[{"awards": "2420219 Chignell, Stephen", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "Geodiversity is the variety of non-living elements like rocks, landforms, and processes in a given area, and plays an especially critical role in Antarctica. Geodiversity provides the conditions in which life can develop and underpins all ecosystems on Earth. It also provides tangible services to people (like construction materials) as well as intangible benefits (such as scientific knowledge from ice cores and artistic inspiration from glaciers). Despite its importance, Antarctic geodiversity remains under-explored, under-described, and inadequately mapped. This knowledge gap is particularly concerning given the threats posed by increasing human activity and environmental and climate change. This project uses a variety of datasets to map Antarctic geodiversity, assess its benefits to people, and help identify priority locations for conservation. \u003cbr/\u003e\u003cbr/\u003eThrough an interdisciplinary and mixed-method approach, this research will fill a major gap in the current understanding and representations of the Antarctic. Using the McMurdo Dry Valleys as a case study, the researcher will combine geospatial data on geology, geomorphology, glaciology, and hydrology to map geodiversity of the region. This project will identify sites of key geosystem services by analyzing geospatial data on placenames, scientific samples, and a web-based participatory mapping survey. The geodiversity and geosystem services data will then be overlaid and combined to identify hotspots of geo-social diversity. The resulting maps will be compared with the region\u2019s protected area boundaries to assess the fit-for-purpose of current environmental management and identify priority locations for future research and conservation. The fellow will promote Antarctic geodiversity broadly, including at UNESCO International Geodiversity Day.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "McMurdo Dry Valleys; LANDSCAPE; ROCKS/MINERALS/CRYSTALS; LANDFORMS; GIS; GLACIAL LANDFORMS; RIVERS/STREAMS", "locations": "McMurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Chignell, Stephen", "platforms": null, "repositories": null, "science_programs": null, "south": -78.5, "title": "Postdoctoral Fellowship: OPP-PRF: Mapping Antarctic Geodiversity: Assessing People, Place, and Abiotic Nature in the McMurdo Dry Valleys", "uid": "p0010476", "west": 160.0}, {"awards": "2336354 Juarez Rivera, Marisol", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": "Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae", "datasets": [{"dataset_uid": "601839", "doi": null, "keywords": "Antarctica; Cryosphere; Dry Valleys; Lake Fryxell; Laminae; Microbial Mat; Thickness", "people": "Paul, Ann; Sumner, Dawn; Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian", "repository": "USAP-DC", "science_program": null, "title": "Lake Fryxell 2022-2023 benthic microbial mat thickness and number of laminae", "url": "https://www.usap-dc.org/view/dataset/601839"}], "date_created": "Fri, 05 Jul 2024 00:00:00 GMT", "description": "Perennially ice-covered lakes in the McMurdo Dry Valleys of Antarctica contain abundant microbial mats, and the export of this mat material can fertilize the surrounding polar desert ecosystems. These desert soils are one of the most organic-poor on earth yet host a community of microorganisms. Microbial mat material is exported from the shallow, gas-supersaturated regions of the lakes when gas bubbles form in the mats, lifting them to the ice cover. The perennial ice cover maintains gas supersaturation. These mats freeze in and are exported to the surrounding soils through ice ablation. The largest seasonal decrease and thinnest ice cover in the history of Lake Fryxell was recorded during the 2022-2023 Austral summer. In this thin ice year, the water column dissolved oxygen increased over prior observations, and the lake bottom surface area with bubble-disrupted mat was more than double that observed in 1980-1981 and 2006-2007. This work will constrain mat mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning to understand how future changing regional climate and predicted seasonal loss of lake ice cover will affect nutrient transport in the McMurdo Dry Valleys. Exceptional years of mat export are hypothesized to have the most significant impact on nutrient export to soil communities. Variability in mat liftoff may thus play a role in the McMurdo Dry Valleys ecosystem response to changing climate. The perennial ice cover of lakes in the McMurdo Dry Valleys of Antarctica modulates the transfer of gasses, organic and inorganic material, between the lakes and surrounding soils. The export of biomass in these lakes is driven by the supersaturation of atmospheric gasses in the shallow regions under perennial ice cover. Gas bubbles nucleate in the mats, producing buoyancy that lifts them to the bottom of the ice, where they freeze in and are exported to the surrounding soils through ice ablation. These mats represent a significant source of biomass and nutrients to the McMurdo Dry Valleys soils, which are among the most organic-poor on earth. Nevertheless, this biomass remains unaccounted for in organic carbon cycling models for the McMurdo Dry Valleys. Ice cover data from the McMurdo Dry Valleys Long Term Ecological Research Project shows that the ice thickness has undergone cyclical variation over the last 40 years, reaching the largest seasonal decrease and thinnest ice-cover in the recorded history of Lake Fryxell during the 2022-2023 austral summer. Preliminary work shows that the surface area with mat liftoff at Lake Fryxell is more than double that observed in 1980-1981 and 2006-2007, coinciding with this unprecedented thinning of the ice-cover and an increase in the water column dissolved O2. This research will constrain biomass mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning. The researchers hypothesize that a thinner ice cover promotes more biomass mobilization by 1) stimulating additional production of gas bubbles from the existing gas-supersaturated waters during summertime photosynthesis to create microbial mat liftoff and 2) promoting mat liftoff in deeper, thicker microbial mats, and 3) that this biomass can be traced into the soils by characterizing its chemistry and modeling the most likely depositional settings. This work will use microbial mat samples, lake dissolved oxygen and photosynthetically active radiation data and underwater drone footage documenting the depth distribution of liftoff mats in January 2023, and long-term ice cover thickness, photosynthetically active radiation, and lake level change data collected by the McMurdo Dry Valleys Long Term Ecological Research Project to test hypotheses 1-3. The dispersal of the liftoff mat exposed at Lake Fryxell surface will be modeled using a Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Exceptional liftoff years like the present are hypothesized to have the most significant impact on the soil communities as the rates of soil respiration increase with the addition of carbon. However, continued warming in the next 10 - 40 years may result in seasonal loss of the ice cover and cessation of liftoff mat export.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Stable Isotopes; MINERALS; LAKE/POND; ISOTOPES; Organic Matter; McMurdo Dry Valleys; SEDIMENTARY ROCKS", "locations": "McMurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Juarez Rivera, Marisol", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "RAPID: Is Biomass Mobilization at Ice-covered Lake Fryxell, Antarctica reaching a Critical Threshold?", "uid": "p0010467", "west": 160.0}, {"awards": "1444690 Bell, Robin; 0958658 Bell, Robin", "bounds_geometry": null, "dataset_titles": "Deep ICE (DICE) Radar Dataset from Ross Ice Shelf (ROSETTA-Ice); Shallow Ice Radar (SIR) Dataset from Ross Ice Shelf (ROSETTA-Ice)", "datasets": [{"dataset_uid": "601794", "doi": null, "keywords": "Antarctica; Cryosphere; Remote Sensing; Ross Ice Shelf", "people": "Wearing, Martin; Das, Indrani; Bell, Robin; Dong, LingLing; Chu, Winnie; Packard, Sarah; Spergel, Julian; Keeshin, Skye; Cordero, Isabel; Frearson, Nicholas; Dhakal, Tejendra; Bertinato, Christopher", "repository": "USAP-DC", "science_program": null, "title": "Shallow Ice Radar (SIR) Dataset from Ross Ice Shelf (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601794"}, {"dataset_uid": "601789", "doi": null, "keywords": "Airborne Radar; Antarctica; Cryosphere; Ice Thickness; Remote Sensing; Ross Ice Shelf", "people": "Bertinato, Christopher; Wilner, Joel; Dong, LingLing; Bell, Robin; Frearson, Nicholas; Dhakal, Tejendra; Millstein, Joanna; Chu, Winnie; Spergel, Julian; Das, Indrani; Cordero, Isabel", "repository": "USAP-DC", "science_program": null, "title": "Deep ICE (DICE) Radar Dataset from Ross Ice Shelf (ROSETTA-Ice)", "url": "https://www.usap-dc.org/view/dataset/601789"}], "date_created": "Fri, 17 May 2024 00:00:00 GMT", "description": "The Lamont-Doherty Earth Observatory of Columbia University was awarded a multi-year grant (May 1, 2010- April 30, 2015) to develop an ice imaging system, or \"IcePod,\" for use in measuring the surface and subsurface topography of ice sheets. IcePod will enable research on the effects of global climate change on ice sheets and the effects of sub-glacial water on potential sea-level rise. IcePod sensors are contained in a Common Science Support Pod and operated on NYANG LC-130 aircraft during routine and targeted missions over Greenland and Antarctica. The IcePod instrument package consists of ice-penetrating radar, infrared and visible cameras, laser altimeter, inertial measurement unit, GPS receiver and data acquisition system. IcePod will also enable other instruments to be used in the modular Common Science Support Pod, and will become a shared community research facility providing data to the science community. Funding will support activities in both Greenland and Antarctica needed to commission IcePod, to develop a data reduction flow and data delivery system for IcePod data, and to engineer a UPS to provide IcePod with clean, reliable power for system operation. \u003cbr/\u003e\u003cbr/\u003eEvidence from satellites has documented that the amount of ice in both the earth\u0027s polar regions is decreasing as global temperatures increase. Understanding how this change is occurring and building an understanding of how fast these continent-sized pieces of ice will change in the future, is critical as society develops plans for adapting to changing coastlines. To measure change and understand the processes driving these changes requires the capacity to image the polat ice sheets and oceans from long-range aircraft. This award supplemented the original MRI-R2 program that developed innovative airborne imagery technology called IcePod. IcePod can be mounted on any LC-130, the aircraft used in the polar regions, for the major logistical support. The IcePod system was developed by engineers and scientists at Columbia University, working in close collaboration with the New York Air National Guard, who operate the ski-equipped LC-130 aircraft for the National Science Foundation in Antarctica and Greenland. The IcePod instrumentation package presently consists of: a scanning laser for precise measurements of the ice surface, visible and infrared imaging cameras to document the ice surface structure and temperature, ice-penetrating radar to recover the ice thickness and constrain the distribution of water at the ice sheet bed, and shallow-ice radar to measure snow accumulation. A magnetometer system is mounted inside the pod to recover information on the solid earth structure. Positioning of the IcePod during flights and the measurements are provided by precision GPS satellite data and inertial technology. A gravimeter, using its own rack, is also employed in conjunction with the IcePod sensor suite. The final commissioning of the system occurred in November - December 2014 in Antarctica as stipulated in the award. The IcePod was successfully operated in full polar conditions with a series of flights from McMurdo Station over the Ross Ice Shelf, the Ross Sea, the Dry Valleys, the Transantarctic Mountains and to South Pole. Protocol was also developed for data handling, robust data reduction, workflow and quality control and archiving of data. \u003cbr/\u003e\u003cbr/\u003eThe system is now available to the polar community for novel imaging applications.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Greenland; C-130; Remote Sensing; RADAR; GLACIERS/ICE SHEETS; Antarctica", "locations": "Antarctica; Greenland", "north": null, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences; Antarctic Instrumentation and Support; Antarctic Instrumentation and Support; Antarctic Earth Sciences; Antarctic Integrated System Science", "paleo_time": null, "persons": "Bell, Robin; Frearson, Nicholas; Zappa, Christopher; Studinger, Michael S.", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e C-130", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Development of an Ice Imaging System for Monitoring Changing Ice Sheets Mounted on the NYANG LC-130", "uid": "p0010462", "west": null}, {"awards": "2044924 Barrett, John", "bounds_geometry": null, "dataset_titles": "Hyperspectral reflectance values and biophysicochemical properties of biocrusts and soils in the Fryxell Basin, McMurdo Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "601773", "doi": "10.15784/601773", "repository": "USAP-DC", "science_program": null, "title": "Hyperspectral reflectance values and biophysicochemical properties of biocrusts and soils in the Fryxell Basin, McMurdo Dry Valleys, Antarctica", "url": "http://www.usap-dc.org/view/dataset/601773"}], "date_created": "Wed, 03 Apr 2024 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Carbon; Cryosphere; McMurdo Dry Valleys; Snow", "locations": "McMurdo Dry Valleys; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Barrett, John", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"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 Integrated System Science; Antarctic Organisms and Ecosystems", "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": "2137375 Schmidt, Steven; 2137378 Varsani, Arvind; 2137377 Bergstrom, Anna; 2137376 Porazinska, Dorota", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 10 May 2023 00:00:00 GMT", "description": "Cryoconite holes are sediment-filled melt holes in the surface of glaciers that can be important sites of active microbial life in an otherwise mostly frozen and barren landscape. Previous studies in the McMurdo Dry Valleys, Antarctica suggest that viral infections of microbes, and a general lack of fertilizers (i.e., nutrients), may be important factors shaping the development and functioning of microbial communities in cryoconite holes. The researchers propose an experimental approach to understand how nutrient limitation affects diversity (number of species) and overall abundance of microbes, and how the diversity and abundance of microbes in turn affects the diversity, abundance, and infection type of viruses that parasitize the microbes in cryoconite sediments. The researchers will use sediments previously collected from Antarctic glaciers that have varying concentrations of viruses and nutrients, to set up a nutrient-addition experiment to determine how nutrients affect microbial and viral population dynamics. The results will deepen our understanding of how microbial communities in general are shaped by nutrients and viruses and give new insights into the functioning of viruses in extremely cold environments. The researchers will publish their findings in scientific journals and will share their discoveries with K-12 students from rural schools in collaboration with the Pinhead Institute and will connect undergraduate students from under-represented minorities to polar research through participation in the universitys Science, Technology, Engineering \u0026 Mathematics Routes Uplift Research Program. Outreach will be achieved through videos produced and distributed by a professional science communicator. The research advances a National Science Foundation goal of expanding fundamental knowledge of Antarctic systems, biota, and processes by utilizing the unique characteristics of the Antarctic region as a science observing platform. \r\n\r\nThe Principal Investigators propose an experimental approach to understand how nutrient limitation affects microbial diversity and abundances and their cascading effects on virus diversity, abundance, and mode of infection (lysis vs. lysogeny) in Antarctic cryoconite holes. Cryoconite holes are ideal natural microcosms for manipulative studies, not available in other cryospheric ecosystems. The PIs will use previously collected cryoconite from across a gradient of both viral diversity and nutrient levels to address questions about key limiting nutrients and microbial-viral community dynamics in cryoconite sediments. Nutrient manipulation experiments will be conducted in a growth chamber that closely approximates the light and temperature regime of in situ cryoconite holes to test three core hypotheses: (1) phosphorus availability limits microbial productivity and abundance in cryoconite holes; (2) relaxing nutrient limitation in cryoconite from low-diversity glaciers will increase species diversity, leading microbial communities to resemble those found on more nutrient-rich glaciers; (3) relaxing nutrient limitation will increase the diversity and abundance of viruses by increasing the availability of suitable hosts, and decrease the prevalence of lysogenic infections. By manipulating nutrient limitation within a realistic range, this project will help verify hypothesized phosphorus limitation of Antarctic cryoconite holes and will extend understanding of the connections between nutrients, diversity, and viral infection dynamics in the cryosphere more generally. A better understanding of these dynamics in cryoconite sediments improves the ability of scientists to forecast future impacts of environmental changes in the cryosphere.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "AQUATIC ECOSYSTEMS; Taylor Valley", "locations": "Taylor Valley", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Varsani, Arvind; Porazinska, Dorota; Schmidt, Steven; Bergstrom, Anna", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Role of Nutrient Limitation and Viral Interactions on Antarctic Microbial Community Assembly: A Cryoconite Microcosm Study", "uid": "p0010418", "west": null}, {"awards": "1842542 Morgan, Daniel", "bounds_geometry": "POLYGON((160 -77,160.4 -77,160.8 -77,161.2 -77,161.6 -77,162 -77,162.4 -77,162.8 -77,163.2 -77,163.6 -77,164 -77,164 -77.1,164 -77.2,164 -77.3,164 -77.4,164 -77.5,164 -77.6,164 -77.7,164 -77.8,164 -77.9,164 -78,163.6 -78,163.2 -78,162.8 -78,162.4 -78,162 -78,161.6 -78,161.2 -78,160.8 -78,160.4 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 09 Aug 2022 00:00:00 GMT", "description": "The goal of this study is to identify and distinguish different source areas of glacial sediment in the McMurdo Dry Valleys, Antarctica to determine past glacial flow direction. Understanding ice flow is critical for determining how the Antarctic Ice Sheets have behaved in the past. Such insight is fundamental for allowing scientists to predict how the Antarctic Ice Sheets will evolve and, in turn, forecast how much and how fast sea level may rise. The project study site, the McMurdo Dry Valleys, contain a tremendous record of glacial deposits on land that extends back at least 14 million years. Chemistry of the rocks within the glacial deposits hold clues to the sources of ice that deposited the material. The chemical analyses of the glacial deposits will allow mapping of the former extent of glaciations providing a better understand of ice flow history. The mapping of the largest ice sheet expansion of the past 14 million years in the McMurdo Dry Valleys is of broad interest to the global climate change community. Undergraduate students comprise the majority of the field teams and will be responsible for sample preparation and analysis in the laboratory. \u003cbr/\u003e\u003cbr/\u003eThis project utilizes new geochemical techniques to test hypotheses about the source, extent, and flow patterns of the glacier ice that deposited glacial tills in the McMurdo Dry Valleys, Antarctica (MDV). The MDV contain an unparalleled terrestrial archive of glacial deposits, which record multiple sources of ice that deposited them. These include the northeast flowing ice that overrode the Transantarctic Mountains, the eastward expansion of the East Antarctic Ice Sheet, the westward extension of the Ross Ice Shelf representing an expansion of the West Antarctic Ice Sheet, and the growth of local alpine glaciers. The glacial tills and drifts in the Antarctic are typically isolated in patches or disjointed outcrop patterns making it difficult to correlate tills and determine their source. This project will undertake a systematic study of the tills in the McMurdo Dry Valleys to determine their provenance with a variety of geochemical techniques including major and minor element analyses with X-ray fluorescence, heavy mineral composition, soil salt concentration, and determining the uranium-lead (U-Pb) ages of zircon sands contained in these tills. The primary tool will be the age distribution of the population of detrital zircon in a glacial drift because it reflects the source of the tills and provides a unique geochemical \"fingerprint\" used to distinguish source areas while correlating units across different sites. A deliverable from this project will be a community available library of zircon fingerprints for mapped glacial tills from archived samples at the Polar Rock Repository and the systematic collection of samples in the MDV.\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": 164.0, "geometry": "POINT(162 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIATION; Dry Valleys", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Morgan, Daniel", "platforms": null, "repositories": null, "science_programs": null, "south": -78.0, "title": "Unlocking the Glacial History of the McMurdo Dry Valleys, Antarctica by Fingerprinting Glacial Tills with Detrital Zircon U-Pb Age Populations", "uid": "p0010368", "west": 160.0}, {"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": "1543367 Shubin, Neil", "bounds_geometry": "POLYGON((158.3 -77.5,158.54000000000002 -77.5,158.78 -77.5,159.02 -77.5,159.26 -77.5,159.5 -77.5,159.74 -77.5,159.98 -77.5,160.22 -77.5,160.45999999999998 -77.5,160.7 -77.5,160.7 -77.605,160.7 -77.71,160.7 -77.815,160.7 -77.92,160.7 -78.025,160.7 -78.13,160.7 -78.235,160.7 -78.34,160.7 -78.445,160.7 -78.55,160.45999999999998 -78.55,160.22 -78.55,159.98 -78.55,159.74 -78.55,159.5 -78.55,159.26 -78.55,159.02 -78.55,158.78 -78.55,158.54000000000002 -78.55,158.3 -78.55,158.3 -78.445,158.3 -78.34,158.3 -78.235,158.3 -78.13,158.3 -78.025,158.3 -77.92,158.3 -77.815,158.3 -77.71,158.3 -77.605,158.3 -77.5))", "dataset_titles": "Vertebrate Fossils from the Aztec Siltstone (Mid-Late Devonian); Vertebrate Fossils from the Aztec Siltstone (Mid-Late Devonian) 2 (2018-2019)", "datasets": [{"dataset_uid": "601580", "doi": "10.15784/601580", "keywords": "Acanthodii; Antarctica; Chondrichthyes; Early Vertebrates; Osteolepiformes; Paleontology; Placodermi; Transantarctic Mountains; Vertebrate Evolution", "people": "Daeschler, Ted", "repository": "USAP-DC", "science_program": null, "title": "Vertebrate Fossils from the Aztec Siltstone (Mid-Late Devonian)", "url": "https://www.usap-dc.org/view/dataset/601580"}, {"dataset_uid": "601584", "doi": "10.15784/601584", "keywords": "Acanthodii; Antarctica; Chondrichthyes; Early Vertebrates; Osteolepiformes; Paleontology; Placodermi; Transantarctic Mountains; Vertebrate Evolution", "people": "Daeschler, Ted", "repository": "USAP-DC", "science_program": null, "title": "Vertebrate Fossils from the Aztec Siltstone (Mid-Late Devonian) 2 (2018-2019)", "url": "https://www.usap-dc.org/view/dataset/601584"}], "date_created": "Fri, 17 Jun 2022 00:00:00 GMT", "description": "This research will provide new insights into the relationships and history of sharks, fish and limbed animals. Understanding these relationships forms the backbone for both basic and applied science because fish often serve as models of human traits and diseases. Some of the main lines of evidence for these relationships come from fossils in rocks over 380 million years old that were originally deposited as ancient rivers and streams. Because rocks of this type and age are abundantly exposed along a number of the dry valleys and mountains of Antarctica, the investigation of these areas holds exceptional promise for discoveries that can have a broad impact. The fieldwork will involve geological mapping and assessment of the rocks with detailed reconnaissance for the fossils that they may hold. Fossil discoveries form the backbone for public communication of the methods and results of scientific research-- these studies will be used as vehicles for training of students at multiple levels as well as communication of science to the broader non-science citizen base.\u003cbr/\u003e\u003cbr/\u003eThe discovery, description, and analysis of Middle to Late Devonian (390-355 Million years ago) vertebrates and depositional environments provide important data on the emergence of novel anatomical structures, faunas, and habitats during a critical interval in the history of life and earth. Biological innovation during this time includes the early evolution of freshwater fish, the origins of major groups of vertebrates (e.g., sharks, lobe and ray-finned fish, tetrapods), and the expansion and elaboration of non-marine ecosystems. Accordingly, expanding our knowledge of vertebrate diversity during the Middle and Late Devonian will provide new evidence on the relationships of the major groups of vertebrates, the assembly of novelties that ultimately enabled tetrapods to invade land, the origin and early evolution of sharks and their relatives, and the assembly and expansion of non-marine ecosystems generally. The Aztec Siltstone of Antarctica Middle-Late Devonian; Givetian-Frasnian Stages) has exceptional potential to produce new paleontological evidence of these events and to illuminate the temporal, ecological, and geographic context in which they occurred. It is essentially fossiliferous throughout its known exposure range, something that is rare for Middle-Late Devonian non-marine rocks anywhere in the world. In addition, fine-grained meandering stream deposits are abundantly exposed in the Aztec Siltstone and are recognized as an important locus for the discovery of well-preserved Devonian fish, including stem tetrapods and their relatives. Given the exceedingly fossiliferous nature of the Aztec Siltstone, the large number of taxa known only from partial material, and the amount of promising exposure yet to be worked, a dedicated reconnaissance, collection, and research effort is designed to recover important new fossil material and embed it in a stratigraphic and sedimentological context. The first major objective of this study is the recovery, preparation, and description of Middle-Late Devonian fossil taxa. Ensuing investigation of the phylogenetic affinities, taphonomic occurrence, and stratigraphic position of fossil assemblages will allow both local and global comparisons of biotic diversity. These analyses will inform: 1) higher level phylogenetic hypotheses of jawed vertebrates, 2) biostratigraphic and biogeographic analysis of the distribution of the Middle-Late Devonian fish, and 3) paleobiological investigation of the elaboration of terrestrial and freshwater habitats. The broader impacts are derived from the utility of paleontology and Antarctic expeditionary science as educational tools with powerful narratives. Specific goals include affiliations with local urban secondary schools (using established relationships for broadening participation) and collegiate and graduate training. Wider dissemination of knowledge to the general public is a direct product of ongoing interactions with national and international media (print, television, internet).", "east": 160.7, "geometry": "POINT(159.5 -78.025)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; AMD; FIELD INVESTIGATION; Transantarctic Mountains; USA/NSF; MACROFOSSILS; Fossils; USAP-DC", "locations": "Transantarctic Mountains", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e DEVONIAN", "persons": "Shubin, Neil; Daeschler, Edward B", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.55, "title": "Middle-Late Devonian Vertebrates of Antarctica", "uid": "p0010340", "west": 158.3}, {"awards": "2045880 Sokol, Eric; 2046260 Salvatore, Mark", "bounds_geometry": "POLYGON((161.88 -77.47,162.075 -77.47,162.27 -77.47,162.465 -77.47,162.66 -77.47,162.855 -77.47,163.05 -77.47,163.245 -77.47,163.44 -77.47,163.635 -77.47,163.83 -77.47,163.83 -77.501,163.83 -77.532,163.83 -77.563,163.83 -77.594,163.83 -77.625,163.83 -77.656,163.83 -77.687,163.83 -77.718,163.83 -77.749,163.83 -77.78,163.635 -77.78,163.44 -77.78,163.245 -77.78,163.05 -77.78,162.855 -77.78,162.66 -77.78,162.465 -77.78,162.27 -77.78,162.075 -77.78,161.88 -77.78,161.88 -77.749,161.88 -77.718,161.88 -77.687,161.88 -77.656,161.88 -77.625,161.88 -77.594,161.88 -77.563,161.88 -77.532,161.88 -77.501,161.88 -77.47))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 21 Apr 2022 00:00:00 GMT", "description": "Part I: Non-technical description: \r\nWater is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a remote method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training in high-school curricular programming in Native American communities of the Southwest U.S. \r\nPart II: Technical description: \r\nTerrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data needed to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from Native American communities in the Southwestern U.S., where similar desert conditions exist.