{"dp_type": "Project", "free_text": "biogeochemical"}
[{"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.\u003cbr/\u003e\u003cbr/\u003eThis 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.", "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": null, "bounds_geometry": null, "dataset_titles": "Deuterium isotopic composition of atmospheric methane across Dansgaard Oesgher Event 8, Talos Dome Ice Core, Antarctica", "datasets": [{"dataset_uid": "601814", "doi": "10.15784/601814", "repository": "USAP-DC", "science_program": null, "title": "Deuterium isotopic composition of atmospheric methane across Dansgaard Oesgher Event 8, Talos Dome Ice Core, Antarctica", "url": "http://www.usap-dc.org/view/dataset/601814"}], "date_created": "Tue, 23 Jul 2024 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Abrupt Climate Change; Antarctica; Biogeochemical Cycles; Carbon Cycle; Cryosphere; Ice Core Records; Talos Dome", "locations": "Antarctica; Talos Dome", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Riddell-Young, Benjamin; Brook, Edward J.; Iseli, Rene; Lee, James; Schmitt, Jochen; Fischer, Hubertus; Bauska, Thomas; Menking, James; Clark, Reid", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "2207011 Granger, Julie", "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": "Mon, 04 Mar 2024 00:00:00 GMT", "description": "Iron is a limiting nutrient for primary production in 30% of the global ocean, including the Southern Ocean. Dinoflagellates thrive in a wide variety of coastal and oceanic environments, including iron-limited regions. As iron is a biologically essential element for the growth and proliferation of marine algae, dinoflagellates may have evolved strategic mechanisms to combat iron limitation. Presently, these mechanisms have been scantly investigated in dinoflagellates. Here, we compare the growth response of the well-studied diatom Thalasiossira weissflogii to that of dinoflagellates Amphidinium carterae, Heterocapsa triquetra, and Symbiodinium tridacnidorum to different iron conditions: (a) iron-replete medium, (b) iron-limited medium, and (c) iron-limited medium supplemented with the siderophore Deferoxamine B (DFB). Preliminary observations suggest that A. carterae is able to assimilate iron bound to DFB, in contrast to T. weissflogii and Heterocapsa triquetra. A survey of the transcriptome of A. carterae suggests that it possess genes analogous to the TonB-dependent receptors (TBDRs) associated with iron-siderophore transport in prokaryotes. Additional species of dinoflagellates will be observed to investigate the ubiquity of this strategy in dinoflagellates. A more comprehensive understanding of dinoflagellate acclimation to low iron conditions is key to understanding their ecophysiology and the biogeochemical dynamics of iron-limited regions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Dinoflagellates; Iron; United States Of America; Iron Acquisition; Siderophore; TRACE ELEMENTS; Iron Limitation", "locations": "United States Of America", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Granger, Julie; Lin, Senjie", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Siderophore utilization by dinoflagellates as a strategy for iron acquisition", "uid": "p0010455", "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": "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\u0027s 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.", "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": "2032328 Apel, 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": null, "datasets": null, "date_created": "Thu, 27 Jul 2023 00:00:00 GMT", "description": "A class of small molecules, very short-lived substances (VSLS; e.g. CHBr3,CH2Br2, and CH3I) are important components in the climate system where they act as tropospheric ozone destroyers as described in the multilateral environmental Montreal Protocol on Substances that Deplete the Ozone Layer. The Southern Ocean represents a key component in the climate system and has a critical role in other global biogeochemical cycles.\r\n\r\nThis project will use the NSF/NCAR Community Earth System Model (CESM) with a newly developed online air-sea exchange framework, to evaluate biogeochemical controls on the marine sources of VSLS in the Southern Ocean as well as the Southern Hemisphere. A machine-learning approach will be used to couple ocean biogeochemistry with air-sea exchange for these compounds. A variety of oceanic and atmospheric observations of VSLS will be used to evaluate a unique oceanic VSLS inventory. In particular, the recent ORCAS field campaign provides a unique opportunity to examine Southern Ocean VSLS emissions, and their impacts from ocean biogeochemistry, meteorology and sea ice cycles. The project will also support a postdoctoral early-career researcher, and a specific effort of this project is STEM education and public outreach activities. The research team will extend opportunities to high school and undergraduate students so they may gain experience in the coupled ocean and atmospheric sciences, including exposure to and experience in programming and modeling.\r\n\r\nThis 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": "Antarctic Peninsula; HALOCARBONS AND HALOGENS", "locations": "Antarctic Peninsula", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Apel, Eric", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Southern Ocean Biogeochemistry Control on Short-Lived Ozone-Depleting Substances and Impacts on the Climate System", "uid": "p0010427", "west": -180.0}, {"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": "The aims of this CAREER proposal are to gain a greater understanding of the role of sympagic algae in Antarctic marine ecosystems with the goal to better parameterize their role in biogeochemical and ecosystem processes across dynamic environments. Specifically, this proposal will apply a laboratory-scale, ice-tank system that recreates the seasonal cycle of sea ice in the laboratory for the purpose of studying sympagic microbes to study the following questions:\r\n1.1 \tStarting with a late autumn, mixed phytoplankton community, how do different algal species specialize to sea ice, seawater and flooded snow/ice habitats over winter?\r\n1.2 \tWhat are the relationships between different methods of measuring primary production (fluorescence, O2 production, CO2 drawdown) in sea ice? Does this differ from seawater?\r\n1.3 \tDoes the presence of sea-ice algae influence the physical structure of sea ice?\r\n1.4\tHow does the release of compatible solutes from algae during ice melt influence the dissolved organic pool?\r\nIn addition, I propose to integrate educational activities with my research goals. This includes development of an educational program at the university and K-12 level on Antarctic Sciences that develops critical thinking and quantitative skills, encourages STEM participation from underrepresented groups and establishes an interactive network of Antarctic researchers to broaden research opportunities.\r\n", "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 Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences", "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": "2026045 Schofield, Oscar; 2224611 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": "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.\r\n\r\nPolar 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 Nio Southern Oscillation and Southern Annular Mode) are being studied at multiple time scales from diel, seasonal, interannual, to decadal intervals, and space scalesfrom 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.", "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": "1745078 Brook, Edward J.", "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": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ; Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation; Carbon-13 and Deuterium isotopic composition of atmospheric methane across Heinrich Stadial 4, and Dansgaard Oesgher Event 8, WAIS Divide Replicate Ice Core, Antarctica; Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "datasets": [{"dataset_uid": "601813", "doi": "10.15784/601813", "keywords": "Abrupt Climate Change; Antarctica; Atmospheric Gases; Biogeochemical Cycles; Carbon Cycle; Cryosphere; Greenhouse Gas; Methane; West Antarctic Ice Sheet Divide", "people": "Fischer, Hubertus; Bauska, Thomas; Menking, Andy; Iseli, Rene; Brook, Edward J.; Clark, Reid; Lee, James; Riddell-Young, Benjamin; Schmitt, Jochen", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Carbon-13 and Deuterium isotopic composition of atmospheric methane across Heinrich Stadial 4, and Dansgaard Oesgher Event 8, WAIS Divide Replicate Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601813"}, {"dataset_uid": "601737", "doi": "10.15784/601737", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Greenland; Ice Core Records; Methane; West Antarctic Ice Sheet", "people": "Brook, Edward J.; Edwards, Jon S.; Lee, James; Rosen, Julia; Martin, Kaden; Riddell-Young, Benjamin", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ", "url": "https://www.usap-dc.org/view/dataset/601737"}, {"dataset_uid": "601736", "doi": "10.15784/601736", "keywords": "Antarctica; Greenland; Methane; Paleoclimate; West Antarctic Ice Sheet", "people": "Fischer, Hubertus; Brook, Edward J.; Riddell-Young, Benjamin; Rosen, Julia; Buizert, Christo; Martin, Kaden; Lee, James; Edwards, Jon S.; M\u00fchl, Michaela; Schmitt, Jochen; Blunier, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation", "url": "https://www.usap-dc.org/view/dataset/601736"}, {"dataset_uid": "601683", "doi": "10.15784/601683", "keywords": "Antarctica; Methane; West Antarctic Ice Sheet", "people": "Riddell-Young, Benjamin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601683"}], "date_created": "Mon, 01 May 2023 00:00:00 GMT", "description": "This project will develop methods to measure the ratios of carbon-13 to carbon-12, and heavy to light hydrogen in methane in air trapped in ice cores. The ratios of the different forms of carbon and hydrogen are \"fingerprints\" of different sources of this gas in the past--for example wetlands in the tropics versus methane frozen in the sea floor. Once the analysis method is developed, the measurements will be used to examine why methane changed abruptly in the past, both during the last ice age, and during previous warm periods. The data will be used to understand how methane sources like wildfires, methane hydrates, and wetlands respond to climate change. This information is needed to understand future risks of large changes in methane in the atmosphere as Earth warms. \u003cbr/\u003e\u003cbr/\u003eThe project involves two tasks. First, the investigators will build and test a gas extraction system for methane isotopic measurements using continuous flow methods, with the goal of equaling or bettering the precision attained by the few other laboratories that make these measurements. The system will be interfaced with existing mass spectrometers at Oregon State University. The system consists of a vacuum chamber and sequence of traps, purification columns, and furnaces that separate methane from other gases and convert it to carbon dioxide or hydrogen for mass spectrometry. Second, the team will measure the isotopic composition of methane across large changes in concentration associated with two past interglacial periods and during abrupt methane changes of the last ice age. These measurements will be used to understand if the main reason for these concentration changes is climate-driven changes in emissions from wetlands, or whether other sources are involved, for example methane hydrates or wildfires.\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": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; TRACE GASES/TRACE SPECIES; METHANE", "locations": "Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores", "uid": "p0010416", "west": -180.0}, {"awards": "2240780 Cohen, Natalie", "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": "Mon, 13 Mar 2023 00:00:00 GMT", "description": "Mixotrophic microorganisms that are capable of both photosynthetic and heterotrophic forms of metabolism are key contributors to primary productivity and organic carbon remineralization in the Southern Ocean. However, uncertainties in their grazing behavior and physiology prevent an accurate understanding of microbial food web dynamics and biogeochemical cycling in the Antarctic ecosystem. Polar mixotrophs have evolved to withstand extreme seasonality, including variable light, sea ice, temperature, and micronutrient concentrations. In particular, the Southern Ocean appears to be the only region of the world\u2019s ocean where the bioessential trace metals iron (Fe) and manganese (Mn) are low enough to inhibit photosynthetic growth. The molecular physiology of mixotrophs experiencing Fe and Mn growth limitation has not yet been examined, and we lack an understanding of how seasonal changes in the availability of these micronutrients influence mixotrophic growth dynamics. We aim to examine whether grazing affords mixotrophs an ecological advantage in the Fe and Mn-deficient Southern Ocean, and to characterize the shifts in metabolic processes that occur during transitions in micronutrient conditions. Culture studies will directly measure growth responses, grazing behavior, and changes in elemental stoichiometry in response to Fe and Mn limitation. Transcriptomic analyses will reveal the metabolic underpinnings of trophic behavior and micronutrient stress responses, with implications for key biogeochemical processes such as carbon fixation, remineralization, and nutrient cycling. ", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "PLANKTON; Georgia; PHYTOPLANKTON", "locations": "Georgia", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cohen, Natalie; Millette, Nicole", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA: Collaborative Research: Mixotrophic Grazing as a Strategy to meet Nutritional Requirements in the Iron and Manganese Deficient Southern Ocean", "uid": "p0010411", "west": -180.0}, {"awards": "2149070 Hawco, Nicholas", "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": "Mon, 13 Mar 2023 00:00:00 GMT", "description": "This proposal represents collaborative research to explore manganese (Mn) limitation in Antarctic diatoms by two early career investigators. Diatoms are central players in the Southern Ocean carbon cycle, where the micronutrient chemistry is fundamentally different from other oceans. The Southern Ocean is characterized by widespread low Mn, coupled with high zinc (Zn). High Zn levels are potentially toxic to diatoms as Zn can competitively inhibit Mn uptake and metabolism, compromising the ability of building critical cellular components, thus impacting the biological pump. Using culture experiments with a matrix of micronutrient treatments (Mn, Zn, Fe) and irradiances, and using physiological and transcriptomic approaches, along with biochemical principles, the Principal Investigators will address the central hypothesis (that diatoms from the Southern Ocean possess unique physiological mechanisms to adapt to low Mn/high Zn) by quantifying rates of uptake and transporter binding constants. The transcriptomics approach will help to identify candidate genes that may provide Antarctic diatoms physiological mechanisms in low Mn/high Zn environment. The project does not require fieldwork but instead would make use of culture experiments with 4 diatom species (3 Antarctic, and 1 temperate). The proposed approach will also enable the goal of developing biomarker(s) for assessing Mn stress or Zn toxicity and results from the physiological experiments will help parameterize models of micronutrient limitation in the Southern Ocean.\r\n\r\nThis 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": "Southern Ocean; BIOGEOCHEMICAL CYCLES; TRACE ELEMENTS; DIATOMS; Iron; Phytoplankton", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hawco, Nicholas; Cohen, Natalie", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA: Collaborative Research: Adaptations of Southern Ocean Diatoms to Manganese Scarcity: Can Physiological Ingenuity Overcome Unfavorable Chemistry?", "uid": "p0010412", "west": -180.0}, {"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": "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"}, {"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/"}], "date_created": "Fri, 03 Mar 2023 00:00:00 GMT", "description": "The Antarctic Circumpolar Current (ACC) is the largest current on the planet, flowing west to east around Antarctica, forming a barrier that separates warmer waters to the north from colder waters to the south. Ocean eddies (like atmospheric storms) break through the ACC barrier, transferring heat across the ACC towards Antarctica. When warmer ocean waters intrude onto the Antarctic continental shelves, they contribute to glacial melt and ice shelf retreat. Over the past several decades, the Southern Ocean has warmed and winds have increased due to climate change. Somewhat surprisingly the ACC, though pushed by faster winds, has not accelerated; a faster current would present a stronger barrier to heat transfer. Instead, ocean eddies have increased. These eddies are concentrated at 6-7 \"hot spots\". Drake Passage is one of these hot spots. As the narrowest land gap on the entire circumpolar path of the ACC, Drake Passsage is an ideal monitoring spot. However, it is also one of the windiest and roughest stretches of water on the globe. The only ship that crosses Drake Passage year-round is the USAP supply vessel for Palmer Station, making it a unique platform to monitor the currents and temperature with a minimum of personnel and resources. The Drake Passage time series of upper ocean currents and temperature is now in its 24th year. The upper ocean temperature measurements have found significant warming in Drake Passage. The upper ocean current measurements have confirmed that the ACC has remained steady on average but have also revealed a complicated filamented current structure. Combining temperature and current measurements has provided a better understanding of heat transfer across the ACC by eddies. The time series has also provided valuable ground-truth for satellite measurements and for numerical model predictions looking at the entire ACC. Our studies are focused on examining low-frequency variability - seasonal, interannual, and decadal - in order to provide baselines from which to evaluate and interpret physical and biogeochemical changes occurring in the Southern Ocean. \r\n", "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": "1543457 Munro, David; 1543511 Stephens, Britton", "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": "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": "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": "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": "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"}, {"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": "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"}], "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 flux of carbon dioxide between the ocean and atmosphere in this region is 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. More specifically, this project is a continuation of the collection of underway upper ocean measurements of the surface partial pressure of carbon dioxide during crossings of the Drake Passage by the Antarctic Research and Supply Vessel Laurence M. Gould. This project also includes collection and analysis of discrete samples relevant to ocean carbon cycle studies including macronutrient concentrations, total carbon dioxide concentrations, and the carbon isotopic composition of total carbon dioxide. 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 Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "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": null, "bounds_geometry": null, "dataset_titles": "Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation", "datasets": [{"dataset_uid": "601660", "doi": "10.15784/601660", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemical data from sediment core at Inexpressible Island in Ross Sea Region during the 2015-2016 Antarctic field investigation", "url": "http://www.usap-dc.org/view/dataset/601660"}], "date_created": "Mon, 30 Jan 2023 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Sediment Core Data", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Liu, Xiaodong", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "2135186 Baumberger, Tamara; 2135185 Resing, Joseph; 2135184 Arrigo, Kevin", "bounds_geometry": "POLYGON((155 -61,156.5 -61,158 -61,159.5 -61,161 -61,162.5 -61,164 -61,165.5 -61,167 -61,168.5 -61,170 -61,170 -61.2,170 -61.4,170 -61.6,170 -61.8,170 -62,170 -62.2,170 -62.4,170 -62.6,170 -62.8,170 -63,168.5 -63,167 -63,165.5 -63,164 -63,162.5 -63,161 -63,159.5 -63,158 -63,156.5 -63,155 -63,155 -62.8,155 -62.6,155 -62.4,155 -62.2,155 -62,155 -61.8,155 -61.6,155 -61.4,155 -61.2,155 -61))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 30 Sep 2022 00:00:00 GMT", "description": "Part 1.\r\nPhytoplankton blooms throughout the world support critical marine ecosystems and help remove harmful CO2 from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either the continental margin or sea-ice. However, recent work demonstrates that hydrothermal vents may be an additional iron source for phytoplankton blooms. This enhancement of phytoplankton productivity by different iron sources supports rich marine ecosystems and leads to the sequestration of C in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton blooms along the southern boundary of the Antarctic Circumpolar Current just north of the Ross Sea. It will also lead towards a better understanding of the overall impact of hydrothermal activity on the C cycle in the Southern Ocean, which appears to trigger local hotspots of enhanced biological activity which are a potential as a sink for atmospheric CO2. This project will encourage the participation of underrepresented groups in ocean sciences, as well as providing educational opportunities for high school and undergraduate students, through three different programs. Stanford University\u2019s Summer Undergraduate Research in Geoscience and Engineering (SURGE) program provides undergraduates from different US universities and diverse cultural backgrounds the opportunity to spend a summer doing a research project at Stanford. The Stanford Earth Summer Undergraduate Research Program (SESUR) is for Stanford undergraduates who want to learn more about environmental science by performing original research. Finally, Stanford\u2019s School of Earth, Energy, and Environmental Sciences High School Internship Program enables young scientists to serve as mentors, prepares high school students for college, and serves to strengthen the partnership between Stanford and local schools. Students present their results at the Fall AGU meeting as part of the AGU Bright STaRS program. This project will form the basis of at least two Ph.D. dissertations. The Stanford student will participate in Stanford\u2019s Woods Institute Rising Environmental Leaders Program (RELP), a year-round program that helps graduate students hone their leadership and communication skills to maximize the impact of their research. The graduate student will also participate in Stanford\u2019s Grant Writing Academy where they will receive training in developing and articulating research strategies to tackle important scientific questions. \r\n\r\nPart 2.\r\nThis interdisciplinary program combines satellite and ship-based measurements of a large poorly understood phytoplankton bloom (the AAR bloom) in the northwestern Ross Sea sector of the Southern Ocean with a detailed modeling study of the physical processes linking deep dissolved iron (DFe) reservoirs to the surface phytoplankton bloom. Prior to the cruise, we will implement a numerical model (CROCO) for our study region so that we can better understand the circulation, plumes, turbulence, fronts, and eddy field around the AAR bloom and how they transport and mix hydrothermally produced DFe vertically. Post cruise, observations of the vertical distribution of 3He (combined with DMn and DFe), will be used as initial conditions for a passive tracer in the model, and tracer dispersal will be assessed to better quantify the role of the various turbulent processes in upwelling DFe-rich waters to the upper ocean. The satellite-based component of the program will characterize the broader sampling region before, during, and after our cruise. During the cruise, our automated software system at Stanford University will download and process images of sea ice concentration, Chl a concentration, sea surface temperature (SST), and SSH and send them electronically to the ship. Operationally, our goal is to use all available satellite data and preliminary model results to target shipboard sampling both geographically and temporally to optimize sampling of the AAR bloom. We will use available BGC-Argo float data to help characterize the AAR bloom. In collaboration with SOCCOM, we will deploy additional BGC-Argo floats (if available) during our transit through the study area to allow us to better characterize the bloom. The centerpiece of our program will be a 40-day process study cruise in austral summer. The cruise will consist of an initial \u201cradiator\u201d pattern of hydrographic surveys/sections along the AAR followed by CTDs to selected submarine volcanoes. When/if eddies are identified, they will be sampled either during or after the initial surveys. The radiator pattern, or parts thereof, will be repeated 2-3 times. Hydrographic survey stations will include vertical profiles of temperature, salinity, oxygen, oxidation-reduction potential, light scatter, and PAR (400-700 nm). Samples will be collected for trace metals, ligands, 3He, and total suspended matter. Where intense hydrothermal activity is identified, samples for pH and total CO2 will also be collected to characterize the hydrothermal system. Water samples will be collected for characterization of macronutrients, and phytoplankton physiology, abundance, species composition, and size. During transits, we will continuously measure atmospheric conditions, current speed and direction, and surface SST, salinity, pCO2, and fluorescence from the ship\u2019s systems to provide detailed maps of these parameters. The ship will be used as a platform for conducting phytoplankton DFe bioassay experiments at key stations throughout the study region both inside and outside the bloom. We will also perform detailed comparisons of algal taxonomic composition, physiology, and size structure inside and outside the bloom to determine the potential importance of each community on local biogeochemistry.", "east": 170.0, "geometry": "POINT(162.5 -62)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; Antarctica; TRACE ELEMENTS; Hydrothermal Vent; Phytoplankton; Primary Production", "locations": "Antarctica", "north": -61.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph", "platforms": null, "repositories": null, "science_programs": null, "south": -63.0, "title": "Collaborative Research: Understanding the Massive Phytoplankton Blooms over the Australian-Antarctic Ridge", "uid": "p0010381", "west": 155.0}, {"awards": "2123491 John, Seth; 2123354 Conway, Timothy; 2123333 Fitzsimmons, Jessica", "bounds_geometry": "POLYGON((-135 -66,-131.5 -66,-128 -66,-124.5 -66,-121 -66,-117.5 -66,-114 -66,-110.5 -66,-107 -66,-103.5 -66,-100 -66,-100 -67,-100 -68,-100 -69,-100 -70,-100 -71,-100 -72,-100 -73,-100 -74,-100 -75,-100 -76,-103.5 -76,-107 -76,-110.5 -76,-114 -76,-117.5 -76,-121 -76,-124.5 -76,-128 -76,-131.5 -76,-135 -76,-135 -75,-135 -74,-135 -73,-135 -72,-135 -71,-135 -70,-135 -69,-135 -68,-135 -67,-135 -66))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 08 Sep 2022 00:00:00 GMT", "description": "The goal of the international GEOTRACES program is to understand the distributions of trace chemical elements and their isotopes (TEIs) in the oceans. Many trace metals such as iron are essential for life and thus considered nutrients for phytoplankton growth, with trace metal cycling being especially important for influencing carbon cycling in the iron-limited Southern Ocean, where episodic supply of iron from a range of different external sources is important. The primary goal of this project is to measure the dissolved concentrations, size partitioning, and dissolved isotope signature of Fe on a transect of water-column stations throughout the Amundsen Sea and surrounding region of the Antarctic Margin, as part of the GP17-ANT Expedition. The secondary goal of this project is to analyze the concentrations and size partitioning of the trace metals manganese, zinc, copper, cadmium, nickel, and lead in all water-column samples, measure the isotope ratios of zinc, cadmium, nickel, and copper in a subset of water column samples, and measure the Fe isotopic signature of aerosols, porewaters, and particles. Observations from this project will be incorporated into regional and global biogeochemistry models to assess TEI cycling within the Amundsen Sea and implications for the wider Southern Ocean. This project spans three institutions, four graduate students, undergraduate students, and will provide ultrafiltered samples and data to other PIs as service.\r\n\r\nThe US GEOTRACES GP17 ANT expedition, planned for austral summer 2023/2024 aims to determine the distribution and cycling of trace elements and their isotopes in the Amundsen Sea Sector (100-135\u00b0W) of the Antarctic Margin. The cruise will follow the Amundsen Sea \u2018conveyor belt\u2019 by sampling waters coming from the Antarctic Circumpolar Current onto the continental shelf, including near the Dotson and Pine Island ice shelves, the productive Amundsen Sea Polynya (ASP), and outflowing waters. Episodic addition of dissolved Fe and other TEIs from dust, ice-shelves, melting ice, and sediments drive seasonal primary productivity and carbon export over the Antarctic shelf and offshore into Southern Ocean. Seasonal coastal polynyas such as the highly productive ASP thus act as key levers on global carbon cycling. However, field observations of TEIs in such regions remain scarce, and biogeochemical cycling processes are poorly captured in models of ocean biogeochemistry. The investigators will use their combined analytical toolbox, in collaboration with the diagnostic chemical tracers and regional models of other funded groups to address four main objectives: 1) What is the relative importance of different sources in supplying Fe and other TEIs to the ASP? 2) What is the physiochemical speciation of this Fe, and its potential for transport? 3) How do biological uptake, scavenging and regeneration in the ASP influence TEI distributions, stoichiometry, and nutrient limitation? 4) What is the flux and signature of TEIs transported offshore to the ACC and Southern Ocean?", "east": -100.0, "geometry": "POINT(-117.5 -71)", "instruments": null, "is_usap_dc": true, "keywords": "R/V NBP; Amundsen Sea; TRACE ELEMENTS; BIOGEOCHEMICAL CYCLES", "locations": "Amundsen Sea", "north": -66.0, "nsf_funding_programs": "Chemical Oceanography; Chemical Oceanography; Chemical Oceanography", "paleo_time": null, "persons": "Conway, Timothy; Fitzsimmons, Jessica; John, Seth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repositories": null, "science_programs": null, "south": -76.0, "title": "Collaborative Research: US GEOTRACES GP17-ANT: Dissolved concentrations, isotopes, and colloids of the bioactive trace metals", "uid": "p0010374", "west": -135.0}, {"awards": "1937595 Briggs, Brandon; 1937546 Morgan-Kiss, Rachael", "bounds_geometry": "POLYGON((162 -77.616667,162.1 -77.616667,162.2 -77.616667,162.3 -77.616667,162.4 -77.616667,162.5 -77.616667,162.6 -77.616667,162.7 -77.616667,162.8 -77.616667,162.9 -77.616667,163 -77.616667,163 -77.6283336,163 -77.6400002,163 -77.6516668,163 -77.6633334,163 -77.67500000000001,163 -77.68666660000001,163 -77.69833320000001,163 -77.7099998,163 -77.7216664,163 -77.733333,162.9 -77.733333,162.8 -77.733333,162.7 -77.733333,162.6 -77.733333,162.5 -77.733333,162.4 -77.733333,162.3 -77.733333,162.2 -77.733333,162.1 -77.733333,162 -77.733333,162 -77.7216664,162 -77.7099998,162 -77.69833320000001,162 -77.68666660000001,162 -77.67500000000001,162 -77.6633334,162 -77.6516668,162 -77.6400002,162 -77.6283336,162 -77.616667))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 27 Jul 2022 00:00:00 GMT", "description": " Microbial communities are of more than just a scientific curiosity. Microbes represent the single largest source of evolutionary and biochemical diversity on the planet. They are the major agents for cycling carbon, nitrogen, phosphorus, and other elements through the ecosystem. Despite their importance in ecosystem function, microbes are still generally overlooked in food web models and nutrient cycles. Moreover, microbes do not live in isolation: their growth and metabolism are influenced by complex interactions with other microorganisms. This project will focus on the ecology, activity and roles of microbial communities in Antarctic Lake ecosystems. The team will characterize the genetic underpinnings of microbial interactions and the influence of environmental gradients (e.g. light, nutrients, oxygen, sulfur) and seasons (e.g. summer vs. winter) on microbial networks in Lake Fryxell and Lake Bonney in the Taylor Valley within the McMurdo Dry Valley region. Finally, the project furthers the NSF goals of training new generations of scientists by including undergraduate and graduate students, a postdoctoral researcher and a middle school teacher in both lab and field research activities. This partnership will involve a number of other outreach training activities, including visits to classrooms and community events, participation in social media platforms, and webinars. \u003cbr/\u003e\u003cbr/\u003ePart II: Technical description: Ecosystem function in the extreme Antarctic Dry Valleys ecosystem is dependent on complex biogeochemical interactions between physiochemical environmental factors (e.g. light, nutrients, oxygen, sulfur), time of year (e.g. summer vs. winter) and microbes. Microbial network complexity can vary in relation to specific abiotic factors, which has important implications on the fragility and resilience of ecosystems under threat of environmental change. This project will evaluate the influence of biogeochemical factors on microbial interactions and network complexity in two Antarctic ice-covered lakes. The study will be structured by three main objectives: 1) infer positive and negative interactions from rich spatial and temporal datasets and investigate the influence of biogeochemical gradients on microbial network complexity using a variety of molecular approaches; 2) directly observe interactions among microbial eukaryotes and their partners using flow cytometry, single-cell sorting and microscopy; and 3) develop metabolic models of specific interactions using metagenomics. Outcomes from amplicon sequencing, meta-omics, and single-cell genomic approaches will be integrated to map specific microbial network complexity and define the role of interactions and metabolic activity onto trends in limnological biogeochemistry in different seasons. These studies will be essential to determine the relationship between network complexity and future climate conditions. Undergraduate researchers will be recruited from both an REU program with a track record of attracting underrepresented minorities and two minority-serving institutions. To further increase polar literacy training and educational impacts, the field team will include a teacher as part of a collaboration with the successful NSF-funded PolarTREC program and participation in activities designed for public outreach.\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": 163.0, "geometry": "POINT(162.5 -77.67500000000001)", "instruments": null, "is_usap_dc": true, "keywords": "MICROALGAE; AQUATIC ECOSYSTEMS; Antarctica; LAKE/POND; BACTERIA/ARCHAEA; COMMUNITY DYNAMICS", "locations": "Antarctica", "north": -77.616667, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Morgan-Kiss, Rachael; Briggs, Brandon", "platforms": null, "repositories": null, "science_programs": null, "south": -77.733333, "title": "ANT LIA: Collaborative Research: Genetic Underpinnings of Microbial Interactions in Chemically Stratified Antarctic Lakes", "uid": "p0010355", "west": 162.0}, {"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?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.\u003cbr/\u003e\u003cbr/\u003e 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.\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": -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": "2055455 Duhaime, Melissa", "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, 03 Jun 2022 00:00:00 GMT", "description": "Part 1: Non-technical description:\r\nIt is well known that the Southern Ocean plays an important role in global carbon cycling and also receives a disproportionately large influence of climate change. The role of marine viruses on ocean productivity is largely understudied, especially in this global region. This team proposes to use combination of genomics, flow cytometry, and network modeling to test the hypothesis that viral biogeography, infection networks, and viral impacts on microbial metabolism can explain variations in net community production (NCP) and carbon cycling in the Southern Ocean. The project includes the training of a postdoctoral scholar, graduate students and undergraduate students. It also includes the development of a new Polar Sci ReachOut program in partnership with the University of Michigan Museum of Natural History especially targeted to middle-school students and teachers and the general public. The team will also produce a Science for Tomorrow (SFT) program for use in middle schools in metro-Detroit communities and lead a summer Research Experience for Teachers (RET) fellows. \r\n\r\nPart 2: Technical description: \r\nThe study will leverage hundreds of existing samples collected for microbes and viruses from the Antarctic Circumpolar Expedition (ACE). These samples provide the first contiguous survey of viral diversity and microbial communities around Antarctica. Viral networks are being studied in the context of biogeochemical data to model community networks and predict net community production (NCP), which will provide a way to evaluate the role of viruses in Southern Ocean carbon cycling. Using cutting edge molecular and flow cytometry approaches, this project addresses the following questions: 1) How/why are Southern Ocean viral populations distributed across environmental gradients? 2a) Do viruses interfere with \"keystone\" metabolic pathways and biogeochemical processes of microbial communities in the Southern Ocean? 2b) Does nutrient availability or other environmental variables drive changes in virus-microbe infection networks in the Southern Ocean? Results will be used to develop and evaluate generative models of NCP predictions that incorporate the importance of viral traits and virus-host interactions.\r\n\r\nThis 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": "Southern Ocean; Amd/Us; AMD; FIELD INVESTIGATION; USA/NSF; AQUATIC SCIENCES; BACTERIA/ARCHAEA; MARINE ECOSYSTEMS; VIRUSES; USAP-DC", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Duhaime, Melissa; Zaman, Luis", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -90.0, "title": "ANT LIA - Viral Ecogenomics of the Southern Ocean: Unifying Omics and Ecological Networks to Advance our Understanding of Antarctic Microbial Ecosystem Function", "uid": "p0010333", "west": -180.0}, {"awards": "1932876 Ball, Becky", "bounds_geometry": "POLYGON((-59.666116 -62.15,-59.5128377 -62.15,-59.3595594 -62.15,-59.2062811 -62.15,-59.0530028 -62.15,-58.8997245 -62.15,-58.7464462 -62.15,-58.5931679 -62.15,-58.4398896 -62.15,-58.2866113 -62.15,-58.133333 -62.15,-58.133333 -62.1731502,-58.133333 -62.1963004,-58.133333 -62.2194506,-58.133333 -62.2426008,-58.133333 -62.265751,-58.133333 -62.2889012,-58.133333 -62.3120514,-58.133333 -62.3352016,-58.133333 -62.3583518,-58.133333 -62.381502,-58.2866113 -62.381502,-58.4398896 -62.381502,-58.5931679 -62.381502,-58.7464462 -62.381502,-58.8997245 -62.381502,-59.0530028 -62.381502,-59.2062811 -62.381502,-59.3595594 -62.381502,-59.5128377 -62.381502,-59.666116 -62.381502,-59.666116 -62.3583518,-59.666116 -62.3352016,-59.666116 -62.3120514,-59.666116 -62.2889012,-59.666116 -62.265751,-59.666116 -62.2426008,-59.666116 -62.2194506,-59.666116 -62.1963004,-59.666116 -62.1731502,-59.666116 -62.15))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 14 Apr 2022 00:00:00 GMT", "description": "Part I: Non-technical summary\u003cbr/\u003eThe Antarctic Peninsula warmed very rapidly in the late part of the 20th century, much faster than the global average, and this warming is predicted to resume and continue over the rest of the 21st century. One consequence of this rapid warming is the melting and subsequent retreat of glaciers, leading to an increase in newly-exposed land on the Peninsula that was previously covered with ice. Once new terrain is exposed, the process of ecological succession begins, with the arrival of early-colonizing plants, such as moss and lichens, and soil organisms - a process commonly referred to as the \u201cgreening\u201d of Antarctica. Early stages of succession will be an increasingly common feature on the Antarctic Peninsula, but the mechanisms by which they occur on the Antarctic continent is not well understood. Once the plants have established on the newly-exposed soil, they can change many important properties, such as water dynamics, nutrient recycling, soil development, and habitat for microscopic organisms, which will ultimately determine the structure and functioning of the future ecosystem as it develops. These relationships between vegetation, soil, and the associated microorganisms, referred to as \u201cplant-soil\u201d interactions, are something we know virtually nothing about. This project will be the first to make a comprehensive study of how the type of colonizing plant, and the expansion of those plants from climate change, will influence terrestrial ecosystems in Antarctica. Understanding these processes is critical to understanding how the greening Antarctica is occurring and how soil communities and processes are influenced by these expanding plant communities. Through this work the research team, will also be intensively training undergraduate and graduate students, including training of students from underrepresented groups and collaborative training of students from Chile and the US. Additionally, the research groups will continue their focus on scientific outreach with K-12 schools and the general public to expand awareness of the effects of climate change in Antarctica.\u003cbr/\u003e\u003cbr/\u003ePart II: Technical summary\u003cbr/\u003eIn this study, the researchers will use surveys across succession sites along the Antarctic Peninsula and Scotia Arc as well as a manipulative field experiment at glacier succession sites to test how species-specific plant functional traits impact soil properties and associated microbial and invertebrate communities in a greening Antarctica. In doing so, they will pursue three integrated aims to understand how Antarctic plant functional traits alter their soil environment and soil communities during succession after glacial retreat. AIM 1) Characterize six fundamental plant functional traits (thermal conductivity, water holding capacity, albedo, decomposability, tissue nutrient content, and secondary chemistry) among diverse Antarctica flora; AIM 2) Measure the relative effects of fundamental plant functional traits on soil physical properties and soil biogeochemistry across glacial succession gradients in Antarctica; and AIM 3) Measure the relative effects of fundamental plant functional traits on soil microbial and invertebrate communities across glacial succession gradients in Antarctica. They will explore how early-colonizing plants, especially mosses and lichens, alter soil physical, biogeochemical, and biological components, potentially impacting later patterns of succession. The researhcers will use intensive surveys of plant-soil interactions across succession sites and a manipulative transplant experiment in the South Shetland Islands, Antarctica to address their aims. The investigators will collect data on plant functional traits and their effects on soil physical properties, biogeochemistry, biotic abundance, and microbial metagenomics. The data collected will be the first comprehensive measures of the relative importance of plant functional types during glacial retreat and vegetative expansion from climate change in Antarctica, aiding our understanding of how plant functional group diversity and abundance are changing in a greening Antarctica.\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": -58.133333, "geometry": "POINT(-58.8997245 -62.265751)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; FIELD SURVEYS; ECOLOGICAL DYNAMICS; USA/NSF; SOIL CHEMISTRY; 25 De Mayo/King George Island; Antarctic Peninsula; PLANTS; Amd/Us; FUNGI; ANIMALS/INVERTEBRATES; USAP-DC; TERRESTRIAL ECOSYSTEMS; BACTERIA/ARCHAEA", "locations": "25 De Mayo/King George Island; Antarctic Peninsula", "north": -62.15, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ball, Becky", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -62.381502, "title": "Collaborative Research: Exploring the Functional Role of Antarctic Plants during Terrestrial Succession", "uid": "p0010315", "west": -59.666116}, {"awards": "2149500 Chambers, Don", "bounds_geometry": "POLYGON((-180 -30,-144 -30,-108 -30,-72 -30,-36 -30,0 -30,36 -30,72 -30,108 -30,144 -30,180 -30,180 -36,180 -42,180 -48,180 -54,180 -60,180 -66,180 -72,180 -78,180 -84,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84,-180 -78,-180 -72,-180 -66,-180 -60,-180 -54,-180 -48,-180 -42,-180 -36,-180 -30))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 14 Mar 2022 00:00:00 GMT", "description": "The Southern Ocean accounts for ~40% of the total ocean uptake of anthropogenic CO2 despite covering only 20% of the global ocean surface, and is particularly rich in long-lived eddies. These eddies, or large ocean whirlpools which can be observed from space, can alter air-sea fluxes of CO2 in ways that are not yet fully understood. New observations from autonomous platforms measuring ocean carbon content suggest that there is significant heterogeneity in ocean carbon fluxes which can be linked to these dynamic eddy features. Due to computational and time limitations, ocean eddies are not explicitly represented in most climate models, limiting our ability to understand the role eddies play in the ocean carbon cycle. This work will explore the impact of eddies on ocean carbon content and air-sea CO2 fluxes in the Southern Ocean using both model- and observation-based strategies and the findings will improve our understanding of the ocean\u2019s role in the carbon cycle and in global climate. While this work will primarily be focused on the Southern Ocean, the results will be globally applicable. The researchers will also broaden interest in physical and chemical oceanography among middle school-age girls in the University of South Florida\u2019s Oceanography Camp for Girls by augmenting existing lessons with computational methods in oceanography. \r\n\r\nThis project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a \u201cModel STEM Program for Women and Girls\u201d focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; Southern Ocean; PH; BIOGEOCHEMICAL CYCLES; AMD; OCEAN CHEMISTRY; OCEAN MIXED LAYER; USA/NSF; NITROGEN; OCEAN CURRENTS; SALINITY/DENSITY; USAP-DC; OCEAN TEMPERATURE; MODELS; CHLOROPHYLL; DISSOLVED GASES; NUTRIENTS", "locations": "Southern Ocean", "north": -30.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Williams, Nancy; Chambers, Don; Tamsitt, Veronica", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Diagnosing the Role of Ocean Eddies in Carbon Cycling from a High-resolution Data Assimilating Ocean Biogeochemical Model", "uid": "p0010309", "west": -180.0}, {"awards": "2149501 Mazloff, 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": null, "datasets": null, "date_created": "Fri, 04 Mar 2022 00:00:00 GMT", "description": "This project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a \u201cModel STEM Program for Women and Girls\u201d focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; AMD; USA/NSF; USAP-DC; MODELS; BIOGEOCHEMICAL CYCLES; Amd/Us", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Mazloff, Matthew", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Diagnosing the role of ocean eddies in carbon cycling from a high- resolution data assimilating ocean biogeochemical model", "uid": "p0010304", "west": -180.0}, {"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": "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"}, {"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/"}], "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. \r\n\r\nThe 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": "1847067 Levy, Joseph", "bounds_geometry": "POLYGON((161 -76,161.35 -76,161.7 -76,162.05 -76,162.4 -76,162.75 -76,163.1 -76,163.45 -76,163.8 -76,164.15 -76,164.5 -76,164.5 -76.2,164.5 -76.4,164.5 -76.6,164.5 -76.8,164.5 -77,164.5 -77.2,164.5 -77.4,164.5 -77.6,164.5 -77.8,164.5 -78,164.15 -78,163.8 -78,163.45 -78,163.1 -78,162.75 -78,162.4 -78,162.05 -78,161.7 -78,161.35 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76))", "dataset_titles": "Biogeochemical measurements of water tracks and adjacent dry soils from the McMurdo Dry Valleys; Surface Water Geochemistry from the McMurdo Dry Valleys", "datasets": [{"dataset_uid": "601684", "doi": "10.15784/601684", "keywords": "Antarctica; Cation Exchange; Chemistry:soil; Chemistry:Soil; Dry Valleys; Organic Matter; Salt; Soil", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemical measurements of water tracks and adjacent dry soils from the McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601684"}, {"dataset_uid": "601703", "doi": "10.15784/601703", "keywords": "Antarctica; Dry Valleys", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Surface Water Geochemistry from the McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601703"}], "date_created": "Fri, 24 Dec 2021 00:00:00 GMT", "description": "Antarctic groundwater drives the regional carbon cycle, accelerates permafrost thaw, and shapes Antarctic climate response. However, groundwater extent, movement, and processes on a continent virtually locked in ice are poorly understood. The proposed work investigates the interplay between groundwater, sediment, and ice in Antarctica\u2019s cold desert landscapes to determine when, where, and why Antarctic groundwater is flowing, and how quickly it will switch Antarctic frozen deserts from dry and stable to wet and disintegrating. Little is known about the extent, chemistry, and duration of groundwater in Antarctic seasonal wetlands. Mapping the changing extent of Antarctic wetlands requires the ability to measure soil moisture rapidly and repeatedly and over large areas. Changing groundwater extent will be captured through an unmanned aerial vehicle (UAV)-based mapping approach. The project integrates a diverse range of sensors with new UAV technologies to provide a higher-resolution and more frequent assessment of Antarctic groundwater extent and composition than can be accomplished using satellite observations alone. To complement the research objectives, the PI will develop a new UAV summer field school, the Geosciences UAV Academy, focused on training undergraduate-level UAV pilots in conducting novel Earth science research using cutting edge imaging tools. The integration of research and technology will prepare students for careers in burgeoning UAV-related industries and research. The project will deliver new UAV tools and workflows for soil moisture mapping relevant to arid regions common not just to Antarctica but to temperate desert and dryland systems and will train student research pilots to tackle next generation airborne challenges. \r\n\r\nWater tracks are the basic hydrological unit that currently feeds the rapidly-changing polar and permafrost wetlands in the Antarctic McMurdo Dry Valleys (MDV). Despite the importance of water tracks in the MDV hydrologic cycle and their influence on biogeochemistry, little is known about how these water tracks control the unique brine processes operating in Antarctic ice-free areas. Both groundwater availability and geochemistry shape Antarctic microbial communities, connecting soil geology and hydrology to carbon cycling and ecosystem functioning. The objectives of this CAREER proposal are to 1) map water tracks to determine the spatial distribution and seasonal magnitude of groundwater impacts on the MDV near-surface environment to determine how water tracks drive irreversible permafrost thaw, how water tracks enhance chemical weathering and biogeochemical cycling, and how water tracks integrate and accelerate climate feedbacks between terrestrial Antarctic soils and the Southern Ocean; 2) establish a UAV academy training earth sciences students to answer geoscience questions using drone-based platforms and remote sensing techniques; and 3) provide a formative step in the development of the PI as a teacher-scholar. UAV-borne hyperspectral imaging complemented with field soil sampling will determine the aerial extent and timing of inundation, water level, and water budget of representative water tracks in the MDV. Soil moisture will be measured via near-infrared reflectance spectroscopy while bulk chemistry of soils and groundwater will be analyzed via ion chromatography and soil x-ray fluorescence. Sedimentological and hydrological properties (suction/matric potential, hydraulic conductivity, etc.) will be determined via analysis of intact core samples. These data will be used to test competing hypotheses regarding the origin of water track solutions and water movement through seasonal wetlands. The will provide a regional understanding of Antarctic groundwater sources, groundwater flux, and the influence of regional hydrogeology on solute export to the Southern Ocean and on soil/atmosphere linkages in earth\u2019s carbon budget. The UAV school will 1) provide comprehensive instruction at the undergraduate level in both how and why UAVs can be used in geoscience research and learning; and 2) provide a long-term piece of educational infrastructure in the form of an ultimately self-sustaining summer program for undergraduate UAV education. \r\n", "east": 164.5, "geometry": "POINT(162.75 -77)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Amd/Us; USA/NSF; AMD; USAP-DC; FROZEN GROUND; Taylor Valley", "locations": "Taylor Valley", "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Levy, Joseph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Linking Antarctic Cold Desert Groundwater to Thermokarst \u0026 Chemical Weathering in Partnership with the Geoscience UAV Academy", "uid": "p0010286", "west": 161.0}, {"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": "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. It is also the largest potential contributor to future sea level rise and a major uncertainty in climate projections. Climate change may trigger instabilities, which may lead to fast and irreversible collapse of parts of the ice sheet. However, very 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. This project investigates Antarctic ice-ocean interactions of the last 20,000 years. A novel numerical climate model will be constructed 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. Paleoclimate data will be synthesized and compared with simulations of the model. The model-data comparison will address 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.