration, and magnitude of ecological connectivity. This hypothesis will be tested with new and continuing monitoring, experiments, and analyses of long-term datasets to examine: 1) the stability of these ecosystems as reflected by sentinel taxa, 2) the relationship between ecological legacies and ecosystem resilience, 3) the importance of material carryover during periods of low connectivity to maintaining biological activity and community stability, and 4) how changes in disturbance dynamics disrupt ecological cycles through the polar night. Tests of these hypotheses will occur in field and modeling activities using new and long-term datasets already collected. New datasets resulting from field activities will be made freely available via widely-known online databases (MCM LTER and EDI). The project team has also developed six Antarctic Core Ideas that encompass themes from data literacy to polar food webs and form a consistent thread across the education and outreach activities. Building on past success, collaborations will be established with teachers and artists embedded within the science teams, who will work to develop educational modules with science content informed by direct experience and artistic expression. Undergraduate mentoring efforts will incorporate computational methods through a new data-intensive scientific training program for MCM REU students. The project will also establish an Antarctic Research Experience for Community College Students at CU Boulder, to provide an immersive educational and research experience for students from diverse backgrounds in community colleges. MCM LTER will continue its mission of training and mentoring students, postdocs, and early career scientists as the next generation of leaders in polar ecosystem science and stewardship. Historically underrepresented participation will be expanded at each level of the project. To aid in these efforts, the project has established Education & Outreach and Diversity, Equity, and Inclusion committees to lead, coordinate, support, and integrate these activities through all aspects of MCM6. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project is co-funded by a collaboration between the Directorate for Geosciences and Office of Advanced Cyberinfrastructure to support Artificial Intelligence/Machine Learning and open science activities in the geosciences. Machine learning model will be used in this project to predict the distributions of five zooplankton species in the western Antarctic Peninsula (wAP) based on oceanographic properties. The project will take advantage of a long-term series collected by the Palmer Long-Term Ecological Research (LTER) program that collects annual data on physics, chemistry, phytoplankton (or food), zooplankton and predators (seabirds, whales and seals). By analyzing this dataset and combining it with other data collected by national and international programs, this project will provide understanding and prediction of zooplankton distribution and abundance in the wAP. The machine learning models will be based on environmental properties extracted from remote sensing images thus providing ecosystem knowledge as it decreases human footprint in Antarctica. The relationship between species distribution and habitat are key for distinguishing natural variability from climate impacts on zooplankton and their predators. This research benefits NSF mission by expanding fundamental knowledge of Antarctic systems, biota, and processes as well as aligning with data and sample reuse strategies in Polar Research. The project will benefit society by supporting two female early-career scientists, a post-doctoral fellow and a graduate student. Polar literacy will be promoted through an existing partnership with Out Of School activities that target Science, Technology, Engineering and Mathematics (STEM) education, expected to reach 120,000 students from under-represented minorities in STEM annually. The project will also contribute to evaluate the ecosystem in the proposed Marine Protected Area in the wAP, subject to krill fishery. Results will be made available publicly through an interactive web application. The Principal Investigators propose to address three main questions: 1) Can geomorphic features, winter preconditioning and summer ocean conditions be used to predict the austral summer distribution of zooplankton species along the wAP? 2) What are the spatial and temporal patterns in modeled zooplankton species distribution along the wAP? And 3) What are the patterns of overlap in zooplankton and predator species? The model will generate functional relationships between zooplankton distribution and environmental variables and provide Zooplankton Distribution Models (ZDMs) along the Antarctic Peninsula. The Palmer LTER database will be combined with the NOAA AMLR data for the northern wAP, and KRILLBASE, made public by the British Antarctic Survey’s Polar Data Center. This project will generate 1) annual environmental spatial layers on the Palmer LTER resolution grid within the study region, 2) annual species-specific standardized zooplankton net data from different surveys, 3) annual species-specific predator sightings on a standardized grid, and 4) ecological model output. Ecological model output will include annual predictions of zooplankton species distributions, consisting of 3-dimensional fields (x,y,t) for the 5 main zooplankton groups, including Antarctic krill, salps and pteropods. Predictions will be derived from merging in situ survey data with environmental data, collected in situ or by remote sensing. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part 1: Non-technical description The goal of all LTER sites is to conduct policy-relevant ecosystem research for questions that require tens of years of data and cover large geographical areas. The Palmer Antarctica Long Term Ecological Research (PAL-LTER) site has been in operation since 1990 and has been studying how the marine ecosystem west of the Antarctica Peninsula (WAP) is responding to a climate that is changing as rapidly as any place on the Earth. The study is evaluating how warming conditions and decreased ice cover leading to extended periods of open water are affecting many aspects of ecosystem function. The team is using combined cutting-edge approaches including yearly ship-based research cruises, small-boat weekly sampling, autonomous vehicles, animal biologging, oceanographic floats and seafloor moorings, manipulative lab-based process studies and modeling to evaluate both seasonal and annual ecosystem responses. These combined approaches are allowing for the study the ecosystem changes at scales needed to assess both short-term and long-term drivers. The study region also includes submarine canyons that are special regions of enhanced biological activity within the WAP. This research program is paired with a comprehensive education and outreach program promoting the global significance of Antarctic science and research. In addition to training for graduate and undergraduate students, they are using newly-developed Polar Literacy Principles as a foundation in a virtual schoolyard program that shares polar instructional materials and provides learning opportunities for K-12 educators. The PAL-LTER team is also leveraging the development of Out of School Time materials for afterschool and summer camp programs, sharing Palmer LTER-specific teaching materials with University, Museum, and 4-H Special Interest Club partners. Part 2: Technical description Polar ecosystems are among the most rapidly changing on Earth. The Palmer LTER (PAL-LTER) program builds on three decades of coordinated research along the western side of the Antarctic Peninsula (WAP) to gain new mechanistic and predictive understanding of ecosystem changes in response to disturbances spanning long-term decadal (‘press’) drivers and changes due to higher-frequency (‘pulse’) drivers, such as large storms and extreme seasonal anomaly in sea ice cover. The influence of major natural climate modes that modulate variations in sea ice, weather, and oceanographic conditions to drive changes in ecosystem structure and function (e.g., El Niño Southern Oscillation and Southern Annular Mode) are being studied at multiple time scales –from diel, seasonal, interannual, to decadal intervals, and space scales–from hemispheric to global scale investigated by remote sensing, the regional scales. Specifically, the team is evaluating how variability of physical properties (such as vertical and alongshore connectivity processes) interact to modulate biogeochemical cycling and community ecology in the WAP region. The study is providing an evaluation of ecosystem resilience and ecological responses to long-term “press-pulse” drivers and a decadal-level reversal in sea ice coverage. This program is providing fundamental understanding of population and biogeochemical responses for a marine ecosystem experiencing profound change. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Sea ice in Antarctic coastal waters shape ecosystems, both in the surface waters and at the bottom of the ocean, environments that depend on algae living in sea ice for their productivity. With high variability in sea ice formation and melt between years and as a response to climate change, it is of importance to obtain better understanding of the interaction of sea ice with algae, as well as provide better data for global climate models. This project will accomplish those goals by measuring phytoplankton growth and cellular properties in sea ice with experiments performed using an ice tank. Laboratory experiments will be based on previous observations in the Antarctic Peninsula coastal waters, providing realistic conditions to emulate. The scientific importance of the proposed work aligns with the National Science Foundation goals to understand the biological and chemical properties of sea ice bio-geo-chemistry and its feedbacks with seasonal sea ice dynamics and climate. The finding from this project will be of interest to a broad scientific community, including oceanographers, biologists, chemists, and ecosystem and ocean modelers. To address the scarcity of data on sea ice microbes that limits our ability to predict future Antarctic climate with accuracy, the principal investigator will develop an Antarctic Science Minor in order to train future scientists with an environmental perspective and prepare the future US workforce with a strong scientific background on Earth and Biological Sciences. There is a paucity of data to understand the processes underlying observed patters in sea ice quality and their interaction with the sea-ice microbial community. This project will provide a mechanistic understanding of primary production and physiology of sympagic algae over the seasonal cycle of formation and melt of Antarctic sea ice. Although sea ice is central to the Antarctic coastal ecosystems, little is known of how they affect, and are in turn affected, by sea-ice algae. This project concentrates on first-year sea ice, forming and melting each year, creating unique and very dynamic habitats. The study will be structured by 4 main objectives: 1) how different algal species adapt to the seasonal changes in sea ice conditions, 2) how different methods to measure primary production (carbon dioxide drawdown, oxygen production and variable fluorescence) relate in sea ice and differ from sea water measurements, 3) how sympagic algae influence the physical structure of sea ice, 4) how sympagic algae contribute to organic matter cycling during ice melt. Due to expected changes in sea ice due to climate change, this study is uniquely positioned to provide needed data on short-term and seasonal processes. Results from this study will be useful to refine models of algal production in Antarctic and Arctic ecosystems, data not available to date as sea ice and its biogeochemistry are often poorly represented in earth system models. This project will also provide education for graduate and undergraduate students as well as material to develop class curriculum for middle-school students. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica’s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica’s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth's most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change. The proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica’s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part 1: On frequent crossings of the Drake Passage on the US Antarctic vessel ARSV Laurence M. Gould, a range of underway measurements are taken. These data represent one of the few repeat year around shipboard measurements in the Southern Ocean. With close to two decades of data now available, the primary science objectives of this proposal are to continue to analyze the Drake Passage time series. Part 2: Some of the analyses are (1) describe and relate the seasonal and long-term ocean energy distribution to wind, buoyancy and topographic forcing and sinks, and (2) describe and relate seasonal and long-term changes in the ACC fronts, water masses and upwelling to biogeochemical and climate variability. High-resolution, near-repeat Expendable Bathythermograph (XBT) and Acoustic Doppler Current Profiler (ADCP) transect sampling in Drake Passage is thus used to study modes of variability in ocean temperature, salinity, currents and backscatter in the Antarctic Circumpolar Current (ACC) on seasonal to interannual time frames, and on space scales from current cores to eddies. This project is a continuation of the longstanding support for collecting the ADCP and other underway data on USAP vessels, such as the ASRV Laurence M Gould This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Southern Ocean plays a key role in modulating the global carbon cycle, but the size and even the sign of the global ocean flux terms of the atmospheric burden of man-made CO2 are still uncertain. This is in part due to the lack of measurements in this remote region of the world ocean. This project continues a multi-year time series of shipboard chemical measurements in the Drake Passage to detect changes in the ocean carbon cycle and to improve the understanding of mechanisms driving natural variability and long-term change in the Southern Ocean. This project is a continuation of collection of upper ocean measurements of the underway surface partial pressure of carbon dioxide (pCO2), using frequent ferry crossings of the Drake Passage by the RV/AS LMGould, the USAP supply ship. Overall, more than 200 transects over the past decade (since 2002) have now been accumulated of pCO2 profiles, along with discrete samples for other parameters of interest in studying the ocean carbonate system such as total CO2 (TCO2) values, isotopic (13C/12C and 14C/12C) ratios in surface TCO2. The Drake Passage data are made readily available to the international science community and serve as both validation and constraints of remotely sensed observations and numerical coupled earth systems models.
In the austral winter of 2021/2022 a drastic decline in Antarctic sea ice extent has taken place, and February 2022 marked the lowest sea ice extent on record since satellite sea ice observations began in 1979. Combined with the loss of sea ice, the most extreme heat wave ever observed took place over East Antarctica in March 2022 as temperatures climbed over +40°C from climatology. Extreme events have an oversized footprint in socioeconomic impacts, but also serve as litmus tests for climate predictions. This project will use novel tools to diagnose the factors that led to the record low Antarctic sea ice extent and heat wave focusing on the impact of winds and ocean temperatures. Currently (June 2022) Antarctic sea ice extent remains at record low levels for the time of year, raising the prospect of a long-lasting period of low sea ice extent, yet annual forecasts of Antarctic sea ice do not yet exist. To address this issue, this project will also create exploratory annual sea ice forecasts for the 2022-2024 period. The extreme changes observed in Antarctic sea ice extent and air temperature have questioned our current understanding of Antarctic climate variability. Motivated by the timing of these events and our recent development of novel analysis tools, this project will address the following research questions: (R1) Can local winds account for the observed 2021/2022 sea ice loss, or are remote sea surface temperature (SST) anomalies a necessary ingredient? (R2) Are sea ice conditions over 2022-2024 likely to remain anomalously low? (R3) Can a state-of-the-art climate model simulate a heat wave of comparable magnitude to that observed if it follows the observed circulation that led to the heat wave? The main approach will be to use a nudging technique with a climate model, in which one or several variables in a climate model are nudged toward observed values. The project authors used this tool to attribute Antarctic sea ice variability and trends over 1979-2018 to winds and SST anomalies. This project will apply this tool to the period 2019-2022 to address R1 and R3 by running two different model experiments over this time period in which the winds over Antarctica and SSTs in the Southern Ocean are nudged toward observed values. In addition, we will diagnose the relevant modes of atmospheric variability over 2019-2022 that are known to influence Antarctic sea ice to gain further insight into the 2022 loss of sea ice extent. To address R2, we plan to extend the model simulations but without nudging, using the model as a forecast model (as its 2022 initial conditions will be taken from the end of the nudged simulations and capture important aspects of the observed state). We expect that if current upper ocean heat content is anomalously high, low sea ice extent conditions may continue over 2022-2024, as happened over 2017-2019 following the previous record low of sea ice extent in 2016/2017. To further address R3, we will compare observations and model simulations using novel atmospheric heat transport calculations developed by the project team. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Earth's atmosphere is a highly oxidizing medium. The abundance of oxidants such as ozone in the atmosphere strongly influences the concentrations of pollutants and greenhouse gases, with implications for human health and welfare. Because oxidants are not preserved in geological archives, knowledge of how oxidants have varied in the past under changing climate conditions is extremely limited. This award will measure a proxy for oxidant concentrations in a West Antarctic ice core over several major climate transitions over the past 50,000 years. These measurements will complement similar measurements from a Greenland ice core, which showed significant changes in atmospheric oxidants over major climate transitions covering this same time period. The addition of measurements from Antarctica will allow researchers to examine if the oxidant changes suggested by the Greenland ice core record are regional or global in scale. Knowledge of how oxidants vary naturally with climate will better inform predictions of the composition of the future atmosphere under a warming climate. This award will support measurements of the isotopic composition of nitrate in a West Antarctic ice core as a proxy for oxidant concentrations in the past atmosphere. The nitrogen isotopes of nitrate provide information on the degree of preservation of nitrate in the ice core record, and thus aid in the interpretation of the observed variability in the observed nitrate concentrations and oxygen isotopes in ice core records. By providing information about the spatial scale of oxidant changes over abrupt climate change events during the last glacial period, this project may also improve our understanding of mechanisms driving these abrupt events. Insight from this project will prove valuable for forecasting the response of stratospheric circulation to climate change, which has large implications for climate feedbacks and tropospheric composition. In addition, the information gleaned from this project on the mechanisms and feedbacks during abrupt climate change events will help determine the likelihood of such rapid events occurring in the future, which would have dramatic impacts on humankind. This award will provide training for one graduate and one undergraduate student, and will support the development of a hands-on activity related to rapid climate change to be used at the annual Polar Science Weekend at the Pacific Science Center in Seattle, WA.
Kienle, Sarah; Trumble, Stephen J; Bonin, Carolina
No dataset link provided
The leopard seal (Hydrurga leptonyx) is an enigmatic apex predator in the rapidly changing Southern Ocean. As top predators, leopard seals play a disproportionately large role in ecosystem functioning and act as sentinel species that can track habitat changes. How leopard seals respond to a warming environment depends on their adaptive capacity, that is a species’ ability to cope with environmental change. However, leopard seals are one of the least studied apex predators on Earth, hindering our ability to predict how the species is responding to polar environmental changes. Investigating the adaptability of Antarctic biota in a changing system aligns with NSF’s Strategic Vision for Investments in Antarctic and Southern Ocean Research. This research, which is tightly integrated with educational and outreach activities, will increase diversity in STEM and Antarctic science by recruiting students from historically underrepresented groups in STEM and providing training, mentoring, and educational opportunities at an emerging Hispanic Serving Institution and a Historically Black Colleges and Universities campus. This project will improve STEM education and science literacy via museum collaborations, creation of informational videos and original artwork depicting the research. The proposal supports data and sample reuse in polar research and long-term reuse of scientific data, thereby maximizing NSF’s investment in previous field research and reducing operational costs. The researchers will investigate leopard seals adaptive capacity to the warming Southern Ocean by quantifying their ability to move (dispersal ability), adapt (genetic diversity), and change (plasticity). Aim 1 of the research will determine leopard seals’ dispersal ability by assessing their distribution and movement patterns. Aim 2 will quantify genetic diversity by analyzing genetic variability and population structure and Aim 3 will examine phenotypic plasticity by evaluating changes in their ecological niche and physiological responses. The international, multidisciplinary team will analyze existing data (e.g., photographs, census data, life history data, tissue samples, body morphometrics) collected from leopard seals across the Southern Ocean over the last decade. Additionally, land- and ship-based field efforts will generate comparable data from unsampled regions in the Southern Ocean. The research project will analyze these historical and contemporary datasets to evaluate the adaptive capacity of leopard seals against the rapidly warming Southern Ocean. This research is significant because changes in the distribution, genetic diversity, and ecophysiology of leopard seals can dramatically restructure polar and subpolar communities. Further, the research will expand understanding of leopard seals’ ecological role, likely characterizing the species as flexible polar and subpolar predators throughout the Southern Hemisphere. The findings of this research will be relevant for use in ecosystem-based management decisions—including the design of Marine Protected Areas— across three continents. This study will highlight intrinsic traits that determine species’ adaptive capacity, as well as showcase the dynamic links between polar and subpolar ecosystems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Microbes in Antarctic surface marine sediments have an important role in degrading organic matter and releasing nutrients to the ocean. Organic matter degradation is at the center of the carbon cycle in the ocean, providing valuable information on nutrient recycling, food availability to animals and carbon dioxide release to the atmosphere. The functionality of these microbes has been inferred by their genomics, however these methods only address the possible function, not their actual rates. In this project the PIs plan to combine genomics methods with cellular estimates of enzyme abundance and activity as a way to determine the rates of carbon degradation. This project aims to sample in several regions of Antarctica to provide a large-scale picture of the processes under study and understand the importance of microbial community composition and environmental factors, such as primary productivity, have on microbial activity. The proposed work will combine research tools such as metagenomics, meta-transcriptomics, and metabolomics coupled with chemical data and enzyme assays to establish degradation of organic matter in Antarctic sediments. This project benefits NSFs goals of understanding the adaptation of Antarctic organisms to the cold and isolated environment, critical to predict effects of climate change to polar organisms, as well as contribute to our knowledge of how Antarctic organisms have adapted to this environment. Society will benefit from this project by education of 2 graduate students, undergraduates and K-12 students as well as increase public literacy through short videos production shared in YouTube. The PIs propose to advance understanding of polar microbial community function, by measuring enzyme and gene function of complex organic matter degradation in several ocean regions, providing a circum-Antarctic description of sediment processes. Two hypotheses are proposed. The first hypothesis states that many genes for the degradation of complex organic matter will be shared in sediments throughout a sampling transect and that where variations in gene content occur, it will reflect differences in the quantity and quality of organic matter, not regional variability. The second hypothesis states that a fraction of gene transcripts for organic matter degradation will not result in measurable enzyme activity due to post-translational modification or rapid degradation of the enzymes. The PIs will analyze sediment cores already collected in a 2020 cruise to the western Antarctic Peninsula with the additional request of participating in a cruise in 2023 to East Antarctica. The PIs will analyze sediments for metagenomics, meta-transcriptomics, and metabolomics coupled with geochemical data and enzyme assays to establish microbial degradation of complex organic matter in Antarctic sediments. Organic carbon concentrations and content in sediments will be measured with δ13C, δ15N, TOC porewater fluorescence in bulk organic carbon. Combined with determination of geographical variability as well as dependence on carbon sources, results from this study could provide the basis for new hypotheses on how climate variability, with increased water temperature, affects geochemistry in the Southern Ocean. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Antarctic Automatic Weather Station network is the most extensive surficial meteorological network in the Antarctic, approaching its 30th year at several of its data stations. Its prime focus is also as a long term observational record, to measure the near surface weather and climatology of the Antarctic atmosphere. Antarctic Automatic Weather Stations measure air-temperature, pressure, wind speed and direction at a nominal surface height of ~ 2-3m. Other parameters such as relative humidity and snow accumulation may also be taken. The surface observations from the Antarctic Automatic Weather Station network are also used operationally, for forecast purposes, and in the planning of field work. Surface observations made from the network have also been used to check the validity of satellite and remote sensing observations. The proposed effort informs our understanding of the Antarctic environment and its weather and climate trends over the past few decades. The research has implications for potential future operations and logistics for the US Antarctic Program during the winter season. As a part of this endeavor, all project participants will engage in a coordinated outreach effort to bring the famous Antarctic "cold" to public seminars, K-12, undergraduate, and graduate classrooms, and senior citizen centers. This project proposes to use the surface conditions observed by the Antarctic Automatic Weather Station (AWS) network to determine how large-scale modes of climate variability impact Antarctic weather and climate, how the surface observations from the AWS network are linked to surface layer and boundary layer processes. Consideration will also be given to low temperature physical environments such as may be encountered during Antarctic winter, and the best ways to characterize these, and other ?cold pool? phenomena. Observational data from the AWS are collected via Iridium network, or DCS Argos aboard either NOAA or MetOp polar orbiting satellites and thus made available in near real time to operational and synoptic weather forecasters over the GTS (WMO Global Telecommunication System). Being able to support improvements in numerical weather prediction and climate modeling will have lasting impacts on Antarctic science and logistical support. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Antarctic Automatic Weather Station network is the most extensive surficial meteorological network in the Antarctic, approaching its 30th year at several of its data stations. Its prime focus is also as a long term observational record, to measure the near surface weather and climatology of the Antarctic atmosphere. Antarctic Automatic Weather Stations measure air-temperature, pressure, wind speed and direction at a nominal surface height of ~ 2-3m. Other parameters such as relative humidity and snow accumulation may also be taken. The surface observations from the Antarctic Automatic Weather Station network are also used operationally, for forecast purposes, and in the planning of field work. Surface observations made from the network have also been used to check the validity of satellite and remote sensing observations. The proposed effort informs our understanding of the Antarctic environment and its weather and climate trends over the past few decades. The research has implications for potential future operations and logistics for the US Antarctic Program during the winter season. As a part of this endeavor, all project participants will engage in a coordinated outreach effort to bring the famous Antarctic "cold" to public seminars, K-12, undergraduate, and graduate classrooms, and senior citizen centers.<br/><br/>This project proposes to use the surface conditions observed by the Antarctic Automatic Weather Station (AWS) network to determine how large-scale modes of climate variability impact Antarctic weather and climate, how the surface observations from the AWS network are linked to surface layer and boundary layer processes. Consideration will also be given to low temperature physical environments such as may be encountered during Antarctic winter, and the best ways to characterize these, and other ?cold pool? phenomena. Observational data from the AWS are collected via Iridium network, or DCS Argos aboard either NOAA or MetOp polar orbiting satellites and thus made available in near real time to operational and synoptic weather forecasters over the GTS (WMO Global Telecommunication System). Being able to support improvements in numerical weather prediction and climate modeling will have lasting impacts on Antarctic science and logistical support.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Walker, Catherine; Zhang, Weifeng; Seroussi, Helene
No dataset link provided
Most of the mass loss from the Antarctic Ice Sheet, a major contributor to sea level rise, occurs at its margins, where ice meets the ocean. Glaciers and ice streams flow towards the coast and can go afloat over the water, forming ice shelves. Ice shelves make up almost half of the entire Antarctic coastline, and hold back the flow of inland ice in Antarctica continent; thus they are integral to the overall stability of the Antarctic Ice Sheet. Ice shelves lose mass by two main processes: iceberg calving and basal melting. Temporal and spatial fluctuations in both are driven by various processes; a major driver of ice shelf melt is the heat provided by the neighboring Southern Ocean. Ocean heat, in turn, is driven by various aspects of the ice shelf environment. One of the most significant contributors to changes in the ocean’s heat content is the presence of sea ice. This research will focus on the effects of coastal polynyas (areas of open water amidst sea ice), how they modulate the local ocean environment, and how that environment drives ice shelf basal melting. To date, the relationship between polynyas and ice shelf melt has not been characterized on an Antarctic-wide scale. Understanding the feedbacks between polynya size and duration, ocean stratification, and ice shelf melt, and the strength of those feedbacks, will improve the ability to characterize influences on the long-term stability of ice shelves, and in turn, the Antarctic Ice Sheet as a whole. A critical aspect of this study is that it will provide a framework for understanding ice shelf-ocean interaction across a diverse range of geographic settings. This, together with improvements of various models, will help interpret the impacts of future climate change on these systems, as their responses are likely quite variable and, overall, different from the large-scale response of the ice sheet. This project will also provide a broader context to better design future observational studies of specific coastal polynya and ice shelf processes. This study focuses on four main hypotheses: 1) Variations of coastal polynya extent are correlated with those of the ice shelf melt rates, and this correlation varies around Antarctica; 2) Polynya extent modulates a feedback between ice shelf melt and accretion regimes through stratification of local waters; 3) Polynya extent together with seafloor bathymetry regulate the volume of warm offshore waters that reach ice margins; and 4) The strength of the feedback between polynya and glacier ice varies with geographic setting and influences the long-term stability of the glacial system. Observational data, including ice-penetrating radar, radar and laser altimetry, and in situ hydrographic data, and derived data sets from the Southern Ocean State Estimate (SOSE) project and BedMachine Antarctica, will be used in conjunction with ocean (MIT global circulation model, MITgcm) and ice sheet (Ice sheet and Sea-level System Model, ISSM) models to reveal underlying dynamics. The joint analysis of the observational data enables an investigation of polynya, ocean, and ice shelf signals and their interplay over time across a range of settings. The results of this data analysis also provide inputs and validation data for the modeling tasks, which will allow for characterization of the feedbacks in our observations. The coupled modeling will enable us to examine the interaction between polynya circulation and ice shelves in different dynamical regimes and to understand ice and ocean feedback over time. Diagnosing and interpreting the pan-Antarctic spatial variability of the polynya-ice shelf interaction are the main objectives of this research and separates this study from other projects targeted at the interactive processes in specific regions. As such, this research focuses on seven preliminary target sites around the Antarctic coast to establish a framework for interpreting coupled ice shelf-ocean variability across a diverse range of geographic settings. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Non-Technical Description: Snow accumulation in the interior of the Antarctic Ice Sheet, and how much snow is redistributed by wind are important components of the climate system of Antarctica, yet remain largely unknown. Because of the extreme meteorological conditions found in Antarctica, direct observations of snowfall and related weather are few, leaving a gap in the regional climate records in the continent. Snow accumulation across the Antarctic Ice Sheet is a critical component for the assessment of the contribution of Antarctica to sea level rise, and accurate measurements are required to evaluate results from regional climate models, used to reconstruct climate trends of the recent past for the whole ice sheet. Owing to the size of Antarctica alone, small fluctuations in the total snow accumulation at the surface have a significant effect on the mass budget of the ice sheet and thus on global sea level. In this work will develop an instrument suite for deployment at the South Pole research station in Antarctica. The monitoring station will have new state-of-the-art sensors will record measurements of weather, snow accumulation, and structural conditions within the layer of packed snow. The autonomous system will be tested in the coldest and darkest winter on the planet, and will provide the first continuous measurements of snow accumulation processes in the interior of the ice sheet, which will be used to validate atmospheric and regional climate models. Technical Description: The overarching goal of the proposed work is to improve our understanding of the spatiotemporal variability in ice-sheet surface mass balance and densification rates within the layer of firn, a layer roughly 100 m thick consisting of the buried and compacted snow that has yet to densify into solid ice. For this, we will A) design and install a cost-efficient, reliable, and easily deployable surface mass balance and firn monitoring system for Antarctica; B) adapt the system to operate autonomously for long periods of time under the harshest meteorological conditions; C) use observations for evaluation of surface mass balance simulated by atmospheric reanalyzes and regional climate model; and D) measure the surface mass balance, surface density, and firn compaction rates to derive ice sheet surface elevation change in areas with low ice dynamics. The set up of the monitoring station is unique in that it is able to monitor separately height change due to surface mass balance variability and absolute surface mass balance, the latter in units of water equivalence, and differentiation of the two is crucial for understanding the role of surface processes in ice sheet mass balance. An installed sonic ranger will provide hourly measurements of surface height change that is due to snow accumulation. Surface height change alone is not sufficient to evaluate atmospheric models of surface mass balance, which is measured in in units of mass; a key variable missing is density. To overcome this, the system will be equipped with a SnowFox sensor that is able to capture the variations in surface mass balance in terms of mass through time. Combining the height change with mass change will allow us to determine the density of the material as well, which is very important for conversion of observed height changes due to surface processes into mass changes. Therefore, we aim to better evaluate the short-term variability in surface height and mass fluctuations due to surface mass balance to improve our understanding of the total mass change and to evaluate atmospheric models, which are typically used for ice sheet-wide mass balance studies.
Sea-ice coverage surrounding Antarctica has expanded during the era of satellite observations, in contrast to rapidly shrinking Arctic sea ice. Most climate models predict Antarctic sea ice loss, rather than growth, indicating that there is much to learn about Antarctic sea ice in terms of its natural variability, processes and interactions affecting annual growth and retreat, and the impact of atmospheric factors such increasing greenhouse gases and stratospheric ozone depletion. This project is designed to improve model simulations of sea ice and examine the role of wind and wave forcing on changes in sea ice around Antarctica. This project seeks to explain basic interactions of the coupled atmosphere, ocean, and ice dynamics in the Antarctic climate system, especially in the region near the sea ice edge. The summer evolution of sea ice cover and the near surface heat exchange of atmosphere and ocean depend on the geometric distribution of floes and the open water surrounding them. The distribution of floes has the greatest impact on the sea ice state in the marginal seas, where the distribution itself can vary rapidly. This project would develop and implement a model of sea ice floes in the Los Alamos sea ice model, known as CICE5. This sea ice component would be coupled to the third generation WaveWatch model within the Community Climate System Model Version 2. The coupled model would be used to study sea ice-wave interactions and the role of modeling sea ice floes in the Antarctic. The broader impacts of this project include outreach, support of female scientists, and improvement of the sea-ice codes in widely used climate models.
This research project will use specially designed autonomous underwater vehicles (AUVs) to investigate interactions between Adelie and Gentoo penguins (the predators) and their primary food source, Antarctic krill (prey). While it has long been known that penguins feed on krill, details about how they search for food and target individual prey items is less well understood. Krill aggregate in large swarms, and the size or the depth of these swarms may influence the feeding behavior of penguins. Similarly, penguin feeding behaviors may differ based on characteristics of the environment, krill swarms, and the presence of other prey and predator species. This project will use specialized smart AUVs to simultaneously collect high-resolution observations of penguins, their prey, and environmental conditions. Data will shed light on strategies used by penguins prove foraging success during the critical summer chick-rearing period. This will improve predictions of how penguin populations may respond to changing environmental conditions in the rapidly warming Western Antarctic Peninsula region. Greater understanding of how individual behaviors shape food web structure can also inform conservation and management efforts in other marine ecosystems. This project has a robust public education and outreach plan linked with the Birch and Monterey Bay Aquariums. Previous studies have shown that sub-mesoscale variability (1-10 km) in Antarctic krill densities and structure impact the foraging behavior of air-breathing predators. However, there is little understanding of how krill aggregation characteristics are linked to abundance on fine spatial scales, how these patterns are influenced by the habitat, or how prey characteristics influences the foraging behavior of predators. These data gaps remain because it is extremely challenging to collect detailed data on predators and prey simultaneously at the scale of an individual krill patch and single foraging event. Building on previously successful efforts, this project will integrate echosounders into autonomous underwater vehicles (AUVs), so that oceanographic variables and multi-frequency acoustic scattering from both prey and penguins can be collected simultaneously. This will allow for quantification of the environment at the scale of individual foraging events made by penguins during the critical 50+ day chick-rearing period. Work will be centered near Palmer Station, where long-term studies have provided significant insight into predator and prey population trends. The new data to be collected by this project will test hypotheses about how penguin prey selection and foraging behaviors are influenced by physical and biological features of their ocean habitat at extremely fine scale. By addressing the dynamic relationship between individual penguins, their prey, and habitat at the scale of individual foraging events, this study will begin to reveal the important processes regulating resource availability and identify what makes this region a profitable foraging habitat and breeding location. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function. To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Hydroxyl radicals are responsible for removal of most atmospheric trace gases, including pollutants and important greenhouse gases. They have been called the "detergent of the atmosphere". Changes in hydroxyl radical concentration in response to large changes in reactive trace gas emissions, which may happen in the future, are uncertain. This project aims to provide the first estimates of the variability of atmospheric hydroxyl radicals since about 1880 AD when anthropogenic emissions of reactive trace gases were minimal. This will improve understanding of their stability in response to large changes in emissions. The project will also investigate whether ice cores record past changes in Southern Hemisphere westerly winds. These winds are a key component of the global climate system, and have an important influence on ocean circulation and possibly on atmospheric carbon dioxide concentrations. The project team will include three early career scientists, a postdoctoral researcher, and graduate and undergraduate students, working in collaboration with senior scientists and Australian collaborators. Firn air and shallow ice to a depth of about 233 m will be sampled at the Law Dome high-accumulation coastal site in East Antarctica. Trapped air will be extracted from the ice cores on site immediately after drilling. Carbon-14 of carbon monoxide (14CO) will be analyzed in firn and ice-core air samples. Corrections will be made for the in situ cosmogenic 14CO component in the ice, allowing for the atmospheric 14CO history to be reconstructed. This 14CO history will be interpreted with the aid of a chemistry-transport model to place the first observational constraints on the variability of Southern Hemisphere hydroxyl radical concentration after about 1880 AD. An additional component of the project will analyze Krypton-86 in the firn-air and ice-core samples. These measurements will explore whether ice-core Krypton-86 acts as a proxy for barometric pressure variability, and whether this proxy can be used in Antarctic ice cores to infer past movement of the Southern Hemisphere westerly winds. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Warming on the western Antarctic Peninsula in the later 20th century has caused widespread changes in the cryosphere (ice and snow) and terrestrial ecosystems. These recent changes along with longer-term climate and ecosystem histories will be deciphered using peat deposits. Peat accumulation can be used to assess the rate of glacial retreat and provide insight into ecological processes on newly deglaciated landscapes in the Antarctic Peninsula. This project builds on data suggesting recent ecosystem transformations that are linked to past climate of the western Antarctic Peninsula and provide a timeline to assess the extent and rate of recent glacial change. The study will produce a climate record for the coastal low-elevation terrestrial region, which will refine the major climate shifts of up to 6 degrees C in the recent past (last 12,000 years). A novel terrestrial record of the recent glacial history will provide insight into observed changes in climate and sea-ice dynamics in the western Antarctic Peninsula and allow for comparison with off-shore climate records captured in sediments. Observations and discoveries from this project will be disseminated to local schools and science centers. The project provides training and career development for a postdoctoral scientist as well as graduate and undergraduate students. The research presents a new systematic survey to reconstruct ecosystem and climate change for the coastal low-elevation areas on the western Antarctic Peninsula (AP) using proxy records preserved in late Holocene peat deposits. Moss and peat samples will be collected and analyzed to generate a comprehensive data set of late-Holocene climate change and ecosystem dynamics. The goal is to document and understand the transformations of landscape and terrestrial ecosystems on the western AP during the late Holocene. The testable hypothesis is that coastal regions have experienced greater climate variability than evidenced in ice-core records and that past warmth has facilitated dramatic ecosystem and cryosphere response. A primary product of the project is a robust reconstruction of late Holocene climate changes for coastal low-elevation terrestrial areas using multiple lines of evidence from peat-based biological and geochemical proxies, which will be used to compare with climate records derived from marine sediments and ice cores from the AP region. These data will be used to test several ideas related to novel peat-forming ecosystems (such as Antarctic hairgrass bogs) in past warmer climates and climate controls over ecosystem establishment and migration to help assess the nature of the Little Ice Age cooling and cryosphere response. The chronology of peat cores will be established by radiocarbon dating of macrofossils and Bayesian modeling. The high-resolution time series of ecosystem and climate changes will help put the observed recent changes into a long-term context to bridge climate dynamics over different time scales. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project will use observations and coupled climate model simulations to examine the causes of sea ice variability. Sea ice in the Southern Ocean has increased in area over the observational record but researchers have yet to agree on the cause. Researchers suggests that changes in surface winds, upper-ocean freshening, or internal ocean/atmosphere variability could be the main driver for the increase in sea ice area. This project will determine how much of the change in sea ice area from year to year is due to oceanic, atmospheric, and radiative processes. Reconciling the observation-based understanding with model representations of sea ice variability will improve confidence in projections of future changes in Southern Ocean sea ice. The goal of this proposal is to improve our understanding of the processes that drive Southern Ocean sea ice year-to-year variability and long term trends. This knowledge will provide insight into how Southern Ocean sea ice responded to greenhouse gas and ozone forcing in the past and how it will respond in the future. The energy budget of the coupled cryosphere/ocean/atmosphere climate system will be used as a framework to disentangle drivers and responses during sea ice loss events. The technique consists of: (i) calculating the coupled energy budget of the climate system at the monthly timescale, (ii) isolating the radiative impact of sea ice variability from the radiative impact of cloud variability in the observed satellite radiation record and (iii) analyzing the vertical structure of atmospheric energy transport to determine the vertical profile of energy transport into the atmospheric column. This framework will allow the investigators to distinguish whether ice loss events are triggered by oceanic processes, atmospheric dynamics, or radiative processes. Preliminary results show that a diversity of mechanisms can drive Southern Ocean sea ice variability in coupled climate models whereas observed sea ice variability appears to be dominated by atmospheric dynamics. The exploration of biases between models and observations in both the mean state and in specific processes will yield more accurate projections of the future of sea ice in the Southern Ocean.