\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": 163.83, "geometry": "POINT(162.855 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "ACTIVE LAYER; Taylor Valley; USAP-DC; Amd/Us; AMD; MODELS; USA/NSF", "locations": "Taylor Valley", "north": -77.47, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -77.78, "title": "Collaborative Research: Moving Beyond the Margins: Modeling Water Availability and Habitable Terrestrial Ecosystems in the Polar Desert of the McMurdo Dry Valleys", "uid": "p0010316", "west": 161.88}, {"awards": "0342484 Harwood, David", "bounds_geometry": "POINT(167.083333 -77.888889)", "dataset_titles": "Particle-size measurements at 3-m intervals for AND-2A sediment core, McMurdo Sound", "datasets": [{"dataset_uid": "601451", "doi": "10.15784/601451", "keywords": "Andrill; Antarctica; Continental Shelf; Diamict; McMurdo Sound; Miocene; Paleoclimate; Particle Size", "people": "Passchier, Sandra; Candice, Falk", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Particle-size measurements at 3-m intervals for AND-2A sediment core, McMurdo Sound", "url": "https://www.usap-dc.org/view/dataset/601451"}], "date_created": "Fri, 04 Feb 2022 00:00:00 GMT", "description": "ANDRILL is a scientific drilling program to investigate Antarctica\u0027s role in global climate change over the last sixty million years. The approach integrates geophysical surveys, new drilling technology, multidisciplinary core analysis, and ice sheet modeling to address four scientific themes: (1) the history of Antarctica\u0027s climate and ice sheets; (2) the evolution of polar biota and ecosystems; (3) the timing and nature of major tectonic and volcanic episodes; and (4) the role of Antarctica in the Earth\u0027s ocean-climate system. \u003cbr/\u003e\u003cbr/\u003eThis award initiates what may become a long-term program with drilling of two previously inaccessible sediment records beneath the McMurdo Ice Shelf and in South McMurdo Sound. These stratigraphic records cover critical time periods in the development of Antarctica\u0027s major ice sheets. The McMurdo Ice Shelf site focuses on the Ross Ice Shelf, whose size is a sensitive indicator of global climate change. It has recently undergone major calving events, and there is evidence of a thousand-kilometer contraction since the last glacial maximum. As a generator of cold bottom water, the shelf may also play a key role in ocean circulation. The core obtained from this site will also offer insight into sub-ice shelf sedimentary, biologic, and oceanographic processes; the history of Ross Island volcanism; and the flexural response of the lithosphere to volcanic loading, which is important for geophysical and tectonic studies of the region.\u003cbr/\u003e\u003cbr/\u003eThe South McMurdo Sound site is located adjacent to the Dry Valleys, and focuses on the major ice sheet overlying East Antarctica. A debate persists regarding the stability of this ice sheet. Evidence from the Dry Valleys supports contradictory conclusions; a stable ice sheet for at least the last fifteen million years or an active ice sheet that cycled through expansions and contractions as recently as a few millions of years ago. Constraining this history is critical to deep-time models of global climate change. The sediment cores will be used to construct an overall glacial and interglacial history for the region; including documentation of sea-ice coverage, sea level, terrestrial vegetation, and melt-water discharge events. The core will also provide a general chronostratigraphic framework for regional seismic studies and help unravel the area\u0027s complex tectonic history.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this project include formal and informal education, new research infrastructure, various forms of collaboration, and improving society\u0027s understanding of global climate change. Education is supported at the postdoctoral, graduate, undergraduate, and K-12 levels. Teachers and curriculum specialists are integrated into the research program, and a range of video resources will be produced, including a science documentary for television release. New research infrastructure includes equipment for core analysis and ice sheet modeling, as well as development of a unique drilling system to penetrate ice shelves. Drill development and the overall project are co-supported by international collaboration with scientists and the National Antarctic programs of New Zealand, Germany, and Italy. The program also forges new collaborations between research and primarily undergraduate institutions within the United States. \u003cbr/\u003e\u003cbr/\u003eAs key factors in sea-level rise and oceanic and atmospheric circulation, Antarctica\u0027s ice sheets are important to society\u0027s understanding of global climate change. ANDRILL offers new data on marine and terrestrial temperatures, and changes our understanding of extreme climate events like the formation of polar ice caps. Such data are critical to developing accurate models of the Earth\u0027s climatic future.", "east": 167.083333, "geometry": "POINT(167.083333 -77.888889)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USAP-DC; FIELD SURVEYS; ICE SHEETS; USA/NSF; Amd/Us; PALEOCLIMATE RECONSTRUCTIONS; Ross Ice Shelf; SEDIMENTS", "locations": "Ross Ice Shelf", "north": -77.888889, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Harwood, David; Levy, Richard", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.888889, "title": "Collaborative Research: ANDRILL - - Investigating Antarcticas Role in Cenozoic Global Environmental Change", "uid": "p0010297", "west": 167.083333}, {"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": "2039419 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.3,161.2 -77.3,161.4 -77.3,161.6 -77.3,161.8 -77.3,162 -77.3,162.2 -77.3,162.4 -77.3,162.6 -77.3,162.8 -77.3,163 -77.3,163 -77.35,163 -77.4,163 -77.45,163 -77.5,163 -77.55,163 -77.6,163 -77.65,163 -77.7,163 -77.75,163 -77.8,162.8 -77.8,162.6 -77.8,162.4 -77.8,162.2 -77.8,162 -77.8,161.8 -77.8,161.6 -77.8,161.4 -77.8,161.2 -77.8,161 -77.8,161 -77.75,161 -77.7,161 -77.65,161 -77.6,161 -77.55,161 -77.5,161 -77.45,161 -77.4,161 -77.35,161 -77.3))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 16 Dec 2021 00:00:00 GMT", "description": "The McMurdo Dry Valleys are the largest ice-free region in Antarctica and home to a seasonally active hydrologic system, with streams and saline lakes. Streams are fed by summer meltwater from local glaciers and snowbanks. Therefore, streamflow is tied to summer climate conditions such as air temperatures, ground temperatures, winds, and incoming solar radiation. Based on 50 years of monitoring, summer stream activity has been observed to change, and it likely varied during the geologic past in response to regional climate change and fluctuating glaciers. Thus, deposits from these streams can address questions about past climate, meltwater, and lake level changes in this region. How did meltwater streamflow respond to past climate change? How did streamflow vary during periods of glacial advance and retreat? At what times did large lakes fill many of the valleys and what was their extent? The researchers plan to acquire a record of stream activity for the Dry Valleys that will span the three largest valleys and a time period of about 100,000 years. This record will come from a series of active and ancient alluvial fans that were deposited by streams as they flowed from valley sidewalls onto valley floors. The study will provide a long-term context with which to assess recent observed changes to stream activity and lake levels. The research will be led by two female mid-career investigators and contribute significantly to student research opportunities and education. The research will contribute to graduate and undergraduate education by including students in both field and laboratory research, as well as incorporating data and results into the classroom. The research will be disseminated to K-12 and non-scientific communities through outreach that includes professional development training for K-12 teachers in eastern Massachusetts, development of hands-on activities, visits to K-12 classrooms, and STEM education and literacy activities in North Carolina.\r\n\r\nThe PIs propose to constrain rates of fluvial deposition and periods of increased fluvial activity in the McMurdo Dry Valleys during the Holocene and late Pleistocene. During 50 years of hydrologic monitoring in the Dry Valleys, scientists have observed that streams exhibit significant response to summer conditions. Previous studies of glacial and lacustrine deposits indicate regional glacier advance in the Dry Valleys during recent interglacial periods and high lake levels during and after the Last Glacial Maximum (LGM), with potentially significant low and high stands during the Holocene. However, the geologic record of meltwater activity is poorly constrained. The PIs seek to develop the first spatially-extensive record of stream deposition in the Dry Valleys by analyzing and dating alluvial fans. Given that alluvial fans are deposited by summer meltwater streams in a relatively stable tectonic setting, this record will serve as a proxy of regional summer climate conditions. Meltwater streams are an important component of the regional hydrologic system, connecting glaciers to lakes and affecting ecosystems and soils. A record of fluvial deposition is key to understanding the relationship between past climate change and regional hydrology. The proposed research will include remote- and field-based mapping of alluvial fans, stream channels, and meltwater sources as well as modeling potential incoming solar radiation to the fans and moisture sources during the austral summer. In the field, the PIs will document stratigraphy, collect near-surface sediments from 25 fans across four valleys (Taylor, Pearse, Wright, and Victoria), and collect 2- to 3-m vertical cores of ice-cemented sediments from three alluvial fan complexes. The PIs will then conduct depositional dating of fluvial sands via optically stimulated luminescence, and analyze mineralogy and bulk major element chemistry with X-ray powder diffraction and X-ray fluorescence. From these analyses, the PIs propose to (1) determine the timing of local- to regional-scale periods of high fluvial deposition, (2) calculate depositional rates, and (3) constrain depositional environments and sediment provenance. Given that many of the alluvial fans occur below the hypothesized maximum extents of glacially-dammed lakes in Wright and Victoria valleys, detailed stratigraphy, sediment provenance, and OSL dating of these fans could shed light on ongoing debates regarding the timing and extent of LGM and post-LGM lakes. The work will support a postdoctoral researcher, a PhD student, and many undergraduate and master\u2019s students in cross-disciplinary research that spans stratigraphy, geochemistry, paleoclimatology and physics.", "east": 163.0, "geometry": "POINT(162 -77.55)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Amd/Us; SEDIMENTS; USA/NSF; AMD; Dry Valleys; USAP-DC", "locations": "Dry Valleys", "north": -77.3, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -77.8, "title": "Collaborative Research: Holocene and Late Pleistocene Stream Deposition in the McMurdo Dry Valleys, Antarctica as a Proxy for Glacial Meltwater and Paleoclimate", "uid": "p0010285", "west": 161.0}, {"awards": "1744785 Barrett, John", "bounds_geometry": "POLYGON((-180 -77.62,-145.683 -77.62,-111.366 -77.62,-77.049 -77.62,-42.732 -77.62,-8.415 -77.62,25.902 -77.62,60.219 -77.62,94.536 -77.62,128.853 -77.62,163.17 -77.62,163.17 -77.618,163.17 -77.616,163.17 -77.614,163.17 -77.612,163.17 -77.61,163.17 -77.608,163.17 -77.606,163.17 -77.604,163.17 -77.602,163.17 -77.6,128.853 -77.6,94.536 -77.6,60.219 -77.6,25.902 -77.6,-8.415 -77.6,-42.732 -77.6,-77.049 -77.6,-111.366 -77.6,-145.683 -77.6,180 -77.6,178.319 -77.6,176.638 -77.6,174.957 -77.6,173.276 -77.6,171.595 -77.6,169.914 -77.6,168.233 -77.6,166.552 -77.6,164.871 -77.6,163.19 -77.6,163.19 -77.602,163.19 -77.604,163.19 -77.606,163.19 -77.608,163.19 -77.61,163.19 -77.612,163.19 -77.614,163.19 -77.616,163.19 -77.618,163.19 -77.62,164.871 -77.62,166.552 -77.62,168.233 -77.62,169.914 -77.62,171.595 -77.62,173.276 -77.62,174.957 -77.62,176.638 -77.62,178.319 -77.62,-180 -77.62))", "dataset_titles": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica", "datasets": [{"dataset_uid": "200260", "doi": "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", "url": "https://doi.org/10.6073/pasta/9acbbde9abc1e013f8c9fd9c383327f4"}], "date_created": "Tue, 30 Nov 2021 00:00:00 GMT", "description": "This package contains data collected from microbial mat surveys (i.e., percent cover, ash-free dry mass (AFDM), and pigment concentrations \u2013 chlorophyll-a, scytonemin, and carotenoids) associated with satellite-derived Normalized Difference Vegetation Index (NDVI) values from the Lake Fryxell Basin of Taylor Valley, located in the McMurdo Dry Valleys of Antarctica. The purpose of this study was to quantitatively compare key microbial mat characteristics to NDVI. Data were collected at seven plot locations within the Canada Glacier Antarctic Specially Protected Area (ASPA) near Canada Stream, as well as alongside Green Creek and McKnight Creek. NDVI values were derived from a WorldView-2 multispectral satellite image taken of the Lake Fryxell Basin on January 19, 2018, while biological ground surveying and sampling were conducted during the 2nd and 4th weeks of January 2018. ", "east": 163.19, "geometry": "POINT(-16.82 -77.61)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; ECOSYSTEM FUNCTIONS; FIELD SURVEYS; USAP-DC; USA/NSF; Taylor Valley; Amd/Us", "locations": "Taylor Valley", "north": -77.6, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Barrett, John; Salvatore, Mark", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -77.62, "title": "Collaborative Research: Remote characterization of microbial mats in Taylor Valley, Antarctica through in situ sampling and spectral validation", "uid": "p0010281", "west": 163.17}, {"awards": "1644171 Blackburn, Terrence", "bounds_geometry": "POLYGON((162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.2 -77.5,163.4 -77.5,163.6 -77.5,163.8 -77.5,164 -77.5,164 -77.525,164 -77.55,164 -77.575,164 -77.6,164 -77.625,164 -77.65,164 -77.675,164 -77.7,164 -77.725,164 -77.75,163.8 -77.75,163.6 -77.75,163.4 -77.75,163.2 -77.75,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,162 -77.725,162 -77.7,162 -77.675,162 -77.65,162 -77.625,162 -77.6,162 -77.575,162 -77.55,162 -77.525,162 -77.5))", "dataset_titles": "Isotopic ratios for subglacial precipitates from East Antarctica; U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "200240", "doi": "10.26022/IEDA/111548 ", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Isotopic ratios for subglacial precipitates from East Antarctica", "url": "https://doi.org/10.26022/IEDA/111548"}, {"dataset_uid": "601806", "doi": "10.15784/601806", "keywords": "Antarctica; Cryosphere; Erosion; Isotope Data; Major Elements; Soil; Taylor Glacier; Taylor Valley", "people": "Edwards, Graham; Piccione, Gavin; Blackburn, Terrence; Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601806"}], "date_created": "Fri, 13 Aug 2021 00:00:00 GMT", "description": "The primary scientific goal of the proposed project is to test whether Taylor Valley, Antarctica has experienced glacial incision in the last ~1 million years in spite of cold climate conditions. One of the Dry Valleys of the Transantarctic Mountains, Taylor Valley exhibits over 2000 m of relief from sub sea-level troughs to high polar peaks. The Dry Valleys are characterized by low mean annual temperatures, paucity of precipitation and erosion that has allowed fragile glacial landforms, now subaerially exposed at high elevations, to be preserved for as long as 15 Ma. Two end member models can explain the timing of glacial incision and the observation that Quaternary advances of Taylor Glacier have left deposits at lower valley elevations with each advance. In the first scenario, all Valley relief is generated prior to 15 Ma when non-polar climates enabled warm-based glaciers to incise and widen fluvial channels more so than peaks. In this case, Quaternary drift deposits record advances of cold-based glaciers of decreasing ice volume. Limited glacial erosion and silt generation results in drift deposits composed primarily of recycled sediments. In the second scenario, selective erosion of the valley floor continues to deepen Taylor Valley over the last 2 Ma while high elevation peaks remain uneroded in polar conditions. The \u2018bathtub rings\u2019 of Quaternary drifts reaching a progressively lower elevation through time could be due to the lowering of the valley floor by subglacial erosion and with it, production of silt which is now incorporated into these drifts. While either scenario would result in the present day topography, they differ in the implied evolution of regional glacial ice volume over time and the timing of both valley relief production and generation of fine-grained particles. Here we propose to distinguish between these two models, by placing time constrains on fine particle production using U-series comminution dating. This new geochronologic tool exploits the loss of 234U due to alpha-recoil. The deficiency in 234U only becomes detectable in particles with a sufficiently high surface-area-to-volume ratio which can incur appreciable 234U loss (\u003c50 \uf0ecm). The timing of comminution and particle size controls the magnitude of 234U loss, up to 10% in silt-sized particles comminuted over 1.5 million years ago. And while this geochronologic tool is in its infancy, the scientific goal of this proposal can be achieved by resolving between ancient and recently comminuted fine particles, a binary question that our preliminary modeling and measured data show is readily resolved.", "east": 164.0, "geometry": "POINT(163 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Taylor Valley", "locations": "Taylor Valley", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Blackburn, Terrence; Tulaczyk, Slawek", "platforms": null, "repo": "EarthChem", "repositories": "EarthChem; USAP-DC", "science_programs": null, "south": -77.75, "title": "U-Series Comminution Age Constraints on Taylor Valley Erosion", "uid": "p0010243", "west": 162.0}, {"awards": "1745080 Gillikin, David; 1745057 Walker, Sally; 1745064 Perez-Huerta, Alberto", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Analysis of striae groups and interstrial increments from Adamussium colbecki valves from Explorers Cove and Bay of Sails; Annual growth of Adamussium colbecki from Explorers Cove and Bay of Sails; Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores; Nitrogen, carbon, and oxygen isotopes in the shell of the Antarctic scallop Adamussium colbecki as a proxy for sea ice cover in Antarctica.; Stable isotopes of Oxygen and Carbon in Adamissium colbecki from Explorers Cove and Bay of Sails", "datasets": [{"dataset_uid": "600077", "doi": "10.15784/600077", "keywords": "Antarctica; Biota; Glaciers/ice Sheet; Glaciers/Ice Sheet; McMurdo Sound; Oceans; Sample/collection Description; Sample/Collection Description", "people": "Walker, Sally", "repository": "USAP-DC", "science_program": null, "title": "Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores", "url": "https://www.usap-dc.org/view/dataset/600077"}, {"dataset_uid": "601468", "doi": "10.15784/601468", "keywords": "Adamussium Colbecki; Antarctica; Growth; McMurdo Sound; Shell Fish", "people": "Walker, Sally; Cronin, Kelly", "repository": "USAP-DC", "science_program": null, "title": "Annual growth of Adamussium colbecki from Explorers Cove and Bay of Sails", "url": "https://www.usap-dc.org/view/dataset/601468"}, {"dataset_uid": "601764", "doi": null, "keywords": "Adamussium Colbecki; Antarctica; Biota; Carbon Isotopes; Explorers Cove; Nitrogen Isotopes; Oxygen Isotope; Scallop", "people": "Camarra, Steve; Gillikin, David; Verheyden, Anouk; Walker, Sally; Cronin, Kelly; Puhalski, Emma", "repository": "USAP-DC", "science_program": null, "title": "Nitrogen, carbon, and oxygen isotopes in the shell of the Antarctic scallop Adamussium colbecki as a proxy for sea ice cover in Antarctica.", "url": "https://www.usap-dc.org/view/dataset/601764"}, {"dataset_uid": "601761", "doi": "10.15784/601761", "keywords": "Adamussium Colbecki; Antarctica; Bay Of Sails; Carbon; Explorers Cove; McMurdo Sound; Oxygen; Stable Isotopes", "people": "Verheyden, Anouk; Bowser, Samuel S.; Perez-Huerta, Alberto; Andrus, Fred; Camarra, Steve; Puhalski, Emma; Gillikin, David; Cronin, Kelly; Walker, Sally", "repository": "USAP-DC", "science_program": null, "title": "Stable isotopes of Oxygen and Carbon in Adamissium colbecki from Explorers Cove and Bay of Sails", "url": "https://www.usap-dc.org/view/dataset/601761"}, {"dataset_uid": "601469", "doi": "10.15784/601469", "keywords": "Adamussium Colbecki; Antarctica; McMurdo", "people": "Walker, Sally; Cronin, Kelly", "repository": "USAP-DC", "science_program": null, "title": "Analysis of striae groups and interstrial increments from Adamussium colbecki valves from Explorers Cove and Bay of Sails", "url": "https://www.usap-dc.org/view/dataset/601469"}], "date_created": "Fri, 06 Aug 2021 00:00:00 GMT", "description": "The goal of this project is to discover whether the Antarctic scallop, Adamussium colbecki, provides a guide to sea-ice conditions in nearshore Antarctica today and in the past. Scallops may grow slower and live longer in habitats where sea ice persists for many years, limited by food, compared to habitats where sea ice melts out annually. Also, the chemicals retained in the shell during growth may provide crucial habitat information related to not only changing sea-ice conditions but also the type of food, whether it is recycled from the seafloor or produced by algae blooming when sea ice has melted. Unlocking the ecological imprint captured within the shell of the Antarctic Scallop will increase our understanding of changing sea-ice conditions in Antarctica. Further, because the Antarctic scallop had relatives living at the time when the Antarctic ice sheet first appeared, the scallop shell record may contain information on the stability of the ice sheet and the history of Antarctic shallow seas. Funding will also be integral for training a new generation of geoscientists in fossil and chemical forensics related to shallow sea habitats in Antarctica.\r\n\r\nScallops are worldwide in distribution, are integral for structuring marine communities have an extensive fossil record dating to the late Devonian, and are increasingly recognized as important paleoenvironmental proxies because they are generally well preserved in the sediment and rock record. The primary goal of this project is to assess the differences in growth, lifespan, and chemistry (stable isotopes, trace elements) archived in the shell of the Antarctic scallop that may be indicative of two ice states: persistent (multiannual) sea ice at Explorers Cove (EC) and annual sea ice (that melts out every year) at Bay of Sails (BOS), western McMurdo Sound, Antarctica. This project will investigate growth and lifespan proxies (physical and geochemical) and will use high-resolution records of stable oxygen isotopes to determine if a melt-water signal is archived in A. colbecki shells and whether that signal captures the differing ice behavior at two sites (EC versus BOS). Stable isotopes of carbon and nitrogen in association with trace elements will be used to examine subannual productivity spikes indicative of phytoplankton blooms, which are predicted to be more pronounced during open ocean conditions. Small growth increments in the outer calcite layer will be assessed to determine if they represent fortnightly growth, if so, they could provide a high-resolution proxy for monthly environmental processes. Unlocking the environmental archive preserved in A. colbecki shells may prove to be an important proxy for understanding changing sea-ice conditions in Antarctica\u0027s past. Funding will support a Ph.D. student and undergraduates from multiple institutions working on independent research projects. Web content focused on Antarctic marine communities will be designed for museum outreach, reaching thousands of middle-school children each year.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; PALEOCLIMATE RECONSTRUCTIONS; AMD; Dry Valleys; USAP-DC; LABORATORY; USA/NSF", "locations": "Dry Valleys", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Walker, Sally; Gillikin, David; Perez-Huerta, Alberto; Andrus, Fred", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past", "uid": "p0010238", "west": -180.0}, {"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": null, "keywords": "Antarctica; Cryosphere; Dry Valleys; Lake Fryxell; Laminae; Microbial Mat; Thickness", "people": "Paul, Ann; Sumner, Dawn; Juarez Rivera, Marisol; Mackey, Tyler; Hawes, Ian", "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": "1543344 Soreghan, Gerilyn", "bounds_geometry": null, "dataset_titles": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "datasets": [{"dataset_uid": "601599", "doi": "10.15784/601599", "keywords": "Antarctica; Anza Borrego; Iceland; McMurdo Dry Valleys; Norway; Peru; Puerto Rico; Taylor Valley; Washington; Wright Valley", "people": "Demirel-Floyd, Cansu", "repository": "USAP-DC", "science_program": null, "title": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "url": "https://www.usap-dc.org/view/dataset/601599"}], "date_created": "Tue, 18 May 2021 00:00:00 GMT", "description": "As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high \"weatherability\" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth\u0027s carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential \"weather ability\" and investigate how sediment produced in these glacial systems could ultimately impact Earth\u0027s carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.\r\n\r\nPhysical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; FIELD INVESTIGATION; USA/NSF; Dry Valleys; SEDIMENT CHEMISTRY; Amd/Us; Antarctica; Weathering", "locations": "Antarctica; Dry Valleys", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soreghan, Gerilyn; Elwood Madden, Megan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems", "uid": "p0010181", "west": null}, {"awards": "0838968 Putkonen, Jaakko; 0838757 Balco, Gregory", "bounds_geometry": "POLYGON((-158.00085 -83.2093,-157.945063 -83.2093,-157.889276 -83.2093,-157.833489 -83.2093,-157.777702 -83.2093,-157.721915 -83.2093,-157.666128 -83.2093,-157.610341 -83.2093,-157.554554 -83.2093,-157.498767 -83.2093,-157.44298 -83.2093,-157.44298 -83.50197,-157.44298 -83.79464,-157.44298 -84.08731,-157.44298 -84.37998,-157.44298 -84.67265,-157.44298 -84.96532,-157.44298 -85.25799,-157.44298 -85.55066,-157.44298 -85.84333,-157.44298 -86.136,-157.498767 -86.136,-157.554554 -86.136,-157.610341 -86.136,-157.666128 -86.136,-157.721915 -86.136,-157.777702 -86.136,-157.833489 -86.136,-157.889276 -86.136,-157.945063 -86.136,-158.00085 -86.136,-158.00085 -85.84333,-158.00085 -85.55066,-158.00085 -85.25799,-158.00085 -84.96532,-158.00085 -84.67265,-158.00085 -84.37998,-158.00085 -84.08731,-158.00085 -83.79464,-158.00085 -83.50197,-158.00085 -83.2093))", "dataset_titles": "Interface to observational data and geologic age information calculated therefrom; Web page with links to files containing cosmogenic noble gas concentrations and related analytical data", "datasets": [{"dataset_uid": "200197", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Interface to observational data and geologic age information calculated therefrom", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200198", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Web page with links to files containing cosmogenic noble gas concentrations and related analytical data", "url": "http://noblegas.berkeley.edu/~balcs/ongvalley/"}], "date_created": "Sun, 20 Dec 2020 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposed project will investigate the coldest and driest parts of the Transantarctic Mountains (Ong Valley at Nimrod Glacier and Moraine Canyon at Amundsen Glacier) where the lack of running water and biological activity in the modern environment is thought to have preserved the landscape, essentially unchanged, for millions of years. Contrary to this common belief, it is hypothesized that the landscape does evolve, perhaps as fast as many surfaces in the Dry Valleys area where both loose soil and bedrock surfaces have been degrading at a rate of about 1-2 m/Myrs for the past several million years. The research team will rely on analysis of the both stable and radioactive cosmogenic isotopes that accumulate in near surface soil and bedrock. Collectively these measurements allow comparison of the long term landscape evolution to current processes and environmental drivers such as wind speed. The results of this work will improve understanding of the evolution of the Earth\u0027s surface and directly aid in evaluating imagery of Martian geomorphology. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.", "east": -157.44298, "geometry": "POINT(-157.721915 -84.67265)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; NOT APPLICABLE; Antarctica", "locations": "Antarctica", "north": -83.2093, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Balco, Gregory; Putkonen, Jaakko; Morgan, Daniel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; PI website", "science_programs": null, "south": -86.136, "title": "Collaborative Research: Systematic Analysis of Landscape Evolution and Surface Ages in Transantarctic Mountains", "uid": "p0010152", "west": -158.00085}, {"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 Integrated System Science; Antarctic Earth Sciences", "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": "1620976 Johnson, Sarah", "bounds_geometry": "POLYGON((160 -77,160.3 -77,160.6 -77,160.9 -77,161.2 -77,161.5 -77,161.8 -77,162.1 -77,162.4 -77,162.7 -77,163 -77,163 -77.1,163 -77.2,163 -77.3,163 -77.4,163 -77.5,163 -77.6,163 -77.7,163 -77.8,163 -77.9,163 -78,162.7 -78,162.4 -78,162.1 -78,161.8 -78,161.5 -78,161.2 -78,160.9 -78,160.6 -78,160.3 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": "GenBank Sequence Read Archive with accession numbers SRR8217969 - SRR8217976 and project accession PRJNA506221", "datasets": [{"dataset_uid": "200164", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "GenBank Sequence Read Archive with accession numbers SRR8217969 - SRR8217976 and project accession PRJNA506221", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA506221/"}], "date_created": "Tue, 01 Sep 2020 00:00:00 GMT", "description": "Despite recent advances, we still know little about how life and its traces persist in extremely harsh conditions. What survival strategies do cells employ when pushed to their limit? Using a new technique, this project will investigate whether Antarctic paleolakes harbor \"microbial seed banks,\" or caches of viable microbes adapted to past paleoenvironments that could help transform our understanding of how cells survive over ancient timescales. Findings from this investigation could also illuminate novel DNA repair pathways with possible biomedical and biotechnology applications and help to refine life detection strategies for Mars. The project will bring Antarctic research to Georgetown University\u0027\u0027s campus for the first time, providing training opportunities in cutting edge analytical techniques for multiple students and a postdoctoral fellow. The field site will be the McMurdo Dry Valleys, which provide an unrivaled opportunity to investigate fundamental questions about the persistence of microbial life. Multiple lines of evidence, from interbedded and overlying ashfall deposits to parameterized models, suggest that the large-scale landforms there have remained essentially fixed as far back as the middle of the Miocene Epoch (i.e., ~8 million years ago). This geologic stability, coupled with geographic isolation and a steady polar climate, mean that biological activity has probably undergone few qualitative changes over the last one to two million years. The team will sample paleolake facies using sterile techniques from multiple Dry Valleys sites and extract DNA from entombed organic material. Genetic material will then be sequenced using Pacific Biosciences\u0027\u0027 Single Molecule, Real-Time DNA sequencing technology, which sequences native DNA as opposed to amplified DNA, thereby eliminating PCR primer bias, and enables read lengths that have never before been possible. The data will be analyzed with a range of bioinformatic techniques, with results that stand to impact our understanding of cell biology, Antarctic paleobiology, microbiology and biogeography, biotechnology, and planetary science.", "east": 163.0, "geometry": "POINT(161.