\r\n\r\nThis project will test suggestions 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.", "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": "1947562 van Gestel, Natasja; 1643871 van Gestel, Natasja", "bounds_geometry": "POLYGON((-65 -64.5,-64.8 -64.5,-64.6 -64.5,-64.4 -64.5,-64.2 -64.5,-64 -64.5,-63.8 -64.5,-63.6 -64.5,-63.4 -64.5,-63.2 -64.5,-63 -64.5,-63 -64.55,-63 -64.6,-63 -64.65,-63 -64.7,-63 -64.75,-63 -64.8,-63 -64.85,-63 -64.9,-63 -64.95,-63 -65,-63.2 -65,-63.4 -65,-63.6 -65,-63.8 -65,-64 -65,-64.2 -65,-64.4 -65,-64.6 -65,-64.8 -65,-65 -65,-65 -64.95,-65 -64.9,-65 -64.85,-65 -64.8,-65 -64.75,-65 -64.7,-65 -64.65,-65 -64.6,-65 -64.55,-65 -64.5))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 21 Aug 2021 00:00:00 GMT", "description": "Responses of the carbon balance of terrestrial ecosystems to warming will feed back to the pace of climate change, but the size and direction of this feedback are poorly constrained. Least known are the effects of warming on carbon losses from soil, and clarifying the major microbial controls is an important research frontier. This study uses a series of experiments and observations to investigate microbial, including autotrophic taxa, and plant controls of net ecosystem productivity in response to warming in intact ecosystems. Field warming is achieved using open-top chambers paired with control plots, arrayed along a productivity gradient. Along this gradient incoming and outgoing carbon fluxes will be measured at the ecosystem-level. The goal is to tie warming-induced shifts in net ecosystem carbon balance to warming effects on soil microbes and plants. The field study will be supplemented with lab temperature incubations. Because soil microbes dominate biogeochemical cycles in Antarctica, a major focus of this study is to determine warming responses of bacteria, fungi and archaea. This is achieved using a cutting-edge stable isotope technique, quantitative stable isotope probing (qSIP) developed by the proposing research team, that can identify the taxa that are active and involved in processing new carbon. This technique can identify individual microbial taxa that are actively participating in biogeochemical cycling of nutrients (through combined use of 18O-water and 13C-bicarbonate) and thus can be distinguished from those that are simply present (cold-preserved). The study further assesses photosynthetic uptake of carbon by the vegetation and their sensitivity to warming. Results will advance research in climate change, plant and soil microbial ecology, and ecosystem modeling.", "east": -63.0, "geometry": "POINT(-64 -64.75)", "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; TERRESTRIAL ECOSYSTEMS; USA/NSF; AMD; Amd/Us; USAP-DC; FIELD SURVEYS", "locations": "Palmer Station", "north": -64.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "van Gestel, Natasja", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -65.0, "title": "Antarctica as a Model System for Responses of Terrestrial Carbon Balance to Warming", "uid": "p0010251", "west": -65.0}, {"awards": "1941304 Sherrell, Robert; 1941483 Yager, Patricia; 1941327 Stammerjohn, Sharon; 1941292 St-Laurent, Pierre; 1941308 Fitzsimmons, Jessica", "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": "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": "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": "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": " The Amundsen Sea hosts the most productive polynya in all of Antarctica, with its vibrant green waters visible from space, and an atmospheric CO2 uptake density 10x 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 (WAIS). ARTEMIS aims to characterize the climate-sensitive nature of glacial meltwater-driven micronutrient (iron, Fe) contributions driving ecosystem productivity and CO2 uptake in the coastal Antarctic. We propose to integrate observations and ocean modeling of these processes to enhance predictive capabilities. Currently, basal melt resulting from warm deep waters penetrating ice shelf cavities dominates mass losses of WAIS, contributing to sea level rise. These physical melting processes are being studied by the International Thwaites Glacier Collaboration (ITGC). The impact of melting on the marine ecosystem has also been explored, and we know that productivity is due in part to Fe-rich, glacial meltwater-driven outflow. The biogeochemical composition of the outflow from the glaciers surrounding the Amundsen Sea is largely unstudied, however. Improved knowledge would provide keys to understanding meltwater\u0027s future impact on the ecosystem. An ongoing field program (TARSAN, part of the ITGC) offers the ideal physical oceanographic framework for our biogeochemical effort. We propose here to collaborate with TARSAN-supported UK scientists, providing value added to both team efforts. ARTEMIS will add shipboard measurements (trace metals, carbonate system, nutrients, organic matter, microorganisms) and biogeochemical sensors on autonomous vehicles to gather critical knowledge needed to understand the impact of the melting WAIS on both the coastal ecosystem and the regional carbon (C) cycle. Driving questions include: 1) what are the fluxes and chemical forms of Fe, C, and microorganisms in the ice shelf outflow? 2) what are the relative contributions to the ouflow from deep water, benthic, and glacial melt sources, and how do these inputs combine to affect the bioavailability of Fe? 3) How are Fe and C compounds modified as the outflow advects along the coastal current and mixes into the bloom region? and 4) what will be the effect of increased glacial melting, changes in the coastal icescape, and declining sea ice on theecosystem of the Amundsen Sea? Such questions fall outside the focus of the ITGC, but are of keen interest to Antarctic Organisms and Ecosystems and Antarctic Integrated System Science programs.", "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": "1937748 Sumner, Dawn", "bounds_geometry": "POINT(163.183333 -77.616667)", "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": "Hawes, Ian; Sumner, Dawn; Paul, Ann; Mackey, Tyler; Juarez Rivera, Marisol", "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": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "This project focuses on understanding annual changes in microbial life that grows on the bottom of Lake Fryxell, Antarctica. Because of its polar latitude, photosynthesis can only occur during the summer. During summer, photosynthetic bacteria supply communities with energy and oxygen. However, it is unknown how the microbes behave in the dark winter, when observations are not possible. This project will perform laboratory experiments with a cyanobacterial mat grown from Lake Fryxell samples. Once fieldwork is allowed, we will install environmental monitors and light-blocking shades over small parts of the communities in Lake Fryxell. The shades will extend winter conditions into the spring to allow researchers to characterize the winter behavior of the microbial communities. Researchers will measure changes in the water chemistry due to their activities when they first receive light as the shades are removed. Results are expected to provide insights into how organisms interact with and change their environments. \r\n\r\nThe project extends these scientific results to building a better-prepared, more diverse workforce to perform scientific fieldwork. Fieldwork, including diving, will be performed in part by graduate students under the mentorship of world experts in Antarctic field science. In addition, the project will help students and early career scientists learn field skills by building an online \u201cGuide to Thrive.\u201d This web site will compile field tips ranging from basic gear use to advanced environmental protection techniques. Group leaders ranging from undergraduate teaching assistants to Antarctic expedition leaders will be able to choose appropriate components to build tailored guides for their participants to help them thrive in difficult field conditions. \r\n\r\nThe researchers will measure laboratory-based and field-based seasonal metabolic and biogeochemical changes in benthic mats using differential gene expression and geochemical gradients. They will identify seasonal phenotypic differences and ecosystem effects induced by spring oxygen production. To do so, researchers will install environmental sensors and opaque shades over mats at three depths in the lake. The following spring, they will sample shaded and unshaded mats, remove the shades, track changes in pore water O2, H2S, pH, and redox with microelectrodes, and sample mats for transcriptomic analyses at intervals guided by geochemical changes. Pore water will be sampled for nutrient analyses. Field research will be supplemented with: laboratory experiments to refine field techniques (expanded effort due to COVID field restrictions); gene expression data analysis; and integration of results into a seasonal model of productivity and nitrogen cycling in Lake Fryxell. Results will provide insights into several key priorities for NSF, including how biotic, abiotic and environmental components of the benthic mats interact to affect the regional ecosystem.\r\n", "east": 163.183333, "geometry": "POINT(163.183333 -77.616667)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Amd/Us; AMD; USA/NSF; FIELD SURVEYS; ECOSYSTEM FUNCTIONS; Lake Fryxell; USAP-DC; LAKE/POND", "locations": "Antarctica; Lake Fryxell", "north": -77.616667, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Sumner, Dawn; Mackey, Tyler", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.616667, "title": "Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys", "uid": "p0010219", "west": 163.183333}, {"awards": "1643345 Popp, Brian; 1643466 Hollibaugh, James", "bounds_geometry": "POLYGON((-78.20206667 -64.03195833,-76.785055836 -64.03195833,-75.368045002 -64.03195833,-73.951034168 -64.03195833,-72.534023334 -64.03195833,-71.1170125 -64.03195833,-69.700001666 -64.03195833,-68.282990832 -64.03195833,-66.865979998 -64.03195833,-65.448969164 -64.03195833,-64.03195833 -64.03195833,-64.03195833 -64.554377497,-64.03195833 -65.076796664,-64.03195833 -65.599215831,-64.03195833 -66.121634998,-64.03195833 -66.644054165,-64.03195833 -67.166473332,-64.03195833 -67.688892499,-64.03195833 -68.211311666,-64.03195833 -68.733730833,-64.03195833 -69.25615,-65.448969164 -69.25615,-66.865979998 -69.25615,-68.282990832 -69.25615,-69.700001666 -69.25615,-71.1170125 -69.25615,-72.534023334 -69.25615,-73.951034168 -69.25615,-75.368045002 -69.25615,-76.785055836 -69.25615,-78.20206667 -69.25615,-78.20206667 -68.733730833,-78.20206667 -68.211311666,-78.20206667 -67.688892499,-78.20206667 -67.166473332,-78.20206667 -66.644054165,-78.20206667 -66.121634998,-78.20206667 -65.599215831,-78.20206667 -65.076796664,-78.20206667 -64.554377497,-78.20206667 -64.03195833))", "dataset_titles": "\"Collaborative research: Chemoautotrophy in Antarctic bacterioplankton communities supported by the oxidation of urea-derived nitrogen\"; Expedition data of LMG1801", "datasets": [{"dataset_uid": "200193", "doi": "Not yet assigned", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "\"Collaborative research: Chemoautotrophy in Antarctic bacterioplankton communities supported by the oxidation of urea-derived nitrogen\"", "url": "https://www.bco-dmo.org/project/775717"}, {"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"}], "date_created": "Fri, 18 Dec 2020 00:00:00 GMT", "description": "The project addressed fundamental questions regarding the role of nitrification (the conversion of ammonium to nitrate by a two-step process involving two different guilds of microorganisms: ammonia- and nitrite-oxidizers) in the Antarctic marine ecosystem. Specifically, the project evaluated the contribution of carbon fixation supported by energy derived from the oxidation of nitrogen compounds (chemoautotrophy) to the overall supply of organic carbon to the food web of the Southern Ocean. Additionally, the project aimed to determine the significance of the contribution of other sources of reduced nitrogen, specifically organic nitrogen and urea, to nitrification because these contributions may not be assessed by standard protocols. \n\n\u003cbr\u003e\u003cbr\u003eWe quantified the oxidation rates of 15N supplied as ammonium, urea and nitrite, which allowed us to estimate the contribution of urea-derived N and complete nitrification (ammonia to nitrate, N-3 to N+5) to chemoautotrophy in Antarctic coastal waters. We compared these estimates to direct measurements of the incorporation of dissolved inorganic 14C into organic matter in the dark for an independent estimate of chemoautotrophy. We made measurements on samples taken from the major water masses: surface water (~10 m), winter water (35-174 m), circumpolar deep water (175-1000 m) and slope water (\u003e1000 m); on a cruise surveying the continental shelf and slope west of the Antarctic Peninsula in the austral summer of 2018 (LMG18-01). Samples were also taken to measure the concentrations of nitrite, ammonia, urea and polyamines; for qPCR analysis of the abundance of relevant marker genes; and for studies of processes related to the core questions of the study. The project relied on collaboration with the Palmer LTER for ancillary data (bacterioplankton abundance and production, chlorophyll, physical and additional chemical variables). The synergistic activities of this project along with the LTER activities provides a unique opportunity to assess chemoautotrophy in context of the overall ecosystem\u0027s dynamics, including both primary and secondary production processes.\n\u003cbr\u003e\u003cbr\u003eThis project resulted in the training of a postdoctoral researcher and provide undergraduate students opportunities to gain hand-on experience with research on microbial geochemistry. This project contributed substantially to understanding an important aspect of nitrogen cycling and bacterioplankton production in the study area. Both PIs participate fully in the education and outreach efforts of the Palmer LTER, including making highlights of the findings available for posting to the LTER project web site, posting material to web sites at their respective departments, and incorporating material from the study in lectures and seminars presented at their respective institutions. \n", "east": -64.03195833, "geometry": "POINT(-71.1170125 -66.644054165)", "instruments": null, "is_usap_dc": true, "keywords": "Pal-Lter; NITROGEN; SHIPS; USAP-DC; MARINE ECOSYSTEMS; BACTERIA/ARCHAEA; BIOGEOCHEMICAL CYCLES; Amd/Us; West Antarctic Shelf; USA/NSF; AMD", "locations": "West Antarctic Shelf; Pal-Lter", "north": -64.03195833, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hollibaugh, James T.; Popp, Brian", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "BCO-DMO", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -69.25615, "title": "Collaborative Research: Chemoautotrophy in Antarctic Bacterioplankton Communities Supported by the Oxidation of Urea-derived Nitrogen", "uid": "p0010150", "west": -78.20206667}, {"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": "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"}, {"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"}], "date_created": "Fri, 25 Sep 2020 00:00:00 GMT", "description": "General:\r\nScientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth\u2019s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean that regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. This project was designed 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 the 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 was to 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 was expected to 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. \r\n\r\nTechnical:\r\nThe project added a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that collected sediment cores at locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170\u00b0W. The goal was 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. We proposed to compare the radiocarbon age of foraminifera that inhabited the surface ocean with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms would have been 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 was expected that surface and deep-dwelling foraminifera would 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 outcrop at the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work was 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\u2019s 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 Antarctica. \r\n\r\nUnfortunately, the cores were shipped to the core repository in a horizontal orientation and there was sufficient distortion of the sediment that the radiocarbon ages of benthic foraminifera were uninterpretable. Therefore, we report only the radiocarbon dates for planktonic foraminifera as well as the total counts of elemental relative abundance from X-ray Fluorescence analysis of the cores. In addition, we used the expedition as an opportunity to collect water samples from which dissolved concentrations of long-lived isotope of thorium and protactinium were determined. Results from those analyses showed that lateral transport by isopycnal mixing dominates the supply of Pa to the Southern Ocean. We have also developed a new algorithm to correct for supply of Th by isopycnal mixing and thereby derive estimates of dust flux to the Southern Ocean. \r\n", "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": "NCEI", "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": "1644187 Tulaczyk, Slawek", "bounds_geometry": "POLYGON((161 -76.9,161.75 -76.9,162.5 -76.9,163.25 -76.9,164 -76.9,164.75 -76.9,165.5 -76.9,166.25 -76.9,167 -76.9,167.75 -76.9,168.5 -76.9,168.5 -77.04,168.5 -77.18,168.5 -77.32,168.5 -77.46,168.5 -77.6,168.5 -77.74,168.5 -77.88,168.5 -78.02,168.5 -78.16,168.5 -78.3,167.75 -78.3,167 -78.3,166.25 -78.3,165.5 -78.3,164.75 -78.3,164 -78.3,163.25 -78.3,162.5 -78.3,161.75 -78.3,161 -78.3,161 -78.16,161 -78.02,161 -77.88,161 -77.74,161 -77.6,161 -77.46,161 -77.32,161 -77.18,161 -77.04,161 -76.9))", "dataset_titles": "ANTAEM project airborne EM resistivity data from McMurdo Region", "datasets": [{"dataset_uid": "601373", "doi": "10.15784/601373", "keywords": "Antarctica; Dry Valleys; Hydrology; Ice Shelf; McMurdo; Permafrost", "people": "Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "ANTAEM project airborne EM resistivity data from McMurdo Region", "url": "https://www.usap-dc.org/view/dataset/601373"}], "date_created": "Sun, 13 Sep 2020 00:00:00 GMT", "description": "In Antarctica, millions of years of freezing have led to the development of hundreds of meters of thick permafrost (i.e., frozen ground). Recent research demonstrated that this slow freezing has trapped and concentrated water into local and regional briny aquifers, many times more salty than seawater. Because salt depresses the freezing point of water, these saline brines are able to persist as liquid water at temperatures well below the normal freezing point of freshwater. Such unusual groundwater systems may support microbial life, supply nutrients to coastal ocean and ice-covered lakes, and influence motion of glaciers. These briny aquifers also represent potential terrestrial analogs for deep life habitats on other planets, such as Mars, and provide a testing ground for the search for extraterrestrial water. Whereas much effort has been invested in understanding the physics, chemistry, and biology of surface and near-surface waters in cold polar regions, it has been comparably difficult to investigate deep subsurface aquifers in such settings. Airborne ElectroMagnetics (AEM) subsurface imaging provides an efficient way for mapping salty groundwater. An international collaboration with the University of Aarhus in Denmark will enable knowledge and skill transfer in AEM techniques that will enhance US polar research capabilities and provide US undergraduates and graduate students with unique training experiences. This project will survey over 1000 km2 of ocean and land near McMurdo Station in Antarctica, and will reveal if cold polar deserts hide a subsurface pool of liquid water. This will have significant implications for understanding cold polar glaciers, ice-covered lakes, frozen ground, and polar microbiology as well as for predictions of their response to future change. Improvements in permafrost mapping techniques and understanding of permafrost and of underlying groundwaters will benefit human use of high polar regions in the Antarctic and the Arctic.\u003cbr/\u003e\u003cbr/\u003eThe project will provide the first integrative system-scale overview of subsurface water distribution and hydrological connectivity in a partly ice-free coastal region of Antarctica, the McMurdo Dry Valleys. Liquid water is relatively scarce in this environment but plays an outsized role by influencing, and integrating, biological, biogeochemical, glaciological, and geological processes. Whereas surface hydrology and its role in ecosystem processes has been thoroughly studied over the last several decades, it has been difficult to map out and characterize subsurface water reservoirs and to understand their interactions with regional lakes, glaciers, and coastal waters. The proposed project builds on the \"proof-of-concept\" use of AEM technology in 2011. Improvements in sensor and data processing capabilities will result in about double the depth of penetration of the subsurface during the new data collection when compared to the 2011 proof-of-concept survey, which reached depths of 300-400m. The first field season will focus on collecting deep soundings with a ground-based system in key locations where: (i) independent constraints on subsurface structure exist from past drilling projects, and (ii) the 2011 resistivity dataset indicates the need for deeper penetration and high signal-to-noise ratios achievable only with a ground-based system. The regional airborne survey will take place during the second field season and will yield subsurface electrical resistivity data from across several valleys of different sizes and different ice cover fractions.", "east": 168.5, "geometry": "POINT(164.75 -77.6)", "instruments": null, "is_usap_dc": true, "keywords": "FROZEN GROUND; GLACIERS/ICE SHEETS; HELICOPTER; GROUND WATER; RIVERS/STREAMS; Dry Valleys", "locations": "Dry Valleys", "north": -76.9, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Mikucki, Jill", "platforms": "AIR-BASED PLATFORMS \u003e ROTORCRAFT/HELICOPTER \u003e HELICOPTER", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.3, "title": "Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica", "uid": "p0010129", "west": 161.0}, {"awards": "1543450 Countway, Peter", "bounds_geometry": "POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63))", "dataset_titles": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ; Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Western Antarctic Peninsula plankton raw sequence reads", "datasets": [{"dataset_uid": "601645", "doi": "10.15784/601645", "keywords": "Antarctica; Nitrate; Nitrite; Palmer Station; Phosphate", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ", "url": "https://www.usap-dc.org/view/dataset/601645"}, {"dataset_uid": "601644", "doi": "10.15784/601644", "keywords": "3H-Leu; Antarctica; Bacteria; Biota; DMSP; Heterotrophic Bacterial Production; Palmer Station", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601644"}, {"dataset_uid": "601646", "doi": "10.15784/601646", "keywords": "Antarctica; Carbon; Dissolved Organic Carbon; Nitrogen; Palmer Station; TDN; Total Dissolved Nitrogen", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601646"}, {"dataset_uid": "601648", "doi": "10.15784/601648", "keywords": "Antarctica; Biota; Dimethyl Sulfide; Dimethylsulfoniopropionate; Dimethylsulfoxide; DMSP; DMSP Lyase; Palmer Station", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601648"}, {"dataset_uid": "200337", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Western Antarctic Peninsula plankton raw sequence reads", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA870587?reviewer=bmud2tbbrqbus79i2n2hb83uio"}, {"dataset_uid": "601647", "doi": "10.15784/601647", "keywords": "Antarctica; Palmer Station; Phytoplankton", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601647"}], "date_created": "Sat, 01 Aug 2020 00:00:00 GMT", "description": "The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\\DMS production. The project examined the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project interacted with elementary students in Maine and brought undergraduate students to Bigelow Laboratory. The project also engaged with a science writer and illustrator who joined the team in Palmer Station in 2018. Many posts are available at xxx\r\n\r\nThe project is examining (1) the extent to which the cycling of DMSP in southern ocean waters influenced the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influenced the magnitude and rates of DMSP cycling; we are awaiting results on (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to field experimental additions of DMSP; and, this year (2020-21), we will synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work was accomplished by conducting continuous growth experiments with DMSP-amended natural samples of different microbial communities present in summer (2016-17) and fall (2018) at Palmer Station, WAP. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis in the coming year (2020-21). ", "east": -63.0, "geometry": "POINT(-64.5 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; COMMUNITY DYNAMICS; FIELD INVESTIGATION; AMD; PLANKTON; Amd/Us; BIOGEOCHEMICAL CYCLES; Palmer Station; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Countway, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "GenBank; USAP-DC", "science_programs": null, "south": -66.0, "title": "Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean", "uid": "p0010120", "west": -66.0}, {"awards": "1543537 Priscu, John; 1543347 Rosenheim, Brad; 1543453 Lyons, W. Berry; 1543396 Christner, Brent; 1543405 Leventer, Amy; 1543441 Fricker, Helen", "bounds_geometry": "POLYGON((-163.611 -84.33543,-162.200034 -84.33543,-160.789068 -84.33543,-159.378102 -84.33543,-157.967136 -84.33543,-156.55617 -84.33543,-155.145204 -84.33543,-153.734238 -84.33543,-152.323272 -84.33543,-150.912306 -84.33543,-149.50134 -84.33543,-149.50134 -84.3659157,-149.50134 -84.3964014,-149.50134 -84.4268871,-149.50134 -84.4573728,-149.50134 -84.4878585,-149.50134 -84.5183442,-149.50134 -84.5488299,-149.50134 -84.5793156,-149.50134 -84.6098013,-149.50134 -84.640287,-150.912306 -84.640287,-152.323272 -84.640287,-153.734238 -84.640287,-155.145204 -84.640287,-156.55617 -84.640287,-157.967136 -84.640287,-159.378102 -84.640287,-160.789068 -84.640287,-162.200034 -84.640287,-163.611 -84.640287,-163.611 -84.6098013,-163.611 -84.5793156,-163.611 -84.5488299,-163.611 -84.5183442,-163.611 -84.4878585,-163.611 -84.4573728,-163.611 -84.4268871,-163.611 -84.3964014,-163.611 -84.3659157,-163.611 -84.33543))", "dataset_titles": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset; Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland; CTD data from Mercer Subglacial Lake and access borehole; Discrete bulk sediment properties data from Mercer Subglacial Lake; Isotopic data from Whillans Ice Stream grounding zone, West Antarctica; Mercer Subglacial Lake radiocarbon and stable isotope data ; Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995); Mercer Subglacial Lake (SLM) noble gas and isotopic data; Mercer Subglacial Lake water column viral metagenomic sequencing; Salsa sediment cores; Sediment porewater properties data from Mercer Subglacial Lake; Water column biogeochemical data from Mercer Subglacial Lake", "datasets": [{"dataset_uid": "601661", "doi": "10.15784/601661", "keywords": "Antarctica; Carbon; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; Physical Properties; SALSA; Sediment Core; Sulfur; West Antarctic Ice Sheet", "people": "Skidmore, Mark; Hawkings, Jon; Science Team, SALSA; Michaud, Alexander; Tranter, Martyn; Venturelli, Ryan A; Campbell, Timothy; Dore, John", "repository": "USAP-DC", "science_program": null, "title": "Discrete bulk sediment properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601661"}, {"dataset_uid": "601498", "doi": "10.15784/601498", "keywords": "Antarctica; Mercer Subglacial Lake; Noble Gas", "people": "Gardner, Christopher B.; Lyons, W. Berry", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake (SLM) noble gas and isotopic data", "url": "https://www.usap-dc.org/view/dataset/601498"}, {"dataset_uid": "601663", "doi": "10.15784/601663", "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "people": "Steigmeyer, August; Dore, John; Skidmore, Mark; Hawkings, Jon; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; Science Team, SALSA", "repository": "USAP-DC", "science_program": null, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601663"}, {"dataset_uid": "200215", "doi": "10.7283/C503-KS23", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/C503-KS23"}, {"dataset_uid": "601664", "doi": "10.15784/601664", "keywords": "Antarctica; Gas; Geochemistry; Glacier; Glaciology; Mercer Subglacial Lake; Methane; SALSA; Sediment Core; West Antarctic Ice Sheet", "people": "Michaud, Alexander; Skidmore, Mark; Science Team, SALSA; Steigmeyer, August; Tranter, Martyn; Dore, John", "repository": "USAP-DC", "science_program": null, "title": "Sediment porewater properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601664"}, {"dataset_uid": "200216", "doi": "10.7283/F8NH-CV04", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F8NH-CV04"}, {"dataset_uid": "601672", "doi": "10.15784/601672", "keywords": "Antarctica; Isotope; Mercer Subglacial Lake; Radiocarbon; Subglacial Lake", "people": "Rosenheim, Brad; Venturelli, Ryan", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake radiocarbon and stable isotope data ", "url": "https://www.usap-dc.org/view/dataset/601672"}, {"dataset_uid": "200217", "doi": "10.7283/3JMY-Y504", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/3JMY-Y504"}, {"dataset_uid": "601472", "doi": "10.15784/601472", "keywords": "Antarctica; Bistatic Radar; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS Data; Greenland; Lake Whillans; Radar; Store Glacier; Whillans Ice Stream; WISSARD", "people": "Peters, Sean; Bienert, Nicole; Schroeder, Dustin; Siegfried, Matthew; MacKie, Emma; Dawson, Eliza; Christoffersen, Poul", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland", "url": "https://www.usap-dc.org/view/dataset/601472"}, {"dataset_uid": "601360", "doi": "10.15784/601360", "keywords": "Antarctica; Radiocarbon; Sediment; Whillans Ice Stream", "people": "Venturelli, Ryan A", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Isotopic data from Whillans Ice Stream grounding zone, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601360"}, {"dataset_uid": "200246", "doi": "", "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "Salsa sediment cores", "url": "https://osu-mgr.org"}, {"dataset_uid": "200282", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA790995"}, {"dataset_uid": "200342", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Mercer Subglacial Lake water column viral metagenomic sequencing", "url": "https://www.ncbi.nlm.nih.gov/biosample/32811410"}, {"dataset_uid": "200213", "doi": "10.7283/F7BB-JH05", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F7BB-JH05"}, {"dataset_uid": "200214", "doi": "10.7283/YW8Z-TK03", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/YW8Z-TK03"}, {"dataset_uid": "200212", "doi": "10.7283/PT0Q-JB95", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/PT0Q-JB95"}, {"dataset_uid": "601657", "doi": "10.15784/601657", "keywords": "Antarctica; Conductivity; CTD; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hot Water Drill; Mercer Subglacial Lake; Physical Properties; SALSA; Subglacial Lake; Temperature", "people": "Dore, John; Rosenheim, Brad; Leventer, Amy; Priscu, John", "repository": "USAP-DC", "science_program": null, "title": "CTD data from Mercer Subglacial Lake and access borehole", "url": "https://www.usap-dc.org/view/dataset/601657"}], "date_created": "Thu, 16 Jul 2020 00:00:00 GMT", "description": "The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.\u003cbr/\u003e\u003cbr/\u003eSubglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \\\"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\\\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.", "east": -149.50134, "geometry": "POINT(-156.55617 -84.4878585)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENTS; Antarctica; ISOTOPES; Subglacial Lake; USAP-DC; VIRUSES; PALEOCLIMATE RECONSTRUCTIONS; BACTERIA/ARCHAEA; LABORATORY; Radiocarbon; Whillans Ice Stream; AMD; SALSA; ECOSYSTEM FUNCTIONS; RADIOCARBON; FIELD INVESTIGATION; ICE MOTION; Mercer Ice Stream; Amd/Us; USA/NSF; GLACIERS/ICE SHEETS", "locations": "Antarctica; Mercer Ice Stream; Whillans Ice Stream", "north": -84.33543, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Instrumentation and Support; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Rosenheim, Brad; Fricker, Helen; Priscu, John; Leventer, Amy; Dore, John; Lyons, W. Berry; Christner, Brent", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "GenBank; NCBI GenBank; OSU-MGR; UNAVCO; USAP-DC", "science_programs": null, "south": -84.640287, "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "uid": "p0010119", "west": -163.611}, {"awards": "1543483 Sedwick, Peter", "bounds_geometry": "POLYGON((-180 -66,-179.5 -66,-179 -66,-178.5 -66,-178 -66,-177.5 -66,-177 -66,-176.5 -66,-176 -66,-175.5 -66,-175 -66,-175 -67.2,-175 -68.4,-175 -69.6,-175 -70.8,-175 -72,-175 -73.2,-175 -74.4,-175 -75.6,-175 -76.8,-175 -78,-175.5 -78,-176 -78,-176.5 -78,-177 -78,-177.5 -78,-178 -78,-178.5 -78,-179 -78,-179.5 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.8,165 -75.6,165 -74.4,165 -73.2,165 -72,165 -70.8,165 -69.6,165 -68.4,165 -67.2,165 -66,166.5 -66,168 -66,169.5 -66,171 -66,172.5 -66,174 -66,175.5 -66,177 -66,178.5 -66,-180 -66))", "dataset_titles": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle; NBP1704 Expedition Data", "datasets": [{"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}, {"dataset_uid": "200150", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "url": "https://www.bco-dmo.org/project/815403"}], "date_created": "Mon, 22 Jun 2020 00:00:00 GMT", "description": "The waters of the Ross Sea continental shelf are among the most productive in the Southern Ocean, and may comprise a significant regional oceanic sink for atmospheric carbon dioxide. In this region, primary production can be limited by the supply of dissolved iron to surface waters during the growing season. Water-column observations, sampling and measurements are to be carried out in the late autumn-early winter time frame on the Ross Sea continental shelf and coastal polynyas (Terra Nova Bay and Ross Ice Shelf polynyas), in order to better understand what drives the biogeochemical redistribution of micronutrient iron species during the onset of convective mixing and sea-ice formation at this time of year, thereby setting conditions for primary production during the following spring. The spectacular field setting and remote, hostile conditions that accompany the proposed field study present exciting possibilities for STEM education and training. At the K-12 level, the project seeks to support the development of educational outreach materials targeting elementary and middle school students, pre-service science teachers, and in-service science teachers.", "east": 165.0, "geometry": "POINT(175 -72)", "instruments": null, "is_usap_dc": true, "keywords": "POLYNYAS; USAP-DC; NBP1704; Iron; Ross Sea; TRACE ELEMENTS; SALINITY/DENSITY; R/V NBP; MARINE ECOSYSTEMS; BIOGEOCHEMICAL CYCLES", "locations": "Ross Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sedwick, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -78.0, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "uid": "p0010111", "west": -175.0}, {"awards": "1551195 Burdige, David", "bounds_geometry": "POLYGON((-71 -64,-70.1 -64,-69.2 -64,-68.3 -64,-67.4 -64,-66.5 -64,-65.6 -64,-64.7 -64,-63.8 -64,-62.9 -64,-62 -64,-62 -64.4,-62 -64.8,-62 -65.2,-62 -65.6,-62 -66,-62 -66.4,-62 -66.8,-62 -67.2,-62 -67.6,-62 -68,-62.9 -68,-63.8 -68,-64.7 -68,-65.6 -68,-66.5 -68,-67.4 -68,-68.3 -68,-69.2 -68,-70.1 -68,-71 -68,-71 -67.6,-71 -67.2,-71 -66.8,-71 -66.4,-71 -66,-71 -65.6,-71 -65.2,-71 -64.8,-71 -64.4,-71 -64))", "dataset_titles": "Expedition data of NBP1601; Project: Organic Carbon Oxidation and Iron Remobilization by West Antarctic Shelf Sediments", "datasets": [{"dataset_uid": "002665", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1601", "url": "https://www.rvdata.us/search/cruise/NBP1601"}, {"dataset_uid": "200148", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Project: Organic Carbon Oxidation and Iron Remobilization by West Antarctic Shelf Sediments", "url": "https://www.bco-dmo.org/project/806864"}], "date_created": "Tue, 16 Jun 2020 00:00:00 GMT", "description": "This project investigated the distribution of dissolved and solid phase iron in sediments along the western edge of the Antarctic Peninsula (i.e., the West Antarctic Shelf), as well as the biogeochemical processes occurring in these sediments that exert a major control on sediment iron distributions. In many coastal and continental margin regions, including those along the west side of the Antarctic Peninsula, sediments appear to represent a potentially important, but poorly quantified, source of iron to the overlying water column to support primary productivity. Sediment concentrations of iron are high (relative to those in seawater), and a number of different processes in the sediments may allow iron to \u201cleak\u201d from the sediments to the overlying waters, which could then support productivity driven by this \u201crecycled\u201d iron. ", "east": -62.0, "geometry": "POINT(-66.5 -66)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; Iron Remobilization; R/V NBP; NBP1601; SEDIMENT CHEMISTRY; USAP-DC; West Antarctic Shelf", "locations": "West Antarctic Shelf", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Burdige, David; Christensen, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -68.0, "title": "Organic carbon oxidation and iron remobilization by West Antarctic shelf sediments ", "uid": "p0010108", "west": -71.0}, {"awards": "1643722 Brook, Edward J.", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "South Pole Ice Core Methane Data and Gas Age Time Scale; South Pole ice core (SPC14) total air content (TAC)", "datasets": [{"dataset_uid": "601546", "doi": "10.15784/601546", "keywords": "Antarctica; South Pole", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) total air content (TAC)", "url": "https://www.usap-dc.org/view/dataset/601546"}, {"dataset_uid": "601329", "doi": "10.15784/601329", "keywords": "Antarctica; Gas Chromatography; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; South Pole", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Methane Data and Gas Age Time Scale", "url": "https://www.usap-dc.org/view/dataset/601329"}], "date_created": "Tue, 02 Jun 2020 00:00:00 GMT", "description": "This award supports a project to measure the concentration of the gas methane in air trapped in an ice core collected from the South Pole. The data will provide an age scale (age as a function of depth) by matching the South Pole methane changes with similar data from other ice cores for which the age vs. depth relationship is well known. The ages provided will allow all other gas measurements made on the South Pole core (by the PI and other NSF supported investigators) to be interpreted accurately as a function of time. This is critical because a major goal of the South Pole coring project is to understand the history of rare gases in the atmosphere like carbon monoxide, carbon dioxide, ethane, propane, methyl chloride, and methyl bromide. Relatively little is known about what controls these gases in the atmosphere despite their importance to atmospheric chemistry and climate. Undergraduate assistants will work on the project and be introduced to independent research through their work. The PI will continue visits to local middle schools to introduce students to polar science, and other outreach activities (e.g. laboratory tours, talks to local civic or professional organizations) as part of the project. \u003cbr/\u003e\u003cbr/\u003eMethane concentrations from a major portion (2 depth intervals, excluding the brittle ice-zone which is being measured at Penn State University) of the new South Pole ice core will be used to create a gas chronology by matching the new South Pole ice core record with that from the well-dated WAIS Divide ice core record. In combination with measurements made at Penn State, this will provide gas dating for the entire 50,000-year record. Correlation will be made using a simple but powerful mid-point method that has been previously demonstrated, and other methods of matching records will be explored. The intellectual merit of this work is that the gas chronology will be a fundamental component of this ice core project, and will be used by the PI and other investigators for dating records of atmospheric composition, and determining the gas age-ice age difference independently of glaciological models, which will constrain processes that affected firn densification in the past. The methane data will also provide direct stratigraphic markers of important perturbations to global biogeochemical cycles (e.g., rapid methane variations synchronous with abrupt warming and cooling in the Northern Hemisphere) that will tie other ice core gas records directly to those perturbations. A record of the total air content will also be produced as a by-product of the methane measurements and will contribute to understanding of this parameter. The broader impacts include that the work will provide a fundamental data set for the South Pole ice core project and the age scale (or variants of it) will be used by all other investigators working on gas records from the core. The project will employ an undergraduate assistant(s) in both years who will conduct an undergraduate research project which will be part of the student\u0027s senior thesis or other research paper. The project will also offer at least one research position for the Oregon State University Summer REU site program. Visits to local middle schools, and other outreach activities (e.g. laboratory tours, talks to local civic or professional organizations) will also be part of the project.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "AMD; LABORATORY; METHANE; ICE CORE RECORDS; Gas Chromatography; South Pole; USAP-DC", "locations": "South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "A High Resolution Atmospheric Methane Record from the South Pole Ice Core", "uid": "p0010102", "west": 0.0}, {"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": "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": "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": "Severinghaus, Jeffrey P.; Kalk, Michael; Hood, Ekaterina; Fudge, T. J.; Osterberg, Erich; Winski, Dominic A.; Ferris, David G.; Kennedy, Joshua A.; Steig, Eric J.; Kreutz, Karl; Aydin, Murat; Edwards, Jon S.; Buizert, Christo; Brook, Edward J.; Epifanio, Jenna; Kahle, Emma; Sowers, Todd A.", "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": "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.\u003cbr/\u003e\u003cbr/\u003eThe 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": "1643684 Saito, Mak; 1644073 DiTullio, Giacomo", "bounds_geometry": "POLYGON((-180 -72,-173.6 -72,-167.2 -72,-160.8 -72,-154.4 -72,-148 -72,-141.6 -72,-135.2 -72,-128.8 -72,-122.4 -72,-116 -72,-116 -72.7,-116 -73.4,-116 -74.1,-116 -74.8,-116 -75.5,-116 -76.2,-116 -76.9,-116 -77.6,-116 -78.3,-116 -79,-122.4 -79,-128.8 -79,-135.2 -79,-141.6 -79,-148 -79,-154.4 -79,-160.8 -79,-167.2 -79,-173.6 -79,180 -79,178 -79,176 -79,174 -79,172 -79,170 -79,168 -79,166 -79,164 -79,162 -79,160 -79,160 -78.3,160 -77.6,160 -76.9,160 -76.2,160 -75.5,160 -74.8,160 -74.1,160 -73.4,160 -72.7,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,172 -72,174 -72,176 -72,178 -72,-180 -72))", "dataset_titles": "Algal pigment concentrations from the Ross Sea; Biogenic silica concentrations from the Ross Sea; NBP1801 Expedition data; Nutrients from NBP18-01 CICLOPS", "datasets": [{"dataset_uid": "601205", "doi": "10.15784/601205", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Chlorophyll; Chromatography; Liquid Chromatograph; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Seawater Measurements; Southern Ocean; Water Measurements; Water Samples", "people": "Ditullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Algal pigment concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601205"}, {"dataset_uid": "601225", "doi": "10.15784/601225", "keywords": "Antarctica; Biogenic Silica; Biogenic Silica Concentrations; Chemistry:Water; Geochemistry; NBP1801; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Southern Ocean; Spectroscopy; Water Measurements; Water Samples", "people": "Ditullio, Giacomo; Schanke, Nicole", "repository": "USAP-DC", "science_program": null, "title": "Biogenic silica concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601225"}, {"dataset_uid": "200056", "doi": "10.7284/907753", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1801 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1801"}, {"dataset_uid": "601428", "doi": "10.15784/601428", "keywords": "Amundsen Sea; Antarctica; NBP1801; Nitrate; Nitrite; Nutrients; Phosphate; Ross Sea; R/v Nathaniel B. Palmer; Silicic Acid; Terra Nova Bay", "people": "Saito, Mak", "repository": "USAP-DC", "science_program": null, "title": "Nutrients from NBP18-01 CICLOPS", "url": "https://www.usap-dc.org/view/dataset/601428"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations. \u003cbr/\u003e\u003cbr/\u003eThe study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems.", "east": 160.0, "geometry": "POINT(-158 -75.5)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; NBP1801; Amd/Us; USA/NSF; USAP-DC; NUTRIENTS; PIGMENTS; CHLOROPHYLL; R/V NBP; Ross Sea; AMD", "locations": "Ross Sea", "north": -72.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "DiTullio, Giacomo; Lee, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -79.0, "title": "Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay", "uid": "p0010045", "west": -116.0}, {"awards": "1401489 Sigman, Daniel", "bounds_geometry": "POLYGON((-180 -45,-144 -45,-108 -45,-72 -45,-36 -45,0 -45,36 -45,72 -45,108 -45,144 -45,180 -45,180 -47.5,180 -50,180 -52.5,180 -55,180 -57.5,180 -60,180 -62.5,180 -65,180 -67.5,180 -70,144 -70,108 -70,72 -70,36 -70,0 -70,-36 -70,-72 -70,-108 -70,-144 -70,-180 -70,-180 -67.5,-180 -65,-180 -62.5,-180 -60,-180 -57.5,-180 -55,-180 -52.5,-180 -50,-180 -47.5,-180 -45))", "dataset_titles": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age; Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.; Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.; GOSHIP section IO8S and P18S", "datasets": [{"dataset_uid": "200049", "doi": "doi.org/10.1594/PANGAEA.848271", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.", "url": "https://doi.org/10.1594/PANGAEA.848271"}, {"dataset_uid": "200048", "doi": "doi.pangaea.de/10.1594/PANGAEA.891436.", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.", "url": "https://doi.pangaea.de/10.1594/PANGAEA.891436"}, {"dataset_uid": "200051", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age", "url": "https://www.pnas.org/content/suppl/2017/03/14/1615718114.DCSupplemental"}, {"dataset_uid": "200050", "doi": "", "keywords": null, "people": null, "repository": "CLIVAR", "science_program": null, "title": "GOSHIP section IO8S and P18S", "url": "https://cchdo.ucsd.edu/"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "ABSTRACT\u003cbr/\u003eIntellectual Merit:\u003cbr/\u003eThe high concentration of the major nutrients nitrate and phosphate is a fundamental characteristic of the Antarctic Zone in the Southern Ocean and is central to its role in global ocean fertility and the global carbon cycle. The isotopic composition of diatom-bound organic nitrogen is one of the best hopes for reconstructing the nutrient status of polar surface waters over glacial cycles, which in turn may hold the explanation for the decline in atmospheric carbon dioxide during ice ages. The PIs propose to generate detailed diatom-bound nitrogen isotope (\u0026#948;15Ndb) records from high sedimentation rate cores from the Kerguelen Plateau. Because the cores were collected at relatively shallow seafloor depths, they have adequate planktonic and benthic foraminifera to develop accurate age models. The resulting data could be compared with climate records from Antarctic ice cores and other archives to investigate climate-related changes, including the major steps into and out of ice ages and the millennial-scale events that occur during ice ages and at their ends. The records generated in this project will provide a critical test of hypotheses for the cause of lower ice age CO2.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThis study will contribute to the goal of understanding ice ages and past CO2 changes, which both have broad implications for future climate. Undergraduates will undertake summer internships, with the possibility of extending their work into junior year projects and senior theses. In addition, the PI will lead modules for two Princeton programs for middle school teachers and will host a teacher for a six-week summer research project.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; South Pacific Ocean; USAP-DC; NOT APPLICABLE", "locations": "South Pacific Ocean", "north": -45.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sigman, Daniel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "PANGAEA", "repositories": "CLIVAR; PANGAEA; Publication", "science_programs": null, "south": -70.0, "title": "High-resolution, Assemblage-specific Records of Diatom-bound N Isotopes from the Indian Sector of the Antarctic Ocean", "uid": "p0010046", "west": -180.0}, {"awards": "1744645 Young, Jodi", "bounds_geometry": "POLYGON((-64.4 -64.2,-64.38 -64.2,-64.36 -64.2,-64.34 -64.2,-64.32 -64.2,-64.3 -64.2,-64.28 -64.2,-64.26 -64.2,-64.24 -64.2,-64.22 -64.2,-64.2 -64.2,-64.2 -64.26,-64.2 -64.32,-64.2 -64.38,-64.2 -64.44,-64.2 -64.5,-64.2 -64.56,-64.2 -64.62,-64.2 -64.68,-64.2 -64.74,-64.2 -64.8,-64.22 -64.8,-64.24 -64.8,-64.26 -64.8,-64.28 -64.8,-64.3 -64.8,-64.32 -64.8,-64.34 -64.8,-64.36 -64.8,-64.38 -64.8,-64.4 -64.8,-64.4 -64.74,-64.4 -64.68,-64.4 -64.62,-64.4 -64.56,-64.4 -64.5,-64.4 -64.44,-64.4 -64.38,-64.4 -64.32,-64.4 -64.26,-64.4 -64.2))", "dataset_titles": "Dataset: Particulate Organic Carbon and Particulate Nitrogen; Dataset: Photosynthetic Pigments; Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume; Sea-ice diatom compatible solute shifts", "datasets": [{"dataset_uid": "200377", "doi": "10.26008/1912/bco-dmo.913222.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Photosynthetic Pigments", "url": "https://www.bco-dmo.org/dataset/913222"}, {"dataset_uid": "200322", "doi": "10.21228/M84386", "keywords": null, "people": null, "repository": "Metabolomics workbench", "science_program": null, "title": "Sea-ice diatom compatible solute shifts", "url": "https://www.metabolomicsworkbench.org/data/DRCCMetadata.php?Mode=Study\u0026StudyID=ST001393"}, {"dataset_uid": "200378", "doi": "10.26008/1912/bco-dmo.913655.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume", "url": "https://www.bco-dmo.org/dataset/913655"}, {"dataset_uid": "200376", "doi": "10.26008/1912/bco-dmo.913566.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Particulate Organic Carbon and Particulate Nitrogen", "url": "https://www.bco-dmo.org/dataset/913566"}], "date_created": "Tue, 23 Jul 2019 00:00:00 GMT", "description": "Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eThere is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula.\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": -64.2, "geometry": "POINT(-64.3 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; SHIPS; DIATOMS; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -64.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Young, Jodi; Deming, Jody", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "BCO-DMO", "repositories": "BCO-DMO; Metabolomics workbench", "science_programs": null, "south": -64.8, "title": "Spring Blooms of Sea Ice Algae Along the Western Antarctic Peninsula: Effects of Warming and Freshening on Cell Physiology and Biogeochemical Cycles.", "uid": "p0010039", "west": -64.4}, {"awards": "1744849 Sokol, Eric; 1744785 Barrett, John; 1745053 Salvatore, Mark", "bounds_geometry": "POLYGON((162.92 -77.56,162.971 -77.56,163.022 -77.56,163.073 -77.56,163.124 -77.56,163.175 -77.56,163.226 -77.56,163.277 -77.56,163.328 -77.56,163.379 -77.56,163.43 -77.56,163.43 -77.571,163.43 -77.582,163.43 -77.593,163.43 -77.604,163.43 -77.615,163.43 -77.626,163.43 -77.637,163.43 -77.648,163.43 -77.659,163.43 -77.67,163.379 -77.67,163.328 -77.67,163.277 -77.67,163.226 -77.67,163.175 -77.67,163.124 -77.67,163.073 -77.67,163.022 -77.67,162.971 -77.67,162.92 -77.67,162.92 -77.659,162.92 -77.648,162.92 -77.637,162.92 -77.626,162.92 -77.615,162.92 -77.604,162.92 -77.593,162.92 -77.582,162.92 -77.571,162.92 -77.56))", "dataset_titles": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica, January 2018", "datasets": [{"dataset_uid": "200344", "doi": "10.6073/pasta/9acbbde9abc1e013f8c9fd9c383327f4", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica, January 2018", "url": "https://portal.edirepository.org/nis/mapbrowse?packageid=knb-lter-mcm.263.1"}], "date_created": "Wed, 03 Jul 2019 00:00:00 GMT", "description": "Microbial mats are found throughout the McMurdo Dry Valleys where summer snowmelt provides liquid water that allows these mats to flourish. Researchers have long studied the environmental conditions microbial mats need to grow. Despite these efforts, it has been difficult to develop a broad picture of these unique ecosystems. Recent advances in satellite technology now provide researchers an exciting new tool to study these special Antarctic ecosystems from space using the unique spectral signatures associated with microbial mats. This new technology not only offers the promise that microbial mats can be mapped and studied from space, this research will also help protect these delicate environments from potentially harmful human impacts that can occur when studying them from the ground. This project will use satellite imagery and spectroscopic techniques to identify and map microbial mat communities and relate their properties and distributions to both field and lab-based measurements. This research provides an exciting new tool to help document and understand the distribution of a major component of the Antarctic ecosystem in the McMurdo Dry Valleys.\r\n\r\nThe goal of this project is to establish quantitative relationships between spectral signatures derived from orbit and the physiological status and biogeochemical properties of microbial mat communities in Taylor Valley, Antarctica, as measured by field and laboratory analyses on collected samples. The goal will be met by (1) refining atmospheric correction techniques using in situ radiometric rectification to derive accurate surface spectra; (2) collecting multispectral orbital images concurrent with in situ sampling and spectral measurements in the field to ensure temporal comparability; (3) measuring sediment, water, and microbial mat samples for organic and inorganic carbon content, essential biogeochemical nutrients, and chlorophyll-a to determine relevant mat characteristics; and (4) quantitatively associating these laboratory-derived characteristics with field-derived and orbital spectral signatures and parameters. The result of this work will be a more robust quantitative link between the distribution of microbial mat communities and their biogeochemical properties to landscape-scale spectral signatures.\r\n\r\nThis 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": 163.43, "geometry": "POINT(163.175 -77.615)", "instruments": null, "is_usap_dc": true, "keywords": "RIVERS/STREAM; CYANOBACTERIA (BLUE-GREEN ALGAE); USAP-DC; Taylor Valley; INFRARED IMAGERY; WORLDVIEW-2; WORLDVIEW-3; Antarctica; FIELD INVESTIGATION; Amd/Us; ACTIVE LAYER", "locations": "Antarctica; Taylor Valley", "north": -77.56, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Salvatore, Mark; Barrett, John; Sokol, Eric", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e WORLDVIEW \u003e WORLDVIEW-2; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e WORLDVIEW \u003e WORLDVIEW-3", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -77.67, "title": "COLLABORATIVE RESEARCH: Remote Characterization of Microbial Mats in Taylor Valley, Antarctica, through In Situ Sampling and Spectral Validation", "uid": "p0010036", "west": 162.92}, {"awards": "1745036 Marchetti, Adrian; 1744760 Hopkinson, Brian", "bounds_geometry": "POLYGON((-77 -61,-75.2 -61,-73.4 -61,-71.6 -61,-69.8 -61,-68 -61,-66.2 -61,-64.4 -61,-62.6 -61,-60.8 -61,-59 -61,-59 -62.1,-59 -63.2,-59 -64.3,-59 -65.4,-59 -66.5,-59 -67.6,-59 -68.7,-59 -69.8,-59 -70.9,-59 -72,-60.8 -72,-62.6 -72,-64.4 -72,-66.2 -72,-68 -72,-69.8 -72,-71.6 -72,-73.4 -72,-75.2 -72,-77 -72,-77 -70.9,-77 -69.8,-77 -68.7,-77 -67.6,-77 -66.5,-77 -65.4,-77 -64.3,-77 -63.2,-77 -62.1,-77 -61))", "dataset_titles": "Photosynthetic physiological data of Proteorhodopsin containing diatoms under differing iron availabilities", "datasets": [{"dataset_uid": "601530", "doi": "10.15784/601530", "keywords": "Antarctica; Diatom", "people": "Marchetti, Adrian; Hopkinson, Brian; Plumb, Kaylie; Andrew, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Photosynthetic physiological data of Proteorhodopsin containing diatoms under differing iron availabilities", "url": "https://www.usap-dc.org/view/dataset/601530"}], "date_created": "Sun, 16 Jun 2019 00:00:00 GMT", "description": "Proteorhodopsins (PR) are retinal-binding membrane proteins that can act as light-driven proton pumps to generate energy that can be used for metabolism and growth. The discovery of PRs in many diverse marine prokaryotic microbes has initiated extensive investigations into their distributions and functional roles. Recently, a rhodopsin-like gene of the proton-pumping variety was identified in diatoms thus revealing their presence within obligate marine eukaryotic photoautotrophs. Since this time, PRs have been identified in a number of diatom isolates although there appears to be a much higher frequency of\r\nPR in diatoms residing in cold, iron-limited regions of the ocean, particularly in the Southern Ocean (SO). PR is especially suited for use in SO phytoplankton since unlike conventional photosynthesis, it uses no iron and its reaction rate is insensitive to temperature. The overall objective of our proposed project is to characterize Antarctic diatom-PR and determine its role in the adaptation of SO diatoms to the prevailing conditions of low iron concentrations and extremely low temperatures. Our research objectives will be achieved through a combination of molecular, biochemical and physiological measurements in diatom isolates recently obtained from the Western Antarctic Peninsula region. We will determine the proton-pumping characteristics and pumping rates of PR as a function of light intensity and wavelength, the resultant PR-linked intracellular ATP production rates, and the cellular localization of the protein. We will examine under which environmental conditions Antarctic diatom-PR is most highly expressed and construct a cellular energy budget that includes diatom-PR when grown under these different growth conditions. Estimates of the energy flux generated by PR in PR-containing diatoms will be compared to total energy generation by the photosynthetic light reactions and metabolically coupled respiration rates. Finally, we will compare the characteristics and gene expression of diatom-PR in Antarctic diatoms to PR-containing diatoms isolated from temperate regions in order to investigate if there is a preferential dependence on energy production through diatom-PR in diatoms residing in cold, iron-limited regions of the ocean.", "east": -59.0, "geometry": "POINT(-68 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; NSF/USA; Southern Ocean; AMD; Amd/Us; LABORATORY; USAP-DC; BIOGEOCHEMICAL CYCLES", "locations": "Southern Ocean", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Marchetti, Adrian; Septer, Alecia; Hopkinson, Brian", "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": -72.0, "title": "Collaborative research: Antarctic diatom proteorhodopsins: Characterization and a potential role in the iron-limitation response", "uid": "p0010033", "west": -77.0}, {"awards": "1637708 Gooseff, Michael", "bounds_geometry": "POLYGON((160 -77.25,160.5 -77.25,161 -77.25,161.5 -77.25,162 -77.25,162.5 -77.25,163 -77.25,163.5 -77.25,164 -77.25,164.5 -77.25,165 -77.25,165 -77.375,165 -77.5,165 -77.625,165 -77.75,165 -77.875,165 -78,165 -78.125,165 -78.25,165 -78.375,165 -78.5,164.5 -78.5,164 -78.5,163.5 -78.5,163 -78.5,162.5 -78.5,162 -78.5,161.5 -78.5,161 -78.5,160.5 -78.5,160 -78.5,160 -78.375,160 -78.25,160 -78.125,160 -78,160 -77.875,160 -77.75,160 -77.625,160 -77.5,160 -77.375,160 -77.25))", "dataset_titles": "EDI Data Portal: McMurdo Dry Valleys LTER; McMurdo Dry Valleys LTER Data Repository", "datasets": [{"dataset_uid": "200036", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys LTER Data Repository", "url": "http://mcm.lternet.edu/power-search/data-set"}, {"dataset_uid": "200037", "doi": "", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "EDI Data Portal: McMurdo Dry Valleys LTER", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM"}], "date_created": "Fri, 31 May 2019 00:00:00 GMT", "description": "The McMurdo Dry Valleys, Antarctica, are a mosaic of terrestrial and aquatic ecosystems in a cold desert. The McMurdo Long Term Ecological Research (LTER) project has been observing these ecosystems since 1993 and this award will support key long-term measurements, manipulation experiments, synthesis, and modeling to test current theories on ecosystem structure and function. Data collection is focused on meteorology and physical and biological dimensions of soils, streams, lakes, glaciers, and permafrost. The long-term measurements show that biological communities have adapted to the seasonally cold, dark, and arid conditions that prevail for all but a short period in the austral summer. Physical (climate and geological) drivers impart a dynamic connectivity among portions of the Dry Valley landscape over seasonal to millennial time scales. For instance, lakes and soils have been connected through cycles of lake-level rise and fall over the past 20,000 years while streams connect glaciers to lakes over seasonal time scales. Overlaid upon this physical system are biotic communities that are structured by the environment and by the movement of individual organisms within and between the glaciers, streams, lakes, and soils. The new work to be conducted at the McMurdo LTER site will explore how the layers of connectivity in the McMurdo Dry Valleys influence ecosystem structure and function. \r\n\r\nThis project will test the hypothesis that increased ecological connectivity following enhanced melt conditions within the McMurdo Dry Valleys ecosystem will amplify exchange of biota, energy, and matter, homogenizing ecosystem structure and functioning. This hypothesis will be tested with new and continuing experiments that examine: 1) how climate variation alters connectivity among landscape units, and 2) how biota are connected across a heterogeneous landscape using state-of-the-science tools and methods including automated sensor networks, analysis of seasonal satellite imagery, biogeochemical analyses, and next-generation sequencing. McMurdo LTER education programs and outreach activities will be continued, and expanded with new programs associated with the 200th anniversary of the first recorded sightings of Antarctica. These activities will advance societal understanding of how polar ecosystems respond to change. McMurdo 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 lead the development of international environmental stewardship protocols for human activities in the region.", "east": 165.0, "geometry": "POINT(162.5 -77.875)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; NOT APPLICABLE; Antarctica; RIVERS/STREAM; USAP-DC; TERRESTRIAL ECOSYSTEMS; LAKE/POND; Polar", "locations": "Antarctica; Polar", "north": -77.25, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Gooseff, Michael N.; Takacs-Vesbach, Cristina; Howkins, Adrian; McKnight, Diane; Doran, Peter; Adams, Byron; Barrett, John; Morgan-Kiss, Rachael; Priscu, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "LTER", "repositories": "EDI; LTER", "science_programs": "LTER", "south": -78.5, "title": "LTER: Ecosystem Response to Amplified Landscape Connectivity in the McMurdo Dry Valleys, Antarctica", "uid": "p0010031", "west": 160.0}, {"awards": "1642570 Thurber, Andrew", "bounds_geometry": "POINT(166.666 -77.8)", "dataset_titles": "Microbial community composition of the Cinder Cones Cold Seep", "datasets": [{"dataset_uid": "200035", "doi": "DOI:10.1575/1912/bco-dmo.756997.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Microbial community composition of the Cinder Cones Cold Seep", "url": "https://www.bco-dmo.org/dataset/756997"}], "date_created": "Fri, 24 May 2019 00:00:00 GMT", "description": "Methane is a potent greenhouse gas that is naturally emitted into the oceans by geologic seeps and microbial production. Based on studies of persistent deep-sea seeps at mid- and northern latitudes, researchers have learned that bacteria and archaea can create a \"sediment filter\" that oxidizes methane prior to its release. Antarctica is thought to contain large reservoirs of organic carbon buried beneath its ice which could a quantity of methane equivalent to all of the permafrost in the Arctic and yet we know almost nothing about the methane oxidizing microbes in this region. How these microbial communities develop and potentially respond to fluctuations in methane levels is an under-explored avenue of research. A bacterial mat was recently discovered at 78 degrees south, suggesting the possible presence of a methane seep, and associated microbial communities. This project will explore this environment in detail to assess the levels and origin of methane, and the nature of the microbial ecosystem present. \u003cbr/\u003e \u003cbr/\u003eAn expansive bacterial mat appeared and/or was discovered at 78 degrees south in 2011. This site, near McMurdo Station Antarctica, has been visited since the mid-1960s, but this mat was not observed until 2011. The finding of this site provides an unusual opportunity to study an Antarctic marine benthic habitat with active methane cycling and to examine the dynamics of recruitment and community succession of seep fauna including bacteria, archaea, protists and metazoans. This project will collect the necessary baseline data to facilitate further studies of Antarctic methane cycling. The concentration and source of methane will be determined at this site and at potentially analogous sites in McMurdo Sound. In addition to biogeochemical characterization of the sites, molecular analysis of the microbial community will quantify the time scales on which bacteria and archaea respond to methane input and provide information on rates of community development and succession in the Southern Ocean. Project activities will facilitate the training of at least one graduate student and results will be shared at both local and international levels. A female graduate student will be mentored as part of this project and data collected will form part of her dissertation. Lectures will be given in K-12 classrooms in Oregon to excite students about polar science. National and international audiences will be reached through blogs and presentations at a scientific conference. The PI\u0027s previous blogs have been used by K-12 classrooms as part of their lesson plans and followed in over 65 countries.\u003cbr/\u003e", "east": 166.666, "geometry": "POINT(166.666 -77.8)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Sea Floor; USAP-DC; Ross Sea; BACTERIA/ARCHAEA; NOT APPLICABLE", "locations": "Ross Sea; Sea Floor", "north": -77.8, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Thurber, Andrew", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -77.8, "title": "EAGER: Elucidating the Antarctic Methane Cycle at the Cinder Cones Reducing Habitat.", "uid": "p0010030", "west": 166.666}, {"awards": "1341479 Marchetti, Adrian", "bounds_geometry": "POLYGON((-72.8 -48,-67.12 -48,-61.44 -48,-55.76 -48,-50.08 -48,-44.4 -48,-38.72 -48,-33.04 -48,-27.36 -48,-21.68 -48,-16 -48,-16 -50.02,-16 -52.04,-16 -54.06,-16 -56.08,-16 -58.1,-16 -60.12,-16 -62.14,-16 -64.16,-16 -66.18,-16 -68.2,-21.68 -68.2,-27.36 -68.2,-33.04 -68.2,-38.72 -68.2,-44.4 -68.2,-50.08 -68.2,-55.76 -68.2,-61.44 -68.2,-67.12 -68.2,-72.8 -68.2,-72.8 -66.18,-72.8 -64.16,-72.8 -62.14,-72.8 -60.12,-72.8 -58.1,-72.8 -56.08,-72.8 -54.06,-72.8 -52.04,-72.8 -50.02,-72.8 -48))", "dataset_titles": "16S and 18S Sequence data; Fragilariopsis kerguelensis iron and light transcriptomes; Physiology and transcriptomes of polar isolates; Polar isolate transcriptomes; Sequence data from Ocean Station Papa seawater ; Sequence data RNA-Seq of marine phytoplankton: FeB12", "datasets": [{"dataset_uid": "200016", "doi": "", "keywords": null, "people": null, "repository": "iMicrobe", "science_program": null, "title": "Fragilariopsis kerguelensis iron and light transcriptomes", "url": "https://www.imicrobe.us/#/projects/104"}, {"dataset_uid": "200019", "doi": "", "keywords": null, "people": null, "repository": "Cyverse Data Commons", "science_program": null, "title": "Polar isolate transcriptomes", "url": "http://datacommons.cyverse.org/search/?search_term=unc_phyto_isolates"}, {"dataset_uid": "200018", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Sequence data from Ocean Station Papa seawater ", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP006906"}, {"dataset_uid": "200017", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Sequence data RNA-Seq of marine phytoplankton: FeB12", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP074366"}, {"dataset_uid": "200021", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "16S and 18S Sequence data", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA299401"}, {"dataset_uid": "200020", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Physiology and transcriptomes of polar isolates", "url": "https://www.bco-dmo.org/project/653229"}], "date_created": "Mon, 11 Mar 2019 00:00:00 GMT", "description": "The Southern Ocean surrounding Antarctica is changing rapidly in response to Earth\u0027s warming climate. These changes will undoubtedly influence communities of primary producers (the organisms at the base of the food chain, particularly plant-like organisms using sunlight for energy) by altering conditions that influence their growth and composition. Because primary producers such as phytoplankton play an important role in global biogeochemical cycling, it is essential to understand how they will respond to changes in their environment. The growth of phytoplankton in certain regions of the Southern Ocean is constrained by steep gradients in chemical and physical properties that vary in both space and time. Light and iron have been identified as key variables influencing phytoplankton abundance and distribution within Antarctic waters. Microscopic algae known as diatoms are dominant members of the phytoplankton and sea ice communities, accounting for significant proportions of primary production. The overall objective of this project is to identify the molecular bases for the physiological responses of polar diatoms to varying light and iron conditions. The project should provide a means of evaluating the extent these factors regulate diatom growth and influence net community productivity in Antarctic waters. Although numerous studies have investigated how polar diatoms are affected by varying light and iron, the cellular mechanisms leading to their distinct physiological responses remain unknown. We observed several growth responses, but a majority of polar diatom growth rates and photophysiology did not appear to be co-limited by iron and light limitation. Using comparative transcriptomics, we have examined the expression patterns of key genes and metabolic pathways in several ecologically important polar diatoms isolated from Antarctic waters and grown under varying iron and irradiance conditions. In addition, molecular indicators for iron and light limitation will be developed within these polar diatoms through the identification of iron- and light-responsive genes -- the expression patterns of which can be used to determine their physiological status. Upon verification in laboratory cultures, these indicators will be utilized by way of metatranscriptomic sequencing to examine iron and light limitation in natural diatom assemblages collected along environmental gradients in Western Antarctic Peninsula waters. In order to fully understand the role phytoplankton play in Southern Ocean biogeochemical cycles, dependable methods that provide a means of elucidating the physiological status of phytoplankton at any given time and location are essential.", "east": -16.0, "geometry": "POINT(-44.4 -58.1)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; AQUATIC SCIENCES; PHYTOPLANKTON; USAP-DC; Southern Ocean; Sea Surface; DIATOMS", "locations": "Sea Surface; Southern Ocean", "north": -48.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Marchetti, Adrian", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "iMicrobe", "repositories": "BCO-DMO; Cyverse Data Commons; iMicrobe; NCBI GenBank", "science_programs": null, "south": -68.2, "title": "Iron and Light Limitation in Ecologically Important Polar Diatoms: Comparative Transcriptomics and Development of Molecular Indicators", "uid": "p0010018", "west": -72.8}, {"awards": "1443705 Vernet, Maria; 1443680 Smith, Craig; 1443733 Winsor, Peter", "bounds_geometry": "POLYGON((-66 -64,-65.6 -64,-65.2 -64,-64.8 -64,-64.4 -64,-64 -64,-63.6 -64,-63.2 -64,-62.8 -64,-62.4 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.4 -65,-62.8 -65,-63.2 -65,-63.6 -65,-64 -65,-64.4 -65,-64.8 -65,-65.2 -65,-65.6 -65,-66 -65,-66 -64.9,-66 -64.8,-66 -64.7,-66 -64.6,-66 -64.5,-66 -64.4,-66 -64.3,-66 -64.2,-66 -64.1,-66 -64))", "dataset_titles": "Andvord Bay Glacier Timelapse; Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603); Expedition Data; Expedition data of LMG1702; FjordEco Phytoplankton Ecology Dataset in Andvord Bay ; Fjord-Eco Sediment OrgC OrgN Data - Craig Smith; LMG1510 Expedition data; NBP1603 Expedition data; Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf", "datasets": [{"dataset_uid": "601193", "doi": "10.15784/601193", "keywords": "Antarctica; Geochronology; Grain Size; LMG1510; NBP1603; Sediment; Sediment Core Data", "people": "Homolka, Khadijah; Eidam, Emily; Smith, Craig; Nittrouer, Charles", "repository": "USAP-DC", "science_program": null, "title": "Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)", "url": "https://www.usap-dc.org/view/dataset/601193"}, {"dataset_uid": "200039", "doi": "10.7284/907205", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1603 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1603"}, {"dataset_uid": "200040", "doi": "10.7284/907085", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG1510 Expedition data", "url": "https://www.rvdata.us/search/cruise/LMG1510"}, {"dataset_uid": "601111", "doi": "10.15784/601111", "keywords": "Antarctica; Antarctic Peninsula; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iceberg; Photo; Photo/video; Photo/Video", "people": "Winsor, Peter; Truffer, Martin", "repository": "USAP-DC", "science_program": "FjordEco", "title": "Andvord Bay Glacier Timelapse", "url": "https://www.usap-dc.org/view/dataset/601111"}, {"dataset_uid": "002733", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1702", "url": "https://www.rvdata.us/search/cruise/LMG1702"}, {"dataset_uid": "001366", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1702"}, {"dataset_uid": "000402", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1702"}, {"dataset_uid": "601157", "doi": "10.15784/601157", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Snow/ice; Snow/Ice", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "FjordEco", "title": "Fjord-Eco Sediment OrgC OrgN Data - Craig Smith", "url": "https://www.usap-dc.org/view/dataset/601157"}, {"dataset_uid": "601158", "doi": "10.15784/601158", "keywords": "Antarctica; Antarctic Peninsula; Biota; Ecology; Fjord; Phytoplankton", "people": "Pan, B. Jack; Vernet, Maria; Forsch, Kiefer; Manck, Lauren", "repository": "USAP-DC", "science_program": "FjordEco", "title": "FjordEco Phytoplankton Ecology Dataset in Andvord Bay ", "url": "https://www.usap-dc.org/view/dataset/601158"}, {"dataset_uid": "601236", "doi": "10.15784/601236", "keywords": "Abundance; Andvord Bay; Antarctica; Antarctic Peninsula; Biota; Fjord; LMG1510; Marine Sediments; Oceans; Polychaete; Polychaete Family Richness; R/v Laurence M. Gould; Sediment Core Data; Sediment Macrofauna", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "FjordEco", "title": "Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf", "url": "https://www.usap-dc.org/view/dataset/601236"}], "date_created": "Wed, 13 Feb 2019 00:00:00 GMT", "description": "Marine communities along the western Antarctic Peninsula are highly productive ecosystems which support a diverse assemblage of charismatic animals such as penguins, seals, and whales as well as commercial fisheries such as that on Antarctic krill. Fjords (long, narrow, deep inlets of the sea between high cliffs) along the central coast of the Peninsula appear to be intense, potentially climate sensitive, hotspots of biological production and biodiversity, yet the structure and dynamics of these fjord ecosystems are very poorly understood. Because of this intense biological activity and the charismatic fauna it supports, these fjords are also major destinations for a large Antarctic tourism industry. This project is an integrated field and modeling program to evaluate physical oceanographic processes, glacial inputs, water column community dynamics, and seafloor bottom community structure and function in these important yet little understood fjord systems. These Antarctic fjords have characteristics that are substantially different from well-studied Arctic fjords, likely yielding much different responses to climate warming. This project will provide major new insights into the dynamics and climate sensitivity of Antarctic fjord ecosystems, highlighting contrasts with Arctic sub-polar fjords, and potentially transforming our understanding of the ecological role of fjords in the rapidly warming west Antarctic coastal marine landscape. The project will also further the NSF goal of training new generations of scientists, providing scientific training for undergraduate, graduate, and postdoctoral students. This includes the unique educational opportunity for undergraduates to participate in research cruises in Antarctica and the development of a novel summer graduate course on fjord ecosystems. Internet based outreach activities will be enhanced and extended by the participation of a professional photographer who will produce magazine articles, websites, radio broadcasts, and other forms of public outreach on the fascinating Antarctic ecosystem. \u003cbr/\u003e\u003cbr/\u003eThis project will involve a 15-month field program to test mechanistic hypotheses concerning oceanographic and glaciological forcing, and phytoplankton and benthic community response in the Antarctic fjords. Those efforts will be followed by a coupled physical/biological modeling effort to evaluate the drivers of biogeochemical cycles in the fjords and to explore their potential sensitivity to enhanced meltwater and sediment inputs. Fieldwork over two oceanographic cruises will utilize moorings, weather stations, and glacial, sea-ice and seafloor time-lapse cameras to obtain an integrated view of fjord ecosystem processes. The field team will also make multiple shipboard measurements and will use towed and autonomous underwater vehicles to intensively evaluate fjord ecosystem structure and function during spring/summer and autumn seasons. These integrated field and modeling studies are expected to elucidate fundamental properties of water column and sea bottom ecosystem structure and function in the fjords, and to identify key physical-chemical-glaciological forcing in these rapidly warming ecosystems.", "east": -62.0, "geometry": "POINT(-64 -64.5)", "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": "OCEAN CURRENTS; Bellingshausen Sea; LMG1702; COMMUNITY DYNAMICS; FJORDS; R/V LMG; MARINE ECOSYSTEMS; USAP-DC; ECOSYSTEM FUNCTIONS; ANIMALS/INVERTEBRATES; SEDIMENTATION; NOT APPLICABLE; BENTHIC", "locations": "Bellingshausen Sea", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Winsor, Peter; Truffer, Martin; Smith, Craig; Powell, Brian; Merrifield, Mark; Vernet, Maria; Kohut, Josh", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": "FjordEco", "south": -65.0, "title": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)", "uid": "p0010010", "west": -66.0}, {"awards": "1443464 Sowers, Todd; 1443710 Severinghaus, Jeffrey; 1443472 Brook, Edward J.", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "South Pole CH4 data for termination; South Pole Ice Core Isotopes of N2 and Ar; South Pole ice core (SPC14) discrete methane data; South Pole ice core total air content; South Pole (SPICECORE) 15N, 18O, O2/N2 and Ar/N2; SP19 Gas Chronology", "datasets": [{"dataset_uid": "601517", "doi": "10.15784/601517", "keywords": "Antarctica; Argon; Argon Isotopes; Firn; Firn Temperature Gradient; Firn Thickness; Gas Isotopes; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Nitrogen; Nitrogen Isotopes; South Pole; SPICEcore", "people": "Morgan, Jacob; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Isotopes of N2 and Ar", "url": "https://www.usap-dc.org/view/dataset/601517"}, {"dataset_uid": "601231", "doi": "10.15784/601231", "keywords": "Air Content; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Snow/ice; Snow/Ice; South Pole; SPICEcore", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core total air content", "url": "https://www.usap-dc.org/view/dataset/601231"}, {"dataset_uid": "601230", "doi": "10.15784/601230", "keywords": "Antarctica; Atmospheric CH4; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Data; Methane; Methane Concentration; Snow/ice; Snow/Ice; South Pole; SPICEcore", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole CH4 data for termination", "url": "https://www.usap-dc.org/view/dataset/601230"}, {"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": "601152", "doi": "10.15784/601152", "keywords": "Antarctica; Antarctic Ice Sheet; Chemistry:gas; Chemistry:Gas; Chemistry:ice; Chemistry:Ice; Delta 18O; Dole Effect; Firn Thickness; Gas Isotopes; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Gravitational Settling; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; Inert Gases; Nitrogen; Nitrogen Isotopes; Oxygen; Oxygen Isotope; Snow/ice; Snow/Ice; South Pole; SPICEcore", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPICECORE) 15N, 18O, O2/N2 and Ar/N2", "url": "https://www.usap-dc.org/view/dataset/601152"}, {"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": "Severinghaus, Jeffrey P.; Kalk, Michael; Hood, Ekaterina; Fudge, T. J.; Osterberg, Erich; Winski, Dominic A.; Ferris, David G.; Kennedy, Joshua A.; Steig, Eric J.; Kreutz, Karl; Aydin, Murat; Edwards, Jon S.; Buizert, Christo; Brook, Edward J.; Epifanio, Jenna; Kahle, Emma; Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}], "date_created": "Sat, 02 Feb 2019 00:00:00 GMT", "description": "Gases trapped in ice cores have revealed astonishing things about the greenhouse gas composition of the past atmosphere, including the fact that carbon dioxide concentrations never rose above 300 parts per million during the last 800,000 years. This places today\u0027s concentration of 400 parts per million in stark contrast. Furthermore, these gas records show that natural sources of greenhouse gas such as oceans and ecosystems act as amplifiers of climate change by increasing emissions of gases during warmer periods. Such amplification is expected to occur in the future, adding to the human-produced gas burden. The South Pole ice core will build upon these prior findings by expanding the suite of gases to include, for the first time, those potent trace gases that both trapped heat and depleted ozone during the past 40,000 years. The present project on inert gases and methane in the South Pole ice core will improve the dating of this crucial record, to unprecedented precision, so that the relative timing of events can be used to learn about the mechanism of trace gas production and destruction, and consequent climate change amplification. Ultimately, this information will inform predictions of future atmospheric chemical cleansing mechanisms and climate in the context of our rapidly changing atmosphere. This award also engages young people in the excitement of discovery and polar research, helping to entrain the next generations of scientists and educators. Education of graduate students, a young researcher (Buizert), and training of technicians, will add to the nation?s human resource base. \u003cbr/\u003e \u003cbr/\u003eThis award funds the construction of the gas chronology for the South Pole 1500m ice core, using measured inert gases (d15N and d40Ar--Nitrogen and Argon isotope ratios, respectively) and methane in combination with a next-generation firn densification model that treats the stochastic nature of air trapping and the role of impurities on densification. The project addresses fundamental gaps in scientific understanding that limit the accuracy of gas chronologies, specifically a poor knowledge of the controls on ice-core d15N and the possible role of layering and impurities in firn densification. These gaps will be addressed by studying the gas enclosure process in modern firn at the deep core site. The work will comprise the first-ever firn air pumping experiment that has tightly co-located measurements of firn structural properties on the core taken from the same borehole.\u003cbr/\u003e\u003cbr/\u003eThe project will test the hypothesis that the lock-in horizon as defined by firn air d15N, CO2, and methane is structurally controlled by impermeable layers, which are in turn created by high-impurity content horizons in which densification is enhanced. Thermal signals will be sought using the inert gas measurements, which improve the temperature record with benefits to the firn densification modeling. Neon, argon, and oxygen will be measured in firn air and a limited number of deep core samples to test whether glacial period layering was enhanced, which could explain low observed d15N in the last glacial period. Drawing on separate volcanic and methane synchronization to well-dated ice cores to create independent ice and gas tie points, independent empirical estimates of the gas age-ice age difference will be made to check the validity of the firn densification model-inert gas approach to calculating the gas age-ice age difference. These points will also be used to test whether the anomalously low d15N seen during the last glacial period in east Antarctic ice cores is due to deep air convection in the firn, or a missing impurity dependence in the firn densification models. \u003cbr/\u003e\u003cbr/\u003eThe increased physical understanding gained from these studies, combined with new high-precision measurements, will lead to improved accuracy of the gas chronology of the South Pole ice core, which will enhance the overall science return from this gas-oriented core. This will lead to clarification of timing of atmospheric gas variations and temperature, and aid in efforts to understand the biogeochemical feedbacks among trace gases. These feedbacks bear on the future response of the Earth System to anthropogenic forcing. Ozone-depleting substances will be measured in the South Pole ice core record, and a precise gas chronology will add value. Lastly, by seeking a better understanding of the physics of gas entrapment, the project aims to have an impact on ice-core science in general.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "USAP-DC; AMD; LABORATORY; Antarctica; NITROGEN ISOTOPES; USA/NSF; METHANE; Amd/Us; FIELD INVESTIGATION", "locations": "Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Sowers, Todd A.; 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": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core", "uid": "p0010005", "west": 0.0}, {"awards": "0838855 Jacobel, Robert; 0838947 Tulaczyk, Slawek; 0839142 Tulaczyk, Slawek; 0838763 Anandakrishnan, Sridhar; 0838764 Anandakrishnan, Sridhar; 0839059 Powell, Ross; 0839107 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": "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": "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": "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": "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": "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": "601234", "doi": "10.15784/601234", "keywords": "ACL; Antarctica; Biomarker; BIT Index; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Stream; Whillans Ice Stream; WISSARD", "people": "Warny, Sophie; Baudoin, Patrick; Askin, Rosemary; Coenen, Jason; Casta\u00f1eda, Isla; Scherer, Reed Paul", "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": "000148", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS ID#s 201035, 201162, 201205", "url": "http://ds.iris.edu/"}, {"dataset_uid": "601245", "doi": "10.15784/601245", "keywords": "Antarctica; Pollen; West Antarctica; WISSARD", "people": "Coenen, Jason; Casta\u00f1eda, Isla; Scherer, Reed Paul; Askin, Rosemary; Warny, Sophie; Baudoin, Patrick", "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": "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": "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/"}], "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": "2023425 Schofield, Oscar; 1440435 Ducklow, Hugh", "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": "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": "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": "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": "601811", "doi": null, "keywords": "Antarctica; Bellingshausen Sea; Cryosphere; Southern Ocean", "people": "Desvignes, Thomas; Hilton, Eric; Steinberg, Deborah; Biesack, Ellen; Cheng, Chi-Hing; McDowell, Jan; Corso, Andrew", "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": "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": "Friedlaender, Ari; Boyer, Keyvi; Bierlich, KC; Nowacek, Douglas; Dale, Julian", "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"}, {"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": "001367", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1701"}, {"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": "200124", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1801", "url": "https://www.rvdata.us/search/cruise/LMG1801"}], "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\u00c3\u00a8lie 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).\u003cbr/\u003e\u003cbr/\u003eThe 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 Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "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": "1056396 Morgan-Kiss, Rachael", "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": "Genetic sequence identifier: Accession Numbers: GU132860-GU132939; JN091926-JN091960; JQ9243533-JQ924384; KJ848331-KJ848439; KU196097-KU196166; PRJNA396917", "datasets": [{"dataset_uid": "000241", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Genetic sequence identifier: Accession Numbers: GU132860-GU132939; JN091926-JN091960; JQ9243533-JQ924384; KJ848331-KJ848439; KU196097-KU196166; PRJNA396917", "url": "https://www.ncbi.nlm.nih.gov/genbank/"}], "date_created": "Mon, 26 Feb 2018 00:00:00 GMT", "description": "This CAREER proposal will support an early career female PI to establish an integrated research and education program in the fields of polar biology and environmental microbiology, focusing on single-celled eukaryotes (protists) in high latitude ice-covered Antarctic lakes systems. Protists play important roles in energy flow and material cycling, and act as both primary producers (fixing inorganic carbon by photosynthesis) and consumers (preying on bacteria by phagotrophic digestion). The McMurdo Dry Valleys (MDV) located in Victoria Land, Antarctica, harbor microbial communities which are isolated in the unique aquatic ecosystem of perennially ice-capped lakes. The lakes support exclusively microbial consortia in chemically stratified water columns that are not influenced by seasonal mixing, allochthonous inputs, or direct human impact. This project will exploit permanently stratified biogeochemistry that is unique across the water columns of several MDV lakes to address gaps in our understanding of protist trophic function in aquatic food webs. The proposed research will examine (1) the impact of permanent biogeochemical gradients on protist trophic strategy, (2) the effect of major abiotic drivers (light and nutrients) on the distribution of two key mixotrophic and photoautotrophic protist species, and (3) the effect of episodic nutrient pulses on mixotroph communities in high latitude (ultraoligotrophic) MDV lakes versus low latitude (eutrophic) watersheds. The project will impact the fields of microbial ecology and environmental microbiology by combining results from field, laboratory and in situ incubation studies to synthesize new models for the protist trophic roles in the aquatic food web. The research component of this proposed project will be tightly integrated with the development of two new education activities designed to exploit the inherent excitement associated with polar biological research. The educational objectives are: 1) to establish a teaching module in polar biology in a core undergraduate course for microbiology majors; 2) to develop an instructional module to engage middle school girls in STEM disciplines. Undergraduates and middle school girls will also work with a doctoral student on his experiments in local Ohio watersheds.", "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 Organisms and Ecosystems", "paleo_time": null, "persons": "Morgan-Kiss, Rachael", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": -90.0, "title": "CAREER:Protist Nutritional Strategies in Permanently Stratified Antarctic Lakes", "uid": "p0000310", "west": -180.0}, {"awards": "1425989 Sarmiento, Jorge", "bounds_geometry": "POLYGON((-180 -52.6153,-168.67689 -52.6153,-157.35378 -52.6153,-146.03067 -52.6153,-134.70756 -52.6153,-123.38445 -52.6153,-112.06134 -52.6153,-100.73823 -52.6153,-89.41512 -52.6153,-78.09201 -52.6153,-66.7689 -52.6153,-66.7689 -55.18958,-66.7689 -57.76386,-66.7689 -60.33814,-66.7689 -62.91242,-66.7689 -65.4867,-66.7689 -68.06098,-66.7689 -70.63526,-66.7689 -73.20954,-66.7689 -75.78382,-66.7689 -78.3581,-78.09201 -78.3581,-89.41512 -78.3581,-100.73823 -78.3581,-112.06134 -78.3581,-123.38445 -78.3581,-134.70756 -78.3581,-146.03067 -78.3581,-157.35378 -78.3581,-168.67689 -78.3581,180 -78.3581,178.62318 -78.3581,177.24636 -78.3581,175.86954 -78.3581,174.49272 -78.3581,173.1159 -78.3581,171.73908 -78.3581,170.36226 -78.3581,168.98544 -78.3581,167.60862 -78.3581,166.2318 -78.3581,166.2318 -75.78382,166.2318 -73.20954,166.2318 -70.63526,166.2318 -68.06098,166.2318 -65.4867,166.2318 -62.91242,166.2318 -60.33814,166.2318 -57.76386,166.2318 -55.18958,166.2318 -52.6153,167.60862 -52.6153,168.98544 -52.6153,170.36226 -52.6153,171.73908 -52.6153,173.1159 -52.6153,174.49272 -52.6153,175.86954 -52.6153,177.24636 -52.6153,178.62318 -52.6153,-180 -52.6153))", "dataset_titles": "Biogeochemical profiling float data from the Southern Ocean Carbon and Climate Observation and Modeling (SOCCOM) program.UCSD Research Data Collections DOI:10.6075/J09021PC; Expedition Data; Model output NOAA GFDL CM2_6 Cant Hant storage", "datasets": [{"dataset_uid": "001369", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "000208", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Biogeochemical profiling float data from the Southern Ocean Carbon and Climate Observation and Modeling (SOCCOM) program.UCSD Research Data Collections DOI:10.6075/J09021PC", "url": "http://library.ucsd.edu/dc/object/bb66239018"}, {"dataset_uid": "601144", "doi": "10.15784/601144", "keywords": "Antarctica; Anthropogenic Heat; Atmosphere; Carbon Storage; Climate Change; Eddy; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Heat Budget; Modeling; Model Output; Oceans; Paleoclimate; Snow/ice; Snow/Ice; Southern Ocean", "people": "Chen, Haidi", "repository": "USAP-DC", "science_program": null, "title": "Model output NOAA GFDL CM2_6 Cant Hant storage", "url": "https://www.usap-dc.org/view/dataset/601144"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) project seeks to drive a transformative shift in our understanding of the crucial role of the Southern Ocean in taking up anthropogenic carbon and heat, and resupplying nutrients from the abyss to the surface. An observational program will generate vast amounts of new biogeochemical data that will provide a greatly improved view of the dynamics and ecosystem responses of the Southern Ocean. A modeling component will apply these observations to enhancing understanding of the current ocean, reducing uncertainty in projections of future carbon and nutrient cycles and climate.\u003cbr/\u003e\u003cbr/\u003eBecause it serves as the primary gateway through which the intermediate, deep, and bottom waters of the ocean interact with the surface layers and thus the atmosphere, the Southern Ocean has a profound influence on the oceanic uptake of anthropogenic carbon and heat as well as nutrient resupply from the abyss to the surface. Yet it is the least observed and understood region of the world ocean. The oceanographic community is on the cusp of two major advances that have the potential to transform understanding of the Southern Ocean. The first is the development of new biogeochemical sensors mounted on autonomous profiling floats that allow sampling of ocean biogeochemistry and acidification in 3-dimensional space with a temporal resolution of five to ten days. The SOCCOM float program proposed will increase the average number of biogeochemical profiles measured per month in the Southern Ocean by ~10-30x. The second is that the climate modeling community now has the computational resources and physical understanding to develop fully coupled climate models that can represent crucial mesoscale processes in the Southern Ocean, as well as corresponding models that assimilate observations to produce a state estimate. Together with the observations, this new generation of models provides the tools to vastly improve understanding of Southern Ocean processes and the ability to quantitatively assess uptake of anthropogenic carbon and heat, as well as nutrient resupply, both today and into the future.\u003cbr/\u003e\u003cbr/\u003eIn order to take advantage of the above technological and modeling breakthroughs, SOCCOM will implement the following research programs:\u003cbr/\u003e* Theme 1: Observations. Scripps Institution of Oceanography will lead a field program to expand the number of Southern Ocean autonomous profiling floats and equip them with sensors to measure pH, nitrate, and oxygen. The University of Washington and Monterey Bay Aquarium Research Institute will design, build, and oversee deployment of the floats. Scripps will also develop a mesoscale eddying Southern Ocean state estimate that assimilates physical and biogeochemical data into the MIT ocean general circulation model.\u003cbr/\u003e* Theme 2: Modeling. University of Arizona and Princeton University, together with NOAA\u0027s Geophysical Fluid Dynamics Laboratory (GFDL), will use SOCCOM observations to develop data/model assessment metrics and next-generation model analysis and evaluation, with the goal of improving process level understanding and reducing the uncertainty in projections of our future climate.\u003cbr/\u003e\u003cbr/\u003eLed by Climate Central, an independent, non-profit journalism and research organization that promotes understanding of climate science, SOCCOM will collaborate with educators and media professionals to inform policymakers and the public about the challenges of climate change and its impacts on marine life in the context of the Southern Ocean. In addition, the integrated team of SOCCOM scientists and educators will:\u003cbr/\u003e* communicate data and results of the SOCCOM efforts quickly to the public through established data networks, publications, broadcast media, and a public portal;\u003cbr/\u003e* train a new generation of diverse ocean scientists, including undergraduate students, graduate students, and postdoctoral fellows versed in field techniques, data calibration, modeling, and communication of research to non-scientists;\u003cbr/\u003e* transfer new sensor technology and related software to autonomous instrument providers and manufacturers to ensure that they become widely useable.", "east": -66.7689, "geometry": "POINT(-130.26855 -65.4867)", "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": true, "keywords": "USAP-DC; R/V NBP; NBP1701; CLIMATE MODELS", "locations": null, "north": -52.6153, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Sarmiento, Jorge; Rynearson, Tatiana", "platforms": "OTHER \u003e MODELS \u003e CLIMATE MODELS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "PI website; R2R; USAP-DC", "science_programs": null, "south": -78.3581, "title": "Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM)", "uid": "p0000197", "west": 166.2318}, {"awards": "1443474 Jenkins, Bethany", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1608", "datasets": [{"dataset_uid": "002664", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1608", "url": "https://www.rvdata.us/search/cruise/NBP1608"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "This project focuses on an important group of photosynthetic algae in the Southern Ocean (SO), diatoms, and the roles associated bacterial communities play in modulating their growth. Diatom growth fuels the SO food web and balances atmospheric carbon dioxide by sequestering the carbon used for growth to the deep ocean on long time scales as cells sink below the surface. The diatom growth is limited by the available iron in the seawater, most of which is not freely available to the diatoms but instead is tightly bound to other compounds. The nature of these compounds and how phytoplankton acquire iron from them is critical to understanding productivity in this region and globally. The investigators will conduct experiments to characterize the relationship between diatoms, their associated bacteria, and iron in open ocean and inshore waters. Experiments will involve supplying nutrients at varying nutrient ratios to natural phytoplankton assemblages to determine how diatoms and their associated bacteria respond to different conditions. This will provide valuable data that can be used by climate and food web modelers and it will help us better understand the relationship between iron, a key nutrient in the ocean, and the organisms at the base of the food web that use iron for photosynthetic growth and carbon uptake. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project supports early career senior investigators and the training of graduate and undergraduate students as well as outreach activities with middle school Girl Scouts in Rhode Island, inner city middle and high school age girls in Virginia, and middle school girls in Florida.