Algae in the surface ocean convert carbon dioxide into organic carbon through photosynthesis. The biological carbon pump transports this organic carbon from the atmosphere to the deep ocean where it can be stored for tens to hundreds of years. Annually, the amount transported is similar to that humans are currently emitting by burning fossil fuels. However, at present we cannot predict how this important process will change with a warming ocean. These investigators plan to develop a 15+ year time-series of vertical carbon transfer for the Western Antarctic Peninsula; a highly productive Antarctic ecosystem. This region is also rapid transition to warmer temperatures leading to reduced sea ice coverage. This work will help researchers better understand how the carbon cycle in the Western Antarctic Peninsula will respond to climate change. The researchers will develop the first large-scale time-series of carbon flux anywhere in the ocean. This research will also support the education and training of a graduate student and support the integration of concepts in Antarctic research into two undergraduate courses designed for non-science majors and advanced earth science students. The researchers will also develop educational modules for introducing elementary and middle-school age students to important concepts such as gross and net primary productivity, feedbacks in the marine and atmospheric systems, and the differences between correlation and causation. Results from this proposal will also be incorporated into a children’s book, “Plankton do the Strangest Things”, that is targeted at 5-7 year olds and is designed to introduce them to the incredible diversity and fascinating adaptations of microscopic marine organisms. This research seeks to leverage 6 years (2015-2020) of 234Th samples collected on Palmer LTER program, 5 years of prior measurements (2009-2010, 2012-2014), and upcoming cruises (2021-2023) to develop a time-series of summertime particle flux in the WAP that stretches for 15 years. The 238U-234Th disequilibrium approach utilizes changes in the activity of the particle-active radio-isotope 234Th relative to its parent nuclide 238U to quantify the flux of sinking carbon out of the surface ocean (over a time-scale of ~one month). This proposal will fund 234Th analyses from nine years’ worth of cruises (2015-2023) and extensive analyses designed to investigate the processes driving inter-annual variability in the BCP. These include: 1) physical modeling to quantify the importance of advection and diffusion in the 234Th budget, 2) time-series analyses of particle flux, and 3) statistical modeling of the relationships between particle flux and multiple presumed drivers (biological, chemical, physical, and climate indices) measured by collaborators in the Palmer LTER program. This multi-faceted approach is critical for linking the measurements to models and for predicting responses to climate change. It will also test the hypothesis that export flux is decreasing in the northern WAP, increasing in the southern WAP, and increasing when integrated over the entire region as a result of earlier sea ice retreat and a larger ice-free zone. The project will also investigate relationships between carbon export and multiple potentially controlling factors including: primary productivity, algal biomass and taxonomic composition, biological oxygen saturation, zooplankton biomass and taxonomic composition, bacterial production, temperature, wintertime sea ice extent, date of sea ice retreat, and climate modes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Antarctic Automatic Weather Station (AWS) network is the most extensive ground meteorological network in the Antarctic, approaching its 30th year at several of its installations. Its prime focus as a long term observational record is to measure the near surface weather and climatology of the Antarctic atmosphere. AWS stations measure air-temperature, pressure, wind speed and direction at a nominal surface height of ~ 2-3m. Other parameters such as relative humidity and snow accumulation may also be taken. Observational data from the AWS are collected via Iridium network, or DCS Argos aboard either NOAA or MetOp polar orbiting satellites and thus made available in near real time to operational and synoptic weather forecasters. The surface observations from the AAWS network are important records for recent climate change and meteorological processes. The surface observations from the AAWS network are also used operationally, and in the planning of field work. The surface observations made from the AAWS network have been used to check on satellite and remote sensing observations. This project proposes to use the surface conditions observed by the AWS network to determine how large-scale modes of climate variability impact Antarctic weather and climate, how the surface observations from the AWS network are linked to surface layer and boundary layer processes, and to quantify the impact of snowfall and blowing snow events. Specifically, this project proposes to improve our understanding of the processes that lead to unusual weather events and how these events are related to large-scale modes of climate variability. This project will fill a gap in knowledge of snowfall distribution, and distinguishing between snowfall and blowing snow events using a suite of precipitation sensors near McMurdo Station.
Melt from the Greenland and Antarctic ice sheets is increasingly contributing to sea-level rise. This ice sheet mass loss is primarily driven by the thinning, retreat, and acceleration of glaciers in contact with the ocean. Observations from the field and satellites indicate that glaciers are sensitive to changes at the ice-ocean interface and that the increase in submarine melting is likely to be driven by the discharge of meltwater from underneath the glacier known as subglacial meltwater plumes. The melting of glacier ice also directly adds a large volume of freshwater into the ocean, potentially causing significant changes in the circulation of ocean waters that regulate global heat transport, making ice-ocean interactions an important potential factor in climate change and variability. The ability to predict, and hence adequately respond to, climate change and sea-level rise therefore depends on our knowledge of the small-scale processes occurring in the vicinity of subglacial meltwater plumes at the ice-ocean interface. Currently, understanding of the underlying physics is incomplete; for example, different models of glacier-ocean interaction could yield melting rates that vary over a factor of five for the same heat supply from the ocean. It is then very difficult to assess the reliability of predictive models. This project will use comprehensive laboratory experiments to study how the melt rates of glaciers in the vicinity of plumes are affected by the ice roughness, ice geometry, ocean turbulence, and ocean density stratification at the ice-ocean interface. These experiments will then be used to develop new and improved predictive models of ice-sheet melting by the ocean. This project builds bridges between modern experimental fluid mechanics and glaciology with the goal of leading to advances in both fields. As a part of this work, two graduate students will receive interdisciplinary training and each year two undergraduate students will be trained in experimental fluid mechanics to assist in this work and develop their own research projects. This project consists of a comprehensive experimental program designed for studying the melt rates of glacier ice under the combined influences of (1) turbulence occurring near and at the ice-ocean interface, (2) density stratification in the ambient water column, (3) irregularities in the bottom topology of an ice shelf, and (4) differing spatial distributions of multiple meltwater plumes. The objective of the experiments is to obtain high-resolution data of the velocity, density, and temperature near/at the ice-ocean interface, which will then be used to improve understanding of melt processes down to scales of millimeters, and to devise new, more robust numerical models of glacier evolution and sea-level rise. Specially, laser-based, optical techniques in experimental fluid mechanics (particle image velocity and laser-induced fluorescence) will be used to gather the data, and the experiments will be conducted using refractive-index matching techniques to eliminate changes in refractive indices that could otherwise bias the measurements. The experiments will be run inside a climate-controlled cold room to mimic field conditions (ocean temperature from 0-10 degrees C). The project will use 3D-printing to create different casting molds for making ice blocks with different types of roughness. The goal is to investigate how ice melt rate changes as a function of the properties of the plume, the ambient ocean water, and the geometric properties of the ice interface. Based on the experimental findings, this project will develop and test a new integral-plume-model coupled to a regional circulation model (MITgcm) that can be used to predict the effects of glacial melt on ocean circulation and sea-level rise. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John
No dataset link provided
Part I: Non-technical description: Water is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a new method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training of high-school curricular programming in Native American communities of the SouthWest. Part II: Technical description: Terrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from native American communities in the SouthWest where similar desert conditions exist. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project seeks to make detailed measurements of the oxygen content of the surface ocean along the Western Antarctic Peninsula. Detailed maps of changes in net oxygen content will be combined with measurements of the surface water chemistry and phytoplankton distributions. The project will determine the extent to which on-shore or offshore phytoplankton blooms along the peninsula are likely to lead to different amounts of carbon being exported to the deeper ocean. The project team members will participate in the development of new learning tools at the Museum of Life and Science. They will also teach secondary school students about aquatic biogeochemistry and climate, drawing directly from the active science supported by this grant. The project will analyze oxygen in relation to argon that will allow determination of the physical and biological contributions to surface ocean oxygen dynamics. These assessments will be combined with spatial and temporal distributions of nutrients (iron and macronutrients) and irradiances. This will allow the investigators to unravel the complex interplay between ice dynamics, iron and physical mixing dynamics as they relate to Net Community Production (NCP) in the region. NCP measurements will be normalized to Particulate Organic Carbon (POC) and be used to help identify area of "High Biomass and Low NCP" and those with "Low Biomass and High NCP" as a function of microbial plankton community composition. The team will use machine learning methods- including decision tree assemblages and genetic programming- to identify plankton groups key to facilitating biological carbon fluxes. Decomposing the oxygen signal along the West Antarctic Peninsula will also help elucidate biotic and abiotic drivers of the O2 saturation to further contextualize the growing inventory of oxygen measurements (e.g. by Argo floats) throughout the global oceans.
In contrast to the Arctic, sea ice cover in most Antarctic regions has increased since 1979. The area-integrated total sea ice extent grew to record maximum values in four of the last six years, yet the 2015-16 summer was marked by record low ice cover. While impressive, it is difficult to assess the significance of these very recent records in the context of longer term variability, since the continuous satellite record only dates back to 1978. The limited length of the continuous sea ice record, is a significant confounding factor in ascertaining whether the observed current changes are due to natural variability alone, or represent a forced anthropogenic response. As a result, the scientific understanding of the Antarctic sea ice trends remains poor, as does confidence in projections of future Antarctic sea ice trends. To address this challenge, this project seeks to reconstruct sea ice extent and sea ice concentration, using the relationships between satellite-observed sea ice, sea level pressure, tropical sea surface temperature, ENSO indices, some proxy data (ice cores, etc.), and in situ Southern Ocean temperature data. The aim of the study is to collect and combine these ancillary records as accurately as possible while retaining the variability associated with the intrinsic uncertainty in the available field data. A range of statistical methods for modelling the relationship between satellite era sea-ice data using flexible regression, Bayesian and multivariate dynamic spatial temporal (MDST) methods will be used. The study will entrain cross-disciplinary training of undergraduate and a graduate student at UCLA and Ohio University. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part I: Nontechnical description: This award represents a collaborative geoscience research effort between US NSF and UK Natural Environment Research Council (NERC) researchers with efforts in each nation funded by their respective countries (Dear Colleague Letter NSF 16-132). The research will focus on understanding the links between behavior, ecology, and evolution in a Southern Ocean wandering albatross population in response to global changes in climate and in exploitation of natural resources. The most immediate response of animals to global change typically is behavioral, and this work will provide a more comprehensive understanding of how differences individual bird behavior affect evolution and adaptation for the population under changing environments. Characterization of albatross personality, life-history traits, and population dynamics collected over long time scales will be used to develop robust forecasting of species persistence in the face of future global changes. The results of this project will feed into conservation and management decisions for endangered Southern Ocean species. The work will also be used to provide specific research training at all levels, including a postdoctoral scholar, graduate students and K-12 students. It will also support education for the public about impacts from human-induced activities on our polar ecosystems using animations, public lectures, printed and web media. Part II: Technical description Past research has shown that individual animal personalities range over a continuum of behavior, such that some individuals are consistently more aggressive, more explorative, and bolder than others. How the phenotypic distributions of personality and foraging behavior types within a population is created and maintained by ecological (demographic and phenotypic plasticity) and evolutionary (heritability) processes remain an open question. Differences in personality traits determine how individuals acquire resources and how they allocate these to reproduction and survival. Although some studies have found different foraging behaviors or breeding performances between personality types, none have established the link between personality differences in foraging behaviors and life histories (both reproduction and survival, and their covariations) in the context of global change. Furthermore, plasticity in foraging behaviors is not considered in the pace-of-life syndrome, which has potentially hampered our ability to find covariation between personality and life history trade-off. This project will fill these knowledge gaps and develop an eco-evolutionary model of the complex interactions among individual personality and foraging plasticity, heritability of personality and foraging behaviors, life history strategies, population dynamics in a changing environment (fisheries and climate) using a long-term database consisting of ~1,800 tagged wandering albatross seabirds (Diomedea exulans) with defined individual personalities and life history traits breeding in the Southern Ocean. Climate projections from IPCC atmospheric-oceanic global circulation models will be used to provide projections of population structure under future global change conditions. Specifically, the team will (1) characterize the differences in life history strategies along the shy-bold continuum of personalities and across environmental conditions; (2) develop the link between phenotypic plasticity in foraging effort and personality; (3) characterize the heritability of personality and foraging behaviors; (4) develop a stochastic eco-evolutionary model to predict population growth rates in a changing environment. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Antarctic Ice Sheet stability remains a large uncertainty in predicting future sea level. Presently, the greatest ice mass loss is observed in locations where relatively warm water comes into contact with glaciers and ice shelves, melting them from below. This has led researchers to hypothesize that the interactions that occur between the ocean and the ice are important for determining ice sheet stability and that increased warm water presence will accelerate Antarctic ice mass loss and lead to greater sea level rise in the coming century. To better predict future ice sheet behavior, it is critical to understand past ice-ocean interactions around Antarctica, especially during warm periods and at times when Earth’s climate was undergoing major changes. Past Antarctic ice mass and environmental conditions like ocean temperature can be reconstructed using sediments, which capture an environmental record as they accumulate on the ocean floor. By looking at sediment composition and by analyzing geochemical signatures within the sediment, it is possible to piece together a record of climate change on hundred- to million-year timescales. This project will reconstruct upper ocean temperatures and Antarctic ice retreat/advance cycles from 2.6 to 0.7 million years ago, which encompasses the Mid-Pleistocene Transition, a time in Earth’s history that marks the shift from 41-thousand year glacial cycles to 100-thousand year glacial cycles. A record will be generated from existing sediment cores collected from the Scotia Sea during International Ocean Discovery Program Expedition 382. The Mid-Pleistocene Transition (MPT; ~1.25–0.7 Ma) marks the shift from glacial-interglacial cycles paced by obliquity (~41 kyr cycles) to those paced by eccentricity (~100-kyr cycles). This transition occurred despite little variation in Earth’s orbital parameters, suggesting a role for internal climate feedbacks. The MPT was accompanied by decreasing atmospheric pCO2, increasing deep ocean carbon storage, and changes in deep water formation and distribution, all of which are linked to Antarctic margin atmosphere-ice-ocean interactions. However, Pleistocene records that document such interactions are rarely preserved on the shelf due to repeated Antarctic Ice Sheet (AIS) advance; instead, they are preserved in deep Southern Ocean basins. This project takes advantage of the excellent preservation and recovery of continuous Pleistocene sediment sequences collected from the Scotia Sea during International Ocean Discovery Program Expedition 382 to test the following hypotheses: 1) Southern Ocean upper ocean temperatures vary on orbital timescales during the early to middle Pleistocene (2.6–0.7 Ma), and 2) Southern Ocean temperatures co-vary with AIS advance/retreat cycles. Paleotemperatures will be reconstructed using the TetraEther indeX of 86 carbons (TEX86), a proxy that utilizes marine archaeal biomarkers. The Scotia Sea TEX86-based paleotemperature record will be compared to records of AIS variability, including ice rafted debris. Expedition 382 records will be compared to orbitally paced climatic time series and the benthic oxygen isotope record of global ice volume and bottom water temperature to determine if a correlation exists between upper ocean temperature, AIS retreat/advance, and orbital climate forcing. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The spatial extent of the West Antarctic Ice Sheet during the last interglacial period (129,000 to 116,000 years ago) is currently unknown, yet this information is fundamental to projections of the future stability of the ice sheet in a warming climate. Paleoclimate records and proxy evidence such as dust can inform on past environmental conditions and ice-sheet coverage. This project will combine new, high-sensitivity geochemical measurements of dust from Antarctic ice collected at Allan Hills with existing water isotope records to document climate and environmental changes through the last interglacial period. These changes will then be compared with Earth-system model simulations of dust and water isotopes to determine past conditions and constrain the sensitivity of the West Antarctic Ice Sheet to warming. The project will test the hypothesis that the uncharacteristically volcanic dust composition observed at another peripheral ice core site at Taylor Glacier during the last interglacial period is related to changes in the spatial extent of the West Antarctic Ice Sheet. This project aims to characterize mineral dust transport during the penultimate glacial-interglacial transition. The team will apply high-precision geochemical techniques to the high-volume, high-resolution ice core drilled at the Allan Hills site in combination with Earth system model simulations to: (1) determine if the volcanic dust signature found in interglacial ice from Taylor Glacier is also found at Allan Hills, (2) determine the likely dust source(s) to this site during the last interglacial, and (3) probe the atmospheric and environmental changes during the last interglacial with a diminished West Antarctic Ice Sheet. The team will develop a suite of measurements on previously drilled ice from Allan Hills, including isotopic compositions of Strontium and Neodymium, trace element concentrations, dust-size distribution, and imaging of ice-core dust to confirm the original signal observed and provide a broader spatial reconstruction of dust transport. In tandem, the team will conduct Earth system modeling with prognostic dust and water-isotope capability to test the sensitivity of dust transport under several plausible ice-sheet and freshwater-flux configurations. By comparing dust reconstruction and model simulations, the team aims to elucidate the driving mechanisms behind dust transport during the last interglacial period. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Ice shelves play a critical role in restricting the seaward flow of grounded glacier ice by providing buttressing at their bases and sides. Processes that affect the long-term stability of ice shelves can therefore influence the future contribution of the Antarctic Ice Sheet to global sea-level rise. The Ross Ice Shelf is the largest ice shelf on Earth, and it buttresses massive areas of West and East Antarctica. Previous studies of modern ice velocity indicated that the Ross Ice Shelf’s mass loss is roughly balanced by its mass gain. However, more recent work that extends further back in time reveals the ice shelf is likely not in steady state, with possible long-term thinning since the late 1990s. Consequently, to accurately interpret modern-day ice-shelf changes, long-term observations are critical to evaluate how these recent variations fit into the historical context of ice-shelf variability. This project will examine more than four decades of historical and modern airborne radar sounding observations of the Ross Ice Shelf (spanning 1971 to 2017) to investigate ice-shelf changes on decadal timescales. The team will process, calibrate, and analyze radar data collected during 1971-79 field campaigns and compare them against modern observations collected between 2011-17. They will estimate basal melt rates by examining changes in ice-shelf thickness, and will determine other important metrics for melt, including ice-shelf roughness, englacial temperature, and marine-ice formation. The project will support the education of a Ph.D. student at each of the three participating institutions. In addition, the project will support the training of undergraduate and high-school researchers in radioglaciology and Antarctic sciences. The project will test the hypothesis that, over decadal timescales, the basal melt rates beneath the Ross Ice Shelf have been low, particularly under shallow ice drafts, leading to overall thickening and increased buttressing potential. The team aims to provide a direct estimate of basal melt rates based on changes in ice-shelf thickness that occurred between 1971 and 2017. This project will extend similar work completed at Thwaites Glacier and improve the calibration methods on the vertical scaling for fast-time and depth conversion. The work will also leverage the dense modern surveys to improve the geolocation of radar film collected on earlier field campaigns to produce a more precise comparison of local shelf thickness with the modern data. In addition, the team will conduct englacial attenuation analysis to calculate englacial temperature to infer the trends in local basal melting. They will also examine the radiometric and scatterometric character of bed echoes at the ice-ocean boundary to characterize changes in ice-shelf basal roughness, marine-ice formation related to local basal freezing, and structural damage from fracture processes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The potential for future sea level rise from melting and collapse of Antarctic ice sheets and glaciers is concerning. We can improve our understanding of how water is exchanged between Antarctic ice sheets and the ocean by studying how ice sheets behaved in past climates, especially conditions that were similar to or warmer than those at present. For this project, the research team will document Antarctica’s response across an interval when Earth transitioned from the warm Pliocene into the Pleistocene ice ages by combining marine and land evidence for glacier variations from sites near the Antarctic Peninsula, complimented by detailed work on timescales and fossil evidence for environmental change. An important goal is to test whether Antarctica’s glaciers changed at the same time as glaciers in the Northern Hemisphere as Earth's most recent Ice Age intensified, or alternatively responded to regional climate forcing in the Southern Hemisphere. Eleven investigators from seven US institutions, as well as Argentine collaborators, will study new sediment cores from the International Ocean Discovery Program, as well as legacy cores from that program and on-land outcrops on James Ross Island. The group embraces a vertically integrated research program that allows high school, undergraduate, graduate, post-docs and faculty to work together on the same projects. This structure leverages the benefits of near-peer mentoring and the development of a robust collaborative research network while allowing all participants to take ownership of different parts of the project. All members of the team are firmly committed to attracting researchers from under-represented groups and will do this through existing channels as well as via co-creating programming that centers the perspectives of diverse students in conversations about sea-level rise and climate change. The proposed research seeks to understand phasing between Northern and Southern Hemisphere glacier and climate changes, as a means to understand drivers and teleconnections. The dynamics of past Antarctic glaciation can be studied using the unique isotope geochemical and mineralogic fingerprints from glacial sectors tied to a well-constrained time model for the stratigraphic successions. The proposed work would further refine the stratigraphic context through coupled biostratigraphic and magnetostratigraphic work. The magnitude of iceberg calving and paths of icebergs will be revealed using the flux, geochemical and mineralogic signatures, and 40Ar/39Ar and U-Pb geochronology of ice-rafted detritus. These provenance tracers will establish which sectors of Antarctica’s ice sheets are more vulnerable to collapse, and the timing and pacing of these events will be revealed by their stratigraphic context. Additionally, the team will work with Argentine collaborators to connect the marine and terrestrial records by studying glacier records intercalated with volcanic flows on James Ross Island. These new constraints will be integrated with a state of the art ice-sheet model to link changes in ice dynamics with their underlying causes. Together, these tight stratigraphic constraints, geochemical signatures, and ice-sheet model simulations will provide a means to compare to the global records of climate change, understand their primary drivers, and elucidate the role of the Antarctic ice sheet in a major, global climatic shift from the Pliocene into the Pleistocene. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Schmittner, Andreas; Haight, Andrew ; Clark, Peter
No dataset link provided
This project investigates Antarctic ice-ocean interactions of the last 20,000 years. The Antarctic ice sheet is an important component of Earth’s climate system, as it interacts with the atmosphere, the surrounding Southern Ocean, and the underlaying solid Earth. The ice sheet is also the largest potential contributor to future sea-level rise and a major uncertainty in climate projections. Climate change may trigger instabilities that may lead to fast and irreversible collapse of parts of the ice sheet. However, little is known about how interactions between the Antarctic ice sheet and the rest of the climate system affect its behavior, climate, and sea level, partly because most climate models currently do not have fully-interactive ice-sheet components. The project team will construct a numerical climate model that includes an interactive Antarctic ice sheet, improving computational infrastructure for research. The model code will be made freely available to the public on a code-sharing site. In addition, the team will synthesize paleoclimate data and compare these with model simulations. This model-data comparison will test three scientific hypotheses regarding past changes in deep-ocean circulation, ice sheet, carbon, and sea level. The project will contribute to a better understanding of ice-ocean interactions and past climate variability. The project will test ideas that ice-ocean interactions have been important for setting deep ocean circulation and carbon storage during the Last Glacial Maximum and subsequent deglaciation. The new model will consist of three existing and well-tested components: (1) an isotope-enabled climate-carbon cycle model of intermediate complexity; (2) a model of the combined Antarctic ice sheet, solid Earth, and sea level; and (3) an iceberg model. The coupling will include ocean-temperature effects on basal melting of ice shelves; freshwater fluxes from the ice sheet to the ocean; and calving, transport and melting of icebergs. Once constructed and optimized, the model will be applied to simulate the Last Glacial Maximum and subsequent deglaciation. Differences between model versions with full, partial, or no coupling will be used to investigate the effects of ice-ocean interactions on the Meridional Overturning Circulation, deep ocean carbon storage, and ice-sheet fluctuations. Paleoclimate data synthesis will include temperature, carbon and nitrogen isotopes, radiocarbon ages, protactinium-thorium ratios, neodymium isotopes, carbonate ion, dissolved oxygen, relative sea level, and terrestrial cosmogenic ages into one multi-proxy database with a consistent updated chronology. The project will support an early-career scientist, one graduate student, undergraduate students, and new and ongoing national and international collaborations. Outreach activities in collaboration with a local science museum will benefit rural communities in Oregon by improving their climate literacy. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Bubbles of ancient air trapped in ice cores have been used to directly reconstruct atmospheric composition, and its links to Antarctic and global climate, over the last 800,000 years. Previous field expeditions to the Allan Hills Blue Ice Area, Antarctica, have recovered ice cores that extend as far back as 2.7 million years, by far the oldest polar ice samples yet recovered. These ice cores extend direct observations of atmospheric carbon dioxide and methane concentrations and indirect records of Antarctic climate into a period of Earth's climate history that represents a plausible geologic analogue to future anthropogenic climate change. The results demonstrate a smaller glacial-interglacial variability of climate and greenhouse gases, and a persistent linkage between Antarctic climate and atmospheric carbon dioxide, between 1 and 2 million years ago. Through this project, the team will return to the Allan Hills Blue Ice Area to recover additional ice cores that date to 2 million years or older. The climate records developed from these ice cores will provide new insights into the chemical composition of the atmosphere and Antarctic climate during times of comparable or even greater warmth than the present day. Project results will help answer questions about issues associated with anthropogenic change including the relationship between temperature change and the mass balance of Antarctic ice and the relationship between atmospheric greenhouse gases and global climate change. Earth has been cooling, and ice sheets expanding, over the past ~52 million years. Superimposed on this cooling are periodic changes in Earth's climate system driven by variations in the eccentricity, precession, and obliquity of Earth's orbit around the Sun. Climate reconstructions based on measurements of oxygen isotopes in foraminiferal calcite indicate that, from ~2.8 to 1.2 million years before present (Ma), Earth's climate system oscillated between glacial and interglacial states every ~40,000 years (the "40k world"). Between 1.2-0.8 Ma and continuing to the present, the period of glacial cycles increased in amplitude and lengthened to ~100,000 years (the "100k world"). Ice cores preserve ancient air that allows direct reconstructions of atmospheric carbon dioxide and methane. They also archive proxy records of regional climate, mean ocean temperature, global oxygen cycling, and the aridity of nearby continents. Studies of stratigraphically continuous ice cores, extending to 800,000 years before present, have demonstrated that atmospheric carbon dioxide is strongly linked to climate, and it is of great interest to extend the ice-core record into the 40k world. Recent discoveries of well-preserved ice dating from 1.0 to 2.7 Ma from ice cores drilled in the Allan Hills Blue Ice Area (BIA), Antarctica, demonstrate the potential to retrieve stratigraphically discontinuous old ice at shallow depths (<200 meters). This project will continue this work by retrieving new large-volume ice cores and measuring paleoclimate properties in both new and existing ice from the Allan Hills BIA. The experimental objectives are to more fully characterize fundamental properties of the climate system and the carbon cycle during the 40k world. Project results will have implications for Pleistocene climate change, and will provide new constraints on the processes that regulate atmospheric carbon dioxide, methane, and oxygen on geologic timescales. Given a demonstrated age of the ice at the Allan Hills BIA of at least 2 million years, the team will drill additional cores to prospect for ice that predates the initiation of Northern Hemisphere glaciation at the Plio-Pleistocene transition (~2.8 Ma). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The West Antarctic Ice Sheet is the most vulnerable polar ice mass to warming and already a major contributor to global mean sea level rise. Its fate in the light of prolonged warming is a topic of major uncertainty. Accelerated sea level rise from ice mass loss in the polar regions is a major concern as a cause of increased coastal flooding affecting millions of people. This project will disclose a unique geological archive buried beneath the seafloor off the Amundsen Sea, Antarctica, which will reveal how the West Antarctic Ice Sheet behaved in a warmer climate in the past. The data and insights can be used to inform ice-sheet and ocean modeling used in coastal policy development. The project will also support the development of a competitive U.S. STEM workforce. Online class exercises for introductory geology classes will provide a gateway for qualified students into undergraduate research programs and this project will enhance the participation of women in science by funding the education of current female Ph.D. students. The project targets the long-term variability of the West Antarctic Ice Sheet over several glacial-interglacial cycles in the early Pliocene sedimentary record drilled by the International Ocean Discovery Program (IODP) Expedition 379 in the Amundsen Sea. Data collection includes 1) the sand provenance of ice-rafted debris and shelf diamictites and its sources within the Amundsen Sea and Antarctic Peninsula region; 2) sedimentary structures and sortable silt calculations from particle size records and reconstructions of current intensities and interactions; and 3) the bulk provenance of continental rise sediments compared to existing data from the Amundsen Sea shelf with investigations into downslope currents as pathways for Antarctic Bottom Water formation. The results are analyzed within a cyclostratigraphic framework of reflectance spectroscopy and colorimetry (RSC) and X-ray fluorescence scanner (XRF) data to gain insight into orbital forcing of the high-latitude processes. The early Pliocene Climatic Optimum (PCO) ~4.5-4.1 Ma spans a major warm period recognized in deep-sea stable isotope and sea-surface temperature records. This period also coincides with a global mean sea level highstand of > 20 m requiring contributions in ice mass loss from Antarctica. The following hypotheses will be tested: 1) that the West Antarctic Ice Sheet retreated from the continental shelf break through an increase in sub iceshelf melt and iceberg calving at the onset of the PCO ~4.5 Ma, and 2) that dense shelf water cascaded down through slope channels after ~4.5 Ma as the continental shelf became exposed during glacial terminations. The project will reveal for the first time how the West Antarctic Ice Sheet operated in a warmer climate state prior to the onset of the current “icehouse” period ~3.3 Ma. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part I: Non-technical summary: The Amundsen Sea is adjacent to the West Antarctic Ice Sheet (WAIS) and hosts the most productive coastal ecosystem in all of Antarctica, with vibrant green waters visible from space and an atmospheric carbon dioxide uptake rate ten times higher than the Southern Ocean average. The region is also an area highly impacted by climate change and glacier ice loss. Upwelling of warm deep water is causing melt under the ice sheet, which is contributing to sea level rise and added nutrient inputs to the region. This is a project that is jointly funded by the National Science Foundation’s Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award, each Agency funds the proportion of the budget and the investigators associated with its own country. In this collaboration, the US team will undertake biogeochemical sampling alongside a UK-funded physical oceanographic program to evaluate the contribution of micronutrients such as iron from glacial meltwater to ecosystem productivity and carbon cycling. Measurements will be incorporated into computer simulations to examine ecosystem responses to further glacial melting. Results will help predict future impacts on the region and determine whether the climate sensitivity of the Amundsen Sea ecosystem represents the front line of processes generalizable to the greater Antarctic. This study is aligned with the large International Thwaites Glacier Collaboration (ITGC) and will make data available to the full scientific community. The program will provide training for undergraduate, graduate, post-doctoral, and early-career scientists in both science and communication. The team will also develop out-of-school science experiences for middle and high schoolers related to climate change and Antarctica. Part II: Technical summary: The Amundsen Sea hosts the most productive polynya in all of Antarctica, with atmospheric carbon dioxide uptake rates ten times higher than the Southern Ocean average. The region is vulnerable to climate change, experiencing rapid losses in sea ice, a changing icescape and some of the fastest melting glaciers flowing from the West Antarctic Ice Sheet, a process being studied by the International Thwaites Glacier Collaboration. The biogeochemical composition of the outflow from the glaciers surrounding the Amundsen Sea is largely unstudied. In collaboration with a UK-funded physical oceanographic program, ARTEMIS is using shipboard sampling for trace metals, carbonate system, nutrients, organic matter, and microorganisms, with biogeochemical sensors on autonomous vehicles to gather data needed to understand the impact of the melting ice sheet on both the coastal ecosystem and the regional carbon cycle. These measurements, along with access to the advanced physical oceanographic measurements will allow this team to 1) bridge the gap between biogeochemistry and physics by adding estimates of fluxes and transport of limiting micronutrients; 2) provide biogeochemical context to broaden understanding of the global significance of ocean-ice shelf interactions; 3) determine processes and scales of variability in micronutrient supply that drive the ten-fold increase in carbon dioxide uptake, and 4) identify small-scale processes key to iron and carbon cycling using optimized field sampling. Observations will be integrated into an ocean model to enhance predictive capabilities of regional ocean function. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Blue and fin whales are the two largest animals on the planet, and the two largest krill predators in the Southern Ocean. Commercial whaling in Antarctic waters started in the early 1900?s, and by the 1970's whale populations were reduced from thousands to only a few hundred individuals. The absence of data about whale biology and ecology prior to these large population reductions has limited our understanding of how the ecosystem functioned when cetacean populations were more robust. However, an archive of baleen plates from 800 Antarctic blue and fin whales harvested between 1946 and 1948 was recently rediscovered in the Smithsonian's National Museum of Natural History that will shed insight into historic whale ecology. As baleen grows, it incorporates circulating hormones, and compounds from the whale's diet, recording continuous biological and oceanographic information across multiple years. This project will apply a suite of modern molecular techniques to these archived specimens to ask how blue and fin whale foraging and reproduction responded to climate variability, changes at the base of the food web, and whaling activities in the early 1940s. By comparison with more modern datasets, these investigations will fill major gaps in understanding of the largest krill predators, their response to disturbance and environmental change, and the impact that commercial whaling has had on the structure and function of the Antarctic marine ecosystem. This project will improve stem education through annual programming for middle and high school girls in partnership with UNCW's Marine Quest program. Public outreach will occur through partnerships with the Smithsonian and the International Association of Antarctic Tour Operators to deliver emerging research on Antarctic ecosystems and highlight the contemporary relevance and scientific value of museum collections. Examination of past conditions and adaptations of polar biota is fundamental to predictions of future climate change scenarios. The baleen record that will be used in this study forms an ideal experimental platform for studying bottom-up, top-down and anthropogenic impacts on blue and fin whales. This historic baleen archive includes years with strong climate and temperature anomalies allowing the influence of climate variability on predators and the ecosystems that support them to be examined. Additionally, the impact of commercial whaling on whale stress levels will be investigated by comparing years of intensive whaling with the non-whaling years of WWII, both of which are captured in the time series. There are three main approaches to this project. First, bulk stable isotope analysis will be used to examine the trophic dynamics of Antarctic blue and fin whales. Second, compound-specific stable isotope analyses (CSIA-AA) will characterize the biogeochemistry of the base of the Antarctic food web. Finally, analyses of hormone levels in baleen will reveal differences in stress levels and reproductive status of individuals, and inform understanding of cetacean population biology. This project will generate a new public data archive to foster research opportunities across various components of the OPP program, all free from the logistical constraints of Antarctic field work. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The Antarctic Ice Sheet (AIS) is sensitive to and an indicator of climate change. While ice loss is largely driven by ocean warming, this might be mitigated by enhanced snowfall on the ice sheet. By developing an understanding of the processes governing snowfall variability and change on the AIS, this project will contribute to understanding the long-term role of the AIS as a contributor to sea-level rise. This project is strongly embedded in the collaborative, open-source framework of the Community Earth System Model version 2 (CESM2) and will deliver new datasets of Antarctic precipitation for use by the research community. The project will help to build a diverse geoscience workforce by recruiting and training a student to be directly involved in the research through the Significant Opportunities in Atmospheric Research and Science (SOARS) program. The project will leverage the Climate Model Intercomparison Project 6 climate model ensemble as a whole, and CESM2 in particular, to disentangle the major sources of uncertainty and to elucidate the underlying mechanisms of Antarctic precipitation change, with a particular focus on the role of atmospheric circulation changes relative to the role of atmospheric warming. Using the variable resolution capabilities of CESM2, the team will provide the community with precipitation estimates at a very high horizontal resolution. The analyses will also use a forthcoming 100-member large ensemble. The project seeks to answer the following questions: 1) How well does the CESM2 represent the present-day Antarctic surface climate, precipitation, and surface mass balance, including the mean and its variability? 2) What is the sensitivity of simulated Antarctic precipitation to model resolution in present-day and future climates? 3) What are the roles of thermodynamics (warming atmosphere and ocean) and dynamics (changes in atmospheric circulation) in observed and projected snowfall changes? How do these break down into forced and internal variability? In particular, is there a significant forced precipitation trend due to circulation changes driven by stratospheric ozone depletion and recovery and increases in greenhouse gas concentration? 4) What processes and boundary conditions drive the ensemble spread of Antarctic precipitation in single-model and multi-model ensembles? How does the spread driven by initial surface conditions (including sea ice cover, surface fluxes, inversion strength) compare with the irreducible uncertainty due to internal climate system variability? This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part I: Non-technical Summary Understanding the mechanisms that animals use to find and acquire food is a fundamental question in ecology. The survival and success of marine predators depends on their ability to locate prey in a variable or changing environment. To do this the predators need to be able to adjust foraging behavior depending on the conditions they encounter. Emperor penguins are ice-dependent, top predators in Antarctica. However, they are vulnerable to environmental changes that alter food web or sea ice coverage, and environmental change may lead to changes in penguin foraging behavior, and ultimately survival and reproduction success. Despite their importance in the Southern Ocean ecosystem, relatively little is known about the specific mechanisms Emperor penguins use to find and acquire food. This study combines a suite of technological and analytical tools to gain essential knowledge on Ross Sea penguin foraging energetics, ecology, and habitat use during critical periods in their life history, especially during late chick-rearing periods. Energy management is particularly crucial during this time as parents need to feed both themselves and their rapidly growing offspring, while being constrained to regions near the colony. Penguin ecology and habitat preference will also be evaluated after the molt and through early reproduction. This study fills important ecological knowledge gaps on the energy balance, diet, and habitat use by penguins during these critical periods. Finally, the project furthers the NSF goals of training new generations of scientists through training of undergraduates, graduate students and a postdoctoral researcher. Public outreach activities will be aligned with another NSF funded project designed to provide science training in afterschool and camp programs that target underrepresented groups. Part II: Technical summary This project will identify behavioral and physiological variability in foraging Emperor penguins that can be directly linked to individual success in the marine environment using an ecological theoretical framework during two critical life history stages. First, this project will investigate the foraging energetics, ecology, and habitat use of Emperor penguins at Cape Crozier using fine-scale movement and video data loggers during the energetically demanding life history phase of late chick-rearing. Specifically, this study will 1) Estimate the relationship of foraging efficiency to foraging behavior and diet using an optimal foraging theory framework to identify what environmental or physiological constraints influence foraging behavior; 2) Investigate the inter- and intra-individual behavioral variability exhibited by emperor penguins, which is essential to predict how resilient these penguins are to environmental change; and 3) Integrate penguin foraging efficiency data with environmental data to identify important habitat. Next the researchers will study the ecology and habitat preference after the molt and through early reproduction using satellite-linked data loggers. The team will: 1) Investigate penguin inter- and intra-individual behavioral variability during the three-month post-molt and early winter foraging trips; and 2) Integrate penguin behavioral data with environmental data to identify which environmental features are indicative of habitat preference when penguins are not constrained to returning to the colony to feed a chick. These fine- and coarse-scale data will be combined with climate predictions to create predictive habitat models. The education objectives of this CAREER project are designed to inspire, engage, and train the next generation of scientists using the data and video generated while investigating Emperor penguins in the Antarctic ecosystem. This includes development of two university courses, training of undergraduate and graduate students, and a collaboration with the NSF funded “Polar Literacy: A model for youth engagement and learning” program to develop after school and camp curriculum that target undeserved and underrepresented groups. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The emperor penguin is an iconic seabird that is found in colonies distributed around the entirety of the Antarctic coastline. Emperor penguins are an important indicator species for the health of the Southern Ocean because their reliance on sea ice for major parts of their life cycle means that their population can be influenced by changes in the extent and duration of sea ice around Antarctica. Although baseline data exists on emperor penguin distributions and overall population size, data on how population size varies at individual colonies is limited to only a few locations. Thus, knowledge about how changes in local or regional environmental conditions impacts local or global population status is poorly understood. By combining established methods in satellite remote sensing with ground and aerial surveys of several colonies across the continent, this project will generate population estimates for the 54 known emperor penguin colonies. Decadal scale population trend data will be combined with environmental variables (e.g., sea ice extent and duration among others) to reveal which conditions influence population fluctuations at regional and continental scales. The project will engage with international collaborators, train post-doctoral associates and future scientists, and develop citizen science and K-12 outreach programs. This project on emperor penguin populations will quantify penguin presence/absence, and colony size and trajectory, across the entire Antarctic continent using high-resolution satellite imagery. For a subset of the colonies, population estimates derived from high-resolution satellite images will be compared with those determined by aerial surveys. This validated information will be used to determine population estimates for all emperor penguin colonies through iterations of supervised classification and maximum likelihood calculations on the high-resolution imagery. The effect of spatial, geophysical, and environmental variables on population size and decadal-scale trends will be assessed using generalized linear models. This research will result in a first ever empirical result for emperor penguin population trends and habitat suitability, and will leverage currently-funded NSF infrastructure and hosting sites to publish results in near-real time to the public. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Part I: Non-technical description: Predicting how polar ice sheets will respond to future global warming is difficult because all the processes that contribute to their melting are not well understood. This is important because the more ice on land that melts, the higher sea levels will rise. The most significant uncertainty in current estimates of sea-level rise in the coming decades is the potential contribution from the Antarctic Ice Sheet. One way to increase our knowledge about how large ice sheets respond to climate change in response to natural factors is to examine the geologic past. Natural global warming (and cooling) events in Earth’s history provide examples that we can use to better understand processes, interactions, and responses we can’t directly observe today. One such time period, approximately three million years ago (known as the Pliocene), was the last time atmospheric carbon dioxide levels were as high as they are today and, therefore, represents a time period to study to better understand the ice sheet response to a warming climate. Specifically, this project is interested in understanding how ocean currents near Antarctica, which transport heat and store carbon, behaved during these past climate events. The history of past ice sheet-ocean interactions are recorded in sediments that were deposited, layer upon layer, in the deep sea offshore Antarctica. In January-February 2018, a team of scientists and crew set sail to the Ross Sea, offshore west Antarctica, on the scientific ocean drilling vessel JOIDES Resolution to recover such sediment archives. This project focuses on a sediment core from that expedition, which captures the relatively warm Pliocene time interval, as well as the subsequent transition into cooler climates typical of the past two million years. The researchers will analyze the sediment with multiple complementary measurements, including: grain size, composition, chemistry of organic matter, physical structures, microfossil type and abundance, and more. These analyses will be done by the research team, including several students, at their respective laboratories and will then integrated into a unified record of ice sheet-ocean interactions. Ultimately, the results will be used to improve modeled projections of how the Antarctic Ice Sheet could respond to future climate change. Part II: Technical description: Geological records from the Antarctic Ice Sheet (AIS) margin demonstrate that the ice sheet oscillated in response to orbital variations in insolation (i.e., ~400, 100, 41, and 20 kyr), and it appears to be more sensitive to specific frequencies that regulate mean annual insolation (i.e., 41-kyr obliquity), particularly when the ice sheet extends into marine environments and is impacted by ocean circulation. However, the relationship between orbital forcing and the production of Antarctic Bottom Water (AABW) is unconstrained. Thus, a knowledge gap exists in understanding how changing insolation impacts ice marginal and Southern Ocean conditions that directly influence ventilation of the global ocean. The researchers hypothesize that insolation-driven changes directly affected the production and export of AABW to the Southern Ocean from the Pliocene through the Pleistocene. For example, obliquity amplification during the warmer Pliocene may have led to enhanced production and export of dense waters from the shelf due to reduced AIS extent, which, in turn, led to greater AABW outflow. To determine the relationship of AABW production to orbital regime, they plan to reconstruct both from a single, continuous record from the levee of Hillary Canyon, a major conduit of AABW outflow, on the Ross Sea continental rise. To test their hypothesis, they will analyze sediment from IODP Site U1524 (recovered in 2018 during International Ocean Discovery Program Expedition 374) and focus on three data sets. (1) They will use the occurrence, frequency, and character of mm-scale turbidite beds as a proxy of dense-shelf-water cascading outflow and AABW production. They will estimate the down-slope flux via numerical modeling of turbidity current properties using morphology, grain size, and bed thickness as input parameters. (2) They will use grain-size data, physical properties, XRF core scanning, CT imaging, and hyperspectral imaging to guide lithofacies analysis to infer processes occurring during glacial, deglacial, and interglacial periods. Statistical techniques and optimization methods will be applied to test for astronomical forcing of sedimentary packages in order to provide a cyclostratigraphic framework and interpret the orbital-forcing regime. (3) They will use bulk sedimentary carbon and nitrogen abundance and isotope data to determine how relative contributions of terrigenous and marine organic matter change in response to orbital forcing. All of these data will be integrated with sedimentological records to deconvolve organic matter production from its deposition or remobilization due to AABW outflow as a function of the oscillating extent of the AIS. These data sets will be integrated into a unified chronostratigraphy to determine the relationship between AABW outflow and orbital-forcing scenarios under the varying climate regimes of the Plio-Pleistocene. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Despite several decades of successful Antarctic aviation, centered upon flight operations in the McMurdo (Phoenix Field, Ross Island; RsI) area, systemized description of radar observations such as are normally found essential in operational aviation settings are notably lacking. The Ross Island region of Antarctica is a topographically complex region that results in large variations in the mesoscale high wind and precipitation features across the region. The goals of this project are to increase the understanding of the three-dimensional structure of these mesoscale meteorology features. Of particular interest are those features observed with radar signals. This project will leverage observations from the scanning X-band radar installed during the AWARE field campaign in 2016 and the installation of an EWR Radar Systems X-band scanning radar (E700XD) to be deployed during the 2019-20 field season, at McMurdo. Several science questions and case studies will be addressed during the season. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Uncertainty in projections of future sea level rise comes, in part, from ice-sheet melting under the influence of unpredictable variations in ocean and atmospheric temperature near ice sheets. Using state-of-the-art modeling techniques, the Antarctic Ice Sheet Large Ensemble (AISLENS) Project will estimate the range of possible Antarctic Ice Sheet melt during the recent past and over the next several centuries that could result from such climate variations. The AISLENS Project will also facilitate research by providing modeling output as an open product to the broader climate and glaciology communities. The project will support an early career faculty member, and interdisciplinary training for a graduate student, postdoctoral fellow and undergraduate student. As a part of this project, an undergraduate course on "Sea Level Rise and Coastal Engineering" will be also developed, bringing together Earth Science and Civil Engineering students in an interdisciplinary setting and contributing to their education in sea level science and coastal adaptation. This will be done in the geographic context of the Southeastern US, the region of most concentrated vulnerability to sea-level rise in the US. The primary goal of the proposed research is to understand and quantify the role of internal climate variability in driving ice loss from the Antarctic Ice Sheet over the recent past and into the future. The AISLENS Project will encompass hundreds of simulations of Antarctic ice sheet evolution from 1950 to 2300 forced by realistic variations in climate, including snowfall and melt from fluctuating oceanic and atmospheric temperatures. Plausible realizations of Antarctic climate forcing will be generated from stochastic emulation of output from the Energy Exascale Earth System Model (E3SM) under past and future emissions scenarios. These realizations of variable climate will be used to force the MPAS Albany Land Ice (MALI) model, a state-of-the-art model of ice flow in the Antarctic Ice Sheet. In this project, AISLENS will be used to conduct uncertainty and attribution analyses. In the uncertainty analysis, the evolution of ensemble spread in simulations of the future evolution of the Antarctic Ice Sheet will be systematically decomposed to determine which temporal and spatial scales of climate variability contribute the most to future ice-sheet projection uncertainty. In the attribution analysis, a range of satellite-based observations of recent Antarctic ice loss will be compared to the envelope of internal variability of Antarctic ice loss simulated in AISLENS simulations encompassing the recent past. This analysis will provide context to recent observations indicating significant variability of Antarctic climate forcing and provide a possible path forward for conducting robust statistical inference studies for observed ice-sheet changes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Enderlin/1643455 This award supports a project that will use a novel remote sensing method, which was initially developed to investigate melting of icebergs around Greenland, to examine spatial and temporal variations in ocean forcing around the Antarctic ice sheet periphery. Nearly three-quarters of the Antarctic ice sheet is fringed by regions of floating glacier ice called ice shelves. These ice shelves play an important role in modulating the flow of ice from the ice sheet interior towards the coast, similar to how dams regulate the downstream flow of water from reservoirs. Therefore, a reduction in ice shelf size due to changing air and ocean temperatures can have serious implications for the flux of glacier ice reaching the Antarctic coast, and thus, sea level change. Observations of recent ocean warming in the Amundsen Sea, thinning of the ice shelves, and increased ice flux from the West Antarctic ice sheet interior suggests that ice shelf destabilization triggered by ocean warming may already be underway in some regions. Although detailed observations are available in the Amundsen Sea region, our understanding of spatial and temporal variations in ocean conditions and their influence on ice shelf stability is limited by the scarceness of observations spanning the ice sheet periphery. The project will yield insights into variability in the submarine melting of ice shelves and will help advance the career of a female early-career scientist in a male-dominated field. The project will use repeat, very high-resolution (~0.5 m pixel width and length) satellite images acquired by the WorldView satellites, to estimate rates of iceberg melting in key coastal regions around Antarctica. The satellite images will be used to construct maps of iceberg surface elevation, which will be differenced in time to derive time series of iceberg volume change and area-averaged melt rates. Where ocean data are available, the melt rates will be compared to these data to assess whether variations in ocean temperature can explain observed iceberg melt variability. Large spatial gradients in melt rates will be compared to estimates of iceberg drift rates, which will be inferred from the repeat satellite images as well as numerically modeled drift rates produced by (unfunded) collaborators, to quantify the effects of water shear on iceberg melt rates. Spatial and temporal patterns in iceberg melting will also be compared to independently derived ice shelf thickness datasets. Overall, the analysis should yield insights into the effects of changes in ocean forcing on the submarine melting of Antarctic ice shelves and icebergs. The project does not require field work in Antarctica.