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; COMMUNITY DYNAMICS; BACTERIA/ARCHAEA; CYANOBACTERIA (BLUE-GREEN ALGAE); LABORATORY; Dry Valleys", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Earth Sciences", "paleo_time": null, "persons": "Johnson, Sarah", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": -78.0, "title": "EAGER: Single-Molecule DNA Sequencing of Antarctic Paleolakes", "uid": "p0010125", "west": 160.0}, {"awards": "1935755 Lamp, Jennifer; 1935907 Balco, Gregory; 1935945 Tremblay, Marissa", "bounds_geometry": "POLYGON((160 -77.25,160.4 -77.25,160.8 -77.25,161.2 -77.25,161.6 -77.25,162 -77.25,162.4 -77.25,162.8 -77.25,163.2 -77.25,163.6 -77.25,164 -77.25,164 -77.325,164 -77.4,164 -77.475,164 -77.55,164 -77.625,164 -77.7,164 -77.775,164 -77.85,164 -77.925,164 -78,163.6 -78,163.2 -78,162.8 -78,162.4 -78,162 -78,161.6 -78,161.2 -78,160.8 -78,160.4 -78,160 -78,160 -77.925,160 -77.85,160 -77.775,160 -77.7,160 -77.625,160 -77.55,160 -77.475,160 -77.4,160 -77.325,160 -77.25))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 25 Aug 2020 00:00:00 GMT", "description": "Part I: Nontechnical\r\nScientists study the Earth\u0027s past climate in order to understand how the climate will respond to ongoing global change in the future. One of the best analogs for future climate might the period that occurred approximately 3 million years ago, during an interval known as the mid-Pliocene Warm Period. During this period, the concentration of carbon dioxide in the atmosphere was similar to today\u0027s and sea level was 15 or more meters higher, due primarily to warming and consequent ice sheet melting in polar regions. However, the temperatures in polar regions during the mid-Pliocene Warm Period are not well determined, in part because we do not have records like ice cores that extend this far back in time. This project will provide constraints on surface temperatures in Antarctica during the mid-Pliocene Warm Period using a new type of climate proxy, known as cosmogenic noble gas paleothermometry. This project focuses on an area of Antarctica called the McMurdo Dry Valleys. In this area, climate models suggest that temperatures were more than 10 \u00baC warmer during the mid-Pliocene than they are today, but indirect geologic observations suggest that temperatures may have been similar to today. The McMurdo Dry Valleys are also a place where rocks have been exposed to Earth surface conditions for several million years, and where this new climate proxy can be readily applied. The team will reconstruct temperatures in the McMurdo Dry Valleys during the mid-Pliocene Warm Period in order to resolve the discrepancy between models and indirect geologic observations and provide much-needed constraints on the sensitivity of Antarctic ice sheets to warming temperatures. The temperature reconstructions generated in this project will have scientific impact in multiple disciplines, including climate science, glaciology, geomorphology, and planetary science. In addition, the project will (1) broaden the participation of underrepresented groups by supporting two early-career female principal investigators, (2) build STEM talent through the education and training of a graduate student, (3) enhance infrastructure for research via publication of a publicly-accessible, open-source code library, and (4) be broadly disseminated via social media, blog posts, publications, and conference presentations. \r\n\r\nPart II: Technical Description\r\nThe mid-Pliocene Warm Period (3\u20133.3 million years ago) is the most recent interval of the geologic past when atmospheric CO2 concentrations exceeded 400 ppm, and is widely considered an analog for how Earths climate system will respond to current global change. Climate models predict polar amplification the occurrence of larger changes in temperatures at high latitudes than the global average due to a radiative forcing both during the mid-Pliocene Warm Period and due to current climate warming. However, the predicted magnitude of polar amplification is highly uncertain in both cases. The magnitude of polar amplification has important implications for the sensitivity of ice sheets to warming and the contribution of ice sheet melting to sea level change. Proxy-based constraints on polar surface air temperatures during the mid-Pliocene Warm Period are sparse to non-existent. In Antarctica, there is only indirect evidence for the magnitude of warming during this time. This project will provide constraints on surface temperatures in the McMurdo Dry Valleys of Antarctica during the mid-Pliocene Warm Period using a newly developed technique called cosmogenic noble gas (CNG) paleothermometry. CNG paleothermometry utilizes the diffusive behavior of cosmogenic 3He in quartz to quantify the temperatures rocks experience while exposed to cosmic-ray particles within a few meters of the Earths surface. The very low erosion rates and subzero temperatures characterizing the McMurdo Dry Valleys make this region uniquely suited for the application of CNG paleothermometry for addressing the question: what temperatures characterized the McMurdo Dry Valleys during the mid-Pliocene Warm Period? To address this question, the team will collect bedrock samples at several locations in the McMurdo Dry Valleys where erosion rates are known to be low enough that cosmic ray exposure extends into the mid-Pliocene or earlier. They will pair cosmogenic 3He measurements, which will record the thermal histories of our samples, with measurements of cosmogenic 10Be, 26Al, and 21Ne, which record samples exposure and erosion histories. We will also make in situ measurements of rock and air temperatures at sample sites in order to quantify the effect of radiative heating and develop a statistical relationship between rock and air temperatures, as well as conduct diffusion experiments to quantify the kinetics of 3He diffusion specific to each sample. This suite of observations will be used to model permissible thermal histories and place constraints on temperatures during the mid-Pliocene Warm Period interval of cosmic-ray exposure.", "east": 164.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; AMD; LABORATORY; USA/NSF; Amd/Us; ISOTOPES; Dry Valleys; AIR TEMPERATURE RECONSTRUCTION; GEOCHEMISTRY; USAP-DC", "locations": "Dry Valleys", "north": -77.25, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Tremblay, Marissa; Granger, Darryl; Balco, Gregory; Lamp, Jennifer", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -78.0, "title": "Collaborative \r\nResearch: Reconstructing Temperatures during the Mid-Pliocene Warm \r\nPeriod in the McMurdo Dry Valleys with Cosmogenic Noble Gases", "uid": "p0010123", "west": 160.0}, {"awards": "1443371 Fountain, Andrew", "bounds_geometry": "POLYGON((160.2 -77.1,160.57 -77.1,160.94 -77.1,161.31 -77.1,161.68 -77.1,162.05 -77.1,162.42 -77.1,162.79 -77.1,163.16 -77.1,163.53 -77.1,163.9 -77.1,163.9 -77.196,163.9 -77.292,163.9 -77.388,163.9 -77.484,163.9 -77.58,163.9 -77.676,163.9 -77.772,163.9 -77.868,163.9 -77.964,163.9 -78.06,163.53 -78.06,163.16 -78.06,162.79 -78.06,162.42 -78.06,162.05 -78.06,161.68 -78.06,161.31 -78.06,160.94 -78.06,160.57 -78.06,160.2 -78.06,160.2 -77.964,160.2 -77.868,160.2 -77.772,160.2 -77.676,160.2 -77.58,160.2 -77.484,160.2 -77.388,160.2 -77.292,160.2 -77.196,160.2 -77.1))", "dataset_titles": "McMurdo Dry Valleys LTER: A digital archive of human activity in the McMurdo Dry Valleys, Antarctica from 1902 to present", "datasets": [{"dataset_uid": "200086", "doi": "10.6073/pasta/0725cbd31f2af4bca2c6ad145e38dd3a", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "McMurdo Dry Valleys LTER: A digital archive of human activity in the McMurdo Dry Valleys, Antarctica from 1902 to present", "url": "https://doi.org/10.6073/pasta/0725cbd31f2af4bca2c6ad145e38dd3a"}], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "Beginning with the discovery of a \"curious valley\" in 1903 by Captain Scott, the McMurdo Dry Valleys (MDV) in Antarctica have been impacted by humans, although there were only three brief visits prior to 1950. Since the late 1950\u0027s, human activity in the MDV has become commonplace in summer, putting pressure on the region\u0027s fragile ecosystems through camp construction and inhabitation, cross-valley transport on foot and via vehicles, and scientific research that involves sampling and deployment of instruments. Historical photographs, put alongside information from written documentation, offer an invaluable record of the changing patterns of human activity in the MDV. Photographic images often show the physical extent of field camps and research sites, the activities that were taking place, and the environmental protection measures that were being followed. Historical photographs of the MDV, however, are scattered in different places around the world, often in private collections, and there is a real danger that many of these photos may be lost, along with the information they contain. This project will collect and digitize historical photographs of sites of human activity in the MDV from archives and private collections in the United States, New Zealand, and organize them both chronologically and spatially in a GIS database. Sites of past human activities will be re-photographed to provide comparisons with the present, and re-photography will assist in providing spatial data for historical photographs without obvious location information. The results of this analysis will support effective environmental management into the future. The digital photo archive will be openly available through the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) website (www.mcmlter.org), where it can be used by scientists, environmental managers, and others interested in the region. \u003cbr/\u003e\u003cbr/\u003eThe central question of this project can be reformulated as a hypothesis: Despite an overall increase in human activities in the MDV, the spatial range of these activities has become more confined over time as a result of an increased awareness of ecosystem fragility and efforts to manage the region. To address this hypothesis, the project will define the spatial distribution and temporal frequency of human activity in the MDV. Photographs and reports will be collected from archives with polar collections such as the National Archives of New Zealand in Wellington and Christchurch and the Byrd Polar Research Center in Ohio. Private photograph collections will be accessed through personal connections, social media, advertisements in periodicals such as The Polar Times, and other means. Re-photography in the field will follow established techniques and will create benchmarks for future research projects. The spatial data will be stored in an ArcGIS database for analysis and quantification of the human footprint over time in the MDV. The improved understanding of changing patterns of human activity in the MDV provided by this historical photo archive will provide three major contributions: 1) a fundamentally important historic accounting of human activity to support current environmental management of the MDV; 2) defining the location and type of human activity will be of immediate benefit in two important ways: a) places to avoid for scientists interested in sampling pristine landscapes, and, b) targets of opportunity for scientists investigating the long-term environmental legacy of human activity; and 3) this research will make an innovative contribution to knowledge of the environmental history of the MDV.", "east": 163.9, "geometry": "POINT(162.05 -77.58)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "CONTAMINANT LEVELS/SPILLS; Antarctica; NOT APPLICABLE; USAP-DC", "locations": "Antarctica", "north": -77.1, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Fountain, Andrew; Howkins, Adrian", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -78.06, "title": "Collaborative Research: Assessing Changing Patterns of Human Activity in the McMurdo Dry Valleys using Digital Photo Archives", "uid": "p0010066", "west": 160.2}, {"awards": "1341680 Sletten, Ronald", "bounds_geometry": "POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": "Chemical and physical characterization of Beacon Valley and Victoria Valley permafrost cores", "datasets": [{"dataset_uid": "601247", "doi": "10.15784/601247", "keywords": "Aluminum-26; Antarctica; Be-10; Cosmogenic; Dry Valleys; Geochemistry; Permafrost", "people": "Sletten, Ronald S.", "repository": "USAP-DC", "science_program": null, "title": "Chemical and physical characterization of Beacon Valley and Victoria Valley permafrost cores", "url": "https://www.usap-dc.org/view/dataset/601247"}], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "Intellectual Merit: This project will yield new information on the long term Antarctic climate and landscape evolution from measurements of cosmogenic nuclides in quartz sand from two unique permafrost cores collected in Beacon Valley, Antarctica. The two cores have already been drilled in ice-cemented, sand-rich permafrost at 5.5 and 30.6 meters depth, and are currently in cold storage at the University of Washington. The cores are believed to record the monotonic accumulation of sand that has been blown into lower Beacon Valley and inflated the surface over time. The rate of accumulation and any hiatus in the accumulation are believed to reflect in part the advance and retreat of the Taylor Glacier. Preliminary measurements of cosmogenically-produced beryllium (10Be) and aluminum (26Al) in quartz sand in the 5.5-meter depth core reveal that it has been accreting at a rate of 2.5 meters/Myr for the past million years. Furthermore, prior to that time, lower Beacon Valley was most likely covered (shielded from the atmosphere thereby having no or very low production of cosmogenic nuclides in quartz) by Taylor Glacier from 1 to 3.5 Myr BP. These preliminary measurements also suggest that the 30.6 meter core may provide a record of over 10 million years. The emphasis is the full characterization of the core and analysis of cosmogenic nuclides (including cosmogenic neon) in the 30.6 meter permafrost core to develop a burial history of the sands and potentially a record the waxing and waning of the Taylor Glacier. This will allow new tests of our current understanding of surface dynamics and climate history in the McMurdo Dry Valleys (MDV) based on the dated stratigraphy of eolian sand that has been accumulating and inflating the surface for millions of years. This is a new process of surface inflation whose extent has not been well documented, and holds the potential to develop a continuous history of surface burial and glacial expansion. This project will provide a new proxy for understanding the climatic history of the Dry Valleys and will test models for the evolution of permafrost in Beacon Valley.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003e\u003cbr/\u003eThe landscape history of the McMurdo Dry Valleys is important because geological deposits there comprise the richest terrestrial record available from Antarctica. By testing the current age model for these deposits, we will improve understanding of Antarctica?s role in global climate change. This project will train one graduate and one undergraduate student in geochemistry, geochronology, and glacial and periglacial geology. They will participate substantively in the research and are expected to develop their own original ideas. Results from this work will be incorporated into undergraduate and graduate teaching curricula, will be published in the peer reviewed literature, and the data will be made public.", "east": 162.0, "geometry": "POINT(161 -77.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE; BOREHOLES; Antarctica", "locations": "Antarctica", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Sletten, Ronald S.; Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Ancient landscape-active Surfaces: Periglacial Hyperinflation in soils of Beacon Valley, Antarctica", "uid": "p0010068", "west": 160.0}, {"awards": "1643550 Sletten, Ronald", "bounds_geometry": "POLYGON((160.5 -77.3,160.67 -77.3,160.84 -77.3,161.01 -77.3,161.18 -77.3,161.35 -77.3,161.52 -77.3,161.69 -77.3,161.86 -77.3,162.03 -77.3,162.2 -77.3,162.2 -77.35,162.2 -77.4,162.2 -77.45,162.2 -77.5,162.2 -77.55,162.2 -77.6,162.2 -77.65,162.2 -77.7,162.2 -77.75,162.2 -77.8,162.03 -77.8,161.86 -77.8,161.69 -77.8,161.52 -77.8,161.35 -77.8,161.18 -77.8,161.01 -77.8,160.84 -77.8,160.67 -77.8,160.5 -77.8,160.5 -77.75,160.5 -77.7,160.5 -77.65,160.5 -77.6,160.5 -77.55,160.5 -77.5,160.5 -77.45,160.5 -77.4,160.5 -77.35,160.5 -77.3))", "dataset_titles": "Timelapse photography of Don Juan Pond and surrounding basin", "datasets": [{"dataset_uid": "601487", "doi": "10.15784/601487", "keywords": "Antarctica; Brine; CaCl2; Don Juan Pond; Dry Valleys; Salt", "people": "Toner, Jonathan; Sletten, Ronald S.; Mushkin, Amit", "repository": "USAP-DC", "science_program": null, "title": "Timelapse photography of Don Juan Pond and surrounding basin", "url": "https://www.usap-dc.org/view/dataset/601487"}], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "This study aims to better understand salt accumulation in cold deserts and develop a model of salt transport by groundwater. Cold deserts, like the Antarctic McMurdo Dry Valleys (MDV), are similar to hot deserts in that they accumulate high concentrations of salts because there is not enough water to flush the salts out of the soils into the ocean. The accumulation of salt allows for the creation of brine-rich groundwater that freezes at much lower temperatures. Field work will focus on several groundwater features in the MDV including Don Juan Pond, a shallow lake that accumulates extremely high levels of salts and does not freeze until the temperature reaches -51 degrees C (-60 degrees F). The setting offers the potential to better understand this unique water environment including life at its extremes. It also serves as an analog environment for Mars, a planet that is entirely underlain by permafrost, similar to the MDV. This project will support a doctoral student at the University of Washington Department of Earth and Space Sciences, who will be trained in chemical analysis, chemical and physical modeling, and remote field work in a polar desert environment.\u003cbr/\u003e\u003cbr/\u003ePast research suggests that the movement of soluble ions in sediment and soil is controlled by the water activity, permeability, and the thermal regime; however, processes controlling the ionic redistribution in Antarctic environments are poorly constrained. This project aims to better understand the formation, salt redistribution, and water activity of pervasive brine-rich groundwater that is enriched in calcium chloride. A primary goal is to develop a brine thermal;reactive;transport model for the MDV region using data collected from the field to constrain model inputs and ground-truth model outputs. The model will develop a Pitzer-type thermodynamic, reactive transport model and couple it to a ground temperature model. The model will test mechanisms of groundwater formation in the MDV and the properties (e.g. composition, temperature, and water activity) of widespread shallow brine-rich waters. Water is an essential ingredient for life and defining processes that control the availability of water is critical for understanding the habitability of extreme environments, including Mars.", "east": 162.2, "geometry": "POINT(161.35 -77.55)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERA", "is_usap_dc": true, "keywords": "Amd/Us; AMD; Antarctica; USA/NSF; USAP-DC; SOIL CHEMISTRY; FIELD INVESTIGATION", "locations": "Antarctica", "north": -77.3, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sletten, Ronald S.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Formation and Characteristics of Brine-rich Water in the Dry Valleys, Antarctica", "uid": "p0010069", "west": 160.5}, {"awards": "1443578 Schmidt, Steven", "bounds_geometry": "POLYGON((161.5 -77.5,161.7 -77.5,161.9 -77.5,162.1 -77.5,162.3 -77.5,162.5 -77.5,162.7 -77.5,162.9 -77.5,163.1 -77.5,163.3 -77.5,163.5 -77.5,163.5 -77.53,163.5 -77.56,163.5 -77.59,163.5 -77.62,163.5 -77.65,163.5 -77.68,163.5 -77.71,163.5 -77.74,163.5 -77.77,163.5 -77.8,163.3 -77.8,163.1 -77.8,162.9 -77.8,162.7 -77.8,162.5 -77.8,162.3 -77.8,162.1 -77.8,161.9 -77.8,161.7 -77.8,161.5 -77.8,161.5 -77.77,161.5 -77.74,161.5 -77.71,161.5 -77.68,161.5 -77.65,161.5 -77.62,161.5 -77.59,161.5 -77.56,161.5 -77.53,161.5 -77.5))", "dataset_titles": "16S and 18S amplicon sequencing of Antarctic cryoconite holes; Genomes of Antarctic ssDNA viruses (GenBank accession numbers MN311489-MN311492 and MN328267-MN328291); Metadata from samples (in the process of submitting to EDI; will update with DOI once completed); Microbial species-area relationships in Antarctic cryoconite holes; Soil microbial communities of a mountain landscape, McMurdo Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "200084", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Genomes of Antarctic ssDNA viruses (GenBank accession numbers MN311489-MN311492 and MN328267-MN328291)", "url": ""}, {"dataset_uid": "200081", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "16S and 18S amplicon sequencing of Antarctic cryoconite holes", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA480849/"}, {"dataset_uid": "200281", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Microbial species-area relationships in Antarctic cryoconite holes", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA668398/"}, {"dataset_uid": "200279", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Metadata from samples (in the process of submitting to EDI; will update with DOI once completed)", "url": "https://github.com/pacificasommers/Cryoconite-metadata"}, {"dataset_uid": "200280", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Soil microbial communities of a mountain landscape, McMurdo Dry Valleys, Antarctica", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA721735/"}], "date_created": "Fri, 01 Nov 2019 00:00:00 GMT", "description": "Cryoconite holes are pockets of life completely encased in otherwise barren glacial ice. These pockets of life form when dust blown onto the ice melts a small, largely isolated hole that can function as its own tiny ecosystem. This dust can contain microorganisms such as bacteria, algae, or microscopic animals. The microorganisms within the hole interact and carry out functions typical of a larger ecosystem, such as a forest. Cryoconite holes are especially important in extreme cold environments such as the Antarctic Dry Valleys, where they function as repositories of life. Because cryoconite holes are mostly enclosed and persist for years, they can be tracked over time to test fundamental scientific questions about how communities of interacting organisms develop to become fully functioning ecosystems. This project will sample existing and experimentally created cryoconite holes to understand how these ecosystems develop and to what degree random processes (such as which organisms get there first) affect the final community composition and functioning. The results will not only improve our understanding of how microbial communities assemble and affect the functioning of microecosystems such as cryoconite holes, but also how the processes of community assembly affect functioning of larger ecosystems, such as forests. A better understanding of community establishment, development, and response to abiotic factors are essential to forecasting ecological responses to environmental change.\u003cbr/\u003e\u003cbr/\u003eIt is essential to unravel the links between community assembly, biodiversity, and nutrient cycling across numerous ecosystems because these are critical factors determining ecological responses to environmental change. The unique, largely isolated nature of cryoconite holes provides an experimental system that will advance fundamental understanding of the processes (e.g., stochastic dynamics such as dispersal limitation, assembly order, and ecological drift) driving community assembly. This project will use a field sampling campaign and a number of manipulative experiments to test a hypothesis that unites theory in community and ecosystem ecology: the degree to which stochastic processes guide microbial community assembly and affects regional patterns in biodiversity and ecosystem processes. Cryoconite holes will be sampled to compare community composition, environmental factors, and ecosystem functioning between hydrologically connected and isolated holes. New cryoconite holes will also be constructed and monitored over the course of two growing seasons to specifically alter assembly order and community size, thereby pairing a unique manipulative experiment with field surveys to address questions with relevance to the Antarctic and beyond. Amplicon sequencing, metagenomics, microscopy, sensitive environmental chemistry methods, and photosynthesis and respiration measurements will be used to test a series of sub-hypotheses that relate stochasticity to patterns in regional biodiversity, heterogeneity in environmental factors, and ecosystem processes.", "east": 163.5, "geometry": "POINT(162.5 -77.65)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "GLACIERS; Antarctica; USAP-DC; FIELD INVESTIGATION", "locations": "Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Schmidt, Steven; Cawley, Kaelin; Fountain, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "NCBI GenBank", "repositories": "GitHub; NCBI GenBank", "science_programs": null, "south": -77.8, "title": "Collaborative Research: Stochasticity and Cryoconite Community Assembly and Function", "uid": "p0010063", "west": 161.5}, {"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": "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": "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"}, {"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"}], "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": "EDI", "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": "1544526 Omelon, Christopher", "bounds_geometry": "POLYGON((160 -76.5,160.37 -76.5,160.74 -76.5,161.11 -76.5,161.48 -76.5,161.85 -76.5,162.22 -76.5,162.59 -76.5,162.96 -76.5,163.33 -76.5,163.7 -76.5,163.7 -76.63,163.7 -76.76,163.7 -76.89,163.7 -77.02,163.7 -77.15,163.7 -77.28,163.7 -77.41,163.7 -77.54,163.7 -77.67,163.7 -77.8,163.33 -77.8,162.96 -77.8,162.59 -77.8,162.22 -77.8,161.85 -77.8,161.48 -77.8,161.11 -77.8,160.74 -77.8,160.37 -77.8,160 -77.8,160 -77.67,160 -77.54,160 -77.41,160 -77.28,160 -77.15,160 -77.02,160 -76.89,160 -76.76,160 -76.63,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 May 2019 00:00:00 GMT", "description": "Cryptoendoliths are organisms that colonize microscopic cavities of rocks, which give them protection and allow them to inhabit extreme environments, such as the cold, arid desert of the Dry Valleys of Antarctica. Fossilized cryptoendoliths preserve the forms and features of organisms from the past and thus provide a unique opportunity to study the organisms\u0027 life histories and environments. To study this fossil record, there needs to be a better understanding of what environmental conditions allow these fossils to form. A climate gradient currently exists in the Dry Valleys that allows us to study living, dead, and fossilized cryptoendoliths from mild to increasingly harsh environments; providing insight to the limits of life and how these fossils are formed. This project will develop instruments to detect the biological activity of the live microorganisms and conduct laboratory experiments to determine the environmental limits of their survival. The project also will characterize the chemical and structural features of the living, dead, and fossilized cryptoendoliths to understand how they become fossilized. Knowing how microorganisms are preserved as fossils in cold and dry environments like Antarctica can help to refine methods that can be used to search for and identify evidence for extraterrestrial life in similar habitats on planets such as Mars. This project includes training of graduate and undergraduate students.