\u003cbr/\u003e\u003cbr/\u003eThe project combines trace metal biogeochemistry, phytoplankton cultivation, and molecular biology to address questions regarding the production of iron-binding compounds and the role of diatom-bacterial interactions in this iron-limited region. Iron is an essential micronutrient for marine phytoplankton. Phytoplankton growth in the SO is limited by a lack of sufficient iron, with important consequences for carbon cycling and climate in this high latitude regime. Some of the major outstanding questions in iron biogeochemistry relate to the organic compounds that bind \u003e99.9% of dissolved iron in surface oceans. The investigators\u0027 prior research in this region suggests that production of strong iron-binding compounds in the SO is linked to diatom blooms in waters with high nitrate to iron ratios. The sources of these compounds are unknown but the investigators hypothesize that they may be from bacteria, which are known to produce such compounds for their own use. The project will test three hypotheses concerning the production of these iron-binding compounds, limitations on the biological availability of iron even if present in high concentrations, and the roles of diatom-associated bacteria in these processes. Results from this project will provide fundamental information about the biogeochemical trigger, and biological sources and function, of natural strong iron-binding compound production in the SO, where iron plays a critical role in phytoplankton productivity, carbon cycling, and climate regulation.", "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; NBP1608", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jenkins, Bethany", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Investigating Iron-inding Ligands in Southern Ocean Diatom Communities: The Role of Diatom-Bacteria Associations", "uid": "p0000852", "west": null}, {"awards": "1543245 Rynearson, Tatiana", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP1701; NCBI Popset of 43 Southern Ocean diatom isolates, including accessions ON678208.1 - ON678250.1; Specific growth rate measurements for 43 Southern Ocean diatoms", "datasets": [{"dataset_uid": "601586", "doi": "10.15784/601586", "keywords": "Antarctica; Biota; NBP1701; Phytoplankton; R/v Nathaniel B. Palmer; Specific Growth Rate; Thermal Optimum Temperature", "people": "Bishop, Ian", "repository": "USAP-DC", "science_program": null, "title": "Specific growth rate measurements for 43 Southern Ocean diatoms", "url": "https://www.usap-dc.org/view/dataset/601586"}, {"dataset_uid": "200328", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "NCBI Popset of 43 Southern Ocean diatom isolates, including accessions ON678208.1 - ON678250.1", "url": "https://www.ncbi.nlm.nih.gov/popset/?term=2248543458"}, {"dataset_uid": "002661", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1701", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "001369", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1701"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "The research will examine how diatoms (an important group of plankton in the Southern Ocean) adapt to environmental change. Diatoms will be sampled from different regions of the Southern Ocean, including the Drake Passage, the Pacific Sector of the Southern Ocean and the Ross Sea and examined to determine the range of genetic variation among diatoms in these regions. Experiments on a range of diatoms will be conducted in home laboratories and will be aimed at measuring shifts in physiological capacities over many generations in response to directional changes in the environment (temperature and pH). The information on the genetic diversity of field populations combined with information on potential rates of adaptability and genome changes will provide insight into ways in which polar marine diatoms populations may respond to environmental changes that may occur in surface oceans in the future or may have occurred during past climate conditions. Such information allows better modeling of biogeochemical cycles in the ocean as well as improves our abilities to interpret records of past ocean conditions. The project will support a doctoral student and a postdoctoral researcher as well as several undergraduate students. These scientists will learn the fundamentals of experimental evolution, a skill set that is being sought in the fields of biology and oceanography. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting that will design and facilitate a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW). \u003cbr/\u003e\u003cbr/\u003eBoth physiological and genetic variation are key parameters for understanding evolutionary processes in phytoplankton but they are essentially unknown for Southern Ocean diatoms. The extent to which these two factors determine plasticity and adaptability in field populations and the interaction between them will influence how and whether cold-adapted diatoms can respond to changing environments. This project includes a combination of field work to identify genetic diversity within diatoms using molecular approaches and experiments in the lab to assess the range of physiological variation in contemporary populations of diatoms and evolution experiments in the lab to assess how the combination of genetic diversity and physiological variation influence the evolutionary potential of diatoms under a changing environment. This research will uncover general relationships between physiological variation, genetic diversity, and evolutionary potential that may apply across microbial taxa and geographical regions, substantially improving efforts to predict shifts in marine ecosystems. Results from this study can be integrated into developing models that incorporate evolution to predict ecosystem changes under future climate change scenarios.", "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": true, "keywords": "USAP-DC; NBP1701; R/V NBP; AMD; USA/NSF; Amd/Us; DIATOMS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rynearson, Tatiana; Bishop, Ian", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "NCBI; R2R; USAP-DC", "science_programs": null, "south": null, "title": "NSFGEO-NERC: Evolutionary Response of Southern Ocean Diatoms to Environmental Change", "uid": "p0000850", "west": null}, {"awards": "1142166 McConnell, Joseph", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "WAIS Divide Ice-Core Aerosol Records from 1300 to 3404 m", "datasets": [{"dataset_uid": "601008", "doi": "10.15784/601008", "keywords": "Aerosol; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "people": "McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice-Core Aerosol Records from 1300 to 3404 m", "url": "https://www.usap-dc.org/view/dataset/601008"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "McConnell/1142166\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to use unprecedented aerosol and continuous gas (methane, carbon monoxide) measurements of the deepest section of the West Antarctic Ice Sheet (WAIS) Divide ice core to investigate rapid climate changes in Antarctica during the ~60,000 year long Marine Isotope Stage 3 period of the late Pleistocene. These analyses, combined with others, will take advantage of the high snow accumulation of the WAIS Divide ice core to yield the highest time resolution glaciochemical and gas record of any deep Antarctic ice core for this time period. The research will expand already funded discrete gas measurements and extend currently funded continuous aerosol measurements on the WAIS Divide ice core from ~25,000 to ~60,000 years before present, spanning Heinrich events 3 to 6 and Antarctic Isotope Maximum (AIM, corresponding to the Northern Hemisphere Dansgaard-Oeschger) events 3 to 14. With other high resolution Greenland cores and lower resolution Antarctic cores, the combined record will yield new insights into worldwide climate dynamics and abrupt change. The intellectual merit of the work is that it will be used to address the science goals of the WAIS Divide project including the identification of dust and biomass burning tracers such as black carbon and carbon monoxide which reflect mid- and low-latitude climate and atmospheric circulation patterns, and fallout from these sources affects marine and terrestrial biogeochemical cycles. Similarly, sea salt and ocean productivity tracers reflect changes in sea ice extent, marine primary productivity, wind speeds above the ocean, and atmospheric circulation. Volcanic tracers address the relationship between northern, tropical, and southern climates as well as stability of the West Antarctic ice sheet and sea level change. When combined with other gas records from WAIS Divide, the records developed here will transform understanding of mid- and low-latitude drivers of Antarctic, Southern Hemisphere, and global climate rapid changes and the timing of such changes. The broader impacts of the work are that it will enhance infrastructure through expansion of continuous ice core analytical techniques, train students and support collaboration between two U.S. institutions (DRI and OSU). All data will be made available to the scientific community and the public and will include participation the WAIS Divide Outreach Program. Extensive graduate and undergraduate student involvement is planned. Student recruitment will be made from under-represented groups building on a long track record. Broad outreach will be achieved through collaborations with the global and radiative modeling communities, NESTA-related and other educational outreach efforts, and public lectures. This proposed project does not require field work in the Antarctic.", "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": "McConnell, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Collaborative Research: Investigating Upper Pleistocene Rapid Climate Change using Continuous, Ultra-High-Resolution Aerosol and Gas Measurements in the WAIS Divide Ice Core", "uid": "p0000287", "west": -112.1115}, {"awards": "1143619 Severinghaus, Jeffrey", "bounds_geometry": "POINT(-112.09 -79.47)", "dataset_titles": null, "datasets": null, "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "This award supports a project to extend the study of gases in ice cores to those gases whose small molecular diameters cause them to escape rapidly from ice samples (the so-called \"fugitive gases\"). The work will employ helium, neon, argon, and oxygen measurements in the WAIS Divide ice core to better understand the mechanism of the gas close-off fractionation that occurs while air bubbles are incorporated into ice. The intellectual merit of the proposed work is that corrections for this fractionation using neon (which is constant in the atmosphere) may ultimately enable the first ice core-based atmospheric oxygen and helium records. Neon may also illuminate the mechanistic link between local insolation and oxygen used for astronomical dating of ice cores. Helium measure-ments in the deepest ~100 m of the core will also shed light on the stratigraphic integrity of the basal ice, and serve as a probe of solid earth-ice interaction at the base of the West Antarctic ice sheet. Past atmospheric oxygen records, currently unavailable prior to 1989 CE, would reveal changes in the size of the terrestrial biosphere carbon pool that accompany climate variations and place constraints on the biogeochemical feedback response to future warming. An atmospheric helium-3/helium-4 record would test the hypothesis that the solar wind (which is highly enriched in helium-3) condensed directly into Earth?s atmosphere during the collapse of the geomagnetic field that occurred 41,000 years ago, known as the Laschamp Event. Fugitive-gas samples will be taken on-site immediately after recovery of the ice core by the PI and one postdoctoral scholar, under the umbrella of an existing project to support replicate coring and borehole deepening. This work will add value to the scientific return from field work activity with little additional cost to logistical resources. The broader impacts of the work on atmospheric oxygen are that it may increase understanding of how terrestrial carbon pools and atmospheric greenhouse gas sources will respond in a feedback sense to the coming warming. Long-term atmospheric oxygen trends are also of interest for understanding biogeochemical regulatory mechanisms and the impact of atmospheric evolution on life. Helium records have value in understanding the budget of this non-renewable gas and its implications for space weather and solar activity. The project will train one graduate student and one postdoctoral scholar. The fascination of linking solid earth, cryosphere, atmosphere, and space weather will help to entrain and excite young scientists and efforts to understand the Earth as a whole interlinked system will provide fuel to outreach efforts at all ages.", "east": -112.09, "geometry": "POINT(-112.09 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "WAIS Divide; Not provided; Tracers; FIELD INVESTIGATION; Past Biospheric Carbon Storage; LABORATORY; Fugitive Gases; Basal Processes; Neon; Helium; FIELD SURVEYS; Antarctica", "locations": "WAIS Divide; Antarctica", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "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": -79.47, "title": "Fugitive Gases (Helium, Neon, and Oxygen) in the WAIS Divide Ice Core as Tracers of Basal Processes and Past Biospheric Carbon Storage", "uid": "p0000441", "west": -112.09}, {"awards": "0944254 Smith, Walker; 0944165 McGillicuddy, Dennis", "bounds_geometry": "POLYGON((168 -65,168.2 -65,168.4 -65,168.6 -65,168.8 -65,169 -65,169.2 -65,169.4 -65,169.6 -65,169.8 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,169.8 -65,169.6 -65,169.4 -65,169.2 -65,169 -65,168.8 -65,168.6 -65,168.4 -65,168.2 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65))", "dataset_titles": "Data from expdition NBP1201; Expedition Data; Project data: Processes Regulating Iron Supply at the Mesoscale - Ross Sea", "datasets": [{"dataset_uid": "000155", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Project data: Processes Regulating Iron Supply at the Mesoscale - Ross Sea", "url": "http://www.bco-dmo.org/project/2155"}, {"dataset_uid": "001442", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1201"}, {"dataset_uid": "000156", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Data from expdition NBP1201", "url": "http://www.bco-dmo.org/deployment/506350"}], "date_created": "Wed, 08 Jul 2015 00:00:00 GMT", "description": "The Ross Sea continental shelf is one of the most productive areas in the Southern Ocean, and may comprise a significant, but unaccounted for, oceanic CO2 sink, largely driven by phytoplankton production. The processes that control the magnitude of primary production in this region are not well understood, but data suggest that iron limitation is a factor. Field observations and model simulations indicate four potential sources of dissolved iron to surface waters of the Ross Sea: (1) circumpolar deep water intruding from the shelf edge; (2) sediments on shallow banks and nearshore areas; (3) melting sea ice around the perimeter of the polynya; and (4) glacial meltwater from the Ross Ice Shelf. The principal investigators hypothesize that hydrodynamic transport via mesoscale currents, fronts, and eddies facilitate the supply of dissolved iron from these four sources to the surface waters of the Ross Sea polynya. These hypotheses will be tested through a combination of in situ observations and numerical modeling, complemented by satellite remote sensing. In situ observations will be obtained during a month-long cruise in the austral summer. The field data will be incorporated into model simulations, which allow quantification of the relative contributions of the various hypothesized iron supply mechanisms, and assessment of their impact on primary production. The research will provide new insights and a mechanistic understanding of the complex oceanographic phenomena that regulate iron supply, primary production, and biogeochemical cycling. The research will thus form the basis for predictions about how this system may change in a warming climate. The broader impacts include training of graduate and undergraduate students, international collaboration, and partnership with several ongoing outreach programs that address scientific research in the Southern Ocean. The research also will contribute to the goals of the international research programs ICED (Integrated Climate and Ecosystem Dynamics) and GEOTRACES (Biogeochemical cycling and trace elements in the marine environment).", "east": 170.0, "geometry": "POINT(169 -65)", "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 PROFILERS/SOUNDERS \u003e PROFILERS; 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 MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "R/V NBP; Not provided", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; McGillicuddy, Dennis", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "BCO-DMO", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -65.0, "title": "Collaborative Research: Impact of Mesoscale Processes on Iron Supply and Phytoplankton Dynamics in the Ross Sea", "uid": "p0000330", "west": 168.0}, {"awards": "0838970 Foreman, Christine", "bounds_geometry": "POINT(161.667 -77.117)", "dataset_titles": "The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica", "datasets": [{"dataset_uid": "600104", "doi": "10.15784/600104", "keywords": "Antarctica; Biota; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Microbiology", "people": "Foreman, Christine", "repository": "USAP-DC", "science_program": null, "title": "The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600104"}], "date_created": "Fri, 10 Oct 2014 00:00:00 GMT", "description": "Dissolved organic matter (DOM) comprises a significant pool of Earth\u0027s organic carbon that dwarfs the amount present in living aquatic organisms. The properties and reactivity of DOM are not well defined, and the evolution of autochthonous DOM from its precursor materials in freshwater has not been observed. Recent sampling of a supraglacial stream formed on the Cotton Glacier in the Transantarctic Mountains revealed DOM that more closely resembles an assemblage of recognizable precursor organic compounds, based upon its UV-VIS and fluorescence spectra. It is suggested that the DOM from this water evolved over time to resemble materials present in marine and many inland surface waters. The transient nature of the system i.e., it reforms seasonally, also prevents any accumulation of the refractory DOM present in most surface waters. Thus, the Cotton Glacier provides us with a unique environment to study the formation of DOM from precursor materials. An interdisciplinary team will study the biogeochemistry of this progenitor DOM and how microbes modify it. By focusing on the chemical composition of the DOM as it shifts from precursor material to the more humified fractions, the investigators will relate this transition to bioavailability, enzymatic activity, community composition and microbial growth efficiency. This project will support education at all levels, K-12, high school, undergraduate, graduate and post-doc and will increase participation by under-represented groups in science. Towards these goals, the investigators have established relationships with girls\u0027 schools and Native American programs. Additional outreach will be carried out in coordination with PolarTREC, PolarPalooza, and if possible, an Antarctic Artist and Writer.", "east": 161.667, "geometry": "POINT(161.667 -77.117)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.117, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Foreman, Christine", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.117, "title": "Collaborative Research: The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica", "uid": "p0000458", "west": 161.667}, {"awards": "0839075 Priscu, John; 0839093 McConnell, Joseph; 0839122 Saltzman, Eric", "bounds_geometry": "POINT(112.05 -79.28)", "dataset_titles": "Fluorescence spectroscopy data from the West Antarctic Ice Sheet (WAIS) Divide ice core, WDC06A; Holocene Black Carbon in Antarctica; Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core; Prokaryotic cell concentration record from the WAIS Divide ice core", "datasets": [{"dataset_uid": "601072", "doi": "10.15784/601072", "keywords": "Antarctica; Biota; Cell Counts; Glaciology; Microbiology; WAIS Divide; WAIS Divide Ice Core", "people": "Priscu, John; Santibanez, Pamela", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Prokaryotic cell concentration record from the WAIS Divide ice core", "url": "https://www.usap-dc.org/view/dataset/601072"}, {"dataset_uid": "601034", "doi": "10.15784/601034", "keywords": "Antarctica; Atmosphere; Black Carbon; Chemistry:ice; Chemistry:Ice; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "people": "Arienzo, Monica; McConnell, Joseph", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Holocene Black Carbon in Antarctica", "url": "https://www.usap-dc.org/view/dataset/601034"}, {"dataset_uid": "601006", "doi": "10.15784/601006", "keywords": "Antarctica; Fluorescence Spectroscopy; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; WAIS Divide; WAIS Divide Ice Core", "people": "Priscu, John; D\u0027Andrilli, Juliana", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Fluorescence spectroscopy data from the West Antarctic Ice Sheet (WAIS) Divide ice core, WDC06A", "url": "https://www.usap-dc.org/view/dataset/601006"}, {"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": "Fri, 30 May 2014 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 use the WAIS Divide deep core to investigate the Last Deglaciation at sub-annual resolution through an integrated set of chemical and biological analyses. The intellectual merit of the project is that these analyses, combined with others, will take advantage of the high snow accumulation WAIS Divide site yielding the highest time resolution glacio-biogeochemical and gas record of any deep Antarctic ice core. With other high resolution Greenland cores (GISP2 and GRIP) and lower resolution Antarctic cores, the combined record will yield new insights into worldwide climate dynamics and abrupt change. The proposed chemical, biological, and elemental tracer measurements will also be used to address all of the WAIS Divide science themes. The broader impacts of the project include education and outreach activities such as numerous presentations to local K-12 students; opportunities for student and teacher involvement in the laboratory work; a teacher training program in Earth sciences in the heavily minority Santa Ana, Compton, and Costa Mesa, California school districts; and development of high school curricula. Extensive graduate and undergraduate student involvement also is planned and will include one post doctoral associate, one graduate student, and undergraduate hourly involvement at DRI; a graduate student and undergraduates at University of California, Irvine (UCI); and a post doctoral fellow at MSU. Student recruitment will be made from underrepresented groups building on a long track record of involvement and will include the NSF funded California Alliance for Minority Participation (CAMP) and the Montana American Indian Research Opportunities (AIRO).\u003cbr/\u003e\u003cbr/\u003eThis award does not involve field work in Antarctica.", "east": 112.05, "geometry": "POINT(112.05 -79.28)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e CARBON ANALYZERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e WAS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e ICE CORE MELTER; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PHOTOMETERS \u003e SPECTROPHOTOMETERS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Bacteria Ice Core; LABORATORY; Ice Core; FIELD INVESTIGATION; West Antarctica; Not provided; Dissolved Organic Carbon", "locations": "West Antarctica", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Foreman, Christine; Skidmore, Mark; Saltzman, Eric; McConnell, Joseph; Priscu, John", "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": "WAIS Divide Ice Core", "south": -79.28, "title": "Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core", "uid": "p0000273", "west": 112.05}, {"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": "0838830 Cottrell, Matthew", "bounds_geometry": "POLYGON((-64.079666 -64.77966,-64.07576590000001 -64.77966,-64.0718658 -64.77966,-64.0679657 -64.77966,-64.0640656 -64.77966,-64.06016550000001 -64.77966,-64.0562654 -64.77966,-64.0523653 -64.77966,-64.04846520000001 -64.77966,-64.0445651 -64.77966,-64.040665 -64.77966,-64.040665 -64.78326100000001,-64.040665 -64.786862,-64.040665 -64.790463,-64.040665 -64.794064,-64.040665 -64.797665,-64.040665 -64.801266,-64.040665 -64.804867,-64.040665 -64.808468,-64.040665 -64.812069,-64.040665 -64.81567,-64.0445651 -64.81567,-64.04846520000001 -64.81567,-64.0523653 -64.81567,-64.0562654 -64.81567,-64.06016550000001 -64.81567,-64.0640656 -64.81567,-64.0679657 -64.81567,-64.0718658 -64.81567,-64.07576590000001 -64.81567,-64.079666 -64.81567,-64.079666 -64.812069,-64.079666 -64.808468,-64.079666 -64.804867,-64.079666 -64.801266,-64.079666 -64.797665,-64.079666 -64.794064,-64.079666 -64.790463,-64.079666 -64.786862,-64.079666 -64.78326100000001,-64.079666 -64.77966))", "dataset_titles": "Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem", "datasets": [{"dataset_uid": "600097", "doi": "10.15784/600097", "keywords": "Antarctic Peninsula; Biota; LTER Palmer Station; Microbiology; Oceans; Southern Ocean", "people": "Cottrell, Matthew; Kirchman, David", "repository": "USAP-DC", "science_program": null, "title": "Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem", "url": "https://www.usap-dc.org/view/dataset/600097"}], "date_created": "Mon, 16 Dec 2013 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/\u003eLight quality and availability are likely to change in polar ecosystems as ice coverage and thickness decrease. How microbes adjust to these and other changes will have huge impacts on the polar marine ecosystems. Little is known about photoheterotrophic prokaryotes, which are hypothesized to gain a metabolic advantage by harvesting light energy in addition to utilizing dissolved organic matter (DOM). Photoheterotrophy is not included in current models of carbon cycling and energy flow. This research will examine three questions: 1. Are photoheterotrophic microbes present and active in Antarctic waters in winter and summer? 2. Does community structure of photoheterotrophs shift between summer and winter? 3. Which microbial groups assimilate more DOM in light than in the dark? The research will test hypotheses about activity of photoheterotrophs in winter and in summer, shifts in community structure between light and dark seasons and the potentially unique impacts of photoheterotrophs on biogeochemical processes in the Antarctic. The project will directly support a graduate student, will positively impact the NSF REU program at the College of Marine and Earth Studies, and will include students from the nation?s oldest historical minority college. The results will be featured during weekly tours of Lewes facilities (about 1000 visitors per year) and during Coast Day, an annual open-house that attracts about 10,000 visitors.", "east": -64.040665, "geometry": "POINT(-64.0601655 -64.797665)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.77966, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cottrell, Matthew; David, Kirchman", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.81567, "title": "Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem", "uid": "p0000473", "west": -64.079666}, {"awards": "0739681 Murray, Alison; 0739698 Doran, Peter", "bounds_geometry": "POINT(161.931 -77.3885)", "dataset_titles": "Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "datasets": [{"dataset_uid": "600080", "doi": "10.15784/600080", "keywords": "Antarctica; Biota; Carbon-14; Chemistry:fluid; Chemistry:Fluid; Chemistry:ice; Chemistry:Ice; Dry Valleys; Geochronology; Ice Core Records; Lake Vida; Microbiology", "people": "Murray, Alison", "repository": "USAP-DC", "science_program": null, "title": "Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "url": "https://www.usap-dc.org/view/dataset/600080"}], "date_created": "Thu, 12 Dec 2013 00:00:00 GMT", "description": "Lake Vida is the largest lake of the McMurdo Dry Valleys, with an approximately 20 m ice cover overlaying a brine of unknown depth with at least 7 times seawater salinity and temperatures below -10 degrees C year-round. Samples of brine collected from ice above the main water body contain 1) the highest nitrous oxide levels of any natural water body on Earth, 2) unusual geochemistry including anomalously high ammonia and iron concentrations, 3) high microbial counts with an unusual proportion (99%) of ultramicrobacteria. The microbial community is unique even compared to other Dry Valley Lakes. The research proposes to enter, for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical and microbiological analyses. The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake\u0027s history. The research will be conducted by a multidisciplinary team that will uncover the biogeochemical processes associated with a non-photosynthetic microbial community isolated for a significant period of time. This research will address diversity, adaptive mechanisms and evolutionary processes in the context of the physical evolution of the environment of Lake Vida. Results will be widely disseminated through publications, presentations at national and international meetings, through the Subglacial Antarctic Lake Exploration (SALE) web site and the McMurdo LTER web site. The research will support three graduate students and three undergraduate research assistants. The results will be incorporated into a new undergraduate biogeosciences course at the University of Illinois at Chicago which has an extremely diverse student body, dominated by minorities.", "east": 161.931, "geometry": "POINT(161.931 -77.3885)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.3885, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Murray, Alison; Doran, Peter", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.3885, "title": "Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "uid": "p0000485", "west": 161.931}, {"awards": "0838850 Gooseff, Michael", "bounds_geometry": "POLYGON((162.32 -77.62,162.418 -77.62,162.516 -77.62,162.614 -77.62,162.712 -77.62,162.81 -77.62,162.90800000000002 -77.62,163.006 -77.62,163.104 -77.62,163.202 -77.62,163.3 -77.62,163.3 -77.631,163.3 -77.64200000000001,163.3 -77.653,163.3 -77.664,163.3 -77.67500000000001,163.3 -77.686,163.3 -77.697,163.3 -77.708,163.3 -77.71900000000001,163.3 -77.73,163.202 -77.73,163.104 -77.73,163.006 -77.73,162.90800000000002 -77.73,162.81 -77.73,162.712 -77.73,162.614 -77.73,162.516 -77.73,162.418 -77.73,162.32 -77.73,162.32 -77.71900000000001,162.32 -77.708,162.32 -77.697,162.32 -77.686,162.32 -77.67500000000001,162.32 -77.664,162.32 -77.653,162.32 -77.64200000000001,162.32 -77.631,162.32 -77.62))", "dataset_titles": "The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys", "datasets": [{"dataset_uid": "600100", "doi": "10.15784/600100", "keywords": "Antarctica; Critical Zone; Mps-1 Water Potential Sensor; Physical Properties; Soil Moisture; Soil Temperature", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/600100"}], "date_created": "Tue, 26 Nov 2013 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/\u003eTwo models have been proposed to describe controls over microbial biogeography. One model proposes that microbes are ubiquitously distributed across the global environment, and that environmental conditions select for taxa physiologically adapted to local physical conditions. An alternative model predicts that dispersal is the important limitation to the distribution of microorganisms and that spatial heterogeneity of microbial communities is a result of both dispersal and local environmental limitations. According to both models, spatial heterogeneity of microbial communities may be especially pronounced in extreme ecosystems where the environmental selection for organisms with suitable physiology is most strongly manifest. We propose that Antarctic terrestrial environments are ideal places to examine microbial biogeography for 3 reasons: 1) the pristine nature and remoteness of Antarctica minimizes the prevalence of exotic species dispersed through human vectors; 2) the extreme conditions of Antarctic environments provide a strong environmental filter which limits the establishment of non-indigenous taxa; and 3) extreme heterogeneity in the terrestrial environment provides natural gradients of soil conditions (temperature, water and nutrient availability). In the proposed research we will investigate the influence of snow on the composition and spatial distribution of soil microbial communities and linked biogeochemical cycling in the McMurdo Dry Valleys. We will conduct fieldwork at the landscape scale (repeated remote sensing to characterize snow distribution), at the valley and patch scales (quantify snow patch ablation, microbial communities and biogeochemical cycling in subnivian soils). We hypothesize that snow patches play an important role in structuring the spatial distribution of soil microbial communities and their associated ecosystem functioning because of the physical and hydrological influences that snow patches have on the soil environment. The research will contribute to greater public awareness of the importance of polar research to fundamental questions of biology, ecology and hydrology through direct linkages with International Antarctic Institute public outreach activities, including dissemination of web-based learning units on environmental science and microbiology, targeted as resources for secondary and post-secondary educators. Three graduate students, one postdoctoral scholar and multiple undergraduates will participate in the research activities.", "east": 163.3, "geometry": "POINT(162.81 -77.675)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.62, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gooseff, Michael N.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.73, "title": "Collaborative Research: The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys", "uid": "p0000489", "west": 162.32}, {"awards": "0948357 Measures, Christopher; 0948338 Mitchell, B. Gregory", "bounds_geometry": "POLYGON((-63 -60,-62 -60,-61 -60,-60 -60,-59 -60,-58 -60,-57 -60,-56 -60,-55 -60,-54 -60,-53 -60,-53 -60.45,-53 -60.9,-53 -61.35,-53 -61.8,-53 -62.25,-53 -62.7,-53 -63.15,-53 -63.6,-53 -64.05,-53 -64.5,-54 -64.5,-55 -64.5,-56 -64.5,-57 -64.5,-58 -64.5,-59 -64.5,-60 -64.5,-61 -64.5,-62 -64.5,-63 -64.5,-63 -64.05,-63 -63.6,-63 -63.15,-63 -62.7,-63 -62.25,-63 -61.8,-63 -61.35,-63 -60.9,-63 -60.45,-63 -60))", "dataset_titles": "Project: Blue Water Zone; Trace Metal data 2006 (ID3801); Trace Metals - 2004", "datasets": [{"dataset_uid": "000174", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Trace Metal data 2006 (ID3801)", "url": "https://www.bco-dmo.org/dataset/3801"}, {"dataset_uid": "000218", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Trace Metals - 2004", "url": "https://www.bco-dmo.org/dataset/3800"}, {"dataset_uid": "000173", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Project: Blue Water Zone", "url": "http://www.bco-dmo.org/project/2145"}], "date_created": "Fri, 22 Nov 2013 00:00:00 GMT", "description": "The ocean plays a critical role in sequestering CO2 by exporting fixed carbon to the deep ocean through the biological pump. There is a pressing need to understand the systematics of carbon export in the Southern Ocean in the context of global warming because of the sensitivity of this region to climate change, already manifested as significant temperature increases. Numerous studies have indicated that Fe supply is a primary control on phytoplankton biomass and productivity in the Southern Ocean. The results from previous cruises in Feb-Mar 2004 and Jul-Aug 2006 have revealed the major natural Fe fertilization from Fe-rich shelf waters to the Fe-limited high nutrient low chlorophyll (HNLC) Antarctic Circumpolar Current Surface Water (ASW) in the southern Drake Passage, producing a series of phytoplankton blooms. Remaining questions include: How is natural Fe transported to the euphotic zone through small-meso-large scale horizontal-vertical transport and mixing in different HNLC ACC areas? How does plankton community structure evolve in response to a natural Fe addition, how does Fe speciation respond to biogeochemical processes, and how is Fe recycled to determine the longevity of phytoplankton blooms? How does the export of POC evolve as a function of upwelling-mixing, Fe addition-recycling and bacteria-plankton structure? This synthesis proposal will address these fundamental questions using a unique dataset combining multiyear physical, Fe and biogeochemical data collected between 2004 and 2006 from 2 NSF-funded Fe fertilization experiment cruises and 3 Antarctic Marine Living Resource (AMLR) cruises in the southern Drake Passage and southwestern Scotia Sea through collaboration with scientists in the AMLR program and US Southern Ocean GLOBEC projects. All investigators involved in this study are engaged in graduate and undergraduate instruction, and mentoring of postdoctoral researchers. Each P.I. will incorporate key elements of the proposed syntheses in our lectures, problem sets and group projects. The project includes support to convene a 4-5 day international workshop on natural Fe fertilization at Woods Hole Oceanographic Institution. The workshop will include scientists from United Kingdom, France and Germany who have conducted natural Fe fertilization experiments, and Korea and China who are planning to conduct natural Fe fertilization experiments. The participation of graduate students and postdoctoral scholars will be especially encouraged. The results will be published in a Deep-Sea Research II special issue.", "east": -53.0, "geometry": "POINT(-58 -62.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mitchell, B.; Azam, Farooq; Barbeau, Katherine; Gille, Sarah; Holm-Hansen, Osmund; Measures, Christopher; Selph, Karen", "platforms": "Not provided", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -64.5, "title": "Collaborative Research: Modeling and synthesis study of a natural iron fertilization site in the Southern Drake Passage", "uid": "p0000071", "west": -63.0}, {"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": "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 Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "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": "0839039 Kustka, Adam", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1101; Processed CurrentMeter Data from the Adare Basin near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1101 ", "datasets": [{"dataset_uid": "002653", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1101", "url": "https://www.rvdata.us/search/cruise/NBP1101"}, {"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"}], "date_created": "Tue, 17 Jan 2012 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/\u003eAn interdisciplinary team of researchers will focus on describing the high productivity patchiness observed in phytoplankton blooms in the mid to late summer in the Ross Sea, Antarctica. Key hypotheses to be tested and extended are that intrusions of nutrient and micro nutrient (e.g. Fe) rich water masses of the Antarctic modified circumpolar deep water (CDW) up onto continental shelves act to control the biogeochemical response of a large area of the productive Ross Sea coastal region. It is believed that this enhanced productivity may be a significant contributing factor to the global carbon cycle. \u003cbr/\u003e\u003cbr/\u003eA novel sampling strategy to be used to test the above hypotheses will employ a remotely controlled deep (1000m) glider (AUV) to locate and map CDW in near real time measuring C (conductivity), T (temperature), D (pressure) and apparent optical properties, and which will serve to direct further ship-based sampling. \u003cbr/\u003e\u003cbr/\u003eThe adaptive coordination of a polar research vessel with an AUV additionally provides an opportunity to engage in formal and informal education and public outreach on issues in polar research.", "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 Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Kohut, Josh", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": null, "title": "Collaborate Research:Modified Circumpolar Deep Water Intrusions as an Iron Source to the Summer Ross Sea Ecosystem", "uid": "p0000843", "west": null}, {"awards": "0230497 Kiene, Ronald", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0409", "datasets": [{"dataset_uid": "001616", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0409"}, {"dataset_uid": "002640", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0409", "url": "https://www.rvdata.us/search/cruise/NBP0409"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world\u0027s highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. \u003cbr/\u003e\u003cbr/\u003eThis project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. \u003cbr/\u003e\u003cbr/\u003eBoth Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.", "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": "Kiene, Ronald", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica", "uid": "p0000832", "west": null}, {"awards": "0230499 Kieber, David", "bounds_geometry": "POLYGON((-179.99998 -43.58056,-143.999984 -43.58056,-107.999988 -43.58056,-71.999992 -43.58056,-35.999996 -43.58056,0 -43.58056,35.999996 -43.58056,71.999992 -43.58056,107.999988 -43.58056,143.999984 -43.58056,179.99998 -43.58056,179.99998 -46.971468,179.99998 -50.362376,179.99998 -53.753284,179.99998 -57.144192,179.99998 -60.5351,179.99998 -63.926008,179.99998 -67.316916,179.99998 -70.707824,179.99998 -74.098732,179.99998 -77.48964,143.999984 -77.48964,107.999988 -77.48964,71.999992 -77.48964,35.999996 -77.48964,0 -77.48964,-35.999996 -77.48964,-71.999992 -77.48964,-107.999988 -77.48964,-143.999984 -77.48964,-179.99998 -77.48964,-179.99998 -74.098732,-179.99998 -70.707824,-179.99998 -67.316916,-179.99998 -63.926008,-179.99998 -60.5351,-179.99998 -57.144192,-179.99998 -53.753284,-179.99998 -50.362376,-179.99998 -46.971468,-179.99998 -43.58056))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001616", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0409"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world\u0027s highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. \u003cbr/\u003e\u003cbr/\u003eThis project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. \u003cbr/\u003e\u003cbr/\u003eBoth Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.", "east": 179.99998, "geometry": "POINT(0 -89.999)", "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": -43.58056, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.48964, "title": "Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica", "uid": "p0000582", "west": -179.99998}, {"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": "0838866 Buesseler, Ken", "bounds_geometry": "POLYGON((-75 -62,-74 -62,-73 -62,-72 -62,-71 -62,-70 -62,-69 -62,-68 -62,-67 -62,-66 -62,-65 -62,-65 -62.8,-65 -63.6,-65 -64.4,-65 -65.2,-65 -66,-65 -66.8,-65 -67.6,-65 -68.4,-65 -69.2,-65 -70,-66 -70,-67 -70,-68 -70,-69 -70,-70 -70,-71 -70,-72 -70,-73 -70,-74 -70,-75 -70,-75 -69.2,-75 -68.4,-75 -67.6,-75 -66.8,-75 -66,-75 -65.2,-75 -64.4,-75 -63.6,-75 -62.8,-75 -62))", "dataset_titles": "data deposited with Palmer Long-Term Ecological Research (LTER) repository.", "datasets": [{"dataset_uid": "000215", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "data deposited with Palmer Long-Term Ecological Research (LTER) repository.", "url": "http://pal.lternet.edu/data/"}], "date_created": "Wed, 31 Aug 2011 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eBy using a tool-box of particle flux and characterization techniques appropriate to the study of particulate organic carbon fluxes out of the upper sunlit zone, WHOI researchers will attempt to evaluate the so called \u0027biological pump\u0027 term at the Palmer Long Term Ecological Research (PAL) site in the Western Antarctic Peninsula (WAP). The goal of these measurements is to describe the seasonal dynamics of production, export (sinking) and at-depth remineralization rates of organic matter produced in the Antarctic photic zone. This should lead to a better understanding of the biogeochemical controls on the carbon cycle in this difficult to access region. Additionally, how much of the newly fixed organic carbon is exported off the shelf, effectively driving an influx of atmospheric (including anthropogenic) CO2 to be sequestered into the deep ocean is not presently known. Comparison of prior time series sediment traps in the WAP seem to indicate smaller sinking C fluxes than other, as equally as productive Antarctic coastal regions, e.g. the Ross Sea. New observations and modeling activities will attempt to explain this discrepancy, and to account for the apparently inefficient particle export. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\"", "east": -65.0, "geometry": "POINT(-70 -66)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Buesseler, Ken; Valdes, James", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -70.0, "title": "WAPflux - New Tools to Study the Fate of Phytoplankton Production in the West Antarctic Peninsula", "uid": "p0000686", "west": -75.0}, {"awards": "0739780 Taylor, Kendrick", "bounds_geometry": "POINT(-112.117 -79.666)", "dataset_titles": "WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning", "datasets": [{"dataset_uid": "600142", "doi": "10.15784/600142", "keywords": "Antarctica; Atmosphere; Black Carbon; Chemistry:ice; Chemistry:Ice; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "people": "Taylor, Kendrick C.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning", "url": "https://www.usap-dc.org/view/dataset/600142"}], "date_created": "Thu, 28 Apr 2011 00:00:00 GMT", "description": "Edwards/0739780\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a 2,000-year high-temporal resolution record of biomass burning from the analysis of black carbon in the WAIS Divide bedrock ice core. Pilot data for the WAIS WD05A core demonstrates that we now have the ability to reconstruct this record with minimal impact on the amount of ice available for other projects. The intellectual merit of this project is that black carbon (BC) aerosols result solely from combustion and play a critical but poorly quantified role in global climate forcing and the carbon cycle. When incorporated into snow and ice, BC increases absorption of solar radiation making seasonal snow packs, mountain glaciers, polar ice sheets, and sea ice much more vulnerable to climate warming. BC emissions in the Southern Hemisphere are dominated by biomass burning in the tropical regions of Southern Africa, South America and South Asia. Biomass burning, which results from both climate and human activities, alters the atmospheric composition of greenhouse gases, aerosols and perturbs key biogeochemical cycles. A long-term record of biomass burning is needed to aid in the interpretation of ice core gas composition and will provide important information regarding human impacts on the environment and climate before instrumental records. The broader impacts of the project are that it represents a paradigm shift in our ability to reconstruct the history of fire from ice core records and to understand its impact on atmospheric chemistry and climate over millennial time scales. This type of data is especially needed to drive global circulation model simulations of black carbon aerosols, which have been found to be an important component of global warming and which may be perturbing the hydrologic cycle. The project will also employ undergraduate students and is committed to attracting underrepresented groups to the physical sciences. The project?s outreach component will be conducted as part of the WAIS project outreach program and will reach a wide audience.", "east": -112.117, "geometry": "POINT(-112.117 -79.666)", "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": "Ice Core Chemistry; Not provided; Gas Record; Ice Core; Gas Measurement; Ice Core Gas Composition; Antarctica; LABORATORY; Bedrock Ice Core; Ice Core Gas Records; Wais Project; Greenhouse Gas; Atmospheric Chemistry; FIELD INVESTIGATION; Black Carbon; Biomass Burning; WAIS Divide; FIELD SURVEYS; West Antarctica; Methane", "locations": "Antarctica; West Antarctica; WAIS Divide", "north": -79.666, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.; McConnell, Joseph; Mitchell, Logan E; Sowers, Todd A.; Taylor, Kendrick C.", "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": "WAIS Divide Ice Core", "south": -79.666, "title": "WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning", "uid": "p0000022", "west": -112.117}, {"awards": "0636730 Vernet, Maria", "bounds_geometry": "POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52))", "dataset_titles": "Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "datasets": [{"dataset_uid": "600068", "doi": "10.15784/600068", "keywords": "Antarctica; Biota; Chemistry:fluid; Chemistry:Fluid; Geochemistry; NBP0902; Oceans; Physical Oceanography; Sea Surface; Southern Ocean; Weddell Sea", "people": "Vernet, Maria", "repository": "USAP-DC", "science_program": null, "title": "Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/600068"}], "date_created": "Mon, 22 Nov 2010 00:00:00 GMT", "description": "Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions:1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children\u0027s books will participate in cruises to produce an account of the expedition and a daily interactive website.", "east": -40.0, "geometry": "POINT(-47.5 -58.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -52.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Vernet, Maria", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Collaborative Reseach: Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean.", "uid": "p0000532", "west": -55.0}, {"awards": "0636543 Murray, Alison; 0636440 Long, David; 0636723 Helly, John; 0636319 Shaw, Timothy", "bounds_geometry": "POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52))", "dataset_titles": "Antarctic Iceberg Tracking Database; Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean; Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "datasets": [{"dataset_uid": "600064", "doi": "10.15784/600064", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Oceans; Sea Ice; Sea Surface; Southern Ocean; Weddell Sea", "people": "Shaw, Tim; Twining, Benjamin", "repository": "USAP-DC", "science_program": null, "title": "Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/600064"}, {"dataset_uid": "000134", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Antarctic Iceberg Tracking Database", "url": "http://www.scp.byu.edu/data/iceberg/database1.html"}, {"dataset_uid": "600065", "doi": "10.15784/600065", "keywords": "Biota; Geochemistry; NBP0902; Oceans; Physical Oceanography; Sea Ice; Southern Ocean; Weddell Sea", "people": "Murray, Alison", "repository": "USAP-DC", "science_program": null, "title": "Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/600065"}, {"dataset_uid": "600067", "doi": "10.15784/600067", "keywords": "Antarctica; NBP0902; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "people": "Helly, John", "repository": "USAP-DC", "science_program": null, "title": "Free-Drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/600067"}], "date_created": "Mon, 22 Nov 2010 00:00:00 GMT", "description": "Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions:1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children\u0027s books will participate in cruises to produce an account of the expedition and a daily interactive website.", "east": -40.0, "geometry": "POINT(-47.5 -58.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -52.