Overview and Intellectual merit: This project extends and combines historical and recent ocean data sets to investigate ice-ocean-interactions along the Pacific continental margin of the West Antarctic Ice Sheet. The synthesis focuses on the strikingly different environments on and near the cold Ross Sea and warm Amundsen Sea continental shelves, where available measurements reach back to ~1958 and 1994, respectively. On the more extensively covered Ross Sea continental shelf, multiple reoccupations of ocean stations and transects are used to extend our knowledge of long-term ocean freshening and the mass balance of the world?s largest ice shelf. On the more rugged Amundsen Sea continental shelf, which contains the earth?s fastest melting ice shelves, continuing research on observed thermohaline variability also pursues connections between outer shelf shoals and vulnerable ice shelf grounding zones. This interdisciplinary work updates a prior study of ice shelf response to ocean thermal forcing, and uses chemical tracers to measure changes in shelf, deep and bottom water transformations and production rates. Broader Impacts : Recent and potential future rates of sea level rise are the primary broad-scale impacts of the ice and ocean changes revealed by observations in the study area. The overriding question is whether global and regional sea levels will accelerate gradually, allowing carbon usage reductions to head off the worst consequences, or so rapidly that they will contribute to major social and economic upheavals. Collaborations and data acquired by foreign vessels are also utilized to better understand the causes of rapid change in these shelf seas and ice shelves, along with associated wider implications. Data that are re-gridded, re-edited or newly collated will be archived, and results made available via presentations, publications, and press releases if warranted. This proposal does not require fieldwork in the Antarctic This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
The continent of Antarctica has approximately the same surface area as the continental United States, though we know significantly less about its underlying geology and seismic activity. Multinational investments in geophysical infrastructure over the last few decades, especially broadband seismometers operating for several years, are allowing us to observe many interesting natural phenomena, including iceberg calving, ice stream slip, and tectonic earthquakes. To specifically leverage those past investments, we will analyze past and current data to gain a better understanding of Antarctic seismicity. Our recent research revealed that certain large earthquakes occurring elsewhere in the world triggered ice movement near various stations throughout Antarctica. We plan to conduct an exhaustive search of the terabytes of available data, using cutting-edge computational techniques, to uncover additional evidence for ice crevassing, ice stream slip, and earth movement during earthquakes. One specific focus of our research will include investigating whether some of these phenomena may be triggered by external influences, including passing surface waves from distant earthquakes, ocean tides, or seasonal melt. We plan to produce a catalog of the identified activity and share it publicly, so the public and researchers can easily access it. To reach a broader audience, we will present talks to high school classes, including Advanced Placement classes, in the Austin, Texas and Atlanta, Georgia metropolitan areas with emphasis on general aspects of seismic hazard, climate variability, and the geographies of Antarctica. This project will provide research opportunities for undergraduates, training for graduate students, and support for an early-career scientist. In recent years, a new generation of geodetic and seismic instrumentation has been deployed as permanent stations throughout Antarctica (POLENET), in addition to stations deployed for shorter duration (less than 3 years) experiments (e.g. AGAP/TAMSEIS). These efforts are providing critical infrastructure needed to address fundamental questions about both crustal-scale tectonic structures and ice sheets, and their interactions. We plan to conduct a systematic detection of tectonic and icequake activities in Antarctica, focusing primarily on background seismicity, remotely-triggered seismicity, and glacier slip events. Our proposed tasks include: (1) Identification of seismicity throughout the Antarctic continent for both tectonic and ice sources. (2) An exhaustive search for additional triggered events in Antarctica during the last ~15 years of global significant earthquakes. (3) Determination of triggered source mechanisms and whether those triggered events also occur at other times, by analyzing years of data using a matched-filter analysis (where the triggered local event is used to detect similar events). (4) Further analysis of GPS measurements over a ~5.5 year period from Whillans Ice Plain, which suggests that triggering of stick-slip events occurred after the largest earthquakes. An improved knowledge of how the Antarctic ice sheet responds to external perturbations such as dynamic stresses from large distant earthquakes and recent ice unloading could lead to a better understanding of ice failure and related dynamic processes. By leveraging the vast logistical investment to install seismometers in Antarctica over the last decade, our project will build an exhaustive catalog of tectonic earthquakes, icequakes, calving events, and any other detectable near-surface seismic phenomena.
Accurately measuring precipitation in Antarctica is important for purposes such as calculating Antarctica?s mass balance and contribution to global sea level rise, interpreting ice core records, and validating model- and satellite-based precipitation estimates. There is a critical need for reliable, autonomous, long-term measurements of Antarctic precipitation in order to better understand its variability in space in time. Such records over time are essentially absent from the continent, despite their importance. This project will deploy and test instrumentation to measure and record rates of snowfall and blowing snow in Antarctica. Project goals are based on installation of four low-power, autonomous Antarctic precipitation systems (APS) co-located at automatic weather station (AWS) sites in the Ross Island region of Antarctica. The APSs are designed with an integrated sensor approach to provide multiple types of observations of snow accumulation types at the test sites. The APSs are designed to construct an accurate timeline of snow accumulation, and to distinguish the water equivalent of fallen precipitation from surface blowing (lofted) snow, a prime confounding factor. The standard suite of instruments to be deployed includes: precipitation gauge with double Alter windshield, laser disdrometer, laser snow height sensor, optical precipitation detector, anemometer at gauge height, and a visible /infrared webcam. These instruments have previously been shown to work well in cold regions applications.
Bromirski/1246151 This award supports a project intended to discover, through field observations and numerical simulations, how ocean wave-induced vibrations on ice shelves in general, and the Ross Ice Shelf (RIS), in particular, can be used (1) to infer spatial and temporal variability of ice shelf mechanical properties, (2) to infer bulk elastic properties from signal propagation characteristics, and (3) to determine whether the RIS response to infragravity (IG) wave forcing observed distant from the front propagates as stress waves from the front or is "locally" generated by IG wave energy penetrating the RIS cavity. The intellectual merit of the work is that ocean gravity waves are dynamic elements of the global ocean environment, affected by ocean warming and changes in ocean and atmospheric circulation patterns. Their evolution may thus drive changes in ice-shelf stability by both mechanical interactions, and potentially increased basal melting, which in turn feed back on sea level rise. Gravity wave-induced signal propagation across ice shelves depends on ice shelf and sub-shelf water cavity geometry (e.g. structure, thickness, crevasse density and orientation), as well as ice shelf physical properties. Emphasis will be placed on observation and modeling of the RIS response to IG wave forcing at periods from 75 to 300 s. Because IG waves are not appreciably damped by sea ice, seasonal monitoring will give insights into the year-round RIS response to this oceanographic forcing. The 3-year project will involve a 24-month period of continuous data collection spanning two annual cycles on the RIS. RIS ice-front array coverage overlaps with a synergistic Ross Sea Mantle Structure (RSMS) study, giving an expanded array beneficial for IG wave localization. The ice-shelf deployment will consist of sixteen stations equipped with broadband seismometers and barometers. Three seismic stations near the RIS front will provide reference response/forcing functions, and measure the variability of the response across the front. A linear seismic array orthogonal to the front will consist of three stations in-line with three RSMS stations. Passive seismic array monitoring will be used to determine the spatial and temporal distribution of ocean wave-induced signal sources along the front of the RIS and estimate ice shelf structure, with the high-density array used to monitor and localize fracture (icequake) activity. The broader impacts include providing baseline measurements to enable detection of ice-shelf changes over coming decades which will help scientists and policy-makers respond to the socio-environmental challenges of climate change and sea-level rise. A postdoctoral scholar in interdisciplinary Earth science will be involved throughout the course of the research. Students at Cuyamaca Community College, San Diego County, will develop and manage a web site for the project to be used as a teaching tool for earth science and oceanography classes, with development of an associated web site on waves for middle school students.
Predictions of future changes of the Antarctic ice sheet are essential for understanding changes in the global sea level expected for the coming centuries. These predictions rely on models of ice-sheet flow that in turn rely on knowledge of the physical conditions of the Antarctic continent beneath the ice. Exploration of Antarctica by land, sea, and air has advanced our understanding of the geological material under the Antarctic ice sheet, but this information has not yet been fully integrated into ice-sheet models. This project will take advantage of existing data from decades of US and international investment in geophysical surveys to create a new understanding of the geology underlying the Amundsen Sea and the adjacent areas of the West Antarctic Ice Sheet—a portion of Antarctica that is considered particularly vulnerable to collapse. A series of new datasets called “Bed Classes” will be developed that will translate the geological properties of the Antarctic continent in ways that can be incorporated into ice-sheet models. This project will develop a new regional geologic/tectonic framework for the Amundsen Sea Embayment and its ice catchments using extensive marine and airborne geophysical data together with ground-based onshore geophysical and geological constraints to delineate sedimentary basins, bedrock ridges, faults, and volcanic structures. Using this new geologic interpretation of the region, several key issues regarding the geologic influence on ice-sheet stability will be addressed: whether the regional heat flow is dominated by localization along the faults or lithology; the role of geology on the sources, sinks, and flow-paths of subglacial water; the distribution of sediments that determine bed-character variability; and the extent of geologic control on the current Thwaites Glacier grounding line. The impact of improved geological knowledge on ice-sheet models will be tested with the development of a set of “Bed Class” grids to capture these new insights for use in the models. Bed Classes will be tested within the Parallel Ice Sheet Model framework with initial experiments to identify the sensitivity of model simulations to geological parameterizations. Through a series of workshops with ice-sheet modelers, the Bed Classes will be refined and made accessible to the broader modelling community. This work aims to ensure that the Bed-Class concept can be applied more broadly to ice-sheet models working in different geographic areas and on different timescales. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
This project contributes to the joint initiative launched by the U.S. National Science Foundation (NSF) and the U.K. Natural Environment Research Council (NERC) to substantially improve decadal and longer-term projections of ice loss and sea-level rise originating from Thwaites Glacier in West Antarctica. Thwaites and neighboring glaciers in the Amundsen Sea Embayment are rapidly losing mass in response to recent climate warming and related changes in ocean circulation. Mass loss from the Amundsen Sea Embayment could lead to the eventual collapse of the West Antarctic Ice Sheet, raising the global sea level by up to 2.5 meters (8 feet) in as short as 500 years. The processes driving the loss appear to be warmer ocean circulation and changes in the width and flow speed of the glacier, but a better understanding of these changes is needed to refine predictions of how the glacier will evolve. One highly sensitive process is the transitional flow of glacier ice from land onto the ocean to become a floating ice shelf. This flow of ice from grounded to floating is affected by changes in air temperature and snowfall at the surface; the speed and thickness of ice feeding it from upstream; and the ocean temperature, salinity, bathymetry, and currents that the ice flows into. The project team will gather new measurements of each of these local environmental conditions so that it can better predict how future changes in air, ocean, or the ice will affect the loss of ice to the ocean in this region. Current and anticipated near-future mass loss from Thwaites Glacier and nearby Amundsen Sea Embayment region is mainly attributed to reduction in ice-shelf buttressing due to sub-ice-shelf melting by intrusion of relatively warm Circumpolar Deep Water into sub-ice-shelf cavities. Such predictions for mass loss, however, still lack understanding of the dominant processes at and near grounding zones, especially their spatial and temporal variability, as well as atmospheric and oceanic drivers of these processes. This project aims to constrain and compare these processes for the Thwaites and the Dotson Ice Shelves, which are connected through upstream ice dynamics, but influenced by different submarine troughs. The team's specific objectives are to: 1) install atmosphere-ice-ocean multi-sensor remote autonomous stations on the ice shelves for two years to provide sub-daily continuous observations of concurrent oceanic, glaciologic, and atmospheric conditions; 2) measure ocean properties on the continental shelf adjacent to ice-shelf fronts (using seal tagging, glider-based and ship-based surveys, and existing moored and conductivity-temperature-depth-cast data), 3) measure ocean properties into sub-ice-shelf cavities (using autonomous underwater vehicles) to detail ocean transports and heat fluxes; and 4) constrain current ice-shelf and sub-ice-shelf cavity geometry, ice flow, and firn properties for the ice-shelves (using radar, active-source seismic, and gravimetric methods) to better understand the impact of ocean and atmosphere on the ice-sheet change. The team will also engage the public and bring awareness to this rapidly changing component of the cryosphere through a "Live from the Ice" social media campaign in which the public can follow the action and data collection from the perspective of tagged seals and autonomous stations. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Gerbi/1643301 This award supports a project to develop software that will allow researchers considering seismic or radar field surveys to test, ahead of time, whether the data they plan to collect will have sufficient resolution to measure the natural variations in the mechanical properties of ice, which determine the response of flowing ice to changing climatic conditions. The mechanical properties of ice depend largely on the temperature and the orientation of the crystals that make up the ice. The most accurate method for measuring ice crystal orientation and temperature is through drilling and direct analysis of an ice core. However, this method is very costly, time-consuming, and limited in spatial coverage. Geophysical techniques, such as seismic and radar, can cover much more area, but we have little knowledge about the practical limitations of these techniques as they relate to calculating mechanical properties. This project addresses that knowledge gap through construction of a computational toolbox that will allow accurate assessment of the ability of geophysical surveys to image crystal orientation and ice temperature. Researchers can then use these tools to adjust the field survey plans to maximize the return on investment. By working to improve the efficiency and effectiveness of future geophysical work related to glacial flow, this proposal will improve scientists? ability to quantify sea-level variations within the larger context of climate change. The project includes building new user-friendly, publicly accessible software and instructional modules. The work will provide training for graduate and undergraduate students, who will play a role in research and develop instructional materials. Ice viscosity, the resistance of ice to flow, exerts significant control over ice velocity. Therefore, mapping ice viscosity is important for understanding the current and future behavior of glaciers and ice sheets. To do so, scientists must determine the temperature and crystal orientation fabric throughout the ice. Seismic and radar techniques can survey large areas quickly, and thus are promising, yet not fully tested, methods to efficiently measure the thermal and mechanical structure of flowing ice. As part of this project, scientists will develop and use a computational framework to quantify the degree to which seismic and radar techniques can resolve the crystal orientation fabric and temperature of streaming ice, and then test how sensitive ice flow is to the attendant uncertainty. To meet these goals, a numerical toolbox will be built which will allow the glacier/ice stream geometry and physical properties (temperature, crystal orientation fabric, density and acidity) to be varied. The toolbox will be capable of both creating synthetic radar and seismic profiles through forward modeling and inverting synthetic profiles to allow evaluation of how well geophysical techniques can image the original thermal and mechanical structure. These simulated radar and seismic data will allow scientists to better quantify the influence of the variability in mechanical properties of the ice on flow velocities and patterns. The results of this work will guide planning for future field campaigns, making them more effective and efficient. This project does not require fieldwork in the Antarctic.
This project will acquire measurements of the concentration of beryllium-10 (10Be) from an ice core from the South Pole, Antarctica. An isotope of the element beryllium, 10Be, is produced in the atmosphere by high-energy protons (cosmic rays) that enter Earth's atmosphere from space. It is removed from the atmosphere by settling or by scavenging by rain or snowfall. Hence, concentrations of 10Be in snow at the South Pole reflect the production rate of 10Be in the atmosphere. Because the rate of production of 10Be over Antarctica depends primarily on the strength of the Sun's magnetic field, measurements of 10Be in the South Pole ice core will provide a record of changes in solar activity. The South Pole ice core will reach an age of 40,000 years at the bottom. The project will result in measurements of 10Be at annual resolution for the last 100 years and selected periods in the more distant past, such as the Maunder Minimum, a period during the late 17th century during which no sunspots were observed, or the last glacial cold period, about 20,000 years ago. A climate model that can simulate the production of 10Be in the atmosphere, it's transport through the atmosphere, and its deposition at the snow surface in Antarctica will be used to aid in using the 10Be data to determine past changes in solar activity from decadal to millennial scale, and in turn to evaluate the role of the Sun in Earth?s climate from a new perspective. The production of 10Be in Earth's atmosphere results from the spallation of oxygen and nitrogen in the atmosphere by cosmic rays. Cosmic ray variations in the high latitudes are primarily modulated by solar variability. Time-series records of 10Be from ice cores are therefore important for deriving variations in solar activity through time, which is fundamental to understanding climate variability. Deposition of 10Be to the ice surface is also influenced by variability in atmospheric circulation and deposition processes, and South Pole is the best available location for minimizing the influence of variable atmospheric circulation on 10Be deposition. To date, only one record of 10Be exists from South Pole; that record is widely used in solar forcing estimates used in climate models, but covers only the last millennium and ends in CE 1982. We will obtain 10Be concentration measurements in a 1500-m, 40000-year long ice core from the South Pole. This will extend the existing record both further back in time and forward to the present, providing overlap with the modern instrumental record of solar and climate variability. High resolution (annual to biannual) measurements will be made in targeted areas of interest, including the last 100 years, the Maunder Minimum (CE 1650-1715), and the last glacial maximum. The novel data will be used in conjunction with climate model experiments that incorporate 10Be production, transport, and deposition physics. Together, data and modeling will create an updated record of atmospheric 10Be production and hence of solar activity.
This investigation will reconstruct past behavior of the East Antarctic Ice Sheet during periods of warmer-than-present climate, such as the Pliocene, in order to better project the likely response of Earth's largest ice sheet to anthropogenic warming. Containing the equivalent of ~55 m sea-level rise, the future evolution of the East Antarctic Ice Sheet has clear societal ramifications on a global scale as temperatures continue to rise. Therefore, determining ice-sheet sensitivity to climate on the scale predicted for the next two centuries is a matter of increasing urgency, particularly in light of evidence suggesting the East Antarctic Ice Sheet is more dynamic than previously thought. This research will provide a terrestrial geologic record of long-term ice-sheet behavior from sites immediately adjacent the East Antarctic Ice Sheet in the Transantarctic Mountains, with which the project will help ascertain how the ice sheet responded to past warm periods. The project will focus primarily on the Pliocene warm period, 5 to 3 million years ago, as this represents the closest analogue to 21st Century climate conditions. The proposed research will investigate glacial deposits corresponding to the East Antarctic Ice Sheet in the central Transantarctic Mountains in order to expand the geologic record of past ice-sheet behavior. The overarching research objectives are to improve understanding of the East Antarctic Ice Sheet's configuration during periods of warmer-than-present climate, such as the Pliocene warm period, and to determine whether the ice sheet underwent significant volume changes or remained relatively stable in response to warming. To address these goals, the investigation will map and date glacial deposits preserved at mountain sites immediately adjacent the ice sheet. Specifically, we will: (i) employ multiple cosmogenic nuclides (10Be, 26Al, 21Ne) to establish more fully ice-thickness histories for the upper Shackleton and Beardmore Glaciers, where they exit the ice sheet; (ii) use this record to identify periods during which the East Antarctic Ice Sheet was at least as extensive as today; and (iii) use these data to assess long-term ice-sheet variability in East Antarctica, with particular emphasis on Pliocene warm episodes. This research will require Antarctic fieldwork, glacial-geologic mapping, and cosmogenic surface-exposure dating.
Nontechnical Description Glacier ice loss from Antarctica has the potential to lead to a significant rise in global sea level. One line of evidence for accelerated glacier ice loss has been an increase in the rate at which the land has been rising across the Antarctic Peninsula as measured by GPS receivers. However, GPS observations of uplift are limited to the last two decades. One goal of this study is to determine how these newly observed rates of uplift compare to average rates of uplift across the Antarctic Peninsula over a longer time interval. Researchers will reconstruct past sea levels using the age and elevation of ancient beaches now stranded above sea level on the low-lying coastal hills of the Antarctica Peninsula to determine the rate of uplift over the last 5,000 years. The researchers will also analyze the structure of the beaches using ground-penetrating radar and the characteristics of beach sediments to understand how sea-level rise and past climate changes are recorded in beach deposits. The benefits of these new records will be threefold: (1) they will help determine the natural variability of the Antarctic Ice Sheet and relative sea level (2) they will provide new insight about uplift and the structure of the Earth's interior; and 3) they will help researchers refine the methods used to determine the age of geologic deposits. The study results will be shared in outreach events at K-12 schools and with visitors of the Santa Barbara Natural History Museum. Three graduate students will be supported through this project. Technical description Paleo sea-level data is critical for reconstructing the size and extent of past ice sheets, documenting increased uplift following glacial retreat, and correcting gravity-based measurements of ice-mass loss for the impacts of post-glacial rebound. However, there are only 14 sites with relative sea-level data for Antarctica compared to over 500 sites used in a recent study of the North American Ice-Sheet complex. The purpose of this project is to use optically stimulated luminescence to date a series of newly discovered raised beaches along the eastern Antarctic Peninsula and an already known, but only preliminarily dated, series of raised beaches in the South Shetland Islands. Data to be collected at the raised beaches include the age and elevation, ground-penetrating radar profiles, and the roundness of cobbles and the lithology of ice-rafted debris. The study will test three hypotheses: (1) uplift rates have increased in modern times relative to the late Holocene across the Antarctic Peninsula, (2) the sea-level history at the northern tip of the Antarctic Peninsula is distinctly different than that of the South Shetland Islands, and (3) cobble roundness and the source of ice-rafted debris on raised beaches varied systematically through time reflecting the climate history of the northern Antarctic Peninsula.
Scientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth's ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. Work proposed here will test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement will be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work will contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. The proposed work will add a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that will collect sediment cores at three to five locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170°W. The goal is to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. In the proposed work the radiocarbon age of foraminifera that inhabited the surface ocean will be compared with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms will be used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it is expected that surface and deep-dwelling foraminifera will exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters return to the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work is to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean?s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarcitca.
The ocean tide is a large component of total variability of ocean surface height and currents in the seas surrounding Antarctica, including under the floating ice shelves. Maximum tidal height range exceeds 7 m (near the grounding line of Rutford Ice Stream) and maximum tidal currents exceed 1 m/s (near the shelf break in the northwest Ross Sea). Tides contribute to several important climate and ecosystems processes including: ocean mixing, production of dense bottom water, flow of warm Circumpolar Deep Water onto the continental shelves, melting at the bases of ice shelves, fracturing of the ice sheet near a glacier or ice stream’s grounding line, production and decay of sea ice, and sediment resuspension. Tide heights and, in particular, currents can change as the ocean background state changes, and as the geometry of the coastal margins of the Antarctic Ice Sheet varies through ice shelf thickness changes and ice-front and grounding-line advances or retreats. For satellite-based studies of ocean surface height and ice shelf thickness changes, tide heights are a source of substantial noise that must be removed. Similarly, tidal currents can also be a substantial noise signal when trying to estimate mean ocean currents from short-term measurements such as from acoustic Doppler current profilers mounted on ships and CTD rosettes. Therefore, tide models play critical roles in understanding current and future ocean and ice states, and as a method for removing tides in various measurements. A paper in Reviews of Geophysics (Padman, Siegfried and Fricker, 2018, see list of project-related publications below) provides a detailed review of tides and tidal processes around Antarctica.
This project provides a gateway to tide models and a database of tide height coefficients at the Antarctic Data Center, and links to toolboxes to work with these models and data.
Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced "fracture zone canyons" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation.
Modeling fluctuations in the extent of the West Antarctic Ice Sheet (WAIS) over time is a principal goal of the glaciological community. These models will provide a critical basis for predictions of future sea level change, and therefore this work great societal relevance. The mid-Pliocene time interval is of particular interest, as it is the most recent period in which global temperatures were warmer and atmospheric CO2 concentrations may have been higher than current levels. However, observational constraints on fluctuations in the WAIS older than the last glacial maximum are rare. The investigators propose to collect geochemical data from the Ohio Range and Scott Glacier to quantify past variability in the height of the WAIS. Limited available cosmogenic nuclide data are broadly consistent with a model indicating that Pliocene WAIS elevations and volumes were smaller than at present, and that WAIS collapse was common. The PIs will use geologic observations and cosmogenic nuclide concentrations from bedrock samples at multiple locations and at multiple elevations, including sub-ice samples, to constrain WAIS ice volume changes in a "dipstick" like fashion. Data obtained from the proposed research will provide targets for data-ice sheet model comparisons to accurately characterize Plio-Pleistocene and future WAIS behavior. As part of this project, the investigators will work with the Natural History Museum and the Earth & Planetary Science department at Harvard to develop an exhibit that will become part of the Museum's recently opened Earth and Planetary Science Gallery. The project involves mentoring of a female graduate student as well as an undergraduate student.
1142167/Pettit This award supports a project to develop a better understanding of the relation between ice microstructure, impurities, and ice flow and their connection to climate history for the West Antarctic Ice Sheet (WAIS) ice core site. This work builds on several ongoing studies at Siple Dome in West Antarctica and Dome C in East Antarctica. It is well known that the microstructure of ice evolves with depth and time in an ice sheet. This evolution of microstructure depends on the ice flow field, temperature, and impurity content. The ice flow field, in turn, depends on microstructure, leading to feedbacks that create layered variation in microstructure that relates to climate and flow history. The research proposed here focuses on developing a better understanding of: 1) how ice microstructure evolves with time and stress in an ice sheet and how that relates to impurity content, temperature, and strain rate; 2) how variations in ice microstructure and impurity content affect ice flow patterns near ice divides (on both small (1cm to 1m) and large (1m to 100km) scales); and 3) in what ways is the spatial variability of ice microstructure and its effect on ice flow important for interpretation of climate history in the WAIS Divide ice core. The study will integrate existing ice core and borehole data with a detailed study of ice microstructure using Electron Backscatter Diffraction (EBSD) techniques and measurements of borehole deformation through time using Acoustic Televiewers. This will be the first study to combine these two novel techniques for studying the relation between microstructure and deformation and it will build on other data being collected as part of other WAIS Divide borehole logging projects (e.g. sonic velocity, optical dust logging, temperature and other measurements on the ice core including fabric measurements from thin section analyses as well as studies of ice chemistry and stable isotopes. The intellectual merit of the work is that it will improve interpretation of ice core data (especially information on past accumulation) and overall understanding of ice flow. The broader impacts are that the work will ultimately contribute to a better interpretation of ice core records for both paleoclimate studies and for ice flow history, both of which connect to the broader questions of the role of ice in the climate system. The work will also advance the careers of two early-career female scientists, including one with a hearing impairment disability. This project will support a PhD student at the UAF and provide research and field experience for two or three undergraduates at Dartmouth. The PIs plan to include a teacher on their field team and collaborate with UAF's "From STEM to STEAM" toward enhancing the connection between art and science.
Bell and Buck: OPP 9615704 Blankenship: OPP 9615832 Abstract Continental extension produces a great variety of structures from the linear narrow rifts of the East African Rift to the diffuse extension of the Basin and Range Province of the Western U.S. Rift shoulder uplift varies dramatically between rift flanks. The cause of variable rift width and crustal thinning is fairly well explained by variable initial heat flow and crustal thickness. Mechanical stretching of the lithosphere has been linked to rift shoulder uplift but the cause of variable rift flank uplift remains poorly understood. The Transantarctic Mountains (TAM) are an extreme example of rift flank uplift, extending over 3500 km across Antarctica and reaching elevations up to 4500 m and thus constitute a unique feature of EarthOs crust. The range was formed in the extensional environment associated with the Mesozoic and Cenozoic breakup of Gondwanaland. Geological and geophysical work has shown that the TAM developed along the long-lived lithospheric boundary between East and West Antarctica reactivated by a complex history of extensional and translational microplate motions. The TAM are not uniform along strike. Along the OWilkes FrontO, the northern segment of the rift extends from North Victoria Land to Byrd Glacier. The Wilkes Front architecture consists of (1) thin, extended crust forming the Victoria Land Basin in the Ross Sea, (2) the TAM rift shoulder, and (3) a long-wavelength down- ward forming the Wilkes Basin. Contrasting structures are mapped along the OPensacola/PoleO Front, the southern segment of the rift extending from the Nimrod Glacier to the Pensacola Mountains. Along this southern section no rift basin has been mapped to date and the down-ward along the East Antarctic, or ObacksideO, edge of the mountains is less pronounced. A flexural model linking the extension in the Ross Sea to the formation of both the mountains and the Wilkes Basin has been considered as a me chanism for uplift of the entire mountain range. The variability in fundamental architecture along the TAM indicates that neither a single event nor a sequence of identical events produced the rift flank uplift. The observation of variable architecture suggests complex mechanisms and possibly a fundamental limitation in maximum sustainable rift flank elevation. The motivation for studying the TAM is to try to understand the geodynamics of this extreme elevation rift flank. Are the geodynamics of the area unique, or does the history of glaciation and related erosion contribute to the extreme uplift? With the existing data sets it is difficult to confidently constrain the geological architecture across representative sections of the TAM. Any effort to refine geodynamic mechanisms requires this basic understanding of the TAM architecture. The goal of this project is to (1) constrain the architecture of the rift system as well as the distribution and structure of sedimentary basins, glacial erosion and mafic igneous rocks surrounding the rift flank by acquiring three long wavelength geophysical transects with integrated gravity, magnetics, ice- penetrating radar, and ice surface measurements, (2) quantify the contribution of various geodynamic mechanisms to understand the geological conditions which can lead to extreme rift flank uplift, and (3) use the improved understanding of architecture and geophysical data to test geodynamic models in order to improve our understanding both of the TAM geodynamics and the general problem of the geodynamics of rift flank uplift worldwide. This project will allow development of a generalized framework for understanding the development of rift flank uplift as well as address the question of the specific geodynamic evolution of the TAM.