\r\n\r\nLittle is known about cryptoendolithic microfossils and their formation processes in cold, arid terrestrial habitats of the Dry Valleys of Antarctica, where a legacy of activity is discernible in the form of biosignatures including inorganic materials and microbial fossils that preserve and indicate traces of past biological activity. The overarching goals of the proposed work are: (1) to determine how rates of microbial respiration and biodegradation of organic matter control microbial fossilization; and (2) to characterize microbial fossils and their living counterparts to elucidate mechanisms for fossilization. Using samples collected across an increasingly harsher (more cold and dry) climatic gradient that encompasses living, dead, and fossilized cryptoendolithic microorganisms, the proposed work will: (1) develop an instrument to be used in the field that can measure small concentrations of CO2 in cryptoendolithic habitats in situ; (2) use microscopy techniques to characterize endolithic microorganisms as well as the chemical and morphological characteristics of biosignatures and microbial fossils. A metagenomic survey of microbial communities in these samples will be used to characterize differences in diversity, identify if specific microorganisms (e.g. prokaryotes, eukaryotes) are more capable of surviving under these harsh climatic conditions, and to corroborate microscopic observations of the viability states of these microorganisms.", "east": 163.7, "geometry": "POINT(161.85 -77.15)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; NOT APPLICABLE; TERRESTRIAL ECOSYSTEMS", "locations": "Antarctica", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Omelon, Christopher; Breecker, Daniel; Bennett, Philip", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -77.8, "title": "Activity, Preservation and Fossilization of Cryptoendolithic Microorganisms in Antarctica", "uid": "p0010028", "west": 160.0}, {"awards": "1144192 Tulaczyk, Slawek; 1144177 Pettit, Erin; 1144176 Lyons, W. Berry; 1727387 Mikucki, Jill", "bounds_geometry": "POLYGON((161.8 -77.7,161.88 -77.7,161.96 -77.7,162.04000000000002 -77.7,162.12 -77.7,162.2 -77.7,162.28 -77.7,162.36 -77.7,162.44 -77.7,162.51999999999998 -77.7,162.6 -77.7,162.6 -77.70700000000001,162.6 -77.714,162.6 -77.721,162.6 -77.728,162.6 -77.735,162.6 -77.742,162.6 -77.749,162.6 -77.756,162.6 -77.76299999999999,162.6 -77.77,162.51999999999998 -77.77,162.44 -77.77,162.36 -77.77,162.28 -77.77,162.2 -77.77,162.12 -77.77,162.04000000000002 -77.77,161.96 -77.77,161.88 -77.77,161.8 -77.77,161.8 -77.76299999999999,161.8 -77.756,161.8 -77.749,161.8 -77.742,161.8 -77.735,161.8 -77.728,161.8 -77.721,161.8 -77.714,161.8 -77.70700000000001,161.8 -77.7))", "dataset_titles": "Ablation Stake Data from of Taylor Glacier near Blood Falls; Antarctica Support 2014/2015 - C-528 Blood Falls GPS/GNSS Observations Dataset; Blood Falls, McMurdo Dry Va. International Federation of Digital Seismograph Networks. Dataset/Seismic Network; FLIR thermal imaging data near Blood Falls, Taylor Glacier; Ground Penetrating Radar Data near Blood Falls, Taylor Glacier; Ice Temperature in Shallow Boreholes Near Blood Falls at the Terminus of Taylor Glacier, McMurdo Dry Valleys, Antarctica; NCBI short read archive -Metagenomic survey of Antarctic Groundwater; Terrestrial Radar Interferometry near Blood Falls, Taylor Glacier; The Geochemistry of englacial brine from Taylor Glacier, Antarctica; Time Lapse imagery of the Blood Falls feature, Antarctica ; Vaisala Integrated Met Station near Blood Falls, Taylor Glacier", "datasets": [{"dataset_uid": "601164", "doi": "10.15784/601164", "keywords": "Antarctica; Basal Crevassing; Glacier Hydrology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Snow/ice; Snow/Ice", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": null, "title": "Ablation Stake Data from of Taylor Glacier near Blood Falls", "url": "https://www.usap-dc.org/view/dataset/601164"}, {"dataset_uid": "601165", "doi": "10.15784/601165", "keywords": "Antarctica; Basal Crevassing; Glacier Hydrology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Radar; Snow/ice; Snow/Ice; Taylor Glacier", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": null, "title": "Ground Penetrating Radar Data near Blood Falls, Taylor Glacier", "url": "https://www.usap-dc.org/view/dataset/601165"}, {"dataset_uid": "601139", "doi": "10.15784/601139", "keywords": "Antarctica; Borehole; Borehole Logging; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Temperature; Snow/ice; Snow/Ice; Temperature; Temperature Profiles", "people": "Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "Ice Temperature in Shallow Boreholes Near Blood Falls at the Terminus of Taylor Glacier, McMurdo Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601139"}, {"dataset_uid": "601166", "doi": "10.15784/601166", "keywords": "Antarctica; Basal Crevassing; Glacier Hydrology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Radar; Snow/ice; Snow/Ice; Taylor Glacier", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": null, "title": "Terrestrial Radar Interferometry near Blood Falls, Taylor Glacier", "url": "https://www.usap-dc.org/view/dataset/601166"}, {"dataset_uid": "601167", "doi": "10.15784/601167", "keywords": "Antarctica; Basal Crevassing; Glacier Hydrology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Photo; Photo/video; Photo/Video; Snow/ice; Snow/Ice; Taylor Glacier; Timelaps Images", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": null, "title": "Time Lapse imagery of the Blood Falls feature, Antarctica ", "url": "https://www.usap-dc.org/view/dataset/601167"}, {"dataset_uid": "601168", "doi": "10.15784/601168", "keywords": "Antarctica; Atmosphere; Basal Crevassing; Glacier Hydrology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Meteorology; Taylor Glacier; Temperature; Weather Station Data; Wind Speed", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": null, "title": "Vaisala Integrated Met Station near Blood Falls, Taylor Glacier", "url": "https://www.usap-dc.org/view/dataset/601168"}, {"dataset_uid": "601179", "doi": "10.15784/601179", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Brine", "people": "Gardner, Christopher B.; Lyons, W. Berry", "repository": "USAP-DC", "science_program": null, "title": "The Geochemistry of englacial brine from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601179"}, {"dataset_uid": "200028", "doi": "10.7283/FCEN-8050", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica Support 2014/2015 - C-528 Blood Falls GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/fcen-8050"}, {"dataset_uid": "601169", "doi": "10.15784/601169", "keywords": "Antarctica; Basal Crevassing; Glacier Hydrology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Infrared Imagery; Photo/video; Photo/Video; Taylor Glacier; Thermal Camera; Timelaps Images", "people": "Pettit, Erin", "repository": "USAP-DC", "science_program": null, "title": "FLIR thermal imaging data near Blood Falls, Taylor Glacier", "url": "https://www.usap-dc.org/view/dataset/601169"}, {"dataset_uid": "200074", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "NCBI short read archive -Metagenomic survey of Antarctic Groundwater", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRR6667787"}, {"dataset_uid": "200029", "doi": "10.7914/SN/YW_2013", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Blood Falls, McMurdo Dry Va. International Federation of Digital Seismograph Networks. Dataset/Seismic Network", "url": "http://www.fdsn.org/networks/detail/YW_2013/"}], "date_created": "Wed, 28 Nov 2018 00:00:00 GMT", "description": "Recent discoveries of widespread liquid water and microbial ecosystems below the Antarctic ice sheets have generated considerable interest in studying Antarctic subglacial environments. Understanding subglacial hydrology, the persistence of life in extended isolation and the evolution and stability of subglacial habitats requires an integrated, interdisciplinary approach. The collaborative project, Minimally Invasive Direct Glacial Exploration (MIDGE) of the Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys will integrate geophysical measurements, molecular microbial ecology and geochemical analyses to explore a unique Antarctic subglacial system known as Blood Falls. Blood Falls is a hypersaline, subglacial brine that supports an active microbial community. The subglacial brine is released from a crevasse at the surface of the Taylor Glacier providing an accessible portal into an Antarctic subglacial ecosystem. Recent geochemical and molecular analyses support a marine source for the salts and microorganisms in Blood Falls. The last time marine waters inundated this part of the McMurdo Dry Valleys was during the Late Tertiary, which suggests the brine is ancient. Still, no direct samples have been collected from the subglacial source to Blood Falls and little is known about the origin of this brine or the amount of time it has been sealed below Taylor Glacier. Radar profiles collected near Blood Falls delineate a possible fault in the subglacial substrate that may help explain the localized and episodic nature of brine release. However it remains unclear what triggers the episodic release of brine exclusively at the Blood Falls crevasse or the extent to which the brine is altered as it makes its way to the surface. \u003cbr/\u003e\u003cbr/\u003eThe MIDGE project aims to determine the mechanism of brine release at Blood Falls, evaluate changes in the geochemistry and the microbial community within the englacial conduit and assess if Blood Falls waters have a distinct impact on the thermal and stress state of Taylor Glacier, one of the most studied polar glaciers in Antarctica. The geophysical study of the glaciological structure and mechanism of brine release will use GPR, GPS, and a small passive seismic network. Together with international collaborators, the \u0027Ice Mole\u0027 team from FH Aachen University of Applied Sciences, Germany (funded by the German Aerospace Center, DLR), MIDGE will develop and deploy innovative, minimally invasive technologies for clean access and brine sample retrieval from deep within the Blood Falls drainage system. These technologies will allow for the collection of samples of the brine away from the surface (up to tens of meters) for geochemical analyses and microbial structure-function experiments. There is concern over the contamination of pristine subglacial environments from chemical and biological materials inherent in the drilling process; and MIDGE will provide data on the efficacy of thermoelectric probes for clean access and retrieval of representative subglacial samples. Antarctic subglacial environments provide an excellent opportunity for researching survivability and adaptability of microbial life and are potential terrestrial analogues for life habitats on icy planetary bodies. The MIDGE project offers a portable, versatile, clean alternative to hot water and mechanical drilling and will enable the exploration of subglacial hydrology and ecosystem function while making significant progress towards developing technologies for minimally invasive and clean sampling of icy systems.", "east": 162.6, "geometry": "POINT(162.2 -77.735)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; BACTERIA/ARCHAEA; USAP-DC", "locations": null, "north": -77.7, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Instrumentation and Support; Antarctic Integrated System Science", "paleo_time": null, "persons": "Tulaczyk, Slawek; Pettit, Erin; Lyons, W. Berry; Mikucki, Jill", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "IRIS; NCBI GenBank; UNAVCO; USAP-DC", "science_programs": null, "south": -77.77, "title": "Collaborative Research: MIDGE: Minimally Invasive Direct Glacial Exploration of Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys", "uid": "p0000002", "west": 161.8}, {"awards": "1246292 Cary, Stephen", "bounds_geometry": "POLYGON((161.36062 -77.20215,161.610171 -77.20215,161.859722 -77.20215,162.109273 -77.20215,162.358824 -77.20215,162.608375 -77.20215,162.857926 -77.20215,163.107477 -77.20215,163.357028 -77.20215,163.606579 -77.20215,163.85613 -77.20215,163.85613 -77.291278,163.85613 -77.380406,163.85613 -77.469534,163.85613 -77.558662,163.85613 -77.64779,163.85613 -77.736918,163.85613 -77.826046,163.85613 -77.915174,163.85613 -78.004302,163.85613 -78.09343,163.606579 -78.09343,163.357028 -78.09343,163.107477 -78.09343,162.857926 -78.09343,162.608375 -78.09343,162.358824 -78.09343,162.109273 -78.09343,161.859722 -78.09343,161.610171 -78.09343,161.36062 -78.09343,161.36062 -78.004302,161.36062 -77.915174,161.36062 -77.826046,161.36062 -77.736918,161.36062 -77.64779,161.36062 -77.558662,161.36062 -77.469534,161.36062 -77.380406,161.36062 -77.291278,161.36062 -77.20215))", "dataset_titles": "Carbon-fixation rates and associated microbial communities; Carbon-fixation rates and associated microbial communities residing in arid and ephemerally wet Antarctic Dry Valley soils; Importance of Heterotrophic and Phototrophic N2 Fixation in the McMurdo Dry Valleys ; Microbial community composition of transiently wetted Antarctic Dry Valley soils.; Microbial population dynamics along a terrestrial Antarctic moisture gradient; Microbial population dynamics along a terrestrial wetted gradient", "datasets": [{"dataset_uid": "002738", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Carbon-fixation rates and associated microbial communities", "url": "https://www.ncbi.nlm.nih.gov/protein/?term=craig%20cary"}, {"dataset_uid": "200013", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Importance of Heterotrophic and Phototrophic N2 Fixation in the McMurdo Dry Valleys ", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA505820"}, {"dataset_uid": "002737", "doi": "", "keywords": null, "people": null, "repository": "KNB", "science_program": null, "title": "Carbon-fixation rates and associated microbial communities residing in arid and ephemerally wet Antarctic Dry Valley soils", "url": "https://knb.ecoinformatics.org/view/knb.756.1"}, {"dataset_uid": "200015", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Microbial community composition of transiently wetted Antarctic Dry Valley soils.", "url": "https://www.ncbi.nlm.nih.gov/popset/?term=KP836071%20to%20KP836108"}, {"dataset_uid": "002736", "doi": "", "keywords": null, "people": null, "repository": "EMBL", "science_program": null, "title": "Microbial population dynamics along a terrestrial Antarctic moisture gradient", "url": "https://www.ebi.ac.uk/ena/data/view/PRJEB27415"}, {"dataset_uid": "200014", "doi": "", "keywords": null, "people": null, "repository": "EMBL", "science_program": null, "title": "Microbial population dynamics along a terrestrial wetted gradient", "url": "https://www.ebi.ac.uk/ena/data/view/PRJEB7939"}], "date_created": "Wed, 14 Mar 2018 00:00:00 GMT", "description": "The McMurdo Dry Valleys in Antarctica are recognized as being the driest, coldest and probably one of the harshest environments on Earth. In addition to the lack of water, the biota in the valleys face a very limited supply of nutrients such as nitrogen compounds - necessary for protein synthesis. The glacial streams of the Dry Valleys have extensive cyanobacterial (blue green algae) mats that are a major source of carbon and nitrogen compounds to biota in this region. While cyanobacteria in streams are important as a source of these compounds, other non-photosynthetic bacteria also contribute a significant fraction (~50%) of fixed nitrogen compounds to valley biota. This research effort will involve an examination of exactly which non-phototrophic bacteria are involved in nitrogen fixation and what environmental factors are responsible for controlling nitrogen fixation by these microbes. This work will resolve the environmental factors that control the activity, abundance and diversity of nitrogen-fixing microbes across four of the McMurdo Dry Valleys. This will allow for comparisons among sites of differing latitude, temperature, elevation and exposure to water. These results will be integrated into a landscape wetness model that will help determine the impact of both cyanobacterial and non-photosynthetic nitrogen fixing microorganisms in this very harsh environment.\u003cbr/\u003e\u003cbr/\u003eThe Dry Valleys in many ways resemble the Martian environment, and understanding the primitive life and very simple nutrient cycling in the Dry Valleys has relevance for understanding how life might have once existed on other planets. Furthermore, the study of microbes from extreme environments has resulted in numerous biotechnological applications such as the polymerase chain reaction for amplifying DNA and mechanisms for freeze resistance in agricultural crops. Thus, this research should yield insights into how biota survive in extreme environments, and these insights could lead to other commercial applications.", "east": 163.85613, "geometry": "POINT(162.608375 -77.64779)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Antarctica; USAP-DC; RIVERS/STREAM", "locations": "Antarctica", "north": -77.20215, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cary, Stephen", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "EMBL; KNB; NCBI GenBank", "science_programs": null, "south": -78.09343, "title": "Collaborative Research: Importance of Heterotrophic and Phototrophic N2 Fixation in the McMurdo Dry Valleys on Local, Regional and Landscape Scales", "uid": "p0000235", "west": 161.36062}, {"awards": "1142108 Koch, Paul", "bounds_geometry": "POLYGON((-180 -55.1,-168.1 -55.1,-156.2 -55.1,-144.3 -55.1,-132.4 -55.1,-120.5 -55.1,-108.6 -55.1,-96.7 -55.1,-84.8 -55.1,-72.9 -55.1,-61 -55.1,-61 -57.4,-61 -59.7,-61 -62,-61 -64.3,-61 -66.6,-61 -68.9,-61 -71.2,-61 -73.5,-61 -75.8,-61 -78.1,-72.9 -78.1,-84.8 -78.1,-96.7 -78.1,-108.6 -78.1,-120.5 -78.1,-132.4 -78.1,-144.3 -78.1,-156.2 -78.1,-168.1 -78.1,180 -78.1,178.47 -78.1,176.94 -78.1,175.41 -78.1,173.88 -78.1,172.35 -78.1,170.82 -78.1,169.29 -78.1,167.76 -78.1,166.23 -78.1,164.7 -78.1,164.7 -75.8,164.7 -73.5,164.7 -71.2,164.7 -68.9,164.7 -66.6,164.7 -64.3,164.7 -62,164.7 -59.7,164.7 -57.4,164.7 -55.1,166.23 -55.1,167.76 -55.1,169.29 -55.1,170.82 -55.1,172.35 -55.1,173.88 -55.1,175.41 -55.1,176.94 -55.1,178.47 -55.1,-180 -55.1))", "dataset_titles": "Southern Ocean Pinnipeds", "datasets": [{"dataset_uid": "000242", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Southern Ocean Pinnipeds", "url": "https://www.bco-dmo.org/project/726874"}], "date_created": "Wed, 28 Feb 2018 00:00:00 GMT", "description": "Building on previously funded NSF research, the use of paleobiological and paleogenetic data from mummified elephant seal carcasses found along the Dry Valleys and Victoria Land Coast in areas that today are too cold to support seal colonies (Mirougina leonina; southern elephant seals; SES) supports the former existence of these seals in this region. The occurrence and then subsequent disappearance of these SES colonies is consistent with major shifts in the Holocene climate to much colder conditions at the last ~1000 years BCE). \u003cbr/\u003e\u003cbr/\u003eFurther analysis of the preserved remains of three other abundant pinnipeds ? crabeater (Lobodon carciophagus), Weddell (Leptonychotes weddelli) and leopard (Hydrurga leptonyx) will be studied to track changes in their population size (revealed by DNA analysis) and their diet (studied via stable isotope analysis). Combined with known differences in life history, preferred ice habitat and ecosystem sensitivity among these species, this paleoclimate proxy data will be used to assess their exposure and sensitivity to climate change in the Ross Sea region during the past ~1-2,000 years", "east": -61.0, "geometry": "POINT(-128.15 -66.6)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE", "locations": null, "north": -55.1, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Koch, Paul; Costa, Daniel; Hoelzel, A. Rus", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -78.1, "title": "Collaborative Research: Exploring the Vulnerability of Southern Ocean Pinnipeds to Climate Change - An Integrated Approach", "uid": "p0000410", "west": 164.7}, {"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": "1115245 McKnight, Diane", "bounds_geometry": "POLYGON((160.5 -77.35,160.83 -77.35,161.16 -77.35,161.49 -77.35,161.82 -77.35,162.15 -77.35,162.48 -77.35,162.81 -77.35,163.14 -77.35,163.47 -77.35,163.8 -77.35,163.8 -77.4,163.8 -77.45,163.8 -77.5,163.8 -77.55,163.8 -77.6,163.8 -77.65,163.8 -77.7,163.8 -77.75,163.8 -77.8,163.8 -77.85,163.47 -77.85,163.14 -77.85,162.81 -77.85,162.48 -77.85,162.15 -77.85,161.82 -77.85,161.49 -77.85,161.16 -77.85,160.83 -77.85,160.5 -77.85,160.5 -77.8,160.5 -77.75,160.5 -77.7,160.5 -77.65,160.5 -77.6,160.5 -77.55,160.5 -77.5,160.5 -77.45,160.5 -77.4,160.5 -77.35))", "dataset_titles": "McMurdo Dry Valleys LTER data at EDI Data Portal", "datasets": [{"dataset_uid": "000204", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys LTER data at EDI Data Portal", "url": "https://portal.edirepository.org/nis/browseServlet?searchValue=MCM "}], "date_created": "Mon, 08 Jan 2018 00:00:00 GMT", "description": "The McMurdo Dry Valleys (MDV) is a polar desert on the coast of East Antarctica, a region that has not yet experienced climate warming. The McMurdo Dry Valleys Long Term Ecological Research (MCMLTER) project has documented the ecological responses of the glacier, soil, stream and lake ecosystems in the MDV during a cooling trend (from 1986 to 2000) which was associated with the depletion of atmospheric ozone. In the past decade, warming events with strong katabatic winds occurred during two summers and the resulting high streamflows and sediment deposition changed the dry valley landscape, possibly presaging conditions that will occur when the ozone hole recovers. In anticipation of future warming in Antarctica, the overarching hypothesis of the proposed project is: Climate warming in the McMurdo Dry Valley ecosystem will amplify connectivity among landscape units leading to enhanced coupling of nutrient cycles across landscapes, and increased biodiversity and productivity within the ecosystem. Warming in the MDV is hypothesized to act as a slowly developing, long-term press of warmer summers, upon which transient pulse events of high summer flows and strong katabatic winds will be overprinted. Four specific hypotheses address the ways in which pulses of water and wind will influence contemporary and future ecosystem structure, function and connectivity. Because windborne transport of biota is a key aspect of enhanced connectivity from katabatic winds, new monitoring will include high-resolution measurements of aeolian particle flux. Importantly, integrative genomics will be employed to understand the responses of specific organisms to the increased connectivity. The project will also include a novel social science component that will use environmental history to examine interactions between human activity, scientific research, and environmental change in the MDV over the past 100 years. To disseminate this research broadly, MCM scientists will participate in a wide array of outreach efforts ranging from presentations in K-12 classrooms to bringing undergraduates and teachers to the MDV to gain research experience. Planned outreach programs will build upon activities conducted during the International Polar Year (2007-2008), which include development of an interactive DVD for high school students and teachers and publication of a children\u0027s book in the LTER Schoolyard Book Series. A teacher\u0027s edition of the book with a CD containing lesson plans will be distributed. The project will develop programs for groups traditionally underrepresented in science arenas by publishing some outreach materials in Spanish.", "east": 163.8, "geometry": "POINT(162.15 -77.6)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.35, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Instrumentation and Support; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "McKnight, Diane; Gooseff, Michael N.", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -77.85, "title": "Increased Connectivity in a Polar Desert Resulting from Climate Warming: McMurdo Dry Valley LTER Program", "uid": "p0000301", "west": 160.5}, {"awards": "1245749 Levy, Joseph; 1246342 Fountain, Andrew; 1246203 Gooseff, Michael", "bounds_geometry": "POLYGON((160.105465 -77.2119,160.7907435 -77.2119,161.476022 -77.2119,162.1613005 -77.2119,162.846579 -77.2119,163.5318575 -77.2119,164.217136 -77.2119,164.9024145 -77.2119,165.587693 -77.2119,166.2729715 -77.2119,166.95825 -77.2119,166.95825 -77.3189628,166.95825 -77.4260256,166.95825 -77.5330884,166.95825 -77.6401512,166.95825 -77.747214,166.95825 -77.8542768,166.95825 -77.9613396,166.95825 -78.0684024,166.95825 -78.1754652,166.95825 -78.282528,166.2729715 -78.282528,165.587693 -78.282528,164.9024145 -78.282528,164.217136 -78.282528,163.5318575 -78.282528,162.846579 -78.282528,162.1613005 -78.282528,161.476022 -78.282528,160.7907435 -78.282528,160.105465 -78.282528,160.105465 -78.1754652,160.105465 -78.0684024,160.105465 -77.9613396,160.105465 -77.8542768,160.105465 -77.747214,160.105465 -77.6401512,160.105465 -77.5330884,160.105465 -77.4260256,160.105465 -77.3189628,160.105465 -77.2119))", "dataset_titles": "2014-2015 lidar survey of the McMurdo Dry Valleys, Antarctica; Active Layer Temperatures from Crescent Stream banks, Taylor Valley Antarctica", "datasets": [{"dataset_uid": "601075", "doi": "10.15784/601075", "keywords": "Antarctica; Dry Valleys; Glaciology; Paleoclimate; Permafrost; Soil Temperature; Taylor Valley", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Active Layer Temperatures from Crescent Stream banks, Taylor Valley Antarctica", "url": "https://www.usap-dc.org/view/dataset/601075"}, {"dataset_uid": "000209", "doi": "", "keywords": null, "people": null, "repository": "OpenTopo", "science_program": null, "title": "2014-2015 lidar survey of the McMurdo Dry Valleys, Antarctica", "url": "http://opentopo.sdsc.edu/datasetMetadata?otCollectionID=OT.112016.3294.1"}], "date_created": "Wed, 20 Dec 2017 00:00:00 GMT", "description": "Collaborative Research: THE MCMURDO DRY VALLEYS: A Landscape on the Threshold of Change is supported by the Antarctic Integrated System Science (AISS) program in the Antarctic Sciences Section of the Division of Polar Programs within the Geosciences Directorate of the National Sciences Foundation (NSF). The funds will support the collection of state-of-the-art high resolution LIDAR (combining the terms light and radar) imagery of the Dry Valleys of Antarctica in the 2014/2015 Antarctic field season, with LIDAR data collection and processing being provided by the NSF-supported NCALM (National Center for Airborne Laser Mapping) facility. LIDAR images collected in 2014/2015 will be compared to images from 2001 in order to detect decadal change. Additional fieldwork will look at the distribution of buried massive ice, and the impacts that major changes like slumping are having on the biota. All field data will be used to improve models on energy balance, and hydrology.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit: There have been dramatic changes over the past decade in the McMurdo Dry Valleys: rivers are incising by more than three meters, and thermokarst slumps are appearing near several streams and lakes. These observations have all been made by researchers in the field, but none of the changes have been mapped on a valley-wide scale. This award will provide a new baseline map for the entire Dry Valley system, with high-resolution imagery provided for the valley floors, and lower resolution imagery available for the higher elevation areas that are undergoing less change. The project will test the idea that sediment-covered ice is associated with the most dramatic changes, due to differential impacts of the increased solar radiation on sediment-covered compared to clean ice, and despite the current trend of slightly cooling air temperatures within the Dry Valleys. Information collected on the topography, coupled with the GPR determined buried ice distributions, will also be incorporated into improved energy and hydrological models. In addition to providing the new high-resolution digital elevation model (DEM), the project will ultimately result in identification of areas that are susceptible to sediment-enhanced melt-driven change, providing a powerful prediction tool for the impacts of climate change.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts: The new DEM will be immediately useful to a wide range of disciplines, and will provide a comprehensive new baseline against which future changes will be compared. The project will provide a tool for the whole community to use, and the investigators will work with the community to make them aware of the new assets via public presentations, and perhaps via a workshop. The map will have international interest, and will also serve as a tool for environmental managers to draw on as they consider conservation plans. Several undergraduate and graduate students will participate in the project, and one of the co-PIs is a new investigator. The imagery collected is expected to be of interest to the general public in addition to scientific researchers, and venues for outreach such as museum exhibits and the internet will be explored. The proposed work is synergistic with 1) the co-located McMurdo LTER program, and 2) the NCALM facility that is also funded by the Geosciences Directorate.", "east": 166.95825, "geometry": "POINT(163.5318575 -77.747214)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e AIRBORNE LASER SCANNER", "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; Not provided; LANDFORMS; NOT APPLICABLE", "locations": "Antarctica", "north": -77.2119, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Levy, Joseph; Gooseff, Michael N.; Fountain, Andrew", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "OpenTopo; USAP-DC", "science_programs": null, "south": -78.282528, "title": "Collaborative Research: THE MCMURDO DRY VALLEYS: A landscape on the Threshold of Change", "uid": "p0000076", "west": 160.105465}, {"awards": "1344349 Tulaczyk, Slawek; 1344348 Mikucki, Jill", "bounds_geometry": null, "dataset_titles": "2011 Time-domain ElectroMagnetics data for McMurdo Dry Valleys; Marinobacter lipolyticus BF04_CF-4 genomic scaffold, whole genome shotgun sequence; Marinobacter sp. BF14_3D 16S ribosomal RNA gene, partial sequence", "datasets": [{"dataset_uid": "601071", "doi": "10.15784/601071", "keywords": "Antarctica; Dry Valleys; Electromagnetic Data; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; McMurdo", "people": "Tulaczyk, Slawek", "repository": "USAP-DC", "science_program": null, "title": "2011 Time-domain ElectroMagnetics data for McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601071"}, {"dataset_uid": "000197", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Marinobacter lipolyticus BF04_CF-4 genomic scaffold, whole genome shotgun sequence", "url": "https://www.ncbi.nlm.nih.gov/nuccore?term=PRJNA165567"}, {"dataset_uid": "000196", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Marinobacter sp. BF14_3D 16S ribosomal RNA gene, partial sequence", "url": "https://www.ncbi.nlm.nih.gov/nuccore/KX364066"}], "date_created": "Wed, 08 Nov 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe MCM-SkyTEM project mapped resistivity in the McMurdo Dry Valleys and at Cape Barne on the Ross Island during the 2011-12 austral season using an airborne transient electromagnetic method. The SkyTEM system is mounted to a helicopter enabling a broad geophysical survey of subsurface resistivity structure over terrain that is inaccessible to traditional ground-based methods. Resistivity measurements obtained distinguish between highly resistive geologic materials such as glacier ice, bedrock and permafrost, and conductive materials such as unfrozen sediments or permafrost with liquid brine to depths of about 300 m. The PIs request funding to derive data products relevant to physical and chemical conditions in potential subsurface microbial habitats of the McMurdo Dry Valleys, similar cold regions on Earth and other planetary bodies. They will use these data products to characterize the hydrologic history of McMurdo Dry Valleys as well as the subsurface hydrologic connectivity in the region to investigate the implications for nutrient and microbial transport. The PIs will make these data products accessible to the research community. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003ePolar microbial habitats are of high societal and scientific interest because they represent important testing grounds for the limits of life on Earth and other planetary bodies. Project deliverables will include teaching aids for undergraduate and graduate students. Two Ph.D. students will obtain advanced research training as part of this project. The PIs and students on this project will also engage in informal public outreach opportunities by presenting at local K-12 schools and reaching out to local media outlets on stories relating to SkyTEM research.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Tulaczyk, Slawek; Mikucki, Jill", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "NCBI GenBank; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: EAGER: Processing, Interpretation and Dissemination of the Proof-of-Concept Transient Electromagnetic Survey of the McMurdo Dry Valleys Region", "uid": "p0000329", "west": null}, {"awards": "1341712 Hallet, Bernard", "bounds_geometry": "POLYGON((160.9 -76.7,161.08 -76.7,161.26 -76.7,161.44 -76.7,161.62 -76.7,161.8 -76.7,161.98 -76.7,162.16 -76.7,162.34 -76.7,162.52 -76.7,162.7 -76.7,162.7 -76.79,162.7 -76.88,162.7 -76.97,162.7 -77.06,162.7 -77.15,162.7 -77.24,162.7 -77.33,162.7 -77.42,162.7 -77.51,162.7 -77.6,162.52 -77.6,162.34 -77.6,162.16 -77.6,161.98 -77.6,161.8 -77.6,161.62 -77.6,161.44 -77.6,161.26 -77.6,161.08 -77.6,160.9 -77.6,160.9 -77.51,160.9 -77.42,160.9 -77.33,160.9 -77.24,160.9 -77.15,160.9 -77.06,160.9 -76.97,160.9 -76.88,160.9 -76.79,160.9 -76.7))", "dataset_titles": "Long-term rock abrasion study in the Dry Valleys", "datasets": [{"dataset_uid": "601060", "doi": "10.15784/601060", "keywords": "Antarctica; Dry Valleys; Geology/Geophysics - Other; Rocks", "people": "Hallet, Bernard; Malin, Michael; Sletten, Ronald S.", "repository": "USAP-DC", "science_program": null, "title": "Long-term rock abrasion study in the Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601060"}], "date_created": "Fri, 13 Oct 2017 00:00:00 GMT", "description": "Many of the natural processes that modify the landscape inhabited by humans occur over very long timescales, making them difficult to observe. Exceptions include rare catastrophic events such as earthquakes, volcanic eruptions, and floods that occur on short timescales. Many significant processes that affect the land and landscape that we inhabit operate on time scales imperceptible to humans. One of these processes is wind transport of sand, with related impacts to exposed rock surfaces and man-made objects, including buildings, windshields, solar panels and wind-farm turbine blades. The goal of this project is to gain an understanding of wind erosion processes over long timescales, in the Antarctic Dry Valleys, a cold desert environment where there were no competing processes (such as rain and vegetation) that might mask the effects. The main objective is recovery of rock samples that were deployed in 1983/1984 at 11 locations in the Antarctic Dry Valleys, along with measurements on the rock samples and characterization of the sites. In the late 1980s and early 1990s some of these samples were returned and indicated more time was needed to accumulate information about the timescales and impacts of the wind erosion processes. This project will allow collection of the remaining samples from this experiment after 30 to 31 years of exposure. The field work will be carried out during the 2014/15 Austral summer. The results will allow direct measurement of the abrasion rate and hence the volumes and timescales of sand transport; this will conclude the longest direct examination of such processes ever conducted. Appropriate scaling of the results may be applied to buildings, vegetation (crops), and other aspects of human presence in sandy and windy locations, in order to better determine the impact of these processes and possible mitigation of the impacts. The project is a collaborative effort between a small business, Malin Space Science Systems (MSSS), and the University of Washington (UW). MSSS will highlight this Antarctic research on its web site, by developing thematic presentations describing our research and providing a broad range of visual materials. The public will be engaged through daily updates on a website and through links to material prepared for viewing in Google Earth. UW students will be involved in the laboratory work and in the interpretation of the results.\u003cbr\u003eTechnical Description of Project:\u003cbr\u003eThe goal of this project is to study the role of wind abrasion by entrained particles in the evolution of the McMurdo Dry Valleys in the Transantarctic Mountains. During the 1983 to 1984 field seasons, over 5000 rock targets were installed at five heights facing the 4 cardinal directions at 10 locations (with an additional site containing fewer targets) to study rates of physical weathering due primarily to eolian abrasion. In addition, rock cubes and cylinders were deployed at each site to examine effects of chemical weathering. The initial examination of samples returned after 1, 5, and 10 years of exposure, showed average contemporary abrasion rates consistent with those determined by cosmogenic isotope studies, but further stress that \"average\" should not be interpreted as meaning \"uniform.\" The samples will be characterized using mass measurements wtih 0.01 mg precision balances, digital microphotography to compare the evolution of their surface features and textures, SEM imaging to examine the micro textures of abraded rock surfaces, and optical microscopy of thin sections of a few samples to examine the consequences of particle impacts extending below the abraded surfaces. As much as 60-80% of the abrasion measured in samples from 1984-1994 appears to have occurred during a few brief hours in 1984. This is consistent with theoretical models that suggest abrasion scales as the 5th power of wind velocity. The field work will allow return of multiple samples after three decades of exposure, which will provide a statistical sampling (beyond what is acquired by studying a single sample), and will yield the mass loss data in light of complementary environmental and sand kinetic energy flux data from other sources (e.g. LTER meteorology stations). This study promises to improve insights into one of the principal active geomorphic process in the Dry Valleys, an important cold desert environment, and the solid empirical database will provide general constraints on eolian abrasion under natural conditions.", "east": 162.7, "geometry": "POINT(161.8 -77.15)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.7, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Hallet, Bernard; Sletten, Ronald S.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.6, "title": "Collaborative Proposal: Decades-long Experiment on Wind-Driven Rock Abrasion in the Ice-Free Valleys, Antarctica", "uid": "p0000074", "west": 160.9}, {"awards": "1341284 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.5,161.2 -77.5,161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163 -77.525,163 -77.55,163 -77.575,163 -77.6,163 -77.625,163 -77.65,163 -77.675,163 -77.7,163 -77.725,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,161.8 -77.75,161.6 -77.75,161.4 -77.75,161.2 -77.75,161 -77.75,161 -77.725,161 -77.7,161 -77.675,161 -77.65,161 -77.625,161 -77.6,161 -77.575,161 -77.55,161 -77.525,161 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Oct 2017 00:00:00 GMT", "description": "Paragraph for Laypersons:\u003cbr/\u003eThis research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations.\u003cbr/\u003e\u003cbr/\u003eParagraph for Scientific Community:\u003cbr/\u003eRock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure\u003cbr/\u003edating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.", "east": 163.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.75, "title": "Origin and Climatic Significance of Rock Glaciers in the McMurdo Dry Valleys: Assessing Spatial and Temporal Variability", "uid": "p0000297", "west": 161.0}, {"awards": "1553824 Heine, John", "bounds_geometry": "POINT(166.667 -77.85)", "dataset_titles": "Rebreather Testing for the United States Antarctic Scientific Diving Program", "datasets": [{"dataset_uid": "601024", "doi": "10.15784/601024", "keywords": "Antarctica; Diving; Global; Physical Oceanography", "people": "Heine, John", "repository": "USAP-DC", "science_program": null, "title": "Rebreather Testing for the United States Antarctic Scientific Diving Program", "url": "https://www.usap-dc.org/view/dataset/601024"}], "date_created": "Fri, 26 May 2017 00:00:00 GMT", "description": "There are a number of areas of Antarctic research by scientists from the United States where rebreather technology (which unlike normal SCUBA diving releases few if any air bubbles) would be valuable tools. These include but are not limited to behavioral studies (because noise from bubbles released by standard SCUBA alters the behavior of many marine organisms), studies of communities on the underside of sea ice (because the bubbles disrupt the communities while or before they are sampled), and studies of highly stratified lake communities (because the bubbles cause mixing and because lighter line could be used to tether a diver to the surface which would probably also cause less water column disruption). The latter scientific advantage of less mixing in highly stratified (not naturally mixed) lakes is also a significant environmental advantage of rebreathers. However, for safety reasons, no US science projects will be approved for the use of rebreathers until they are tested by the US Antarctic Program (USAP). This award provides funds for the USAP Scientific Diving Officer to conduct such tests in conjunction with other diving professionals experienced in polar diving in general and specifically with rebreather technology in non-polar environments. A team of six scientific diving professionals will evaluate seven or more commercial rebreather models that are being most commonly used in non-polar scientific diving. This will be done through holes drilled or melted in sea ice at McMurdo Station, Antarctica. A limited number of test dives of the best performing models will subsequently be made in stratified lakes in the McMurdo Dry Valleys.", "east": 166.667, "geometry": "POINT(166.667 -77.85)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.85, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Heine, John", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.85, "title": "Rebreather Testing for the United States Antarctic Scientific Diving Program", "uid": "p0000377", "west": 166.667}, {"awards": "1340905 Doran, Peter", "bounds_geometry": "POLYGON((161 -77,161.3 -77,161.6 -77,161.9 -77,162.2 -77,162.5 -77,162.8 -77,163.1 -77,163.4 -77,163.7 -77,164 -77,164 -77.05,164 -77.1,164 -77.15,164 -77.2,164 -77.25,164 -77.3,164 -77.35,164 -77.4,164 -77.45,164 -77.5,163.7 -77.5,163.4 -77.5,163.1 -77.5,162.8 -77.5,162.5 -77.5,162.2 -77.5,161.9 -77.5,161.6 -77.5,161.3 -77.5,161 -77.5,161 -77.45,161 -77.4,161 -77.35,161 -77.3,161 -77.25,161 -77.2,161 -77.15,161 -77.1,161 -77.05,161 -77))", "dataset_titles": "Lake Bonney Autonomous Lake Profiler and Samplers (ALPS): Particulate Organic Carbon and Nitrogen Concentrations. doi:10.6073/pasta/0043c1728b4e51879970d59f2d0ce575", "datasets": [{"dataset_uid": "002521", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "Lake Bonney Autonomous Lake Profiler and Samplers (ALPS): Particulate Organic Carbon and Nitrogen Concentrations. doi:10.6073/pasta/0043c1728b4e51879970d59f2d0ce575", "url": "http://www.mcmlter.org/node/3957"}], "date_created": "Fri, 13 Jan 2017 00:00:00 GMT", "description": "EAGER: Collaborative Research: Habitability of Antarctic lakes and detectability of microbial life in icy environments by autonomous year-round instrumentation, is supported by the Antarctic Integrated System Science (AISS) and the Antarctic Organisms and Ecosystems (AOE) programs within the Antarctic Sciences section in the Division of Polar Programs within the Geosciences Directorate of the National Sciences Foundation (NSF). The funds will allow the measurement of year-round properties of the microbes and the surrounding water in Lake Bonney, a lake with four meters of permanent ice cover over forty meters of liquid water in the Dry Valleys of Antarctica. NSF funds will be used to support the deployment, and the science enabled by the deployment, and NASA (the National Aeronautics and Space Administration) funds will be used to purchase the equipment.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit: This research will be the first to make year-round measurements of the microbial community, and several associated environmental variables, in the continuously liquid portions of Lake Bonney, Antarctica. Three different types of equipment will be deployed in each of the lobes of Lake Bonney. The first instrument is an ITP (an ice-tethered profiler) that will measure physical parameters such as temperature, dissolved oxygen, and chlorophyll throughout the full depth of the liquid water portion of the lake, making measurements at least once each week. The second and third instruments will be used to collect discrete water samples at least every two weeks to determine A) the biological community (assessing metabolic and phylogenetic diversity) and B) the geochemistry (e.g., dissolved organic carbon, and dissolved inorganic nitrogen species). Such samplers have never been used to measure these properties year-round in the Antarctic. Cold temperatures, bottom lake water salinities that are four times greater than the ocean, the thick permanent ice cover, and the lack of sunlight to recharge batteries all present significant challenges for the project, thus classifying the work as an early, high-risk, high-reward activity (the acronym EAGER stands for Early-concept Grants for Exploratory Research).\u003cbr/\u003e\u003cbr/\u003eBroader Impacts: There is much interest in understanding the ecosystems of the Polar regions in an era of climate change. Logistical limitations dictate much of this work only take place in the summer, until new autonomous technologies can open the door for year-round measurements. This award will be the first to attempt year-round microbial sampling in Antarctica. The McMurdo Dry Valleys region is also the site of a Long-Term Ecological Research (LTER) Program, and the research conducted on this project with benefit from, and contribute to, the larger LTER project. The instruments used in the project will be purchased by NASA, so two separate agencies have agreed to explore the feasibility of an early stage project. There will be at least three graduate student trained during the project, and the team will also participate in outreach activities at several venues including the Crow Reservation in Montana.", "east": 164.0, "geometry": "POINT(162.5 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Doran, Peter; Takacs-Vesbach, Cristina; Priscu, John", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -77.5, "title": "EAGER: Collaborative Research: Habitability of Antarctic Lakes and Detectability of Microbial Life in Icy Environments by Aautonomous Year-round Instrumentation", "uid": "p0000326", "west": 161.0}, {"awards": "1142096 Schwartz, Egbert; 1142102 Takacs-Vesbach, Cristina", "bounds_geometry": "POLYGON((161 -77,161.3 -77,161.6 -77,161.9 -77,162.2 -77,162.5 -77,162.8 -77,163.1 -77,163.4 -77,163.7 -77,164 -77,164 -77.05,164 -77.1,164 -77.15,164 -77.2,164 -77.25,164 -77.3,164 -77.35,164 -77.4,164 -77.45,164 -77.5,163.7 -77.5,163.4 -77.5,163.1 -77.5,162.8 -77.5,162.5 -77.5,162.2 -77.5,161.9 -77.5,161.6 -77.5,161.3 -77.5,161 -77.5,161 -77.45,161 -77.4,161 -77.35,161 -77.3,161 -77.25,161 -77.2,161 -77.15,161 -77.1,161 -77.05,161 -77))", "dataset_titles": "GenBank. Accession # PRJNA232062,PRJNA228947,PRJNA228945; McMurdo Dry Valleys LTER Genetic/Genomic Data Resource; NCBI GenBank RNA sequences", "datasets": [{"dataset_uid": "000177", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "NCBI GenBank RNA sequences", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA356879"}, {"dataset_uid": "000180", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys LTER Genetic/Genomic Data Resource", "url": "http://www.mcmlter.org/genetic"}, {"dataset_uid": "000178", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "GenBank. Accession # PRJNA232062,PRJNA228947,PRJNA228945", "url": "http://www.ncbi.nlm.nih.gov/genbank/"}], "date_created": "Wed, 04 Jan 2017 00:00:00 GMT", "description": "The McMurdo Dry Valleys in Antarctica are among the coldest, driest habitats on the planet. Previous research has documented the presence of surprisingly diverse microbial communities in the soils of the Dry Valleys despite these extreme conditions. However, the degree to which these organisms are active is unknown; it is possible that much of this diversity reflects microbes that have blown into this environment that are subsequently preserved in these cold, dry conditions. This research will use modern molecular techniques to answer a fundamental question regarding these communities: which organisms are active and how do they live in such extreme conditions? The research will include manipulations to explore how changes in water, salt and carbon affect the microbial community, to address the role that these organisms play in nutrient cycling in this environment. The results of this work will provide a broader understanding of how life adapts to such extreme conditions as well as the role of dormancy in the life history of microorganisms. Results will be widely disseminated through publications as well as through presentations at national and international meetings; raw data will be made available through a high-profile web-based portal. The research will support two graduate students, two undergraduate research assistants and a postdoctoral fellow. The results will be incorporated into a webinar targeted to secondary and post-secondary educators and a complimentary hands-on class activity kit will be developed and made available to various teacher and outreach organizations.", "east": 164.0, "geometry": "POINT(162.5 -77.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Takacs-Vesbach, Cristina; Schwartz, Egbert; Van Horn, David", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "LTER; NCBI GenBank", "science_programs": "LTER", "south": -77.5, "title": "Collaborative Research: An Integrated Ecological Investigation of McMurdo Dry Valley\u0027s Active Soil Microbial Communities", "uid": "p0000334", "west": 161.0}, {"awards": "1043724 Swanger, Kate", "bounds_geometry": "POLYGON((160.3 -77.4,160.52 -77.4,160.74 -77.4,160.96 -77.4,161.18 -77.4,161.4 -77.4,161.62 -77.4,161.84 -77.4,162.06 -77.4,162.28 -77.4,162.5 -77.4,162.5 -77.44,162.5 -77.48,162.5 -77.52,162.5 -77.56,162.5 -77.6,162.5 -77.64,162.5 -77.68,162.5 -77.72,162.5 -77.76,162.5 -77.8,162.28 -77.8,162.06 -77.8,161.84 -77.8,161.62 -77.8,161.4 -77.8,161.18 -77.8,160.96 -77.8,160.74 -77.8,160.52 -77.8,160.3 -77.8,160.3 -77.76,160.3 -77.72,160.3 -77.68,160.3 -77.64,160.3 -77.6,160.3 -77.56,160.3 -77.52,160.3 -77.48,160.3 -77.44,160.3 -77.4))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 05 Dec 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.", "east": 162.5, "geometry": "POINT(161.4 -77.6)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.4, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.8, "title": "Collaborative Research: Multi-nuclide approach to systematically evaluate the scatter in surface exposure ages in Antarctica and to develop consistent alpine glacier chronologies", "uid": "p0000406", "west": 160.3}, {"awards": "1144224 Marchant, David", "bounds_geometry": "POLYGON((160 -71.5,161 -71.5,162 -71.5,163 -71.5,164 -71.5,165 -71.5,166 -71.5,167 -71.5,168 -71.5,169 -71.5,170 -71.5,170 -72.15,170 -72.8,170 -73.45,170 -74.1,170 -74.75,170 -75.4,170 -76.05,170 -76.7,170 -77.35,170 -78,169 -78,168 -78,167 -78,166 -78,165 -78,164 -78,163 -78,162 -78,161 -78,160 -78,160 -77.35,160 -76.7,160 -76.05,160 -75.4,160 -74.75,160 -74.1,160 -73.45,160 -72.8,160 -72.15,160 -71.5))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 23 Oct 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose a two-year project to map the distribution of climate-sensitive landforms throughout Northern Victoria Land between the Convoy Range and Cape Adare. This work will produce geospatial products to aid their geomorphic work on ice sheet stability and landscape evolution. Specifically, the PI will investigate the potential for extensive surface melting and ice-sheet retreat with modest warming in areas north of the Convoy Range in Northern Victoria Land. The hypothesis is that if key landform elements of the Dry Valleys assemblage are lacking in NVL it suggests a major variation in current climate conditions, and perhaps changes in climate evolution. The proposed work will also benefit the broader research community, as it will demonstrate the potential for using geospatial imagery in geomorphic research and produce geospatial products that can be used by other researchers. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis work will help the research community better leverage the investment being made in the Polar Geospatial Center (PGC) and will help further demonstrate the significance of satellite imagery for doing ?virtual? field work in the Polar regions. More effective use of satellite imagery by field scientists in Antarctica will help reduce the logistical footprint on the Continent. The proposed research will support one graduate student at Boston University who will be trained in image analysis, map production, Antarctic geomorphology, and geospatial technologies. The proposed work will help to forge stronger links between PGC and Boston University?s Digital Image Analyses Lab (DIAL).", "east": 170.0, "geometry": "POINT(165 -74.75)", "instruments": null, "is_usap_dc": false, "keywords": "Bu/es Data Repository; Not provided", "locations": null, "north": -71.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marchant, David", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.0, "title": "Geomorphic investigations of Northern Victoria Land, Antarctica", "uid": "p0000231", "west": 160.0}, {"awards": "1043706 Marchant, David", "bounds_geometry": "POLYGON((160 -76.5,160.45 -76.5,160.9 -76.5,161.35 -76.5,161.8 -76.5,162.25 -76.5,162.7 -76.5,163.15 -76.5,163.6 -76.5,164.05 -76.5,164.5 -76.5,164.5 -76.7,164.5 -76.9,164.5 -77.1,164.5 -77.3,164.5 -77.5,164.5 -77.7,164.5 -77.9,164.5 -78.1,164.5 -78.3,164.5 -78.5,164.05 -78.5,163.6 -78.5,163.15 -78.5,162.7 -78.5,162.25 -78.5,161.8 -78.5,161.35 -78.5,160.9 -78.5,160.45 -78.5,160 -78.5,160 -78.3,160 -78.1,160 -77.9,160 -77.7,160 -77.5,160 -77.3,160 -77.1,160 -76.9,160 -76.7,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 23 Oct 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": false, "keywords": "McMurdo Dry Valleys; Rock Weathering; Not provided", "locations": "McMurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marchant, David", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.5, "title": "Collaborative Research: Multi-nuclide approach to systematically evaluate the scatter in surface exposure ages in Antarctica and to develop consistent alpine glacier chronologies", "uid": "p0000269", "west": 160.0}, {"awards": "1343649 Levy, Joseph", "bounds_geometry": "POLYGON((162.852 -77.6111,162.9893 -77.6111,163.1266 -77.6111,163.2639 -77.6111,163.4012 -77.6111,163.5385 -77.6111,163.6758 -77.6111,163.8131 -77.6111,163.9504 -77.6111,164.0877 -77.6111,164.225 -77.6111,164.225 -77.65331,164.225 -77.69552,164.225 -77.73773,164.225 -77.77994,164.225 -77.82215,164.225 -77.86436,164.225 -77.90657,164.225 -77.94878,164.225 -77.99099,164.225 -78.0332,164.0877 -78.0332,163.9504 -78.0332,163.8131 -78.0332,163.6758 -78.0332,163.5385 -78.0332,163.4012 -78.0332,163.2639 -78.0332,163.1266 -78.0332,162.9893 -78.0332,162.852 -78.0332,162.852 -77.99099,162.852 -77.94878,162.852 -77.90657,162.852 -77.86436,162.852 -77.82215,162.852 -77.77994,162.852 -77.73773,162.852 -77.69552,162.852 -77.65331,162.852 -77.6111))", "dataset_titles": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "600139", "doi": "10.15784/600139", "keywords": "Antarctica; Chemistry:soil; Chemistry:Soil; Critical Zone; Dry Valleys; Permafrost; Sample/collection Description; Sample/Collection Description; Well Measurements", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600139"}], "date_created": "Mon, 05 Oct 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to quantify the hillslope water, solute, and carbon budgets for Taylor Valley in the McMurdo Dry Valleys, using water tracks to investigate near-surface geological processes and challenge the paradigm that shallow groundwater is minimal or non-exixtant. Water tracks are linear zones of high soil moisture that route shallow groundwater downslope in permafrost dominated soils. Four hypotheses will be tested: 1) water tracks are important pathways for water and solute transport; 2) water tracks transport more dissolved silica than streams in Taylor Valley indicating they are the primary site of chemical weathering for cold desert soils and bedrock; 3) water tracks that drain highland terrains are dominated by humidity-separated brines while water tracks that drain lowland terrains are dominated by marine aerosols; 4) water tracks are the sites of the highest terrestrial soil carbon concentrations and the strongest CO2 fluxes in Taylor Valley and their carbon content increases with soil age, while carbon flux decreases with age. To test these hypotheses the PIs will carry out a suite of field measurements supported by modeling and remote sensing. They will install shallow permafrost wells in water tracks that span the range of geological, climatological, and topographic conditions in Taylor Valley. Multifrequency electromagnetic induction sounding of the upper ~1 m of the permafrost will create the first comprehensive map of soil moisture in Taylor Valley, and will permit direct quantification of water track discharge across the valley. The carbon contents of water track soils will be measured and linked to global carbon dynamics.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eNon-science majors at Oregon State University will be integrated into the proposed research through a new Global Environmental Change course focusing on the scientific method in Antarctica. Three undergraduate students, members of underrepresented minorities, will be entrained in the research, will contribute to all aspects of field and laboratory science, and will present results at national meetings.", "east": 164.225, "geometry": "POINT(163.5385 -77.82215)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.6111, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Levy, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0332, "title": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "uid": "p0000407", "west": 162.852}, {"awards": "0944556 Barrett, John", "bounds_geometry": "POLYGON((160.6015 -76.9089,161.7382 -76.9089,162.8749 -76.9089,164.0116 -76.9089,165.1483 -76.9089,166.285 -76.9089,167.4217 -76.9089,168.5584 -76.9089,169.6951 -76.9089,170.8318 -76.9089,171.9685 -76.9089,171.9685 -77.73527,171.9685 -78.56164,171.9685 -79.38801,171.9685 -80.21438,171.9685 -81.04075,171.9685 -81.86712,171.9685 -82.69349,171.9685 -83.51986,171.9685 -84.34623,171.9685 -85.1726,170.8318 -85.1726,169.6951 -85.1726,168.5584 -85.1726,167.4217 -85.1726,166.285 -85.1726,165.1483 -85.1726,164.0116 -85.1726,162.8749 -85.1726,161.7382 -85.1726,160.6015 -85.1726,160.6015 -84.34623,160.6015 -83.51986,160.6015 -82.69349,160.6015 -81.86712,160.6015 -81.04075,160.6015 -80.21438,160.6015 -79.38801,160.6015 -78.56164,160.6015 -77.73527,160.6015 -76.9089))", "dataset_titles": "Ecosphere (Supplement), Ecological Society of America.", "datasets": [{"dataset_uid": "002538", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Ecosphere (Supplement), Ecological Society of America.", "url": "http://www.esapubs.org/archive/ecos/C004/014/suppl-1.php"}], "date_created": "Fri, 13 Feb 2015 00:00:00 GMT", "description": "Advances in molecular techniques have expanded our understanding of soil microbial communities, and raised important questions about regional and global patterns in microbial diversity. The proposed research will investigate the composition and activity of microbial communities across a range of geochemical and hydrologic soil conditions, and over local to regional scales in the Transantarctic Mountains, in order to assess controls over microbial biogeography. The research targets two areas in the Transantarctic mountains, the McMurdo Dry Valleys, and the Beardmore Glacier region further south, the latter representing an underexplored and inarguably more extreme soil environment. The research project will adopt an integrated approach, using molecular techniques and in situ assessment of biological activity in a quantitative biogeographical framework, with the goal of distinguishing fine versus broad scale controls over microbial community structure. The research is essential to determining the basic trophic status of extreme microbial food webs, and their sensitivity to climate change. The investigators will engage secondary and post-secondary educators through first person outreach as well as web-based communications and exercises. Two postdoctoral scientists will be trained in an interdisciplinary and international setting.", "east": 171.9685, "geometry": "POINT(166.285 -81.04075)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.9089, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Barrett, John", "platforms": "Not provided", "repo": "Publication", "repositories": "Publication", "science_programs": null, "south": -85.1726, "title": "Collaborative Research: Controls over the Spatial Distribution and Activity of Microbial Communities in Antarctic Soils", "uid": "p0000350", "west": 160.6015}, {"awards": "1354231 Kowalewski, Douglas", "bounds_geometry": "POLYGON((-180 -70,-174 -70,-168 -70,-162 -70,-156 -70,-150 -70,-144 -70,-138 -70,-132 -70,-126 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-126 -85,-132 -85,-138 -85,-144 -85,-150 -85,-156 -85,-162 -85,-168 -85,-174 -85,180 -85,178 -85,176 -85,174 -85,172 -85,170 -85,168 -85,166 -85,164 -85,162 -85,160 -85,160 -83.5,160 -82,160 -80.5,160 -79,160 -77.5,160 -76,160 -74.5,160 -73,160 -71.5,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "datasets": [{"dataset_uid": "600140", "doi": "10.15784/600140", "keywords": "Antarctica; Atmosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Model Data; Paleoclimate; Transantarctic Mountains", "people": "Kowalewski, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/600140"}], "date_created": "Thu, 28 Aug 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eNeogene sediment records recovered by ANDRILL suggest multiple events of open water conditions and elevated sea surface temperatures at times when terrestrial data from the McMurdo Dry Valleys indicate hyper arid, cold, desert conditions. Interpretation of the ANDRILL data suggests the West Antarctic Ice Sheet is highly sensitive to changes in Pliocene sea surface temperatures and this conclusion has been supported by recent Global Circulation Model results for the early to mid Pliocene. The PIs propose to model paleo-ice configurations and warm orbits associated with a WAIS collapse to assess potential climate change in East Antarctica. During such episodes of polar warmth they propose to answer: What is the limit of ablation along the East Antarctic Ice Sheet?; Are relict landforms in the Dry Valleys susceptible to modification from increase in maximum summertime temperatures?; and Is there sufficient increase in minimum wintertime temperatures to sustain a tundra environment in the Dry Valleys? Integration of depositional records and model outputs have the potential to test the performance of numerical models currently under development as part of ANDRILL; reconcile inconsistencies between marine and terrestrial paleoclimate records in high Southern Latitudes; and improve understanding of Antarctic climate and ice volume sensitivity to forcing for both the East Antarctic and West Antarctic Ice Sheets. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eResults from this study have the potential to be used widely by the research community. Outreach to local elementary schools from other funded efforts will continue and be extended to homeschooled students. A Post Doc will be supported as part of this award.", "east": -120.0, "geometry": "POINT(-160 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kowalewski, Douglas", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "uid": "p0000463", "west": 160.0}, {"awards": "1045215 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": "Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "datasets": [{"dataset_uid": "600131", "doi": "10.15784/600131", "keywords": "Antarctica; Climate; Critical Zone; Dry Valleys; Radar; Soil Moisture", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "url": "https://www.usap-dc.org/view/dataset/600131"}], "date_created": "Tue, 01 Jul 2014 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eUntil recently, wetted soils in the Dry Valleys were generally only found adjacent to streams and lakes. Since the warm austral summer of 2002, numerous ?wet spots? have been observed far from shorelines on relatively flat valley floor locations and as downslope fingers of flow on valley walls. The source of the water to wet these soils is unclear, as is the spatial and temporal pattern of occurrence from year to year. Their significance is potentially great as enhanced soil moisture may change the thermodynamics, hydrology, and erosion rate of surface soils, and facilitate transport of materials that had previously been stable. These changes to the soil active layer could significantly modify permafrost and ground ice stability within the Dry Valleys. The PIs seek to investigate these changes to address two competing hypotheses: that the source of water to these ?wet spots? is ground ice melt and that the source of this water is snowmelt. The PIs will document the spatiotemporal dynamics of these wet areas using high frequency remote sensing data from Quickbird and Wordview satellites to document the occurrence, dimensions, and growth of wet spots during the 2010-\u00c2\u00ad11 and 2011-\u00c2\u00ad12 austral summers. They will test their hypotheses by determining whether wet spots recur in the same locations in each season, and they will compare present to past distribution using archived imagery. They will also determine whether spatial snow accumulation patterns and temporal ablation patterns are coincident with wet spot formation. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eOne graduate student will be trained on this project. Findings will be reported at scientific meetings and published in peer reviewed journals. They will also develop a teaching module on remote sensing applications to hydrology for the Modular Curriculum for Hydrologic Advancement and an innovative prototype project designed to leverage public participation in mapping wet spots and snow patches across the Dry Valleys through the use of social media and mobile computing applications.", "east": 165.0, "geometry": "POINT(162.5 -77.875)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; USAP-DC; ANALYTICAL LAB; Amd/Us", "locations": null, "north": -77.25, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Gooseff, Michael N.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "EAGER: Are the Dry Valleys Getting Wetter? A Preliminary Assessment of Wetness Across the McMurdo Dry Valleys Landscape", "uid": "p0000471", "west": 160.0}, {"awards": "0739698 Doran, Peter; 0739681 Murray, Alison", "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": "0739648 Cary, Stephen", "bounds_geometry": "POINT(163 -77.5)", "dataset_titles": "Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams", "datasets": [{"dataset_uid": "600079", "doi": "10.15784/600079", "keywords": "Antarctica; Biota; Cell Counts; Dry Valleys; Microbiology", "people": "Cary, S. Craig", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams", "url": "https://www.usap-dc.org/view/dataset/600079"}], "date_created": "Tue, 10 Dec 2013 00:00:00 GMT", "description": "The glacial streams of the McMurdo Dry Valleys have extensive cyanobacterial mats that are a probable source of fixed C and N to the Valleys. The research will examine the interplay between the microbial mats in the ephemeral glacial streams and the microbiota of the hyporheic soils (wetted soil zone) underlying and adjacent to those mats. It is hypothesized that the mats are important sources of organic carbon and fixed nitrogen for the soil communities of the hyporheic zone, and release dissolved organic carbon (DOC) and nitrogen (DON) that serves the entire Dry Valley ecosystem. Field efforts will entail both observational and experimental components. Direct comparisons will be made between the mats and microbial populations underlying naturally rehydrated and desiccated mat areas, and between mat areas in the melt streams of the Adams and Miers Glaciers in Miers Valley. Both physiological and phylogenetic indices of the soil microbiota will be examined. Observations will include estimates of rates of mat carbon and nitrogen fixation, soil respiration and leucine and thymidine uptake (as measures of protein \u0026 DNA synthesis, respectively) by soil bacteria, bacterial densities and their molecular ecology. Experimental manipulations will include experimental re-wetting of soils and observations of the time course of response of the microbial community. The research will integrate modern molecular genetic approaches (ARISA-DNA fingerprinting and ultra deep 16S rDNA microbial phylogenetic analysis) with geochemistry to study the diversity, ecology, and function of microbial communities that thrive in these extreme environments. The broader impacts of the project include research and educational opportunities for graduate students and a postdoctoral associate. The P.I.s will involve undergraduates as work-study students and in REU programs, and will participate in educational and outreach programs.", "east": 163.0, "geometry": "POINT(163 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cary, Stephen", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.5, "title": "Collaborative Research: Biogeochemistry of Cyanobactrial Mats and Hyporheic Zone Microbes in McMurdo Dry Valley Glacial Meltwater Streams", "uid": "p0000476", "west": 163.0}, {"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": null, "bounds_geometry": null, "dataset_titles": "Depths to Ice-cemented Soils in High-elevation Quartermain Mountains, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "609529", "doi": "10.7265/N5VX0DFJ", "repository": "USAP-DC", "science_program": null, "title": "Depths to Ice-cemented Soils in High-elevation Quartermain Mountains, Dry Valleys, Antarctica", "url": "http://www.usap-dc.org/view/dataset/609529"}], "date_created": "Mon, 18 Mar 2013 00:00:00 GMT", "description": null, "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Critical Zone; Dry Valleys; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Permafrost; Soil", "locations": "Dry Valleys; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Marinova, Margarita M.; McKay, Christopher P.", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": null, "uid": null, "west": null}, {"awards": "1241487 Adams, Byron", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 06 Jul 2012 00:00:00 GMT", "description": "This award will support the participation of US scientists in an international planning workshop devoted to discussions of how to best facilitate and coordinate international efforts for terrestrial system studies at the McMurdo Dry Valleys of Antarctica. To date, various aspects of the different Dry Valley landscape features (lakes, soils, glaciers, streams) and their biota have been studied most intensively by US and New Zealand scientists, but these efforts could significantly improve their explanatory power if they were coordinated so as to reduce redundancy, decrease environmental degradation and, most importantly, produce comparable datasets. Additionally, many of the present environmental management programs are based on the past baseline composition and location of biotic communities. As these communities become rearranged across the valleys in the future there is interest in assessing whether today\u0027s management plans are adequate. To efficiently move these research programs forward for the McMurdo Dry Valleys requires a coordinated, interdisciplinary, long-term data monitoring and observation network. \u003cbr/\u003e\u003cbr/\u003eThe ultimate objectives of the workshop are to: i) identify the optimal, complementary suites of measurements required to assess and address key processes associated with environmental change in Dry Valley ecosystems; ii) develop standards and protocols for gathering the most critical biotic and abiotic measurements associated with the key processes driving environmental change; iii) generate a draft data coordination and development plan that will maximize the utility of these data; iv) assess the effectiveness of current McMurdo Dry Valley ASMA (Antarctic Special Management Area) environmental protection guidelines.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Integrated System Science", "paleo_time": null, "persons": "Adams, Byron", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "A Planning Workshop for a McMurdo Dry Valleys Terrestrial Observation Network", "uid": "p0000126", "west": null}, {"awards": "0636218 Gillies, John", "bounds_geometry": "POLYGON((161.85075 -77.37241,161.990843 -77.37241,162.130936 -77.37241,162.271029 -77.37241,162.411122 -77.37241,162.551215 -77.37241,162.691308 -77.37241,162.831401 -77.37241,162.971494 -77.37241,163.111587 -77.37241,163.25168 -77.37241,163.25168 -77.395964,163.25168 -77.419518,163.25168 -77.443072,163.25168 -77.466626,163.25168 -77.49018000000001,163.25168 -77.513734,163.25168 -77.537288,163.25168 -77.56084200000001,163.25168 -77.584396,163.25168 -77.60795,163.111587 -77.60795,162.971494 -77.60795,162.831401 -77.60795,162.691308 -77.60795,162.551215 -77.60795,162.411122 -77.60795,162.271029 -77.60795,162.130936 -77.60795,161.990843 -77.60795,161.85075 -77.60795,161.85075 -77.584396,161.85075 -77.56084200000001,161.85075 -77.537288,161.85075 -77.513734,161.85075 -77.49018000000001,161.85075 -77.466626,161.85075 -77.443072,161.85075 -77.419518,161.85075 -77.395964,161.85075 -77.37241))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 05 Jun 2012 00:00:00 GMT", "description": "This project characterizes wind-driven sediment transport in the McMurdo Dry Valleys of \u003cbr/\u003eAntarctica during both winter and summer periods. Wind is the primary sculptor of\u003cbr/\u003eterrain in this region and winter measurements, which have never been undertaken, are\u003cbr/\u003eessential for determining the frequency and magnitude of transport events. The projects\u003cbr/\u003egoal is to determine if the existing landforms represent relics from past climate regimes\u003cbr/\u003eor contemporary processes. The project involves two major activities: (1) dynamic and\u003cbr/\u003etime-integrated measurements of sand transport to characterize the seasonal behavior,\u003cbr/\u003efrequency, and magnitude at four sites and (2) detailed surveying of an unusual\u003cbr/\u003ewind-formed surface feature, the gravel megaripples found in the Wright Valley. In\u003cbr/\u003eaddition to interpreting Dry Valleys geomorphology, these data will provide a more\u003cbr/\u003equantitative assessment of wind-aided distribution of nutrients, plants, and animals to\u003cbr/\u003eterrestrial and aquatic ecosystems throughout the Dry Valleys. This research will also\u003cbr/\u003eprovide quantitative information on the effects of extreme cold and low humidity on\u003cbr/\u003etransport thresholds and rates, which can be applied to cold desert environments of the\u003cbr/\u003eArctic, Antarctic, and Mars.", "east": 163.25168, "geometry": "POINT(162.551215 -77.49018)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -77.37241, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Gillies, John", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.60795, "title": "Dynamics of Aeolian Processes in the McMurdo Dry Valleys, Antarctica", "uid": "p0000739", "west": 161.85075}, {"awards": "9527571 Whillans, Ian", "bounds_geometry": "POLYGON((158.25 -76.66667,158.325 -76.66667,158.4 -76.66667,158.475 -76.66667,158.55 -76.66667,158.625 -76.66667,158.7 -76.66667,158.775 -76.66667,158.85 -76.66667,158.925 -76.66667,159 -76.66667,159 -76.683336,159 -76.700002,159 -76.716668,159 -76.733334,159 -76.75,159 -76.766666,159 -76.783332,159 -76.799998,159 -76.816664,159 -76.83333,158.925 -76.83333,158.85 -76.83333,158.775 -76.83333,158.7 -76.83333,158.625 -76.83333,158.55 -76.83333,158.475 -76.83333,158.4 -76.83333,158.325 -76.83333,158.25 -76.83333,158.25 -76.816664,158.25 -76.799998,158.25 -76.783332,158.25 -76.766666,158.25 -76.75,158.25 -76.733334,158.25 -76.716668,158.25 -76.700002,158.25 -76.683336,158.25 -76.66667))", "dataset_titles": "GPS Ice Flow Measurements, Allan Hills, Antarctica", "datasets": [{"dataset_uid": "609507", "doi": "10.7265/N5NS0RSX", "keywords": "Allan Hills; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity", "people": "Spikes, Vandy Blue; Hamilton, Gordon S.; Spaulding, Nicole; Kurbatov, Andrei V.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "GPS Ice Flow Measurements, Allan Hills, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609507"}], "date_created": "Tue, 20 Dec 2011 00:00:00 GMT", "description": "Whillans, Wilson, Goad OPP 9527571 Abstract This award supports a project to initiate Global Positioning System (GPS) measurements for rock motions in South Victoria Land and vicinity. The results will be used to test some of the leading models for ice-sheet change and tectonism, in particular, whether the continent is rebounding due to reduced ice load from East or West Antarctica and whether there is tectonic motion due to Terror Rift or uplift of the Transantarctic Mountains. A modest program to measure ice motion will be conducted as well. The motive is to test models for ice flow in the Allan Hills meteorite concentration region and to determine whether small glaciers in the Dry Valleys are thickening or thinning. Monuments will be set into rock and ice and GPS receivers used to determine their locations. Repeats in later years will determine motion. Field activities will involve close cooperation with the USGS.", "east": 159.0, "geometry": "POINT(158.625 -76.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; LABORATORY; Not provided; Ice Movement; GPS Data; Vertical Motions; GPS; FIELD INVESTIGATION", "locations": null, "north": -76.66667, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Whillans, Ian; Spaulding, Nicole; Hamilton, Gordon S.; Spikes, Vandy Blue; Kurbatov, Andrei V.", "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": "Allan Hills", "south": -76.83333, "title": "GPS Measurements of Rock and Ice Motions in South Victoria Land", "uid": "p0000523", "west": 158.25}, {"awards": "1048343 Warny, Sophie", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Palynological samples list", "datasets": [{"dataset_uid": "601151", "doi": "10.15784/601151", "keywords": "Antarctica; Glaciology; Marine Geoscience; Marine Sediments; Microscope; Microscopy; Paleoclimate; Pollen", "people": "Warny, Sophie", "repository": "USAP-DC", "science_program": null, "title": "Palynological samples list", "url": "https://www.usap-dc.org/view/dataset/601151"}], "date_created": "Sat, 10 Dec 2011 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PI proposes a high-resolution paleoenvironmental study of pollen, spore, fresh-water algae, and dinoflagellate cyst assemblages to investigate the palynological record of sudden warming events in the Antarctic as recorded by the ANDRILL SMS drill core and terrestrial sections. These data will be used to derive causal mechanisms for these rapid climate events. Terrestrial samples will be obtained at various altitudes in the Dry Valleys region. The pollen and spores will provide data on atmospheric conditions, while the algae will provide data on sea-surface conditions. These data will help identify the triggers for sudden climatic shifts. If they are caused by changes in oceanic currents, a signal will be visible in the dinocyst assemblages first as currents influence their distribution. Conversely, if these shifts are triggered by atmospheric factors, then the shifts will first affect plants and be visible in the pollen record.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe PI proposes a suite of activities to bring field-based climate change research to a broader audience. The PI will advise a diverse group of students and educators. The palynological data collected as part of this research will be utilized, in part, to develop new lectures on Antarctic palynology and these new lectures will be made available via a collaboration with the LSU HHMI program. In addition, the PI will direct three Louisiana middle-school teachers as they pursue a Masters of Natural Science for science educators. These teachers will help the PI develop a professional development program for science teachers. Community-based activities will be organized to raise science awareness and alert students and the public of opportunities in science.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "MICROFOSSILS; NOT APPLICABLE", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Warny, Sophie", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WISSARD; ANDRILL; SHALDRIL", "south": -75.0, "title": "CAREER: Deciphering Antarctic Climate Variability during the Temperate/Polar Transition and Improving Climate Change Literacy in Louisiana through a Companion Outreach Program", "uid": "p0000311", "west": -180.0}, {"awards": "0840979 Adams, Byron; 0840705 Wall, Diana", "bounds_geometry": "POLYGON((165.35155 -83.71592,166.143133 -83.71592,166.934716 -83.71592,167.726299 -83.71592,168.517882 -83.71592,169.309465 -83.71592,170.101048 -83.71592,170.892631 -83.71592,171.684214 -83.71592,172.475797 -83.71592,173.26738 -83.71592,173.26738 -83.894053,173.26738 -84.072186,173.26738 -84.250319,173.26738 -84.428452,173.26738 -84.606585,173.26738 -84.784718,173.26738 -84.962851,173.26738 -85.140984,173.26738 -85.319117,173.26738 -85.49725,172.475797 -85.49725,171.684214 -85.49725,170.892631 -85.49725,170.101048 -85.49725,169.309465 -85.49725,168.517882 -85.49725,167.726299 -85.49725,166.934716 -85.49725,166.143133 -85.49725,165.35155 -85.49725,165.35155 -85.319117,165.35155 -85.140984,165.35155 -84.962851,165.35155 -84.784718,165.35155 -84.606585,165.35155 -84.428452,165.35155 -84.250319,165.35155 -84.072186,165.35155 -83.894053,165.35155 -83.71592))", "dataset_titles": "Genetic Sequences: JN819273 tardsubmission.sqn 354_18S6 JN819274 tardsubmission.sqn 354_ITS JN819275 tardsubmission.sqn 553_18S5_and_18S6 JN819276 tardsubmission.sqn 556_18S6; McMurdo Dry Valleys Long-Term Ecological Research", "datasets": [{"dataset_uid": "000217", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Genetic Sequences: JN819273 tardsubmission.sqn 354_18S6 JN819274 tardsubmission.sqn 354_ITS JN819275 tardsubmission.sqn 553_18S5_and_18S6 JN819276 tardsubmission.sqn 556_18S6", "url": "http://www.ncbi.nlm.nih.gov/genbank/"}, {"dataset_uid": "000157", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys Long-Term Ecological Research", "url": "http://www.mcmlter.org/"}], "date_created": "Mon, 03 Oct 2011 00:00:00 GMT", "description": "Ice sheet models of the Last Glacial Maximum, and previous glaciation events in the Miocene, suggest that current low altitude, ice-free surfaces in Antarctica were completely covered with ice. If so, the terrestrial biota of Antarctica today would result from recolonization events after each glacial maximum. However, there is emerging evidence that much of the terrestrial Antarctic biota are of ancient origin and have somehow survived these glaciation events. The Transantarctic Mountains TRANsition Zone (TAM-TRANZ) plays a pivotal role in understanding the evolution and biogeographic history of today\u0027s Antarctic terrestrial biota, primarily because it contains numerous inland areas that could have served as refugia during glacial maxima. Due to its remote location, the TAM-TRANZ has not been systematically surveyed for animal biodiversity. Although an exhaustive survey of the region requires a multi-discipline, multi-year and multi-region effort, the research herein combines ecological, evolutionary and geophysical expertise to conduct an exploratory investigation of the extreme southern limits of biotic communities. The project will examine the historical geophysical requirements for the colonization and maintenance of functional ecosystems by multicellular organisms, and the feasibility and desirability to implement more systematic biogeographic studies in the future. Broader impacts include graduate and undergraduate student ownership of important subprojects that will provide research, presentation and publication opportunities. The investigators also will contribute to ongoing public education efforts through relationships with K-12 teachers and administrators in the public school districts where the project personnel reside. Finally, the project is leveraged by opportunistic collaboration with scientists associated with Antarctica New Zealand.", "east": 173.26738, "geometry": "POINT(169.309465 -84.606585)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -83.71592, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Adams, Byron; Wall, Diana", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "LTER; NCBI GenBank", "science_programs": "LTER", "south": -85.49725, "title": "Collaborative Research: Limits and Drivers of Metazoan Distributions in the Transantarctic Mountains", "uid": "p0000517", "west": 165.35155}, {"awards": "0538033 Panter, Kurt", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 14 Sep 2011 00:00:00 GMT", "description": "This project studies glaciovolcanic deposits at Minna Bluff in the western Ross Embayment of Antarctica. Its goal is to determine the history of the Ross Ice Shelf, which is fed by the major ice sheets from both East and West Antarctica. Apart from determining how these ice sheets waxed and waned during a period of dynamic climate change, glaciovolcanic sequences may constrain ice sheet parameters that are critical to numerical models such as thickness, hydrology, and basal thermal regime. This three-year study would map, analyze, and determine the age of key units using 40Ar/39Ar dating. Pilot studies would also be conducted for 36Cl dating of glacial deposits and stable isotope evaluations of alteration. The project offers a complementary record of Ross Ice Shelf behavior to that sampled by ANDRILL. It also improves the general record of McMurdo area volcanostratigraphy, which is important to interpreting landforms, glacial deposits, and ancient ice found in the Dry Valleys.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this project include improving society\u0027s understanding of global climate change, sea level rise, and graduate and undergraduate student education. Outreach efforts include educational programs for public schools and community groups, exhibits for a local science museum, and a project website.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Panter, Kurt", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Proposal: Late Cenozoic Volcanism and Glaciation at Minna Bluff, Antarctica: Implications for Antarctic Cryosphere History", "uid": "p0000252", "west": null}, {"awards": "0636731 Bender, Michael; 0636705 Marchant, David", "bounds_geometry": "POLYGON((160.48705 -77.84513,160.501913 -77.84513,160.516776 -77.84513,160.531639 -77.84513,160.546502 -77.84513,160.561365 -77.84513,160.576228 -77.84513,160.591091 -77.84513,160.605954 -77.84513,160.620817 -77.84513,160.63568 -77.84513,160.63568 -77.8515624,160.63568 -77.8579948,160.63568 -77.8644272,160.63568 -77.8708596,160.63568 -77.877292,160.63568 -77.8837244,160.63568 -77.8901568,160.63568 -77.8965892,160.63568 -77.9030216,160.63568 -77.909454,160.620817 -77.909454,160.605954 -77.909454,160.591091 -77.909454,160.576228 -77.909454,160.561365 -77.909454,160.546502 -77.909454,160.531639 -77.909454,160.516776 -77.909454,160.501913 -77.909454,160.48705 -77.909454,160.48705 -77.9030216,160.48705 -77.8965892,160.48705 -77.8901568,160.48705 -77.8837244,160.48705 -77.877292,160.48705 -77.8708596,160.48705 -77.8644272,160.48705 -77.8579948,160.48705 -77.8515624,160.48705 -77.84513))", "dataset_titles": "Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica; Measurements of Trapped Air from Mullins Valley, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "600069", "doi": "10.15784/600069", "keywords": "Antarctica; Dry Valleys; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope Record; Lake Vostok; Paleoclimate", "people": "Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600069"}, {"dataset_uid": "609597", "doi": "10.7265/N50R9MBM", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Dry Valleys; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Radar Interferometer", "people": "Yau, Audrey M.; Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Measurements of Trapped Air from Mullins Valley, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609597"}], "date_created": "Thu, 03 Feb 2011 00:00:00 GMT", "description": "This project studies ancient ice buried in the Dry Valleys of Antarctica. The ice, which may approach ten million years in age, will be dated using argon and uranium radioisotope techniques. High-risk work, if successful it will offer the first and perhaps only samples of the Earth\u0027s atmosphere from millions of years in the past. These samples could offer critically important tests of paleoclimate records and proxies, as well as a glimpse into the characteristics of a past world much like the predicted future, warmer Earth. The broader impacts are graduate student education, and potentially contributing to society\u0027s understanding of global climate change and sea level rise.", "east": 160.63568, "geometry": "POINT(160.561365 -77.877292)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Elemental Ratios; Oxygen Isotope; Not provided; Nitrogen Isotopes; LABORATORY; Argon Isotopes; FIELD INVESTIGATION", "locations": null, "north": -77.84513, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Bender, Michael; Yau, Audrey M.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.909454, "title": "Collaborative Research: Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica", "uid": "p0000039", "west": 160.48705}, {"awards": "0631494 Priscu, John; 0631659 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": "GenBank (NCBI) 18S rRNA genes: GU969060 to GU969102, rbcL genes: GU132860 to GU132939; McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) Program", "datasets": [{"dataset_uid": "000126", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "GenBank (NCBI) 18S rRNA genes: GU969060 to GU969102, rbcL genes: GU132860 to GU132939", "url": "http://www.ncbi.nlm.nih.gov/genbank/"}, {"dataset_uid": "000125", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) Program", "url": "http://www.mcmlter.org/"}], "date_created": "Fri, 08 Oct 2010 00:00:00 GMT", "description": "Data collected on the permanently ice-covered lakes of the McMurdo Dry Valleys (MCM) during the late 1950\u0027s as part of the International Geophysical Year (IGY) showed that they were the only year round liquid water environments on the continent. Organisms in the lakes must possess novel physiological strategies that allow them to survive at low temperature and under extended darkness. Subsequent research has now shown that most organisms in the lakes are not just \"surviving the extremes\" but are actively feeding, growing and reproducing. However, nearly all research on the MCM lakes is restricted to the austral spring and summer when logistical support is provided. The unique aspects of physiological adaptation and metabolic function during the permanently cold and prolonged darkness of the Antarctic winter remain unknown. As part of the \"International Polar Year 2007-2008\" (IPY), the proposed research will study lakes within the Taylor Valley during the transition to polar night to test the overarching hypothesis that the onset of darkness induces a cascade of physiological changes that alters the functional role of autotrophic and heterotrophic microplankton within the lakes. This overarching theme will be addressed through an interdisciplinary study of selected biological components of the lake ecosystems using genomic and physiological tools to understand not only how individual organisms survive, but how they control ecosystem function during this seasonal transition. \u003cbr/\u003e\u003cbr/\u003eThis project is directly relevant to IPY objectives as it addresses a major identified theme (Adaptations to Life in Extreme Cold and Prolonged Darkness) with an international (UK, NZ),\u003cbr/\u003emultidisciplinary team. The research has substantial broader impacts, as it will add to the body of long-term data accumulated by the MCM LTER and MCM Microbial Observatory projects in a synergistic manner; and it will include three undergraduates, a graduate student and two young female investigators. The project is linked to a highly visible education, outreach and human diversity programs supported by the McMurdo LTER, and initiates new outreach programs, including the Passport to Knowledge program.