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Twining, Benjamin; Shaw, Tim; Long, David; Murray, Alison; Helly, John", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "PI website; USAP-DC", "science_programs": null, "south": -65.0, "title": "Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean", "uid": "p0000511", "west": -55.0}, {"awards": "0338090 Madin, Laurence; 0338290 Kremer, Patricia", "bounds_geometry": "POLYGON((-69.9083 -52.7624,-68.96368 -52.7624,-68.01906 -52.7624,-67.07444 -52.7624,-66.12982 -52.7624,-65.1852 -52.7624,-64.24058 -52.7624,-63.29596 -52.7624,-62.35134 -52.7624,-61.40672 -52.7624,-60.4621 -52.7624,-60.4621 -54.01423,-60.4621 -55.26606,-60.4621 -56.51789,-60.4621 -57.76972,-60.4621 -59.02155,-60.4621 -60.27338,-60.4621 -61.52521,-60.4621 -62.77704,-60.4621 -64.02887,-60.4621 -65.2807,-61.40672 -65.2807,-62.35134 -65.2807,-63.29596 -65.2807,-64.24058 -65.2807,-65.1852 -65.2807,-66.12982 -65.2807,-67.07444 -65.2807,-68.01906 -65.2807,-68.96368 -65.2807,-69.9083 -65.2807,-69.9083 -64.02887,-69.9083 -62.77704,-69.9083 -61.52521,-69.9083 -60.27338,-69.9083 -59.02155,-69.9083 -57.76972,-69.9083 -56.51789,-69.9083 -55.26606,-69.9083 -54.01423,-69.9083 -52.7624))", "dataset_titles": "Data at U.S. JGOFS Data System; Expedition Data", "datasets": [{"dataset_uid": "001565", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0414"}, {"dataset_uid": "000118", "doi": "", "keywords": null, "people": null, "repository": "JGOF", "science_program": null, "title": "Data at U.S. JGOFS Data System", "url": "http://usjgofs.whoi.edu/jg/dir/jgofs/"}, {"dataset_uid": "001573", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0602"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Salps are planktonic grazers that have a life history, feeding biology and population dynamic strikingly different from krill, copepods or other crustacean zooplankton. Salps can occur in very dense population blooms that cover large areas and have been shown to have major impacts due to the their grazing and the production of fast-sinking fecal pellets. Although commonly acknowledged as a major component of the Southern Ocean zooplankton community, often comparable in biomass and distribution to krill, salps have received relatively little attention. Although extensive sampling has documented the seasonal abundance of salps in the Southern Ocean, there is a paucity of data on important rates that determine population growth and the role of this species in grazing and vertical flux of particulates. This proposed study will include: measurements of respiration and excretion rates for solitary and aggregate salps of all sizes; measurements of ingestion rates, including experiments to determine the size or concentration of particulates that can reduce ingestion; and determination of growth rates of solitaries and aggregates. In addition to the various rate measurements, this study will include quantitative surveys of salp horizontal and vertical distribution to determine their biomass and spatial distribution, and to allow a regional assessment of their effects. Measurements of the physical characteristics of the water column and the quantity and quality of particulate food available for the salps at each location will also be made. Satellite imagery and information on sea-ice cover will be used to test hypotheses about conditions that result in high densities of salps. Results will be used to construct a model of salp population dynamics, and both experimental and modeling results will be interpreted within the context of the physical and nutritional conditions to which the salps are exposed. This integrated approach will provide a good basis for understanding the growth dynamics of salp blooms in the Southern Ocean. Two graduate students will be trained on this project, and cruise and research experience will be provided for two undergraduate students. A portion of a website allowing students to be a virtual participant in the research will be created to strengthen students\u0027 quantitative skills. Both PI\u0027s will participate in teacher-researcher workshops, and collaboration with a regional aquarium will be developed in support of public education.", "east": -60.4621, "geometry": "POINT(-65.1852 -59.02155)", "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": -52.7624, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kremer, Patricia; Madin, Larry; Halanych, Kenneth", "platforms": "Not provided; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "JGOF; R2R", "science_programs": null, "south": -65.2807, "title": "Collaborative Research: Salpa Thompsoni in the Southern Ocean: Bioenergetics, Population Dynamics and Biogeochemical Impact", "uid": "p0000227", "west": -69.9083}, {"awards": "0125818 Gargett, Ann", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0508", "datasets": [{"dataset_uid": "002610", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0508", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in 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; 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 PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP; B-15J", "locations": "B-15J", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive effects of UV and vertical mixing on phytoplankton and bacterioplankton in the Ross Sea", "uid": "p0000822", "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": "0338097 DiTullio, Giacomo; 0127037 Neale, Patrick; 0338350 Dunbar, Robert; 0741411 Hutchins, David; 0338157 Smith, Walker", "bounds_geometry": "POLYGON((173.31833 -46.5719,173.757539 -46.5719,174.196748 -46.5719,174.635957 -46.5719,175.075166 -46.5719,175.514375 -46.5719,175.953584 -46.5719,176.392793 -46.5719,176.832002 -46.5719,177.271211 -46.5719,177.71042 -46.5719,177.71042 -48.759516,177.71042 -50.947132,177.71042 -53.134748,177.71042 -55.322364,177.71042 -57.50998,177.71042 -59.697596,177.71042 -61.885212,177.71042 -64.072828,177.71042 -66.260444,177.71042 -68.44806,177.271211 -68.44806,176.832002 -68.44806,176.392793 -68.44806,175.953584 -68.44806,175.514375 -68.44806,175.075166 -68.44806,174.635957 -68.44806,174.196748 -68.44806,173.757539 -68.44806,173.31833 -68.44806,173.31833 -66.260444,173.31833 -64.072828,173.31833 -61.885212,173.31833 -59.697596,173.31833 -57.50998,173.31833 -55.322364,173.31833 -53.134748,173.31833 -50.947132,173.31833 -48.759516,173.31833 -46.5719))", "dataset_titles": "Expedition Data; Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea; Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "datasets": [{"dataset_uid": "001687", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0305"}, {"dataset_uid": "001545", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0608"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "601340", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Geochemistry; NBP0601; Niskin Bottle; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Water Measurements", "people": "Smith, Walker; DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "url": "https://www.usap-dc.org/view/dataset/601340"}, {"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "600036", "doi": "10.15784/600036", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; Diatom; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600036"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "east": 177.71042, "geometry": "POINT(175.514375 -57.50998)", "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 PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF", "is_usap_dc": true, "keywords": "B-15J; OCEAN PLATFORMS; FIELD SURVEYS; R/V NBP", "locations": "B-15J", "north": -46.5719, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo; Smith, Walker; Dryer, Jennifer; Neale, Patrick", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; WATER-BASED PLATFORMS \u003e FIXED PLATFORMS \u003e SURFACE \u003e OCEAN PLATFORMS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.44806, "title": "Collaborative Research: Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000540", "west": 173.31833}, {"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": "0636773 DeMaster, David; 0636806 Smith, Craig", "bounds_geometry": "POLYGON((-71.2358 -52.7603,-69.75336 -52.7603,-68.27092 -52.7603,-66.78848 -52.7603,-65.30604 -52.7603,-63.8236 -52.7603,-62.34116 -52.7603,-60.85872 -52.7603,-59.37628 -52.7603,-57.89384 -52.7603,-56.4114 -52.7603,-56.4114 -54.29969,-56.4114 -55.83908,-56.4114 -57.37847,-56.4114 -58.91786,-56.4114 -60.45725,-56.4114 -61.99664,-56.4114 -63.53603,-56.4114 -65.07542,-56.4114 -66.61481,-56.4114 -68.1542,-57.89384 -68.1542,-59.37628 -68.1542,-60.85872 -68.1542,-62.34116 -68.1542,-63.8236 -68.1542,-65.30604 -68.1542,-66.78848 -68.1542,-68.27092 -68.1542,-69.75336 -68.1542,-71.2358 -68.1542,-71.2358 -66.61481,-71.2358 -65.07542,-71.2358 -63.53603,-71.2358 -61.99664,-71.2358 -60.45725,-71.2358 -58.91786,-71.2358 -57.37847,-71.2358 -55.83908,-71.2358 -54.29969,-71.2358 -52.7603))", "dataset_titles": "Expedition Data; Expedition data of LMG0802; Expedition data of LMG0902; Expedition Data of LMG0902; Expedition data of NBP0808; Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf; Species List, Species Abundance, and Sediment Geochemistry processed data acquired during Laurence M. Gould expedition LMG0802", "datasets": [{"dataset_uid": "002611", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0808", "url": "https://www.rvdata.us/search/cruise/NBP0808"}, {"dataset_uid": "002725", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0802", "url": "https://www.rvdata.us/search/cruise/LMG0802"}, {"dataset_uid": "601319", "doi": "10.15784/601319", "keywords": "Antarctica; Antarctic Peninsula; Biota; Bioturbation Coefficients; Diagenesis; Labile Organic Carbon; LOC Mean Residence Times; Marguerite Bay; Oceans; Organic Carbon Degradation Rates; Sediment Core", "people": "Isla, Enrique; Smith, Craig; DeMaster, David; Taylor, Richard; Thomas, Carrie", "repository": "USAP-DC", "science_program": null, "title": "Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf", "url": "https://www.usap-dc.org/view/dataset/601319"}, {"dataset_uid": "601303", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; Chlorophyll Concentration; LMG0802; Marcofauna; Megafauna; Oceans; R/v Laurence M. Gould; Seafloor Sampling; Species Abundance", "people": "Smith, Craig; DeMaster, David", "repository": "USAP-DC", "science_program": null, "title": "Species List, Species Abundance, and Sediment Geochemistry processed data acquired during Laurence M. Gould expedition LMG0802", "url": "https://www.usap-dc.org/view/dataset/601303"}, {"dataset_uid": "001486", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}, {"dataset_uid": "001513", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0802"}, {"dataset_uid": "002669", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}, {"dataset_uid": "002727", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0902", "url": "https://www.rvdata.us/search/cruise/LMG0902"}, {"dataset_uid": "002726", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0802", "url": "https://www.rvdata.us/search/cruise/LMG0802"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The Antarctic Peninsula region exhibits one of the largest warming trends in the world. Climate change in this region will reduce the duration of winter sea-ice cover, altering both the pelagic ecosystem and bentho-pelagic coupling. We postulate that shelf benthic ecosystems are highly suitable for tracking climate change because they act as \"low-pass\" filters, removing high-frequency seasonal noise and responding to longer-term trends in pelagic ecosystem structure and export production. We propose to conduct a 3-year study of bentho-pelagic coupling along a latitudinal climate gradient on the Antarctic Peninsula to explore the potential impacts of climate change (e.g., reduction in sea-ice duration) on Antarctic shelf ecosystems. We will conduct three cruises during summer and winter regimes along a 5- station transect from Smith Island to Marguerite Bay, evaluating a broad range of benthic ecological and biogeochemical processes. Specifically, we will examine the feeding strategies of benthic deposit feeders along this climatic gradient to elucidate the potential response of this major trophic group to climatic warming. In addition, we will (1) quantify carbon and nitrogen cycling and burial at the seafloor and (2) document changes in megafaunal, macrofaunal, and microbial community structure along this latitudinal gradient. We expect to develop predictive insights into the response of Antarctic shelf ecosystems to some of the effects of climate warming (e.g., a reduction in winter sea-ice duration). The proposed research will considerably broaden the ecological and carbon-flux measurements made as parts of the Palmer Station LTER and GLOBEC programs by providing a complementary benthic component. This project also will promote science education from the 9th grade to graduate-student levels. We will partner with the NSF-sponsored Southeastern Center for Ocean Science Education Excellence to reach students of all races in all areas of NC, SC and GA. The project will also benefit students at the post secondary level by supporting three graduate and two undergraduate students. During each of the three field excursions, NCSU and UH students will travel to Chile and Antarctica to participate in scientific research. Lastly, all three PIs will incorporate material from this project into their undergraduate and graduate courses.", "east": -56.4114, "geometry": "POINT(-63.8236 -60.45725)", "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; 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 PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS", "is_usap_dc": false, "keywords": "LMG0802; R/V LMG; AMD; Amd/Us; LMG0902; USA/NSF; NBP0808; USAP-DC; R/V NBP", "locations": null, "north": -52.7603, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "DeMaster, David; Smith, Craig", "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; USAP-DC", "science_programs": null, "south": -68.1542, "title": "Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling", "uid": "p0000552", "west": -71.2358}, {"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": "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": "601333", "doi": null, "keywords": "Antarctica; Flourometer; Mooring; NBP0601A; Ross Sea; Southern Ocean", "people": "Smith, Walker; Asper, Vernon", "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": "Asper, Vernon; Smith, Walker", "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": "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": "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": "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": "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": "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": "9530398 Anderson, Robert; 9530382 Smith, Walker; 9896290 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": "002138", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9708"}, {"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": "001874", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9802"}], "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": "0338164 Sedwick, Peter", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0601", "datasets": [{"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "002619", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601", "url": "https://www.rvdata.us/search/cruise/NBP0601"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "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; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive Effects of Iron, Light and CO2 on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000831", "west": null}, {"awards": "0440478 Tang, Kam", "bounds_geometry": "POINT(166.66267 -77.85067)", "dataset_titles": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "datasets": [{"dataset_uid": "600043", "doi": "10.15784/600043", "keywords": "Biota; McMurdo Sound; Oceans; Phytoplankton; Ross Sea; Southern Ocean; Zooplankton", "people": "Smith, Walker; Tang, Kam", "repository": "USAP-DC", "science_program": null, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "url": "https://www.usap-dc.org/view/dataset/600043"}], "date_created": "Mon, 04 May 2009 00:00:00 GMT", "description": "Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:\u003cbr/\u003eo Do P. Antarctica solitary cells and colonies differ in growth, composition and\u003cbr/\u003ephotosynthetic rates?\u003cbr/\u003eo How do nutrients and grazers affect colony development and size distribution of P. \u003cbr/\u003eAntarctica?\u003cbr/\u003eo How do nutrients and grazers act synergistically to affect the long-term population\u003cbr/\u003edynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience.", "east": 166.66267, "geometry": "POINT(166.66267 -77.85067)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.85067, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Tang, Kam; Smith, Walker", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.85067, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial forms of Phaeocystis antarctica", "uid": "p0000214", "west": 166.66267}, {"awards": "0338342 Foreman, Christine; 0338260 Chin, Yu-Ping", "bounds_geometry": "POINT(166.167 -77.55)", "dataset_titles": "Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "datasets": [{"dataset_uid": "600168", "doi": "10.15784/600168", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Critical Zone; Ross Island; Sample/collection Description; Sample/Collection Description; Water Samples", "people": "Foreman, Christine; Chin, Yu-Ping", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "url": "https://www.usap-dc.org/view/dataset/600168"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "Dissolved organic matter (DOM) is a significant chemical component in aquatic systems because it acts as an important carbon source for microorganisms, absorbs harmful radiation in sunlight, is able to complex metals, and can participate in important biogeochemical reactions. This study will investigate the biogeochemical cycling of DOM in a small coastal Antarctic pond, Pony Lake, located on Cape Royds, Ross Island. Because there are no higher plants present at this site all of the DOM in this lake is derived from microorganisms. Thus, Pony Lake is an ideal site to study the effect of physical, chemical, and microbial processes on the composition and character of the DOM pool. Finally, Pony Lake is also an ideal site to collect an International Humic Substances Society (IHSS) fulvic acid standard. Unlike other IHSS standards, this standard will not contain DOM components derived from higher land plants. To better understand the role of physical influences, the project will study the changes in the DOM pool as the lake evolves from ice-covered to ice-free conditions during the summer, as well as the relationship of DOM to the observed turnover of dominant microbial communities in the lake. Scientists will also monitor changes in microbial abundance, diversity, and productivity that may occur during the ice to open-water transition period. This research will provide much needed information regarding the relationship between microbial diversity and DOM biogeochemistry. Middle school science students will be active participants in this project through the Internet, while scientists are in the field, and in the lab.", "east": 166.167, "geometry": "POINT(166.167 -77.55)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; FIELD SURVEYS", "locations": null, "north": -77.55, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Foreman, Christine; Chin, Yu-Ping", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.55, "title": "Collaborative Research: Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "uid": "p0000548", "west": 166.167}, {"awards": "0742057 Gallager, Scott", "bounds_geometry": "POLYGON((-168.291 -64.846,-165.018 -64.846,-161.745 -64.846,-158.472 -64.846,-155.199 -64.846,-151.926 -64.846,-148.653 -64.846,-145.38 -64.846,-142.107 -64.846,-138.834 -64.846,-135.561 -64.846,-135.561 -66.0269,-135.561 -67.2078,-135.561 -68.3887,-135.561 -69.5696,-135.561 -70.7505,-135.561 -71.9314,-135.561 -73.1123,-135.561 -74.2932,-135.561 -75.4741,-135.561 -76.655,-138.834 -76.655,-142.107 -76.655,-145.38 -76.655,-148.653 -76.655,-151.926 -76.655,-155.199 -76.655,-158.472 -76.655,-161.745 -76.655,-165.018 -76.655,-168.291 -76.655,-168.291 -75.4741,-168.291 -74.2932,-168.291 -73.1123,-168.291 -71.9314,-168.291 -70.7505,-168.291 -69.5696,-168.291 -68.3887,-168.291 -67.2078,-168.291 -66.0269,-168.291 -64.846))", "dataset_titles": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "datasets": [{"dataset_uid": "600086", "doi": "10.15784/600086", "keywords": "Amundsen Sea; Biota; Microbiology; Navigation; Oceans; Oden; OSO2007; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Dennett, Mark; Gallager, Scott", "repository": "USAP-DC", "science_program": null, "title": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "url": "https://www.usap-dc.org/view/dataset/600086"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe research will continue and extend the study in the Southern Ocean that was initiated during the Oden Southern Ocean 2006 expedition in collaboration with Swedish scientist Mellissa Chierici. We will quantify carbon flux through the food web in the marginal ice zone (MIZ) by measuring size fractionated primary and secondary production, grazing and carbon flux through nanoplankton (2-20 um), microplankton (20-200um), and mesoplankton (200-2000 um). Community structure, species abundance and size specific grazing rates will be quantified using a variety of techniques both underway and at ice stations along the MIZ. The proposed cruise track extends across the Drake Passage to the Western Antarctic Peninsula (WAP) with three station transects along a gradient from the open ocean through the marginal ice zone (MIZ) in the Bellinghausen and Amundsen Seas and into the Ross Sea Polynya. Ice stations along each transect will provide material to characterize production associated with annual ice. Underway measurements of primary and secondary production (chlorophyll, CDOM, microplankton, and mesoplankton) and hydrography (temperature, salinity, pH, DO, turbidity) will establish a baseline for future cruises and as support for other projects such as biogeochemical studies on carbon dioxide drawdown and trace metal work on primary production. The outcome of these measurements will be a description of nano to mesoplankton standing stocks, community structure, and carbon flux along the MIZ in the Bellinghausen and Amundsen Seas and the Ross Sea Polynya.", "east": -135.561, "geometry": "POINT(-151.926 -70.7505)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.846, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gallager, Scott; Dennett, Mark", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.655, "title": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "uid": "p0000563", "west": -168.291}, {"awards": "0741403 Sherrell, Robert", "bounds_geometry": "POLYGON((-180 -69,-172.5 -69,-165 -69,-157.5 -69,-150 -69,-142.5 -69,-135 -69,-127.5 -69,-120 -69,-112.5 -69,-105 -69,-105 -69.9,-105 -70.8,-105 -71.7,-105 -72.6,-105 -73.5,-105 -74.4,-105 -75.3,-105 -76.2,-105 -77.1,-105 -78,-112.5 -78,-120 -78,-127.5 -78,-135 -78,-142.5 -78,-150 -78,-157.5 -78,-165 -78,-172.5 -78,180 -78,178.8 -78,177.6 -78,176.4 -78,175.2 -78,174 -78,172.8 -78,171.6 -78,170.4 -78,169.2 -78,168 -78,168 -77.1,168 -76.2,168 -75.3,168 -74.4,168 -73.5,168 -72.6,168 -71.7,168 -70.8,168 -69.9,168 -69,169.2 -69,170.4 -69,171.6 -69,172.8 -69,174 -69,175.2 -69,176.4 -69,177.6 -69,178.8 -69,-180 -69))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 10 Mar 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe research objective is (1) to determine the distributions and dynamics of a full suite of bioactive trace metals in dissolved and suspended particulate forms, along sampling transects of the Amundsen and Ross Seas. And (2) to test the sensitivity of overall cellular metal stoichiometry (metal/carbon ratios) to natural gradients in species assemblage and Fe availability. Our earlier findings from a single Ross Sea station and from a Drake Passage crossing suggest that Fe-limited phytoplankton cells are unusually enriched in Zn, Cu and Cd relative to biomass carbon, with strong implications for the biogeochemical cycling of these elements relative to carbon fluxes in the Southern Ocean. In collaboration with other researchers on the cruise, we will also measure metal stoichiometry of cells exposed to predicted 2010 temperature and carbon dioxide levels in shipboard incubation studies, as a window into possible effects of climate change on metals biogeochemistry in these regions. This proposal will support close international collaborations and lasting infrastructure development as US and Swedish scientists, and more importantly, their students, work toward shared the shared goal of understanding a region that is experiencing one of the fastest rates of climate change on the globe. Trace metal micro-nutrients are a key control on the productivity of Antarctic marine ecosystems. Our results will be made widely available through research publications and internet-available databases, and public outreach through COSEE at Rutgers University.", "east": -105.0, "geometry": "POINT(-148.5 -73.5)", "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": "Sherrell, Robert", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden: Bioactive trace metals in the Amundsen and Ross Seas", "uid": "p0000561", "west": 168.0}, {"awards": "0234249 Hollibaugh, James", "bounds_geometry": "POLYGON((-73 -64,-72.1 -64,-71.2 -64,-70.3 -64,-69.4 -64,-68.5 -64,-67.6 -64,-66.7 -64,-65.8 -64,-64.9 -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,-64.9 -68,-65.8 -68,-66.7 -68,-67.6 -68,-68.5 -68,-69.4 -68,-70.3 -68,-71.2 -68,-72.1 -68,-73 -68,-73 -67.6,-73 -67.2,-73 -66.8,-73 -66.4,-73 -66,-73 -65.6,-73 -65.2,-73 -64.8,-73 -64.4,-73 -64))", "dataset_titles": "Ammonia Oxidizing Bacteria and Archaea Abundance", "datasets": [{"dataset_uid": "000117", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "Ammonia Oxidizing Bacteria and Archaea Abundance", "url": "http://oceaninformatics.ucsd.edu/datazoo/data/pallter/datasets?action=summary\u0026id=114"}], "date_created": "Mon, 01 Dec 2008 00:00:00 GMT", "description": "This project will investigate the distribution, phylogenetic affinities and ecological aspects of ammonium-oxidizing bacteria in the Palmer Long-Term Ecological Research study area. Ammonia oxidation is the first step in the conversion of regenerated nitrogen to dinitrogen gas via denitrification, a 3-step pathway mediated by three distinct guilds of bacteria. As such, ammonia oxidation is important to the global nitrogen cycle. Ammonia oxidation and the overall process of nitrification-denitrification have received little attention in polar oceans where it is significant and where the effects of climate change on biogeochemical rates are likely to be pronounced. The goals of the studies proposed here are A) to obtain more conclusive information concerning composition of Antarctic ammonia oxidizers; B) to begin characterizing their ecophysiology and ecology; and C) to obtain cultures of the organism for more detailed studies. Water column and sea ice AOB assemblages will be characterized phylogenetically and the different kinds of AOB in various samples will be quantified. Nitrification rates will be measured across the LTER study area in water column, sea ice and sediment samples. Grazing rates on AOB will be determined and their sensitivity to UV light evaluated. In addition, the significance of urea nitrogen as a source of reduced nitrogen to AOB will be assessed and the temperature response of nitrification over temperature ranges appropriate to polar regions will be evaluated. This work will provide insights into the ecology of AOB and the knowledge needed to model how water column nitrification will respond to changes in the polar ecosystems accompanying global climate change.", "east": -64.0, "geometry": "POINT(-68.5 -66)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hollibaugh, James T.", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -68.0, "title": "Distribution And Ecology Of Ammonia Oxidizing Bacteria In The Palmer LTER Study Area", "uid": "p0000225", "west": -73.0}, {"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": "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": "Saltzman, Eric; Aydin, Murat", "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": "Aydin, Murat; Williams, Margaret; Saltzman, Eric", "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"}, {"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": "Aydin, Murat; Saltzman, Eric", "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": "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"}], "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": "0338267 Gooseff, Michael", "bounds_geometry": "POLYGON((161.6 -77.4,161.773 -77.4,161.946 -77.4,162.119 -77.4,162.292 -77.4,162.465 -77.4,162.638 -77.4,162.811 -77.4,162.984 -77.4,163.157 -77.4,163.33 -77.4,163.33 -77.435,163.33 -77.47,163.33 -77.505,163.33 -77.54,163.33 -77.575,163.33 -77.61,163.33 -77.645,163.33 -77.68,163.33 -77.715,163.33 -77.75,163.157 -77.75,162.984 -77.75,162.811 -77.75,162.638 -77.75,162.465 -77.75,162.292 -77.75,162.119 -77.75,161.946 -77.75,161.773 -77.75,161.6 -77.75,161.6 -77.715,161.6 -77.68,161.6 -77.645,161.6 -77.61,161.6 -77.575,161.6 -77.54,161.6 -77.505,161.6 -77.47,161.6 -77.435,161.6 -77.4))", "dataset_titles": "Antarctic Hydrologic Margin Microbiology and Biogeochemistry - data; Hydrologic Margins Research Project, 2004-2008, McMurdo Dry Valleys", "datasets": [{"dataset_uid": "000238", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Antarctic Hydrologic Margin Microbiology and Biogeochemistry - data", "url": "http://water.engr.psu.edu/gooseff/web_antarctica/data.html"}, {"dataset_uid": "600016", "doi": "", "keywords": null, "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Hydrologic Margins Research Project, 2004-2008, McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/600016"}], "date_created": "Thu, 11 Sep 2008 00:00:00 GMT", "description": "Aquatic-terrestrial transition zones are crucial environments in understanding the biogeochemistry of landscapes. In temperate watersheds, these areas are generally dominated by riparian zones, which have been identified as regions of special interest for biogeochemistry because of the increased microbial activity in these locations, and because of the importance of these hydrological margins in facilitating and buffering hydrologic and biogeochemical exchanges between terrestrial and aquatic ecosystems. In the Antarctic Dry Valleys, terrestrial-aquatic transition zones are intriguing landscape features because of the vast importance of water in this polar desert, and because the material and energy budgets of dry valley ecosystems are linked by hydrology. Hydrological margins in aquatic-terrestrial transition zones will be studied in the Dry Valleys of Antarctica to answer two overarching questions: (1) what are the major controls over hydrologic and biogeochemical exchange across aquaticterrestrial transition zones and (2) to what extent do trends in nutrient cycling (e.g. nitrogen cycling) across these transition zones reflect differences in microbial communities or function vs. differences in the physical and chemical environment (e.g., redox potential)? The hydrologic gradients that define these interfaces provide the opportunity to assess the relative influence of physical conditions and microbial biodiversity and functioning upon biogeochemical cycling. Coordinated hydrologic, biogeochemical, and molecular microbial studies will be executed within hydrologic margins with the following research objectives: to determine the role of sediment characteristics, permafrost and active layer dynamics, and topography on sub-surface water content and distribution in hydrologic margins, to determine the extent to which transformations of nitrogen in hydrological margins are influenced by physical conditions (i.e., moisture, redox potential and pH) or by the presence of specific microbial communities (e.g., denitrifiers), and to characterize the microbial community structure and function of saturated zones.\u003cbr/\u003e\u003cbr/\u003eThis proposed research will provide an improved understanding of the interaction of liquid water, soils, microbial communities, and biogeochemistry within the important hydrologic margin landscape units of the dry valleys. Dry valleys streams and lakes are unique because there is no influence of higher vegetation on the movement of water and may therefore provide a model system for understanding physical and hydrological influences on microbial ecology and biogeochemistry. Hence the findings will contribute to Antarctic science as well as the broader study of riparian zones and hydrologic margins worldwide. Graduate students and undergraduate students will be involved with fieldwork and research projects. Information will be disseminated through a project web site, and outreach activities will include science education in local elementary, middle and high schools near the three universities involved.", "east": 163.33, "geometry": "POINT(162.465 -77.575)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -77.4, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gooseff, Michael N.; Barrett, John; Takacs-Vesbach, Cristina", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website; USAP-DC", "science_programs": null, "south": -77.75, "title": "Collaborative Research: Hydrologic Controls over Biogeochemistry and Microbial Community Structure and Function across Terrestrial/Aquatic Interfaces in a Polar Desert", "uid": "p0000340", "west": 161.6}, {"awards": "0127022 Jeffrey, Wade", "bounds_geometry": "POLYGON((-177.639 -43.5676,-143.1091 -43.5676,-108.5792 -43.5676,-74.0493 -43.5676,-39.5194 -43.5676,-4.9895 -43.5676,29.5404 -43.5676,64.0703 -43.5676,98.6002 -43.5676,133.1301 -43.5676,167.66 -43.5676,167.66 -46.99877,167.66 -50.42994,167.66 -53.86111,167.66 -57.29228,167.66 -60.72345,167.66 -64.15462,167.66 -67.58579,167.66 -71.01696,167.66 -74.44813,167.66 -77.8793,133.1301 -77.8793,98.6002 -77.8793,64.0703 -77.8793,29.5404 -77.8793,-4.9895 -77.8793,-39.5194 -77.8793,-74.0493 -77.8793,-108.5792 -77.8793,-143.1091 -77.8793,-177.639 -77.8793,-177.639 -74.44813,-177.639 -71.01696,-177.639 -67.58579,-177.639 -64.15462,-177.639 -60.72345,-177.639 -57.29228,-177.639 -53.86111,-177.639 -50.42994,-177.639 -46.99877,-177.639 -43.5676))", "dataset_titles": "Expedition Data; Ross Sea microbial biomass and production", "datasets": [{"dataset_uid": "600029", "doi": "10.15784/600029", "keywords": "Biota; Chemistry:fluid; Chemistry:Fluid; CTD Data; Microbiology; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "Jeffrey, Wade H.", "repository": "USAP-DC", "science_program": null, "title": "Ross Sea microbial biomass and production", "url": "https://www.usap-dc.org/view/dataset/600029"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "001690", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0304B"}], "date_created": "Thu, 12 Jun 2008 00:00:00 GMT", "description": "Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea.", "east": 167.66, "geometry": "POINT(-4.9895 -60.72345)", "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 PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; 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 MSBS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUORESCENCE MICROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e GO-FLO BOTTLES", "is_usap_dc": true, "keywords": "R/V NBP; B-15J", "locations": "B-15J", "north": -43.5676, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jeffrey, Wade H.; Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -77.8793, "title": "Collaborative Proposal: Interactive Effects of UV Radiation and Vertical Mixing on Phytoplankton and Bacterial Productivity of Ross See Phaeocystis Blooms", "uid": "p0000578", "west": -177.639}, {"awards": "9526556 Sowers, Todd", "bounds_geometry": "POINT(-148.3023 -81.403)", "dataset_titles": "Carbon-13 Isotopic Composition of Atmospheric Methane in Firn Air, South Pole and Siple Dome, Antarctica", "datasets": [{"dataset_uid": "609310", "doi": "10.7265/N5ST7MR2", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Siple Dome; Snow/ice; Snow/Ice; South Pole", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Carbon-13 Isotopic Composition of Atmospheric Methane in Firn Air, South Pole and Siple Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609310"}], "date_created": "Mon, 09 Jul 2007 00:00:00 GMT", "description": "This award is for support for a program to reconstruct records of the isotopic composition of paleoatmospheric methane and nitrous oxide covering the last 200,000 years. High resolution measurements of the carbon-13 isotopic composition of methane from shallow ice cores will help to determine the relative contributions of biogenic (wetlands, rice fields and ruminants) and abiogenic (biomass burning and natural gas) methane emissions which have caused the concentrations of this gas to increase at an exponential rate during the anthropogenic period. Isotopic data on methane and nitrous oxide over glacial/interglacial timescales will help determine the underlying cause of the large concentration variations that are known to occur. This project will make use of a new generation mass spectrometer which is capable of generating precise isotopic information on nanomolar quantities of methane and nitrous oxide, which means that samples can be 1000 times smaller than those needed for a standard isotope ratio instrument. The primary objective of the work is to further our understanding of the biogeochemical cycles of these two greenhouse gases throughout the anthropogenic period as well as over glacial interglacial timescales.", "east": -148.3023, "geometry": "POINT(-148.3023 -81.403)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core; Firn Air Isotope Measurements; Ice Core Chemistry; Firn Isotopes; Stable Isotopes; Methane; Carbon; Paleoclimate; LABORATORY; Siple Dome; Antarctica; Ice Core Data; Firn Air Isotopes; Antarctic Ice Sheet", "locations": "Antarctica; Antarctic Ice Sheet; Siple Dome", "north": -81.403, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Sowers, Todd A.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.403, "title": "Constructing Paleoatmospheric Records of the Isotopic Composition of Methane and Nitrous Oxide", "uid": "p0000611", "west": -148.3023}, {"awards": "0230149 McGwire, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 04 Jun 2007 00:00:00 GMT", "description": "This award supports the development of novel methods for digital image analysis of glacial ice cores that are stored at the National Ice Core Laboratory (NICL) in Denver, Colorado. Ice cores are a critical source of information on how Earth has changed over time, since indicators of local climate (snow accumulation, temperature), regional characteristics (wind-blown materials such as sea salt, dust and pollen), global processes (e.g., CO2, methane), and even extraterrestrial influences (cosmogenic isotopes) are stored in the ice on a common time scale. This project will develop a high-resolution optical scanning system for laboratory curation of ice core images, internet-based search and retrieval capabilities, a digital image analysis system specifically for ice core studies, and methods to integrate ice core image analysis with other dating methods. These tools will be developed and tested in conjunction with scientific investigations of NICL holdings. Optical scanning and analysis tools will improve understanding of the historical development of the ice collected from a particular location and will help to resolve challenges such as ice that has lost stratigraphic order through flow processes. \u003cbr/\u003eBy providing permanent online digital archives of ice core images, this project will greatly improve the documentation and availability of ice core data while reducing time and costs for subsequent scientific investigations. Using the internet, ice core scientists will be able to determine the appropriateness of specific NICL holdings for various scientific studies. By optically scanning ice cores as they are processed at NICL, any researcher will be able to examine an ice core in similar detail to the few investigators who were fortunate enough to observe it before modifications from sampling and storage. Re-examination of cores could be done decades later by anyone at any location, which is not possible now because only the interpretation of the original observer is recorded. Integration of digital image data into ice core analysis will speed discovery, allow collaborative interpretation, and enhance consistency of analysis to improve ice core dating, identification of melt layers, location of flow disturbances, and more. The equipment will be housed at NICL and will be available to the broad community, improving scientific infrastructure.\u003cbr/\u003eThis work will also have numerous broader impacts. Ice core science addresses fundamental questions of human interest related to global warming, abrupt climate change, biogeochemical cycling, and more. The principal investigators broadly disseminate their scientific findings through numerous outlets, ranging from meeting with government officials, chairing and serving on NRC panels, writing popular books and articles, publishing in scientific literature, teaching classes, talking to civic groups, and appearing on radio and television. The results from ice core analyses have directly informed policymakers and will continue to do so. Thus, by improving ice core science, this projectl will benefit society.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e VISUAL OBSERVATIONS", "is_usap_dc": false, "keywords": "Image; Ice Core; Not provided; Scanner; Stratigraphy", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "McGwire, Kenneth C.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Digital Optical Imaging of Ice Cores for Curation and Scientific Applications", "uid": "p0000735", "west": null}, {"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": "Tatum, Cheryl; Saltzman, Eric; Aydin, Murat; Williams, Margaret", "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": "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"}, {"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"}], "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": "0125900 Sowers, Todd", "bounds_geometry": "POINT(-148.8 -81.7)", "dataset_titles": null, "datasets": null, "date_created": "Thu, 26 May 2005 00:00:00 GMT", "description": "0125900\u003cbr/\u003eSowers\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to improve the understanding of the biogeochemical processes that control CH4 emissions. Records of the concentration of methane in trapped gases in ice tell us about changes in atmospheric loading through time. Such records do not, however, provide information on the individual sources or sinks. One way to refine our understanding of the cycling of bioactive trace gases like methane is to use stable isotope records of trapped gases in ice cores. This project will measure the Deuterium/Hydrogen (D/H) ratio of methane trapped in shallow/recent ice (covering the last ~ 200 years) at Siple Dome, Antarctica. The proposed work will complement current efforts to measure the carbon-13 isotope ratio of methane in ice cores and will provide fundamental information on the various sources and sinks of atmospheric methane over the last 200 years.", "east": -148.8, "geometry": "POINT(-148.8 -81.7)", "instruments": null, "is_usap_dc": false, "keywords": "Siple Dome; Not provided; Ch4; Methane; Antarctica; Ice Core", "locations": "Siple Dome; Antarctica", "north": -81.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -81.7, "title": "Constructing the first D/H record of atmospheric methane covering the last two centuries.", "uid": "p0000754", "west": -148.8}, {"awards": "0125981 Sowers, Todd", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 05 May 2005 00:00:00 GMT", "description": "0125981\u003cbr/\u003eSowers\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to construct an isotopic record of atmospheric methane and nitrous oxide over the last century from South Pole firn air. Over the last 150 years, atmospheric methane and nitrous oxide concentrations have risen in response to increased emissions from various anthropogenic activities. As this trend is liable to continue in the foreseeable future, it is important to understand the biogeochemical processes that contribute to the emissions of these two greenhouse gases. In this context, records of the variations in the atmospheric loading of trace gases found in ice cores and interstitial spaces in the snow near the surface of the ice sheet (firn air) provide fundamental boundary conditions for reconstructing historical emission records. One way to improve our understanding of the cycling of bioactive trace gases and their emission records is to use stable isotope tracers, which have been recorded in the ice cores and firn air. This project will develop records of carbon-13 and deuterium isotope ratios of methane, as well as the nitrogen-15, oxygen-18 and the isotopomer composition of nitrous oxide trapped in firn air samples collected in January 2001 at the South Pole. These measurements will allow isotopic records of these atmospheric gases to be reconstructed throughout the 20th century. Such records will help to establish the relative contribution of individual sources with a higher degree of confidence than is currently available.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -62.83, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Sowers, Todd A.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Generating an Isotopic Record of Atmospheric Methane and Nitrous Oxide Over the Last Century from South Pole Firn Air", "uid": "p0000086", "west": -180.0}, {"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": "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"}, {"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": "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/"}], "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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Project Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Dataset Links and Repositories | Abstract | Bounds Geometry | Geometry | Selected | Visible | |||||||||||||
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Projecting the Biological Carbon Pump and Climate Feedback in the Rapidly Changing West Antarctic Peninsula: A Hybrid Modeling Study
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2332062 |
2024-08-05 | Kim, Heather | No dataset link provided | 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.<br/><br/>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. | 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)) | POINT(-64 -67) | false | false | |||||||||||||
None
|
None | 2024-07-23 | Riddell-Young, Benjamin; Brook, Edward J.; Iseli, Rene; Lee, James; Schmitt, Jochen; Fischer, Hubertus; Bauska, Thomas; Menking, James; Clark, Reid |
|
None | None | None | false | false | |||||||||||||
Siderophore utilization by dinoflagellates as a strategy for iron acquisition
|
2207011 |
2024-03-04 | Granger, Julie; Lin, Senjie | No dataset link provided | Iron is a limiting nutrient for primary production in 30% of the global ocean, including the Southern Ocean. Dinoflagellates thrive in a wide variety of coastal and oceanic environments, including iron-limited regions. As iron is a biologically essential element for the growth and proliferation of marine algae, dinoflagellates may have evolved strategic mechanisms to combat iron limitation. Presently, these mechanisms have been scantly investigated in dinoflagellates. Here, we compare the growth response of the well-studied diatom Thalasiossira weissflogii to that of dinoflagellates Amphidinium carterae, Heterocapsa triquetra, and Symbiodinium tridacnidorum to different iron conditions: (a) iron-replete medium, (b) iron-limited medium, and (c) iron-limited medium supplemented with the siderophore Deferoxamine B (DFB). Preliminary observations suggest that A. carterae is able to assimilate iron bound to DFB, in contrast to T. weissflogii and Heterocapsa triquetra. A survey of the transcriptome of A. carterae suggests that it possess genes analogous to the TonB-dependent receptors (TBDRs) associated with iron-siderophore transport in prokaryotes. Additional species of dinoflagellates will be observed to investigate the ubiquity of this strategy in dinoflagellates. A more comprehensive understanding of dinoflagellate acclimation to low iron conditions is key to understanding their ecophysiology and the biogeochemical dynamics of iron-limited regions. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
LTER: MCM6 - The Roles of Legacy and Ecological Connectivity in a Polar Desert Ecosystem
|
2224760 |
2023-11-14 | 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. |
|
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. | POINT(162.87 -77) | POINT(162.87 -77) | false | false | |||||||||||||
Southern Ocean Biogeochemistry Control on Short-Lived Ozone-Depleting Substances and Impacts on the Climate System
|
2032328 |
2023-07-27 | Apel, Eric | No dataset link provided | A class of small molecules, very short-lived substances (VSLS; e.g. CHBr3,CH2Br2, and CH3I) are important components in the climate system where they act as tropospheric ozone destroyers as described in the multilateral environmental Montreal Protocol on Substances that Deplete the Ozone Layer. The Southern Ocean represents a key component in the climate system and has a critical role in other global biogeochemical cycles. This project will use the NSF/NCAR Community Earth System Model (CESM) with a newly developed online air-sea exchange framework, to evaluate biogeochemical controls on the marine sources of VSLS in the Southern Ocean as well as the Southern Hemisphere. A machine-learning approach will be used to couple ocean biogeochemistry with air-sea exchange for these compounds. A variety of oceanic and atmospheric observations of VSLS will be used to evaluate a unique oceanic VSLS inventory. In particular, the recent ORCAS field campaign provides a unique opportunity to examine Southern Ocean VSLS emissions, and their impacts from ocean biogeochemistry, meteorology and sea ice cycles. The project will also support a postdoctoral early-career researcher, and a specific effort of this project is STEM education and public outreach activities. The research team will extend opportunities to high school and undergraduate students so they may gain experience in the coupled ocean and atmospheric sciences, including exposure to and experience in programming and modeling. 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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
CAREER: Experimentally Testing the Role of Sympagic Algae in Sea-ice Environments using a Laboratory Scale Ice-tank.
|
2142491 |
2023-07-26 | Young, Jodi | No dataset link provided | The aims of this CAREER proposal are to gain a greater understanding of the role of sympagic algae in Antarctic marine ecosystems with the goal to better parameterize their role in biogeochemical and ecosystem processes across dynamic environments. Specifically, this proposal will apply a laboratory-scale, ice-tank system that recreates the seasonal cycle of sea ice in the laboratory for the purpose of studying sympagic microbes to study the following questions: 1.1 Starting with a late autumn, mixed phytoplankton community, how do different algal species specialize to sea ice, seawater and flooded snow/ice habitats over winter? 1.2 What are the relationships between different methods of measuring primary production (fluorescence, O2 production, CO2 drawdown) in sea ice? Does this differ from seawater? 1.3 Does the presence of sea-ice algae influence the physical structure of sea ice? 1.4 How does the release of compatible solutes from algae during ice melt influence the dissolved organic pool? In addition, I propose to integrate educational activities with my research goals. This includes development of an educational program at the university and K-12 level on Antarctic Sciences that develops critical thinking and quantitative skills, encourages STEM participation from underrepresented groups and establishes an interactive network of Antarctic researchers to broaden research opportunities. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
LTER: Ecological Response and Resilience to “Press-Pulse” Disturbances and a Recent Decadal Reversal in Sea Ice Trends Along the West Antarctic Peninsula
|
2026045 2224611 |
2023-07-26 | Schofield, Oscar; Steinberg, Deborah |
|
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. 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 Nio Southern Oscillation and Southern Annular Mode) are being studied at multiple time scales from diel, seasonal, interannual, to decadal intervals, and space scalesfrom 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. | 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)) | POINT(-71.26400000000001 -66.8895) | false | false | |||||||||||||
Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores
|
1745078 |
2023-05-01 | Brook, Edward | This project will develop methods to measure the ratios of carbon-13 to carbon-12, and heavy to light hydrogen in methane in air trapped in ice cores. The ratios of the different forms of carbon and hydrogen are "fingerprints" of different sources of this gas in the past--for example wetlands in the tropics versus methane frozen in the sea floor. Once the analysis method is developed, the measurements will be used to examine why methane changed abruptly in the past, both during the last ice age, and during previous warm periods. The data will be used to understand how methane sources like wildfires, methane hydrates, and wetlands respond to climate change. This information is needed to understand future risks of large changes in methane in the atmosphere as Earth warms. <br/><br/>The project involves two tasks. First, the investigators will build and test a gas extraction system for methane isotopic measurements using continuous flow methods, with the goal of equaling or bettering the precision attained by the few other laboratories that make these measurements. The system will be interfaced with existing mass spectrometers at Oregon State University. The system consists of a vacuum chamber and sequence of traps, purification columns, and furnaces that separate methane from other gases and convert it to carbon dioxide or hydrogen for mass spectrometry. Second, the team will measure the isotopic composition of methane across large changes in concentration associated with two past interglacial periods and during abrupt methane changes of the last ice age. These measurements will be used to understand if the main reason for these concentration changes is climate-driven changes in emissions from wetlands, or whether other sources are involved, for example methane hydrates or wildfires.<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. | 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)) | POINT(0 -89.999) | false | false | ||||||||||||||
ANT LIA: Collaborative Research: Mixotrophic Grazing as a Strategy to meet Nutritional Requirements in the Iron and Manganese Deficient Southern Ocean
|
2240780 |
2023-03-13 | Cohen, Natalie; Millette, Nicole | No dataset link provided | Mixotrophic microorganisms that are capable of both photosynthetic and heterotrophic forms of metabolism are key contributors to primary productivity and organic carbon remineralization in the Southern Ocean. However, uncertainties in their grazing behavior and physiology prevent an accurate understanding of microbial food web dynamics and biogeochemical cycling in the Antarctic ecosystem. Polar mixotrophs have evolved to withstand extreme seasonality, including variable light, sea ice, temperature, and micronutrient concentrations. In particular, the Southern Ocean appears to be the only region of the world’s ocean where the bioessential trace metals iron (Fe) and manganese (Mn) are low enough to inhibit photosynthetic growth. The molecular physiology of mixotrophs experiencing Fe and Mn growth limitation has not yet been examined, and we lack an understanding of how seasonal changes in the availability of these micronutrients influence mixotrophic growth dynamics. We aim to examine whether grazing affords mixotrophs an ecological advantage in the Fe and Mn-deficient Southern Ocean, and to characterize the shifts in metabolic processes that occur during transitions in micronutrient conditions. Culture studies will directly measure growth responses, grazing behavior, and changes in elemental stoichiometry in response to Fe and Mn limitation. Transcriptomic analyses will reveal the metabolic underpinnings of trophic behavior and micronutrient stress responses, with implications for key biogeochemical processes such as carbon fixation, remineralization, and nutrient cycling. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
ANT LIA: Collaborative Research: Adaptations of Southern Ocean Diatoms to Manganese Scarcity: Can Physiological Ingenuity Overcome Unfavorable Chemistry?