In the past, Earth's climate underwent dramatic changes that influenced physical, chemical, geological, and biological processes on a global scale. Such changes left an imprint in Earth's atmosphere, as shown by the variability in abundances of trace gases like carbon dioxide and methane. In return, changes in the atmospheric trace gas composition affected Earth's climate. Studying compositional variations of the past atmosphere helps us understand the history of interactions between global biogeochemical cycles and Earth?s climate. The most reliable information on past atmospheric composition comes from analysis of air entrapped in polar ice cores. This project aims to generate ice-core records of relatively short-lived, very-low-abundance trace gases to determine the range of past variability in their atmospheric levels and investigate the changes in global biogeochemical cycles that caused this variability. This project measures three such gases: carbonyl sulfide, methyl chloride, and methyl bromide. Changes in carbonyl sulfide can indicate changes in primary productivity and photosynthetic update of carbon dioxide. Changes in methyl chloride and methyl bromide significantly impact natural variability in stratospheric ozone. In addition, the processes that control atmospheric levels of methyl chloride and methyl bromide are shared with those controlling levels of atmospheric methane. The measurements will be made in the new ice core from the South Pole, which is expected to provide a 40,000-year record. The primary focus of this project is to develop high-quality trace gas records for the entire Holocene period (the past 11,000 years), with additional, more exploratory measurements from the last glacial period including the period from 29,000-36,000 years ago when there were large changes in atmospheric methane. Due to the cold temperatures of the South Pole ice, the proposed carbonyl sulfide measurements are expected to provide a direct measure of the past atmospheric variability of this gas without the large hydrolysis corrections that are necessary for interpretation of measurements from ice cores in warmer settings. Furthermore, we will test the expectation that contemporaneous measurements from the last glacial period in the deep West Antarctic Ice Sheet Divide ice core will not require hydrolysis loss corrections. With respect to methyl chloride, we aim to verify and improve the existing Holocene atmospheric history from the Taylor Dome ice core in Antarctica. The higher resolution of our measurements compared with those from Taylor Dome will allow us to derive a more statistically significant relationship between methyl chloride and methane. With respect to methyl bromide, we plan to extend the existing 2,000-year database to 11,000 years. Together, the methyl bromide and methyl chloride records will provide strong measurement-based constraints on the natural variability of stratospheric halogens during the Holocene period. In addition, the methyl bromide record will provide insight into the correlation between methyl chloride and methane during the Holocene period due to common sources and sinks.
Collaborative Proposal: A field and laboratory examination of the diatom N and Si isotope proxies: Implications for assessing the Southern Ocean biological pump The rise in atmospheric carbon dioxide concentrations and associated climate changes make understanding the role of the ocean in large scale carbon cycle a priority. Geologic samples allow exploration of potential mechanisms for carbon dioxide drawdown during glacial periods through the use of geochemical proxies. Nitrogen and silicon isotope signatures from fossil diatoms (microscopic plants) are used to investigate changes in the physical supply and biological demand for nutrients (like nitrogen and silicon and carbon) in the Southern Ocean. The project will evaluate the use the nitrogen and silicon isotope proxies through a series of laboratory experiments and Southern Ocean field sampling. The results will provide quantification of real relationships between nitrogen and silicon isotopes and nutrient usage in the Southern Ocean and allow exploration of the role of other factors, including biological diversity, ice cover, and mixing, in altering the chemical signatures recorded by diatoms. Seafloor sediment samples will be used to evaluate how well the signal created in the water column is recorded by fossil diatoms buried in the seafloor. Improving the nutrient isotope proxies will allow for a more quantitative understanding of the role of polar biology in regulating natural variation in atmospheric carbon dioxide. The project will also result in the training of a graduate student and development of outreach materials targeting a broad popular audience. This project seeks to test the fidelity of the diatom nitrogen and silicon isotope proxies, two commonly used paleoceanographic tools for investigating the role of the Southern Ocean biological pump in regulating atmospheric CO2 concentrations on glacial-interglacial timescales. Existing ground-truthing data, including culture experiments, surface sediment data and downcore reconstructions, all suggest that nutrient utilization is the primary driver of isotopic variation in the Southern Ocean. However, strong contribution of interspecific variation is implied by recent culture results. Moreover, field and laboratory studies present some contradictory results in terms of the relative importance of interspecific variation and of inferred post-depositional alteration of the nutrient isotope signals. Here, a first order test of the N and Si diatom nutrient isotope paleo-proxies, involving water column dissolved and particulate sampling and laboratory culturing of field-isolates, is proposed. Southern Ocean water, biomass, live diatoms and fossil diatom sampling will be conducted to investigate species and assemblage related variability in diatom nitrogen and silicon isotopes and their relationship to surface nutrient fields and early diagenesis. Access to fresh materials produced in an analogous environmental context to the sediments of primary interest is critical for making robust paleoceanographic reconstructions. Field sampling will occur along 175°W, transecting the Antarctic Circumpolar Current from the subtropics to the marginal ice edge. Collection of water, sinking/suspended particles and multi-core samples from 13 stations and 3 shipboard incubation experiments will be used to test four proposed hypotheses that together evaluate the significance of existing culture results and seek to allow the best use of diatom nutrient isotope proxies in evaluating the biological pump.
This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible. This project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.
1142517/Saltzman This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.
The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (<20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change. This research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.
During winter, sea-ice coverage along the Antarctic coast is punctuated by numerous polynyas--isolated openings of tens to hundreds of kilometer wide. These coastal polynyas are hotspots of sea ice production and the primary source regions of the bottom water in the global ocean. They also host high levels of biological activities and are the feeding grounds of Emperor penguins and marine mammals. The polynyas are a key component of the Antarctic coastal system and crucial for the survival of penguins and many other species. These features also differ dramatically from each other in timing of formation, duration, phytoplankton growth season, and overall biological productivity. Yet, the underlying reasons for differences among them are largely unknown. This project studies the fundamental biophysical processes at a variety of polynyas, examines the connection between the physical environment and the phytoplankton and penguin ecology, and investigates the mechanisms behind polynya variability. The results of this interdisciplinary study will provide a context for interpretation of field measurements in Antarctic coastal polynyas, set a baseline for future polynya studies, and examine how polynya ecosystems may respond to local and large-scale environmental changes. The project will include educational and outreach activities that convey scientific messages to a broad audience. It aims to increase public awareness of the interconnection between large-scale environmental change and Antarctic coastal systems. The main objectives of this study are to form a comprehensive understanding of the temporal and spatial variability of Antarctic coastal polynyas and the physical controls of polynya ecosystems. The project takes an interdisciplinary approach and seeks to establish a modeling system centered on the Regional Ocean Modeling System. This system links the ice and ocean conditions to the plankton ecology and penguin population. Applications of the modeling system in representative polynyas, in conjunction with analysis of existing observations, will determine the biophysical influences of individual forcing factors. In particular, this study will test a set of hypothesized effects of winds, offshore water intrusion, ice-shelf melting, sea-ice formation, glacier tongues, and ocean stratification on the timing of polynya phytoplankton bloom and the overall polynya biological productivity. The project will also examine how changing polynya state affects penguin breeding success, adult survival, and population growth. The team will conduct idealized sensitivity analysis to explore implications of forcing variability, including local and large-scale environmental change, on Antarctic coastal ecosystems.
The Weddell seal is the southern-most mammal in the world, having a circumpolar distribution around Antarctica; the McMurdo Sound population in Antarctica is one of the best-studied mammal populations on earth. However, despite this, an understanding of how populations around the continent will fare under climate change is poorly understood. A complicating matter is the potential effects of a commercial enterprise in the Antarctic: a fishery targeting toothfish, which are important prey for Weddell seals. Although the species is easily detected and counted during the breeding season, no reliable estimates of continent-wide Weddell seal numbers exist, due to the logistic difficulties of surveying vast regions of Antarctica. Large-scale estimates are needed to understand how seal populations are responding to the fishery and climate change, because these drivers of change operate at scales larger than any single population, and may affect seals differently in different regions of the continent. We will take advantage of the ease of detectability of darkly colored seals when they the on ice to develop estimates of abundance from satellite images. This project will generate baseline data on the global distribution and abundance of Weddell seals around the Antarctic and will link environmental variables to population changes to better understand how the species will fare as their sea ice habitat continues to change. These results will help disentangle the effects of climate change and fishery operations, results that are necessary for appropriate international policy regarding fishery catch limits, impacts on the environment, and the value of marine protected areas. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. It will engage "arm-chair" scientists of all ages through connections with several non-governmental organizations and the general public. Anyone with access to the internet, including people who are physically unable to participate in field research directly, can participate in this project while simultaneously learning about multiple aspects of polar ecology through the project's interactive website. Specifically, this research project will: 1) Quantify the distribution of Weddell seals around Antarctica and 2) Determine the impact of environmental variables (such as fast ice extent, ocean productivity, bathymetry) on habitat suitability and occupancy. To do this, the project will crowd-source counting of seals on high-resolution satellite images via a commercial citizen science platform. Variation in seal around the continent will then be related to habitat variables through generalized linear models. Specific variables, such as fast ice extent will be tested to determine their influence on population variability through both space and time. The project includes a rigorous plan for ensuring quality control in the dataset including ground truth data from other, localized projects concurrently funded by the National Science Foundation's Antarctic Science Program.
Brook 1543267 Approximately half of the human caused carbon dioxide emissions to the atmosphere are absorbed by the ocean, which reduces the amount of global warming associated with these emissions. Much of this carbon uptake occurs in the Southern Ocean around Antarctica, where water from the deep ocean comes to the surface. How much water "up-wells," and therefore how much carbon is absorbed, is believed to depend on the strength and location of the major westerly winds in the southern hemisphere. These wind patterns have been shifting southward in recent decades, and future changes could impact the global carbon cycle and promote the circulation of relatively warm water from the deep ocean on to the continental shelf, which contributes to enhanced Antarctic ice melt and sea level rise. Understanding of the westerly winds and their role in controlling atmospheric carbon dioxide levels and the circulation of ocean water is therefore very important. The work supported by this award will study past movement of the SH westerlies in response to natural climate variations. Of particular interest is the last deglaciation (20,000 to 10,000 years ago), when the global climate made a transition from an ice age climate to the current warm period. During this period, atmospheric carbon dioxide rose from about 180 ppm to 270 parts per million, and one leading hypothesis is that the rise in carbon dioxide was driven by a southward movement of the southern hemisphere westerlies. The broader impacts of the work include a perspective on past movement of the southern hemisphere westerlies and their link to atmospheric carbon dioxide, which could guide projections of future oceanic carbon dioxide uptake, with strong societal benefits; international collaboration with German scientists; training of a postdoctoral investigator; and outreach to public schools. This project will investigate whether the abundance of a noble gas, krypton-86, trapped in Antarctic ice cores, records atmospheric pressure variability, and whether or not this pressure variability can be used to infer past movement of the Southern Hemisphere westerly winds. The rationale for the project is that models of air movement in the snow pack (firn) in Antarctica indicate that pressure variations drive air movement that disturbs the normal enrichment in krypton-86 caused by gravitational settling of gases. Calculations predict that the krypton-86 deviation from gravitational equilibrium reflects the magnitude of pressure variations. In turn, atmospheric data show that pressure variability over Antarctica is linked to the position of the southern hemisphere westerly winds. Preliminary data from the West Antarctic Ice Sheet (WAIS) Divide ice core show a large excursion in krypton-86 during the transition from the last ice age to the current warm period. The investigators will perform krypton-86 analysis on ice core and firn air samples to establish whether the Kr-86 deviation is linked to pressure variability, refine the record of krypton isotopes from the WAIS Divide ice core, investigate the role of pressure variability in firn air transport using firn air models, and investigate how barometric pressure variability in Antarctica is linked to the position/strength of the SH westerlies in past and present climates.
Intellectual Merit: Ice free rock outcrops in the Transantarctic Mountains provide the only accessible windows into the interior of the ice covered Antarctic continent; they are extremely remote and difficult to study. This region also hosts the highest latitude ice-free valley systems on the planet. Based on two interdisciplinary workshops, the Transantarctic region near the Shackleton Glacier has been identified as a high priority site for further studies, with a field camp proposed for the 2015-2016 Antarctic field season. The geology of this region has been studied since the heroic era of Antarctic exploration, in the early 1900s, but geologic mapping has not been updated in more than forty years, and existing maps are at poor resolution (typically 1:250,000). This project would utilize the WorldView-2 multispectral orbital dataset to supplement original geologic mapping efforts near the proposed 2015-2016 Shackleton Glacier camp. The WorldView-2 satellite is the only multispectral orbiting sensor capable of imaging the entirety of the Transantarctic Mountains, and all necessary data are currently available to the Polar Geospatial Center. High-latitude atmospheric correction of multispectral data for geologic investigations has only recently been tested, but has never been applied to WorldView-2 data, and never for observations of this type. Therefore, this research will require technique refinements and methodological developements to accomplish the goals. Atmospheric correction refinements and spectral validation will be made possible by laboratory spectroscopic measurements of rock samples currently stored at the U.S. Polar Rock Repository, at the Ohio State University. This project will result in spectral unit identification and boundary mapping at a factor of four higher resolution (1:62,500) than previous geologic mapping efforts, and more detailed investigations (1:5,123) are possible at resolutions more than a factor of forty-eight improved over previous geologic maps. Validated spectral mapping at these improved resolutions will allow for detailed lithologic, and potentially biologic, mapping using existing satellite imagery. This will greatly enhance planning capabilities, thus maximizing the efficiency of the scientific research and support logistics associated with the Shackleton Glacier deep field camp. Broader impacts: The proposed work will have multiple impacts on the broader scientific community. First, the refinement of existing atmospheric correction methodologies, and the development of new spectral mapping techniques, may substantially improve our ability to remotely investigate geologic surfaces throughout Antarctica. The ability to validate this orbital dataset will be of use to both current and future geologic, environmental, and biologic studies, potentially across the entire continent. The project will yield a specific spectral mapping product (at a scale of 1:62,500) to the scientific community by a targeted date of 01 March 2014, in order to support proposals submitted to the National Science Foundation for the proposed 2015/2016 Shackleton Glacier camp. High-resolution spectral mapping products (up to a maximum resolution of 2 meters per pixel) will also be generated for regions of particular scientific interest. The use of community based resources, such as Polar Geospatial Center (PGC) imagery and U.S. Polar Rock Repository rock samples, will generate new synergistic and collaborative research possibilities within the Antarctic research community. In addition, the lead PI (Salvatore) is an early career scientist who is active in both Antarctic and planetary remote sensing. There are overlaps in the calibration, correction, and validation of remote spectral datasets for Antarctic and planetary applications which can lead to benefits and insights to an early career PI, as well as the two communities.
Aydin/1644245 This award supports a project to measure ethane in ice core air extracted from the recently drilled intermediate depth South Pole ice core (SPICECORE). Ethane is an abundant hydrocarbon in the atmosphere. The ice core samples that will be used in this analysis will span about 150 years before present to about 55,000 years before present and therefore, ethane emissions linked to human activities are not a subject of this study. The study will focus on quantifying the variability in the natural sources of ethane and the processes that govern its removal from the atmosphere. A long-term ice core ethane record will provide new knowledge on the chemistry of Earth?s atmosphere during time periods when human influence was either much smaller than present day or non-existent. The broader impacts of this work include education and training of students and a contribution to a better understanding of the chemistry of the atmosphere in the past and how it has been impacted by past changes in climate. Natural sources that emit ethane are both geologic (e.g. seeps, vents, mud volcanoes etc.) and pyrogenic (wild fires) which is commonly called biomass burning. Ethane is removed from the atmosphere via oxidation reactions. The ice core ethane measurements have great potential as a proxy for gaseous emissions from biomass burning. This is especially true for time periods preceding the industrial revolution when atmospheric variability of trace gases was largely controlled by natural processes. Another objective of this study is to improve understanding of the causes of atmospheric methane variability apparent which are in the existing ice core records. Methane is a simpler hydrocarbon than ethane and more abundant in the atmosphere. Even though the project does not include any methane measurements; the commonalities between the sources and removal of atmospheric ethane and methane mean that ethane measurements can be used to gain insight into the causes of changes in atmospheric methane levels. The broader impacts of the project include partial support for one Ph.D. student and support for undergraduate researchers at UC Irvine. The PIs group currently has 4 undergraduate researchers. The PI and the graduate students in the UCI ice core laboratory regularly participate in on- and off-campus activities such as laboratory tours and lectures directed towards educating high-school students and science teachers, and the local community at large about the scientific value of polar ice cores as an environmental record of our planet's past. The results of this research will be disseminated via peer-review publications and will contribute to policy-relevant activities such as the IPCC Climate Assessment. Data resulting from this project will be archived in a national data repository. This award does not have field work in Antarctica.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The LISSARD project (Lake and Ice Stream Subglacial Access Research Drilling) is one of three research components of the WISSARD integrative initiative (Whillans Ice Stream Subglacial Access Research Drilling) that is being funded by the Antarctic Integrated System Science Program of NSF's Office of Polar Programs, Antarctic Division. The overarching scientific objective of WISSARD is to assess the role of water beneath a West Antarctic ice stream in interlinked glaciological, geological, microbiological, geochemical, and oceanographic systems. The LISSARD component of WISSARD focuses on the role of active subglacial lakes in determining how fast the West Antarctic ice sheet loses mass to the global ocean and influences global sea level changes. The importance of Antarctic subglacial lakes has only been recently recognized, and the lakes have been identified as high priority targets for scientific investigations because of their unknown contributions to ice sheet stability under future global warming scenarios. LISSARD has several primary science goals: A) To provide an observational basis for improving treatments of subglacial hydrological and mechanical processes in models of ice sheet mass balance and stability; B) To reconstruct the past history of ice stream stability by analyzing archives of past basal water and ice flow variability contained in subglacial sediments, porewater, lake water, and basal accreted ice; C) To provide background understanding of subglacial lake environments to benefit RAGES and GBASE (the other two components of the WISSARD project); and D) To synthesize data and concepts developed as part of this project to determine whether subglacial lakes play an important role in (de)stabilizing Antarctic ice sheets. We propose an unprecedented synthesis of approaches to studying ice sheet processes, including: (1) satellite remote sensing, (2) surface geophysics, (3) borehole observations and measurements and, (4) basal and subglacial sampling. <br/><br/>INTELLECTUAL MERIT: The latest report of the Intergovernmental Panel on Climate Change recognized that the greatest uncertainties in assessing future global sea-level change stem from a poor understanding of ice sheet dynamics and ice sheet vulnerability to oceanic and atmospheric warming. Disintegration of the WAIS (West Antarctic Ice Sheet) alone would contribute 3-5 m to global sea-level rise, making WAIS a focus of scientific concern due to its potential susceptibility to internal or ocean-driven instability. The overall WISSARD project will test the overarching hypothesis that active water drainage connects various subglacial environments and exerts major control on ice sheet flow, geochemistry, metabolic and phylogenetic diversity, and biogeochemical transformations. <br/><br/>BROADER IMPACTS: Societal Relevance: Global warming, melting of ice sheets and consequential sea-level rise are of high societal relevance. Science Resource Development: After a 9-year hiatus WISSARD will provide the US-science community with a renewed capability to access and study sub-ice sheet environments. Developing this technological infrastructure will benefit the broader science community and assets will be accessible for future use through the NSF-OPP drilling contractor. Furthermore, these projects will pioneer an approach implementing recommendations from the National Research Council committee on Principles of Environmental Stewardship for the Exploration and Study of Subglacial Environments (2007). Education and Outreach (E/O): These activities are grouped into four categories: i) increasing student participation in polar research by fully integrating them in our research programs; ii) introducing new investigators to the polar sciences by incorporating promising young investigators in our programs, iii) promotion of K-12 teaching and learning programs by incorporating various teachers and NSTA programs, and iv) reaching a larger public audience through such venues as popular science magazines, museum based activities and videography and documentary films. In summary, WISSARD will promote scientific exploration of Antarctica by conveying to the public the excitement of accessing and studying what may be some of the last unexplored aquatic environments on Earth, and which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.
Conway/1141866 This award supports a project to conduct a suite of experiments to study spatial and temporal variations of basal conditions beneath Beardmore Glacier, an East Antarctic outlet glacier that discharges into the Ross Sea Embayment. The intellectual merit of the project is that it should help verify whether or not global warming will play a much larger role in the future mass balance of ice sheets than previously considered. Recent observations of rapid changes in discharge of fast-flowing outlet glaciers and ice streams suggest that dynamical responses to warming could affect that ice sheets of Greenland and Antarctica. Assessment of possible consequences of these responses is hampered by the lack of information about the basal boundary conditions. The leading hypothesis is that variations in basal conditions exert strong control on the discharge of outlet glaciers. Airborne and surface-based radar measurements of Beardmore Glacier will be made to map the ice thickness and geometry of the sub-glacial trough and active and passive seismic experiments, together with ground-based radar and GPS measurements will be made to map spatial and temporal variations of conditions at the ice-bed interface. The observational data will be used to constrain dynamic models of glacier flow. The models will be used to address the primary controls on the dynamics of Antarctic outlet glaciers, the conditions at the bed, their spatial and temporal variation, and how such variability might affect the sliding and flow of these glaciers. The work will also explore whether or not these outlet glaciers could draw down the interior of East Antarctica, and if so, how fast. The study will take three years including two field seasons to complete and results from the work will be disseminated through public and professional meetings and journal publications. All data and metadata will be made available through the NSIDC web portal. The broader impacts of the work are that it will help elucidate the fundamental physics of outlet glacier dynamics which is needed to improve predictions of the response of ice sheets to changing environmental conditions. The project will also provide support for early career investigators and will provide training and support for one graduate and two undergraduate students. All collaborators are currently involved in scientific outreach and graduate student education and they are committed to fostering diversity.
Timmerman/1341311 This award supports a project to study the physical processes that synchronize glacial-scale variability between the Northern Hemisphere ice sheets and the Antarctic ice-sheet. Using a coupled numerical ice-sheet earth-system model, the research team will explore the cryospheric responses to past changes in greenhouse gas concentrations and variations in earth's orbit and tilt. First capturing the sensitivity of each individual ice-sheet to these forcings and then determining their joint variability induced by changes in sea level, ocean temperatures and atmospheric circulation, the researchers will quantify the relative roles of local versus remote effects on long-term ice volume variability. The numerical experiments will provide deeper physical insights into the underlying dynamics of past Antarctic ice-volume changes and their contribution to global sea level. Output from the transient earth system model simulations will be directly compared with ice-core data from previous and ongoing drilling efforts, such as West Antarctic Ice Sheet (WAIS) Divide. Specific questions that will be addressed include: 1) Did the high-latitude Southern Hemispheric atmospheric and oceanic climate, relevant to Antarctic ice sheet forcing, respond to local insolation variations, CO2, Northern Hemispheric changes, or a combination thereof?; 2) How did WAIS and East Antarctic Ice Sheet (EAIS) vary through the Last Glacial Termination and into the Holocene (21 ka- present)?; 3) Did the WAIS (or EAIS) contribute to rapid sea-level fluctuations during this period, such as Meltwater Pulse 1A? 4) Did WAIS collapse fully at Stage 5e (~ 125 ka), and what was its timing relative to the maximum Greenland retreat?; and 5) How did the synchronized behavior of Northern Hemisphere and Southern Hemisphere ice-sheet variations affect the strength of North Atlantic Deep Water and Antarctic Bottom Water formation and the respective overturning cells? The transient earth-system model simulations conducted as part of this project will be closely compared with paleo-climate reconstructions from ice cores, sediment cores and terrestrial data. This will generate an integrated understanding of the hemispheric contributions of deglacial climate change, the origin of meltwater pulses, and potential thresholds in the coupled ice-sheet climate system in response to different types of forcings. A well-informed long-term societal response to sea level rise requires a detailed understanding of ice-sheet sensitivities to external forcing. The proposed research will strongly contribute to this task through numerical modeling and paleo-data analysis. The research team will make the resulting model simulations available on the web-based data server at the Asia Pacific Data Research Center (APDRC) to enable further analysis by the scientific community. As part of this project a female graduate student and a postdoctoral researcher will receive training in earth-system and ice-sheet modeling and paleo-climate dynamics. This award has no field work in Antarctica.
Ice-core records are critical to understanding past climate variations. An Antarctic ice core currently being drilled at the South Pole will allow detailed investigation of atmospheric gases and fill an important gap in understanding the pattern of climate variability across Antarctica. Critical to the interpretation of any ice core are: 1) accurate chronologies for both the ice and the trapped gas and 2) demonstration that records from the ice core reliably reflect climate. The proposed research will improve the ice and gas chronologies by making measurements of snow compaction in the upstream catchment in order to constrain age models of the ice. These measurements will be a key data set needed for better understanding and predicting time-varying conditions in the upper part of the ice sheet. The research team will measure the modern spatial gradients in accumulation rate, surface temperature, and water stable isotopes from shallow ice cores in the upstream catchment in order to determine the climate history from the ice-core record. The new ice-flow measurements will make it possible to define the path of ice from upstream to the South Pole ice-core drill site to assess spatial gradients in snowfall and to infer histories of snowfall from internal layers within the ice sheet. The project will be led by an early-career scientist, provide broad training to graduate students, and engage in public outreach on polar science. Ice-core records of stable isotopes, aerosol-born particles, and atmospheric gases are critical to understanding past climate variations. The proposed research will improve the ice and gas chronologies in the South Pole ice core by making in situ measurements of firn compaction in the upstream catchment to constrain models of the gas-age ice-age difference. The firn measurements will be a key data set needed to form a constitutive relationship for firn, and will drive better understanding and prediction of transient firn evolution. The research team will measure the modern gradients in accumulation rate, surface temperature, and water stable isotopes in the upstream catchment to separate spatial (advection) variations from temporal (climate) variations in the ice-core records. The ice-flow measurements will define the flowline upstream of the drill site, assess spatial gradients in accumulation, and infer histories of accumulation from radar-observed internal layers. Results will directly enhance interpretation of South Pole ice-core records, and also advance understanding of firn densification and drive next-generation firn models.
The Palmer Antarctica LTER (Long Term Ecological Research) site has been in operation since 1990. The goal of all the LTER sites is to conduct policy-relevant research on ecological questions that require tens of years of data, and cover large geographical areas. For the Palmer Antarctica LTER, the questions are centered around how the marine ecosystem west of the Antarctica peninsula is responding to a climate that is changing as rapidly as any place on the Earth. For example, satellite observations over the past 35 years indicate the average duration of sea ice cover is now ~90 days (3 months!) shorter than it was. The extended period of open water has implications for many aspects of ecosystem research, with the concurrent decrease of Adèlie penguins within this region regularly cited as an exemplar of climate change impacts in Antarctica. Cutting edge technologies such as autonomous underwater (and possibly airborne) vehicles, seafloor moorings, and numerical modeling, coupled with annual oceanographic cruises, and weekly environmental sampling, enables the Palmer Antarctica LTER to expand and bridge the time and space scales needed to assess climatic impacts. This award includes for the first time study of the roles of whales as major predators in the seasonal sea ice zone ecosystem. The team will also focus on submarine canyons, special regions of enhanced biological activity, along the Western Antarctic Peninsula (WAP). The current award's overarching research question is: How do seasonality, interannual variability, and long term trends in sea ice extent and duration influence the structure and dynamics of marine ecosystems and biogeochemical cycling? Specific foci within the broad question include: 1. Long-term change and ecosystem transitions. What is the sensitivity or resilience of the ecosystem to external perturbations as a function of the ecosystem state? 2. Lateral connectivity and vertical stratification. What are the effects of lateral transports of freshwater, heat and nutrients on local ocean stratification and productivity and how do they drive changes in the ecosystem? 3. Top-down controls and shifting baselines. How is the ecosystem responding to the cessation of whaling and subsequent long-term recovery of whale stocks? 4. Foodweb structure and biogeochemical processes. How do temporal and spatial variations in foodweb structure influence carbon and nutrient cycling, export, and storage? The broader impacts of the award leverage local educational partnerships including the Sandwich, MA STEM Academy, the New England Aquarium, and the NSF funded Polar Learning and Responding (PoLAR) Climate Change Education Partnership at Columbia's Earth Institute to build new synergies between Arctic and Antarctic, marine and terrestrial scientists and students, governments and NGOs. The Palmer Antarctic LTER will also conduct appropriate cross LTER site comparisons, and serve as a leader in information management to enable knowledge-building within and beyond the Antarctic, oceanographic, and LTER communities.
Ice cores record detailed histories of past climate variations. The South Pole ice core will allow investigation of atmospheric trace gases and fill an important gap in understanding the pattern of climate variability across Antarctica. An accurate timescale that assigns an age to the ice at each depth in the core is essential to interpretation of the ice-core records. This work will use electrical methods to identify volcanic eruptions throughout the past ~40,000 years in the core by detecting the enhanced electrical conductance in those layers due to volcanic impurities in the ice. These eruptions will be pattern-matched to other cores across Antarctica, synchronizing the timing of climate variations among cores and allowing the precise timescales developed for other Antarctic ice cores to be transferred to the South Pole ice core. The well-dated records of volcanic forcing will be combined with records of atmospheric gases, stable water-isotopes, and aerosols to better understand the large natural climate variations of the past 40,000 years. The electrical conductance method and dielectric profiling measurements will be made along the length of each section of the South Pole ice core at the National Ice Core Lab. These measurements will help to establish a timescale for the core. Electrical measurements will provide a continuous record of volcanic events for the entire core including through the brittle ice (550-1250m representing ~10,000-20,000 year-old ice) where the core quality and thin annual layers may prevent continuous melt analysis and cause discrete measurements to miss volcanic events. The electrical measurements also produce a 2-D image of the electrical layering on a longitudinal cut surface of each core. These data will be used to identify any irregular or absent layering that would indicate a stratigraphic disturbance in the core. A robust chronology is essential to interpretation of the paleoclimate records from the South Pole ice core. The investigators will engage teachers through talks and webinars with the National Science Teachers Association and will share information with the public at events such as Polar Science Weekend at the Pacific Science Center. Results will be disseminated through publications and conference presentations and the data will be archived and publicly available.
This award supports a project to use the Roosevelt Island ice core as a glaciological dipstick for the eastern Ross Sea. Recent attention has focused on the eastern Ross Embayment, where there are no geological constraints on ice thickness changes, due to the lack of protruding rock "dipsticks" where the ice sheet can leave datable records of high stands. Recent work has shown how dated ice cores can be used as dipsticks to derive ice-thickness histories. Partners from New Zealand and Denmark will extract an ice core from Roosevelt Island during the 2010-2011 and 2011-12 austral summers. Their science objective is to contribute to understanding of climate variability over the past 40kyr. The science goal of this project is not the climate record, but rather the history of deglaciation in the Ross Sea. The new history from the eastern Ross Sea will be combined with the glacial histories from the central Ross Sea (Siple Dome and Byrd) and existing and emerging histories from geologic and marine records along the western Ross Sea margin and will allow investigators to establish an updated, self-consistent model of the configuration and thickness of ice in the Ross Embayment during the LGM, and the timing of deglaciation. Results from this work will provide ground truth for new-generation ice-sheet models that incorporate ice streams and fast-flow dynamics. Realistic ice-sheet models are needed not only for predicting the response to future possible environments, but also for investigating past behaviors of ice sheets. This research contributes to the primary goals of the West Antarctic Ice Sheet Initiative as well as the IPY focus on ice-sheet history and dynamics. It also contributes to understanding spatial and temporal patterns of climate change and climate dynamics over the past 40kyr, one of the primary goals of the International Partnerships in Ice Core Sciences (IPICS). The project will help to develop the next generation of scientists and will contribute to the education and training of two Ph.D. students. All participants will benefit from the international collaboration, which will expose them to different field and laboratory techniques and benefit future collaborative work. All participants are involved in scientific outreach and undergraduate education, and are committed to fostering diversity. Outreach will be accomplished through regularly scheduled community and K-12 outreach events, talks and popular writing by the PIs, as well as through University press offices.
Like no other region on Earth, the northern Antarctic Peninsula represents a spectacular natural laboratory of climate change and provides the opportunity to study the record of past climate and ecological shifts alongside the present-day changes in one of the most rapidly warming regions on Earth. This award supports the cryospheric and oceano-graphic components of an integrated multi-disciplinary program to address these rapid and fundamental changes now taking place in Antarctic Peninsula (AP). By making use of a marine research platform (the RV NB Palmer and on-board helicopters) and additional logistical support from the Argentine Antarctic program, the project will bring glaciologists, oceanographers, marine geologists and biologists together, working collaboratively to address fundamentally interdisciplinary questions regarding climate change. The project will include gathering a new, high-resolution paleoclimate record from the Bruce Plateau of Graham Land, and using it to compare Holocene- and possibly glacial-epoch climate to the modern period; investigating the stability of the remaining Larsen Ice Shelf and rapid post-breakup glacier response ? in particular, the roles of surface melt and ice-ocean interactions in the speed-up and retreat; observing the contribution of, and response of, oceanographic systems to ice shelf disintegration and ice-glacier interactions. Helicopter support on board will allow access to a wide range of glacial and geological areas of interest adjacent to the Larsen embayment. At these locations, long-term in situ glacial monitoring, isostatic uplift, and ice flow GPS sites will be established, and high-resolution ice core records will be obtained using previously tested lightweight drilling equipment. Long-term monitoring of deep water outflow will, for the first time, be integrated into changes in ice shelf extent and thickness, bottom water formation, and multi-level circulation by linking near-source observations to distal sites of concentrated outflow. The broader impacts of this international, multidisciplinary effort are that it will significantly advance our understanding of linkages amongst the earth's systems in the Polar Regions, and are proposed with international participation (UK, Spain, Belgium, Germany and Argentina) and interdisciplinary engagement in the true spirit of the International Polar Year (IPY). It will also provide a means of engaging and educating the public in virtually all aspects of polar science and the effects of ongoing climate change. The research team has a long record of involving undergraduates in research, educating high-performing graduate students, and providing innovative and engaging outreach products to the K-12 education and public media forums. Moreover, forging the new links both in science and international Antarctic programs will provide a continuing legacy, beyond IPY, of improved understanding and cooperation in Antarctica.
Intellectual Merit: The PIs propose to complement the ANDRILL marine record with a terrestrial project that will provide chronological control for past fluctuations of the West Antarctic Ice Sheet (WAIS) and alpine glaciers in McMurdo Sound. The project will develop high-resolution maps of drifts deposited from grounded marine-based ice and alpine glaciers on islands and peninsulas in McMurdo Sound. In addition, the PIs will acquire multi-clast/multi-nuclide cosmogenic analyses of these mapped drift sheets and alpine moraines and use regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession. The PIs will make use of geological records for ice sheet and alpine glacier fluctuations preserved on the flanks of Mount Discovery, Black Island, and Brown Peninsula. Drifts deposited from grounded, marine-based ice will yield spatial constraints for former advances and retreats of the WAIS. Moraines from alpine glaciers, hypothesized to be of interglacial origin, could yield a first-order record of hydrologic change in the region. Synthesizing the field data, the team proposes to improve the resolution of existing regional-scale climate models for the Ross Embayment. The overall approach and anticipated results will provide the first steps towards linking the marine and terrestrial records in this critical sector of Antarctica. Broader impacts: Results from the proposed work will be integrated with outreach programs at Boston University, Columbia University, and Worcester State University. The team will actively collaborate with the American Museum of Natural History to feature this project prominently in museum outreach. The team will also include a PolarTREC teacher as a member of the research team. The geomorphological results will be presented in 3D at Boston University?s Antarctic Digital Image Analyses Lab. The research will form the basis of a PhD dissertation at Boston University.
Interest in the reduced alkalinity of high latitude waters under conditions of enhanced CO2 uptake from the atmosphere have been the impetus of numerous recent studies of bio-stressors in the polar marine environment. The project seeks to improve our understanding of the variance of coastal Southern Ocean carbonate species (CO2 system), its diurnal and inter-annual variability, by acquiring autonomous, high frequency observations from an Antarctic coastal mooring(s). A moored observing system co-located within the existing Palmer LTER array will measure pH, CO2 partial pressure, temperature, salinity and dissolved oxygen with 3-hour frequency in this region of the West Antarctic Peninsula continental shelf. Such observations will help estimate the dominant physical and biological controls on the seasonal variations in the CO2 system in coastal Antarctic waters, including the sign, seasonality and the flux of the net annual air-sea exchange of carbon dioxide. The Palmer LTER site is experiencing rapid ecological change in the West Antarctic Peninsula, a region that is warming at rates faster than any other region of coastal Antarctica.
Antarctic clouds constitute an important parameter of the surface radiation budget and thus play a significant role in Antarctic climate and climate change. The variability in, and long term trends of, cloud optical and microphysical properties are therefore fundamental in parameterizing the mixed phase (water-snow-ice) coastal Antarctic stratiform clouds experienced around the continent. Using a spectoradiometer that covers the wavelength range of 350 to 2200nm, the downwelled spectral irradiance at the earth surface (Ross Island) will be used to retrieve the optical depth, thermodynamic phase, liquid water droplet effective radius, and ice-cloud effective particle size of overhead clouds, at hourly intervals and for an austral summer season (Oct-March). Based on the very limited data sets that exist for the maritime Antarctic, expectations are that Ross Island (Lat 78 S) should exhibit clouds with: a) An abundance of supercooled liquid water, and related mixed-phase cloud processes b) Cloud nucleation from year round biogenic and oceanic sources, in an otherwise pristine environment c) Simple cloud geometries of predominantly stratiform cloud decks Increased understanding of the cloud properties in the region of the main USAP base, McMurdo station is also relevant to operational weather forecasting relevant to aviation. A range of educational and outreach activities are associate with the project, including provision of workshops for high school teachers will be carried out.
The investigators will map glacial deposits and date variations in glacier variability at several ice-free regions in northern Victoria Land, Antarctica. These data will constrain the nature and timing of past ice thickness changes for major glaciers that drain into the northwestern Ross Sea. This is important because during the Last Glacial Maximum (15,000 - 18,000 years ago) these glaciers were most likely flowing together with grounded ice from both the East and West Antarctic Ice Sheets that expanded across the Ross Sea continental shelf to near the present shelf edge. Thus, the thickness of these glaciers was most likely controlled in part by the extent and thickness of the Ross Sea ice sheet and ice shelf. The data the PIs propose to collect can provide constraints on the position of the grounding line in the western Ross Sea during the Last Glacial Maximum, the time that position was reached, and ice thickness changes that occurred after that time. The primary intellectual merit of this project will be to improve understanding of a period of Antarctic ice sheet history that is relatively unconstrained at present and also potentially important in understanding past ice sheet-sea level interactions. This proposal will support an early career researcher's ongoing program of undergraduate education and research that is building a socio-economically diverse student body with students from backgrounds underrepresented in the geosciences. This proposal will also bring an early career researcher into Antarctic research.
Paragraph for Laypersons: This research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations. Paragraph for Scientific Community: Rock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure dating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.