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Morgan-Kiss, Rachael; Priscu, John; Mikucki, Jill", "platforms": "Not provided", "repo": "NCBI GenBank", "repositories": "LTER; NCBI GenBank", "science_programs": "LTER", "south": -90.0, "title": "Collaborative Research: IPY- Plankton Dynamics in the McMurdo Dry Valley Lakes During the Transition to Polar Night", "uid": "p0000525", "west": -180.0}, {"awards": "0086645 Fountain, Andrew", "bounds_geometry": "POLYGON((161.04 -77.3,161.239 -77.3,161.438 -77.3,161.637 -77.3,161.836 -77.3,162.035 -77.3,162.234 -77.3,162.433 -77.3,162.632 -77.3,162.831 -77.3,163.03 -77.3,163.03 -77.378,163.03 -77.456,163.03 -77.534,163.03 -77.612,163.03 -77.69,163.03 -77.768,163.03 -77.846,163.03 -77.924,163.03 -78.002,163.03 -78.08,162.831 -78.08,162.632 -78.08,162.433 -78.08,162.234 -78.08,162.035 -78.08,161.836 -78.08,161.637 -78.08,161.438 -78.08,161.239 -78.08,161.04 -78.08,161.04 -78.002,161.04 -77.924,161.04 -77.846,161.04 -77.768,161.04 -77.69,161.04 -77.612,161.04 -77.534,161.04 -77.456,161.04 -77.378,161.04 -77.3))", "dataset_titles": "McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) Core Glacier Mass Balance Data, Antarctica", "datasets": [{"dataset_uid": "609421", "doi": "", "keywords": "Antarctica; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; LTER; LTER Mcmurdo Dry Valleys", "people": "Fountain, Andrew; Langevin, Paul; Lyons, W. Berry; Nylen, Thomas; Basagic, Hassan", "repository": "USAP-DC", "science_program": null, "title": "McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) Core Glacier Mass Balance Data, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609421"}], "date_created": "Mon, 31 Aug 2009 00:00:00 GMT", "description": "0086645\u003cbr/\u003eFountain\u003cbr/\u003e\u003cbr/\u003eThis award supports a Small Grant for Exploratory Research (SGER) to study glaciological change in the McMurdo Dry Valleys, Antarctica under the category of \"application of new expertise or new approaches to established research topics\". The purpose of the project is to assess the application of classified imagery to the study of the magnitude and rate of change of glacier extent and lake area as an indicator of climate change. Because the rate of change of both glacier extent and lake area is small compared to the resolution of unclassified imagery, the increased resolution of classified imagery is clearly needed. Access to classified imagery with 1 meter or better resolution will provide a baseline measurement against which future changes can be compared. Maximum use will be made of archived imagery but if necessary, one request will be made for new imagery to supplement the existing archive. This work will support on-going field measurements which are part of the Long-Term Ecological Research (LTER) site in the McMurdo Dry Valleys but which are limited by logistic constraints to only a few measurements during limited times of the year. If successful, the information gained in this project will enable researchers to better direct their efforts to identify the important physical processes controlling the changes in the valleys. The information acquired in conducting this project will be made available to the public, using appropriate security procedures to declassify the data. The \"exploratory\" and \"high risk\" nature of the proposed work and its \"potential\" to make an important \"impact\" on the field of Antarctic glacier studies are all reasons that this work is appropriate to support as an SGER.", "east": 163.03, "geometry": "POINT(162.035 -77.69)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SNOW DENSITY CUTTER", "is_usap_dc": true, "keywords": "Glacier Surface; Antarctic; LABORATORY; Byrd Polar Research Center; FIELD INVESTIGATION; FIELD SURVEYS; Antarctica; Not provided; Glacier; Mass Balance; Snow Density; Ice Core; Taylor Glacier", "locations": "Antarctic; Antarctica; Taylor Glacier", "north": -77.3, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Nylen, Thomas; Basagic, Hassan; Langevin, Paul; Lyons, W. 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These deposits are particularly exciting because they preserve flora and fauna over seven million years in age that represent the last vestiges of ecosystems that dominated this area before formation of the modern East Antarctic ice sheet. Their unique nature offers a chance to bridge modern and ancient ecology. Formed along the margin of ancient alpine glaciers, these deposits contain layers of silt, clay, and volcanic ash; as well as freeze-dried remnants of mosses, insects, and diatoms. Geological and biological analyses provide a view of the ecological and environmental conditions during mid-to-late Miocene--seven to seventeen million years ago--which spans the critical period when the East Antarctic ice sheet transitioned to its present stable form. The results place the modern lakes of the Dry Valleys into a long-term evolutionary framework, and allow for correlation and dating comparisons with other fossil-rich deposits from the Transantarctic Mountains. Chemical fingerprinting and dating of volcanic glass shards will also help date fossil- and ash-bearing horizons in nearby marine cores, such as those to be collected under the ANDRILL program. \u003cbr/\u003e\u003cbr/\u003eThe broader impacts are education at the postdoctoral, graduate, and undergraduate levels; and collaboration between a research institution and primarily undergraduate institution. The work also improves our understanding of global climate change during a critical period in the Earth\u0027s history.", "east": 164.5, "geometry": "POINT(162.25 -77.5)", "instruments": null, "is_usap_dc": false, "keywords": "Paleoclimate; Not provided; Lacustrine; Tundra; Middle Miocene; McMurdo Dry Valleys; Vegetation; Fossil; Antarctica", "locations": "Antarctica; McMurdo Dry Valleys", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Marchant, David", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.5, "title": "Collaborative Research: Deducing Late Neogene Antarctic Climate from Fossil-Rich Lacustrine Sediments in the Dry Valleys", "uid": "p0000186", "west": 160.0}, {"awards": "0739700 Marchant, David; 0739693 Ashworth, Allan", "bounds_geometry": "POLYGON((160 -77,160.2 -77,160.4 -77,160.6 -77,160.8 -77,161 -77,161.2 -77,161.4 -77,161.6 -77,161.8 -77,162 -77,162 -77.1,162 -77.2,162 -77.3,162 -77.4,162 -77.5,162 -77.6,162 -77.7,162 -77.8,162 -77.9,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -78,161 -78,160.8 -78,160.6 -78,160.4 -78,160.2 -78,160 -78,160 -77.9,160 -77.8,160 -77.7,160 -77.6,160 -77.5,160 -77.4,160 -77.3,160 -77.2,160 -77.1,160 -77))", "dataset_titles": "Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "datasets": [{"dataset_uid": "600081", "doi": "10.15784/600081", "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; GPS; Solid Earth", "people": "Ashworth, Allan; Lewis, Adam", "repository": "USAP-DC", "science_program": null, "title": "Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/600081"}], "date_created": "Mon, 22 Jun 2009 00:00:00 GMT", "description": "This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia.\u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica\u0027s ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise.", "east": 162.0, "geometry": "POINT(161 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; Antarctica; Vegetation; Paleoclimate; Middle Miocene; Tundra; Bu/es Data Repository; McMurdo Dry Valleys; Lacustrine; Fossil", "locations": "Antarctica; McMurdo Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Ashworth, Allan; Lewis, Adam", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Integrating Geomorphological and Paleoecological Studies to Reconstruct Neogene Environments of the Transantarctic Mountains", "uid": "p0000188", "west": 160.0}, {"awards": "0636269 Harpp, Karen", "bounds_geometry": "POLYGON((161.55 -77.50314,161.5883 -77.50314,161.6266 -77.50314,161.66490000000002 -77.50314,161.7032 -77.50314,161.7415 -77.50314,161.7798 -77.50314,161.8181 -77.50314,161.8564 -77.50314,161.8947 -77.50314,161.933 -77.50314,161.933 -77.507124,161.933 -77.51110800000001,161.933 -77.515092,161.933 -77.519076,161.933 -77.52306,161.933 -77.527044,161.933 -77.531028,161.933 -77.535012,161.933 -77.538996,161.933 -77.54298,161.8947 -77.54298,161.8564 -77.54298,161.8181 -77.54298,161.7798 -77.54298,161.7415 -77.54298,161.7032 -77.54298,161.66490000000002 -77.54298,161.6266 -77.54298,161.5883 -77.54298,161.55 -77.54298,161.55 -77.538996,161.55 -77.535012,161.55 -77.531028,161.55 -77.527044,161.55 -77.52306,161.55 -77.519076,161.55 -77.515092,161.55 -77.51110800000001,161.55 -77.507124,161.55 -77.50314))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 03 Jun 2009 00:00:00 GMT", "description": "This project is a field and laboratory based investigation of the Vanda dike swarm in the Dry Valleys of Antarctica. These dikes crosscut Cambro-Ordovician granitoid plutons produced during the Ross Orogeny, and mark the transition between the cessation of subduction and the onset of extensional magmatism. Many dying convergent plate margins convert to extensional magmatism, and the Dry Valleys provide a magnificent opportunity to examine the shallow roots of a plate that experienced this transition. Because of their exceptional exposure, bimodal felsic and mafic compositions, and complex field relations, the Vanda dikes have the potential to reveal insights into this important phase of Antarctic tectonic history. \u003cbr/\u003eThe broader impacts include collaboration between a primarily undergraduate and two research institutions, and support for undergraduate participation in an exciting, field-based research project.", "east": 161.933, "geometry": "POINT(161.7415 -77.52306)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.50314, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Harpp, Karen", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.54298, "title": "Collaborative Research, RUI: The Transition from Subduction to Extensional Magmatism in the Dry Valleys of Antarctica", "uid": "p0000546", "west": 161.55}, {"awards": "0739702 Head, James", "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, 14 May 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThis project uses Aster and Hyperion remote sensing data combined with field observations and laboratory analysis to map soils in the McMurdo Dry Valleys of Antarctica. The goal is to use mineral abundances, compositions, and spatial heterogeneities to investigate the connections between microclimate and surface characteristics. The valleys are one of the most unique landscapes on earth. The outcomes will be relevant to understanding their geologic, biologic, and climactic history, and offer insight into the Martian landscape. The main broader impacts are graduate education and curriculum development involving K12 teachers.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wyatt, Michael", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Orbital Spectral Mapping of Surface Compositions in the Antarctic Dry Valleys: Regional Distributions of Secondary Mineral-Phases as Climate Indicators", "uid": "p0000549", "west": -180.0}, {"awards": "0739452 Mukhopadhyay, Sujoy", "bounds_geometry": "POLYGON((161 -76,161.2 -76,161.4 -76,161.6 -76,161.8 -76,162 -76,162.2 -76,162.4 -76,162.6 -76,162.8 -76,163 -76,163 -76.2,163 -76.4,163 -76.6,163 -76.8,163 -77,163 -77.2,163 -77.4,163 -77.6,163 -77.8,163 -78,162.8 -78,162.6 -78,162.4 -78,162.2 -78,162 -78,161.8 -78,161.6 -78,161.4 -78,161.2 -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": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "datasets": [{"dataset_uid": "600074", "doi": "10.15784/600074", "keywords": "Antarctica; Cosmogenic Dating; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Paleoclimate; Sample/collection Description; Sample/Collection Description; Solid Earth", "people": "Mukhopadhyay, Sujoy", "repository": "USAP-DC", "science_program": null, "title": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "url": "https://www.usap-dc.org/view/dataset/600074"}], "date_created": "Mon, 30 Mar 2009 00:00:00 GMT", "description": "This project seeks to answer a simple question: how old are potholes and related geomorphic features found in the uplands of the McMurdo Dry Valleys, Antarctica? Some research suggests that they are over ten million years old and date the growth of the East Antarctic Ice Sheet, the world?s largest. However, some evidence suggests that these are young, erosional features that continuing to evolve to this day. This project uses cosmogenic nuclide dating to determine the age of the pothole floors. The results are important for determining the ice sheet?s history and interpreting the O-isotope record from the marine sediment cores, key records of global climate. Broader impacts include K12 outreach and incorporation of outcomes into university courses.", "east": 163.0, "geometry": "POINT(162 -77)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Mukhopadhyay, Sujoy", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Landform Evolution in the Dry Valleys and its implications for Miocene-Pliocene Climate Change in Antarctica", "uid": "p0000461", "west": 161.0}, {"awards": "0636629 Kurz, Mark", "bounds_geometry": "POLYGON((160.7 -77.8,161.06 -77.8,161.42 -77.8,161.78 -77.8,162.14 -77.8,162.5 -77.8,162.86 -77.8,163.22 -77.8,163.58 -77.8,163.94 -77.8,164.3 -77.8,164.3 -77.86,164.3 -77.92,164.3 -77.98,164.3 -78.04,164.3 -78.1,164.3 -78.16,164.3 -78.22,164.3 -78.28,164.3 -78.34,164.3 -78.4,163.94 -78.4,163.58 -78.4,163.22 -78.4,162.86 -78.4,162.5 -78.4,162.14 -78.4,161.78 -78.4,161.42 -78.4,161.06 -78.4,160.7 -78.4,160.7 -78.34,160.7 -78.28,160.7 -78.22,160.7 -78.16,160.7 -78.1,160.7 -78.04,160.7 -77.98,160.7 -77.92,160.7 -77.86,160.7 -77.8))", "dataset_titles": "Periglacial Landscape Evolution in Antarctic Lava Flows and Glacial Tills", "datasets": [{"dataset_uid": "600066", "doi": "10.15784/600066", "keywords": "Antarctica; Cosmogenic Radionuclides; Dry Valleys; Geology/Geophysics - Other; Glaciology; LIDAR; Navigation; Sample/collection Description; Sample/Collection Description", "people": "Soule, S. Adam; Kurz, Mark D.", "repository": "USAP-DC", "science_program": null, "title": "Periglacial Landscape Evolution in Antarctic Lava Flows and Glacial Tills", "url": "https://www.usap-dc.org/view/dataset/600066"}], "date_created": "Sun, 01 Feb 2009 00:00:00 GMT", "description": "This project uses cosmogenic nuclide dating and LIDAR studies of surface roughness to understand weathering and landscape evolution in the Dry Valleys of Antarctica. The work focuses on two processes: cryoturbation of frozen soils and the development of patterned, frozen ground on ancient lava flows. The approach includes innovative uses of He3 profiling. Results will also be applied to understanding the glacial history of the Dry Valleys. There are potential applications to understanding the history of the East Antarctic Ice Sheet and the formation of Martian landscapes. The broader impacts include graduate student education. As well, the work may contribute to our understanding of the history of the Antarctic ice sheets, which is important to modeling their behavior during global climate change.", "east": 164.3, "geometry": "POINT(162.5 -78.1)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION", "locations": null, "north": -77.8, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soule, Samuel; Kurz, Mark D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.4, "title": "Periglacial Landscape Evolution in Antarctic Lava Flows and Glacial Tills", "uid": "p0000559", "west": 160.7}, {"awards": "0230276 Ward, Bess", "bounds_geometry": "POLYGON((162 -77.2,162.16 -77.2,162.32 -77.2,162.48 -77.2,162.64 -77.2,162.8 -77.2,162.96 -77.2,163.12 -77.2,163.28 -77.2,163.44 -77.2,163.6 -77.2,163.6 -77.26,163.6 -77.32,163.6 -77.38,163.6 -77.44,163.6 -77.5,163.6 -77.56,163.6 -77.62,163.6 -77.68,163.6 -77.74,163.6 -77.8,163.44 -77.8,163.28 -77.8,163.12 -77.8,162.96 -77.8,162.8 -77.8,162.64 -77.8,162.48 -77.8,162.32 -77.8,162.16 -77.8,162 -77.8,162 -77.74,162 -77.68,162 -77.62,162 -77.56,162 -77.5,162 -77.44,162 -77.38,162 -77.32,162 -77.26,162 -77.2))", "dataset_titles": "What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "datasets": [{"dataset_uid": "600033", "doi": "10.15784/600033", "keywords": "Antarctica; Biota; CTD Data; Dry Valleys; Lake Bonney; Lake Vanda; Microbiology; Taylor Valley", "people": "Ward, Bess", "repository": "USAP-DC", "science_program": null, "title": "What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "url": "https://www.usap-dc.org/view/dataset/600033"}], "date_created": "Sun, 18 Jan 2009 00:00:00 GMT", "description": "Denitrification is the main process by which fixed nitrogen is lost from ecosystems and the regulation of this process may directly affect primary production and carbon cycling over short and long time scales. Previous investigations of the role of bioactive metals in regulating denitrification in bacteria from permanently ice-covered Lake Bonney in the Taylor Valley of East Antarctica indicated that denitrifying bacteria can be negatively affected by metals such as copper, iron, cadmium, lead, chromium, nickel, silver and zinc; and that there is a distinct difference in denitrifying activity between the east and west lobes of the lake. Low iron concentrations were found to exacerbate the potential toxicity of the other metals, while silver has the potential to specifically inhibit denitrification because of its ability to interfere with copper binding in redox proteins, such as nitrite reductase and nitrous oxide reductase. High silver concentrations might prevent the functioning of nitrous oxide reductase in the same way that simple copper limitation does, thereby causing the buildup of nitrous oxide and resulting in a nonfunctional nitrogen cycle. Other factors, such as oxygen concentration, are likely also to affect bacterial activity in Lake Bonney. This project will investigate silver toxicity, general metal toxicity and oxygen concentration to determine their effect on denitrification in the lake by using a suite of \"sentinel\" strains of denitrifying bacteria (isolated from the lake) incubated in Lake Bonney water and subjected to various treatments. The physiological responses of these strains to changes in metal and oxygen concentration will be quantified by flow cytometric detection of single cell molecular probes whose sensitivity and interpretation have been optimized for the sentinel strains. Understanding the relationships between metals and denitrification is expected to enhance our understanding of not only Lake Bonney\u0027s unusual nitrogen cycle, but more generally, of the potential role of metals in the regulation of microbial nitrogen transformations.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this work include not only a better understanding of regional biogeochemistry and global perspectives on these processes; but also the training of graduate students and a substantial outreach effort for school children.", "east": 163.6, "geometry": "POINT(162.8 -77.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD", "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -77.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ward, Bess", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Collaborative Research: What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "uid": "p0000223", "west": 162.0}, {"awards": "0228052 Kreutz, Karl", "bounds_geometry": "POLYGON((161.0434 -77.3002,161.241645 -77.3002,161.43989 -77.3002,161.638135 -77.3002,161.83638 -77.3002,162.034625 -77.3002,162.23287 -77.3002,162.431115 -77.3002,162.62936 -77.3002,162.827605 -77.3002,163.02585 -77.3002,163.02585 -77.3784846,163.02585 -77.4567692,163.02585 -77.5350538,163.02585 -77.6133384,163.02585 -77.691623,163.02585 -77.7699076,163.02585 -77.8481922,163.02585 -77.9264768,163.02585 -78.0047614,163.02585 -78.083046,162.827605 -78.083046,162.62936 -78.083046,162.431115 -78.083046,162.23287 -78.083046,162.034625 -78.083046,161.83638 -78.083046,161.638135 -78.083046,161.43989 -78.083046,161.241645 -78.083046,161.0434 -78.083046,161.0434 -78.0047614,161.0434 -77.9264768,161.0434 -77.8481922,161.0434 -77.7699076,161.0434 -77.691623,161.0434 -77.6133384,161.0434 -77.5350538,161.0434 -77.4567692,161.0434 -77.3784846,161.0434 -77.3002))", "dataset_titles": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "609399", "doi": "10.7265/N5FF3Q92", "keywords": "Antarctica; Borehole Temperature; Chemistry:ice; Chemistry:Ice; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Mass Balance; Paleoclimate; Physical Properties", "people": "Mayewski, Paul A.; Kreutz, Karl", "repository": "USAP-DC", "science_program": null, "title": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609399"}], "date_created": "Tue, 21 Oct 2008 00:00:00 GMT", "description": "This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit of the project. We plan to collect intermediate-length ice cores (100-200m) at four sites along transects in Taylor Valley and Wright Valley, and analyze each core at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). A suite of statistical techniques will be applied to the multivariate glaciochemical dataset to identify chemical associations and to calibrate the time-series records with available instrumental data. Broader impacts of the project include: 1) contributions to several ongoing interdisciplinary Antarctic research programs; 2) graduate and undergraduate student involvement in field, laboratory, and data interpretation activities; 3) use of project data and ideas in several UMaine courses and outreach activities; and 4) data dissemination through peer-reviewed publications, UMaine and other paleoclimate data archive websites, and presentations at national and international meetings.", "east": 163.02585, "geometry": "POINT(162.034625 -77.691623)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MC-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e HUMIDITY SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "Holocene; Climate Research; AWS Climate Data; Paleoclimate; Climate Variation; Dry Valleys; Wright Valley; Little Ice Age; Stable Isotopes; Glaciochemical; Ice Core; FIELD INVESTIGATION; Enso; Antarctic Oscillation; Climate; GPS; El Nino-Southern Oscillation; LABORATORY; Not provided; Climate Change; Ice Core Records; Antarctica; Taylor Valley; FIELD SURVEYS; Variability", "locations": "Antarctica; Dry Valleys; Taylor Valley; Wright Valley", "north": -77.3002, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Arcone, Steven; Mayewski, Paul A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.083046, "title": "Dry Valleys Late Holocene Climate Variability", "uid": "p0000155", "west": 161.0434}, {"awards": "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": "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"}, {"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"}], "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": "USAP-DC", "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": "0124049 Berger, Glenn", "bounds_geometry": "POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 25 Aug 2008 00:00:00 GMT", "description": "0124049\u003cbr/\u003eBerger\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.", "east": 163.4, "geometry": "POINT(162.4 -77.6)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS", "is_usap_dc": false, "keywords": "Stratigraphy; Climate Variability; Shoreline Deposits; Dry Valleys; Antarctic Lake-level; Luminescence Geochronology; Grain Size; Paleoclimate; Antarctica; LABORATORY; Lake Cores", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Berger, Glenn; Hall, Brenda; Doran, Peter", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -77.7, "title": "Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change", "uid": "p0000219", "west": 161.4}, {"awards": "0648509 Sletten, Ronald", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Aug 2008 00:00:00 GMT", "description": "This Small Grant for Exploratory Research explores the use of magnesium isotopes in understanding the preservation of ice in soils from the Dry Valleys of Antarctica. With such little precipitation in the region, this ice should have completely sublimed away, nonetheless there is geologic evidence of ten-million-year-old ice in some areas. Its ubiquitous presence in Dry Valley\u0027s soils implies some form of recharge, seemingly incompatible with the low precipitation rates. This project studies the Mg-isotopes found in soluble salts and, by association, water transport. Magnesium isotopes undergo mass dependent fractionation during the volatilization and condensation, and thus offer the possibility to constrain both the water source and other processes by which ice is mobilized. The measurements require the high precision made possible only recently by development of the MC-ICPMS. The method will be applied to Mg-salts extracted from archived Antarctic soils, as well as cores recovered by the 1970s Dry Valley Drilling Project. \u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project would support a graduate student, who would learn cutting edge geochemical techniques while applying them to an exciting earth science question. This work is critical to understanding the environmental record offered by the Dry Valleys, including the deep ice records that may give seven-million year old samples of the earth\u0027s atmosphere. The work also has applications to understanding permafrost on Mars and interpreting recent rover observations.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sletten, Ronald S.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Small Grant Exploratory Research: The Application of Mg Isotopes as an Indictor for Water and Brine Migration into Dry Valley Permafrost", "uid": "p0000089", "west": null}, {"awards": "0233823 Fountain, Andrew; 0230338 Hallet, Bernard", "bounds_geometry": "POLYGON((162.132 -77.73,162.1495 -77.73,162.167 -77.73,162.1845 -77.73,162.202 -77.73,162.2195 -77.73,162.237 -77.73,162.2545 -77.73,162.272 -77.73,162.2895 -77.73,162.307 -77.73,162.307 -77.7303,162.307 -77.7306,162.307 -77.7309,162.307 -77.7312,162.307 -77.7315,162.307 -77.7318,162.307 -77.7321,162.307 -77.7324,162.307 -77.7327,162.307 -77.733,162.2895 -77.733,162.272 -77.733,162.2545 -77.733,162.237 -77.733,162.2195 -77.733,162.202 -77.733,162.1845 -77.733,162.167 -77.733,162.1495 -77.733,162.132 -77.733,162.132 -77.7327,162.132 -77.7324,162.132 -77.7321,162.132 -77.7318,162.132 -77.7315,162.132 -77.7312,162.132 -77.7309,162.132 -77.7306,162.132 -77.7303,162.132 -77.73))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 02 Jul 2008 00:00:00 GMT", "description": "This award supports a comprehensive study of land-based polar ice cliffs. Through field measurements, modeling, and remote sensing, the physics underlying the formation of ice cliffs at the margin of Taylor Glacier in the McMurdo Dry Valleys will be investigated. At three sites, measurements of ice deformation and temperature fields near the cliff face will be combined with existing energy balance data to quantify ice-cliff evolution over one full seasonal cycle. In addition, a small seismic network will monitor local \"ice quakes\" associated with calving events. Numerical modeling, validated by the field data, will enable determination of the sensitivity of ice cliff evolution to environmental variables. There are both local and global motivations for studying the ice cliffs of Taylor Glacier. On a global scale, this work will provide insight into the fundamental processes of calving and glacier terminus A better grasp of ice cliff processes will also improve boundary conditions required for predicting glaciers\u0027 response to climate change. Locally, the Taylor Glacier is an important component of the McMurdo Dry Valleys landscape and the results of this study will aid in defining ecologically-important sources of glacial meltwater and will lead to a better understanding of moraine formation at polar ice cliffs. This study will help launch the career of a female scientist, will support one graduate student, and provide experiential learning experiences for two undergraduates. The post-doctoral researcher will also use this research in the curriculum of a wilderness science experiential education program for high school girls.", "east": 162.307, "geometry": "POINT(162.2195 -77.7315)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMOCOUPLES \u003e THERMOCOUPLES; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e SURVEYING TOOLS", "is_usap_dc": false, "keywords": "SEISMOLOGICAL STATIONS; Ice Quakes; Ice Cliffs; Not provided; Taylor Glacier; FIELD SURVEYS; Remote Sensing; GROUND-BASED OBSERVATIONS; Modeling; Ice Deformation; Glacial Meltwater; FIELD INVESTIGATION; McMurdo Dry Valleys", "locations": "McMurdo Dry Valleys; Taylor Glacier", "north": -77.73, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Pettit, Erin; Hallet, Bernard; Fountain, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e SEISMOLOGICAL STATIONS; Not provided", "repositories": null, "science_programs": null, "south": -77.733, "title": "Collaborative Research: Mechanics of Dry-Land Calving of Ice Cliffs", "uid": "p0000721", "west": 162.132}, {"awards": "0542293 Winckler, Gisela", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 17 Dec 2007 00:00:00 GMT", "description": "This Small Grant for Exploratory Research supports development of an innovative dating technique for application to ancient, relict ice bodies buried in the Western Dry Valleys of Antarctica. Dating of surrounding sediments and volcanic ashes indicates that these ice bodies may be up to six million years in age, offering the oldest direct atmospheric and climate records available. This SGER is a proof of concept to develop a new dating technique using beryllium (10Be) of cosmogenic origin from the atmosphere and extraterrestrial helium (3He) contained in interplanetary dust particles. Both tracers are deposited to the Earth\u0027s surface and likely incorporated into the ice matrix at constant rates. Radioactive decay of 10Be versus the stable extraterrestrial 3He signal may offer way to directly measure the age of the ice.