|
2149070 |
2023-03-13 | Hawco, Nicholas; Cohen, Natalie | No dataset link provided | This proposal represents collaborative research to explore manganese (Mn) limitation in Antarctic diatoms by two early career investigators. Diatoms are central players in the Southern Ocean carbon cycle, where the micronutrient chemistry is fundamentally different from other oceans. The Southern Ocean is characterized by widespread low Mn, coupled with high zinc (Zn). High Zn levels are potentially toxic to diatoms as Zn can competitively inhibit Mn uptake and metabolism, compromising the ability of building critical cellular components, thus impacting the biological pump. Using culture experiments with a matrix of micronutrient treatments (Mn, Zn, Fe) and irradiances, and using physiological and transcriptomic approaches, along with biochemical principles, the Principal Investigators will address the central hypothesis (that diatoms from the Southern Ocean possess unique physiological mechanisms to adapt to low Mn/high Zn) by quantifying rates of uptake and transporter binding constants. The transcriptomics approach will help to identify candidate genes that may provide Antarctic diatoms physiological mechanisms in low Mn/high Zn environment. The project does not require fieldwork but instead would make use of culture experiments with 4 diatom species (3 Antarctic, and 1 temperate). The proposed approach will also enable the goal of developing biomarker(s) for assessing Mn stress or Zn toxicity and results from the physiological experiments will help parameterize models of micronutrient limitation 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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
High Resolution Underway Air-Sea Observations in Drake Passage for Climate Science
|
2001646 1542902 |
2023-03-03 | Chereskin, Teresa; Sprintall, Janet |
|
The Antarctic Circumpolar Current (ACC) is the largest current on the planet, flowing west to east around Antarctica, forming a barrier that separates warmer waters to the north from colder waters to the south. Ocean eddies (like atmospheric storms) break through the ACC barrier, transferring heat across the ACC towards Antarctica. When warmer ocean waters intrude onto the Antarctic continental shelves, they contribute to glacial melt and ice shelf retreat. Over the past several decades, the Southern Ocean has warmed and winds have increased due to climate change. Somewhat surprisingly the ACC, though pushed by faster winds, has not accelerated; a faster current would present a stronger barrier to heat transfer. Instead, ocean eddies have increased. These eddies are concentrated at 6-7 "hot spots". Drake Passage is one of these hot spots. As the narrowest land gap on the entire circumpolar path of the ACC, Drake Passsage is an ideal monitoring spot. However, it is also one of the windiest and roughest stretches of water on the globe. The only ship that crosses Drake Passage year-round is the USAP supply vessel for Palmer Station, making it a unique platform to monitor the currents and temperature with a minimum of personnel and resources. The Drake Passage time series of upper ocean currents and temperature is now in its 24th year. The upper ocean temperature measurements have found significant warming in Drake Passage. The upper ocean current measurements have confirmed that the ACC has remained steady on average but have also revealed a complicated filamented current structure. Combining temperature and current measurements has provided a better understanding of heat transfer across the ACC by eddies. The time series has also provided valuable ground-truth for satellite measurements and for numerical model predictions looking at the entire ACC. Our studies are focused on examining low-frequency variability - seasonal, interannual, and decadal - in order to provide baselines from which to evaluate and interpret physical and biogeochemical changes occurring in the Southern Ocean. | 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)) | POINT(-61.5 -59) | false | false | |||||||||||||
Collaborative Research: Investigating Biogeochemical Fluxes and Linkages To Climate Change With Multi-Scale Observations In The Drake Passage
|
1543457 1543511 |
2023-02-22 | Munro, David; Sweeney, Colm; Lovenduski, Nicole S; Stephens, Britton | The Southern Ocean plays a key role in modulating the global carbon cycle, but the size and even the sign of the flux of carbon dioxide between the ocean and atmosphere in this region is 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. More specifically, this project is a continuation of the collection of underway upper ocean measurements of the surface partial pressure of carbon dioxide during crossings of the Drake Passage by the Antarctic Research and Supply Vessel Laurence M. Gould. This project also includes collection and analysis of discrete samples relevant to ocean carbon cycle studies including macronutrient concentrations, total carbon dioxide concentrations, and the carbon isotopic composition of total carbon dioxide. 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. | 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)) | POINT(-64 -60) | false | false | ||||||||||||||
None
|
None | 2023-01-30 | Liu, Xiaodong |
|
None | None | None | false | false | |||||||||||||
Collaborative Research: Understanding the Massive Phytoplankton Blooms over the Australian-Antarctic Ridge
|
2135186 2135185 2135184 |
2022-09-30 | Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph | No dataset link provided | Part 1. Phytoplankton blooms throughout the world support critical marine ecosystems and help remove harmful CO2 from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either the continental margin or sea-ice. However, recent work demonstrates that hydrothermal vents may be an additional iron source for phytoplankton blooms. This enhancement of phytoplankton productivity by different iron sources supports rich marine ecosystems and leads to the sequestration of C in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton blooms along the southern boundary of the Antarctic Circumpolar Current just north of the Ross Sea. It will also lead towards a better understanding of the overall impact of hydrothermal activity on the C cycle in the Southern Ocean, which appears to trigger local hotspots of enhanced biological activity which are a potential as a sink for atmospheric CO2. This project will encourage the participation of underrepresented groups in ocean sciences, as well as providing educational opportunities for high school and undergraduate students, through three different programs. Stanford University’s Summer Undergraduate Research in Geoscience and Engineering (SURGE) program provides undergraduates from different US universities and diverse cultural backgrounds the opportunity to spend a summer doing a research project at Stanford. The Stanford Earth Summer Undergraduate Research Program (SESUR) is for Stanford undergraduates who want to learn more about environmental science by performing original research. Finally, Stanford’s School of Earth, Energy, and Environmental Sciences High School Internship Program enables young scientists to serve as mentors, prepares high school students for college, and serves to strengthen the partnership between Stanford and local schools. Students present their results at the Fall AGU meeting as part of the AGU Bright STaRS program. This project will form the basis of at least two Ph.D. dissertations. The Stanford student will participate in Stanford’s Woods Institute Rising Environmental Leaders Program (RELP), a year-round program that helps graduate students hone their leadership and communication skills to maximize the impact of their research. The graduate student will also participate in Stanford’s Grant Writing Academy where they will receive training in developing and articulating research strategies to tackle important scientific questions. Part 2. This interdisciplinary program combines satellite and ship-based measurements of a large poorly understood phytoplankton bloom (the AAR bloom) in the northwestern Ross Sea sector of the Southern Ocean with a detailed modeling study of the physical processes linking deep dissolved iron (DFe) reservoirs to the surface phytoplankton bloom. Prior to the cruise, we will implement a numerical model (CROCO) for our study region so that we can better understand the circulation, plumes, turbulence, fronts, and eddy field around the AAR bloom and how they transport and mix hydrothermally produced DFe vertically. Post cruise, observations of the vertical distribution of 3He (combined with DMn and DFe), will be used as initial conditions for a passive tracer in the model, and tracer dispersal will be assessed to better quantify the role of the various turbulent processes in upwelling DFe-rich waters to the upper ocean. The satellite-based component of the program will characterize the broader sampling region before, during, and after our cruise. During the cruise, our automated software system at Stanford University will download and process images of sea ice concentration, Chl a concentration, sea surface temperature (SST), and SSH and send them electronically to the ship. Operationally, our goal is to use all available satellite data and preliminary model results to target shipboard sampling both geographically and temporally to optimize sampling of the AAR bloom. We will use available BGC-Argo float data to help characterize the AAR bloom. In collaboration with SOCCOM, we will deploy additional BGC-Argo floats (if available) during our transit through the study area to allow us to better characterize the bloom. The centerpiece of our program will be a 40-day process study cruise in austral summer. The cruise will consist of an initial “radiator” pattern of hydrographic surveys/sections along the AAR followed by CTDs to selected submarine volcanoes. When/if eddies are identified, they will be sampled either during or after the initial surveys. The radiator pattern, or parts thereof, will be repeated 2-3 times. Hydrographic survey stations will include vertical profiles of temperature, salinity, oxygen, oxidation-reduction potential, light scatter, and PAR (400-700 nm). Samples will be collected for trace metals, ligands, 3He, and total suspended matter. Where intense hydrothermal activity is identified, samples for pH and total CO2 will also be collected to characterize the hydrothermal system. Water samples will be collected for characterization of macronutrients, and phytoplankton physiology, abundance, species composition, and size. During transits, we will continuously measure atmospheric conditions, current speed and direction, and surface SST, salinity, pCO2, and fluorescence from the ship’s systems to provide detailed maps of these parameters. The ship will be used as a platform for conducting phytoplankton DFe bioassay experiments at key stations throughout the study region both inside and outside the bloom. We will also perform detailed comparisons of algal taxonomic composition, physiology, and size structure inside and outside the bloom to determine the potential importance of each community on local biogeochemistry. | POLYGON((155 -61,156.5 -61,158 -61,159.5 -61,161 -61,162.5 -61,164 -61,165.5 -61,167 -61,168.5 -61,170 -61,170 -61.2,170 -61.4,170 -61.6,170 -61.8,170 -62,170 -62.2,170 -62.4,170 -62.6,170 -62.8,170 -63,168.5 -63,167 -63,165.5 -63,164 -63,162.5 -63,161 -63,159.5 -63,158 -63,156.5 -63,155 -63,155 -62.8,155 -62.6,155 -62.4,155 -62.2,155 -62,155 -61.8,155 -61.6,155 -61.4,155 -61.2,155 -61)) | POINT(162.5 -62) | false | false | |||||||||||||
Collaborative Research: US GEOTRACES GP17-ANT: Dissolved concentrations, isotopes, and colloids of the bioactive trace metals
|
2123491 2123354 2123333 |
2022-09-08 | Conway, Timothy; Fitzsimmons, Jessica; John, Seth | No dataset link provided | The goal of the international GEOTRACES program is to understand the distributions of trace chemical elements and their isotopes (TEIs) in the oceans. Many trace metals such as iron are essential for life and thus considered nutrients for phytoplankton growth, with trace metal cycling being especially important for influencing carbon cycling in the iron-limited Southern Ocean, where episodic supply of iron from a range of different external sources is important. The primary goal of this project is to measure the dissolved concentrations, size partitioning, and dissolved isotope signature of Fe on a transect of water-column stations throughout the Amundsen Sea and surrounding region of the Antarctic Margin, as part of the GP17-ANT Expedition. The secondary goal of this project is to analyze the concentrations and size partitioning of the trace metals manganese, zinc, copper, cadmium, nickel, and lead in all water-column samples, measure the isotope ratios of zinc, cadmium, nickel, and copper in a subset of water column samples, and measure the Fe isotopic signature of aerosols, porewaters, and particles. Observations from this project will be incorporated into regional and global biogeochemistry models to assess TEI cycling within the Amundsen Sea and implications for the wider Southern Ocean. This project spans three institutions, four graduate students, undergraduate students, and will provide ultrafiltered samples and data to other PIs as service. The US GEOTRACES GP17 ANT expedition, planned for austral summer 2023/2024 aims to determine the distribution and cycling of trace elements and their isotopes in the Amundsen Sea Sector (100-135°W) of the Antarctic Margin. The cruise will follow the Amundsen Sea ‘conveyor belt’ by sampling waters coming from the Antarctic Circumpolar Current onto the continental shelf, including near the Dotson and Pine Island ice shelves, the productive Amundsen Sea Polynya (ASP), and outflowing waters. Episodic addition of dissolved Fe and other TEIs from dust, ice-shelves, melting ice, and sediments drive seasonal primary productivity and carbon export over the Antarctic shelf and offshore into Southern Ocean. Seasonal coastal polynyas such as the highly productive ASP thus act as key levers on global carbon cycling. However, field observations of TEIs in such regions remain scarce, and biogeochemical cycling processes are poorly captured in models of ocean biogeochemistry. The investigators will use their combined analytical toolbox, in collaboration with the diagnostic chemical tracers and regional models of other funded groups to address four main objectives: 1) What is the relative importance of different sources in supplying Fe and other TEIs to the ASP? 2) What is the physiochemical speciation of this Fe, and its potential for transport? 3) How do biological uptake, scavenging and regeneration in the ASP influence TEI distributions, stoichiometry, and nutrient limitation? 4) What is the flux and signature of TEIs transported offshore to the ACC and Southern Ocean? | POLYGON((-135 -66,-131.5 -66,-128 -66,-124.5 -66,-121 -66,-117.5 -66,-114 -66,-110.5 -66,-107 -66,-103.5 -66,-100 -66,-100 -67,-100 -68,-100 -69,-100 -70,-100 -71,-100 -72,-100 -73,-100 -74,-100 -75,-100 -76,-103.5 -76,-107 -76,-110.5 -76,-114 -76,-117.5 -76,-121 -76,-124.5 -76,-128 -76,-131.5 -76,-135 -76,-135 -75,-135 -74,-135 -73,-135 -72,-135 -71,-135 -70,-135 -69,-135 -68,-135 -67,-135 -66)) | POINT(-117.5 -71) | false | false | |||||||||||||
ANT LIA: Collaborative Research: Genetic Underpinnings of Microbial Interactions in Chemically Stratified Antarctic Lakes
|
1937595 1937546 |
2022-07-27 | Morgan-Kiss, Rachael; Briggs, Brandon | No dataset link provided | Microbial communities are of more than just a scientific curiosity. Microbes represent the single largest source of evolutionary and biochemical diversity on the planet. They are the major agents for cycling carbon, nitrogen, phosphorus, and other elements through the ecosystem. Despite their importance in ecosystem function, microbes are still generally overlooked in food web models and nutrient cycles. Moreover, microbes do not live in isolation: their growth and metabolism are influenced by complex interactions with other microorganisms. This project will focus on the ecology, activity and roles of microbial communities in Antarctic Lake ecosystems. The team will characterize the genetic underpinnings of microbial interactions and the influence of environmental gradients (e.g. light, nutrients, oxygen, sulfur) and seasons (e.g. summer vs. winter) on microbial networks in Lake Fryxell and Lake Bonney in the Taylor Valley within the McMurdo Dry Valley region. Finally, the project furthers the NSF goals of training new generations of scientists by including undergraduate and graduate students, a postdoctoral researcher and a middle school teacher in both lab and field research activities. This partnership will involve a number of other outreach training activities, including visits to classrooms and community events, participation in social media platforms, and webinars. <br/><br/>Part II: Technical description: Ecosystem function in the extreme Antarctic Dry Valleys ecosystem is dependent on complex biogeochemical interactions between physiochemical environmental factors (e.g. light, nutrients, oxygen, sulfur), time of year (e.g. summer vs. winter) and microbes. Microbial network complexity can vary in relation to specific abiotic factors, which has important implications on the fragility and resilience of ecosystems under threat of environmental change. This project will evaluate the influence of biogeochemical factors on microbial interactions and network complexity in two Antarctic ice-covered lakes. The study will be structured by three main objectives: 1) infer positive and negative interactions from rich spatial and temporal datasets and investigate the influence of biogeochemical gradients on microbial network complexity using a variety of molecular approaches; 2) directly observe interactions among microbial eukaryotes and their partners using flow cytometry, single-cell sorting and microscopy; and 3) develop metabolic models of specific interactions using metagenomics. Outcomes from amplicon sequencing, meta-omics, and single-cell genomic approaches will be integrated to map specific microbial network complexity and define the role of interactions and metabolic activity onto trends in limnological biogeochemistry in different seasons. These studies will be essential to determine the relationship between network complexity and future climate conditions. Undergraduate researchers will be recruited from both an REU program with a track record of attracting underrepresented minorities and two minority-serving institutions. To further increase polar literacy training and educational impacts, the field team will include a teacher as part of a collaboration with the successful NSF-funded PolarTREC program and participation in activities designed for public outreach.<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. | POLYGON((162 -77.616667,162.1 -77.616667,162.2 -77.616667,162.3 -77.616667,162.4 -77.616667,162.5 -77.616667,162.6 -77.616667,162.7 -77.616667,162.8 -77.616667,162.9 -77.616667,163 -77.616667,163 -77.6283336,163 -77.6400002,163 -77.6516668,163 -77.6633334,163 -77.67500000000001,163 -77.68666660000001,163 -77.69833320000001,163 -77.7099998,163 -77.7216664,163 -77.733333,162.9 -77.733333,162.8 -77.733333,162.7 -77.733333,162.6 -77.733333,162.5 -77.733333,162.4 -77.733333,162.3 -77.733333,162.2 -77.733333,162.1 -77.733333,162 -77.733333,162 -77.7216664,162 -77.7099998,162 -77.69833320000001,162 -77.68666660000001,162 -77.67500000000001,162 -77.6633334,162 -77.6516668,162 -77.6400002,162 -77.6283336,162 -77.616667)) | POINT(162.5 -77.67500000000001) | false | false | |||||||||||||
Quantifying Processes Driving Interannual Variability in the Biological Carbon Pump in the Western Antarctic Peninsula
|
1951090 |
2022-06-03 | Stukel, Michael |
|
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.<br/><br/> 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.<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. | 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)) | POINT(-71 -66.5) | false | false | |||||||||||||
ANT LIA - Viral Ecogenomics of the Southern Ocean: Unifying Omics and Ecological Networks to Advance our Understanding of Antarctic Microbial Ecosystem Function
|
2055455 |
2022-06-03 | Duhaime, Melissa; Zaman, Luis | No dataset link provided | Part 1: Non-technical description: It is well known that the Southern Ocean plays an important role in global carbon cycling and also receives a disproportionately large influence of climate change. The role of marine viruses on ocean productivity is largely understudied, especially in this global region. This team proposes to use combination of genomics, flow cytometry, and network modeling to test the hypothesis that viral biogeography, infection networks, and viral impacts on microbial metabolism can explain variations in net community production (NCP) and carbon cycling in the Southern Ocean. The project includes the training of a postdoctoral scholar, graduate students and undergraduate students. It also includes the development of a new Polar Sci ReachOut program in partnership with the University of Michigan Museum of Natural History especially targeted to middle-school students and teachers and the general public. The team will also produce a Science for Tomorrow (SFT) program for use in middle schools in metro-Detroit communities and lead a summer Research Experience for Teachers (RET) fellows. Part 2: Technical description: The study will leverage hundreds of existing samples collected for microbes and viruses from the Antarctic Circumpolar Expedition (ACE). These samples provide the first contiguous survey of viral diversity and microbial communities around Antarctica. Viral networks are being studied in the context of biogeochemical data to model community networks and predict net community production (NCP), which will provide a way to evaluate the role of viruses in Southern Ocean carbon cycling. Using cutting edge molecular and flow cytometry approaches, this project addresses the following questions: 1) How/why are Southern Ocean viral populations distributed across environmental gradients? 2a) Do viruses interfere with "keystone" metabolic pathways and biogeochemical processes of microbial communities in the Southern Ocean? 2b) Does nutrient availability or other environmental variables drive changes in virus-microbe infection networks in the Southern Ocean? Results will be used to develop and evaluate generative models of NCP predictions that incorporate the importance of viral traits and virus-host interactions. 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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Exploring the Functional Role of Antarctic Plants during Terrestrial Succession
|
1932876 |
2022-04-14 | Ball, Becky | No dataset link provided | Part I: Non-technical summary<br/>The Antarctic Peninsula warmed very rapidly in the late part of the 20th century, much faster than the global average, and this warming is predicted to resume and continue over the rest of the 21st century. One consequence of this rapid warming is the melting and subsequent retreat of glaciers, leading to an increase in newly-exposed land on the Peninsula that was previously covered with ice. Once new terrain is exposed, the process of ecological succession begins, with the arrival of early-colonizing plants, such as moss and lichens, and soil organisms - a process commonly referred to as the “greening” of Antarctica. Early stages of succession will be an increasingly common feature on the Antarctic Peninsula, but the mechanisms by which they occur on the Antarctic continent is not well understood. Once the plants have established on the newly-exposed soil, they can change many important properties, such as water dynamics, nutrient recycling, soil development, and habitat for microscopic organisms, which will ultimately determine the structure and functioning of the future ecosystem as it develops. These relationships between vegetation, soil, and the associated microorganisms, referred to as “plant-soil” interactions, are something we know virtually nothing about. This project will be the first to make a comprehensive study of how the type of colonizing plant, and the expansion of those plants from climate change, will influence terrestrial ecosystems in Antarctica. Understanding these processes is critical to understanding how the greening Antarctica is occurring and how soil communities and processes are influenced by these expanding plant communities. Through this work the research team, will also be intensively training undergraduate and graduate students, including training of students from underrepresented groups and collaborative training of students from Chile and the US. Additionally, the research groups will continue their focus on scientific outreach with K-12 schools and the general public to expand awareness of the effects of climate change in Antarctica.<br/><br/>Part II: Technical summary<br/>In this study, the researchers will use surveys across succession sites along the Antarctic Peninsula and Scotia Arc as well as a manipulative field experiment at glacier succession sites to test how species-specific plant functional traits impact soil properties and associated microbial and invertebrate communities in a greening Antarctica. In doing so, they will pursue three integrated aims to understand how Antarctic plant functional traits alter their soil environment and soil communities during succession after glacial retreat. AIM 1) Characterize six fundamental plant functional traits (thermal conductivity, water holding capacity, albedo, decomposability, tissue nutrient content, and secondary chemistry) among diverse Antarctica flora; AIM 2) Measure the relative effects of fundamental plant functional traits on soil physical properties and soil biogeochemistry across glacial succession gradients in Antarctica; and AIM 3) Measure the relative effects of fundamental plant functional traits on soil microbial and invertebrate communities across glacial succession gradients in Antarctica. They will explore how early-colonizing plants, especially mosses and lichens, alter soil physical, biogeochemical, and biological components, potentially impacting later patterns of succession. The researhcers will use intensive surveys of plant-soil interactions across succession sites and a manipulative transplant experiment in the South Shetland Islands, Antarctica to address their aims. The investigators will collect data on plant functional traits and their effects on soil physical properties, biogeochemistry, biotic abundance, and microbial metagenomics. The data collected will be the first comprehensive measures of the relative importance of plant functional types during glacial retreat and vegetative expansion from climate change in Antarctica, aiding our understanding of how plant functional group diversity and abundance are changing in a greening Antarctica.<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. | POLYGON((-59.666116 -62.15,-59.5128377 -62.15,-59.3595594 -62.15,-59.2062811 -62.15,-59.0530028 -62.15,-58.8997245 -62.15,-58.7464462 -62.15,-58.5931679 -62.15,-58.4398896 -62.15,-58.2866113 -62.15,-58.133333 -62.15,-58.133333 -62.1731502,-58.133333 -62.1963004,-58.133333 -62.2194506,-58.133333 -62.2426008,-58.133333 -62.265751,-58.133333 -62.2889012,-58.133333 -62.3120514,-58.133333 -62.3352016,-58.133333 -62.3583518,-58.133333 -62.381502,-58.2866113 -62.381502,-58.4398896 -62.381502,-58.5931679 -62.381502,-58.7464462 -62.381502,-58.8997245 -62.381502,-59.0530028 -62.381502,-59.2062811 -62.381502,-59.3595594 -62.381502,-59.5128377 -62.381502,-59.666116 -62.381502,-59.666116 -62.3583518,-59.666116 -62.3352016,-59.666116 -62.3120514,-59.666116 -62.2889012,-59.666116 -62.265751,-59.666116 -62.2426008,-59.666116 -62.2194506,-59.666116 -62.1963004,-59.666116 -62.1731502,-59.666116 -62.15)) | POINT(-58.8997245 -62.265751) | false | false | |||||||||||||
Collaborative Research: Diagnosing the Role of Ocean Eddies in Carbon Cycling from a High-resolution Data Assimilating Ocean Biogeochemical Model
|
2149500 |
2022-03-14 | Williams, Nancy; Chambers, Don; Tamsitt, Veronica | No dataset link provided | The Southern Ocean accounts for ~40% of the total ocean uptake of anthropogenic CO2 despite covering only 20% of the global ocean surface, and is particularly rich in long-lived eddies. These eddies, or large ocean whirlpools which can be observed from space, can alter air-sea fluxes of CO2 in ways that are not yet fully understood. New observations from autonomous platforms measuring ocean carbon content suggest that there is significant heterogeneity in ocean carbon fluxes which can be linked to these dynamic eddy features. Due to computational and time limitations, ocean eddies are not explicitly represented in most climate models, limiting our ability to understand the role eddies play in the ocean carbon cycle. This work will explore the impact of eddies on ocean carbon content and air-sea CO2 fluxes in the Southern Ocean using both model- and observation-based strategies and the findings will improve our understanding of the ocean’s role in the carbon cycle and in global climate. While this work will primarily be focused on the Southern Ocean, the results will be globally applicable. The researchers will also broaden interest in physical and chemical oceanography among middle school-age girls in the University of South Florida’s Oceanography Camp for Girls by augmenting existing lessons with computational methods in oceanography. This project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a “Model STEM Program for Women and Girls” focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography. | POLYGON((-180 -30,-144 -30,-108 -30,-72 -30,-36 -30,0 -30,36 -30,72 -30,108 -30,144 -30,180 -30,180 -36,180 -42,180 -48,180 -54,180 -60,180 -66,180 -72,180 -78,180 -84,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84,-180 -78,-180 -72,-180 -66,-180 -60,-180 -54,-180 -48,-180 -42,-180 -36,-180 -30)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Diagnosing the role of ocean eddies in carbon cycling from a high- resolution data assimilating ocean biogeochemical model
|
2149501 |
2022-03-04 | Mazloff, Matthew | No dataset link provided | This project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a “Model STEM Program for Women and Girls” focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Biological and Physical Drivers of Oxygen Saturation and Net Community Production Variability along the Western Antarctic Peninsula
|
1643534 |
2022-03-03 | Cassar, Nicolas |
|
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 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. | 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)) | POINT(-69.5 -67.5) | false | false | |||||||||||||
Linking Antarctic Cold Desert Groundwater to Thermokarst & Chemical Weathering in Partnership with the Geoscience UAV Academy
|
1847067 |
2021-12-24 | Levy, Joseph |
|
Antarctic groundwater drives the regional carbon cycle, accelerates permafrost thaw, and shapes Antarctic climate response. However, groundwater extent, movement, and processes on a continent virtually locked in ice are poorly understood. The proposed work investigates the interplay between groundwater, sediment, and ice in Antarctica’s cold desert landscapes to determine when, where, and why Antarctic groundwater is flowing, and how quickly it will switch Antarctic frozen deserts from dry and stable to wet and disintegrating. Little is known about the extent, chemistry, and duration of groundwater in Antarctic seasonal wetlands. Mapping the changing extent of Antarctic wetlands requires the ability to measure soil moisture rapidly and repeatedly and over large areas. Changing groundwater extent will be captured through an unmanned aerial vehicle (UAV)-based mapping approach. The project integrates a diverse range of sensors with new UAV technologies to provide a higher-resolution and more frequent assessment of Antarctic groundwater extent and composition than can be accomplished using satellite observations alone. To complement the research objectives, the PI will develop a new UAV summer field school, the Geosciences UAV Academy, focused on training undergraduate-level UAV pilots in conducting novel Earth science research using cutting edge imaging tools. The integration of research and technology will prepare students for careers in burgeoning UAV-related industries and research. The project will deliver new UAV tools and workflows for soil moisture mapping relevant to arid regions common not just to Antarctica but to temperate desert and dryland systems and will train student research pilots to tackle next generation airborne challenges. Water tracks are the basic hydrological unit that currently feeds the rapidly-changing polar and permafrost wetlands in the Antarctic McMurdo Dry Valleys (MDV). Despite the importance of water tracks in the MDV hydrologic cycle and their influence on biogeochemistry, little is known about how these water tracks control the unique brine processes operating in Antarctic ice-free areas. Both groundwater availability and geochemistry shape Antarctic microbial communities, connecting soil geology and hydrology to carbon cycling and ecosystem functioning. The objectives of this CAREER proposal are to 1) map water tracks to determine the spatial distribution and seasonal magnitude of groundwater impacts on the MDV near-surface environment to determine how water tracks drive irreversible permafrost thaw, how water tracks enhance chemical weathering and biogeochemical cycling, and how water tracks integrate and accelerate climate feedbacks between terrestrial Antarctic soils and the Southern Ocean; 2) establish a UAV academy training earth sciences students to answer geoscience questions using drone-based platforms and remote sensing techniques; and 3) provide a formative step in the development of the PI as a teacher-scholar. UAV-borne hyperspectral imaging complemented with field soil sampling will determine the aerial extent and timing of inundation, water level, and water budget of representative water tracks in the MDV. Soil moisture will be measured via near-infrared reflectance spectroscopy while bulk chemistry of soils and groundwater will be analyzed via ion chromatography and soil x-ray fluorescence. Sedimentological and hydrological properties (suction/matric potential, hydraulic conductivity, etc.) will be determined via analysis of intact core samples. These data will be used to test competing hypotheses regarding the origin of water track solutions and water movement through seasonal wetlands. The will provide a regional understanding of Antarctic groundwater sources, groundwater flux, and the influence of regional hydrogeology on solute export to the Southern Ocean and on soil/atmosphere linkages in earth’s carbon budget. The UAV school will 1) provide comprehensive instruction at the undergraduate level in both how and why UAVs can be used in geoscience research and learning; and 2) provide a long-term piece of educational infrastructure in the form of an ultimately self-sustaining summer program for undergraduate UAV education. | POLYGON((161 -76,161.35 -76,161.7 -76,162.05 -76,162.4 -76,162.75 -76,163.1 -76,163.45 -76,163.8 -76,164.15 -76,164.5 -76,164.5 -76.2,164.5 -76.4,164.5 -76.6,164.5 -76.8,164.5 -77,164.5 -77.2,164.5 -77.4,164.5 -77.6,164.5 -77.8,164.5 -78,164.15 -78,163.8 -78,163.45 -78,163.1 -78,162.75 -78,162.4 -78,162.05 -78,161.7 -78,161.35 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76)) | POINT(162.75 -77) | false | false | |||||||||||||
Investigating Antarctic Ice Sheet-Ocean-Carbon Cycle Interactions During the Last Deglaciation
|
2103032 |
2021-09-09 | Schmittner, Andreas; Haight, Andrew ; Clark, Peter | No dataset link provided | 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. It is also the largest potential contributor to future sea level rise and a major uncertainty in climate projections. Climate change may trigger instabilities, which may lead to fast and irreversible collapse of parts of the ice sheet. However, very 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. This project investigates Antarctic ice-ocean interactions of the last 20,000 years. A novel numerical climate model will be constructed 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. Paleoclimate data will be synthesized and compared with simulations of the model. The model-data comparison will address 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. This project will test suggestions 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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Antarctica as a Model System for Responses of Terrestrial Carbon Balance to Warming
|
1947562 1643871 |
2021-08-21 | van Gestel, Natasja | No dataset link provided | Responses of the carbon balance of terrestrial ecosystems to warming will feed back to the pace of climate change, but the size and direction of this feedback are poorly constrained. Least known are the effects of warming on carbon losses from soil, and clarifying the major microbial controls is an important research frontier. This study uses a series of experiments and observations to investigate microbial, including autotrophic taxa, and plant controls of net ecosystem productivity in response to warming in intact ecosystems. Field warming is achieved using open-top chambers paired with control plots, arrayed along a productivity gradient. Along this gradient incoming and outgoing carbon fluxes will be measured at the ecosystem-level. The goal is to tie warming-induced shifts in net ecosystem carbon balance to warming effects on soil microbes and plants. The field study will be supplemented with lab temperature incubations. Because soil microbes dominate biogeochemical cycles in Antarctica, a major focus of this study is to determine warming responses of bacteria, fungi and archaea. This is achieved using a cutting-edge stable isotope technique, quantitative stable isotope probing (qSIP) developed by the proposing research team, that can identify the taxa that are active and involved in processing new carbon. This technique can identify individual microbial taxa that are actively participating in biogeochemical cycling of nutrients (through combined use of 18O-water and 13C-bicarbonate) and thus can be distinguished from those that are simply present (cold-preserved). The study further assesses photosynthetic uptake of carbon by the vegetation and their sensitivity to warming. Results will advance research in climate change, plant and soil microbial ecology, and ecosystem modeling. | POLYGON((-65 -64.5,-64.8 -64.5,-64.6 -64.5,-64.4 -64.5,-64.2 -64.5,-64 -64.5,-63.8 -64.5,-63.6 -64.5,-63.4 -64.5,-63.2 -64.5,-63 -64.5,-63 -64.55,-63 -64.6,-63 -64.65,-63 -64.7,-63 -64.75,-63 -64.8,-63 -64.85,-63 -64.9,-63 -64.95,-63 -65,-63.2 -65,-63.4 -65,-63.6 -65,-63.8 -65,-64 -65,-64.2 -65,-64.4 -65,-64.6 -65,-64.8 -65,-65 -65,-65 -64.95,-65 -64.9,-65 -64.85,-65 -64.8,-65 -64.75,-65 -64.7,-65 -64.65,-65 -64.6,-65 -64.55,-65 -64.5)) | POINT(-64 -64.75) | false | false | |||||||||||||
NSFGEO-NERC: Collaborative Research: Accelerating Thwaites Ecosystem Impacts for the Southern Ocean (ARTEMIS)
|
1941304 1941483 1941327 1941292 1941308 |
2021-08-20 | Yager, Patricia; Medeiros, Patricia; Sherrell, Robert; St-Laurent, Pierre; Fitzsimmons, Jessica; Stammerjohn, Sharon | The Amundsen Sea hosts the most productive polynya in all of Antarctica, with its vibrant green waters visible from space, and an atmospheric CO2 uptake density 10x 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 (WAIS). ARTEMIS aims to characterize the climate-sensitive nature of glacial meltwater-driven micronutrient (iron, Fe) contributions driving ecosystem productivity and CO2 uptake in the coastal Antarctic. We propose to integrate observations and ocean modeling of these processes to enhance predictive capabilities. Currently, basal melt resulting from warm deep waters penetrating ice shelf cavities dominates mass losses of WAIS, contributing to sea level rise. These physical melting processes are being studied by the International Thwaites Glacier Collaboration (ITGC). The impact of melting on the marine ecosystem has also been explored, and we know that productivity is due in part to Fe-rich, glacial meltwater-driven outflow. The biogeochemical composition of the outflow from the glaciers surrounding the Amundsen Sea is largely unstudied, however. Improved knowledge would provide keys to understanding meltwater's future impact on the ecosystem. An ongoing field program (TARSAN, part of the ITGC) offers the ideal physical oceanographic framework for our biogeochemical effort. We propose here to collaborate with TARSAN-supported UK scientists, providing value added to both team efforts. ARTEMIS will add shipboard measurements (trace metals, carbonate system, nutrients, organic matter, microorganisms) and biogeochemical sensors on autonomous vehicles to gather critical knowledge needed to understand the impact of the melting WAIS on both the coastal ecosystem and the regional carbon (C) cycle. Driving questions include: 1) what are the fluxes and chemical forms of Fe, C, and microorganisms in the ice shelf outflow? 2) what are the relative contributions to the ouflow from deep water, benthic, and glacial melt sources, and how do these inputs combine to affect the bioavailability of Fe? 3) How are Fe and C compounds modified as the outflow advects along the coastal current and mixes into the bloom region? and 4) what will be the effect of increased glacial melting, changes in the coastal icescape, and declining sea ice on theecosystem of the Amundsen Sea? Such questions fall outside the focus of the ITGC, but are of keen interest to Antarctic Organisms and Ecosystems and Antarctic Integrated System Science programs. | 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)) | POINT(-110 -73) | false | false | ||||||||||||||
Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys
|
1937748 |
2021-06-30 | Sumner, Dawn; Mackey, Tyler |
|
This project focuses on understanding annual changes in microbial life that grows on the bottom of Lake Fryxell, Antarctica. Because of its polar latitude, photosynthesis can only occur during the summer. During summer, photosynthetic bacteria supply communities with energy and oxygen. However, it is unknown how the microbes behave in the dark winter, when observations are not possible. This project will perform laboratory experiments with a cyanobacterial mat grown from Lake Fryxell samples. Once fieldwork is allowed, we will install environmental monitors and light-blocking shades over small parts of the communities in Lake Fryxell. The shades will extend winter conditions into the spring to allow researchers to characterize the winter behavior of the microbial communities. Researchers will measure changes in the water chemistry due to their activities when they first receive light as the shades are removed. Results are expected to provide insights into how organisms interact with and change their environments. The project extends these scientific results to building a better-prepared, more diverse workforce to perform scientific fieldwork. Fieldwork, including diving, will be performed in part by graduate students under the mentorship of world experts in Antarctic field science. In addition, the project will help students and early career scientists learn field skills by building an online “Guide to Thrive.” This web site will compile field tips ranging from basic gear use to advanced environmental protection techniques. Group leaders ranging from undergraduate teaching assistants to Antarctic expedition leaders will be able to choose appropriate components to build tailored guides for their participants to help them thrive in difficult field conditions. The researchers will measure laboratory-based and field-based seasonal metabolic and biogeochemical changes in benthic mats using differential gene expression and geochemical gradients. They will identify seasonal phenotypic differences and ecosystem effects induced by spring oxygen production. To do so, researchers will install environmental sensors and opaque shades over mats at three depths in the lake. The following spring, they will sample shaded and unshaded mats, remove the shades, track changes in pore water O2, H2S, pH, and redox with microelectrodes, and sample mats for transcriptomic analyses at intervals guided by geochemical changes. Pore water will be sampled for nutrient analyses. Field research will be supplemented with: laboratory experiments to refine field techniques (expanded effort due to COVID field restrictions); gene expression data analysis; and integration of results into a seasonal model of productivity and nitrogen cycling in Lake Fryxell. Results will provide insights into several key priorities for NSF, including how biotic, abiotic and environmental components of the benthic mats interact to affect the regional ecosystem. | POINT(163.183333 -77.616667) | POINT(163.183333 -77.616667) | false | false | |||||||||||||
Collaborative Research: Chemoautotrophy in Antarctic Bacterioplankton Communities Supported by the Oxidation of Urea-derived Nitrogen
|
1643345 1643466 |
2020-12-18 | Hollibaugh, James T.; Popp, Brian |
|
The project addressed fundamental questions regarding the role of nitrification (the conversion of ammonium to nitrate by a two-step process involving two different guilds of microorganisms: ammonia- and nitrite-oxidizers) in the Antarctic marine ecosystem. Specifically, the project evaluated the contribution of carbon fixation supported by energy derived from the oxidation of nitrogen compounds (chemoautotrophy) to the overall supply of organic carbon to the food web of the Southern Ocean. Additionally, the project aimed to determine the significance of the contribution of other sources of reduced nitrogen, specifically organic nitrogen and urea, to nitrification because these contributions may not be assessed by standard protocols. <br><br>We quantified the oxidation rates of 15N supplied as ammonium, urea and nitrite, which allowed us to estimate the contribution of urea-derived N and complete nitrification (ammonia to nitrate, N-3 to N+5) to chemoautotrophy in Antarctic coastal waters. We compared these estimates to direct measurements of the incorporation of dissolved inorganic 14C into organic matter in the dark for an independent estimate of chemoautotrophy. We made measurements on samples taken from the major water masses: surface water (~10 m), winter water (35-174 m), circumpolar deep water (175-1000 m) and slope water (>1000 m); on a cruise surveying the continental shelf and slope west of the Antarctic Peninsula in the austral summer of 2018 (LMG18-01). Samples were also taken to measure the concentrations of nitrite, ammonia, urea and polyamines; for qPCR analysis of the abundance of relevant marker genes; and for studies of processes related to the core questions of the study. The project relied on collaboration with the Palmer LTER for ancillary data (bacterioplankton abundance and production, chlorophyll, physical and additional chemical variables). The synergistic activities of this project along with the LTER activities provides a unique opportunity to assess chemoautotrophy in context of the overall ecosystem's dynamics, including both primary and secondary production processes. <br><br>This project resulted in the training of a postdoctoral researcher and provide undergraduate students opportunities to gain hand-on experience with research on microbial geochemistry. This project contributed substantially to understanding an important aspect of nitrogen cycling and bacterioplankton production in the study area. Both PIs participate fully in the education and outreach efforts of the Palmer LTER, including making highlights of the findings available for posting to the LTER project web site, posting material to web sites at their respective departments, and incorporating material from the study in lectures and seminars presented at their respective institutions. | POLYGON((-78.20206667 -64.03195833,-76.785055836 -64.03195833,-75.368045002 -64.03195833,-73.951034168 -64.03195833,-72.534023334 -64.03195833,-71.1170125 -64.03195833,-69.700001666 -64.03195833,-68.282990832 -64.03195833,-66.865979998 -64.03195833,-65.448969164 -64.03195833,-64.03195833 -64.03195833,-64.03195833 -64.554377497,-64.03195833 -65.076796664,-64.03195833 -65.599215831,-64.03195833 -66.121634998,-64.03195833 -66.644054165,-64.03195833 -67.166473332,-64.03195833 -67.688892499,-64.03195833 -68.211311666,-64.03195833 -68.733730833,-64.03195833 -69.25615,-65.448969164 -69.25615,-66.865979998 -69.25615,-68.282990832 -69.25615,-69.700001666 -69.25615,-71.1170125 -69.25615,-72.534023334 -69.25615,-73.951034168 -69.25615,-75.368045002 -69.25615,-76.785055836 -69.25615,-78.20206667 -69.25615,-78.20206667 -68.733730833,-78.20206667 -68.211311666,-78.20206667 -67.688892499,-78.20206667 -67.166473332,-78.20206667 -66.644054165,-78.20206667 -66.121634998,-78.20206667 -65.599215831,-78.20206667 -65.076796664,-78.20206667 -64.554377497,-78.20206667 -64.03195833)) | POINT(-71.1170125 -66.644054165) | false | false | |||||||||||||
Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean
|
1542962 |
2020-09-25 | Anderson, Robert; Fleisher, Martin; Pavia, Frank | General: 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 that regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. This project was designed 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 the 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 was to 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 was expected to 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. Technical: The project added a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that collected sediment cores at locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170°W. The goal was 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. We proposed to compare the radiocarbon age of foraminifera that inhabited the surface ocean with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms would have been 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 was expected that surface and deep-dwelling foraminifera would 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 outcrop at the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work was 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 Antarctica. Unfortunately, the cores were shipped to the core repository in a horizontal orientation and there was sufficient distortion of the sediment that the radiocarbon ages of benthic foraminifera were uninterpretable. Therefore, we report only the radiocarbon dates for planktonic foraminifera as well as the total counts of elemental relative abundance from X-ray Fluorescence analysis of the cores. In addition, we used the expedition as an opportunity to collect water samples from which dissolved concentrations of long-lived isotope of thorium and protactinium were determined. Results from those analyses showed that lateral transport by isopycnal mixing dominates the supply of Pa to the Southern Ocean. We have also developed a new algorithm to correct for supply of Th by isopycnal mixing and thereby derive estimates of dust flux to the Southern Ocean. | 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)) | POINT(-170 -60.6) | false | false | ||||||||||||||
Collaborative Research: Antarctic Airborne ElectroMagnetics (ANTAEM) - Revealing Subsurface Water in Coastal Antarctica
|
1644187 |
2020-09-13 | Tulaczyk, Slawek; Mikucki, Jill |
|
In Antarctica, millions of years of freezing have led to the development of hundreds of meters of thick permafrost (i.e., frozen ground). Recent research demonstrated that this slow freezing has trapped and concentrated water into local and regional briny aquifers, many times more salty than seawater. Because salt depresses the freezing point of water, these saline brines are able to persist as liquid water at temperatures well below the normal freezing point of freshwater. Such unusual groundwater systems may support microbial life, supply nutrients to coastal ocean and ice-covered lakes, and influence motion of glaciers. These briny aquifers also represent potential terrestrial analogs for deep life habitats on other planets, such as Mars, and provide a testing ground for the search for extraterrestrial water. Whereas much effort has been invested in understanding the physics, chemistry, and biology of surface and near-surface waters in cold polar regions, it has been comparably difficult to investigate deep subsurface aquifers in such settings. Airborne ElectroMagnetics (AEM) subsurface imaging provides an efficient way for mapping salty groundwater. An international collaboration with the University of Aarhus in Denmark will enable knowledge and skill transfer in AEM techniques that will enhance US polar research capabilities and provide US undergraduates and graduate students with unique training experiences. This project will survey over 1000 km2 of ocean and land near McMurdo Station in Antarctica, and will reveal if cold polar deserts hide a subsurface pool of liquid water. This will have significant implications for understanding cold polar glaciers, ice-covered lakes, frozen ground, and polar microbiology as well as for predictions of their response to future change. Improvements in permafrost mapping techniques and understanding of permafrost and of underlying groundwaters will benefit human use of high polar regions in the Antarctic and the Arctic.<br/><br/>The project will provide the first integrative system-scale overview of subsurface water distribution and hydrological connectivity in a partly ice-free coastal region of Antarctica, the McMurdo Dry Valleys. Liquid water is relatively scarce in this environment but plays an outsized role by influencing, and integrating, biological, biogeochemical, glaciological, and geological processes. Whereas surface hydrology and its role in ecosystem processes has been thoroughly studied over the last several decades, it has been difficult to map out and characterize subsurface water reservoirs and to understand their interactions with regional lakes, glaciers, and coastal waters. The proposed project builds on the "proof-of-concept" use of AEM technology in 2011. Improvements in sensor and data processing capabilities will result in about double the depth of penetration of the subsurface during the new data collection when compared to the 2011 proof-of-concept survey, which reached depths of 300-400m. The first field season will focus on collecting deep soundings with a ground-based system in key locations where: (i) independent constraints on subsurface structure exist from past drilling projects, and (ii) the 2011 resistivity dataset indicates the need for deeper penetration and high signal-to-noise ratios achievable only with a ground-based system. The regional airborne survey will take place during the second field season and will yield subsurface electrical resistivity data from across several valleys of different sizes and different ice cover fractions. | POLYGON((161 -76.9,161.75 -76.9,162.5 -76.9,163.25 -76.9,164 -76.9,164.75 -76.9,165.5 -76.9,166.25 -76.9,167 -76.9,167.75 -76.9,168.5 -76.9,168.5 -77.04,168.5 -77.18,168.5 -77.32,168.5 -77.46,168.5 -77.6,168.5 -77.74,168.5 -77.88,168.5 -78.02,168.5 -78.16,168.5 -78.3,167.75 -78.3,167 -78.3,166.25 -78.3,165.5 -78.3,164.75 -78.3,164 -78.3,163.25 -78.3,162.5 -78.3,161.75 -78.3,161 -78.3,161 -78.16,161 -78.02,161 -77.88,161 -77.74,161 -77.6,161 -77.46,161 -77.32,161 -77.18,161 -77.04,161 -76.9)) | POINT(164.75 -77.6) | false | false | |||||||||||||
Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean
|
1543450 |
2020-08-01 | Countway, Peter | The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\DMS production. The project examined the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project interacted with elementary students in Maine and brought undergraduate students to Bigelow Laboratory. The project also engaged with a science writer and illustrator who joined the team in Palmer Station in 2018. Many posts are available at xxx The project is examining (1) the extent to which the cycling of DMSP in southern ocean waters influenced the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influenced the magnitude and rates of DMSP cycling; we are awaiting results on (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to field experimental additions of DMSP; and, this year (2020-21), we will synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work was accomplished by conducting continuous growth experiments with DMSP-amended natural samples of different microbial communities present in summer (2016-17) and fall (2018) at Palmer Station, WAP. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis in the coming year (2020-21). | POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63)) | POINT(-64.5 -64.5) | false | false | ||||||||||||||
Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments
|
1543537 1543347 1543453 1543396 1543405 1543441 |
2020-07-16 | Rosenheim, Brad; Fricker, Helen; Priscu, John; Leventer, Amy; Dore, John; Lyons, W. Berry; Christner, Brent | The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website.<br/><br/>Subglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication. | POLYGON((-163.611 -84.33543,-162.200034 -84.33543,-160.789068 -84.33543,-159.378102 -84.33543,-157.967136 -84.33543,-156.55617 -84.33543,-155.145204 -84.33543,-153.734238 -84.33543,-152.323272 -84.33543,-150.912306 -84.33543,-149.50134 -84.33543,-149.50134 -84.3659157,-149.50134 -84.3964014,-149.50134 -84.4268871,-149.50134 -84.4573728,-149.50134 -84.4878585,-149.50134 -84.5183442,-149.50134 -84.5488299,-149.50134 -84.5793156,-149.50134 -84.6098013,-149.50134 -84.640287,-150.912306 -84.640287,-152.323272 -84.640287,-153.734238 -84.640287,-155.145204 -84.640287,-156.55617 -84.640287,-157.967136 -84.640287,-159.378102 -84.640287,-160.789068 -84.640287,-162.200034 -84.640287,-163.611 -84.640287,-163.611 -84.6098013,-163.611 -84.5793156,-163.611 -84.5488299,-163.611 -84.5183442,-163.611 -84.4878585,-163.611 -84.4573728,-163.611 -84.4268871,-163.611 -84.3964014,-163.611 -84.3659157,-163.611 -84.33543)) | POINT(-156.55617 -84.4878585) | false | false | ||||||||||||||
Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle
|
1543483 |
2020-06-22 | Sedwick, Peter |
|
The waters of the Ross Sea continental shelf are among the most productive in the Southern Ocean, and may comprise a significant regional oceanic sink for atmospheric carbon dioxide. In this region, primary production can be limited by the supply of dissolved iron to surface waters during the growing season. Water-column observations, sampling and measurements are to be carried out in the late autumn-early winter time frame on the Ross Sea continental shelf and coastal polynyas (Terra Nova Bay and Ross Ice Shelf polynyas), in order to better understand what drives the biogeochemical redistribution of micronutrient iron species during the onset of convective mixing and sea-ice formation at this time of year, thereby setting conditions for primary production during the following spring. The spectacular field setting and remote, hostile conditions that accompany the proposed field study present exciting possibilities for STEM education and training. At the K-12 level, the project seeks to support the development of educational outreach materials targeting elementary and middle school students, pre-service science teachers, and in-service science teachers. | POLYGON((-180 -66,-179.5 -66,-179 -66,-178.5 -66,-178 -66,-177.5 -66,-177 -66,-176.5 -66,-176 -66,-175.5 -66,-175 -66,-175 -67.2,-175 -68.4,-175 -69.6,-175 -70.8,-175 -72,-175 -73.2,-175 -74.4,-175 -75.6,-175 -76.8,-175 -78,-175.5 -78,-176 -78,-176.5 -78,-177 -78,-177.5 -78,-178 -78,-178.5 -78,-179 -78,-179.5 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.8,165 -75.6,165 -74.4,165 -73.2,165 -72,165 -70.8,165 -69.6,165 -68.4,165 -67.2,165 -66,166.5 -66,168 -66,169.5 -66,171 -66,172.5 -66,174 -66,175.5 -66,177 -66,178.5 -66,-180 -66)) | POINT(175 -72) | false | false | |||||||||||||
Organic carbon oxidation and iron remobilization by West Antarctic shelf sediments
|
1551195 |
2020-06-16 | Burdige, David; Christensen, John |
|
This project investigated the distribution of dissolved and solid phase iron in sediments along the western edge of the Antarctic Peninsula (i.e., the West Antarctic Shelf), as well as the biogeochemical processes occurring in these sediments that exert a major control on sediment iron distributions. In many coastal and continental margin regions, including those along the west side of the Antarctic Peninsula, sediments appear to represent a potentially important, but poorly quantified, source of iron to the overlying water column to support primary productivity. Sediment concentrations of iron are high (relative to those in seawater), and a number of different processes in the sediments may allow iron to “leak” from the sediments to the overlying waters, which could then support productivity driven by this “recycled” iron. | POLYGON((-71 -64,-70.1 -64,-69.2 -64,-68.3 -64,-67.4 -64,-66.5 -64,-65.6 -64,-64.7 -64,-63.8 -64,-62.9 -64,-62 -64,-62 -64.4,-62 -64.8,-62 -65.2,-62 -65.6,-62 -66,-62 -66.4,-62 -66.8,-62 -67.2,-62 -67.6,-62 -68,-62.9 -68,-63.8 -68,-64.7 -68,-65.6 -68,-66.5 -68,-67.4 -68,-68.3 -68,-69.2 -68,-70.1 -68,-71 -68,-71 -67.6,-71 -67.2,-71 -66.8,-71 -66.4,-71 -66,-71 -65.6,-71 -65.2,-71 -64.8,-71 -64.4,-71 -64)) | POINT(-66.5 -66) | false | false | |||||||||||||
A High Resolution Atmospheric Methane Record from the South Pole Ice Core
|
1643722 |
2020-06-02 | Brook, Edward J. |
|
This award supports a project to measure the concentration of the gas methane in air trapped in an ice core collected from the South Pole. The data will provide an age scale (age as a function of depth) by matching the South Pole methane changes with similar data from other ice cores for which the age vs. depth relationship is well known. The ages provided will allow all other gas measurements made on the South Pole core (by the PI and other NSF supported investigators) to be interpreted accurately as a function of time. This is critical because a major goal of the South Pole coring project is to understand the history of rare gases in the atmosphere like carbon monoxide, carbon dioxide, ethane, propane, methyl chloride, and methyl bromide. Relatively little is known about what controls these gases in the atmosphere despite their importance to atmospheric chemistry and climate. Undergraduate assistants will work on the project and be introduced to independent research through their work. The PI will continue visits to local middle schools to introduce students to polar science, and other outreach activities (e.g. laboratory tours, talks to local civic or professional organizations) as part of the project. <br/><br/>Methane concentrations from a major portion (2 depth intervals, excluding the brittle ice-zone which is being measured at Penn State University) of the new South Pole ice core will be used to create a gas chronology by matching the new South Pole ice core record with that from the well-dated WAIS Divide ice core record. In combination with measurements made at Penn State, this will provide gas dating for the entire 50,000-year record. Correlation will be made using a simple but powerful mid-point method that has been previously demonstrated, and other methods of matching records will be explored. The intellectual merit of this work is that the gas chronology will be a fundamental component of this ice core project, and will be used by the PI and other investigators for dating records of atmospheric composition, and determining the gas age-ice age difference independently of glaciological models, which will constrain processes that affected firn densification in the past. The methane data will also provide direct stratigraphic markers of important perturbations to global biogeochemical cycles (e.g., rapid methane variations synchronous with abrupt warming and cooling in the Northern Hemisphere) that will tie other ice core gas records directly to those perturbations. A record of the total air content will also be produced as a by-product of the methane measurements and will contribute to understanding of this parameter. The broader impacts include that the work will provide a fundamental data set for the South Pole ice core project and the age scale (or variants of it) will be used by all other investigators working on gas records from the core. The project will employ an undergraduate assistant(s) in both years who will conduct an undergraduate research project which will be part of the student's senior thesis or other research paper. The project will also offer at least one research position for the Oregon State University Summer REU site program. Visits to local middle schools, and other outreach activities (e.g. laboratory tours, talks to local civic or professional organizations) will also be part of the project. | POINT(0 -90) | POINT(0 -90) | false | false | |||||||||||||
Carbonyl Sulfide, Methyl Chloride, and Methyl Bromide Measurements in the New Intermediate-depth South Pole Ice Core
|
1443470 |
2020-03-26 | Aydin, Murat |
|
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.<br/><br/>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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay
|
1643684 1644073 |
2019-08-08 | DiTullio, Giacomo; Lee, Peter |
|
Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations. <br/><br/>The study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems. | POLYGON((-180 -72,-173.6 -72,-167.2 -72,-160.8 -72,-154.4 -72,-148 -72,-141.6 -72,-135.2 -72,-128.8 -72,-122.4 -72,-116 -72,-116 -72.7,-116 -73.4,-116 -74.1,-116 -74.8,-116 -75.5,-116 -76.2,-116 -76.9,-116 -77.6,-116 -78.3,-116 -79,-122.4 -79,-128.8 -79,-135.2 -79,-141.6 -79,-148 -79,-154.4 -79,-160.8 -79,-167.2 -79,-173.6 -79,180 -79,178 -79,176 -79,174 -79,172 -79,170 -79,168 -79,166 -79,164 -79,162 -79,160 -79,160 -78.3,160 -77.6,160 -76.9,160 -76.2,160 -75.5,160 -74.8,160 -74.1,160 -73.4,160 -72.7,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,172 -72,174 -72,176 -72,178 -72,-180 -72)) | POINT(-158 -75.5) | false | false | |||||||||||||
High-resolution, Assemblage-specific Records of Diatom-bound N Isotopes from the Indian Sector of the Antarctic Ocean
|
1401489 |
2019-08-08 | Sigman, Daniel | ABSTRACT<br/>Intellectual Merit:<br/>The high concentration of the major nutrients nitrate and phosphate is a fundamental characteristic of the Antarctic Zone in the Southern Ocean and is central to its role in global ocean fertility and the global carbon cycle. The isotopic composition of diatom-bound organic nitrogen is one of the best hopes for reconstructing the nutrient status of polar surface waters over glacial cycles, which in turn may hold the explanation for the decline in atmospheric carbon dioxide during ice ages. The PIs propose to generate detailed diatom-bound nitrogen isotope (δ15Ndb) records from high sedimentation rate cores from the Kerguelen Plateau. Because the cores were collected at relatively shallow seafloor depths, they have adequate planktonic and benthic foraminifera to develop accurate age models. The resulting data could be compared with climate records from Antarctic ice cores and other archives to investigate climate-related changes, including the major steps into and out of ice ages and the millennial-scale events that occur during ice ages and at their ends. The records generated in this project will provide a critical test of hypotheses for the cause of lower ice age CO2.<br/><br/>Broader impacts:<br/>This study will contribute to the goal of understanding ice ages and past CO2 changes, which both have broad implications for future climate. Undergraduates will undertake summer internships, with the possibility of extending their work into junior year projects and senior theses. In addition, the PI will lead modules for two Princeton programs for middle school teachers and will host a teacher for a six-week summer research project. | POLYGON((-180 -45,-144 -45,-108 -45,-72 -45,-36 -45,0 -45,36 -45,72 -45,108 -45,144 -45,180 -45,180 -47.5,180 -50,180 -52.5,180 -55,180 -57.5,180 -60,180 -62.5,180 -65,180 -67.5,180 -70,144 -70,108 -70,72 -70,36 -70,0 -70,-36 -70,-72 -70,-108 -70,-144 -70,-180 -70,-180 -67.5,-180 -65,-180 -62.5,-180 -60,-180 -57.5,-180 -55,-180 -52.5,-180 -50,-180 -47.5,-180 -45)) | POINT(0 -89.999) | false | false | ||||||||||||||
Spring Blooms of Sea Ice Algae Along the Western Antarctic Peninsula: Effects of Warming and Freshening on Cell Physiology and Biogeochemical Cycles.