Alley/1142085 This award supports a project to continue the collection and analyses of firn temperature data from three automated firn thermal profiling units deployed in Dronning Maud Land sector of East Antarctica as part of the Norway-US IPY Traverse project between 2007 and 2009. The intellectual merits of this project are as follows: 1) to constrain and improve the parameterization of firn thermal properties (thermal conductivity and specific heat capacity) that are required for the borehole paleothermometry, 2) to study the change in firn temperature since the deployment of thermal profiling units ~5 years ago and derive the surface temperature trend for that time period, and 3) to compare and contrast the surface temperatures and their trends derived from the measured firn temperatures and satellite thermal infrared data for the past three decades. The project also involves acquiring and deploying an automated system to record transient temperatures at multiple depths in the top 16 meters of the shallow borehole at Dome Fuji, to provide useful data and to prepare for the possibility of conducting temperature-logging in the existing deep (3035 m) and shallow (112 m) boreholes at Dome Fuji in the near future. The preparation of the shallow borehole and the installation of the automated system will be carried out by collaborators from the Japanese Antarctic Research Expedition (JARE) in 2012-13 Antarctic field season. The data collected by this automated system will be used to constrain the thermal properties of upper firn layer at Dome Fuji, as well as comparing with data from other sites, increasing the geographic extent of these studies. The broader impacts of the project include presentation of results at scientific conferences and publication of results in peer-reviewed journals. Public outreach will include targeted work with science teachers and middle school students.
Antarctic Bottom Water (AABW) formation is a key component in setting the global thermohaline (overturning) circulation. Recent studies infer a reduction of the AABW component from reduced volume of AABW entering global deep ocean basins around the Antarctic continent. It is important to obtain better estimates of AABW production rate in its source areas, and to investigate whether the global overturning circulation is slowing down. The project will continue fieldwork with CTD/LADCP surveys including 2 yearly repeat sections, mooring recoveries and deployments. Seasonal-interannual variability of CDW intrusion, dense shelf water accumulation and export as well as overflow from the Prydz Bay shelf will also be observed. The Prydz Bay- Amery Ice Shelf region has been suggested as a key AABW production site. USAP access to this remote region of the Antarctic continent is challenging. The project will involve fieldwork to be carried out with Danish and Chinese collaboration aboard the Chinese research vessel, Xue Long. A high-resolution regional ocean-sea ice coupled model will be developed to allow time and space continuous three-dimensional ocean state estimation. Both in-situ and remote sensing observations along with the modeling simulation results will be used to investigate (i) the local atmosphere-ocean-sea ice interaction and shelf processes that produce dense shelf water and (ii) the dynamic processes that control the shelf water export.
Steig/1341360 This award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.
Marine paleoclimate archives show that approximately one million years ago Earth's climate transitioned from 40,000-year glacial /interglacial cycles to 100,000-year cycles. This award will support a study designed to map the distribution of one million year-old ice in the Allan Hills Blue Ice Area, Antarctica using state-of-the-art ground penetrating radar. The Allen Hills was demonstrated to contain a continuous record of the past 400,000 years and is also the collection location of the oldest ice samples (990,000 years) yet recovered. The maps resulting from this study will be used to select an ice-core drilling site at which a million-plus year-old continuous record of climate could be recovered. Ice cores contain the only kind of record to directly capture atmospheric gases and aerosols, but no ice-core-based climate record yet extends continuously beyond the past 800,000 years. A million-plus year-old record will allow better understanding of the major mechanisms and driving forces of natural climate variability in a world with 100,000-year glacial/interglacial cycles. The project will support two early career scientists in collaboration with senior scientists, as well as a graduate student, and will conduct outreach to schools and the public. The Allan Hills Blue Ice Area preserves a continuous climate record covering the last 400,000 years along an established glaciological flow line. Two kilometers to the east of this flow line, the oldest ice on Earth (~1 million years old) is found only 120 m below the surface. Meteorites collected in the area are reported to be as old as 1.8 million years, suggesting still older ice may be present. Combined, these data strongly suggest that the Allen Hills area could contain a continuous, well-resolved environmental record, spanning at least the last million years. As such, this area has been selected as an upcoming target for the new Intermediate Depth Ice Core Drill by the US Ice Core Working Group. This drill will recover a higher-quality core than previous dry drilling attempts. This project will conduct a comprehensive ground penetrating radar survey aimed at tracing the signature of the million-year-old ice layer throughout the region. The resulting map will be used to select a drill site from which an ice core containing the million-plus year-old continuous climate record will be collected. The proposed activities are a necessary precursor to the collection of the oldest known ice on Earth. Ice cores provide a robust reconstruction of past climate and extending this record beyond the 800,000 years currently available will open new opportunities to study the climate system. The data collected will also be used to investigate the bedrock and ice flow parameters favorable to the preservation of old ice, which may allow targeted investigation of other blue ice areas in Antarctica.
Hastings/1246223 This award supports a project with the aim of distinguishing the sources of nitrate deposition to the West Antarctic Ice Sheet (WAIS) using isotopic ratios snow in archive snow and ice samples. The isotopic composition of nitrate has been shown to contain information about the source of the nitrate (i.e. nitrogen oxides = NOx = NO+NO2) and the oxidation processes that convert NOx to nitrate in the atmosphere prior to deposition. A difficulty in interpreting records in the context of NOx sources is that nitrate can be post-depositionally processed in surface snow, such that the archived record does not reflect the composition of the atmosphere. This intellectual merit of this work specifically aims to investigate variability in the isotopic composition of nitrate in snow and ice from the WAIS in the context of accumulation rate, NOx source emissions, and atmospheric chemistry. These records will be interpreted in the context of our understanding of biospheric (biomass burning, microbial processes in soils), atmospheric (lightning, transport, chemistry), and climate (temperature, accumulation rate) changes over time. A graduate student will be supported as part of this project, and both graduate student and PI will be involved in communicating the utility and results of polar research to elementary school students in the Providence, RI area. The broader impacts of the project also include making efforts to attract more young, female scientists to polar research by establishing a connection between the Earth Science Women's Network (ESWN), an organization PI Hastings helped to establish, and the Association of Polar Early Career Scientists (APECS). Finally, results of all measurements will be presented at relevant conferences, made available publicly and published in peer-reviewed journals.
0538520<br/>Thiemens<br/>This award supports a project to develop the first complete record of multiple isotope ratios of nitrate and sulfate covering the last ~100,000 years, from the deep ice core planned for the central ice divide of the West Antarctic Ice Sheet (WAIS). The WAIS Divide ice core will be the highest resolution long ice core obtained from Antarctica and we can expect important complementary information to be available, including accurate knowledge of past accumulation rates, temperatures, and compounds such as H2O2, CO and CH4. These compounds play significant roles in global atmospheric chemistry and climate. Especially great potential lies in the use of multiple isotope signatures. The unique mass independent fractionation (MIF) 17O signature of ozone is observed in both nitrate and sulfate, due to the interaction of their precursors with ozone. The development of methods to measure the multiple-isotope composition of small samples of sulfate and nitrate makes continuous high resolution measurements on ice cores feasible for the first time. Recent work has shown that such measurements can be used to determine the hydroxyl radial (OH) and ozone (O3) concentrations in the paleoatmosphere as well as to apportion sulfate and nitrate sources. There is also considerable potential in using these isotope measurements to quantify post depositional changes. In the first two years, continuous measurements from the upper ~100-m of ice at WAIS divide will be obtained, to provide a detailed look at seasonal through centennial scale variability. In the third year, measurements will be made throughout the available depth of the deep core (expected to reach ~500 m at this time). The broader impacts of the project include applications to diverse fields including atmospheric chemistry, glaciology, meteorology, and paleoclimatology. Because nitrate and sulfate are important atmospheric pollutants, the results will also have direct and relevance to global environmental policy. This project will coincide with the International Polar Year (2007-2008), and contributes to goals of the IPY, which include the fostering of interdisciplinary research toward enhanced understanding of atmospheric chemistry and climate in the polar regions.
A 50+ year warming trend in the Southern Ocean has been most dramatic in Drake Passage and likely impacts ecosystem structure here. Acoustic Doppler Current Profiler (ADCP) records from multiple ?L.M. Gould? supply transits of Drake Passage from 1999 to present demonstrate spatial and temporal variability in acoustics backscattering. Acoustics backscattering strength in the upper water column corresponds to zooplankton and nekton biomass that supports predator populations. However, for much of Drake Passage the identity of taxa contributing to this acoustically detected biomass is not known. This project would introduce a biological component to ?L.M. Gould? transits of Drake Passage with the goal of determining the identity of taxa responsible for the backscattering records obtained by ADCP and relating these to higher trophic levels (seabird/marine mammal). Net sampling during spring, summer and fall transits will permit assessment of diel and seasonal changes in the abundance and taxonomic composition of zooplankton and top predators represented between Patagonia and the Antarctic Peninsula. Net samples and depth-referenced video records taken in conjunction with ADCP profiles will permit the identification of the dominant acoustic backscatters in the 3 biogeographic regions represented here, the Subantarctic, Polar Frontal, and Antarctic Zones. The validity of dominant backscattering taxa in the Antarctic Zone will be tested by comparing the ADCP records with abundant zooplankton data collected off the Antarctic Peninsula during January-March 1999-2009 as well with long-term top predator surveys. The broader impacts also include a cruise blog, the production of an article for an online outreach publication based at Moss Landing Marine Labs and a YouTube video featuring shipboard research in the Southern Ocean.
Intellectual Merit: The PI proposes an investigation of mantle xenoliths entrained within a suite of ~1.4 Ma mafic volcanic centers in the Fosdick Mountains, Antarctica. These recently entrained mantle xenoliths offer a unique opportunity to characterize the West Antarctic lithospheric mantle that has been subject to active modification from Cretaceous to Present by plate-boundary processes, such as orthogonal to oblique plate convergence, intracontinental rifting, continental breakup, and Neogene volcanism. These volcanic centers derive from heterogeneous mantle sources and host a compositionally diverse suite of mantle xenoliths that have varied mineral assemblages and microstructures. The proposed research has two complementary goals: to assess structural and compositional heterogeneity within the upper mantle and the variability of intrinsic and extrinsic variables at a variety of lithospheric levels; and to use textural and compositional characterization of the xenolith suite to elucidate possible causes of heterogeneous seismic anisotropy within the Marie Byrd Land mantle lithosphere and inform competing hypotheses explaining the active volcanism, thermal anomaly, and slow seismic velocities beneath West Antarctica. Furthermore, characterization of samples of the mantle beneath West Antarctica provides a type of 'ground truth' in support of contemporary ANET/POLENET seismology research that seeks to determine mantle composition, temperature, and sources of seismic anisotropy. Broader impacts: The PI is in his first-year as a tenure track faculty member at Boston College. A postdoctoral researcher will be trained in EBSD techniques, interdisciplinary polar research, and the mentoring of undergraduate investigators. Two Boston College undergraduates will participate in the research and a priority will be placed on selecting underrepresented minorities and first-generation college students. An existing sample suite assembled over more than 20 years of NSF sponsored field work, will be used. The PI will create a digital database for microstructural, textural, and xenolith data for rapid dissemination to the international Antarctic community.
The research supported in this project will examine the effects of environmental change on a key Antarctic marine invertebrate, a pelagic mollusk, the pteropod, Limacina helicina antarctica. There are two main activities in this project: (1) to deploy oceanographic equipment ? in this case, autonomously recording pH sensors called SeaFETs and other devices that record temperature and salinity, and (2) to use these environmental data in the laboratory at McMurdo Station to study the response of the marine invertebrates to future changes in water quality that is expected in the next few decades. Notably, changes in oceanic pH (aka ocean acidification) and ocean warming are projected to be particularly threatening to calcifying marine organisms in cold-water, high latitude seas, making tolerance data on these organisms a critical research need in Antarctic marine ecosystems. These Antarctic shelled-animals are especially vulnerable to dissolution stress from ocean acidification because they currently inhabit seawater that is barely at the saturation level to support biogenic calcification. Indeed, these polar animals are considered to be the 'first responders' to chemical changes in the surface oceans. Thus, this project will lead to information about the adaptive capacity of L. helcina antarctica. From an ecological perspective this is important because this animal is a critical part of the Antarctic food chain in coastal waters and changes in its abundance will impact other species. Finally, the research conducted in this project will serve as a training and educational opportunity for undergraduate and graduate students as well as postdoctoral scholars.
Intellectual Merit: <br/>This proposal will study the diversity, abundance, and tiering patterns of ichnofossils in continental and marine deposits of the Beacon Supergroup in the Beardmore Glacier Area (BGA). The PIs will focus on continental strata that contain a variety of ichnofossils and paleosols. Ichnofossils will be evaluated for their architectural and surficial morphologies, and will be compared to modern and ancient traces to interpret the tracemaker behavior and paleoenvironmental setting. Distribution of ichnofossils within these units may indicate the effect of lateral variability of pedogenesis, the magnitude and frequency of depositional events, and the amount of moisture within the sediment, as well as the effects of climate change. The paleoclimatic significance of ichnofossils will be determined by comparing the burrow size, occurrence, tiering, and pedogenic significance of ichnofossils in measured sections of stratigraphic units deposited during global warming and cooling episodes. Comparisons will be made between BGA formations to stratigraphically equivalent rocks deposited at low paleolatitudes with previously determined paleoclimatic settings. The objectives of this project are to address two major questions: what differences existed in ichnodiversity, abundance, and tiering in marine and continental deposits between high- and low-paleolatitudes, and was there a dearth of habitat usage in continental deposits during the late Paleozoic and Mesozoic, particularly in fluvial and lacustrine environments compared to the habitat usage in the marine realm at that time? <br/><br/>Broader impacts: <br/>This study will enhance the ability to interpret paleoenvironments to the subenvironmental scale, understand the evolution of soil biota and ecosystems at high paleolatitudes, determine the role of organisms in soil formation at high paleolatitudes, explore the effects of climate change on the body size and diversity of organisms in the soil communities, and develop new tools to interpret paleoclimate in high latitudes. There is a strong education component associated with this proposal.
1043750/Chen This award supports a project to improve the estimate of long-term and inter-annual variability of Antarctic ice sheet mass balance at continental, regional, and catchment scales, using satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) and other geodetic measurements. The work will improve the quantification of long-term mass change rates over Antarctica using GRACE gravity data with a longer record and newer generation(s) of products and will develop advanced numerical forward modeling techniques that can accurately correct leakage effects associated with GRACE data processing, and significantly improve spatial resolution of GRACE mass rate estimates over Antarctica. The work will also contribute to a better understanding of crustal uplift rates due to postglacial rebound (PGR) and present day ice load change over Antarctica via PGR models, GPS measurements, and combined analysis of GRACE and ICESat elevation changes. Inter-annual variations of ice mass over Antarctica will be investigated at continental and catchment scales and connections to regional climate change will be studied. The major deliverables from this study will be improved assessments of ice mass balance for the entire Antarctic ice sheet and potential contribution to global mean sea level rise. The work will also provide estimates of regional ice mass change rates over Antarctica, with a focus along the coast in the Amundsen Sea Embayment, the Peninsula in West Antarctica, and in Wilkes Land and Victoria Land in East Antarctica. Estimates of inter-annual ice mass change over Antarctica at various spatial scales, and assessments of uncertainty of GRACE ice rate estimates and PGR models errors over Antarctica will also be made. The intellectual merits of the proposed investigation include 1) providing improved assessments of Antarctic ice mass balance at different temporal and spatial scales with unprecedented accuracy, an important contribution to broad areas of polar science research; 2) combining high accuracy GPS vertical uplift measurements and PGR models to better quantify long-term crust uplift effects that are not distinguishable from ice mass changes by GRACE; and 3) unifying the work of several investigations at the forefront of quantifying ice sheet and glacier mass balance and crustal uplift based on a variety of modern space geodetic observations. The broader impacts include the fact that the project will actively involve student participation and training, through the support of two graduate students. In addition the project will contribute to general education and public outreach (E/PO) activities and the results from this investigation will help inspire future geoscientists and promote public awareness of significant manifestations of climate change.
Abstract The Erebus Bay population of Weddell seals in Antarctica?s Ross Sea is the most southerly breeding population of mammal in the world, closely associated with persistent shore-fast ice, and one that has been intensively studied since 1968. The resulting long-term database, which includes data for 20,586 marked individuals, contains detailed population information that provides an excellent opportunity to study linkages between environmental conditions and demographic processes in the Antarctic. The population?s location is of special interest as the Ross Sea is one of the most productive areas of the Southern Ocean, one of the few pristine marine environments remaining on the planet, and, in contrast to the Antarctic Peninsula and Arctic, is undergoing a gradual lengthening of the sea-ice season. The work to be continued here capitalizes on (1) long-term data for individual seals and their polar environment; (2) experience collecting and analyzing data from the extensive study population; and (3) recent statistical advances in hierarchical modeling that allow for rigorous treatment of individual heterogeneity (in mark-recapture and body mass data) and inclusion of diverse covariates hypothesized to explain variation in fitness components. Covariates to be considered include traits of individuals and their mothers and environmental conditions throughout life. The study will continue to (1) provide detailed data on known-age individuals to other science projects and (2) educate and mentor the next generation of ecologists through academic and professional training and research experiences.
Pettit/0948247<br/><br/>This award supports a project to study of the relationship between fabric and climate for the ice near the EPICA Dome C ice core site, East Antarctica. The work builds on an ongoing study at Siple Dome, West Antarctica and takes advantage of collaborations with European scientists and access to the Dome C borehole to make measurements of sonic velocity. The intellectual merit of the project is that a better understanding of how fabric preserves past climate information can improve models of the ice flow near ice core sites and the interpreta-tion of ice core data (particularly paleo-accumulation), and it may allow us to extract climate information directly from fabric data. In addition, because ice deformation is sensitive to the orientation of crystals, ice flow patterns are sensitive to the fabric. Thus, variations in the fabric between glacial and interglacial ice can affect how ice deforms and how fabric in the ice sheet develops. The Dome C site is particularly important for answering these questions, because the ice core shows evidence of eight glacial cycles, not just one as found at Siple Dome or the Greenland sites. The research will improve the understanding of the proxy relationship between sonic-velocity data and fabric; will help to model the pattern of ice flow caused by the fabric variation between glacial and interglacial time periods using these data, existing ice core chemistry and existing and new thin section data, improved surface strain data, and borehole deformation data; and will help to better understand the positive feedback mechanism that enhances fabric (and corresponding rheological) variability through a focused study of several climate transitions and the associated fabric changes. Borehole compressional-wave sonic-velocity will be measured which will complement the sonic-velocity data that already exist for boreholes in Greenland and West Antarctica. These will be the first sonic-velocity measurements in East Antarctica and the first measurements that extend for more than a single glacial/interglacial transition. The project will ultimately contribute to better interpretation of ice core records for both paleoclimate studies and for ice flow history, both of which connect to the broader questions of the role of ice in the climate system. This project will also strengthen the international collaborations within the paleoclimate and ice sheet modeling communities. This project will partially support a graduate student at the University of Alaska Fairbanks who is currently working on modeling ice including anisotropy and it will support the growth of a young scientist through a Post-Doc position. This Post Doc will gain important experience collaborating with the EPICA scientists in studying the climate-fabric relationship. Erin Pettit is active in field-science education for high school students, under-graduates, teachers, and adults. This project will help support the continued development and enhancement of Girls on Ice a program that encourages young women to explore science and the natural world.
Intellectual Merit: Knowledge of englacial and subglacial conditions are critical for ice sheet models and predictions of sea-level change. Some of the critical variables that are poorly known but essential for improving flow models and predictions of sea-level change are: basal roughness, subglacial sedimentary and hydrologic conditions, and the temporal and spatial variability of the ice sheet flow field. Seismic reflection and refraction imaging and dense arrays of continuously operating GPS receivers can determine these parameters. The PIs propose to develop a network of wirelessly interconnected geophysical sensors (geoPebble) that will allow glaciologists to carry out these experiments simultaneously. This sensor web will provide a new way of imaging the ice sheet that is not possible with current instruments. With this sensor web, the PIs will extend the range of existing instruments from 2D to 3D, from low resolution to high resolution, but more importantly, all the geophysical measurements will be conducted synchronously. By the end of the proposal period the PIs will produce a network of 150-200 geoPebbles that will be available for NSF-sponsored glaciology research projects. Broader impacts: Improved knowledge of the flow law of ice, the sliding of glaciers and ice streams, and paleoclimate history will contribute to assessments of the potential for abrupt ice-sheet mass change, with consequent sea-level effects and significant societal impacts. This improved modeling ability will be a direct consequence of better knowledge of the physical properties of ice sheets, which this project will facilitate. The development effort will be integrated with the undergraduate education program via the capstone design classes in EE and the senior thesis requirement in Geoscience. The PIs will also form a cohort of first-year and sophomore students who will work in their labs from the beginning of the project to develop specifications through the commissioning of the network.
This award supports a project to broaden the knowledge of annual accumulation patterns over the West Antarctic Ice Sheet by processing existing near-surface radar data taken on the US ITASE traverse in 2000 and by gathering and validating new ultra/super-high-frequency (UHF) radar images of near surface layers (to depths of ~15 m), expanding abilities to monitor recent annual accumulation patterns from point source ice cores to radar lines. Shallow (15 m) ice cores will be collected in conjunction with UHF radar images to confirm that radar echoed returns correspond with annual layers, and/or sub-annual density changes in the near-surface snow, as determined from ice core stable isotopes. This project will additionally improve accumulation monitoring from space-borne instruments by comparing the spatial-radar-derived-annual accumulation time series to the passive microwave time series dating back over 3 decades and covering most of Antarctica. The intellectual merit of this project is that mapping the spatial and temporal variations in accumulation rates over the Antarctic ice sheet is essential for understanding ice sheet responses to climate forcing. Antarctic precipitation rate is projected to increase up to 20% in the coming century from the predicted warming. Accumulation is a key component for determining ice sheet mass balance and, hence, sea level rise, yet our ability to measure annual accumulation variability over the past 5 decades (satellite era) is mostly limited to point-source ice cores. Developing a radar and ice core derived annual accumulation dataset will provide validation data for space-born remote sensing algorithms, climate models and, additionally, establish accumulation trends. The broader impacts of the project are that it will advance discovery and understanding within the climatology, glaciology and remote sensing communities by verifying the use of UHF radars to monitor annual layers as determined by visual, chemical and isotopic analysis from corresponding shallow ice cores and will provide a dataset of annual to near-annual accumulation measurements over the past ~5 decades across WAIS divide from existing radar data and proposed radar data. By determining if temporal changes in the passive microwave signal are correlated with temporal changes in accumulation will help assess the utility of passive microwave remote sensing to monitor accumulation rates over ice sheets for future decades. The project will promote teaching, training and learning, and increase representation of underrepresented groups by becoming involved in the NASA History of Winter project and Thermochron Mission and by providing K-12 teachers with training to monitor snow accumulation and temperature here in the US, linking polar research to the student?s backyard. The project will train both undergraduate and graduate students in polar research and will encouraging young investigators to become involved in careers in science. In particular, two REU students will participate in original research projects as part of this larger project, from development of a hypothesis to presentation and publication of the results. The support of a new, young woman scientist will help to increase gender diversity in polar research.
Aydin/1043780 This award supports the analysis of the trace gas carbonyl sulfide (COS) in a deep ice core from West Antarctic Ice Sheet Divide (WAIS-D), Antarctica. COS is the most abundant sulfur gas in the troposphere and a precursor of stratospheric sulfate. It has a large terrestrial COS sink that is tightly coupled to the photosynthetic uptake of atmospheric carbon dioxide (CO2). The primary goal of this project is to develop high a resolution Holocene record of COS from the WAIS-D 06A ice core. The main objectives are 1) to assess the natural variability of COS and the extent to which its atmospheric variability was influenced by climate variability, and 2) to examine the relationship between changes in atmospheric COS and CO2. This project also includes low-resolution sampling and analysis of COS from 10,000-30,000 yrs BP, covering the transition from the Last Glacial Maximum into the early Holocene. The goal of this work is to assess the stability of COS in ice core air over long time scales and to establish the COS levels during the last glacial maximum and the magnitude of the change between glacial and interglacial conditions. The results of this work will be disseminated via peer-review publications and will contribute to environmental assessments such as the WMO Stratospheric Ozone Assessment and IPCC Climate Assessment. This project will support a PhD student and undergraduate researcher in the Department of Earth System Science at the University of California, Irvine, and will create summer research opportunities for undergraduates from non-research active Universities.
The Office of Polar Programs, Antarctic Science Division, Ocean & Climate Systems Program has made this award to support a multidisciplinary effort to study the upwelling of relatively warm deep water onto the Amundsen Sea continental shelf and how it relates to atmospheric forcing and bottom bathymetry and how the warm waters interact with both glacial and sea ice. This study constitutes a contribution of a coordinated research effort in the region known as the Amundsen Sea Embayment Project or ASEP. Previous work by the PI and others has shown that the West Antarctic Ice Sheet has been found to be melting faster, perhaps by orders of magnitude, than ice sheets elsewhere around Antarctica, excluding those on the Peninsula. Submarine channels that incise the continental shelf are thought to provide fairly direct access of relatively warm circum polar deep water to the cavity under the floating extension of the ice shelf. Interactions with sea ice en route can modify the upwelled waters. The proposed investigations build on previous efforts by the PI and colleagues to use hydrographic measurements to put quantitative bounds on the rate of glacial ice melt by relatively warm seawater. <br/>The region can be quite difficult to access due to sea ice conditions and previous hydrographic measurements have been restricted to the austral summer time frame. In this project it was proposed to obtain the first austral spring hydrographic data via CTD casts and XBT drops (September-October 2007) as part of a separately funded cruise (PI Steve Ackley) the primary focus of which is sea-ice conditions to be studied while the RV Nathanial B Palmer (RV NBP) drifts in the ice pack. This includes opportunistic sampling for pCO2 and TCO2. A dedicated cruise in austral summer 2009 will follow this opportunity. The principal objectives of the dedicated field program are to deploy a set of moorings with which to characterize temporal variability in warm water intrusions onto the shelf and to conduct repeat hydrographic surveying and swath mapping in targeted areas, ice conditions permitting. Automatic weather stations are to be deployed in concert with the program, sea-ice observations will be undertaken from the vessel and the marine cavity beneath the Pine Island may be explored pending availability of the British autonomous underwater vehicle Autosub 3. These combined ocean-sea ice-atmosphere observations are aimed at a range of model validations. A well-defined plan for making data available as well as archiving in a timely fashion should facilitate a variety of modeling efforts and so extend the value of the spatially limited observations. <br/>Broader impacts: This project is relevant to an International Polar Year research emphasis on ice sheet dynamics focusing in particular on the seaward ocean-ice sheet interactions. Such interactions must be clarified for understanding the potential for sea level rise by melt of the West Antarctic ice Sheet. The project entails substantive international partnerships (British Antarctic Survey and Alfred Wegner Institute) and complements other Amundsen Sea Embayment Project proposals covering other elements of ice sheet dynamics. The proposal includes partial support for 2 graduate students and 2 post docs. Participants from the Antarctic Artists and Writers program are to take part in the cruise and so aid in outreach. In addition, the project is to be represented in the Lamont-Doherty annual open house.
1245659/Petrenko This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, δ18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, δ13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of δ13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.
Time series data, from ocean moorings, on key aspects of evolving ocean properties are of considerable importance in assessing the condition of the ocean system. They are needed, for example, their understand how the oceans are warming, and how they continue to uptake greenhouse gases such as CO2. The Cape Adare Long Term Mooring (CALM) program goal was to observe the bottom water export from the Ross Sea to the deep ocean. To accomplish this two instrumented moorings were set on the continental slope off Cape Adare (western Ross Sea, Antarctica), positioned to capture the export of Antarctic Bottom Water (AABW), some of the coldest and densest water found in the global ocean. Data records for the moorings spans over some four years in this very remote part of the ocean. The CALM analysis will address some specific objectives: ? Characterize the temperature, salinity and current variability associated with the Ross Sea AABW export. ? Examine the linkages between observed variability to regional tides, atmosphere and sea ice forcing. ? Relate the Ross Sea AABW export fluctuations to the larger scale climate system dynamics, such as ENSO and SAM, and to AABW formation along other margins of Antarctica, e.g. the Weddell Sea
Abstract Researchers will explore the use of a distributed temperature sensing monitoring system (DTS), using fiber-optical (FO) technology, as the basis of a sustainable, sub-ice cavity sensing array. FO cable systems, such as may be deployed through a hot-water drilled hole through an ice shelf, passing through the underlying cavity to the sea floor, are capable of measuring temperatures down fiber at 1 meter intervals, and at time frequencies as high as 15 seconds. DTS FO systems operate via optical time domain reflectometry along the fiber waveguide using inelastic backscatter of coherent laser light as a probe beam in the FO environment. The introduction of new technologies to the harsh environmental conditions of the Antarctic are often associated with high risk. However, the potential rewards of this approach (e.g. multiyear capability, minimal submerged mechanical or electrical components that may fail, relative simplicity of deployment and measurement principle, yet yielding distributed real time and spatial observation) are attractive enough to conduct a pilot project at a field-ready location (McMurdo). Current indications are that the instability of some of the world's largest ice sheets located around the Antarctic and Greenland may be caused by the presence of warming, deep ocean waters, shoaling over continental shelves, and melting the underside of floating ice shelves. Additional knowledge of the temporal and spatial variability of the temperature fields underneath terminal ice shelves, such as those draining the West Antarctic Ice Sheet, are needed to accurately project future global climate effects on ice-shelf ocean interactions, and in order to inform societal and technological aspects of adaption to changing sea-level.
ASPIRE is an NSF-funded project that will examine the ecology of the Amundsen Sea during the Austral summer of 2010. ASPIRE includes an international team of trace metal and carbon chemists, phytoplankton physiologists, microbial and zooplankton ecologists, and physical oceanographers, that will investigate why and how the Amundsen Sea Polynya is so much more productive than other polynyas and whether interannual variability can provide insight to climate-sensitive mechanisms driving carbon fluxes. This project will compliment the existing ASPIRE effort by using 1) experimental manipulations to understand photoacclimation of the dominant phytoplankton taxa under conditions of varying light and trace metal abundance, 2) nutrient addition bioassays to determine the importance of trace metal versus nitrogen limitation of phytoplankton growth, and 3) a numerical ecosystem model to understand the importance of differences in mixing regime, flow field, and Fe sources in controlling phytoplankton bloom dynamics and community composition in this unusually productive polynya system. The research strategy will integrate satellite remote sensing, field-based experimental manipulations, and numerical modeling. Outreach and education include participation in Stanford's Summer Program for Professional Development for Science Teachers, Stanford's School of Earth Sciences high school internship program, and development of curriculum for local science training centers, including the Chabot Space and Science Center. Undergraduate participation and training will include support for both graduate students and undergraduate assistants.
The proposed work is a multi-year study of the transport of water through Drake Passage by the Antarctic Circumpolar Current (ACC). Drake Passage acts as a chokepoint that is not only well suited geographically for measuring the time-varying transport, but observations and computer models suggest that dynamical balances which control the transport are particularly effective here. An array of Current Meters and Pressure-recording Inverted Echo Sounders (CPIES) will be set out for a period of 4 years to quantify the transport and dynamics of the Antarctic Circumpolar Current. Data will be collected annually by acoustic telemetry, leaving the instruments undisturbed until recovered at the end of the project. <br/><br/>The Southern Ocean is believed to be especially sensitive to climate change, responding to winds that have increased over the past thirty years, and warming significantly more than the global ocean over the past fifty years. The proposed observations will resolve the seasonal and interannual variability of the total ACC transport, as well as its vertical and lateral structure. Although not submitted specifically to the International Polar Year (IPY) Program Solicitation, the proposed project contributes to the IPY goal of understanding environmental change in polar regions and represents a pulse of activity in the IPY time frame that will extend the legacy of the IPY. The data and findings will be reported to publicly accessible archives and submitted for publication in the scientific literature. It is a scientific collaboration between the University of California, San Diego, and the University of Rhode Island.
The mesosphere and lower thermosphere (MLT), at an altitude between 80 and 120 km above the Earth's surface, is a highly dynamic region that couples the lower terrestrial atmosphere (troposphere and stratosphere) with the upper atmosphere near-Earth space environment (thermosphere and ionosphere). Of particular importance in this region are both the upward propagating thermally forced atmospheric tides and global scale planetary waves. Both of these phenomena transport heat and momentum from the lower atmosphere into the upper atmosphere. Studies in recent years have indicated that the Arctic and Antarctic MLT possess a rich spectrum waves and may be more sensitive to global change than the lower atmosphere. The primary goal of this research is to observe, quantify, model, and further understand the spatial-temporal structure and variability of the MLT circulation above Antarctica and its commonalities with the Arctic. A secondary goal is to quantify and understand the deposition of mass into the upper atmosphere through the ablation of meteors and the resulting effect on local and regional aeronomic processes. This includes the effect of meteor flux, temperature and dynamics on the seasonal distribution of sodium over the South Pole. Meteor radar was installed at the South Pole Amundsen-Scott station and has been running continuously since January 2002. A new sodium nightglow imager will be installed at the South Pole to infer the sodium abundance in the MLT. Observations from this instrument will be combined with the South Pole Fabry-Perot interferometer temperature measurements and the meteor radar wind and meteor flux measurements to improve our understanding of the sodium chemistry and dynamics. These observations will be interpreted using sophisticated numerical models and interpreted in conjunction with Arctic measurements along with current linear and nonlinear atmospheric models to advance the current understanding of processes important to the MLT region. This research also contributes to the training and education of the graduate and undergraduate students, a postdoc and early career tenure track faculty.
Ammonia oxidation is the first step in the conversion of regenerated nitrogen to dinitrogen gas, a 3-step pathway mediated by 3 distinct guilds of bacteria and archaea. Ammonia oxidation and the overall process of nitrification-denitrification have received relatively little attention in polar oceans where the effects of climate change on biogeochemical rates are likely to be pronounced. Previous work on Ammonia Oxidizing Archaea (AOA) in the Palmer LTER study area West of the Antarctic Peninsula (WAP), has suggested strong vertical segregation of crenarchaeote metabolism, with the "winter water" (WW, ~50-100 m depth range) dominated by non-AOA crenarchaeotes, while Crenarchaeota populations in the "circumpolar deep water" (CDW), which lies immediately below the winter water (150-3500 m), are dominated by AOA. Analysis of a limited number of samples from the Arctic Ocean did not reveal a comparable vertical segregation of AOA, and suggested that AOA and Crenarchaeota abundance is much lower there than in the Antarctic. These findings led to 3 hypotheses that will be tested in this project: 1) the apparent low abundance of Crenarchaeota and AOA in Arctic Ocean samples may be due to spatial or temporal variability in populations; 2) the WW population of Crenarchaeota in the WAP is dominated by a heterotroph; 3) the WW population of Crenarchaeota in the WAP "grows in" during spring and summer after this water mass forms. <br/><br/>The study will contribute substantially to understanding an important aspect of the nitrogen cycle in the Palmer LTER (Long Term Ecological Research) study area by providing insights into the ecology and physiology of AOA. The natural segregation of crenarchaeote phenotypes in waters of the WAP, coupled with metagenomic studies in progress in the same area by others (A. Murray, H. Ducklow), offers the possibility of major breakthroughs in understanding of the metabolic capabilities of these organisms. This knowledge is needed to model how water column nitrification will respond to changes in polar ecosystems accompanying global climate change. The Principal Investigator will participate fully in the education and outreach efforts of the Palmer LTER, including making highlights of our findings available for posting to their project web site and participating in outreach (for example, Schoolyard LTER). The research also will involve undergraduates (including the field work if possible) and will support high school interns in the P.I.'s laboratory over the summer.
Intellectual Merit: The Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) is a study of ocean mixing in the Antarctic Circumpolar Current (ACC) which runs west to east all around the continent of Antarctica, south of the other continents. This current system is somewhat of a barrier to transport of heat, carbon dioxide and other important ocean constituents between the far south and the rest of the ocean, and mixing processes play an important role in those transports. DIMES is a multi-investigator cooperative project, led by physical oceanographers in the U.S. and in the U.K. A passive tracer and an array of sub-surface floats were deployed early in 2009 more than 2000 km west of Drake Passage on a surface of constant density about 1500 m deep between the Sub Antarctic Front and the Polar Front of the ACC. In early 2010 a U.S. led research cruise sampled the tracer, turbulence levels, and the velocity and density profiles that govern the generation of that turbulence, and additional U.K. led research cruises in 2011 and 2012 continue this sampling as the tracer has made its way through Drake Passage, into the Scotia Sea, and over the North Scotia Ridge, a track of more than 3000 km. The initial results show that diapycnal, i.e., vertical, mixing west of Drake Passage where the bottom is relatively smooth is no larger than in most other regions of the open ocean. In contrast, there are strong velocity shears and intense turbulence levels over the rough topography in Drake Passage and diapycnal diffusivity of the tracer more than 10 times larger in Drake Passage and to the east than west of Drake Passage. The DIMES field program continues with the U.S. team collecting new velocity and turbulence data in the Scotia Sea. It is anticipated that the tracer will continue passing through the Scotia Sea until at least early 2014. The U.K. partners have scheduled sampling of the tracer on cruises at the North Scotia Ridge and in the eastern and central Scotia Sea in early 2013 and early 2014. The current project will continue the time series of the tracer at Drake Passage on two more U.S. led cruises, in late 2012 and late 2013. Trajectories through the Scotia Sea estimated from the tracer observations, from neutrally buoyant floats, and from numerical models will be used to accurately estimate mixing rates of the tracer and to locate where the mixing is concentrated. During the 2013 cruise the velocity and turbulence fields along high-resolution transects along the ACC and across the ridges of Drake Passage will be measured to see how far downstream of the ridges the mixing is enhanced, and to test the hypothesis that mixing is enhanced by breaking lee waves generated by flow over the rough topography. Broader Impacts: DIMES (see web site at http://dimes.ucsd.edu) involves many graduate students and post-doctoral researchers. Two graduate students, who would become expert in ocean turbulence and the processes generating it, will continue be trained on this project. The work in DIMES is ultimately motivated by the need to understand the overturning circulation of the global ocean. This circulation governs the transport and storage of heat and carbon dioxide within the huge oceanic reservoir, and thus plays a major role in regulating the earth?s climate. Understanding the circulation and how it changes in reaction to external forces is necessary to the understanding of past climate change and of how climate might change in the future, and is therefore of great importance to human well-being. The data collected and analyzed by the DIMES project will be assembled and made publicly available at the end of the project. The DIMES project is a process experiment sponsored by the U.S. CLIVAR (Climate variability and predictability) program.
Hofmann, Eileen; Dinniman, Michael; Klinck, John M.
No dataset link provided
Abstract<br/><br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>The Ross Sea is a highly productive area within the Southern Ocean, but it experiences substantial variability in both physical (temperature, ice concentrations, salinity, winds, and current velocities) and biogeochemical (chlorophyll, productivity, micronutrients, higher trophic level standing stocks, gases, etc.) conditions. Understanding the temporal and spatial oceanographic variations in physical forcing is essential to understanding the ecological functioning within the Ross Sea. There are a number of models of the physical oceanography of the Ross Sea that characterize the observed circulation. Unfortunately, data on the appropriate time scales (daily, monthly, seasonal, and interannual) to completely evaluate those models are lacking. The proposed research is a demonstration project to characterize the physical and biological oceanography of the southern Ross Sea using newly developed Glider technology to sample the region continuously through the growing season, to collect temperature, salinity, fluorescence, oxygen and optical transmission data. These field data will be used to assist in evaluation of an eddy-resolving ROMS-based coupled circulation-biological model, and, along with satellite ocean color information, will be assimilated into an ecosystem model. Data assimilation techniques will reduce the model uncertainties of the circulation and food webs of the region. The intellectual merit of this effort arises from the combination of field-based investigations using a novel technology (one that is far more cost-effective than ship-based studies) with state-of-the-art biological-physical models and advanced data assimilation techniques. The research will provide new insights into the complex oceanographic phenomena of the Antarctic continental shelves and is a novel method of continuing the studies of the southern Ross Sea. Broader impacts of the proposed research include training of graduate and undergraduate students and partnership with several ongoing outreach programs dealing with scientific research in the Southern Ocean. At least 2 graduate students will be supported by this research, and it will be a critical component of a variety of outreach programs in Virginia, including a High School Marine Science Day, Boy and Girl Scout education, and middle school curriculum improvement. The investigators also will create a web site to foster immediate release of the data collected by the glider, and seek a linkage with schools at various levels (middle, high school and Universities) that potentially could incorporate the data into classroom activities
Hulbe/0838810 <br/><br/>This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>This award supports a modeling study of the processes in West Antarctic grounding zones, the transition from ice resting on bedrock to ice floating on the ocean surface with an eye toward understanding the interrelated causes of rapid change in grounding line configuration and outlet flow. A combination of satellite remote sensing and numerical modeling will be used to investigate both past and ongoing patterns of change. New high-resolution surface elevation maps made from a novel combination of satellite laser altimetry and remotely observed surface shape provide a unique view of grounding zones. These data will be used to diagnose events associated with the shutdown of Kamb Ice Stream, to investigate a recent discharge event on Institute Ice Stream and to investigate ongoing change at the outlet of Whillans Ice Stream, along with other modern processes around the West Antarctic. An existing numerical model of coupled ice sheet, ice stream, and ice shelf flow will be used and improved as part of the research project. The broader impacts of the project relate to the importance of understanding the role of polar ice sheets in global sea level rise. The work will contribute to the next round of deliberations for the Intergovernmental Panel on Climate Change (IPCC). Improved views, interpretations, and insights into the physical processes that govern variability in ice sheet outlet streams will help correct the shortcomings of the last IPCC report that didn?t include the role of ice sheets in sea level rise. The PIs have a strong record of public outreach, involvement in the professional community, and student training.
Since 1990, Palmer LTER (PAL) research has been guided by the hypothesis that variability in the polar marine ecosystem is mechanistically coupled to changes in the annual advance, retreat and spatial extent of sea ice. Since that time, the hypothesis has been modified to incorporate climate migration, i.e. the displacement of a cold, dry polar climate by a warm, moist climate regime in the northern component of the PAL region, producing fundamental changes in food web structure and elemental cycling. The observed northern changes are affecting all trophic levels and elemental cycling, and the primary mechanism of change involves match-mismatch dynamics. The proposed research builds on previous findings, with a new emphasis on process studies and modeling to elucidate the mechanistic links between teleconnections, climate change, physical oceanographic forcing and ecosystem dynamics. The proposed research will examine the hypothesis that regional warming and sea ice decline associated with historical and on-going climate migration in the northern part of the study area have altered key phenological relationships, leading to changes in species distributions, increasing trophic mismatches and changes in habitat, food availability, ecosystem dynamics and biogeochemical cycling. Through targeted process studies linked to numerical model simulations, the research also will test the hypothesis that deep cross-shelf canyons characterizing the core study region are focal areas for ecosystem processes that result in predictable, elevated food resources for top-predators. The effort includes the addition of 3 new PIs: a zooplankton ecologist with expertise in biogeochemical fluxes, a phytoplankton ecologist focusing on bio-optics and autonomous observations using gliders, and a numerical simulation modeler specializing in coupled global models of ocean circulation, plankton ecology and biogeochemical cycles. The program will add trace metal sampling and analysis, moored physical oceanographic sensors, a moored sediment trap in the south, drifting sediment traps and stable carbon (del 13C) and nitrogen (del 15N) isotope analyses. Missions lasting up to 45 days using gliders deployed before, during and after summer cruises will, along with moorings and satellite remote sensing of sea ice, ocean color, sea surface temperatures and wind fields, greatly extend the observational program in space and time. <br/><br/>Since its inception, PAL has been a leader in Information Management to enable knowledge-building within and beyond the Antarctic, oceanographic and LTER communities. PAL has designed and deployed a new information infrastructure with a relational database architecture to facilitate data distribution and sharing. The Education and Outreach program capitalizes on the public's fascination with Antarctica to promote scientific literacy from kindergarten students to adult citizens concerned with climate change and environmental sustainability. Through communicating results to the public and working with scientific assessment bodies (e.g., IPCC) and Antarctic Treaty parties to protect Earth's last frontier, PAL researchers contribute to the national scientific agenda and the greater public benefit.
Several aspect of the seasonal melting and reformation cycle of Antarctic sea ice appear to be divergent from those occurring in the Arctic. This is most clearly demonstrated by the dramatic diminishing extent and thinning of the Arctic sea ice, to be contrasted to the changes in Antarctic sea-ice extent, which recently (decadaly) shows small increases. Current climate models do not resolve this discrepancy which likely results from both a lack of relevant observational sea-ice data in the Antarctic, along with inadequacies in the physical parameterization of sea-ice properties in climate models.<br/><br/>Researchers will take advantage of the cruise track of the I/B Oden during transit through the Antarctic sea-ice zones in the region of the Bellingshausen, Amundsen and Ross (BAR) seas on a cruise to McMurdo Station. Because of its remoteness and inaccessibility, the BAR region is of considerable scientific interest as being one of the last under described and perhaps unexploited marine ecosystems left on the planet .<br/><br/>A series of on station and underway observations of sea ice properties will be undertaken, thematically linked to broader questions of summer ice survival and baseline physical properties (e.g. estimates of heat and salt fluxes). In situ spatiotemporal variability of sea-ice cover extent, thickness and snow cover depths will be observed.
This project studies the Permian-Triassic extinction event as recorded in sedimentary rocks from the Transantarctic Mountains of Antarctica. Two hundred and fifty million years ago most life on Earth was wiped out in a geologic instant. The cause is a subject of great debate. Researchers have identified a unique stratigraphic section near Shackleton glacier laid down during the extinction event. Organic matter from these deposits will be analyzed by density gradient centrifugation (DGC), which will offer detailed information on the carbon isotope composition. The age of these layers will be precisely dated by U/Pb-zircon-dating of intercalated volcanics. Combined, these results will offer detailed constraints on the timing and duration of carbon isotope excursions during the extinction, and offer insight into the coupling of marine and terrestrial carbon cycles. The broader impacts of this project include graduate and undergraduate student research, K12 outreach and teacher involvement, and societal relevance of the results, since the P/T extinction may have been caused by phenomena such as methane release, which could accompany global warming.
Rice, James; Platt, John; Suckale, Jenny; Perol, Thibaut; Tsai, Victor
No dataset link provided
Rice 0739444<br/><br/>This award supports a project to study the mode of formation and causes of glacial earthquakes. The paradigm for glacial flow has been that glaciers flow in a viscous manner, with major changes in the force balance occurring on the decade timescale or longer. The recent discovery of a number of even shorter timescale events has challenged this paradigm. In 2003, it was discovered that Whillans Ice Stream in West Antarctica displays stick-slip behavior on the 10-30 minute timescale, with ice stream speed increasing by a factor of 30 from already high speeds. In the past year, the minimum timescale has been pushed shorter by recognition that a class of recently discovered 50-second-long, magnitude-5 earthquakes are closely associated with changes in the force balance near the calving fronts of large outlet glaciers in both Greenland and East Antarctica. With no adequate theory existing to explain these relatively large earthquakes associated with outlet glaciers, we have begun to investigate the physical mechanisms that must be involved in allowing such a response in a system traditionally not thought capable of generating large variations in forces over timescales less than 100 seconds. The intellectual merit of the work is that large-amplitude, short-timescale variability of glaciers is an important mode of glacier dynamics that has not yet been understood from a first-principles physics perspective. The proposed research addresses this gap in understanding, tying together knowledge from numerous disciplines including glaciology, seismology and fault rupture dynamics, laboratory rock physics, granular flow, fracture mechanics, and hydrogeology. The broader impacts of the work are that there is societal as well as general scientific interest in the stability of the major ice sheets. However, without an understanding of the physical processes governing short time scale variability, it is unlikely that we will be able accurately predict the future of these ice sheets and their impact on sea level changes. The project will also contribute to the development and education of young scientists.
Joughin 0631973<br/><br/>This award supports a project to gather data to better understand the mass balance of the West Antarctic Ice Sheet, in the Pine Island and Thwaites region, through the combination of radar altimetry and surface-based ice-core measurements of accumulation. The intellectual merit of the project is that the results of the field work will provide information on decadal-scale average accumulation extending back through the last century and will help constrain a modeling effort to determine how coastal changes propagate inland, to allow better prediction of future change. Comparison of the basin averaged accumulation with ice discharge determined using Interferometric Synthetic Aperture Radar (InSAR) velocity data will provide improved mass-balance estimates. Study of changes in flow speed will produce a record of mass balance over the last three decades. Analysis of the satellite altimeter record in conjunction with annual accumulation estimates also will provide estimates of changes and variability in mass balance. The broader impacts of the work are that it will make a significant contribution to future IPCC estimates of sea level, which are important for projection of the impacts of increased sea level on coastal communities. The research will contribute to the graduate education of students at the Universities of Washington and Kansas and will enrich K-12 education through the direct participation of the PIs in classroom activities. Informal science education includes 4-day glacier flow demonstrations at the Polar Science Weekend held annually at the Pacific Science Center in Seattle. The project also will communicate results through Center for the Remote Sensing of Ice Sheets (CReSIS) outreach effort. All field and remotely-sensed data sets will be archived and distributed by the National Snow and Ice Data Center. This project is relevant to IPY in that the West Antarctic Ice Sheet is losing mass, in large part because of rapid thinning of the Amundsen Coast glaciers so, it will directly address the NSF IPY emphasis on "ice sheet history and dynamics." The project is also international in scope.
Brook 0739766<br/><br/>This award supports a project to create a 25,000-year high-resolution record of atmospheric CO2 from the WAIS Divide ice core. The site has high ice accumulation rate, relatively cold temperatures, and annual layering that should be preserved back to 40,000 years, all prerequisite for preserving a high quality, well-dated CO2 record. The new record will be used to examine relationships between Antarctic climate, Northern Hemisphere climate, and atmospheric CO2 on glacial-interglacial to centennial time scales, at unprecedented temporal resolution. The intellectual merit of the proposed work is simply that CO2 is the most important greenhouse gas that humans directly impact, and understanding the sources, sinks, and controls of atmospheric CO2 is a major goal for the global scientific community. Accurate chronology and detailed records are primary requirements for developing and testing models that explain and predict CO2 variability. The proposed work has several broader impacts. It contributes to the training of a post-doctoral researcher, who will transfer to a research faculty position during the award period and who will participate in graduate teaching and guest lecture in undergraduate courses. An undergraduate researcher will gain valuable lab training and conduct independent research. Bringing the results of<br/>the proposed work to the classroom will enrich courses taught by the PI. Outreach efforts will expose pre-college students to ice core research. The proposed work will enhance the laboratory facilities for ice core research at OSU, insuring that the capability for CO2 measurements exists for future projects. All data will be archived at the National Snow and Ice Data Center and other similar archives, per OPP policy. Highly significant results will be disseminated to the news media through OSU?s very effective News and Communications group. Carbon dioxide is the most important greenhouse gas that humans are directly changing. Understanding how CO2 and climate are linked on all time scales is necessary for predicting the future behavior of the carbon cycle and climate system, primarily to insure that the appropriate processes are represented in carbon cycle/climate models. Part of the proposed work emphasizes the relationship of CO2 and abrupt climate change. Understanding how future abrupt change might impact the carbon cycle is an important issue for society.
This study will investigate how the Antarctic Slope Front and continental slope morphology determine the exchanges of mass, heat, and fresh water between the shelf and the deep ocean, in particular those leading to outflows of dense water into intermediate and deep layers of the adjacent basins and into the world ocean circulation <br/>While the importance to the global ocean circulation and climate of cold water masses originating in the Antarctic is unquestioned, the processes by which these water masses enter the deep ocean circulation are not. The primary goal of this work therefore is to identify the principal physical processes that govern the transfer of shelf-modified dense water into intermediate and deep layers of the adjacent deep ocean. At the same time, it seeks to understand the compensatory poleward flow of waters from the oceanic regime. The upper continental slope has been identified as the critical gateway for the exchange of shelf and deep ocean waters. Here the topography, velocity and density fields associated with the nearly ubiquitous front must strongly influence the advective and turbulent transfer of water properties between the shelf and oceanic regimes. The study has four specific objectives: [1] Determine the mean frontal structure and the principal scales of variability, and estimate the role of the front on cross-slope exchanges and mixing of adjacent water masses; [2] Determine the influence of slope topography and bathymetry on frontal location and outflow of dense Shelf Water; [3] Establish the role of frontal instabilities, benthic boundary layer transports, tides and other oscillatory processes on cross-slope advection and fluxes; and [4] Assess the effect of diapycnal mixing, lateral mixing identified through intrusions, and nonlinearities in the equation of state on the rate of descent and the fate of outflowing, near-freezing Shelf Water.
This project studies remnant magnetization in igneous rocks from the Dufek igneous complex, Antarctica. Its primary goal is to understand variations in the Earth's magnetic field during the Mesozoic Dipole Low (MDL), a period when the Earth's magnetic field underwent dramatic weakening and rapid reversals. This work will resolve the MDL's timing and nature, and assess connections between reversal rate, geomagnetic intensity and directional variability, and large-scale geodynamic processes. The project also includes petrologic studies to determine cooling rate effects on magnetic signatures, and understand assembly of the Dufek as an igneous body. Poorly studied, the Dufek is amongst the world's largest intrusions and its formation is connected to the break-up of Gondwana. <br/><br/>The broader impacts of this project include graduate and undergraduate education and international collaboration with a German and Chilean IPY project.
Intellectual Merit: The PI proposes a high-resolution paleoenvironmental study of pollen, spore, fresh-water algae, and dinoflagellate cyst assemblages to investigate the palynological record of sudden warming events in the Antarctic as recorded by the ANDRILL SMS drill core and terrestrial sections. These data will be used to derive causal mechanisms for these rapid climate events. Terrestrial samples will be obtained at various altitudes in the Dry Valleys region. The pollen and spores will provide data on atmospheric conditions, while the algae will provide data on sea-surface conditions. These data will help identify the triggers for sudden climatic shifts. If they are caused by changes in oceanic currents, a signal will be visible in the dinocyst assemblages first as currents influence their distribution. Conversely, if these shifts are triggered by atmospheric factors, then the shifts will first affect plants and be visible in the pollen record. Broader impacts: The PI proposes a suite of activities to bring field-based climate change research to a broader audience. The PI will advise a diverse group of students and educators. The palynological data collected as part of this research will be utilized, in part, to develop new lectures on Antarctic palynology and these new lectures will be made available via a collaboration with the LSU HHMI program. In addition, the PI will direct three Louisiana middle-school teachers as they pursue a Masters of Natural Science for science educators. These teachers will help the PI develop a professional development program for science teachers. Community-based activities will be organized to raise science awareness and alert students and the public of opportunities in science.
Winckler/0636898<br/><br/>This award supports a project to study dust sources in Antarctic ice cores. Atmospheric aerosols play an important role both in global biogeochemical cycles as well as in the climate system of the Earth. Records extracted from Antarctic ice cores inform us that dust deposition from the atmosphere to the ice sheet was 15-20 times greater during glacial periods than during interglacials, which raises the possibility that dust may be a key player in climate change on glacial-interglacial timescales. By characterizing potential source areas from South America, South Africa, and Australia as well as fresh glacial flour from Patagonia, the project will determine if the interglacial dust was mobilized from a distinct geographical region (e.g., Australia) or from a more heavily weathered source region in South America. The intellectual merit of the project is that it will contribute to reconstructing climate-related changes in the rate of dust deposition, and in the provenance of the dust, it will provide critical constraints on hydrology and vegetation in the source regions, as well as on the nature of the atmospheric circulation transporting dust to the archive location. In a recent pilot study it was found that there is a dramatic glacial to Holocene change in the 4He/Ca ratio in the dust extracted from ice from Dronning Maud Land, Antarctica, indicating a shift in the source of dust transported to Antarctica. The broader impacts of the project are that Helium isotopes and calcium measurements provide a wealth of information that can then be turned into critical input for dust-climate models. Improved models, which are able to accurately reconstruct paleo dust distribution, will help us to predict changes in dust in response to future climate variability. This information will contribute to an improvement of our integrated understanding of the Earth's climate system and, in turn, will better inform policy makers of those processes and conditions most susceptible to perturbation by climate change, thereby leading to more meaningful climate-change policy. The project will support a graduate student in the dual masters Earth and Environmental Science Journalism program. The lead-PI manages the rock noble gas laboratory at Lamont. Her leadership role in this facility impacts the training of undergraduate and graduate students as well as visiting scientists.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The project will employ a sophisticated meteor radar at the Brazilian Antarctic station Comandante Ferraz on King George Island for a number of synergetic research efforts of high interest to the international aeronomical community. The location of the radar will be at the tip of the Antarctic Peninsula - at a critical southern latitude of 62 degrees - to fill a current measurement gap from 54 to 68 degrees south. The radar will play a key role in Antarctic and inter-hemispheric studies of neutral atmosphere dynamics, defining global mesosphere and lower thermosphere structure and variability (from 80 to 105 km) and guiding advances of models accounting for the dynamics of this high-altitude region, including general circulation models, and climate and numerical weather prediction models. The unique radar measurement sensitivity will enable studies of: (1) the large-scale circulation and planetary waves, (2) the tidal structure and variability, (3) the momentum transport by small-scale gravity waves, (4) important, but unquantified, gravity wave - tidal interactions, (5) polar mesosphere summer echoes, and (6) meteor fluxes, head echoes, and non-specular trails, a number of which exhibit high latitudinal gradients at these latitudes. This radar will support extensive collaborations with U.S. and other scientists making measurements at other Antarctic and Arctic conjugate sites, including Brazilian scientists at C. Ferraz and U.S. and international colleagues having other instrumentation in the Antarctic, Arctic, and within South America. Links to the University of Colorado in the U.S., Instituto Nacional de Pesquisas Espaciais (INPE) in Brazil and Universidad Nacional de La Plata in Argentina will provide unique research opportunities for graduate and undergraduate students in the U.S. and South America.
9909367 Leventer This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a multi-institutional, international (US - Australia) marine geologic and geophysical investigation of Prydz Bay and the MacRobertson Shelf, to be completed during an approximately 60-day cruise aboard the RVIB N.B. Palmer. The primary objective is to develop a record of climate and oceanographic change during the Quaternary, using sediment cores collected via kasten and jumbo piston coring. Core sites will be selected based on seismic profiling (Seabeam 2112 and Bathy2000). Recognition of the central role of the Antarctic Ice Sheet to global oceanic and atmospheric systems is based primarily on data collected along the West Antarctic margin, while similar extensive and high resolution data sets from the much more extensive East Antarctic margin are sparse. Goals of this project include (1) development of a century- to millennial-scale record of Holocene paleoenvironments, and (2) testing of hypotheses concerning the sedimentary record of previous glacial and interglacial events on the shelf, and evaluation of the timing and extent of maximum glaciation along this 500 km stretch of the East Antarctic margin. High-resolution seismic mapping and coring of sediments deposited in inner shelf depressions will be used to reconstruct Holocene paleoenvironments. In similar depositional settings in the Antarctic Peninsula and Ross Sea, sedimentary records demonstrate millennial- and century- scale variability in primary production and sea-ice extent during the Holocene, which have been linked to chronological periodicities in radiocarbon distribution, suggesting the possible role of solar variability in driving some changes in Holocene climate. Similar high-resolution Holocene records from the East Antarctic margin will be used to develop a circum-Antarctic suite of data regarding the response of southern glacial and oceanographic systems to late Quaternary climate change. In addition, these data will help us to evaluate the response of the East Antarctic margin to global warming. Initial surveys of the Prydz Channel - Amery Depression region reveal sequences deposited during previous Pleistocene interglacials. The upper Holocene and lower (undated) siliceous units can be traced over 15,000 km2 of the Prydz Channel, but more sub-bottom seismic reflection profiling in conjunction with dense coring over this region is needed to define the spatial distribution and extent of the units. Chronological work will determine the timing and duration of previous periods of glacial marine sedimentation on the East Antarctic margin during the late Pleistocene. Analyses will focus on detailed sedimentologic, geochemical, micropaleontological, and paleomagnetic techniques. This multi-parameter approach is the most effective way to extract a valuable paleoenvironmental signal in these glacial marine sediments. These results are expected to lead to a significant advance in understanding of the behavior of the Antarctic ice-sheet and ocean system in the recent geologic past. The combination of investigators, all with many years of experience working in high latitude marine settings, will provide an effective team to complete the project. University and College faculty (Principal Investigators on this project) will supervise a combination of undergraduate and post-graduate students involved in all stages of the project so that educational objectives will be met in tandem with the research goals of the project.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>The Amundsen Sea Polynya is areally the most productive Antarctic polynya, exhibits higher chlorophyll levels during peak bloom and greater interannual variability than the better-studied Ross Sea Polynya ecosystem. Polynyas may be the key to understanding the future of polar regions as their extent is expected to increase with anthropogenic warming. The project will examine 1) sources of iron to the Amundsen Sea Polynya as a function of climate forcing, 2) phytoplankton community structure in relation to iron supply and mixed-layer depths, 3) the efficiency of the biological pump of carbon to depth and 4) the net flux of carbon as a function of climate and micronutrient forcing. The research also will compare results for the Amundsen Sea to existing data synthesis and modeling efforts for the Palmer LTER and Ross Sea. The project will 1) build close scientific collaborations between US and Swedish researchers; 2) investigate climate change implications with broad societal relevance; 3) train new researchers; 4) encourage participation in research science by underrepresented groups, and 5) involve broad dissemination of results via scientific literature and public outreach, including close interactions with NSF-supported PolarTrec and COSEE K-12 teachers.
This award supports a project of scientific investigations along two overland traverses in East Antarctica: one going from the Norwegian Troll Station (72deg. S, 2deg. E) to the United States South Pole Station (90deg. S, 0deg. E) in 2007-2008; and a return traverse starting at South Pole Station and ending at Troll Station by a different route in 2008-2009. The project will investigate climate change in East Antarctica, with the goals of understanding climate variability in Dronning Maud Land of East Antarctica on time scales of years to centuries and determining the surface and net mass balance of the ice sheet in this sector to understand its impact on sea level. The project will also investigate the impact of atmospheric and oceanic variability and human activities on the chemical composition of firn and ice in the region, and will revisit areas and sites first explored by traverses in the 1960's, for detection of possible changes and to establish benchmark datasets for future research efforts. In terms of broader impacts, the results of this study will add to understanding of climate variability in East Antarctica and its contribution to global sea level change. The project includes international exchange of graduate students between the institutions involved and international education of undergraduate students through classes taught by the PI's at UNIS in Svalbard. It involves extensive outreach to the general public both in Scandinavia and North America through the press, television, science museums, children's literature, and web sites. Active knowledge sharing and collaboration between pioneers in Antarctic glaciology from Norway and the US, with the international group of scientists and students involved in this project, provide a unique opportunity to explore the changes that half a century have made in climate proxies from East Antarctica, scientific tools, and the culture and people of science. The project is relevant to the International Polar Year (IPY) since it is a genuine collaboration between nations: the scientists involved have complementary expertise, and the logistics involved relies on assets unique to each nation. It is truly an endeavor that neither nation could accomplish alone. This project is a part of the Trans- Antarctic Scientific Traverse Expeditions Ice Divide of East Antarctica (TASTE-IDEA) which is also part of IPY.
This award supports a project to examine an existing ice core of opportunity from South Pole (SPRESO core) to develop a 2000+ year long climate record. SPRESO ice core will be an annually dated, sub-annually-resolved reconstruction of past climate (atmospheric circulation, temperature, precipitation rate, and atmospheric chemistry) utilizing continuous, co-registered measurements (n=45) of: major ions, trace elements, and stable isotope series, plus selected sections for microparticle size and composition. The intellectual merit of this project relates to the fact that few 2000+ year records of this quality exist in Antarctica despite increasing scientific interest in this critical time period as the framework within which to understand modern climate. The scientific impact of this ice core investigation are that it will provide an in-depth understanding of climate variability; a baseline for assessing modern climate variability in the context of human activity; and a contribution to the prediction of future climate variability. The broader impact of this work is that the proposed research addresses important questions concerning the role of Antarctica in past, present, and future global change. Results will be translated into publicly accessible information through public lectures, media appearances, and an extensive outreach activity housed in our Institute. Our ice core activities provide a major basis for curriculum in K-12 and University plus a basis for several field and laboratory based graduate theses and undergraduate student projects. The project will support one PhD student for 3 years and undergraduate salaries. The Climate Change Institute has a long history of gender and ethnically diverse student and staff involvement in research.
95-30398 Anderson This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. The overall objectives of JGOFS are to determine and understand processes controlling the time-varying fluxes of carbon and associated biogenic elements, and to predict the response of marine biogeochemical processes to climate change. The Southern Ocean is critical in the global carbon cycle, as judged by its size and the physical processes which occur in it (e.g., deep and intermediate water formation), but its present quantitative role is uncertain. JGOFS objectives for the Southern Ocean study are as follows: 1) to constrain the fluxes of carbon (organic and inorganic) and to place these fluxes in the context of the contemporary carbon cycle; 2) to identify the factors and processes which regulate the magnitude and variability of primary productivity and the fate of biogenic matter; 3) to determine the response of the Southern Ocean to natural climate perturbations; and 4) to predict the response of the Southern Ocean to climate change. In order to successfully address these objectives, a large field program has been designed to provide various investigators the opportunity to test specific hypotheses which relate to these broadly-defined objectives. We expect the field test to begin in September 1996, and last through March 1998 using two ships, the R.V. Palmer, and the R.V. Thompson. As most of the investigators will use hydrographic and nutrient data from these cruises, this proposal requests funds for the support of the analysis of nutrient concentrations during these thirteen crui ses. A team of oceanographic experts from a variety of institutions has been assembled to complete these analyses; furthermore, the data will be scrutinized for errors and provided in a timely fashion to all PI's in the project, as well as to the relevant oceanographic data storage facilities. The hydrography and coring groups have been put together using the successful model for the Arabian Sea JGOFS study, and in conjunction with the nutrient data (supported under a separate proposal), will form a large portion of the Southern Ocean JGOFS database which both field investigators and modelers will use to clarify the role of the Southern Ocean in the global carbon cycle.
The annual advance and retreat of pack ice may be the major physical determinant of spatial and temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a six to eight year cycle in the maximum extent of pack ice in the winter. During this decade, winters were colder in 1980 and 1981, and again in 1986 and 1987. Winter-over survival in Adelie penguins varied on the same cycle, higher in winters with heavy pack ice. This Long Term Ecological Research (LTER) project will define ecological processes linking the extent of annual pack ice with the biological dynamics of different trophic levels within antarctic marine communities. The general focus is on interannual variability in representative populations from the antarctic marine food web and on mechanistic linkages that control the observed variability in order to develop broader generalizations applicable to other large marine environments. To achieve these objectives, data from several spatial and temporal scales, including remote sensing, a field approach that includes an annual monitoring program, a series of process-oriented research cruises, and a modeling effort to provide linkages on multiple spatial and temporal scales between biological and environmental components of the ecosystem will be employed.
9528807 Gordon The proposed project is part of a multi-institutional integrated study of the outflow of newly formed bottom water from the Weddell Sea and its dispersion into the South Atlantic Ocean. It builds upon earlier successful studies of the inflow of intermediate water masses into the Eastern Weddell Sea, their modification within the Weddell Gyre, and their interaction with bottom water formation processes in the western Weddell Sea. The study is called Deep Ocean Ventilation Through Antarctic Intermediate Layers (DOVETAIL) and includes six components involving hydrographic measurements, natural tracer experiments, and modeling studies. The study will be centered east of the Drake Passage where water masses from the Weddell Sea and the Scotia Sea come together in the Weddell-Scotia Confluence, and will be carried out in cooperation with the national antarctic programs of Germany and Spain. This particular component concerns observations of the temperature and salinity structure, as well as the chemical nature of the water column in the confluence region. The study has four related objectives. The first is to assess the quantity and the physical and chemical characteristics of Weddell Sea source waters for the confluence. The second is to describe the dominant processes associated with spreading and sinking of dense antarctic waters within the Weddell-Scotia Confluence. The third is to estimate the ventilation rate of the world ocean, and the fourth is to estimate seasonal fluctuations in the regional ocean transport and hydrographic structure and to assess the likely influence of seasonal to interannual variability on rates of ventilation by Weddell Sea waters. Ventilation of the deep ocean -- the rising of sub-surface water masses to the surface to be recharged with atmospheric gases and to give up heat to the atmosphere -- is a uniquely antarctic phenomenon that has significant consequences for global change by affecting the g lobal reservoir of carbon dioxide, and by modulating the amount and extent of seasonal sea ice in the southern hemisphere. This component will make systematic observations of the temperature salinity structure of the water and undertake an extensive sampling program for other chemical studies. The purpose is to identify the individual water masses and to relate their temperature and salinity characteristics to the modification processes within the Weddell Sea. ***
9816616 Trivelpiece Long-term seabird research conducted at Admiralty Bay, which is located on King George Island in the Antarctic Peninsula region, has documented annual variability in the life history parameters of the breeding biology and ecology of the Adelie, gentoo and chinstrap penguins. Twenty-year records acquired on these species, including survival and recruitment, population size and breeding success, and diets and foraging ecology have enabled scientists to test key hypotheses regarding the linkage between these predator parameters and variability in the Antarctic marine ecosystem. This project will focus on understanding the linkages between the physical environment and the population biology of penguins, in particular, sea ice coverage and its impact on krill availability as a food source for penguins. Krill is a key food web species in the Antarctic oceans and accounts for nearly one hundred percent of the prey eaten by dominant predators such as baleen whales, seals and penguins. Analysis of long-term data sets has suggested that years of heavy winter sea ice favor krill recruitment, as larval krill find refuge and food in the sea ice habitat. It has also been observed that years of heavy sea ice favor Adelie penguin recruitment and not that of chinstrap penguins. Aspects of the work include analysis of diet samples, shipboard krill sampling, survival and recruitment studies of penguins, satellite tracking of penguins during the breeding season, and analysis of satellite sea ice images. Penguins are the key species used to monitor the impact of commercial fisheries activities in the region, so this study will provide useful information to the Convention for the Conservation of Antarctic Marine Living Resources, which is the part of the Antarctic Treaty System which focuses on fisheries management.
This project is a contribution to a coordinated attempt to understand the interactions of biological and physical dynamics by developing relationships among the evolution of the antarctic winter ice and snow cover, biological habitat variability, and the seasonal progression of marine ecological processes. The work will be carried out in the context of the Southern Ocean Experiment of the Global Ocean Ecosystem Dynamics Study (Globec), a large, multi-investigator study of the winter survival strategy of krill under the antarctic sea ice in the vicinity of Marguerite Bay on the western side of the Antarctic Peninsula. The objective of this project is to make a quantitative assessment of the small scale temperature and salinity structure of the oceanic surface layer in order to study the effect of stratification and turbulence on the biochemical and biological processes under the winter sea ice. The water masses on the continental shelf off Marguerite Bay consist of inflowing Upper Circumpolar Deep Water, which is relatively warm, salty, oxygen-poor, and nutrient-rich. In winter atmospheric processes cool and freshen this water, and recharge it with oxygen to produce Antarctic Surface Water which is diffused seaward, and supports both a sea ice cover and a productive krill-based food web. The modification processes work through mixing associated with shear instabilities of the internal wave field, double diffusion of salt and heat, and mixing driven by surface stress and convection. These processes will be quantified with two microstructure profilers, capable of resolving the small but crucial vertical variations that drive these processes. ***
The Shackleton Fracture Zone (SFZ) in Drake Passage of the Southern Ocean defines a boundary between low and high phytoplankton waters. Low chlorophyll water flowing through the southern Drake Passage emerges as high chlorophyll water to the east, and recent evidence indicates that the Southern Antarctic Circumpolar Current Front (SACCF) is steered south of the SFZ onto the Antarctic Peninsula shelf where mixing between the water types occurs. The mixed water is then advected off-shelf with elevated iron and phytoplankton biomass. The SFZ is therefore an ideal natural laboratory to improve the understanding of plankton community responses to natural iron fertilization, and how these processes influence export of organic carbon to the ocean interior. The bathymetry of the region is hypothesized to influence mesoscale circulation and transport of iron, leading to the observed patterns in phytoplankton biomass. The position of the Antarctic Circumpolar Current (ACC) is further hypothesized to influence the magnitude of the flow of ACC water onto the peninsula shelf, mediating the amount of iron transported into the Scotia Sea. To address these hypotheses, a research cruise will be conducted near the SFZ and to the east in the southern Scotia Sea. A mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments will complement rapid surface surveys of chemical, plankton, and hydrographic properties. Distributions of manganese, aluminum and radium isotopes will be determined to trace iron sources and estimate mixing rates. Phytoplankton and bacterial physiological states (including responses to iron enrichment) and the structure of the plankton communities will be studied. The primary goal is to better understand how plankton productivity, community structure and export production in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and distributions of limiting nutrients. The proposed work represents an interdisciplinary approach to address the fundamental physical, chemical and biological processes that contribute to the abrupt transition in chl-a which occurs near the SFZ. Given recent indications that the Southern Ocean is warming, it is important to advance the understanding of conditions that regulate the present ecosystem structure in order to predict the effects of climate variability. This project will promote training and learning across a broad spectrum of groups. Funds are included to support postdocs, graduate students, and undergraduates. In addition, this project will contribute to the development of content for the Polar Science Station website, which has been a resource since 2001 for instructors and students in adult education, home schooling, tribal schools, corrections education, family literacy programs, and the general public.
Domack: OPP 9615053 Manley: OPP 9615670 Banerjee: OPP 9615695 Dunbar: OPP 9615668 Ishman: OPP 9615669 Leventer: OPP 9714371 Abstract This award supports a multi-disciplinary, multi-institutional effort to elucidate the detailed climate history of the Antarctic Peninsula during the Holocene epoch (the last 10,000 years). The Holocene is an important, but often overlooked, portion of the Antarctic paleoclimatic record because natural variability in Holocene climate on time scales of decades to millennia can be evaluated as a model for our present "interglacial" world. This project builds on over ten years of prior investigation into the depositional processes, productivity patterns and climate regime of the Antarctic Peninsula. This previous work identified key locations that contain ultra-high resolution records of past climatic variation. These data indicate that solar cycles operating on multi-century and millennial time scales are important regulators of meltwater production and paleoproductivity. These marine records can be correlated with ice core records in Greenland and Antarctica. This project will focus on sediment dispersal patterns across the Palmer Deep region. The objective is to understand the present links between the modern climatic and oceanographic systems and sediment distribution. In particular, additional information is needed regarding the influence of sea ice on the distribution of both biogenic and terrigenous sediment distribution. Sediment samples will be collected with a variety of grab sampling and coring devices. Analytical work will include carbon-14 dating of surface sediments using accellerator mass spectrometry and standard sedimentologic, micropaleontologic and magnetic granulometric analyses. This multiparameter approach is the most effective way to extract the paleoclimatic signals contained in the marine sediment cores. Two additional objectives are the deployment of sediment traps in front of the Muller Ice Shelf in Lallemand Fjord and seismic reflection work in conjunction with site augmentation funded through the Joint Oceanographic Institute. The goal of sediment trap work is to address whether sand transport and deposition adjacent to the ice shelf calving line results from meltwater or aeolian processes. In addition, the relationship between sea ice conditions and primary productivity will be investigated. The collection of a short series of seismic lines across the Palmer Deep basins will fully resolve the question of depth to acoustic basement. The combination of investigators on this project, all with many years of experience working in high latitude settings, provides an effective team to complete the project in a timely fashion. A combination of undergraduate, graduate and post-graduate students will be involved in all stages of the project so that educational objectives will be met in-tandem with research goals of the project.
During the past few decades of oceanographic research, it has been recognized that significant variations in biogeochemical processes occur among years. Interannual variations in the Southern Ocean are known to occur in ice extent and concentration, in the composition of herbivore communities, and in bird and marine mammal distributions and reproductive success. However, little is known about the interannual variations in production of phytoplankton or the role that these variations play in the food web. This project will collect time series data on the seasonal production of phytoplankton in the southern Ross Sea, Antarctica. Furthermore, it will assess the interannual variations of the production of the two major functional groups of the system, diatoms and Phaeocystis Antarctica, a colonial haptophyte. The Ross Sea provides a unique setting for this type of investigation for a number of reasons. For example, a de facto time-series has already been initiated in the Ross Sea through the concentration of a number of programs in the past ten years. It also is well known that the species diversity is reduced relative to other systems and its seasonal production is as great as anywhere in the Antarctic. Most importantly, seasonal production of both the total phytoplankton community (as well as its two functional groups) can be estimated from late summer nutrient profiles. The project will involve short cruises on the US Coast Guard ice breakers in the southern Ross Sea that will allow the collection of water column nutrient and particulate after data at specific locations in the late summer of each of five years. Additionally, two moorings with in situ nitrate analyzers moored at fifteen will be deployed, thus collecting for the first time in the in the Antarctic a time-series of euphotic zone nutrient concentrations over the entire growing season. All nutrient data will be used to calculate seasonal production for each year in the southern Ross Sea and compared to previously collected information, thereby providing an assessment of interannual variations in net community production. Particulate matter data will allow us to estimate the amount of export from the surface layer by late summer, and therefore calculate the interannual variability of this ecosystem process. Interannual variations of seasonal production (and of the major taxa of producers) are a potentially significant feature in the growth and survival of higher trophic levels within the food web of the Ross Sea. They are also important in order to understand the natural variability in biogeochemical processes of the region. Because polar regions such as the Ross Sea are predicted to be impacted by future climate change, biological changes are also anticipated. Placing these changes in the context of natural variability is an essential element of understanding and predicting such alterations. This research thus seeks to quantify the natural variability of an Antarctic coastal system, and ultimately understand its causes and impacts on food webs and biogeochemical cycles of the Ross Sea.