|
1744645 |
2019-07-23 | Young, Jodi; Deming, Jody |
|
Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. <br/><br/><br/>There is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula.<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. | POLYGON((-64.4 -64.2,-64.38 -64.2,-64.36 -64.2,-64.34 -64.2,-64.32 -64.2,-64.3 -64.2,-64.28 -64.2,-64.26 -64.2,-64.24 -64.2,-64.22 -64.2,-64.2 -64.2,-64.2 -64.26,-64.2 -64.32,-64.2 -64.38,-64.2 -64.44,-64.2 -64.5,-64.2 -64.56,-64.2 -64.62,-64.2 -64.68,-64.2 -64.74,-64.2 -64.8,-64.22 -64.8,-64.24 -64.8,-64.26 -64.8,-64.28 -64.8,-64.3 -64.8,-64.32 -64.8,-64.34 -64.8,-64.36 -64.8,-64.38 -64.8,-64.4 -64.8,-64.4 -64.74,-64.4 -64.68,-64.4 -64.62,-64.4 -64.56,-64.4 -64.5,-64.4 -64.44,-64.4 -64.38,-64.4 -64.32,-64.4 -64.26,-64.4 -64.2)) | POINT(-64.3 -64.5) | false | false | |||||||||||||
COLLABORATIVE RESEARCH: Remote Characterization of Microbial Mats in Taylor Valley, Antarctica, through In Situ Sampling and Spectral Validation
|
1744849 1744785 1745053 |
2019-07-03 | Salvatore, Mark; Barrett, John; Sokol, Eric |
|
Microbial mats are found throughout the McMurdo Dry Valleys where summer snowmelt provides liquid water that allows these mats to flourish. Researchers have long studied the environmental conditions microbial mats need to grow. Despite these efforts, it has been difficult to develop a broad picture of these unique ecosystems. Recent advances in satellite technology now provide researchers an exciting new tool to study these special Antarctic ecosystems from space using the unique spectral signatures associated with microbial mats. This new technology not only offers the promise that microbial mats can be mapped and studied from space, this research will also help protect these delicate environments from potentially harmful human impacts that can occur when studying them from the ground. This project will use satellite imagery and spectroscopic techniques to identify and map microbial mat communities and relate their properties and distributions to both field and lab-based measurements. This research provides an exciting new tool to help document and understand the distribution of a major component of the Antarctic ecosystem in the McMurdo Dry Valleys. The goal of this project is to establish quantitative relationships between spectral signatures derived from orbit and the physiological status and biogeochemical properties of microbial mat communities in Taylor Valley, Antarctica, as measured by field and laboratory analyses on collected samples. The goal will be met by (1) refining atmospheric correction techniques using in situ radiometric rectification to derive accurate surface spectra; (2) collecting multispectral orbital images concurrent with in situ sampling and spectral measurements in the field to ensure temporal comparability; (3) measuring sediment, water, and microbial mat samples for organic and inorganic carbon content, essential biogeochemical nutrients, and chlorophyll-a to determine relevant mat characteristics; and (4) quantitatively associating these laboratory-derived characteristics with field-derived and orbital spectral signatures and parameters. The result of this work will be a more robust quantitative link between the distribution of microbial mat communities and their biogeochemical properties to landscape-scale spectral signatures. 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. | POLYGON((162.92 -77.56,162.971 -77.56,163.022 -77.56,163.073 -77.56,163.124 -77.56,163.175 -77.56,163.226 -77.56,163.277 -77.56,163.328 -77.56,163.379 -77.56,163.43 -77.56,163.43 -77.571,163.43 -77.582,163.43 -77.593,163.43 -77.604,163.43 -77.615,163.43 -77.626,163.43 -77.637,163.43 -77.648,163.43 -77.659,163.43 -77.67,163.379 -77.67,163.328 -77.67,163.277 -77.67,163.226 -77.67,163.175 -77.67,163.124 -77.67,163.073 -77.67,163.022 -77.67,162.971 -77.67,162.92 -77.67,162.92 -77.659,162.92 -77.648,162.92 -77.637,162.92 -77.626,162.92 -77.615,162.92 -77.604,162.92 -77.593,162.92 -77.582,162.92 -77.571,162.92 -77.56)) | POINT(163.175 -77.615) | false | false | |||||||||||||
Collaborative research: Antarctic diatom proteorhodopsins: Characterization and a potential role in the iron-limitation response
|
1745036 1744760 |
2019-06-16 | Marchetti, Adrian; Septer, Alecia; Hopkinson, Brian |
|
Proteorhodopsins (PR) are retinal-binding membrane proteins that can act as light-driven proton pumps to generate energy that can be used for metabolism and growth. The discovery of PRs in many diverse marine prokaryotic microbes has initiated extensive investigations into their distributions and functional roles. Recently, a rhodopsin-like gene of the proton-pumping variety was identified in diatoms thus revealing their presence within obligate marine eukaryotic photoautotrophs. Since this time, PRs have been identified in a number of diatom isolates although there appears to be a much higher frequency of PR in diatoms residing in cold, iron-limited regions of the ocean, particularly in the Southern Ocean (SO). PR is especially suited for use in SO phytoplankton since unlike conventional photosynthesis, it uses no iron and its reaction rate is insensitive to temperature. The overall objective of our proposed project is to characterize Antarctic diatom-PR and determine its role in the adaptation of SO diatoms to the prevailing conditions of low iron concentrations and extremely low temperatures. Our research objectives will be achieved through a combination of molecular, biochemical and physiological measurements in diatom isolates recently obtained from the Western Antarctic Peninsula region. We will determine the proton-pumping characteristics and pumping rates of PR as a function of light intensity and wavelength, the resultant PR-linked intracellular ATP production rates, and the cellular localization of the protein. We will examine under which environmental conditions Antarctic diatom-PR is most highly expressed and construct a cellular energy budget that includes diatom-PR when grown under these different growth conditions. Estimates of the energy flux generated by PR in PR-containing diatoms will be compared to total energy generation by the photosynthetic light reactions and metabolically coupled respiration rates. Finally, we will compare the characteristics and gene expression of diatom-PR in Antarctic diatoms to PR-containing diatoms isolated from temperate regions in order to investigate if there is a preferential dependence on energy production through diatom-PR in diatoms residing in cold, iron-limited regions of the ocean. | POLYGON((-77 -61,-75.2 -61,-73.4 -61,-71.6 -61,-69.8 -61,-68 -61,-66.2 -61,-64.4 -61,-62.6 -61,-60.8 -61,-59 -61,-59 -62.1,-59 -63.2,-59 -64.3,-59 -65.4,-59 -66.5,-59 -67.6,-59 -68.7,-59 -69.8,-59 -70.9,-59 -72,-60.8 -72,-62.6 -72,-64.4 -72,-66.2 -72,-68 -72,-69.8 -72,-71.6 -72,-73.4 -72,-75.2 -72,-77 -72,-77 -70.9,-77 -69.8,-77 -68.7,-77 -67.6,-77 -66.5,-77 -65.4,-77 -64.3,-77 -63.2,-77 -62.1,-77 -61)) | POINT(-68 -66.5) | false | false | |||||||||||||
LTER: Ecosystem Response to Amplified Landscape Connectivity in the McMurdo Dry Valleys, Antarctica
|
1637708 |
2019-05-31 | Gooseff, Michael N.; Takacs-Vesbach, Cristina; Howkins, Adrian; McKnight, Diane; Doran, Peter; Adams, Byron; Barrett, John; Morgan-Kiss, Rachael; Priscu, John |
|
The McMurdo Dry Valleys, Antarctica, are a mosaic of terrestrial and aquatic ecosystems in a cold desert. The McMurdo Long Term Ecological Research (LTER) project has been observing these ecosystems since 1993 and this award will support key long-term measurements, manipulation experiments, synthesis, and modeling to test current theories on ecosystem structure and function. Data collection is focused on meteorology and physical and biological dimensions of soils, streams, lakes, glaciers, and permafrost. The long-term measurements show that biological communities have adapted to the seasonally cold, dark, and arid conditions that prevail for all but a short period in the austral summer. Physical (climate and geological) drivers impart a dynamic connectivity among portions of the Dry Valley landscape over seasonal to millennial time scales. For instance, lakes and soils have been connected through cycles of lake-level rise and fall over the past 20,000 years while streams connect glaciers to lakes over seasonal time scales. Overlaid upon this physical system are biotic communities that are structured by the environment and by the movement of individual organisms within and between the glaciers, streams, lakes, and soils. The new work to be conducted at the McMurdo LTER site will explore how the layers of connectivity in the McMurdo Dry Valleys influence ecosystem structure and function. This project will test the hypothesis that increased ecological connectivity following enhanced melt conditions within the McMurdo Dry Valleys ecosystem will amplify exchange of biota, energy, and matter, homogenizing ecosystem structure and functioning. This hypothesis will be tested with new and continuing experiments that examine: 1) how climate variation alters connectivity among landscape units, and 2) how biota are connected across a heterogeneous landscape using state-of-the-science tools and methods including automated sensor networks, analysis of seasonal satellite imagery, biogeochemical analyses, and next-generation sequencing. McMurdo LTER education programs and outreach activities will be continued, and expanded with new programs associated with the 200th anniversary of the first recorded sightings of Antarctica. These activities will advance societal understanding of how polar ecosystems respond to change. McMurdo 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 lead the development of international environmental stewardship protocols for human activities in the region. | POLYGON((160 -77.25,160.5 -77.25,161 -77.25,161.5 -77.25,162 -77.25,162.5 -77.25,163 -77.25,163.5 -77.25,164 -77.25,164.5 -77.25,165 -77.25,165 -77.375,165 -77.5,165 -77.625,165 -77.75,165 -77.875,165 -78,165 -78.125,165 -78.25,165 -78.375,165 -78.5,164.5 -78.5,164 -78.5,163.5 -78.5,163 -78.5,162.5 -78.5,162 -78.5,161.5 -78.5,161 -78.5,160.5 -78.5,160 -78.5,160 -78.375,160 -78.25,160 -78.125,160 -78,160 -77.875,160 -77.75,160 -77.625,160 -77.5,160 -77.375,160 -77.25)) | POINT(162.5 -77.875) | false | false | |||||||||||||
EAGER: Elucidating the Antarctic Methane Cycle at the Cinder Cones Reducing Habitat.
|
1642570 |
2019-05-24 | Thurber, Andrew |
|
Methane is a potent greenhouse gas that is naturally emitted into the oceans by geologic seeps and microbial production. Based on studies of persistent deep-sea seeps at mid- and northern latitudes, researchers have learned that bacteria and archaea can create a "sediment filter" that oxidizes methane prior to its release. Antarctica is thought to contain large reservoirs of organic carbon buried beneath its ice which could a quantity of methane equivalent to all of the permafrost in the Arctic and yet we know almost nothing about the methane oxidizing microbes in this region. How these microbial communities develop and potentially respond to fluctuations in methane levels is an under-explored avenue of research. A bacterial mat was recently discovered at 78 degrees south, suggesting the possible presence of a methane seep, and associated microbial communities. This project will explore this environment in detail to assess the levels and origin of methane, and the nature of the microbial ecosystem present. <br/> <br/>An expansive bacterial mat appeared and/or was discovered at 78 degrees south in 2011. This site, near McMurdo Station Antarctica, has been visited since the mid-1960s, but this mat was not observed until 2011. The finding of this site provides an unusual opportunity to study an Antarctic marine benthic habitat with active methane cycling and to examine the dynamics of recruitment and community succession of seep fauna including bacteria, archaea, protists and metazoans. This project will collect the necessary baseline data to facilitate further studies of Antarctic methane cycling. The concentration and source of methane will be determined at this site and at potentially analogous sites in McMurdo Sound. In addition to biogeochemical characterization of the sites, molecular analysis of the microbial community will quantify the time scales on which bacteria and archaea respond to methane input and provide information on rates of community development and succession in the Southern Ocean. Project activities will facilitate the training of at least one graduate student and results will be shared at both local and international levels. A female graduate student will be mentored as part of this project and data collected will form part of her dissertation. Lectures will be given in K-12 classrooms in Oregon to excite students about polar science. National and international audiences will be reached through blogs and presentations at a scientific conference. The PI's previous blogs have been used by K-12 classrooms as part of their lesson plans and followed in over 65 countries.<br/> | POINT(166.666 -77.8) | POINT(166.666 -77.8) | false | false | |||||||||||||
Iron and Light Limitation in Ecologically Important Polar Diatoms: Comparative Transcriptomics and Development of Molecular Indicators
|
1341479 |
2019-03-11 | Marchetti, Adrian |
|
The Southern Ocean surrounding Antarctica is changing rapidly in response to Earth's warming climate. These changes will undoubtedly influence communities of primary producers (the organisms at the base of the food chain, particularly plant-like organisms using sunlight for energy) by altering conditions that influence their growth and composition. Because primary producers such as phytoplankton play an important role in global biogeochemical cycling, it is essential to understand how they will respond to changes in their environment. The growth of phytoplankton in certain regions of the Southern Ocean is constrained by steep gradients in chemical and physical properties that vary in both space and time. Light and iron have been identified as key variables influencing phytoplankton abundance and distribution within Antarctic waters. Microscopic algae known as diatoms are dominant members of the phytoplankton and sea ice communities, accounting for significant proportions of primary production. The overall objective of this project is to identify the molecular bases for the physiological responses of polar diatoms to varying light and iron conditions. The project should provide a means of evaluating the extent these factors regulate diatom growth and influence net community productivity in Antarctic waters. Although numerous studies have investigated how polar diatoms are affected by varying light and iron, the cellular mechanisms leading to their distinct physiological responses remain unknown. We observed several growth responses, but a majority of polar diatom growth rates and photophysiology did not appear to be co-limited by iron and light limitation. Using comparative transcriptomics, we have examined the expression patterns of key genes and metabolic pathways in several ecologically important polar diatoms isolated from Antarctic waters and grown under varying iron and irradiance conditions. In addition, molecular indicators for iron and light limitation will be developed within these polar diatoms through the identification of iron- and light-responsive genes -- the expression patterns of which can be used to determine their physiological status. Upon verification in laboratory cultures, these indicators will be utilized by way of metatranscriptomic sequencing to examine iron and light limitation in natural diatom assemblages collected along environmental gradients in Western Antarctic Peninsula waters. In order to fully understand the role phytoplankton play in Southern Ocean biogeochemical cycles, dependable methods that provide a means of elucidating the physiological status of phytoplankton at any given time and location are essential. | POLYGON((-72.8 -48,-67.12 -48,-61.44 -48,-55.76 -48,-50.08 -48,-44.4 -48,-38.72 -48,-33.04 -48,-27.36 -48,-21.68 -48,-16 -48,-16 -50.02,-16 -52.04,-16 -54.06,-16 -56.08,-16 -58.1,-16 -60.12,-16 -62.14,-16 -64.16,-16 -66.18,-16 -68.2,-21.68 -68.2,-27.36 -68.2,-33.04 -68.2,-38.72 -68.2,-44.4 -68.2,-50.08 -68.2,-55.76 -68.2,-61.44 -68.2,-67.12 -68.2,-72.8 -68.2,-72.8 -66.18,-72.8 -64.16,-72.8 -62.14,-72.8 -60.12,-72.8 -58.1,-72.8 -56.08,-72.8 -54.06,-72.8 -52.04,-72.8 -50.02,-72.8 -48)) | POINT(-44.4 -58.1) | false | false | |||||||||||||
Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)
|
1443705 1443680 1443733 |
2019-02-13 | Winsor, Peter; Truffer, Martin; Smith, Craig; Powell, Brian; Merrifield, Mark; Vernet, Maria; Kohut, Josh | Marine communities along the western Antarctic Peninsula are highly productive ecosystems which support a diverse assemblage of charismatic animals such as penguins, seals, and whales as well as commercial fisheries such as that on Antarctic krill. Fjords (long, narrow, deep inlets of the sea between high cliffs) along the central coast of the Peninsula appear to be intense, potentially climate sensitive, hotspots of biological production and biodiversity, yet the structure and dynamics of these fjord ecosystems are very poorly understood. Because of this intense biological activity and the charismatic fauna it supports, these fjords are also major destinations for a large Antarctic tourism industry. This project is an integrated field and modeling program to evaluate physical oceanographic processes, glacial inputs, water column community dynamics, and seafloor bottom community structure and function in these important yet little understood fjord systems. These Antarctic fjords have characteristics that are substantially different from well-studied Arctic fjords, likely yielding much different responses to climate warming. This project will provide major new insights into the dynamics and climate sensitivity of Antarctic fjord ecosystems, highlighting contrasts with Arctic sub-polar fjords, and potentially transforming our understanding of the ecological role of fjords in the rapidly warming west Antarctic coastal marine landscape. The project will also further the NSF goal of training new generations of scientists, providing scientific training for undergraduate, graduate, and postdoctoral students. This includes the unique educational opportunity for undergraduates to participate in research cruises in Antarctica and the development of a novel summer graduate course on fjord ecosystems. Internet based outreach activities will be enhanced and extended by the participation of a professional photographer who will produce magazine articles, websites, radio broadcasts, and other forms of public outreach on the fascinating Antarctic ecosystem. <br/><br/>This project will involve a 15-month field program to test mechanistic hypotheses concerning oceanographic and glaciological forcing, and phytoplankton and benthic community response in the Antarctic fjords. Those efforts will be followed by a coupled physical/biological modeling effort to evaluate the drivers of biogeochemical cycles in the fjords and to explore their potential sensitivity to enhanced meltwater and sediment inputs. Fieldwork over two oceanographic cruises will utilize moorings, weather stations, and glacial, sea-ice and seafloor time-lapse cameras to obtain an integrated view of fjord ecosystem processes. The field team will also make multiple shipboard measurements and will use towed and autonomous underwater vehicles to intensively evaluate fjord ecosystem structure and function during spring/summer and autumn seasons. These integrated field and modeling studies are expected to elucidate fundamental properties of water column and sea bottom ecosystem structure and function in the fjords, and to identify key physical-chemical-glaciological forcing in these rapidly warming ecosystems. | POLYGON((-66 -64,-65.6 -64,-65.2 -64,-64.8 -64,-64.4 -64,-64 -64,-63.6 -64,-63.2 -64,-62.8 -64,-62.4 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.4 -65,-62.8 -65,-63.2 -65,-63.6 -65,-64 -65,-64.4 -65,-64.8 -65,-65.2 -65,-65.6 -65,-66 -65,-66 -64.9,-66 -64.8,-66 -64.7,-66 -64.6,-66 -64.5,-66 -64.4,-66 -64.3,-66 -64.2,-66 -64.1,-66 -64)) | POINT(-64 -64.5) | false | false | ||||||||||||||
Collaborative Research: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core
|
1443464 1443710 1443472 |
2019-02-02 | Severinghaus, Jeffrey P.; Sowers, Todd A.; Brook, Edward J. | Gases trapped in ice cores have revealed astonishing things about the greenhouse gas composition of the past atmosphere, including the fact that carbon dioxide concentrations never rose above 300 parts per million during the last 800,000 years. This places today's concentration of 400 parts per million in stark contrast. Furthermore, these gas records show that natural sources of greenhouse gas such as oceans and ecosystems act as amplifiers of climate change by increasing emissions of gases during warmer periods. Such amplification is expected to occur in the future, adding to the human-produced gas burden. The South Pole ice core will build upon these prior findings by expanding the suite of gases to include, for the first time, those potent trace gases that both trapped heat and depleted ozone during the past 40,000 years. The present project on inert gases and methane in the South Pole ice core will improve the dating of this crucial record, to unprecedented precision, so that the relative timing of events can be used to learn about the mechanism of trace gas production and destruction, and consequent climate change amplification. Ultimately, this information will inform predictions of future atmospheric chemical cleansing mechanisms and climate in the context of our rapidly changing atmosphere. This award also engages young people in the excitement of discovery and polar research, helping to entrain the next generations of scientists and educators. Education of graduate students, a young researcher (Buizert), and training of technicians, will add to the nation?s human resource base. <br/> <br/>This award funds the construction of the gas chronology for the South Pole 1500m ice core, using measured inert gases (d15N and d40Ar--Nitrogen and Argon isotope ratios, respectively) and methane in combination with a next-generation firn densification model that treats the stochastic nature of air trapping and the role of impurities on densification. The project addresses fundamental gaps in scientific understanding that limit the accuracy of gas chronologies, specifically a poor knowledge of the controls on ice-core d15N and the possible role of layering and impurities in firn densification. These gaps will be addressed by studying the gas enclosure process in modern firn at the deep core site. The work will comprise the first-ever firn air pumping experiment that has tightly co-located measurements of firn structural properties on the core taken from the same borehole.<br/><br/>The project will test the hypothesis that the lock-in horizon as defined by firn air d15N, CO2, and methane is structurally controlled by impermeable layers, which are in turn created by high-impurity content horizons in which densification is enhanced. Thermal signals will be sought using the inert gas measurements, which improve the temperature record with benefits to the firn densification modeling. Neon, argon, and oxygen will be measured in firn air and a limited number of deep core samples to test whether glacial period layering was enhanced, which could explain low observed d15N in the last glacial period. Drawing on separate volcanic and methane synchronization to well-dated ice cores to create independent ice and gas tie points, independent empirical estimates of the gas age-ice age difference will be made to check the validity of the firn densification model-inert gas approach to calculating the gas age-ice age difference. These points will also be used to test whether the anomalously low d15N seen during the last glacial period in east Antarctic ice cores is due to deep air convection in the firn, or a missing impurity dependence in the firn densification models. <br/><br/>The increased physical understanding gained from these studies, combined with new high-precision measurements, will lead to improved accuracy of the gas chronology of the South Pole ice core, which will enhance the overall science return from this gas-oriented core. This will lead to clarification of timing of atmospheric gas variations and temperature, and aid in efforts to understand the biogeochemical feedbacks among trace gases. These feedbacks bear on the future response of the Earth System to anthropogenic forcing. Ozone-depleting substances will be measured in the South Pole ice core record, and a precise gas chronology will add value. Lastly, by seeking a better understanding of the physics of gas entrapment, the project aims to have an impact on ice-core science in general. | POINT(0 -90) | POINT(0 -90) | false | false | ||||||||||||||
Collaborative Research: Integrative Study of Marine Ice Sheet Stability & Subglacial Life Habitats in W Antarctica - Lake & Ice Stream Subglacial Access Research Drilling (LISSARD)
|
0838855 0838947 0839142 0838763 0838764 0839059 0839107 |
2018-09-10 | Tulaczyk, Slawek; Fisher, Andrew; Powell, Ross; Anandakrishnan, Sridhar; Jacobel, Robert; Scherer, Reed Paul | 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. | None | None | false | false | ||||||||||||||
LTER Palmer, Antarctica (PAL): Land-Shelf-Ocean Connectivity, Ecosystem Resilience and Transformation in a Sea-Ice Influenced Pelagic Ecosystem
|
2023425 1440435 |
2018-05-11 | Ducklow, Hugh; Martinson, Doug; Schofield, Oscar | 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).<br/><br/>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. | 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)) | POINT(-71.5 -67) | false | false | ||||||||||||||
CAREER:Protist Nutritional Strategies in Permanently Stratified Antarctic Lakes
|
1056396 |
2018-02-26 | Morgan-Kiss, Rachael |
|
This CAREER proposal will support an early career female PI to establish an integrated research and education program in the fields of polar biology and environmental microbiology, focusing on single-celled eukaryotes (protists) in high latitude ice-covered Antarctic lakes systems. Protists play important roles in energy flow and material cycling, and act as both primary producers (fixing inorganic carbon by photosynthesis) and consumers (preying on bacteria by phagotrophic digestion). The McMurdo Dry Valleys (MDV) located in Victoria Land, Antarctica, harbor microbial communities which are isolated in the unique aquatic ecosystem of perennially ice-capped lakes. The lakes support exclusively microbial consortia in chemically stratified water columns that are not influenced by seasonal mixing, allochthonous inputs, or direct human impact. This project will exploit permanently stratified biogeochemistry that is unique across the water columns of several MDV lakes to address gaps in our understanding of protist trophic function in aquatic food webs. The proposed research will examine (1) the impact of permanent biogeochemical gradients on protist trophic strategy, (2) the effect of major abiotic drivers (light and nutrients) on the distribution of two key mixotrophic and photoautotrophic protist species, and (3) the effect of episodic nutrient pulses on mixotroph communities in high latitude (ultraoligotrophic) MDV lakes versus low latitude (eutrophic) watersheds. The project will impact the fields of microbial ecology and environmental microbiology by combining results from field, laboratory and in situ incubation studies to synthesize new models for the protist trophic roles in the aquatic food web. The research component of this proposed project will be tightly integrated with the development of two new education activities designed to exploit the inherent excitement associated with polar biological research. The educational objectives are: 1) to establish a teaching module in polar biology in a core undergraduate course for microbiology majors; 2) to develop an instructional module to engage middle school girls in STEM disciplines. Undergraduates and middle school girls will also work with a doctoral student on his experiments in local Ohio watersheds. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM)
|
1425989 |
2017-12-29 | Sarmiento, Jorge; Rynearson, Tatiana | Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) project seeks to drive a transformative shift in our understanding of the crucial role of the Southern Ocean in taking up anthropogenic carbon and heat, and resupplying nutrients from the abyss to the surface. An observational program will generate vast amounts of new biogeochemical data that will provide a greatly improved view of the dynamics and ecosystem responses of the Southern Ocean. A modeling component will apply these observations to enhancing understanding of the current ocean, reducing uncertainty in projections of future carbon and nutrient cycles and climate.<br/><br/>Because it serves as the primary gateway through which the intermediate, deep, and bottom waters of the ocean interact with the surface layers and thus the atmosphere, the Southern Ocean has a profound influence on the oceanic uptake of anthropogenic carbon and heat as well as nutrient resupply from the abyss to the surface. Yet it is the least observed and understood region of the world ocean. The oceanographic community is on the cusp of two major advances that have the potential to transform understanding of the Southern Ocean. The first is the development of new biogeochemical sensors mounted on autonomous profiling floats that allow sampling of ocean biogeochemistry and acidification in 3-dimensional space with a temporal resolution of five to ten days. The SOCCOM float program proposed will increase the average number of biogeochemical profiles measured per month in the Southern Ocean by ~10-30x. The second is that the climate modeling community now has the computational resources and physical understanding to develop fully coupled climate models that can represent crucial mesoscale processes in the Southern Ocean, as well as corresponding models that assimilate observations to produce a state estimate. Together with the observations, this new generation of models provides the tools to vastly improve understanding of Southern Ocean processes and the ability to quantitatively assess uptake of anthropogenic carbon and heat, as well as nutrient resupply, both today and into the future.<br/><br/>In order to take advantage of the above technological and modeling breakthroughs, SOCCOM will implement the following research programs:<br/>* Theme 1: Observations. Scripps Institution of Oceanography will lead a field program to expand the number of Southern Ocean autonomous profiling floats and equip them with sensors to measure pH, nitrate, and oxygen. The University of Washington and Monterey Bay Aquarium Research Institute will design, build, and oversee deployment of the floats. Scripps will also develop a mesoscale eddying Southern Ocean state estimate that assimilates physical and biogeochemical data into the MIT ocean general circulation model.<br/>* Theme 2: Modeling. University of Arizona and Princeton University, together with NOAA's Geophysical Fluid Dynamics Laboratory (GFDL), will use SOCCOM observations to develop data/model assessment metrics and next-generation model analysis and evaluation, with the goal of improving process level understanding and reducing the uncertainty in projections of our future climate.<br/><br/>Led by Climate Central, an independent, non-profit journalism and research organization that promotes understanding of climate science, SOCCOM will collaborate with educators and media professionals to inform policymakers and the public about the challenges of climate change and its impacts on marine life in the context of the Southern Ocean. In addition, the integrated team of SOCCOM scientists and educators will:<br/>* communicate data and results of the SOCCOM efforts quickly to the public through established data networks, publications, broadcast media, and a public portal;<br/>* train a new generation of diverse ocean scientists, including undergraduate students, graduate students, and postdoctoral fellows versed in field techniques, data calibration, modeling, and communication of research to non-scientists;<br/>* transfer new sensor technology and related software to autonomous instrument providers and manufacturers to ensure that they become widely useable. | POLYGON((-180 -52.6153,-168.67689 -52.6153,-157.35378 -52.6153,-146.03067 -52.6153,-134.70756 -52.6153,-123.38445 -52.6153,-112.06134 -52.6153,-100.73823 -52.6153,-89.41512 -52.6153,-78.09201 -52.6153,-66.7689 -52.6153,-66.7689 -55.18958,-66.7689 -57.76386,-66.7689 -60.33814,-66.7689 -62.91242,-66.7689 -65.4867,-66.7689 -68.06098,-66.7689 -70.63526,-66.7689 -73.20954,-66.7689 -75.78382,-66.7689 -78.3581,-78.09201 -78.3581,-89.41512 -78.3581,-100.73823 -78.3581,-112.06134 -78.3581,-123.38445 -78.3581,-134.70756 -78.3581,-146.03067 -78.3581,-157.35378 -78.3581,-168.67689 -78.3581,180 -78.3581,178.62318 -78.3581,177.24636 -78.3581,175.86954 -78.3581,174.49272 -78.3581,173.1159 -78.3581,171.73908 -78.3581,170.36226 -78.3581,168.98544 -78.3581,167.60862 -78.3581,166.2318 -78.3581,166.2318 -75.78382,166.2318 -73.20954,166.2318 -70.63526,166.2318 -68.06098,166.2318 -65.4867,166.2318 -62.91242,166.2318 -60.33814,166.2318 -57.76386,166.2318 -55.18958,166.2318 -52.6153,167.60862 -52.6153,168.98544 -52.6153,170.36226 -52.6153,171.73908 -52.6153,173.1159 -52.6153,174.49272 -52.6153,175.86954 -52.6153,177.24636 -52.6153,178.62318 -52.6153,-180 -52.6153)) | POINT(-130.26855 -65.4867) | false | false | ||||||||||||||
Collaborative Research: Investigating Iron-inding Ligands in Southern Ocean Diatom Communities: The Role of Diatom-Bacteria Associations
|
1443474 |
2017-12-29 | Jenkins, Bethany |
|
This project focuses on an important group of photosynthetic algae in the Southern Ocean (SO), diatoms, and the roles associated bacterial communities play in modulating their growth. Diatom growth fuels the SO food web and balances atmospheric carbon dioxide by sequestering the carbon used for growth to the deep ocean on long time scales as cells sink below the surface. The diatom growth is limited by the available iron in the seawater, most of which is not freely available to the diatoms but instead is tightly bound to other compounds. The nature of these compounds and how phytoplankton acquire iron from them is critical to understanding productivity in this region and globally. The investigators will conduct experiments to characterize the relationship between diatoms, their associated bacteria, and iron in open ocean and inshore waters. Experiments will involve supplying nutrients at varying nutrient ratios to natural phytoplankton assemblages to determine how diatoms and their associated bacteria respond to different conditions. This will provide valuable data that can be used by climate and food web modelers and it will help us better understand the relationship between iron, a key nutrient in the ocean, and the organisms at the base of the food web that use iron for photosynthetic growth and carbon uptake. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project supports early career senior investigators and the training of graduate and undergraduate students as well as outreach activities with middle school Girl Scouts in Rhode Island, inner city middle and high school age girls in Virginia, and middle school girls in Florida.<br/><br/>The project combines trace metal biogeochemistry, phytoplankton cultivation, and molecular biology to address questions regarding the production of iron-binding compounds and the role of diatom-bacterial interactions in this iron-limited region. Iron is an essential micronutrient for marine phytoplankton. Phytoplankton growth in the SO is limited by a lack of sufficient iron, with important consequences for carbon cycling and climate in this high latitude regime. Some of the major outstanding questions in iron biogeochemistry relate to the organic compounds that bind >99.9% of dissolved iron in surface oceans. The investigators' prior research in this region suggests that production of strong iron-binding compounds in the SO is linked to diatom blooms in waters with high nitrate to iron ratios. The sources of these compounds are unknown but the investigators hypothesize that they may be from bacteria, which are known to produce such compounds for their own use. The project will test three hypotheses concerning the production of these iron-binding compounds, limitations on the biological availability of iron even if present in high concentrations, and the roles of diatom-associated bacteria in these processes. Results from this project will provide fundamental information about the biogeochemical trigger, and biological sources and function, of natural strong iron-binding compound production in the SO, where iron plays a critical role in phytoplankton productivity, carbon cycling, and climate regulation. | None | None | false | false | |||||||||||||
NSFGEO-NERC: Evolutionary Response of Southern Ocean Diatoms to Environmental Change
|
1543245 |
2017-12-29 | Rynearson, Tatiana; Bishop, Ian | The research will examine how diatoms (an important group of plankton in the Southern Ocean) adapt to environmental change. Diatoms will be sampled from different regions of the Southern Ocean, including the Drake Passage, the Pacific Sector of the Southern Ocean and the Ross Sea and examined to determine the range of genetic variation among diatoms in these regions. Experiments on a range of diatoms will be conducted in home laboratories and will be aimed at measuring shifts in physiological capacities over many generations in response to directional changes in the environment (temperature and pH). The information on the genetic diversity of field populations combined with information on potential rates of adaptability and genome changes will provide insight into ways in which polar marine diatoms populations may respond to environmental changes that may occur in surface oceans in the future or may have occurred during past climate conditions. Such information allows better modeling of biogeochemical cycles in the ocean as well as improves our abilities to interpret records of past ocean conditions. The project will support a doctoral student and a postdoctoral researcher as well as several undergraduate students. These scientists will learn the fundamentals of experimental evolution, a skill set that is being sought in the fields of biology and oceanography. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting that will design and facilitate a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW). <br/><br/>Both physiological and genetic variation are key parameters for understanding evolutionary processes in phytoplankton but they are essentially unknown for Southern Ocean diatoms. The extent to which these two factors determine plasticity and adaptability in field populations and the interaction between them will influence how and whether cold-adapted diatoms can respond to changing environments. This project includes a combination of field work to identify genetic diversity within diatoms using molecular approaches and experiments in the lab to assess the range of physiological variation in contemporary populations of diatoms and evolution experiments in the lab to assess how the combination of genetic diversity and physiological variation influence the evolutionary potential of diatoms under a changing environment. This research will uncover general relationships between physiological variation, genetic diversity, and evolutionary potential that may apply across microbial taxa and geographical regions, substantially improving efforts to predict shifts in marine ecosystems. Results from this study can be integrated into developing models that incorporate evolution to predict ecosystem changes under future climate change scenarios. | None | None | false | false | ||||||||||||||
Collaborative Research: Investigating Upper Pleistocene Rapid Climate Change using Continuous, Ultra-High-Resolution Aerosol and Gas Measurements in the WAIS Divide Ice Core
|
1142166 |
2017-04-25 | McConnell, Joseph |
|
McConnell/1142166<br/><br/>This award supports a project to use unprecedented aerosol and continuous gas (methane, carbon monoxide) measurements of the deepest section of the West Antarctic Ice Sheet (WAIS) Divide ice core to investigate rapid climate changes in Antarctica during the ~60,000 year long Marine Isotope Stage 3 period of the late Pleistocene. These analyses, combined with others, will take advantage of the high snow accumulation of the WAIS Divide ice core to yield the highest time resolution glaciochemical and gas record of any deep Antarctic ice core for this time period. The research will expand already funded discrete gas measurements and extend currently funded continuous aerosol measurements on the WAIS Divide ice core from ~25,000 to ~60,000 years before present, spanning Heinrich events 3 to 6 and Antarctic Isotope Maximum (AIM, corresponding to the Northern Hemisphere Dansgaard-Oeschger) events 3 to 14. With other high resolution Greenland cores and lower resolution Antarctic cores, the combined record will yield new insights into worldwide climate dynamics and abrupt change. The intellectual merit of the work is that it will be used to address the science goals of the WAIS Divide project including the identification of dust and biomass burning tracers such as black carbon and carbon monoxide which reflect mid- and low-latitude climate and atmospheric circulation patterns, and fallout from these sources affects marine and terrestrial biogeochemical cycles. Similarly, sea salt and ocean productivity tracers reflect changes in sea ice extent, marine primary productivity, wind speeds above the ocean, and atmospheric circulation. Volcanic tracers address the relationship between northern, tropical, and southern climates as well as stability of the West Antarctic ice sheet and sea level change. When combined with other gas records from WAIS Divide, the records developed here will transform understanding of mid- and low-latitude drivers of Antarctic, Southern Hemisphere, and global climate rapid changes and the timing of such changes. The broader impacts of the work are that it will enhance infrastructure through expansion of continuous ice core analytical techniques, train students and support collaboration between two U.S. institutions (DRI and OSU). All data will be made available to the scientific community and the public and will include participation the WAIS Divide Outreach Program. Extensive graduate and undergraduate student involvement is planned. Student recruitment will be made from under-represented groups building on a long track record. Broad outreach will be achieved through collaborations with the global and radiative modeling communities, NESTA-related and other educational outreach efforts, and public lectures. This proposed project does not require field work in the Antarctic. | POINT(-112.1115 -79.481) | POINT(-112.1115 -79.481) | false | false | |||||||||||||
Fugitive Gases (Helium, Neon, and Oxygen) in the WAIS Divide Ice Core as Tracers of Basal Processes and Past Biospheric Carbon Storage
|
1143619 |
2015-07-13 | Severinghaus, Jeffrey P. | No dataset link provided | This award supports a project to extend the study of gases in ice cores to those gases whose small molecular diameters cause them to escape rapidly from ice samples (the so-called "fugitive gases"). The work will employ helium, neon, argon, and oxygen measurements in the WAIS Divide ice core to better understand the mechanism of the gas close-off fractionation that occurs while air bubbles are incorporated into ice. The intellectual merit of the proposed work is that corrections for this fractionation using neon (which is constant in the atmosphere) may ultimately enable the first ice core-based atmospheric oxygen and helium records. Neon may also illuminate the mechanistic link between local insolation and oxygen used for astronomical dating of ice cores. Helium measure-ments in the deepest ~100 m of the core will also shed light on the stratigraphic integrity of the basal ice, and serve as a probe of solid earth-ice interaction at the base of the West Antarctic ice sheet. Past atmospheric oxygen records, currently unavailable prior to 1989 CE, would reveal changes in the size of the terrestrial biosphere carbon pool that accompany climate variations and place constraints on the biogeochemical feedback response to future warming. An atmospheric helium-3/helium-4 record would test the hypothesis that the solar wind (which is highly enriched in helium-3) condensed directly into Earth?s atmosphere during the collapse of the geomagnetic field that occurred 41,000 years ago, known as the Laschamp Event. Fugitive-gas samples will be taken on-site immediately after recovery of the ice core by the PI and one postdoctoral scholar, under the umbrella of an existing project to support replicate coring and borehole deepening. This work will add value to the scientific return from field work activity with little additional cost to logistical resources. The broader impacts of the work on atmospheric oxygen are that it may increase understanding of how terrestrial carbon pools and atmospheric greenhouse gas sources will respond in a feedback sense to the coming warming. Long-term atmospheric oxygen trends are also of interest for understanding biogeochemical regulatory mechanisms and the impact of atmospheric evolution on life. Helium records have value in understanding the budget of this non-renewable gas and its implications for space weather and solar activity. The project will train one graduate student and one postdoctoral scholar. The fascination of linking solid earth, cryosphere, atmosphere, and space weather will help to entrain and excite young scientists and efforts to understand the Earth as a whole interlinked system will provide fuel to outreach efforts at all ages. | POINT(-112.09 -79.47) | POINT(-112.09 -79.47) | false | false | |||||||||||||
Collaborative Research: Impact of Mesoscale Processes on Iron Supply and Phytoplankton Dynamics in the Ross Sea
|
0944254 0944165 |
2015-07-08 | Smith, Walker; McGillicuddy, Dennis |
|
The Ross Sea continental shelf is one of the most productive areas in the Southern Ocean, and may comprise a significant, but unaccounted for, oceanic CO2 sink, largely driven by phytoplankton production. The processes that control the magnitude of primary production in this region are not well understood, but data suggest that iron limitation is a factor. Field observations and model simulations indicate four potential sources of dissolved iron to surface waters of the Ross Sea: (1) circumpolar deep water intruding from the shelf edge; (2) sediments on shallow banks and nearshore areas; (3) melting sea ice around the perimeter of the polynya; and (4) glacial meltwater from the Ross Ice Shelf. The principal investigators hypothesize that hydrodynamic transport via mesoscale currents, fronts, and eddies facilitate the supply of dissolved iron from these four sources to the surface waters of the Ross Sea polynya. These hypotheses will be tested through a combination of in situ observations and numerical modeling, complemented by satellite remote sensing. In situ observations will be obtained during a month-long cruise in the austral summer. The field data will be incorporated into model simulations, which allow quantification of the relative contributions of the various hypothesized iron supply mechanisms, and assessment of their impact on primary production. The research will provide new insights and a mechanistic understanding of the complex oceanographic phenomena that regulate iron supply, primary production, and biogeochemical cycling. The research will thus form the basis for predictions about how this system may change in a warming climate. The broader impacts include training of graduate and undergraduate students, international collaboration, and partnership with several ongoing outreach programs that address scientific research in the Southern Ocean. The research also will contribute to the goals of the international research programs ICED (Integrated Climate and Ecosystem Dynamics) and GEOTRACES (Biogeochemical cycling and trace elements in the marine environment). | POLYGON((168 -65,168.2 -65,168.4 -65,168.6 -65,168.8 -65,169 -65,169.2 -65,169.4 -65,169.6 -65,169.8 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,170 -65,169.8 -65,169.6 -65,169.4 -65,169.2 -65,169 -65,168.8 -65,168.6 -65,168.4 -65,168.2 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65,168 -65)) | POINT(169 -65) | false | false | |||||||||||||
Collaborative Research: The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica
|
0838970 |
2014-10-10 | Foreman, Christine |
|
Dissolved organic matter (DOM) comprises a significant pool of Earth's organic carbon that dwarfs the amount present in living aquatic organisms. The properties and reactivity of DOM are not well defined, and the evolution of autochthonous DOM from its precursor materials in freshwater has not been observed. Recent sampling of a supraglacial stream formed on the Cotton Glacier in the Transantarctic Mountains revealed DOM that more closely resembles an assemblage of recognizable precursor organic compounds, based upon its UV-VIS and fluorescence spectra. It is suggested that the DOM from this water evolved over time to resemble materials present in marine and many inland surface waters. The transient nature of the system i.e., it reforms seasonally, also prevents any accumulation of the refractory DOM present in most surface waters. Thus, the Cotton Glacier provides us with a unique environment to study the formation of DOM from precursor materials. An interdisciplinary team will study the biogeochemistry of this progenitor DOM and how microbes modify it. By focusing on the chemical composition of the DOM as it shifts from precursor material to the more humified fractions, the investigators will relate this transition to bioavailability, enzymatic activity, community composition and microbial growth efficiency. This project will support education at all levels, K-12, high school, undergraduate, graduate and post-doc and will increase participation by under-represented groups in science. Towards these goals, the investigators have established relationships with girls' schools and Native American programs. Additional outreach will be carried out in coordination with PolarTREC, PolarPalooza, and if possible, an Antarctic Artist and Writer. | POINT(161.667 -77.117) | POINT(161.667 -77.117) | false | false | |||||||||||||
Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core
|
0839075 0839093 0839122 |
2014-05-30 | Foreman, Christine; Skidmore, Mark; Saltzman, Eric; McConnell, Joseph; Priscu, John | 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 use the WAIS Divide deep core to investigate the Last Deglaciation at sub-annual resolution through an integrated set of chemical and biological analyses. The intellectual merit of the project is that these analyses, combined with others, will take advantage of the high snow accumulation WAIS Divide site yielding the highest time resolution glacio-biogeochemical and gas record of any deep Antarctic ice core. With other high resolution Greenland cores (GISP2 and GRIP) and lower resolution Antarctic cores, the combined record will yield new insights into worldwide climate dynamics and abrupt change. The proposed chemical, biological, and elemental tracer measurements will also be used to address all of the WAIS Divide science themes. The broader impacts of the project include education and outreach activities such as numerous presentations to local K-12 students; opportunities for student and teacher involvement in the laboratory work; a teacher training program in Earth sciences in the heavily minority Santa Ana, Compton, and Costa Mesa, California school districts; and development of high school curricula. Extensive graduate and undergraduate student involvement also is planned and will include one post doctoral associate, one graduate student, and undergraduate hourly involvement at DRI; a graduate student and undergraduates at University of California, Irvine (UCI); and a post doctoral fellow at MSU. Student recruitment will be made from underrepresented groups building on a long track record of involvement and will include the NSF funded California Alliance for Minority Participation (CAMP) and the Montana American Indian Research Opportunities (AIRO).<br/><br/>This award does not involve field work in Antarctica. | POINT(112.05 -79.28) | POINT(112.05 -79.28) | false | false | ||||||||||||||
Ammonia Oxidation Versus Heterotrophy in Crenarchaeota Populations from Marine Environments West of the Antarctic Peninsula
|
0838996 |
2014-03-13 | Hollibaugh, James T. |
|
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. | 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)) | POINT(-71.5 -67) | false | false | |||||||||||||
Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem
|
0838830 |
2013-12-16 | Cottrell, Matthew; David, Kirchman |
|
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>Light quality and availability are likely to change in polar ecosystems as ice coverage and thickness decrease. How microbes adjust to these and other changes will have huge impacts on the polar marine ecosystems. Little is known about photoheterotrophic prokaryotes, which are hypothesized to gain a metabolic advantage by harvesting light energy in addition to utilizing dissolved organic matter (DOM). Photoheterotrophy is not included in current models of carbon cycling and energy flow. This research will examine three questions: 1. Are photoheterotrophic microbes present and active in Antarctic waters in winter and summer? 2. Does community structure of photoheterotrophs shift between summer and winter? 3. Which microbial groups assimilate more DOM in light than in the dark? The research will test hypotheses about activity of photoheterotrophs in winter and in summer, shifts in community structure between light and dark seasons and the potentially unique impacts of photoheterotrophs on biogeochemical processes in the Antarctic. The project will directly support a graduate student, will positively impact the NSF REU program at the College of Marine and Earth Studies, and will include students from the nation?s oldest historical minority college. The results will be featured during weekly tours of Lewes facilities (about 1000 visitors per year) and during Coast Day, an annual open-house that attracts about 10,000 visitors. | POLYGON((-64.079666 -64.77966,-64.07576590000001 -64.77966,-64.0718658 -64.77966,-64.0679657 -64.77966,-64.0640656 -64.77966,-64.06016550000001 -64.77966,-64.0562654 -64.77966,-64.0523653 -64.77966,-64.04846520000001 -64.77966,-64.0445651 -64.77966,-64.040665 -64.77966,-64.040665 -64.78326100000001,-64.040665 -64.786862,-64.040665 -64.790463,-64.040665 -64.794064,-64.040665 -64.797665,-64.040665 -64.801266,-64.040665 -64.804867,-64.040665 -64.808468,-64.040665 -64.812069,-64.040665 -64.81567,-64.0445651 -64.81567,-64.04846520000001 -64.81567,-64.0523653 -64.81567,-64.0562654 -64.81567,-64.06016550000001 -64.81567,-64.0640656 -64.81567,-64.0679657 -64.81567,-64.0718658 -64.81567,-64.07576590000001 -64.81567,-64.079666 -64.81567,-64.079666 -64.812069,-64.079666 -64.808468,-64.079666 -64.804867,-64.079666 -64.801266,-64.079666 -64.797665,-64.079666 -64.794064,-64.079666 -64.790463,-64.079666 -64.786862,-64.079666 -64.78326100000001,-64.079666 -64.77966)) | POINT(-64.0601655 -64.797665) | false | false | |||||||||||||
Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica
|
0739681 0739698 |
2013-12-12 | Murray, Alison; Doran, Peter |
|
Lake Vida is the largest lake of the McMurdo Dry Valleys, with an approximately 20 m ice cover overlaying a brine of unknown depth with at least 7 times seawater salinity and temperatures below -10 degrees C year-round. Samples of brine collected from ice above the main water body contain 1) the highest nitrous oxide levels of any natural water body on Earth, 2) unusual geochemistry including anomalously high ammonia and iron concentrations, 3) high microbial counts with an unusual proportion (99%) of ultramicrobacteria. The microbial community is unique even compared to other Dry Valley Lakes. The research proposes to enter, for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical and microbiological analyses. The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake's history. The research will be conducted by a multidisciplinary team that will uncover the biogeochemical processes associated with a non-photosynthetic microbial community isolated for a significant period of time. This research will address diversity, adaptive mechanisms and evolutionary processes in the context of the physical evolution of the environment of Lake Vida. Results will be widely disseminated through publications, presentations at national and international meetings, through the Subglacial Antarctic Lake Exploration (SALE) web site and the McMurdo LTER web site. The research will support three graduate students and three undergraduate research assistants. The results will be incorporated into a new undergraduate biogeosciences course at the University of Illinois at Chicago which has an extremely diverse student body, dominated by minorities. | POINT(161.931 -77.3885) | POINT(161.931 -77.3885) | false | false | |||||||||||||
Collaborative Research: The Role of Snow Patches on the Spatial Distribution of Soil Microbial Communities and Biogeochemical Cycling in the Antarctic Dry Valleys
|
0838850 |
2013-11-26 | Gooseff, Michael N. |
|
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>Two models have been proposed to describe controls over microbial biogeography. One model proposes that microbes are ubiquitously distributed across the global environment, and that environmental conditions select for taxa physiologically adapted to local physical conditions. An alternative model predicts that dispersal is the important limitation to the distribution of microorganisms and that spatial heterogeneity of microbial communities is a result of both dispersal and local environmental limitations. According to both models, spatial heterogeneity of microbial communities may be especially pronounced in extreme ecosystems where the environmental selection for organisms with suitable physiology is most strongly manifest. We propose that Antarctic terrestrial environments are ideal places to examine microbial biogeography for 3 reasons: 1) the pristine nature and remoteness of Antarctica minimizes the prevalence of exotic species dispersed through human vectors; 2) the extreme conditions of Antarctic environments provide a strong environmental filter which limits the establishment of non-indigenous taxa; and 3) extreme heterogeneity in the terrestrial environment provides natural gradients of soil conditions (temperature, water and nutrient availability). In the proposed research we will investigate the influence of snow on the composition and spatial distribution of soil microbial communities and linked biogeochemical cycling in the McMurdo Dry Valleys. We will conduct fieldwork at the landscape scale (repeated remote sensing to characterize snow distribution), at the valley and patch scales (quantify snow patch ablation, microbial communities and biogeochemical cycling in subnivian soils). We hypothesize that snow patches play an important role in structuring the spatial distribution of soil microbial communities and their associated ecosystem functioning because of the physical and hydrological influences that snow patches have on the soil environment. The research will contribute to greater public awareness of the importance of polar research to fundamental questions of biology, ecology and hydrology through direct linkages with International Antarctic Institute public outreach activities, including dissemination of web-based learning units on environmental science and microbiology, targeted as resources for secondary and post-secondary educators. Three graduate students, one postdoctoral scholar and multiple undergraduates will participate in the research activities. | POLYGON((162.32 -77.62,162.418 -77.62,162.516 -77.62,162.614 -77.62,162.712 -77.62,162.81 -77.62,162.90800000000002 -77.62,163.006 -77.62,163.104 -77.62,163.202 -77.62,163.3 -77.62,163.3 -77.631,163.3 -77.64200000000001,163.3 -77.653,163.3 -77.664,163.3 -77.67500000000001,163.3 -77.686,163.3 -77.697,163.3 -77.708,163.3 -77.71900000000001,163.3 -77.73,163.202 -77.73,163.104 -77.73,163.006 -77.73,162.90800000000002 -77.73,162.81 -77.73,162.712 -77.73,162.614 -77.73,162.516 -77.73,162.418 -77.73,162.32 -77.73,162.32 -77.71900000000001,162.32 -77.708,162.32 -77.697,162.32 -77.686,162.32 -77.67500000000001,162.32 -77.664,162.32 -77.653,162.32 -77.64200000000001,162.32 -77.631,162.32 -77.62)) | POINT(162.81 -77.675) | false | false | |||||||||||||
Collaborative Research: Modeling and synthesis study of a natural iron fertilization site in the Southern Drake Passage
|
0948357 0948338 |
2013-11-22 | Mitchell, B.; Azam, Farooq; Barbeau, Katherine; Gille, Sarah; Holm-Hansen, Osmund; Measures, Christopher; Selph, Karen |
|
The ocean plays a critical role in sequestering CO2 by exporting fixed carbon to the deep ocean through the biological pump. There is a pressing need to understand the systematics of carbon export in the Southern Ocean in the context of global warming because of the sensitivity of this region to climate change, already manifested as significant temperature increases. Numerous studies have indicated that Fe supply is a primary control on phytoplankton biomass and productivity in the Southern Ocean. The results from previous cruises in Feb-Mar 2004 and Jul-Aug 2006 have revealed the major natural Fe fertilization from Fe-rich shelf waters to the Fe-limited high nutrient low chlorophyll (HNLC) Antarctic Circumpolar Current Surface Water (ASW) in the southern Drake Passage, producing a series of phytoplankton blooms. Remaining questions include: How is natural Fe transported to the euphotic zone through small-meso-large scale horizontal-vertical transport and mixing in different HNLC ACC areas? How does plankton community structure evolve in response to a natural Fe addition, how does Fe speciation respond to biogeochemical processes, and how is Fe recycled to determine the longevity of phytoplankton blooms? How does the export of POC evolve as a function of upwelling-mixing, Fe addition-recycling and bacteria-plankton structure? This synthesis proposal will address these fundamental questions using a unique dataset combining multiyear physical, Fe and biogeochemical data collected between 2004 and 2006 from 2 NSF-funded Fe fertilization experiment cruises and 3 Antarctic Marine Living Resource (AMLR) cruises in the southern Drake Passage and southwestern Scotia Sea through collaboration with scientists in the AMLR program and US Southern Ocean GLOBEC projects. All investigators involved in this study are engaged in graduate and undergraduate instruction, and mentoring of postdoctoral researchers. Each P.I. will incorporate key elements of the proposed syntheses in our lectures, problem sets and group projects. The project includes support to convene a 4-5 day international workshop on natural Fe fertilization at Woods Hole Oceanographic Institution. The workshop will include scientists from United Kingdom, France and Germany who have conducted natural Fe fertilization experiments, and Korea and China who are planning to conduct natural Fe fertilization experiments. The participation of graduate students and postdoctoral scholars will be especially encouraged. The results will be published in a Deep-Sea Research II special issue. | POLYGON((-63 -60,-62 -60,-61 -60,-60 -60,-59 -60,-58 -60,-57 -60,-56 -60,-55 -60,-54 -60,-53 -60,-53 -60.45,-53 -60.9,-53 -61.35,-53 -61.8,-53 -62.25,-53 -62.7,-53 -63.15,-53 -63.6,-53 -64.05,-53 -64.5,-54 -64.5,-55 -64.5,-56 -64.5,-57 -64.5,-58 -64.5,-59 -64.5,-60 -64.5,-61 -64.5,-62 -64.5,-63 -64.5,-63 -64.05,-63 -63.6,-63 -63.15,-63 -62.7,-63 -62.25,-63 -61.8,-63 -61.35,-63 -60.9,-63 -60.45,-63 -60)) | POINT(-58 -62.25) | false | false | |||||||||||||
Collaborative Research: Seasonal Evolution of Chemical and Biological Variability in the Ross Sea
|
0838948 |
2013-11-14 | 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 | None | None | false | false | |||||||||||||
Palmer, Antarctica Long Term Ecological Research Project
|
0823101 |
2013-06-24 | Ducklow, Hugh |
|
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. | None | None | false | false | |||||||||||||
Collaborate Research:Modified Circumpolar Deep Water Intrusions as an Iron Source to the Summer Ross Sea Ecosystem
|
0839039 |
2012-01-17 | Kohut, Josh |
|
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).<br/><br/>An interdisciplinary team of researchers will focus on describing the high productivity patchiness observed in phytoplankton blooms in the mid to late summer in the Ross Sea, Antarctica. Key hypotheses to be tested and extended are that intrusions of nutrient and micro nutrient (e.g. Fe) rich water masses of the Antarctic modified circumpolar deep water (CDW) up onto continental shelves act to control the biogeochemical response of a large area of the productive Ross Sea coastal region. It is believed that this enhanced productivity may be a significant contributing factor to the global carbon cycle. <br/><br/>A novel sampling strategy to be used to test the above hypotheses will employ a remotely controlled deep (1000m) glider (AUV) to locate and map CDW in near real time measuring C (conductivity), T (temperature), D (pressure) and apparent optical properties, and which will serve to direct further ship-based sampling. <br/><br/>The adaptive coordination of a polar research vessel with an AUV additionally provides an opportunity to engage in formal and informal education and public outreach on issues in polar research. | None | None | false | false | |||||||||||||
Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica
|
0230497 |
2012-01-17 | Kiene, Ronald |
|
Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world's highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. <br/><br/>This project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. <br/><br/>Both Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences. | None | None | false | false | |||||||||||||
Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica
|
0230499 |
2012-01-17 | Kiene, Ronald |
|
Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world's highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. <br/><br/>This project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. <br/><br/>Both Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences. | POLYGON((-179.99998 -43.58056,-143.999984 -43.58056,-107.999988 -43.58056,-71.999992 -43.58056,-35.999996 -43.58056,0 -43.58056,35.999996 -43.58056,71.999992 -43.58056,107.999988 -43.58056,143.999984 -43.58056,179.99998 -43.58056,179.99998 -46.971468,179.99998 -50.362376,179.99998 -53.753284,179.99998 -57.144192,179.99998 -60.5351,179.99998 -63.926008,179.99998 -67.316916,179.99998 -70.707824,179.99998 -74.098732,179.99998 -77.48964,143.999984 -77.48964,107.999988 -77.48964,71.999992 -77.48964,35.999996 -77.48964,0 -77.48964,-35.999996 -77.48964,-71.999992 -77.48964,-107.999988 -77.48964,-143.999984 -77.48964,-179.99998 -77.48964,-179.99998 -74.098732,-179.99998 -70.707824,-179.99998 -67.316916,-179.99998 -63.926008,-179.99998 -60.5351,-179.99998 -57.144192,-179.99998 -53.753284,-179.99998 -50.362376,-179.99998 -46.971468,-179.99998 -43.58056)) | POINT(0 -89.999) | false | false | |||||||||||||
Tracing Glacial-interglacial Changes in the Dust Source to Antarctica using Helium Isotopes
|
0636898 |
2011-11-30 | Winckler, Gisela | No dataset link provided | 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. | None | None | false | false | |||||||||||||
WAPflux - New Tools to Study the Fate of Phytoplankton Production in the West Antarctic Peninsula
|
0838866 |
2011-08-31 | Buesseler, Ken; Valdes, James |
|
Abstract<br/><br/><br/>By using a tool-box of particle flux and characterization techniques appropriate to the study of particulate organic carbon fluxes out of the upper sunlit zone, WHOI researchers will attempt to evaluate the so called 'biological pump' term at the Palmer Long Term Ecological Research (PAL) site in the Western Antarctic Peninsula (WAP). The goal of these measurements is to describe the seasonal dynamics of production, export (sinking) and at-depth remineralization rates of organic matter produced in the Antarctic photic zone. This should lead to a better understanding of the biogeochemical controls on the carbon cycle in this difficult to access region. Additionally, how much of the newly fixed organic carbon is exported off the shelf, effectively driving an influx of atmospheric (including anthropogenic) CO2 to be sequestered into the deep ocean is not presently known. Comparison of prior time series sediment traps in the WAP seem to indicate smaller sinking C fluxes than other, as equally as productive Antarctic coastal regions, e.g. the Ross Sea. New observations and modeling activities will attempt to explain this discrepancy, and to account for the apparently inefficient particle export. <br/><br/><br/>"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." | POLYGON((-75 -62,-74 -62,-73 -62,-72 -62,-71 -62,-70 -62,-69 -62,-68 -62,-67 -62,-66 -62,-65 -62,-65 -62.8,-65 -63.6,-65 -64.4,-65 -65.2,-65 -66,-65 -66.8,-65 -67.6,-65 -68.4,-65 -69.2,-65 -70,-66 -70,-67 -70,-68 -70,-69 -70,-70 -70,-71 -70,-72 -70,-73 -70,-74 -70,-75 -70,-75 -69.2,-75 -68.4,-75 -67.6,-75 -66.8,-75 -66,-75 -65.2,-75 -64.4,-75 -63.6,-75 -62.8,-75 -62)) | POINT(-70 -66) | false | false | |||||||||||||
WAIS DIVIDE - High Temporal Resolution Black Carbon Record of Southern Hemisphere Biomass Burning
|
0739780 |
2011-04-28 | Brook, Edward J.; McConnell, Joseph; Mitchell, Logan E; Sowers, Todd A.; Taylor, Kendrick C. |
|
Edwards/0739780<br/><br/>This award supports a project to develop a 2,000-year high-temporal resolution record of biomass burning from the analysis of black carbon in the WAIS Divide bedrock ice core. Pilot data for the WAIS WD05A core demonstrates that we now have the ability to reconstruct this record with minimal impact on the amount of ice available for other projects. The intellectual merit of this project is that black carbon (BC) aerosols result solely from combustion and play a critical but poorly quantified role in global climate forcing and the carbon cycle. When incorporated into snow and ice, BC increases absorption of solar radiation making seasonal snow packs, mountain glaciers, polar ice sheets, and sea ice much more vulnerable to climate warming. BC emissions in the Southern Hemisphere are dominated by biomass burning in the tropical regions of Southern Africa, South America and South Asia. Biomass burning, which results from both climate and human activities, alters the atmospheric composition of greenhouse gases, aerosols and perturbs key biogeochemical cycles. A long-term record of biomass burning is needed to aid in the interpretation of ice core gas composition and will provide important information regarding human impacts on the environment and climate before instrumental records. The broader impacts of the project are that it represents a paradigm shift in our ability to reconstruct the history of fire from ice core records and to understand its impact on atmospheric chemistry and climate over millennial time scales. This type of data is especially needed to drive global circulation model simulations of black carbon aerosols, which have been found to be an important component of global warming and which may be perturbing the hydrologic cycle. The project will also employ undergraduate students and is committed to attracting underrepresented groups to the physical sciences. The project?s outreach component will be conducted as part of the WAIS project outreach program and will reach a wide audience. | POINT(-112.117 -79.666) | POINT(-112.117 -79.666) | false | false | |||||||||||||
Collaborative Reseach: Free-drifting Icebergs as Proliferating Dispersion Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean.