The annual advance and retreat of pack ice may be the major physical determinant of spatial/temporal changes in the structure and function of antarctic marine communities. Interannual cycles and/or trends in the annual extent of pack ice may also have significant effects on all levels of the food web, from total annual primary production to breeding success in seabirds. Historical records indicate a 6 to 8 year cycle in the maximum extent of pack ice in the winter. During this decade winters were colder in 1980 and 1981, and again in 1986 and 1987. In order to understand the interactions between pack ice and ecosystem dynamics, especially the influences of the well- documented interannual variability in ice cover on representative populations, a long-term ecological research (LTER) site has been established in the Antarctic Peninsula region near Palmer Station. The LTER project, will conduct comprehensive measurements of ice-dominated ecosystems in this region with a focus on primary production, krill populations and swarms and seabirds. A primary emphasis will be placed on the development of ecosystem models that will provide a predictive capability for issues related to global environmental change. This proposal will add to the existing LTER project detailed studies of the biogeochemical cycling of carbon and associated bioelements. The microbiology and carbon flux component of LTER will provide measurements of a suite of core parameters relevant to the carbon cycle and will test several hypotheses pertaining to carbon flux, including bacterial productivity and nutrient regeneration.
This project is an examination of the physical and structural properties of the antarctic ice pack in the Amundsen, Bellingshausen, and Ross Seas, with the goal of defining the geographical variability of various ice types, the deformation processes that are active in the antarctic ice pack, and the large-scale thermodynamics and heat exchange processes of the ice- covered Southern Ocean. An additional goal is to relate specific characteristics of antarctic sea ice to its synthetic aperture radar (SAR) signature as observed from satellites. Physical properties include the salinity, temperature, and brine volumes, while structural properties include the fraction of frazil, platelet, and congelation ice of the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice (which has been observed to be generally in excess of 50% in Weddell Sea ice floes) is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The integration of sea ice field observations and synthetic aperture radar data analysis and modeling studies will contribute to a better understanding of sea ice parameters and their geophysical controls, and will be useful in defining the kind of air-ice-ocean interactions that can be studied using SAR data, as well as having broader relevance and application to atmospheric, biological, and oceanographic investigations of the Southern Ocean.
Seabird research conducted at Admiralty Bay, King George Island in the Antarctic Peninsula region has documented annual variability in the life history parameters of the population biology of three related penguin species: the Adelie, the gentoo and the chinstrap (Pygoscelis adeliae, P. papua and P. antarctica, respectively). This long-term study has collected twenty-five years of data on the three related species, including survival and recruitment, population size and breeding success, and diets and foraging ecology. The current project will extend the research linking penguin demography and foraging ecology to variability in the Antarctic marine ecosystem. A major focus of this work will be on the Adelie and gentoo penguin population biology data and the distribution and trophic interactions among the three Pygoscelis species during the breeding season and the non-breeding, winter period. Recent results have provided the first detailed data on the wintering distributions of Adelie and chinstrap penguins in the Antarctic Peninsula region, through the use of satellite tags and time-depth recorders to examine the post-fledging foraging. Specific topics of research include an examination of the size and sex composition of krill captured by penguins feeding chicks and krill collected concurrently by net hauls in the adjacent marine environment and the length-frequency distribution of krill collected from penguin diet samples. The over winter survival of penguin breeding adults and the recruitment of young (two to four year old) pre-breeding penguins to their natal colony will be compared to the extent of sea ice in the winter prior to the breeding season. These variables are expected to be positively correlated for the Adelie but negatively correlated to the chinstrap penguin. Detailed studies of the adult gentoo penguins, which do not disperse widely from the natal colony, will be conducted using satellite tags. The data collected in this study will improve an understanding of the structure and function of the Antarctic through research on the impact of environmental variation on the structure of upper trophic level predators such as the Pygoscelis penguins.
This project is a contribution to a coordinated attempt to understand the interactions of biological and physical dynamics by developing relationships among the evolution of the antarctic winter ice and snow cover, biological habitat variability, and the seasonal progression of marine ecological processes. The work will be carried out in the context of the Southern Ocean Experiment of the Global Ocean Ecosystem Dynamics Study (Globec), a large, multi-investigator study of the winter survival strategy of krill under the antarctic sea ice in the vicinity of Marguerite Bay on the western side of the Antarctic Peninsula. There are several aspects to this project: One is the collection, analysis, and archiving of Acoustic Doppler Current Profiler (ADCP), and Conductivity-Temperature-Depth (CTD) data in order to characterize mesoscale circulation features and the regional hydrography. Another is to develop an accurate and fully validated model of tidal currents in Marguerite Bay. A third is to provide a data set of small-scale processes such as shear instabilities, tidal stirring, mesoscale eddies, and double diffusion, that are required for the effective parameterization of the vertical diffusivities of heat, salt, and nutrients. The results of this project will provide a unified data set that satisfies the data requirement of the coordinated chemical and biological studies which will link water column and sea ice processes with the biology of krill and its predators. The results further will help to link these winter observations to similar observations made in summer and elsewhere around Antarctic in the international context of the Globec program. The overall objective is to develop a comprehensive ecosystem model that will test our understanding of the system, determine its sensitivities, and to provide an organizing mechanism for integrating the Southern Ocean Globec observations. ***
Seabird research conducted at Admiralty Bay, King George Island in the Antarctic Peninsula region has documented annual variability in the life history parameters of the population biology of three related penguin species: the Adelie, the gentoo and the chinstrap (Pygoscelis adeliae, P. papua and P. antarctica, respectively). This long-term study has collected twenty-five years of data on the three related species, including survival and recruitment, population size and breeding success, and diets and foraging ecology. The current project will extend the research linking penguin demography and foraging ecology to variability in the Antarctic marine ecosystem. A major focus of this work will be on the Adelie and gentoo penguin population biology data and the distribution and trophic interactions among the three Pygoscelis species during the breeding season and the non-breeding, winter period. Recent results have provided the first detailed data on the wintering distributions of Adelie and chinstrap penguins in the Antarctic Peninsula region, through the use of satellite tags and time-depth recorders to examine the post-fledging foraging. Specific topics of research include an examination of the size and sex composition of krill captured by penguins feeding chicks and krill collected concurrently by net hauls in the adjacent marine environment and the length-frequency distribution of krill collected from penguin diet samples. The over winter survival of penguin breeding adults and the recruitment of young (two to four year old) pre-breeding penguins to their natal colony will be compared to the extent of sea ice in the winter prior to the breeding season. These variables are expected to be positively correlated for the Adelie but negatively correlated to the chinstrap penguin. Detailed studies of the adult gentoo penguins, which do not disperse widely from the natal colony, will be conducted using satellite tags. The data collected in this study will improve an understanding of the structure and function of the Antarctic through research on the impact of environmental variation on the structure of upper trophic level predators such as the Pygoscelis penguins.
An array of moorings will be deployed and maintained east of Cape Adare, Antarctica, at the northwestern corner of the Ross Sea to observe the properties of Antarctic Bottom Water (AABW) exiting the Ross Sea. This location has been identified from recent studies as an ideal place to make such measurements. Antarctic Bottom Water has the highest density of the major global water masses, and fills the deepest parts of the world's oceans. Because it obtains many of its characteristics during its contact with the atmosphere and with glacial ice along the continental margins of Antarctica, it is expected that changes in newly-formed AABW may represent an effective indicator for abrupt climate change. The heterogeneous nature of the source regions around Antarctica complicates the observation of newly-formed AABW properties. The two most important source regions for AABW are within the Weddell and the Ross Seas, with additional sources drawn from the east Antarctic margins. In the northwestern Weddell Sea, several programs have been undertaken in the last decade to monitor the long term variability of Weddell Sea Deep and Bottom Water, precursors of AABW originating from the Weddell Sea, however no such systematic efforts have yet been undertaken to make longterm measurements of outflow from the Ross Sea. The proposed study will significantly improve our knowledge of the long term variability in the outflow of deep and bottom water from the Ross Sea, and will provide the beginnings of a long-term monitoring effort which ultimately will allow detection of changes in the ocean in the context of global climate change. When joined with similar efforts ongoing in the Weddell Sea, long-term behavior and possible coupling of these two important sources of the ocean's deepest water mass can be examined in detail.
9315029 Smith The annual expansion and retreat of pack ice in the Southern Ocean are the largest seasonal processes in the World Ocean. This seasonal migration of the ice cover has a profound impact on the pelagic community in the upper 100 m of the oceanic water column where the interactions between ice cover and apex predators, such as seabirds and mammals, are most intense. This unique pelagic community has been mainly studied with ship-based operations. However, there are well recognized problems associated with shipboard sampling of the epipelagic community under pack ice and the need to monitor this community on long-time scales sufficient to examine the extreme temporal variability of this environment. To examine continuous temporal variability, the project will develop a vertically-profiling pump sampler for the collections of zooplankton and micronekton over programmable depth intervals under pack ice in the Weddell Sea. Once developed and field tested, this instrument will be deployed concurrently with previously developed upward-looking, vertically-profiling acoustic arrays for a period of one year. The combined mooring project will monitor the vertical distribution, abundance and size frequency of acoustically detectable zooplankton and micronekton in the upper 100 m of the water column in an area that experiences ice cover during 7-8 months of the year. This project will also include seasonal shipboard sampling on three cruises over the course of the one year field study. A successful deployment of these long-term mooring arrays and retrieval of data from the field will contribute to a greater understanding of how epipelagic communities function under pack ice in the Southern Ocean. This is a jointly sponsored project of the Office of Polar Programs and the Division of Ocean Sciences. ***
As long-lived animals, marine mammals must be capable of accommodating broad variations in food resources over large spatial and temporal scales. While this is true of all marine mammals, variation in the physical and biological environmental is particularly profound in the Southern Ocean. A basic understanding of the foraging behavior and habitat utilization of pelagic predators requires knowledge of this spatial and temporal variation, coupled with information of how they respond to these changes. Current understanding of these associations is primarily limited to population level studies where animal abundance has been correlated with oceanography. Although these studies are informative, they cannot provide insights into the strategies employed by individual animals nor can they provide insights into the spatial or temporal course of these interactions. <br/><br/>Recent technological advances in instrumentation make it possible to extend an understanding beyond the simple linkage of prey and predator distributions with environmental features. The key to understanding the processes that lead to high predator abundance is the identification of the specific foraging behaviors associated with different features of the water column. This study will accomplish these objectives by combining accurate positional data, measures of diving and foraging behavior, animal-derived water-column temperature and salinity data, and available oceanographic data. This project will examine the foraging behavior and habitat utilization of two species of contrasting foraging ecology, the southern elephant seal, Mirounga leonina, and the crabeater seal, Lobodon carcinophagus in the Western Antarctic Peninsula, a region of strong environmental gradients. Although these two species are phylogenetically related, they utilize substantially different but adjacent habitat types. Southern elephant seals are predominantly pelagic, moving throughout the southern ocean, venturing occasionally into the seasonal pack ice whereas crabeater seals range throughout the seasonal pack ice, venturing occasionally into open water. The relationship of specific foraging behaviors and animal movement patterns to oceanographic and bathymetric features develop and test models of the importance of these features in defining habitat use will be determined along with a comparison of how individuals of each species respond to annual variability in the marine environment. The physical oceanography of the Southern Ocean is inherently complex as are the biological processes that are intrinsically linked to oceanographic processes. Significant resources are currently being directed toward developing mathematical models of physical oceanographic processes with the goals of better understanding the role that the Southern Ocean plays in global climate processes, predicting the responses of ocean and global scale processes to climate change, and understanding the linkages between physical and biological oceanographic processes. These efforts have been limited by the scarcity of oceanographic data in the region, especially at high latitudes in the winter months. This study will provide new and significant oceanographic data on temperature and salinity profiles in to further the understanding of the dynamics of the upper water column of west Antarctic Peninsula continental shelf waters. Outreach activities include website development and an association with a marine education program at the Monterrey Bay Aquarium Research Institute.
This project examines the role of glacier dynamics in glacial sediment yields. The results will shed light on how glacial erosion influences both orogenic processes and produces sediments that accumulate in basins, rich archives of climate variability. Our hypothesis is that erosion rates are a function of sliding speed, and should diminish sharply as the glacier's basal temperatures drop below the melting point. To test this hypothesis, we will determine sediment accumulation rates from seismic studies of fjord sediments for six tidewater glaciers that range from fast-moving temperate glaciers in Patagonia to slow-moving polar glaciers on the Antarctic Peninsula. Two key themes are addressed for each glacier system: 1) sediment yields and erosion rates by determining accumulation rates within the fjords using seismic profiles and core data, and 2) dynamic properties and basin characteristics of each glacier in order to seek an empirical relationship between glacial erosion rates and ice dynamics. The work is based in Patagonia and the Antarctic Peninsula, ideal natural laboratories for these purposes because the large latitudinal range provides a large range of precipitation and thermal regimes over relatively homogeneous lithologies and tectonic settings. Prior studies of these regions noted significant decreases in glaciomarine sediment accumulations in the fjords to the south. As well, the fjords constitute accessible and nearly perfect natural sediment traps.<br/><br/>The broader impacts of this study include inter-disciplinary collaboration with Chilean glaciologists and marine geologists, support for one postdoctoral and three doctoral students, inclusion of undergraduates in research, and outreach to under-represented groups in Earth sciences and K-12 educators. The results of the project will also contribute to a better understanding of the linkages between climate and evolution of all high mountain ranges.
96-14028 Dymond This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three-year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component, a collaborative study by scientists from the Woods Hole Oceanographic Institution, Oregon State University, and the New Zealand Oceanographic Institution, concerns the export of particulate forms of carbon downward from the upper ocean. The observations will be obtained from an array of time- series sediment traps, and will be analyzed to quantify export fluxes from the Subtropical Front to the Ross Sea, over an 18- months period beginning the early austral summer of 1996. The measurement program will two annual phytoplankton blooms. The southern ocean provides a unique opportunity to investigate the processes controlling export flux in contrasting biogeochemical ocean zones demarcated by oceanic fronts. The temperature changes at the fronts coincide with gradients in nutrient concentrations and plankton ecology, resulting in a large latitudinal change in the ratio of calcium to silica taken up by the phytoplankton communities. This experiment will provide data on how the biological pump operates in the Southern Ocean and how it could potentially impact the level of atmospheric c arbon dioxide. The observed export fluxes of organic carbon, nitrogen, inorganic carbon, biogenic silica and alumina are central to the goals of the JGOFS program.
The potential consequence of human impact on wildlife in Antarctica has been debated for many decades. Scientists, support staff and visitors in Antarctica may have an effect on the behavior and population dynamics of marine mammals and seabirds. Since the early 1970's, shipboard tourism has expanded to the point where it is timely to address the question, using a scientific research approach. The focus of this study is to examine the potential effect of tourist activities on the Adelie Penguins (Pygoscelis adeliae) in the Antarctic Peninsula. The topic has gathered the interest and opinions of those in private industry, the scientific community, government organizations and environmental groups. A key concern is that increases in these activities may eventually overcome the ability of research to address critical issues in a timely and biologically meaningful manner. The approach to understanding how tourism might affect Adelie Penguins must involve both a study of human activity and a study of natural variability in the physical environment. The ongoing Palmer Long Term Ecological Research program focuses on the ecosystem and its components and thus addresses the issues of natural variability. This project focuses on the human dimension and continues a tourist-monitoring program begun as a pilot project near Palmer Station. This site is in a geographic location that mirrors current patterns in tourism and tourist-wildlife interactions in the western Antarctic Peninsula. It also offers a setting that provides unique opportunities for human impacts research. This includes the presence of long-term databases that document environmental variability over multiple time and space scales in both marine and terrestrial habitats, and the ability to examine potential tourist impacts as part of controlled experiments. The results of the study will have important implications to understanding interactions between climate change and ecosystem response, and for detecting, mitigating and managing the consequences of human activities such as tourism.
9815961 BENGTSON The pack ice region surrounding Antarctica contains at least fifty percent of the world's population of seals, comprising about eighty percent of the world's total pinniped biomass. As a group, these seals are among the dominant top predators in Southern Ocean ecosystems, and the fluctuation in their abundance, growth patterns, life histories, and behavior provide a potential source of information about environmental variability integrated over a wide range of spatial and temporal scales. This proposal was developed as part of the international Antarctic Pack Ice Seals (APIS) program, which is aimed to better understand the ecological relationships between the distribution of pack ice seals and their environment. During January-February, 2000, a research cruise through the pack ice zone of the eastern Ross Sea and western Amundsen Sea will be conducted to survey and sample along six transects perpendicular to the continental shelf. Each of these transects will pass through five environmental sampling strata: continental shelf zone, Antarctic slope front, pelagic zone, the ice edge front, and the open water outside the pack ice zone. All zones but open water will be ice-covered to some degree. Surveys along each transect will gather data on bathymetry, hydrography, sea ice dynamics and characteristics, phytoplankton and ice algae stocks, prey species (e.g., fish, cephalopods and euphausiids), and seal distribution, abundance and diet. This physical and trophic approach to investigating ecological interactions among pack ice seals, prey and the physical environment will allow the interdisciplinary research team to test the hypothesis that there are measurable physical and biological features in the Southern Ocean that result in area of high biological activity by upper trophic level predators. Better insight into the interplay among pack ice seals and biological and physical features of Antarctic marine ecosystems will allow for a better prediction of fluctuation in seal population in the context of environmental change.
This project is a contribution to a coordinated attempt to understand the interactions of biological and physical dynamics by developing mechanistic links between the evolution of the antarctic winter ice and snow cover, and biological habitat variability, through modeling the optical properties of the environment. The work will be carried out in the context of the Southern Ocean Experiment of the Global Ocean Ecosystem Dynamics Study (Globec), a large, multi-investigator study of the winter survival strategy of krill under the antarctic sea ice. The optical properties of snow and sea ice evolve through the winter and vary greatly both spectrally and spatially. These properties are an important element of the physical environment that strongly influences both the distribution of and the resources available to antarctic krill. The intensity of incident radiant energy and its distribution within the snow, ice, and water column environment, and the linked physical, optical, chemical, and biological processes that modulate its distribution are generally known but poorly quantified. The optical properties of snow and ice also influence snow algae, ice algae, and water column productivity, as well as visibility for both predator and prey. Furthermore, optical properties play an essential role in satellite observations as proxy indicators of geophysical sea ice parameters which permit local observations to be more accurately extrapolated in space and time, thus providing regional coverage that would otherwise not be possible. What is proposed is the deployment of an array of instrumented ice beacons, augmented by periodic ship-based and satellite observations, along with theoretical studies to create improved quantitative models with which to follow the temporal and spatial evolution of this snow and ice marine ecosystem. The specific objective is to develop a thermodynamic sea ice/ecosystem model through coupling of existing components in order to test our understanding of the system, determine its sensitivities, and to provide an organizing mechanism for integrating the Southern Ocean Globec observations. ***
Neale 9615342 Increases in ultraviolet-B radiation (UV-B, 280-320) associated with the Antarctic ozone hole have been shown to inhibit the photosynthesis of phytoplankton, but the overall effect on water column production is still a matter of debate and continued investigation. Investigations have also revealed that even at "normal" levels of Antarctic stratospheric ozone, UV-B and UV-A (320-400 nm) appear to have strong effects on water column production. The role of UV in the ecology of phytoplankton primary production has probably been underappreciated in the past and could be particularly important to the estimation of primary production in the presence of vertical mixing. This research focuses on quantifying UV effects on photosynthesis of Antarctic phytoplankton by defining biological weighting functions for UV-inhibition. In the past, techniques were developed to describe photosynthesis as a function of UV and visible irradiance using laboratory cultures. Further experimentation with natural assemblages from McMurdo Station in Antarctica showed that biological weighting functions are strongly related to light history. Most recently, measurements in the open waters of the Southern Ocean confirmed that there is substantial variability in the susceptibility of phytoplankton assemblages to UV. It was also discovered that inhibition of photosynthesis in Antarctic phytoplankton got progressively worse on the time scale of hours, with no evidence of recovery. Even under benign conditions, losses of photosynthetic capability persisted unchanged for several hours. This was in contrast with laboratory cultures and some natural assemblages which quickly attained a steady- state rate of photosynthesis during exposure to UV, reflecting a balance between damage and recovery processes. Slow reversal of UV-induced damage has profound consequences for water-column photosynthesis, especially during vertical mixing. Results to date have been used to model th e influence of UV, ozone depletion and vertical mixing on photosynthesis in Antarctic waters. Data indicate that normal levels of UV can have a significant impact on natural phytoplankton and that the effects can be exacerbated by ozone depletion as well as vertical mixing. Critical questions remain poorly resolved, however, and these are the focus of the present proposal. New theoretical and experimental approaches will be used to investigate UV responses in both the open waters of the Weddell-Scotia confluence and coastal waters near Palmer Station. In particular, measurements will be made of the kinetics of UV inhibition and recovery on time scales ranging from minutes to days. Variability in biological weighting functions between will be calculated for pelagic and coastal phytoplankton in the Southern Ocean. The results will provide absolute estimates of photosynthesis under in situ, as well as under altered, UV irradiance; broaden the range of assemblages for which biological weighting functions have been determined; and clarify how kinetics of inhibition and recovery should be represented in mixed layer models.
This proposal is for the continuation and expansion of an underway program on the R/V Laurence M. Gould to measure dissolved carbon dioxide gas (pCO2) along with occasional total carbon dioxide (TCO2) in surface waters on transects of Drake Passage. The added observations include dissolved oxygen, as well as nutrient and carbon-13. The proposed work is similar to the underway measurement program made aboard R/V Nathaniel B. Palmer, and complements similar surface temperature and current data.<br/>The Southern Ocean is an important component of the global carbon budget. Low surface temperatures with consequently low vertical stability, ice formation, and high winds produce a very active environment for the exchange of gaseous carbon dioxide between the atmospheric and oceanic reservoirs. The Drake Passage is the narrowest point through which the Antarctic Circumpolar Current and its associated fronts must pass, and is the most efficient location for the measurement of latitudinal gradients of gas exchange. The generated time series will contribute towards two scientific goals: the quantification of the spatial and temporal variability and trends of surface carbon dioxide, oxygen, nutrients and C-13, and an understanding of the dominant processes that contribute to the observed variability.
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to study the region recently occupied by the Larsen Ice Shelf in the Antarctic Peninsula. Over the last 10 years, scientists have observed a dramatic decay and disintegration of floating ice shelves along the northern end of the Antarctic Peninsula. Meteorological records and satellite observations indicate that this catastrophic decay is related to regional warming of nearly 3 degrees C in the last 50 years. While such retreat of floating ice shelves is unprecedented in historic records, current understanding of the natural variability of ice shelf systems over the last few thousand years is not understood well. This award supports a program of marine geologic research directed at filling this knowledge gap by developing an understanding of the dynamics of the northern Larsen Ice Shelf during the Holocene epoch (the last 10,000 years). The Larsen Ice Shelf is located in the NW Weddell Sea along the eastern side of the Antarctic Peninsula and is currently undergoing a rapid, catastrophic retreat as documented by satellite imagery over the past five years. While the region of the northern Antarctic Peninsula has experienced a pronounced warming trend over the last 40 years, the links between this warming and global change (i.e. greenhouse warming) are not obvious. Yet the ice shelf is clearly receding at a rate unprecedented in historic time, leaving vast areas of the seafloor uncovered and in an open marine setting. This project will collect a series of short sediment cores within the Larsen Inlet and in areas that were at one time covered by the Larsen Ice Shelf. By applying established sediment and fossil criteria to the cores we hope to demonstrate whether the Larsen Ice Shelf has experienced similar periods of retreat and subsequent advance within the last 10,000 years. Past work in various regions of the Antarctic has focused on depositional models for ice shelves that allow one to discern the timing of ice shelf retreat/advance in areas of the Ross Sea, Antarctic Peninsula, and Prydz Bay. This research will lead to a much improved understanding of the dynamics of ice shelf systems and their role in past and future climate oscillations.
The proposed project will expand the suite of observations and lengthen the existing time series of underway surface dissolved carbon dioxide (pCO2) measurements transects across the Drake Passage on the R/VIB L.M. Gould. The additional observations include oxygen, nutrients and total CO2 (TCO2) concentrations, and the 13C to 12C ratio of TCO2. The continued and expanded time series will contribute towards two main scientific goals: the quantification of the spatial and temporal variability and the trends of surface carbon dioxide species in four major water mass regimes in the Drake Passage, and the understanding of the dominant processes and changes in those processes that contribute to the variability in surface pCO2 and the resulting air-sea flux of CO2 in the Drake Passage. The expanded program will also include the analysis of the 14C/12C of TCO2 and the specific study of the observations on one short wintertime cruise, with the objective of testing the hypothesis that the dissolved carbon dioxide in surface waters of the Drake Passage is determined by the degree of winter mixing. This is of special significance in light of two scenarios that may be affecting the ventilation of Southern Ocean deep water now and in the future: a decrease in water column stratification with the observations of higher zonal winds, or an increase in stratification due to higher precipitation and warming from climate change. If winter mixing determines the mean annual pCO2 in the Drake Passage, the increasing trend in atmospheric pCO2 should have little effect on sea surface pCO2.
This project is an interdisciplinary study, titled Research on Ocean-Atmosphere Variability and Ecosystem Response in the Ross Sea (ROAVERRS), of atmospheric forcing, ocean hydrography, sea ice dynamics, primary productivity, and pelagic-benthic coupling in the southwestern Ross Sea, Antarctica. The primary goal is to examine how changes in aspects of the polar climate system, in this case wind and temperature, combine to influence marine productivity on a large antarctic continental shelf. In the Ross Sea, katabatic winds and mesocyclones influence the spatial and temporal distribution of sea ice as well as the upper ocean mixed layer depth, and thus control primary production within the sea ice as well as in the open water system. The structure, standing stock and productivity of bottom- dwelling biological communities are also linked to meteorological processes through interseasonal and interannual variations in horizontal and vertical fluxes of organic carbon produced in the upper ocean. Linkages among the atmospheric, oceanic, and biological systems will be investigated during a three-year field study of the southwestern Ross Sea ecosystem. Direct measurements will include regional wind and air temperatures derived from automatic weather stations; ice cover, ice movement, and sea surface temperatures derived from a variety of satellite-based sensors; hydrographic characteristics of the upper ocean and primary productivity in the ice and in the water derived from research cruises and satellite studies; vertical flux of organic material and water movement derived from oceanographic moorings containing sediment traps and current meters, and the abundance, distribution, and respiration rates of biological communities on the sea floor, derived from box cores, benthic photographs and shipboard incubations. Based on archived meteorological data, it is expected that the atmospheric variability during the study period will be such that changes in airflow pat terns and their influence on oceanographic and biological patterns can be monitored, and their direct and indirect linkages that are the focus of the research can be deduced. Results from this study will contribute to our knowledge of atmospheric and oceanic forcing of marine ecosystems, and lead to a better understanding of marine ecosystem response to climatic variations. ***
The krill surplus hypothesis argues that the near-extirpation of baleen whales from Antarctic waters during much the twentieth century led to significant changes in the availability of krill for other predators. Over the past decade, however, overall krill abundance has decreased by over an order of magnitude around the Antarctic Peninsula, in part due to physical forces, including the duration and extent of winter sea ice cover. Krill predators are vulnerable to variability in prey and have been shown to alter their demography in response to changes in prey availability This research will use novel tagging technology combined with traditional fisheries acoustics methods to quantify the prey consumed by a poorly understood yet ecologically integral and recovering krill predator in the Antarctic, the humpback whale (Megaptera novaeangliae). It also will use a combination of advanced non-invasive tag technology to study whale behavior concurrent with hydro-acoustic techniques to map krill aggregations. The project will (1) provide direct and quantitative estimates of krill consumption rates by humpback whales and incorporate these into models for the management of krill stocks and the conservation of the Antarctic marine ecosystem; (2) provide information integral to understanding predator-prey ecology and trophic dynamics, i.e., if/how baleen whales affect the distribution and behavior of krill and/or other krill predators; (3) add significantly to the knowledge of the diving behavior and foraging ecology of baleen whales in the Antarctic; and (4) develop new geospatial tools for the construction of multi-trophic level models that account for physical as well as biological data. <br/><br/>Broader Impacts: Whales are assumed to be a major predator on Antarctic krill, yet there is little understanding of how whales utilize this resource. This knowledge is critical to addressing both bottom-up and top-down questions, e.g., how climate change may affect whales or how whales may affect falling krill abundances. This program will integrate research and education by providing opportunities for undergraduate and graduate students as well as postdoctoral researchers at Duke University, the Florida State University and the University of Massachusetts at Boston. This project will also seek to integrate interactive learning through real time, seasonal and curriculum development in collaboration with the National Geographic Society as well as at the participating universities and local schools in those communities.
This proposed work concerns the development and maintenance of a shipboard acoustic Doppler current profiler (ADCP) program on board the RVIB Nathaniel B. Palmer and the research vessel Laurence M. Gould, operated by the United States Antarctic Program. The objective is to generate a quality-controlled data set on upper ocean current velocities in a sparsely sampled and remote region, yet one that plays an important role in the global ocean circulation. Further goals are to develop the underway data collection program so that it can be maintained with a minimum of personnel and resources, and that the observations become publicly available in a timely manner. Long-term science objectives are to measure the seasonal and interannual variability of upper ocean currents within the Drake Passage, to combine this information with similar temperature observations to study the variability in the heat exchange, and to characterize the velocity structure in the Southern Ocean on a variety of time and space scales.
9727077 SMITH The annual expansion and contraction of ice cover in the Southern Ocean is the largest seasonal process in the World Ocean. This seasonal variability in ice cover creates extensive fluctuations in primary production, which heavily impacts pelagic and benthic communities. This research will initiate a long time-series study of the water column and sea floor using long-term, autonomous monitoring and sampling systems developed for use in the Antarctic. The study will be located in Post Foster, Deception Island, which supports a pelagic and benthic fauna representative of the Antarctic coastal zone and experiences seasonal ice cover. A bottom-moored, upward-looking acoustic instrument will be deployed on the sea floor for a period of one year to monitor the vertical distribution, abundance and biomass of acoustically-detectable macrozooplankton and micronekton in the water column. Collections will be made over this period using a newly-developed vertically-profiling pump sampling. Simultaneously, a time-lapse camera system will be moored on the sea floor to monitor the spatial distribution, sizes and movements of the epibenthic megafauna component of the benthic community. The instrumentation development will allow the research project to focus on the effect of the seasonal sea ice cycle on the distribution, abundance and biomass of the macrozooplankton and micronekton in the water column. Similar questions on the distribution, abundance, size and movements of the epibenthic megafauna will be addressed. Results from this study will provide a valuable data base for the evaluation of the pelagic and benthic community responses to seasonal variability in the Southern Ocean.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). <br/><br/>This award supports a project to reconstruct the past physical and chemical climate of Antarctica, with an emphasis on the region surrounding the Ross Sea Embayment, using >60 ice cores collected in this region by US ITASE and by Australian, Brazilian, Chilean, and New Zealand ITASE teams. The ice core records are annually resolved and exceptionally well dated, and will provide, through the analyses of stable isotopes, major soluble ions and for some trace elements, instrumentally calibrated proxies for past temperature, precipitation, atmospheric circulation, chemistry of the atmosphere, sea ice extent, and volcanic activity. These records will be used to understand the role of solar, volcanic, and human forcing on Antarctic climate and to investigate the character of recent abrupt climate change over Antarctica in the context of broader Southern Hemisphere and global climate variability. The intellectual merit of the project is that ITASE has resulted in an array of ice core records, increasing the spatial resolution of observations of recent Antarctic climate variability by more than an order of magnitude and provides the basis for assessment of past and current change and establishes a framework for monitoring of future climate change in the Southern Hemisphere. This comes at a critical time as global record warming and other impacts are noted in the Southern Ocean, the Antarctic Peninsula, and on the Antarctic ice sheet. The broader impacts of the project are that Post-doctoral and graduate students involved in the project will benefit from exposure to observational and modeling approaches to climate change research and working meetings to be held at the two collaborating institutions plus other prominent climate change institutions. The results are of prime interest to the public and the media Websites hosted by the two collaborating institutions contain climate change position papers, scientific exchanges concerning current climate change issues, and scientific contribution series.
0538639<br/>Waddington<br/>This award supports a project to study the patterns of accumulation variation and microstructural properties near the WAIS Divide ice core site in a 2.5 km array of 20 m boreholes. Borehole Optical Stratigraphy (BOS) is a novel optical measurement system that detects annual-scale layers in firn that result from changes in firn microstructure, giving annual-scale records of how accumulation varied spatially over the last 40-50 years. Data from borehole optical stratigraphy can eventually be calibrated against other data on the microstructural parameters of firn to calibrate BOS's sensitivity to density, pore-volume, and pore-shape variations, and to show by proxy how these parameters vary in space across the survey area. Statistical analysis of layer-thickness and layer-brightness data will enable prediction of: 1) interannual accumulation variability, 2) variability in layer-thickness at decadal scales due to changing spatial patterns in accumulation and 3) variability in microstructure-driven metamorphism due to changing spatial patterns of microstructure. With these statistics in hand, a scientist measuring climatic shifts found in the WAIS Divide ice core will be able to determine the fraction by which signals they measure exceed the signal due to background accumulation variations. As an added benefit, while still in the field, we will determine a preliminary depth-age scale for the firn by optical layer-counting, to the depth of the deepest air-filled firn hole available. This will be a valuable result for core-drilling operations and for preliminary data-analysis on the core. In terms of broader impacts, this project will advance education by training a post-doctoral student in field techniques. The P.I. and the post-doctoral researcher will participate in an undergraduate seminar called "What is Scientific Research?", incorporating progress and results from this project. They will also communicate about their progress and field experience with a middle-school science and math class.
Abstract<br/><br/>The project goal is to investigate the ocean-atmosphere-ice (OAI) interactions in the Amundsen and Ross Seas during the austral summer of 2007-08 using hydrographic measurements (CTD and XBT) in conjunction with (1) ship-based observations and satellite-derived estimates of sea ice concentration, and (2) ship-based observations and re-analyses of meteorological variables. The major scientific objectives are as follows: (1) to examine upper ocean characteristics along three transects in the Amundsen Sea and two transects in the Ross Sea within the context of ice-atmosphere variability over the preceding winter-spring season and as compared to other years where data are available; (2) to determine if there is additional evidence of increased upwelling of warm Circumpolar Deep Water onto the shelf in the Amundsen Sea and/or increased freshening in the Ross Sea as has been inferred by previous, but limited, ocean surveys in these regions; and (3) to examine the spatial variability in ocean thermal structure along the ship's track (outside the transects) to provide greater regional context and to compare with ocean XBT data collected during Oden 2006-07. A repeated temperature survey between the Amundsen and Ross Sea is particularly invaluable, given that this sector is the regional center of the high latitude OAI response to ENSO, thus providing opportunity for examining and linking regional oceanic temporal variability to global climate variability. The research will improve our understanding of the high latitude OAI response to climate change, and provide the physical context for the observed biology and geochemistry (investigated by our colleagues. Our results will be made widely available through research publications and internet-available databases, and through the strong public outreach efforts of Lamont-Doherty Earth Observatory. The outreach efforts will help increase awareness and understanding of anthropogenic climate change, melting ice, and ecosystem alteration in the highly sensitive Antarctic.
This proposal is focused on experimental studies of the thunderstorms electrodynamic coupling to the Earth's radiation belts through the upward lightning flashes that lead to ionospheric parameters variability, and the global lightning effects on climate. The intellectual merit of the proposed program lies in the importance of the electrodynamic coupling of lightning discharges to the overlying ionosphere and the radiation belts, both in terms of lightning-induced electron precipitation, and in terms of high altitude optical and gamma-ray emissions produced by energy originating in lightning discharges. Precipitation of the radiation belt particles by whistler waves launched by lightning discharges will be measured as associated localized and transient disturbances of the lower ionosphere, which are sensed remotely by means of their effect on the phase and amplitude of very low frequency (VLF) signals propagating in the Earth-ionosphere waveguide. The broader impacts of the proposed research program will include the development of new technologies of lightning detection, with few observation sites and on a global scale, which can then be implemented for the benefit of society, both in terms of agriculture, navigation and other ways in which lightning and thunderstorms may affect human life. The proposed program is a part of the international collaboration between the Antarctic Peninsula stations, as well as complements a similar set of measurements that are conducted by the Stanford University in the northern hemisphere under support from other sources. Coordinated measurements in both hemispheres are needed to study the geomagnetic conjugacy of the observed phenomena.
0125794<br/>Price<br/><br/>This award supports research in climatology, geosciences, and life in extreme environments to be carried out with a newly developed optical borehole logger. The logger fits into a fluid-filled borehole in glacial ice. It emits light at 370 nm in a horizontal plane in order to probe optical properties of particles embedded in the ice out to several meters from the borehole. After leaving the borehole, the light is partially absorbed and scattered by dust, biomolecules, or microbes. A fraction of the light is scattered back into the borehole and is detected by a system of seven phototubes, each of which collects light with high efficiency in a separate wavelength band. One of them collects light that scatters off of dust and air bubbles without wavelength shift, and serves as a dust logger. The other six are covered with notch filters that measure six different wavelength bands and measure the shape of the fluorescence spectrum of microbes and biomolecules. Thus, the same instrument serves as both a dust logger and a microbe logger. Applications include: 1) Precise chronologies and long-period solar variability. With a resolution of 1 to 2 cm for both GISP2 and Siple Dome, the logger will record annual dust maxima and evaluate claims of modulations of dust concentration with periods ranging from 11 yrs (the solar cycle) to 2300 yrs; 2) Volcanism and age-depth markers. Dozens of volcanic ash bands will be detectable and will serve as primary age-depth markers for other boreholes; 3) Microorganisms and biomolecules. The vertical distribution of living, dormant, and dead microbes can be logged, and searches for archaea and aeolian polyaromatic hydrocarbons can be made. The logging experiments will be carried out at Siple Dome and Dome C in Antarctica and at GISP2 and GRIP in Greenland.
This project is an international collaborative investigation of geographic structuring, founding of new colonies, and population change of Adelie penguins (Pygoscelis adelia) nesting on Ross and Beaufort islands, Antarctica. The long-term changes occurring at these colonies are representative of changes throughout the Ross Sea, where 30% of all Adelie penguins reside, and are in some way related to changing climate. The recent grounding of two very large icebergs against Ross and Beaufort islands, with associated increased variability in sea-ice extent, has provided an unparalleled natural experiment affecting wild, interannual swings in colony productivity, foraging effort, philopatry and recruitment. Results of this natural experiment can provide insights into the demography and geographic population structuring of this species, having relevance Antarctic-wide in understanding its future responses to climate change as well as interpreting its amazingly well known Holocene history. This ongoing study will continue to consider the relative importance of resources that constrain or enhance colony growth (nesting habitat, access to food); the aspects of natural history that are affected by exploitative or interference competition among neighboring colonies (breeding success, foraging effort); climatic factors that influence the latter, especially sea ice patterns; and behavioral mechanisms that influence colony growth as a function of initial size and location (emigration, immigration). An increased effort will focus on understanding factors that affect over-winter survival. The hypothesis is that the age structure of Cape Crozier has changed over the past thirty years and no longer reflects the smaller colonies nearby. Based on recent analyses, it appears that the Ross Island penguins winter in a narrow band of sea ice north of the Antarctic Circle (where daylight persists) and south of the southern boundary of the Antarctic Circumpolar Current (where food abounds). More extensive winter ice takes the penguins north of that boundary where they incur higher mortality. Thus, where a penguin winters may be due to the timing of its post-breeding departure (which differs among colonies), which affects where it first encounters sea ice on which to molt and where it will be transported by the growing ice field. Foraging effort and interference competition for food suggested as factors driving the geographic structuring of colonies. The research includes a census of known-age penguins, studies of foraging effort and overlap among colonies; and identification of the location of molting and wintering areas. Information will be related to sea-ice conditions as quantified by satellite images. Demographic and foraging-effort models will be used to synthesize results. The iceberg natural experiment is an unparalleled opportunity to investigate the demographics of a polar seabird and its response to climate change. The marked, interannual variability in apparent philopatry, with concrete data being collected on its causes, is a condition rarely encountered among studies of vertebrates. Broader impacts include collaborating with New Zealand and Italian researchers, involving high school teachers and students in the fieldwork and continuing a website to highlight results to both scientists and the general public.
This proposal is to continue operation and scientific studies with the middle-frequency (MF, 1-30 MHz) mesospheric radar deployed at the British Antarctic station Rothera in 1996. This system is now a key site in the Antarctic MF radar chain near 68 deg. S, which includes also MF radars at Syowa (Japan) and Davis (Australia) stations. This radar comprises the winds component of a developing instrument suite for the mesosphere-thermosphere (MLT) studies at Rothera - a focus of the new BAS 5-year plan, which also includes the Fe temperature lidar (formerly at South Pole) and the mesopause airglow imager for gravity wave studies (formerly at Halley). The Rothera MF radar has just had its antennas and electronics upgraded to achieve better signal-to-noise ratio and more continuous measurements in height and time. The main focus of the proposed research is to extend the knowledge of the polar mesosphere dynamics. The instrument suite at Rothera is ideally positioned for correlative interhemispheric studies with northern hemisphere sites at Poker Flat, Alaska (65 deg. N) and ALOMAR, Norway (69 deg. N) having comparable instrumentation. Further research efforts performed with continued funding will focus on: (1) multi-instrument collaborative studies at Rothera to quantify as fully as possible the dynamics, structure, and variability of the MLT at that location, (2) multi-site (and multi-instrument) studies of large-scale dynamics and variability in the Antarctic (together with the radars and other instrumentation at Davis and Syowa), and (3) interhemispheric studies employing instruments (e.g., the Na resonance lidar and MF radar) at Poker Flat and ALOMAR. It is expected that these studies will lead to a more detailed understanding of (1) mean, tidal, and planetary wave structures at polar latitudes, (2) seasonal, inter-annual, and short-term variability of these structures, (3) hemispheric differences in the tidal and planetary wave structures arising from different source and wave interaction conditions, and (4) the relative influences of gravity waves in the two hemispheres. Such studies will also contribute more generally to an increased awareness of the role of high-latitude processes in global atmospheric dynamics and variability.
The Shackleton Fracture Zone (SFZ) in the Drake Passage defines a boundary between low and high phytoplankton waters. West of Drake Passage, Southern Ocean waters south of the Polar Front and north of the Antarctic continent shelf have very low satellite-derived surface chlorophyll concentrations. Chlorophyll and mesoscale eddy kinetic energy are higher east of SFZ compared to values west of the ridge. In situ data from a 10-year survey of the region as part of the National Marine Fisheries Service's Antarctic Marine Living Resources program confirm the existence of a strong hydrographic and chlorophyll gradient in the region. An interdisciplinary team of scientists hypothesizes that bathymetry, including the 2000 m deep SFZ, influences mesoscale circulation and transport of iron leading to the observed phytoplankton patterns. To address this<br/>hypothesis, the team proposes to examine phytoplankton and bacterial physiological states (including responses to iron enrichment) and structure of the plankton communities from virus to zooplankton, the concentration and distribution of Fe, Mn, and Al, and mesoscale flow patterns near the SFZ. Relationships between iron concentrations and phytoplankton characteristics will be examined in the context of the mesoscale transport of trace nutrients to determine how much of the observed variability in phytoplankton biomass can be attributed to iron supply, and to determine the most important sources of iron to pelagic waters east of the Drake Passage. The goal is to better understand how plankton productivity and community structure in the Southern Ocean are affected by the coupling between bathymetry, mesoscale circulation, and limiting nutrient distributions.<br/><br/>The research program includes rapid surface surveys of chemical, plankton, and hydrographic properties complemented by a mesoscale station grid for vertical profiles, water sampling, and bottle incubation enrichment experiments. Distributions of manganese and aluminum will be determined to help distinguish aeolian, continental shelf and upwelling sources of iron. The physiological state of the phytoplankton will be monitored by active fluorescence methods sensitive to the effects of iron limitation. Mass concentrations of pigment, carbon and nitrogen will be obtained by analysis of filtered samples, cell size distributions by flow cytometry, and species identification by microscopy. Primary production and photosynthesis parameters (absorption, quantum yields, variable fluorescence) will be measured on depth profiles, during surface surveys and on bulk samples from enrichment experiments. Viruses and bacteria will be examined for abundances, and bacterial production will be assessed in terms of whether it is limited by either iron or organic carbon sources. The proposed work will improve our understanding of processes controlling distributions of iron and the response of plankton communities in the Southern Ocean. This proposal also includes an outreach component comprised of Research Experiences for Undergraduates (REU), Teachers Experiencing the Antarctic and Arctic (TEA), and the creation of an educational website and K-12 curricular modules based on the project.
This project will provide for the continued operation and data analysis of an electro-optical remote sensing facility at South Pole Station. The facility will be used to examine 1) the source(s) and propagation of patches of enhanced plasma density in the F-region of the Antarctic ionosphere, 2) changes in the Antarctic E-region O/N2 ratio in the center of the night-sector of the auroral oval and compare the ratios with those found in the sun-aligned auroral arcs in the Polar Cap region, 3) Antarctic middle atmosphere disturbances generated by Stratospheric Warming Events (SWE), 4) quantitative characterization of the effects of solar variability on the temperature of the upper mesosphere region, 5) Antarctic thermospheric response to Solar Magnetic Cloud/Coronal Mass Ejection (SMC/CME) events, and 6) the effects of Joule heating on the thermodynamics of the Antarctic F-region. Data for all these studies will come from two sets of remote-sensing facilities at SPS: 1) Auroral emissions brightness measurements from the sun-synchronous Meridian Scanning Photon Counting Multichannel photometer; 2) Airglow and Auroral emission spectra recorded continuously during Austral winter at SPS with the high throughput, high resolution Infrared Michelson Interferometer as well as Visible - Near Infrared CCD spectrographs. <br/><br/>Meridional variations in the brightness of F-region's auroral emissions provide the necessary data for investigations of the dynamics and IMF control, as well as the excitation mechanism(s), of the F-region patches. The brightness of auroral emissions from O and N relative to those from molecular species (O2 and N2) can be analyzed to assess, quantitatively, changes in the thermospheric composition. These data (from continuous (24 hours a day) measurements during the totally dark six months of each Austral winter at SPS) will be used to investigate the effects of solar-terrestrial disturbances on Antarctic thermospheric composition and thermodynamics, including response of the mesopause to solar cycle variations. Changes in airglow temperature (derived from OH and O2 bands), from different mesosphere/lower-thermosphere (MLT) heights, permit studies of the dynamical effects of Planetary, Tidal and Gravity waves propagating in the MLT regions as well as non-linear interactions among these waves. Coupling of different atmospheric regions over SPS, through enhanced gravity wave activities during SWE that lead to a precursor as Mesospheric cooling, will be investigated through the observed changes in MLT kinetic air temperature and density. <br/><br/>The project will enhance the infrastructure for research and education at Embry-Riddle Aeronautical University, bringing together the PI/Co-I and students from Departments of Physical Sciences and Aerospace Engineering. Graduate and undergraduate students will participate in modern research and software development.
Saltzman/0636953<br/><br/>This award supports a project to measure methyl chloride, methyl bromide, and carbonyl sulfide in air extracted from Antarctic ice cores. Previous measurements in firn air and shallow ice cores suggest that the ice archive contains paleo-atmospheric signals for these gases. The goal of this study is to extend these records throughout the Holocene and into the last Glacial period to examine the behavior of these trace gases over longer time scales and a wider range of climatic conditions. These studies are exploratory, and both the stability of these trace gases and the extent to which they may be impacted by in situ processes will be assessed. This project will involve sampling and analyzing archived ice core samples from the Siple Dome, Taylor Dome, Byrd, and Vostok ice cores. The ice core samples will be analyzed by dry extraction, with gas chromatography/mass spectrometry with isotope dilution. The ice core measurements will generate new information about the range of natural variability of these trace gases in the atmosphere. The intellectual merit of this project is that this work will provide an improved basis for assessing the impact of anthropogenic activities on biogeochemical cycles, and new insight into the climatic sensitivity of the biogeochemical processes controlling atmospheric composition. The broader impact of this project is that there is a strong societal interest in understanding how man's activities impact the atmosphere, and how atmospheric chemistry may be altered by future climate change. The results of this study will contribute to the development of scenarios used for future projections of stratospheric ozone and climate change. In terms of human development, this project will support the doctoral dissertation of a graduate student in Earth System Science, and undergraduate research on polar ice core chemistry. This project will also contribute to the development of an Earth Sciences teacher training curriculum for high school teachers in the Orange County school system in collaboration with an established, NSF-sponsored Math and Science Partnership program (FOCUS).
This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit of the project. We plan to collect intermediate-length ice cores (100-200m) at four sites along transects in Taylor Valley and Wright Valley, and analyze each core at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). A suite of statistical techniques will be applied to the multivariate glaciochemical dataset to identify chemical associations and to calibrate the time-series records with available instrumental data. Broader impacts of the project include: 1) contributions to several ongoing interdisciplinary Antarctic research programs; 2) graduate and undergraduate student involvement in field, laboratory, and data interpretation activities; 3) use of project data and ideas in several UMaine courses and outreach activities; and 4) data dissemination through peer-reviewed publications, UMaine and other paleoclimate data archive websites, and presentations at national and international meetings.
This award supports a three year project to develop the tools required to interpret complex patterns of flow features on the Ross Ice Shelf, which record the discharge history the ice streams flowing east off of the West Antarctic Ice Sheet. This work builds on previous research that used flow features visible in satellite image mosaics and numerical models of ice shelf flow to detect changes in grounding zone dynamics and redirection of ice stream outlets over hundreds of years. Recently observed changes on Whillans Ice Stream fit within this framework. The pattern of redirection is driven by the influence of rapid downstream thinning on the basal thermal gradient in the ice and associated "sticky spot" (ice rise) formation. In pursuing this work, the investigators recognized other records of discharge variation on the shelf that can be used to build a more complete history and understanding of ice-stream discharge variability. The intellectual merit of the proposed work lies in the fact that these records, including fracture patterns and spatial variation in ice thickness, when understood in the proper context, will yield quantitative information about the timing and dynamics of ice stream slowdowns, grounding line retreat, and the relative history of discharge between the ice streams. New tools will help further constrain this history. The laser altimeter on NASA's IceSAT has improved our knowledge of the surface elevation of Antarctic ice. IceSAT surface elevations provide a high-resolution map of ice-shelf thickness that, along with provenance maps from ice-shelf image mosaics, will be used to estimate the volumes of ice involved in past ice-stream discharge events (slowdowns, redirections, and so on). This project will develop new numerical models for fracture propagation; these will allow past variations in ice-shelf stress state to be investigated. Together, the dynamic and volume-flux histories will provide a powerful set of observations for understanding past variations in ice stream discharge and the underlying physical processes. The broader impacts of this project center on how it contributes to the ability to estimate West Antarctic contributions to global sea level rise and to answer outstanding questions about the causes of millennial and longer-scale evolution of ice streams. This work will provide a history of the most complex record of ice discharge known. In addition to the incorporation of this research into graduate student advising and normal teaching duties, the investigators are involved in other avenues of civic engagement and education. Outreach to high school students and the community at large is promoted on an annual basis by the investigators at both institutions. New outreach projects at Portland State University are developed with the assistance of researchers with expertise in student learning and achievement in science and mathematics. The collaborative research team includes two glaciologists with experience in the pairing of high resolution satellite imagery and a variety of ice-flow models and a geologist whose focus is the mechanics of rock deformation.
0124049<br/>Berger<br/><br/>This award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.
The Antarctic Peninsula (AP) is characterized by (1) the most rapid recent regional (winter) warming (5.35 times global mean), (2) a loss of nearly all its perennial sea ice cover on its western margin, and (3) 87% of the glaciers in retreat, contributing to global sea level rise. An ability to understand this change depends upon researchers' ability to better understand the underlying sources of this change and their driving mechanisms. Despite intensive efforts, the western AP (WAP) is chronically under-sampled. Therefore developing a capability to maintain a sustained in situ presence is a high scientific priority. The current proposal addresses this critical need through 2 objectives: (1) establish the feasibility of a Slocum Webb ocean glider to enable real-time high resolution data-adaptive polar oceanographic research; (2) address a critical question involving the regional climate change by measuring the ocean heat budget within a grid containing 14 years of ship-based ocean snapshots. This will involve the launch of the glider during the PAL-LTER austral summer research cruise, where it will fly the full along-shore distance of the LTER sample grid to be recovered at the southern extreme when the ship arrives there later in the summer. The glider will provide nearly continuous ocean property (temperature, salinity and pressure) coverage over this distance.<br/><br/>Intellectual merit. The proposed activity will involve state of the art sampling methodology that will revolutionize the ability to address climate change and other scientific issues requiring sampling densities that could not be achieved by research vessels. Specifically, the adaptive sampling capability of the glider will be used to alter its course allowing identification of routes by which the source waters of the ocean heat (and nutrients) enter the continental shelf region, while the near-continuous sampling will provide a diagnosis of how well standard shipborne stations close the heat budget. Resources are adequate for this study due to heavy leveraging by the availability of the Rutgers SLOCUM Web glider, glider control center and participation of the team of experts that flew the first such glider.<br/><br/>Broader Impacts. The proposed activity will advance discovery and understanding of the WAP responses to climate variability, to study the intricate feedback mechanisms associated with this variability and to better understand the chemical and physical processes associated with climate change. The data will be made available across the World Wide Web as it is collected, almost in real time, a potential bonanza for scientists during the upcoming International Polar Year, for classroom instruction and general outreach. Society will ultimately benefit from the improved knowledge of how climate change elsewhere in the world is impacting the unique ecosystem of the Antarctic, and driving glacial melt (sea level rise), among its other influences.
This award supports a project to use three downhole instruments - an optical logger; a<br/>miniaturized biospectral logger at 420 nm (miniBSL-420); and an Acoustic TeleViewer (ATV) - to log a 350-m borehole at the WAIS Divide drill site. In addition, miniBSL-224 (at 224 nm) and miniBSL-420 will scan ice core sections at NICL to look for abrupt climate changes, volcanic ash, microbial concentrations, and correlations among them. Using the optical logger and ATV to log bubble number densities vs depth in a WAIS Divide borehole, we will detect annual layers, from which we can establish the age vs depth relation to the bottom of the borehole that will be available during the three-year grant period. With the same instruments we will search for long-period modulation of bubble and dust concentrations in order to provide definitive evidence for or against an effect of long-period variability of the sun or solar wind on climate. We will detect and accurately date ash layers in a WAIS Divide borehole. We will match them with ash layers that we previously detected in the Siple Dome borehole, and also match them with sulfate and ash layers found by others at Vostok, Dome Fuji, Dome C, and GISP2. The expected new data will allow us to extend our recent study which showed that the Antarctic record of volcanism correlates with abrupt climate change at a 95% to >99.8% significance level and that the volcanic signatures at bipolar locations match at better than 3 sigma during the interval 2 to 45 kiloyears. The results to be obtained during this grant period will position us to extend an accurate age vs depth relation and volcano-climate correlations to earlier than 150 kiloyears ago in the future WAIS Divide borehole to be drilled to bedrock. Using the miniBSLs to identify biomolecules via their fluorescence, we will log a 350-m borehole at WAIS Divide, and we will scan selected lengths of ice core at NICL. Among the biomolecules the miniBSLs can identify will be chlorophyll, which will provide the first map of aerobic microbes in ice, and F420, which will provide the first map of methanogens in ice. We will collaborate with others in relating results from WAIS Divide and NICL ice cores to broader topics in climatology, volcanology, and microbial ecology. We will continue to give broad training to undergraduate and graduate students, to attract underrepresented minorities to science, engineering, and math, and to educate the press and college teachers. A deeper understanding of the causes of abrupt climate change, including a causal relationship with strong volcanic eruptions, can enable us to understand and mitigate adverse effects on climate.
Satellite-tracked drifters provide simple yet powerful tools to track the motion of near-surface water on time scales ranging from the tidal/inertial band to monthly and longer. The research described herein will deploy satellite-tracked surface drifters during the annual austral summer Palmer Long Term Ecological Research (LTER) cruises in January 2006 and 2007 in order to investigate the nearsurface Lagrangian currents over the western Antarctic Peninsula (wAP) shelf. This region is experiencing the highest surface air temperature increase (roughly +0.06 degrees C per year) in Antarctica, and LTER and other investigators have found that ecosystem responses to the rapid warming and sea ice decline are already apparent at all trophic levels from phytoplankton to penguins. Building a better understanding of the regional circulation and its variability seems an essential component to understand existing physical and biological processes and longer-term changes in this important and sensitive Antarctic ecosystem. These new Lagrangian measurements will complement those made during the 2001-2003 U.S. Southern Ocean (SO) GLOBEC program and provide the first detailed look at the near-surface flow in this important section of the wAP shelf. In particular, the combined 3-year LTER Lagrangian measurements should identify (a) the source region(s) of the buoyant coastal current discovered flowing southwest along the outer coast of Adelaide Island and into Marguerite Bay during SO GLOBEC and (b) if organized cross-shelf flows occur that help create a two gyre circulation over the shelf as suggested by Hofmann et al (1996) based on regional hydrography. The principal investigators will process and analyze the LTER 2005-2007 drifter data and collaborate with Palmer LTER investigators on the interpretation and integration of the Lagrangian data with their studies. The edited data, analysis results, and animations of the drifter data with surface weather data will be posted on the LTER website for use and viewing by scientists, students, and the public. Results will be presented at national meetings and published in referred journals.
This award supports the development of a new laboratory capability in the U.S. to measure CO2 in ice cores and investigate millennial-scale changes in CO2 during the last glacial period using samples from the Byrd and Siple Dome ice cores. Both cores have precise relative chronologies based on correlation of methane and the isotopic composition of atmospheric oxygen with counterpart records from Greenland ice cores. The proposed work will therefore allow comparison of the timing of CO2 change, Antarctic temperature change, and Greenland temperature change on common time scales. Such comparisons are vital for evaluating models that explain changes in atmospheric CO2. The techniques being developed will also be available for future projects, specifically the proposed Inland WAIS ice core, for which a highly detailed CO2 record is a major objective, and studies greenhouse and other atmospheric gases and their isotopic composition for which dry extraction is necessary (stable isotopes in CO2, for example). There are many broad impacts of the proposed work. Ice core greenhouse gas records are central contributions of paleoclimatology to research and policy-making concerning global change. The proposed work will enhance those contributions by improving our understanding of the natural cycling of the most important greenhouse gas. It will contribute to the training of a postdoctoral researcher, who will be an integral part of an established research group and benefit from the diverse paleoclimate and geochemistry community at OSU. The PI teaches major and non-major undergraduate and graduate courses on climate and global change. The proposed work will enrich those courses and the courses will provide an opportunity for the postdoctoral researcher to participate in teaching by giving guest lectures. The PI also participates in a summer climate workshop for high school teachers at Washington State University and the proposed work will enrich that contribution. The extraction device that is built and the expertise gained in using it will be resources for the ice core community and available for future projects. Data will be made available through established national data center and the equipment designs will also be made available to other researchers.
This award supports a comprehensive investigation of the spatial and temporal characteristics of the surface mass balance of the Antarctic ice sheet and the governing mechanisms that affect it. A mesoscale atmospheric model, adapted for Antarctic conditions (Polar MM5), will be used in conjunction with the newly available reanalysis from the European Centre for Medium-Range Weather Forecasts (ECMWF) to resolve the surface mass balance of Antarctica at a time resolution of 3 hours and a spatial resolution of 60 km from 1957 to 2001. Polar MM5 will be upgraded to account for key processes in the simulation, including explicit consideration of blowing snow transport and sublimation as well as surface melting/runoff. The proposed 45-y hindcast of all Antarctic surface mass balance components with a limited area model has not previously been attempted and will provide a dataset of unprecedented scope to complement existing ice core measurements of recent climate, especially those collected by the International Transantarctic Scientific Expedition (ITASE). The trends and variability in space and time over 4.5 decades will be resolved and the impact of the dominant modes of atmospheric variability (Antarctic Oscillation, El Nino-Southern Oscillation, etc.) will be isolated. Hypotheses concerning the Antarctic surface mass balance response to climate change will be tested. The research will provide a sound basis for evaluating the impact of future climate change on Antarctic surface mass balance and its contribution to global sea level change as well as providing an important perspective for the interpretation of Antarctic ice core records. The broader impacts include the education of a Ph.D. student, the development of material for use in university classes, and construction of an interactive educational webpage on Antarctic surface mass balance.
Major portions of the Antarctic Ice Sheet float in the surrounding ocean, at the physical and intellectual boundaries of oceanography and glaciology. These ice shelves lose mass continuously by melting into the sea, and periodically by the calving of icebergs. Those losses are compensated by the outflow of grounded ice, and by surface accumulation and basal freezing. Ice shelf sources and sinks vary on several time scales, but their wastage terms are not yet well known. Reports of substantial ice shelf retreat, regional ocean freshening and increased ice velocity and thinning are of particular concern at a time of warming ocean temperatures in waters that have access to deep glacier grounding lines.<br/>This award supports a study of the attrition of Antarctic ice shelves, using recent ocean geochemical measurements and drawing on numerical modeling and remote sensing resources. In cooperation with associates at Columbia University and the British Antarctic Survey, measurements of chlorofluorocarbon, helium, neon and oxygen isotopes will be used to infer basal melting beneath the Ross Ice Shelf, and a combination of oceanographic and altimeter data will be used to investigate the mass balance of George VI Ice Shelf. Ocean and remote sensing observations will also be used to help refine numerical models of ice cavity circulations. The objectives are to reduce uncertainties between different estimates of basal melting and freezing, evaluate regional variability, and provide an update of an earlier assessment of circumpolar net melting.<br/>A better knowledge of ice shelf attrition is essential to an improved understanding of ice shelf response to climate change. Large ice shelf calving events can alter the ocean circulation and sea ice formation, and can lead to logistics problems such as those recently experienced in the Ross Sea. Broader impacts include the role of ice shelf meltwater in freshening and stabilizing the upper ocean, and in the formation of Antarctic Bottom Water, which can be traced far into the North Atlantic. To the extent that ice shelf attrition influences the flow of grounded ice, this work also has implications for ice sheet stability and sea level rise.
This award supports a project to develop computational models to simulate ice-shelf rift propagation using a combination of well-established ice-shelf creep-flow models and new crevasse models, based on linear elastic fracture mechanics (LEFM). The overall objective of the proposed work is to simulate rift propagation and eventual large iceberg calving,and place those processes within a larger ice sheet and climate context. The work will proceed in stages, first developing models of single-and multiple-crevasse propagation; then using those models to evaluate propagation sensitivity to various environmental conditions; and third developing models that incorporate both crevasse propagation and advection within an ice- shelf system. Model development will be guided by and evaluated according to satellite observations of rift propagation in several characteristic locations on Antarctic ice shelves. New numerical models of fracture in ice will have applications to many problems in glaciology. The research proposed here is directed toward large rift formation in ice shelves and subsequent iceberg calving. It is motivated by the need to understand observed changes in modern ice shelves,and their connection to climate. Where it has been sampled, the sedimentary record of the Weddell Sea sector implies Peninsular ice shelf variability on millennial time scales. The ability to simulate iceberg calving in a credible way will improve our ability to reproduce such events and place the complete cycle of ice shelf advance and retreat in an ice-dynamics context. That will, in turn, enable us to place ice-shelf cycles within the climate cycles that ultimately drive ice-sheet mass balance.
This award supports a science management office for a pilot ice-core drilling and analysis program to test the feasibility of obtaining well-dated, high-resolution isotope and chemistry records from East Antarctica. Shallow ice cores will be obtained from two locations: 1) ~100 km from South Pole towards the Pole of Inaccessibility, as an extension of the Byrd Station-to-South Pole ITASE traverse [International Trans Antarctic Scientific Expedition]; 2) at Taylor Dome, near the original deep coring site, and (3) possibly at AGO 3 and AGO 4 as part of a logistics traverse to these sites. All of the cores collected will be sampled at very high resolution (~1/2 cm) and analyzed for major ions. Results from this calibration work, along with those from another project that is analyzing stable isotopes will be used to help plan a program of larger scope, with the objective of mapping the spatial expression of climate variability in East Antarctica. Funds are also provided to organize a community workshop for coordination of the second phase of US ITASE and for one workshop per year for two years dedicated to writing and preparation of scientific papers from phase one of US ITASE. In addition, route selection activities for the follow-on traverse activities in East Antarctica will be conducted using satellite image mapping. A summary document will be produced and made available to the community to help with planning of related field programs (e.g. deep ice radar, firn radar profiling, atmospheric chemistry, ice coring, snow surface properties for satellite observations, ice surface elevation and mass balance).
Ice streams are believed to play a major role in determining the response of their parent ice sheet to climate change, and in determining global sea level by serving as regulators on the fresh water stored in the ice sheets. Ice streams are characterized by rapid, laterally confined flow which makes them uniquely identifiable within the body of the more slowly and more homogeneously flowing ice sheet. But while these characteristics enable the identification of ice streams, the processes which control ice-stream motion and evolution, and differences among ice streams in the polar regions, are only partially understood. Understanding the relative importance of lateral and basal drags, as well as the role of gradients in longitudinal stress, is essential for developing models for future evolution of the polar ice<br/>sheets. In this project, physical statistical models will be used to explore the processes that control ice-stream flow, and to compare these processes between seemingly different ice-stream systems. In particular, Whillans Ice Stream draining into the Ross Ice Shelf, will be compared with Recovery and RAMP glaciers draining into the Ronne-Filchner Ice Shelf, and the Northeast Ice Stream in Greenland. Geophysical models lie at the core of the approach, but are embellished by modeling various components of variability statistically. One important component comes from the uncertainty in observations on basal elevation, surface elevation, and surface velocity. In this project new observational data collected using remote-sensing techniques will be used. The various components, some of which are spatial, are combined hierarchically using Bayesian statistical methodology. All these components will be combined mathematically into a physical statistical model that yields the posterior distribution for basal, longitudinal, and lateral stress fields, and velocity fields, conditional on the data. Inference based on this distribution will be carried out via Markov chain Monte Carlo techniques, to obtain estimates of these unknown fields along with uncertainty measures associated with them.
Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.
Kanagaratnam, Pannirselvam; Braaten, David; Bauer, Rob
No dataset link provided
This award supports a project to build and test a 12-18 GHz radar system with a plane wave antenna. This is a wideband radar operating over a frequency range of 12 to 18 GHz to detect near-surface internal firn layers of the ice sheet with better than 10 cm resolution to a depth of approximately 7 m. These measurements will allow determination of spatially continuous snow accumulation rate in the firn, which would be useful along a traverse and is of critical importance to the validation of CryoSat and ICESAT satellite missions aimed at assessing the current state of mass balance of the polar ice sheets. The antenna system planned for the radar is relatively compact, and will be located on the sledge carrying the radar systems. The broad scientific focus of this project will be to investigate important glacial processes relevant to ice sheet mass balance. The new radar will allow the characterization (with high depth resolution) of the spatial variability of snow accumulation rate along a traverse route for interpreting data from CryoSat and ICESAT missions. As part of this project, we will institute a strong outreach program involving K-12 education and a minority institution of higher education. We currently work closely with the Advanced Learning Technology Program (ALTec) at the University of Kansas to develop interactive, resource-based lessons for use on-line by students of all grade levels, and we will develop new resources related to this project. We currently have an active research and education collaboration with faculty and undergraduate students at neighboring Haskell Indian Nations University, in Lawrence, Kansas, and we will expand our collaboration to include this project.
This award supports the analysis, in Antarctic ice cores, of the ozone depleting substances methyl bromide (CH3Br) and methyl chloride (CH3Cl), and the sulfur-containing gas, carbonyl sulfide (OCS). The broad scientific goal is to assess the level and variability of these gases in the preindustrial atmosphere. This information will allow testing of current models for sources and sinks of these gases from the atmosphere, and to indirectly assess the impact of anthropogenic activities on their biogeochemical cycles. Longer-term records will shed light on the climatic sensitivity of the atmospheric burden of these gases, and ultimately on the biogeochemical processes controlling them. These gases are present in ice at parts per trillion levels, and the current database consists entirely of a small number of measurements made in from a shallow ice core from Siple Dome, Antarctica. This project will involve studies of ice core samples from three Antarctic sites: Siple Station, Siple Dome, and South Pole. The sampling strategy is designed to accomplish several objectives: 1) to verify the atmospheric mixing ratios previously observed in shallow Siple Dome ice for OCS, CH3Br, and CH3Cl at sites with very different accumulation rates and surface temperatures; 2) to obtain a well-dated, high resolution record from a high accumulation rate site (Siple Station), that can provide overlap in mean gas age with Antarctic firn air samples; 3) explore Holocene variability in trace gas mixing ratios; and 4) to make the first measurements of these trace gases in Antarctic glacial ice. In terms of broader impact on society, this research will help to provide a stronger scientific basis for policy decisions regulating the production and use of ozone-depleting and climate-active gases. Specifically, the methyl bromide results will contribute to the current debate on the impact of recent regulation (via the Montreal Protocol and its Amendments) on atmospheric levels. Determination of pre-industrial atmospheric variability of ozone-depleting substances will help place more realistic constraints on scenarios used for future projections of stratospheric ozone and its climatic impacts. This research will involve the participation of both graduate and undergraduate students.
Roy, Martin; Hemming, Sidney R.; Goldstein, Steven L.; Van De Flierdt, Christina-Maria
No dataset link provided
This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the sediment core from the Southern Ocean for paleoenvironmental research. The polar regions are susceptible to the largest changes in climate and are among the least accessible places on Earth. Current concern about the instability of the West Antarctic Ice Sheet has heightened awareness of the vulnerability of polar regions. This proposal seeks to gain a basic understanding of the isotopic characteristics of terrigenous sediment sources derived from Antarctica in the Holocene and Last Glacial Maximum, and their dispersal into the Southern Ocean. Terrigenous clastic sediments are brought to the ocean from continental sources via rivers, ice and wind, and distributed within the ocean by surface and deep currents. At present there are virtually no isotopic data on circumpolar detritus, save a few strontium (Sr) isotopic ratios in the Atlantic sector. This project will fill part of this gap. From the large range in geological ages of crustal provinces of Antarctica, we would predict that there are large isotopic differences in detritus around the continent. The main objectives are to (1) characterize the strontium-neodymium-lead-argon (Sr-Nd-Pb-Ar) isotope compositions of sediment sources derived from Antarctica, (2) to identify the composition and source ages of major ice rafted detritus (IRD) contributions by analyzing individual grains of hornblende and feldspar in conjunction with bulk isotopic analysis, and (3) track sediment dispersal into the Antarctic Circumpolar Current (ACC) during the Holocene and Last Glacial Maximum.<br/><br/>Because of the paucity of circumpolar data, this research necessarily has a large exploratory component. Consequently, it will provide a basic database for future studies. Nevertheless there are important hypothesis-driven questions that will be addressed in this primary pass. Can lessons learned in North Atlantic IRD studies be applied toward understanding the history of Antarctic ice sheets? Can the large geological variability around the Antarctic margin be treated as a series of natural tracer injections into the ACC, and thus characterize its trajectory, speed, and interaction with other current systems today and in the past? The proposed study is motivated by an exciting set of results from the South Atlantic, showing that detrital Sr isotope ratios are a sensitive current tracer in that region. This research should serve a basic need across many Earth Science disciplines if the use of long-lived radiogenic isotopes (Sr-Nd-Pb-Ar) as tracers of marine sediment sources is successful in elucidating processes related to changing climatic conditions. The results of this study will fill a basic gap in our knowledge of an important region of the Earth. At the same time, it will provide an essential basis for attempting reconstruction of the ACC during the LGM, as well as for future studies of Antarctic geology, ice sheet history, and the Southern Ocean circulation.
This award is for support for a program to make high resolution studies of variations in the concentration of methane, the oxygenisotope composition of paleoatmospheric oxygen, and the total gas content of deep Antarctic ice cores. Studies of the concentration and isotopic composition of air in the firn of the Antarctic ice sheet will also be continued. One objective of this work is to use the methane concentration and oxygen-isotope composition of oxygen of air in ice as time-stratigraphic markers for the precise intercorrelation of Greenland and Antarctic ice cores as well as the correlation of ice cores to other climatic records. A second objective is to use variations in the concentration and interhemispheric gradient of methane measured in Greenland and Antarctic ice cores to deduce changes in continental climates and biogeochemistry on which the atmospheric methane distribution depends. A third objective is to use data on the variability of total gas content in the Siple Dome ice core to reconstruct aspects of the glacial history of West Antarctica during the last glacial maximum. The fourth objective is to participate in collaborative studies of firn air chemistry at Vostok, Siple Dome, and South Pole which will yield much new information about gas trapping in ice as well as the concentration history and isotopic composition of greenhouse gases, oxygen, trace biogenic gases and trace anthropogenic gases during the last 100 years.
9316564 Mayewski This award is for support for a three year program to provide a high resolution record of the Antarctic climate through the acquisition, analysis, and interpretation of records of atmospheric chemical deposition taken from three ice cores located at sites within or immediately adjacent to the Ross Ice Drainage System (RIDS). These cores include one from Taylor Dome, and two from West Antarctic locations identified as potential deep drilling sites for the WAISCORES program. Collection of the two West Antarctic cores is intended to be a lightweight dry-drilling operation to depths of ~ 200 m, which will provide records of > 2 kyr. Glaciochemical analyses will focus on the major cations and anions found in the antarctic atmosphere, plus methanesulfonic acid and selected measurements of the hydrogen ion, aluminum, iron, and silica. These analyses, and companion stable isotope and particle measurements to be carried out by other investigators require < 7% by volume of each core, leaving > 90% for other investigators and storage at the U.S. National Ice Core Laboratory. These records are intended to solve a variety of scientific objectives while also providing spatial sampling and reconnaissance for future U.S. efforts in West Antarctica. ***
This award is for support for four years of funding for a program of biogenic sulfur measurements on the Siple Dome ice core. Biogenic sulfur is a major aerosol-forming constituent of the atmosphere and has potentially important links to the earth's radiation budget. Previous work on the Vostok ice core has demonstrated a remarkable climate-related variability in biogenic sulfur, suggesting that the sulfur cycle may act to stabilize climate (keep the glacial atmosphere cool and the interglacial atmosphere warm) in the Southern Hemisphere. In this study, methane-sulfonate (MSA) will be measured on the Siple Dome ice core as part of the West Antarctic ice sheet program (WAIS). Siple Dome is located in a region which is strongly impacted by the incursion of marine air onto the Antarctic plateau. Because of its proximity to the coast and meteorological setting, it is expected that variability in high-latitude marine biogenic sulfur emissions should dominate the MSA record at this site. In addition to the deep ice core record, samples from shallow cores will also be analyzed to provide information about regional variability and decadal-to-centennial scale variability in the deposition of sulfur-containing aerosols from high latitude source regions over the past 200 years.
This award is for support for the measurement of electrical and optical properties of the Siple Dome ice core. The electrical methods can be used to determine the concentration of the hydrogen ions and the concentration of a weighted sum of all ions. The electrical measurements can resolve features as small as 1 cm. The albedo of the core is also measured with a laser system that can resolve features as small as 0.5 cm. The high spatial resolution of these methods makes them ideal for resolving narrow features in the core, which can be missed in larger composite samples. The measurements will be particularly useful for assisting to date the core and to identify short duration features in the record, such as volcanic eruptions. These measurements will also provide useful information for assessing the temporal variability of Holocene accumulation rate and atmospheric circulation.
This award is for support for a program of glaciochemical analyses of shallow and deep ice cores from Siple Dome, West Antarctica. Measurements that have been proposed include chloride, nitrate, sulfate, calcium, magnesium, sodium, potassium, ammonium and methansulfonic acid. These measurements will provide information about past volcanic events, biomass source strength, sea ice fluctuations, atmospheric circulation, changes in ice-free areas and the environmental response to Earth orbit insolation changes and solar variability. The glaciochemical records from the Siple Dome core will be developed at a resolution sufficient to compare with the Summit, Greenland record, thus allowing a bipolar comparison of climate change event timing and magnitude. As part of this award, an international workshop will be held during the first year to formulate a science plan for the International Transantarctic Scientific Expedition (ITASE), a program of regional surveys documenting the spatial distribution of properties measured in ice cores .
9530379 Anderson This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. This work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three- year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This component is a study of how naturally radioactive material in the ocean sediment may be used to reconstruct the flux of biogenic material through the water column to the sediment, and by inference, the productivity of the surface layers. There is evidence that the current surface conditions of high nutrient levels, but low chlorophyll levels do not extend back into colder climatic epochs, and that an examination of radionuclides may allow the reconstruction of rates of paleoproductivity. Two aspects of the biogeochemical cycling and physical transport of radionuclide tracers in the modern ocean will be investigated. In the first part, the concentration of a series of natural radionuclide tracers (thorium-230, protactinium-231, and Beryllium-10) in the Southern Ocean will be measured for their scavenging behavior both in the water column and in particulate material collected by sediment traps. The goal is to test the proposed use of radionuclide ratios as proxy variables for the export flux. In the second part, the concentration values will be introduced into an ocean general circulat ion model to evaluate the transport of radionuclides by the ocean circulation on scales that are larger than the spatial gradients in particle flux. These combined efforts will better define our ability to use radionuclide ratios to evaluate past changes in ocean productivity, and improve our understanding of the response of ocean productivity to climate variability. ***