|
0636730 |
2010-11-22 | Vernet, Maria |
|
Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions:1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children's books will participate in cruises to produce an account of the expedition and a daily interactive website. | POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52)) | POINT(-47.5 -58.5) | false | false | |||||||||||||
Collaborative Research: Free Drifting Icebergs as Proliferation Sites of Iron Enrichment, Organic Carbon Production and Export in the Southern Ocean
|
0636543 0636440 0636723 0636319 |
2010-11-22 | Twining, Benjamin; Shaw, Tim; Long, David; Murray, Alison; Helly, John | Atmospheric warming has been associated with retreating glaciers, disintegrating ice shelves, and the increasing prevalence of icebergs in the Southern Ocean over the last decade. Our preliminary study of two icebergs in the NW Weddell Sea, an area of high iceberg concentration, showed significant delivery of terrestrial material accompanied by significant enhancement of phytoplankton and zooplankton/micronekton abundance, and primary production surrounding the icebergs. We hypothesize that nutrient enrichment by free-drifting icebergs will increase primary production and sedimentation of organic carbon, thus increasing the draw-down and sequestration of CO2 in the Southern Ocean and impacting the global carbon cycle. Our research addresses the following questions:1) What is the relationship between the physical dynamics of free-drifting icebergs and the Fe and nutrient distributions of the surrounding water column? 2) What is the relationship between Fe and nutrient distributions associated with free-drifting icebergs and the organic carbon dynamics of the ice-attached and surrounding pelagic communities (microbes, zooplankton, micronekton)? 3) What is impact on the export flux of particulate organic carbon from the mixed layer? An interdisciplinary approach is proposed to examine iceberg structure and dynamics, biogeochemical processes, and carbon cycling that includes measurement of trace element, nutrient and radionuclide distributions; organic carbon dynamics mediated by microbial, ice-attached and zooplankton communities; and particulate organic carbon export fluxes. Results from this project will further our understanding of the relationship between climate change and carbon sequestration in the Southern Ocean. Our findings will be incorporated into the Antarctic Research division of the Ocean Exploration Center (OEC) as part of the SIOExplorer: Digital Library Project. The OEC allows users to access content, which is classified to one of four levels: entry (grade K-6), student (grade 6-12), college, and research. Graduate students, undergraduates, teachers, and volunteers are important participants in the proposed field and laboratory work. For the K-12 level, a professional writer of children's books will participate in cruises to produce an account of the expedition and a daily interactive website. | POLYGON((-55 -52,-53.5 -52,-52 -52,-50.5 -52,-49 -52,-47.5 -52,-46 -52,-44.5 -52,-43 -52,-41.5 -52,-40 -52,-40 -53.3,-40 -54.6,-40 -55.9,-40 -57.2,-40 -58.5,-40 -59.8,-40 -61.1,-40 -62.4,-40 -63.7,-40 -65,-41.5 -65,-43 -65,-44.5 -65,-46 -65,-47.5 -65,-49 -65,-50.5 -65,-52 -65,-53.5 -65,-55 -65,-55 -63.7,-55 -62.4,-55 -61.1,-55 -59.8,-55 -58.5,-55 -57.2,-55 -55.9,-55 -54.6,-55 -53.3,-55 -52)) | POINT(-47.5 -58.5) | false | false | ||||||||||||||
Collaborative Research: Salpa Thompsoni in the Southern Ocean: Bioenergetics, Population Dynamics and Biogeochemical Impact
|
0338090 0338290 |
2010-05-04 | Kremer, Patricia; Madin, Larry; Halanych, Kenneth |
|
Salps are planktonic grazers that have a life history, feeding biology and population dynamic strikingly different from krill, copepods or other crustacean zooplankton. Salps can occur in very dense population blooms that cover large areas and have been shown to have major impacts due to the their grazing and the production of fast-sinking fecal pellets. Although commonly acknowledged as a major component of the Southern Ocean zooplankton community, often comparable in biomass and distribution to krill, salps have received relatively little attention. Although extensive sampling has documented the seasonal abundance of salps in the Southern Ocean, there is a paucity of data on important rates that determine population growth and the role of this species in grazing and vertical flux of particulates. This proposed study will include: measurements of respiration and excretion rates for solitary and aggregate salps of all sizes; measurements of ingestion rates, including experiments to determine the size or concentration of particulates that can reduce ingestion; and determination of growth rates of solitaries and aggregates. In addition to the various rate measurements, this study will include quantitative surveys of salp horizontal and vertical distribution to determine their biomass and spatial distribution, and to allow a regional assessment of their effects. Measurements of the physical characteristics of the water column and the quantity and quality of particulate food available for the salps at each location will also be made. Satellite imagery and information on sea-ice cover will be used to test hypotheses about conditions that result in high densities of salps. Results will be used to construct a model of salp population dynamics, and both experimental and modeling results will be interpreted within the context of the physical and nutritional conditions to which the salps are exposed. This integrated approach will provide a good basis for understanding the growth dynamics of salp blooms in the Southern Ocean. Two graduate students will be trained on this project, and cruise and research experience will be provided for two undergraduate students. A portion of a website allowing students to be a virtual participant in the research will be created to strengthen students' quantitative skills. Both PI's will participate in teacher-researcher workshops, and collaboration with a regional aquarium will be developed in support of public education. | POLYGON((-69.9083 -52.7624,-68.96368 -52.7624,-68.01906 -52.7624,-67.07444 -52.7624,-66.12982 -52.7624,-65.1852 -52.7624,-64.24058 -52.7624,-63.29596 -52.7624,-62.35134 -52.7624,-61.40672 -52.7624,-60.4621 -52.7624,-60.4621 -54.01423,-60.4621 -55.26606,-60.4621 -56.51789,-60.4621 -57.76972,-60.4621 -59.02155,-60.4621 -60.27338,-60.4621 -61.52521,-60.4621 -62.77704,-60.4621 -64.02887,-60.4621 -65.2807,-61.40672 -65.2807,-62.35134 -65.2807,-63.29596 -65.2807,-64.24058 -65.2807,-65.1852 -65.2807,-66.12982 -65.2807,-67.07444 -65.2807,-68.01906 -65.2807,-68.96368 -65.2807,-69.9083 -65.2807,-69.9083 -64.02887,-69.9083 -62.77704,-69.9083 -61.52521,-69.9083 -60.27338,-69.9083 -59.02155,-69.9083 -57.76972,-69.9083 -56.51789,-69.9083 -55.26606,-69.9083 -54.01423,-69.9083 -52.7624)) | POINT(-65.1852 -59.02155) | false | false | |||||||||||||
Collaborative Research: Interactive effects of UV and vertical mixing on phytoplankton and bacterioplankton in the Ross Sea
|
0125818 |
2010-05-04 | Neale, Patrick |
|
Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea. | None | None | false | false | |||||||||||||
Long-term Ecological Research (LTER) on the Antarctic Marine Ecosystem: Microbiology and Carbon Flux
|
9118439 |
2010-05-04 | Karl, David; Ross, Robin Macurda |
|
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. | 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)) | POINT(-67.58825 -60.67125) | false | false | |||||||||||||
Collaborative Research: Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea
|
0338097 0127037 0338350 0741411 0338157 |
2010-05-04 | Ditullio, Giacomo; Smith, Walker; Dryer, Jennifer; Neale, Patrick | The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. <br/>This project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images. | POLYGON((173.31833 -46.5719,173.757539 -46.5719,174.196748 -46.5719,174.635957 -46.5719,175.075166 -46.5719,175.514375 -46.5719,175.953584 -46.5719,176.392793 -46.5719,176.832002 -46.5719,177.271211 -46.5719,177.71042 -46.5719,177.71042 -48.759516,177.71042 -50.947132,177.71042 -53.134748,177.71042 -55.322364,177.71042 -57.50998,177.71042 -59.697596,177.71042 -61.885212,177.71042 -64.072828,177.71042 -66.260444,177.71042 -68.44806,177.271211 -68.44806,176.832002 -68.44806,176.392793 -68.44806,175.953584 -68.44806,175.514375 -68.44806,175.075166 -68.44806,174.635957 -68.44806,174.196748 -68.44806,173.757539 -68.44806,173.31833 -68.44806,173.31833 -66.260444,173.31833 -64.072828,173.31833 -61.885212,173.31833 -59.697596,173.31833 -57.50998,173.31833 -55.322364,173.31833 -53.134748,173.31833 -50.947132,173.31833 -48.759516,173.31833 -46.5719)) | POINT(175.514375 -57.50998) | false | false | ||||||||||||||
Latitudinal Variations of Particle Fluxes in the Southern Ocean: A Bottom Tethered Sediment Trap Array Experiment
|
9614028 |
2010-05-04 | Dymond, Jack |
|
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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Benthic Faunal Feeding Dynamics on the Antarctic Shelf and the Effects of Global Climate Change on Bentho-Pelagic Coupling
|
0636773 0636806 |
2010-05-04 | DeMaster, David; Smith, Craig | The Antarctic Peninsula region exhibits one of the largest warming trends in the world. Climate change in this region will reduce the duration of winter sea-ice cover, altering both the pelagic ecosystem and bentho-pelagic coupling. We postulate that shelf benthic ecosystems are highly suitable for tracking climate change because they act as "low-pass" filters, removing high-frequency seasonal noise and responding to longer-term trends in pelagic ecosystem structure and export production. We propose to conduct a 3-year study of bentho-pelagic coupling along a latitudinal climate gradient on the Antarctic Peninsula to explore the potential impacts of climate change (e.g., reduction in sea-ice duration) on Antarctic shelf ecosystems. We will conduct three cruises during summer and winter regimes along a 5- station transect from Smith Island to Marguerite Bay, evaluating a broad range of benthic ecological and biogeochemical processes. Specifically, we will examine the feeding strategies of benthic deposit feeders along this climatic gradient to elucidate the potential response of this major trophic group to climatic warming. In addition, we will (1) quantify carbon and nitrogen cycling and burial at the seafloor and (2) document changes in megafaunal, macrofaunal, and microbial community structure along this latitudinal gradient. We expect to develop predictive insights into the response of Antarctic shelf ecosystems to some of the effects of climate warming (e.g., a reduction in winter sea-ice duration). The proposed research will considerably broaden the ecological and carbon-flux measurements made as parts of the Palmer Station LTER and GLOBEC programs by providing a complementary benthic component. This project also will promote science education from the 9th grade to graduate-student levels. We will partner with the NSF-sponsored Southeastern Center for Ocean Science Education Excellence to reach students of all races in all areas of NC, SC and GA. The project will also benefit students at the post secondary level by supporting three graduate and two undergraduate students. During each of the three field excursions, NCSU and UH students will travel to Chile and Antarctica to participate in scientific research. Lastly, all three PIs will incorporate material from this project into their undergraduate and graduate courses. | POLYGON((-71.2358 -52.7603,-69.75336 -52.7603,-68.27092 -52.7603,-66.78848 -52.7603,-65.30604 -52.7603,-63.8236 -52.7603,-62.34116 -52.7603,-60.85872 -52.7603,-59.37628 -52.7603,-57.89384 -52.7603,-56.4114 -52.7603,-56.4114 -54.29969,-56.4114 -55.83908,-56.4114 -57.37847,-56.4114 -58.91786,-56.4114 -60.45725,-56.4114 -61.99664,-56.4114 -63.53603,-56.4114 -65.07542,-56.4114 -66.61481,-56.4114 -68.1542,-57.89384 -68.1542,-59.37628 -68.1542,-60.85872 -68.1542,-62.34116 -68.1542,-63.8236 -68.1542,-65.30604 -68.1542,-66.78848 -68.1542,-68.27092 -68.1542,-69.75336 -68.1542,-71.2358 -68.1542,-71.2358 -66.61481,-71.2358 -65.07542,-71.2358 -63.53603,-71.2358 -61.99664,-71.2358 -60.45725,-71.2358 -58.91786,-71.2358 -57.37847,-71.2358 -55.83908,-71.2358 -54.29969,-71.2358 -52.7603)) | POINT(-63.8236 -60.45725) | false | false | ||||||||||||||
Interannual Variability in the Antarctic-Ross Sea (IVARS): Nutrients and Seasonal Production
|
0087401 |
2010-05-04 | Smith, Walker; Gordon, Arnold | 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. | None | None | false | false | ||||||||||||||
Management and Scientific Service in Support of the U.S. JGOFS Southern Ocean Process Study: Hydrography, Coring and Site Survey
|
9530398 9530382 9896290 |
2010-05-04 | Anderson, Robert; Smith, Walker; Honjo, Susumu |
|
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. | 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)) | POINT(0 -89.999) | false | false | |||||||||||||
Collaborative Research: Interactive Effects of Iron, Light and CO2 on Phytoplankton Community Dynamics in the Ross Sea
|
0338164 |
2010-05-04 | Ditullio, Giacomo |
|
The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. <br/>This project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images. | None | None | false | false | |||||||||||||
Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial forms of Phaeocystis antarctica
|
0440478 |
2009-05-04 | Tang, Kam; Smith, Walker |
|
Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:<br/>o Do P. Antarctica solitary cells and colonies differ in growth, composition and<br/>photosynthetic rates?<br/>o How do nutrients and grazers affect colony development and size distribution of P. <br/>Antarctica?<br/>o How do nutrients and grazers act synergistically to affect the long-term population<br/>dynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience. | POINT(166.66267 -77.85067) | POINT(166.66267 -77.85067) | false | false | |||||||||||||
Collaborative Research: Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island
|
0338342 0338260 |
2009-03-16 | Foreman, Christine; Chin, Yu-Ping |
|
Dissolved organic matter (DOM) is a significant chemical component in aquatic systems because it acts as an important carbon source for microorganisms, absorbs harmful radiation in sunlight, is able to complex metals, and can participate in important biogeochemical reactions. This study will investigate the biogeochemical cycling of DOM in a small coastal Antarctic pond, Pony Lake, located on Cape Royds, Ross Island. Because there are no higher plants present at this site all of the DOM in this lake is derived from microorganisms. Thus, Pony Lake is an ideal site to study the effect of physical, chemical, and microbial processes on the composition and character of the DOM pool. Finally, Pony Lake is also an ideal site to collect an International Humic Substances Society (IHSS) fulvic acid standard. Unlike other IHSS standards, this standard will not contain DOM components derived from higher land plants. To better understand the role of physical influences, the project will study the changes in the DOM pool as the lake evolves from ice-covered to ice-free conditions during the summer, as well as the relationship of DOM to the observed turnover of dominant microbial communities in the lake. Scientists will also monitor changes in microbial abundance, diversity, and productivity that may occur during the ice to open-water transition period. This research will provide much needed information regarding the relationship between microbial diversity and DOM biogeochemistry. Middle school science students will be active participants in this project through the Internet, while scientists are in the field, and in the lab. | POINT(166.167 -77.55) | POINT(166.167 -77.55) | false | false | |||||||||||||
SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions
|
0742057 |
2009-03-16 | Gallager, Scott; Dennett, Mark |
|
Abstract<br/><br/>The research will continue and extend the study in the Southern Ocean that was initiated during the Oden Southern Ocean 2006 expedition in collaboration with Swedish scientist Mellissa Chierici. We will quantify carbon flux through the food web in the marginal ice zone (MIZ) by measuring size fractionated primary and secondary production, grazing and carbon flux through nanoplankton (2-20 um), microplankton (20-200um), and mesoplankton (200-2000 um). Community structure, species abundance and size specific grazing rates will be quantified using a variety of techniques both underway and at ice stations along the MIZ. The proposed cruise track extends across the Drake Passage to the Western Antarctic Peninsula (WAP) with three station transects along a gradient from the open ocean through the marginal ice zone (MIZ) in the Bellinghausen and Amundsen Seas and into the Ross Sea Polynya. Ice stations along each transect will provide material to characterize production associated with annual ice. Underway measurements of primary and secondary production (chlorophyll, CDOM, microplankton, and mesoplankton) and hydrography (temperature, salinity, pH, DO, turbidity) will establish a baseline for future cruises and as support for other projects such as biogeochemical studies on carbon dioxide drawdown and trace metal work on primary production. The outcome of these measurements will be a description of nano to mesoplankton standing stocks, community structure, and carbon flux along the MIZ in the Bellinghausen and Amundsen Seas and the Ross Sea Polynya. | POLYGON((-168.291 -64.846,-165.018 -64.846,-161.745 -64.846,-158.472 -64.846,-155.199 -64.846,-151.926 -64.846,-148.653 -64.846,-145.38 -64.846,-142.107 -64.846,-138.834 -64.846,-135.561 -64.846,-135.561 -66.0269,-135.561 -67.2078,-135.561 -68.3887,-135.561 -69.5696,-135.561 -70.7505,-135.561 -71.9314,-135.561 -73.1123,-135.561 -74.2932,-135.561 -75.4741,-135.561 -76.655,-138.834 -76.655,-142.107 -76.655,-145.38 -76.655,-148.653 -76.655,-151.926 -76.655,-155.199 -76.655,-158.472 -76.655,-161.745 -76.655,-165.018 -76.655,-168.291 -76.655,-168.291 -75.4741,-168.291 -74.2932,-168.291 -73.1123,-168.291 -71.9314,-168.291 -70.7505,-168.291 -69.5696,-168.291 -68.3887,-168.291 -67.2078,-168.291 -66.0269,-168.291 -64.846)) | POINT(-151.926 -70.7505) | false | false | |||||||||||||
SGER: Science-of-Opportunity Aboard Icebreaker Oden: Bioactive trace metals in the Amundsen and Ross Seas
|
0741403 |
2009-03-10 | Sherrell, Robert | No dataset link provided | Abstract<br/><br/>The research objective is (1) to determine the distributions and dynamics of a full suite of bioactive trace metals in dissolved and suspended particulate forms, along sampling transects of the Amundsen and Ross Seas. And (2) to test the sensitivity of overall cellular metal stoichiometry (metal/carbon ratios) to natural gradients in species assemblage and Fe availability. Our earlier findings from a single Ross Sea station and from a Drake Passage crossing suggest that Fe-limited phytoplankton cells are unusually enriched in Zn, Cu and Cd relative to biomass carbon, with strong implications for the biogeochemical cycling of these elements relative to carbon fluxes in the Southern Ocean. In collaboration with other researchers on the cruise, we will also measure metal stoichiometry of cells exposed to predicted 2010 temperature and carbon dioxide levels in shipboard incubation studies, as a window into possible effects of climate change on metals biogeochemistry in these regions. This proposal will support close international collaborations and lasting infrastructure development as US and Swedish scientists, and more importantly, their students, work toward shared the shared goal of understanding a region that is experiencing one of the fastest rates of climate change on the globe. Trace metal micro-nutrients are a key control on the productivity of Antarctic marine ecosystems. Our results will be made widely available through research publications and internet-available databases, and public outreach through COSEE at Rutgers University. | POLYGON((-180 -69,-172.5 -69,-165 -69,-157.5 -69,-150 -69,-142.5 -69,-135 -69,-127.5 -69,-120 -69,-112.5 -69,-105 -69,-105 -69.9,-105 -70.8,-105 -71.7,-105 -72.6,-105 -73.5,-105 -74.4,-105 -75.3,-105 -76.2,-105 -77.1,-105 -78,-112.5 -78,-120 -78,-127.5 -78,-135 -78,-142.5 -78,-150 -78,-157.5 -78,-165 -78,-172.5 -78,180 -78,178.8 -78,177.6 -78,176.4 -78,175.2 -78,174 -78,172.8 -78,171.6 -78,170.4 -78,169.2 -78,168 -78,168 -77.1,168 -76.2,168 -75.3,168 -74.4,168 -73.5,168 -72.6,168 -71.7,168 -70.8,168 -69.9,168 -69,169.2 -69,170.4 -69,171.6 -69,172.8 -69,174 -69,175.2 -69,176.4 -69,177.6 -69,178.8 -69,-180 -69)) | POINT(-148.5 -73.5) | false | false | |||||||||||||
Distribution And Ecology Of Ammonia Oxidizing Bacteria In The Palmer LTER Study Area
|
0234249 |
2008-12-01 | Hollibaugh, James T. |
|
This project will investigate the distribution, phylogenetic affinities and ecological aspects of ammonium-oxidizing bacteria in the Palmer Long-Term Ecological Research study area. Ammonia oxidation is the first step in the conversion of regenerated nitrogen to dinitrogen gas via denitrification, a 3-step pathway mediated by three distinct guilds of bacteria. As such, ammonia oxidation is important to the global nitrogen cycle. Ammonia oxidation and the overall process of nitrification-denitrification have received little attention in polar oceans where it is significant and where the effects of climate change on biogeochemical rates are likely to be pronounced. The goals of the studies proposed here are A) to obtain more conclusive information concerning composition of Antarctic ammonia oxidizers; B) to begin characterizing their ecophysiology and ecology; and C) to obtain cultures of the organism for more detailed studies. Water column and sea ice AOB assemblages will be characterized phylogenetically and the different kinds of AOB in various samples will be quantified. Nitrification rates will be measured across the LTER study area in water column, sea ice and sediment samples. Grazing rates on AOB will be determined and their sensitivity to UV light evaluated. In addition, the significance of urea nitrogen as a source of reduced nitrogen to AOB will be assessed and the temperature response of nitrification over temperature ranges appropriate to polar regions will be evaluated. This work will provide insights into the ecology of AOB and the knowledge needed to model how water column nitrification will respond to changes in the polar ecosystems accompanying global climate change. | POLYGON((-73 -64,-72.1 -64,-71.2 -64,-70.3 -64,-69.4 -64,-68.5 -64,-67.6 -64,-66.7 -64,-65.8 -64,-64.9 -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,-64.9 -68,-65.8 -68,-66.7 -68,-67.6 -68,-68.5 -68,-69.4 -68,-70.3 -68,-71.2 -68,-72.1 -68,-73 -68,-73 -67.6,-73 -67.2,-73 -66.8,-73 -66.4,-73 -66,-73 -65.6,-73 -65.2,-73 -64.8,-73 -64.4,-73 -64)) | POINT(-68.5 -66) | false | false | |||||||||||||
Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores
|
0636953 |
2008-10-22 | Saltzman, Eric; Aydin, Murat; Williams, Margaret | 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). | POINT(-148.82 -81.66) | POINT(-148.82 -81.66) | false | false | ||||||||||||||
Collaborative Research: Hydrologic Controls over Biogeochemistry and Microbial Community Structure and Function across Terrestrial/Aquatic Interfaces in a Polar Desert
|
0338267 |
2008-09-11 | Gooseff, Michael N.; Barrett, John; Takacs-Vesbach, Cristina |
|
Aquatic-terrestrial transition zones are crucial environments in understanding the biogeochemistry of landscapes. In temperate watersheds, these areas are generally dominated by riparian zones, which have been identified as regions of special interest for biogeochemistry because of the increased microbial activity in these locations, and because of the importance of these hydrological margins in facilitating and buffering hydrologic and biogeochemical exchanges between terrestrial and aquatic ecosystems. In the Antarctic Dry Valleys, terrestrial-aquatic transition zones are intriguing landscape features because of the vast importance of water in this polar desert, and because the material and energy budgets of dry valley ecosystems are linked by hydrology. Hydrological margins in aquatic-terrestrial transition zones will be studied in the Dry Valleys of Antarctica to answer two overarching questions: (1) what are the major controls over hydrologic and biogeochemical exchange across aquaticterrestrial transition zones and (2) to what extent do trends in nutrient cycling (e.g. nitrogen cycling) across these transition zones reflect differences in microbial communities or function vs. differences in the physical and chemical environment (e.g., redox potential)? The hydrologic gradients that define these interfaces provide the opportunity to assess the relative influence of physical conditions and microbial biodiversity and functioning upon biogeochemical cycling. Coordinated hydrologic, biogeochemical, and molecular microbial studies will be executed within hydrologic margins with the following research objectives: to determine the role of sediment characteristics, permafrost and active layer dynamics, and topography on sub-surface water content and distribution in hydrologic margins, to determine the extent to which transformations of nitrogen in hydrological margins are influenced by physical conditions (i.e., moisture, redox potential and pH) or by the presence of specific microbial communities (e.g., denitrifiers), and to characterize the microbial community structure and function of saturated zones.<br/><br/>This proposed research will provide an improved understanding of the interaction of liquid water, soils, microbial communities, and biogeochemistry within the important hydrologic margin landscape units of the dry valleys. Dry valleys streams and lakes are unique because there is no influence of higher vegetation on the movement of water and may therefore provide a model system for understanding physical and hydrological influences on microbial ecology and biogeochemistry. Hence the findings will contribute to Antarctic science as well as the broader study of riparian zones and hydrologic margins worldwide. Graduate students and undergraduate students will be involved with fieldwork and research projects. Information will be disseminated through a project web site, and outreach activities will include science education in local elementary, middle and high schools near the three universities involved. | POLYGON((161.6 -77.4,161.773 -77.4,161.946 -77.4,162.119 -77.4,162.292 -77.4,162.465 -77.4,162.638 -77.4,162.811 -77.4,162.984 -77.4,163.157 -77.4,163.33 -77.4,163.33 -77.435,163.33 -77.47,163.33 -77.505,163.33 -77.54,163.33 -77.575,163.33 -77.61,163.33 -77.645,163.33 -77.68,163.33 -77.715,163.33 -77.75,163.157 -77.75,162.984 -77.75,162.811 -77.75,162.638 -77.75,162.465 -77.75,162.292 -77.75,162.119 -77.75,161.946 -77.75,161.773 -77.75,161.6 -77.75,161.6 -77.715,161.6 -77.68,161.6 -77.645,161.6 -77.61,161.6 -77.575,161.6 -77.54,161.6 -77.505,161.6 -77.47,161.6 -77.435,161.6 -77.4)) | POINT(162.465 -77.575) | false | false | |||||||||||||
Collaborative Proposal: Interactive Effects of UV Radiation and Vertical Mixing on Phytoplankton and Bacterial Productivity of Ross See Phaeocystis Blooms
|
0127022 |
2008-06-12 | Jeffrey, Wade H.; Neale, Patrick |
|
Ultraviolet radiation influences the dynamics of plankton processes in the near-surface waters of most aquatic ecosystems. In particular, the Southern Ocean is affected in the austral spring period when biologically damaging ultraviolet radiation is enhanced by ozone depletion. While progress has been made in estimating the quantitative impact of ultraviolet radiation on bacteria and phytoplankton in the Southern Ocean, some important issues remain to be resolved. Little is known about responses in systems dominated by the colonial haptophyte Phaeocystis antarctica, which dominates spring blooms in a polyna that develops in the southern Ross Sea. The Ross Sea is also of interest because of the occurrence of open water at a far southerly location in the spring, well within the ozone hole, and continuous daylight, with implications for the regulation of DNA repair. A number of studies suggest that vertical mixing can significant modify the impact of ultraviolet radiation in the Southern Ocean and elsewhere. However, there are limited measurements of turbulence intensity in the surface layer and measurements have not been integrated with parallel studies of ultraviolet radiation effects on phytoplankton and bacterioplankton. To address these issues, this collaborative study will focus on vertical mixing and the impact of ultraviolet radiation in the Ross Sea. The spectral and temporal responses of phytoplankton and bacterioplankton to ultraviolet radiation will be characterized in both laboratory and solar incubations. These will lead to the definition of biological weighting functions and response models capable of predicting the depth and time distribution of ultraviolet radiation impacts on photosynthesis, bacterial incorporation and DNA damage in the surface layer. Diel sampling will measure depth-dependent profiles of DNA damage, bacterial incorporation, photosynthesis and fluorescence parameters over a 24 h cycle. Sampling will include stations with contrasting wind-driven mixing and stratification as the polyna develops. The program of vertical mixing measurements is optimized for the typical springtime Ross Sea situation in which turbulence of intermediate intensity is insufficient to mix the upper layer thoroughly in the presence of stabilizing influences like solar heating and/or surface freshwater input from melting ice. Fine-scale vertical density profiles will be measured with a free-fall CTD unit and the profiles will be used to directly estimate large-eddy scales by determining Thorpe scales. Eddy scales and estimated turbulent diffusivities will be directly related to surface layer effects, and used to generate lagrangian depth-time trajectories in models of ultraviolet radiation responses in the surface mixed layer. The proposed research will be the first in-depth study of ultraviolet radiation effects in the Ross Sea and provide a valuable comparison with previous work in the Weddell-Scotia Confluence and Palmer Station regions. It will also enhance the understanding of vertical mixing processes, trophic interactions and biogeochemical cycling in the Ross Sea. | POLYGON((-177.639 -43.5676,-143.1091 -43.5676,-108.5792 -43.5676,-74.0493 -43.5676,-39.5194 -43.5676,-4.9895 -43.5676,29.5404 -43.5676,64.0703 -43.5676,98.6002 -43.5676,133.1301 -43.5676,167.66 -43.5676,167.66 -46.99877,167.66 -50.42994,167.66 -53.86111,167.66 -57.29228,167.66 -60.72345,167.66 -64.15462,167.66 -67.58579,167.66 -71.01696,167.66 -74.44813,167.66 -77.8793,133.1301 -77.8793,98.6002 -77.8793,64.0703 -77.8793,29.5404 -77.8793,-4.9895 -77.8793,-39.5194 -77.8793,-74.0493 -77.8793,-108.5792 -77.8793,-143.1091 -77.8793,-177.639 -77.8793,-177.639 -74.44813,-177.639 -71.01696,-177.639 -67.58579,-177.639 -64.15462,-177.639 -60.72345,-177.639 -57.29228,-177.639 -53.86111,-177.639 -50.42994,-177.639 -46.99877,-177.639 -43.5676)) | POINT(-4.9895 -60.72345) | false | false | |||||||||||||
Constructing Paleoatmospheric Records of the Isotopic Composition of Methane and Nitrous Oxide
|
9526556 |
2007-07-09 | Sowers, Todd A. |
|
This award is for support for a program to reconstruct records of the isotopic composition of paleoatmospheric methane and nitrous oxide covering the last 200,000 years. High resolution measurements of the carbon-13 isotopic composition of methane from shallow ice cores will help to determine the relative contributions of biogenic (wetlands, rice fields and ruminants) and abiogenic (biomass burning and natural gas) methane emissions which have caused the concentrations of this gas to increase at an exponential rate during the anthropogenic period. Isotopic data on methane and nitrous oxide over glacial/interglacial timescales will help determine the underlying cause of the large concentration variations that are known to occur. This project will make use of a new generation mass spectrometer which is capable of generating precise isotopic information on nanomolar quantities of methane and nitrous oxide, which means that samples can be 1000 times smaller than those needed for a standard isotope ratio instrument. The primary objective of the work is to further our understanding of the biogeochemical cycles of these two greenhouse gases throughout the anthropogenic period as well as over glacial interglacial timescales. | POINT(-148.3023 -81.403) | POINT(-148.3023 -81.403) | false | false | |||||||||||||
Collaborative Research: Digital Optical Imaging of Ice Cores for Curation and Scientific Applications
|
0230149 |
2007-06-04 | McGwire, Kenneth C. | No dataset link provided | This award supports the development of novel methods for digital image analysis of glacial ice cores that are stored at the National Ice Core Laboratory (NICL) in Denver, Colorado. Ice cores are a critical source of information on how Earth has changed over time, since indicators of local climate (snow accumulation, temperature), regional characteristics (wind-blown materials such as sea salt, dust and pollen), global processes (e.g., CO2, methane), and even extraterrestrial influences (cosmogenic isotopes) are stored in the ice on a common time scale. This project will develop a high-resolution optical scanning system for laboratory curation of ice core images, internet-based search and retrieval capabilities, a digital image analysis system specifically for ice core studies, and methods to integrate ice core image analysis with other dating methods. These tools will be developed and tested in conjunction with scientific investigations of NICL holdings. Optical scanning and analysis tools will improve understanding of the historical development of the ice collected from a particular location and will help to resolve challenges such as ice that has lost stratigraphic order through flow processes. <br/>By providing permanent online digital archives of ice core images, this project will greatly improve the documentation and availability of ice core data while reducing time and costs for subsequent scientific investigations. Using the internet, ice core scientists will be able to determine the appropriateness of specific NICL holdings for various scientific studies. By optically scanning ice cores as they are processed at NICL, any researcher will be able to examine an ice core in similar detail to the few investigators who were fortunate enough to observe it before modifications from sampling and storage. Re-examination of cores could be done decades later by anyone at any location, which is not possible now because only the interpretation of the original observer is recorded. Integration of digital image data into ice core analysis will speed discovery, allow collaborative interpretation, and enhance consistency of analysis to improve ice core dating, identification of melt layers, location of flow disturbances, and more. The equipment will be housed at NICL and will be available to the broad community, improving scientific infrastructure.<br/>This work will also have numerous broader impacts. Ice core science addresses fundamental questions of human interest related to global warming, abrupt climate change, biogeochemical cycling, and more. The principal investigators broadly disseminate their scientific findings through numerous outlets, ranging from meeting with government officials, chairing and serving on NRC panels, writing popular books and articles, publishing in scientific literature, teaching classes, talking to civic groups, and appearing on radio and television. The results from ice core analyses have directly informed policymakers and will continue to do so. Thus, by improving ice core science, this projectl will benefit society. | None | None | false | false | |||||||||||||
Methyl chloride and methyl bromide in Antarctic ice cores
|
0338359 |
2005-11-16 | Saltzman, Eric; Aydin, Murat; Williams, Margaret; Tatum, Cheryl | 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. | POINT(-148.81 -81.65) | POINT(-148.81 -81.65) | false | false | ||||||||||||||
Constructing the first D/H record of atmospheric methane covering the last two centuries.
|
0125900 |
2005-05-26 | Sowers, Todd A. | No dataset link provided | 0125900<br/>Sowers<br/><br/>This award supports a project to improve the understanding of the biogeochemical processes that control CH4 emissions. Records of the concentration of methane in trapped gases in ice tell us about changes in atmospheric loading through time. Such records do not, however, provide information on the individual sources or sinks. One way to refine our understanding of the cycling of bioactive trace gases like methane is to use stable isotope records of trapped gases in ice cores. This project will measure the Deuterium/Hydrogen (D/H) ratio of methane trapped in shallow/recent ice (covering the last ~ 200 years) at Siple Dome, Antarctica. The proposed work will complement current efforts to measure the carbon-13 isotope ratio of methane in ice cores and will provide fundamental information on the various sources and sinks of atmospheric methane over the last 200 years. | POINT(-148.8 -81.7) | POINT(-148.8 -81.7) | false | false | |||||||||||||
Generating an Isotopic Record of Atmospheric Methane and Nitrous Oxide Over the Last Century from South Pole Firn Air
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0125981 |
2005-05-05 | Sowers, Todd A. | No dataset link provided | 0125981<br/>Sowers<br/><br/>This award supports a project to construct an isotopic record of atmospheric methane and nitrous oxide over the last century from South Pole firn air. Over the last 150 years, atmospheric methane and nitrous oxide concentrations have risen in response to increased emissions from various anthropogenic activities. As this trend is liable to continue in the foreseeable future, it is important to understand the biogeochemical processes that contribute to the emissions of these two greenhouse gases. In this context, records of the variations in the atmospheric loading of trace gases found in ice cores and interstitial spaces in the snow near the surface of the ice sheet (firn air) provide fundamental boundary conditions for reconstructing historical emission records. One way to improve our understanding of the cycling of bioactive trace gases and their emission records is to use stable isotope tracers, which have been recorded in the ice cores and firn air. This project will develop records of carbon-13 and deuterium isotope ratios of methane, as well as the nitrogen-15, oxygen-18 and the isotopomer composition of nitrous oxide trapped in firn air samples collected in January 2001 at the South Pole. These measurements will allow isotopic records of these atmospheric gases to be reconstructed throughout the 20th century. Such records will help to establish the relative contribution of individual sources with a higher degree of confidence than is currently available. | POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83)) | POINT(0 -89.999) | false | false | |||||||||||||
Proxies of Past Changes in Southern Ocean Productivity: Modeling and Experimental Development
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9530379 |
1970-01-01 | Anderson, Robert |
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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. *** | 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)) | POINT(0 -89.999) | false | false |