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this work are development of a new analytical technique that may improve society\u0027s understanding of the potential for global climate change from the perspective of the deep time record.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "Cosmogenic Radionuclides; Old Ice; Idp; FIELD INVESTIGATION", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Winckler, Gisela", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": null, "title": "Direct Dating of Old Ice by Extraterrestrial Helium-3 and Atmospheric Beryllium-10 - A Proof of Concept", "uid": "p0000127", "west": null}, {"awards": "0338244 Schaefer, Joerg", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 10 Dec 2007 00:00:00 GMT", "description": "This project will determine the age, origin, and climatic significance of buried ice found in the western Dry Valleys of Antarctica. Previous studies indicate that this ice may be over a million years in age, making it by far the oldest ice yet discovered on Earth. An alternative view is that this ice is represents recently frozen groundwater. To distinguish between these hypotheses and characterize the ice, we are undertaking an interdisciplinary research program focused on: 1) understanding the surface processes that permit ice preservation; and 2) testing the efficacy of cosmogenic nuclides and 40Ar/39Ar analyses in dating both tills and volcanic ash associated with the ice. Our plan calls for the analysis of a minimum of six cosmogenic depth profiles to determine if and how cryoturbation reworks sublimation tills and assess the average rate of ice sublimation for three debris-covered glaciers. We will model through finite- element analyses at least three buried glaciers and compare flow rates with those based on radiometric dating of surface deposits. Ten ice cores will also be collected for measurement of d18O, dD, ice fabric, ice texture, total gas content/composition. Better understanding of surface processes above buried ice will permit researchers to gain access to a record of atmospheric and climate change that could well cover intervals that predate Quaternary time. The work may also add valuable insight into Martian history. In terms of broader impacts, we have recruited three female PhD students and developed interdisciplinary collaborations among geochemists at Columbia University, planetary geologists at Brown University, geomorphologists at Boston University, and numerical modelers at the University of Maine.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "FIELD INVESTIGATION", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Schaefer, Joerg", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Age, Origin and Climatic Significance of Buried Ice in the Western Dry Valleys, Antarctica", "uid": "p0000255", "west": null}, {"awards": "0338224 Putkonen, Jaakko", "bounds_geometry": "POLYGON((161 -77,161.3 -77,161.6 -77,161.9 -77,162.2 -77,162.5 -77,162.8 -77,163.1 -77,163.4 -77,163.7 -77,164 -77,164 -77.1,164 -77.2,164 -77.3,164 -77.4,164 -77.5,164 -77.6,164 -77.7,164 -77.8,164 -77.9,164 -78,163.7 -78,163.4 -78,163.1 -78,162.8 -78,162.5 -78,162.2 -78,161.9 -78,161.6 -78,161.3 -78,161 -78,161 -77.9,161 -77.8,161 -77.7,161 -77.6,161 -77.5,161 -77.4,161 -77.3,161 -77.2,161 -77.1,161 -77))", "dataset_titles": "Cosmogenic nucilde data at ICE-D", "datasets": [{"dataset_uid": "200298", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nucilde data at ICE-D", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Tue, 20 Nov 2007 00:00:00 GMT", "description": "This work will study cosmogenic isotope profiles of rock and sediment in the Dry Valleys of Antarctica to understand their origin. The results will provide important constraints on the history of the East Antarctic Ice Sheet. The near-perfect preservation of volcanic ash and overlying sediments suggests that hyperarid cold conditions have prevailed in the Dry Valleys for over 10 Myr. The survival of these sediments also suggests that warm-based ice has not entered the valley system and ice sheet expansion has been minimal. Other evidence, however, suggests that the Dry Valleys have experienced considerably more sediment erosion than generally believed: 1) the cosmogenic exposure ages of boulders and bedrock in the Valleys all show generally younger ages than volcanic ash deposits used to determine minimum ages of moraines and drifts, 2) there appears to be a discrepancy between the suggested extreme preservation of unconsolidated slope deposits (\u003e10 Myr) and adjacent bedrock that has eroded 2.6-6 m during the same time interval. The fact that the till and moraine exposure ages generally post date the overlying volcanic ash deposits could reflect expansion of continental ice sheet into the Dry Valleys with cold-based ice, thus both preserving the landscape and shielding the surfaces from cosmic radiation. Another plausible explanation of the young cosmogenic exposure ages is erosion of the sediments and gradual exhumation of formerly buried boulders to the surface. Cosmogenic isotope systematics are especially well suited to address these questions. We will measure multiple cosmogenic isotopes in profiles of rock and sediment to determine the minimum exposure ages, the degree of soil stability or mixing, and the shielding history of surfaces by cold based ice. We expect to obtain unambiguous minimum ages for deposits. In addition, we should be able to identify areas disturbed by periglacial activity, constrain the timing of such activity, and account for the patchy preservation of important stratigraphic markers such as volcanic ash. The broader impacts of this project include graduate and undergraduate education, and improving our understanding of the dynamics of Southern Hemisphere climate on timescales of millions of years, which has major implications for understanding the controls and impacts of global climate change.", "east": 164.0, "geometry": "POINT(162.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Dry Valleys; Not provided", "locations": "Dry Valleys", "north": -77.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Putkonen, Jaakko", "platforms": "Not provided", "repo": "ICE-D", "repositories": "ICE-D", "science_programs": null, "south": -78.0, "title": "Stability of Landscapes and Ice Sheets in Dry Valleys, Antarctica: A Systematic Study of Exposure Ages of Soils and Surface Deposits", "uid": "p0000575", "west": 161.0}, {"awards": "9909436 Farley, Kenneth", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 11 Jul 2007 00:00:00 GMT", "description": "9909436 \u003cbr/\u003eFarley\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic.\u003cbr/\u003e\u003cbr/\u003eThis project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a \"warm\" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the \"dynamic\" ice sheet model) or the middle Miocene (the \"stable\" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming.\u003cbr/\u003e\u003cbr/\u003eThe specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Farley, Kenneth", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Exhumation of the Transantarctic Mountains: Constraints from (U-Th)/He Dating of Apatites", "uid": "p0000281", "west": null}, {"awards": "0126202 Blankenship, Donald; 0125579 Cuffey, Kurt", "bounds_geometry": "POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))", "dataset_titles": "Ablation Rates of Taylor Glacier, Antarctica; Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica; Surface Velocities of Taylor Glacier, Antarctica", "datasets": [{"dataset_uid": "609324", "doi": "10.7265/N5RV0KM7", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Taylor Glacier", "people": "Bliss, Andrew; Cuffey, Kurt M.; Kavanaugh, Jeffrey; Aciego, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Surface Velocities of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609324"}, {"dataset_uid": "609326", "doi": "10.7265/N5N29TW8", "keywords": "Ablation Poles; Ablation Rates; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Taylor Glacier", "people": "Bliss, Andrew; Kavanaugh, Jeffrey; Cuffey, Kurt M.", "repository": "USAP-DC", "science_program": null, "title": "Ablation Rates of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609326"}, {"dataset_uid": "609323", "doi": "10.7265/N5WM1BBZ", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Isotope; Taylor Glacier", "people": "Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah; Cuffey, Kurt M.", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609323"}], "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.", "east": 162.5, "geometry": "POINT(161.25 -77.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Glacier; Glacier Surface; Glacier Surface Ablation; Ice Velocity; Velocity Measurements; Taylor Glacier; Isotope; GPS; Ice Sheet Elevation; Not provided; FIELD INVESTIGATION; Ice Surface Elevation; Ablation; Oxygen Isotope; Elevation; Deuterium; GROUND-BASED OBSERVATIONS; Glacier Surface Ablation Rate; Surface Elevation", "locations": "Taylor Glacier", "north": -77.6, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah; Cuffey, Kurt M.; Morse, David L.; Blankenship, Donald D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System", "uid": "p0000084", "west": 160.0}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}]
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Geodiversity is the variety of non-living elements like rocks, landforms, and processes in a given area, and plays an especially critical role in Antarctica. Geodiversity provides the conditions in which life can develop and underpins all ecosystems on Earth. It also provides tangible services to people (like construction materials) as well as intangible benefits (such as scientific knowledge from ice cores and artistic inspiration from glaciers). Despite its importance, Antarctic geodiversity remains under-explored, under-described, and inadequately mapped. This knowledge gap is particularly concerning given the threats posed by increasing human activity and environmental and climate change. This project uses a variety of datasets to map Antarctic geodiversity, assess its benefits to people, and help identify priority locations for conservation. <br/><br/>Through an interdisciplinary and mixed-method approach, this research will fill a major gap in the current understanding and representations of the Antarctic. Using the McMurdo Dry Valleys as a case study, the researcher will combine geospatial data on geology, geomorphology, glaciology, and hydrology to map geodiversity of the region. This project will identify sites of key geosystem services by analyzing geospatial data on placenames, scientific samples, and a web-based participatory mapping survey. The geodiversity and geosystem services data will then be overlaid and combined to identify hotspots of geo-social diversity. The resulting maps will be compared with the region’s protected area boundaries to assess the fit-for-purpose of current environmental management and identify priority locations for future research and conservation. The fellow will promote Antarctic geodiversity broadly, including at UNESCO International Geodiversity Day.<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.
Perennially ice-covered lakes in the McMurdo Dry Valleys of Antarctica contain abundant microbial mats, and the export of this mat material can fertilize the surrounding polar desert ecosystems. These desert soils are one of the most organic-poor on earth yet host a community of microorganisms. Microbial mat material is exported from the shallow, gas-supersaturated regions of the lakes when gas bubbles form in the mats, lifting them to the ice cover. The perennial ice cover maintains gas supersaturation. These mats freeze in and are exported to the surrounding soils through ice ablation. The largest seasonal decrease and thinnest ice cover in the history of Lake Fryxell was recorded during the 2022-2023 Austral summer. In this thin ice year, the water column dissolved oxygen increased over prior observations, and the lake bottom surface area with bubble-disrupted mat was more than double that observed in 1980-1981 and 2006-2007. This work will constrain mat mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning to understand how future changing regional climate and predicted seasonal loss of lake ice cover will affect nutrient transport in the McMurdo Dry Valleys. Exceptional years of mat export are hypothesized to have the most significant impact on nutrient export to soil communities. Variability in mat liftoff may thus play a role in the McMurdo Dry Valleys ecosystem response to changing climate. The perennial ice cover of lakes in the McMurdo Dry Valleys of Antarctica modulates the transfer of gasses, organic and inorganic material, between the lakes and surrounding soils. The export of biomass in these lakes is driven by the supersaturation of atmospheric gasses in the shallow regions under perennial ice cover. Gas bubbles nucleate in the mats, producing buoyancy that lifts them to the bottom of the ice, where they freeze in and are exported to the surrounding soils through ice ablation. These mats represent a significant source of biomass and nutrients to the McMurdo Dry Valleys soils, which are among the most organic-poor on earth. Nevertheless, this biomass remains unaccounted for in organic carbon cycling models for the McMurdo Dry Valleys. Ice cover data from the McMurdo Dry Valleys Long Term Ecological Research Project shows that the ice thickness has undergone cyclical variation over the last 40 years, reaching the largest seasonal decrease and thinnest ice-cover in the recorded history of Lake Fryxell during the 2022-2023 austral summer. Preliminary work shows that the surface area with mat liftoff at Lake Fryxell is more than double that observed in 1980-1981 and 2006-2007, coinciding with this unprecedented thinning of the ice-cover and an increase in the water column dissolved O2. This research will constrain biomass mobilization within and out of Lake Fryxell in the McMurdo Dry Valleys during a period of unprecedented ice thinning. The researchers hypothesize that a thinner ice cover promotes more biomass mobilization by 1) stimulating additional production of gas bubbles from the existing gas-supersaturated waters during summertime photosynthesis to create microbial mat liftoff and 2) promoting mat liftoff in deeper, thicker microbial mats, and 3) that this biomass can be traced into the soils by characterizing its chemistry and modeling the most likely depositional settings. This work will use microbial mat samples, lake dissolved oxygen and photosynthetically active radiation data and underwater drone footage documenting the depth distribution of liftoff mats in January 2023, and long-term ice cover thickness, photosynthetically active radiation, and lake level change data collected by the McMurdo Dry Valleys Long Term Ecological Research Project to test hypotheses 1-3. The dispersal of the liftoff mat exposed at Lake Fryxell surface will be modeled using a Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Exceptional liftoff years like the present are hypothesized to have the most significant impact on the soil communities as the rates of soil respiration increase with the addition of carbon. However, continued warming in the next 10 - 40 years may result in seasonal loss of the ice cover and cessation of liftoff mat export.
The Lamont-Doherty Earth Observatory of Columbia University was awarded a multi-year grant (May 1, 2010- April 30, 2015) to develop an ice imaging system, or "IcePod," for use in measuring the surface and subsurface topography of ice sheets. IcePod will enable research on the effects of global climate change on ice sheets and the effects of sub-glacial water on potential sea-level rise. IcePod sensors are contained in a Common Science Support Pod and operated on NYANG LC-130 aircraft during routine and targeted missions over Greenland and Antarctica. The IcePod instrument package consists of ice-penetrating radar, infrared and visible cameras, laser altimeter, inertial measurement unit, GPS receiver and data acquisition system. IcePod will also enable other instruments to be used in the modular Common Science Support Pod, and will become a shared community research facility providing data to the science community. Funding will support activities in both Greenland and Antarctica needed to commission IcePod, to develop a data reduction flow and data delivery system for IcePod data, and to engineer a UPS to provide IcePod with clean, reliable power for system operation. <br/><br/>Evidence from satellites has documented that the amount of ice in both the earth's polar regions is decreasing as global temperatures increase. Understanding how this change is occurring and building an understanding of how fast these continent-sized pieces of ice will change in the future, is critical as society develops plans for adapting to changing coastlines. To measure change and understand the processes driving these changes requires the capacity to image the polat ice sheets and oceans from long-range aircraft. This award supplemented the original MRI-R2 program that developed innovative airborne imagery technology called IcePod. IcePod can be mounted on any LC-130, the aircraft used in the polar regions, for the major logistical support. The IcePod system was developed by engineers and scientists at Columbia University, working in close collaboration with the New York Air National Guard, who operate the ski-equipped LC-130 aircraft for the National Science Foundation in Antarctica and Greenland. The IcePod instrumentation package presently consists of: a scanning laser for precise measurements of the ice surface, visible and infrared imaging cameras to document the ice surface structure and temperature, ice-penetrating radar to recover the ice thickness and constrain the distribution of water at the ice sheet bed, and shallow-ice radar to measure snow accumulation. A magnetometer system is mounted inside the pod to recover information on the solid earth structure. Positioning of the IcePod during flights and the measurements are provided by precision GPS satellite data and inertial technology. A gravimeter, using its own rack, is also employed in conjunction with the IcePod sensor suite. The final commissioning of the system occurred in November - December 2014 in Antarctica as stipulated in the award. The IcePod was successfully operated in full polar conditions with a series of flights from McMurdo Station over the Ross Ice Shelf, the Ross Sea, the Dry Valleys, the Transantarctic Mountains and to South Pole. Protocol was also developed for data handling, robust data reduction, workflow and quality control and archiving of data. <br/><br/>The system is now available to the polar community for novel imaging applications.
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.
Varsani, Arvind; Porazinska, Dorota; Schmidt, Steven; Bergstrom, Anna
No dataset link provided
Cryoconite holes are sediment-filled melt holes in the surface of glaciers that can be important sites of active microbial life in an otherwise mostly frozen and barren landscape. Previous studies in the McMurdo Dry Valleys, Antarctica suggest that viral infections of microbes, and a general lack of fertilizers (i.e., nutrients), may be important factors shaping the development and functioning of microbial communities in cryoconite holes. The researchers propose an experimental approach to understand how nutrient limitation affects diversity (number of species) and overall abundance of microbes, and how the diversity and abundance of microbes in turn affects the diversity, abundance, and infection type of viruses that parasitize the microbes in cryoconite sediments. The researchers will use sediments previously collected from Antarctic glaciers that have varying concentrations of viruses and nutrients, to set up a nutrient-addition experiment to determine how nutrients affect microbial and viral population dynamics. The results will deepen our understanding of how microbial communities in general are shaped by nutrients and viruses and give new insights into the functioning of viruses in extremely cold environments. The researchers will publish their findings in scientific journals and will share their discoveries with K-12 students from rural schools in collaboration with the Pinhead Institute and will connect undergraduate students from under-represented minorities to polar research through participation in the universitys Science, Technology, Engineering & Mathematics Routes Uplift Research Program. Outreach will be achieved through videos produced and distributed by a professional science communicator. The research advances a National Science Foundation goal of expanding fundamental knowledge of Antarctic systems, biota, and processes by utilizing the unique characteristics of the Antarctic region as a science observing platform.
The Principal Investigators propose an experimental approach to understand how nutrient limitation affects microbial diversity and abundances and their cascading effects on virus diversity, abundance, and mode of infection (lysis vs. lysogeny) in Antarctic cryoconite holes. Cryoconite holes are ideal natural microcosms for manipulative studies, not available in other cryospheric ecosystems. The PIs will use previously collected cryoconite from across a gradient of both viral diversity and nutrient levels to address questions about key limiting nutrients and microbial-viral community dynamics in cryoconite sediments. Nutrient manipulation experiments will be conducted in a growth chamber that closely approximates the light and temperature regime of in situ cryoconite holes to test three core hypotheses: (1) phosphorus availability limits microbial productivity and abundance in cryoconite holes; (2) relaxing nutrient limitation in cryoconite from low-diversity glaciers will increase species diversity, leading microbial communities to resemble those found on more nutrient-rich glaciers; (3) relaxing nutrient limitation will increase the diversity and abundance of viruses by increasing the availability of suitable hosts, and decrease the prevalence of lysogenic infections. By manipulating nutrient limitation within a realistic range, this project will help verify hypothesized phosphorus limitation of Antarctic cryoconite holes and will extend understanding of the connections between nutrients, diversity, and viral infection dynamics in the cryosphere more generally. A better understanding of these dynamics in cryoconite sediments improves the ability of scientists to forecast future impacts of environmental changes in the cryosphere.
This award reflects NSF''s statutory mission and has been deemed worthy of support through evaluation using the Foundation''s intellectual merit and broader impacts review criteria.
The goal of this study is to identify and distinguish different source areas of glacial sediment in the McMurdo Dry Valleys, Antarctica to determine past glacial flow direction. Understanding ice flow is critical for determining how the Antarctic Ice Sheets have behaved in the past. Such insight is fundamental for allowing scientists to predict how the Antarctic Ice Sheets will evolve and, in turn, forecast how much and how fast sea level may rise. The project study site, the McMurdo Dry Valleys, contain a tremendous record of glacial deposits on land that extends back at least 14 million years. Chemistry of the rocks within the glacial deposits hold clues to the sources of ice that deposited the material. The chemical analyses of the glacial deposits will allow mapping of the former extent of glaciations providing a better understand of ice flow history. The mapping of the largest ice sheet expansion of the past 14 million years in the McMurdo Dry Valleys is of broad interest to the global climate change community. Undergraduate students comprise the majority of the field teams and will be responsible for sample preparation and analysis in the laboratory. <br/><br/>This project utilizes new geochemical techniques to test hypotheses about the source, extent, and flow patterns of the glacier ice that deposited glacial tills in the McMurdo Dry Valleys, Antarctica (MDV). The MDV contain an unparalleled terrestrial archive of glacial deposits, which record multiple sources of ice that deposited them. These include the northeast flowing ice that overrode the Transantarctic Mountains, the eastward expansion of the East Antarctic Ice Sheet, the westward extension of the Ross Ice Shelf representing an expansion of the West Antarctic Ice Sheet, and the growth of local alpine glaciers. The glacial tills and drifts in the Antarctic are typically isolated in patches or disjointed outcrop patterns making it difficult to correlate tills and determine their source. This project will undertake a systematic study of the tills in the McMurdo Dry Valleys to determine their provenance with a variety of geochemical techniques including major and minor element analyses with X-ray fluorescence, heavy mineral composition, soil salt concentration, and determining the uranium-lead (U-Pb) ages of zircon sands contained in these tills. The primary tool will be the age distribution of the population of detrital zircon in a glacial drift because it reflects the source of the tills and provides a unique geochemical "fingerprint" used to distinguish source areas while correlating units across different sites. A deliverable from this project will be a community available library of zircon fingerprints for mapped glacial tills from archived samples at the Polar Rock Repository and the systematic collection of samples in the MDV.<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.
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.
This research will provide new insights into the relationships and history of sharks, fish and limbed animals. Understanding these relationships forms the backbone for both basic and applied science because fish often serve as models of human traits and diseases. Some of the main lines of evidence for these relationships come from fossils in rocks over 380 million years old that were originally deposited as ancient rivers and streams. Because rocks of this type and age are abundantly exposed along a number of the dry valleys and mountains of Antarctica, the investigation of these areas holds exceptional promise for discoveries that can have a broad impact. The fieldwork will involve geological mapping and assessment of the rocks with detailed reconnaissance for the fossils that they may hold. Fossil discoveries form the backbone for public communication of the methods and results of scientific research-- these studies will be used as vehicles for training of students at multiple levels as well as communication of science to the broader non-science citizen base.<br/><br/>The discovery, description, and analysis of Middle to Late Devonian (390-355 Million years ago) vertebrates and depositional environments provide important data on the emergence of novel anatomical structures, faunas, and habitats during a critical interval in the history of life and earth. Biological innovation during this time includes the early evolution of freshwater fish, the origins of major groups of vertebrates (e.g., sharks, lobe and ray-finned fish, tetrapods), and the expansion and elaboration of non-marine ecosystems. Accordingly, expanding our knowledge of vertebrate diversity during the Middle and Late Devonian will provide new evidence on the relationships of the major groups of vertebrates, the assembly of novelties that ultimately enabled tetrapods to invade land, the origin and early evolution of sharks and their relatives, and the assembly and expansion of non-marine ecosystems generally. The Aztec Siltstone of Antarctica Middle-Late Devonian; Givetian-Frasnian Stages) has exceptional potential to produce new paleontological evidence of these events and to illuminate the temporal, ecological, and geographic context in which they occurred. It is essentially fossiliferous throughout its known exposure range, something that is rare for Middle-Late Devonian non-marine rocks anywhere in the world. In addition, fine-grained meandering stream deposits are abundantly exposed in the Aztec Siltstone and are recognized as an important locus for the discovery of well-preserved Devonian fish, including stem tetrapods and their relatives. Given the exceedingly fossiliferous nature of the Aztec Siltstone, the large number of taxa known only from partial material, and the amount of promising exposure yet to be worked, a dedicated reconnaissance, collection, and research effort is designed to recover important new fossil material and embed it in a stratigraphic and sedimentological context. The first major objective of this study is the recovery, preparation, and description of Middle-Late Devonian fossil taxa. Ensuing investigation of the phylogenetic affinities, taphonomic occurrence, and stratigraphic position of fossil assemblages will allow both local and global comparisons of biotic diversity. These analyses will inform: 1) higher level phylogenetic hypotheses of jawed vertebrates, 2) biostratigraphic and biogeographic analysis of the distribution of the Middle-Late Devonian fish, and 3) paleobiological investigation of the elaboration of terrestrial and freshwater habitats. The broader impacts are derived from the utility of paleontology and Antarctic expeditionary science as educational tools with powerful narratives. Specific goals include affiliations with local urban secondary schools (using established relationships for broadening participation) and collegiate and graduate training. Wider dissemination of knowledge to the general public is a direct product of ongoing interactions with national and international media (print, television, internet).
Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John
No dataset link provided
Part I: Non-technical description:
Water is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a remote method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training in high-school curricular programming in Native American communities of the Southwest U.S.
Part II: Technical description:
Terrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data needed to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from Native American communities in the Southwestern U.S., where similar desert conditions exist.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
ANDRILL is a scientific drilling program to investigate Antarctica's role in global climate change over the last sixty million years. The approach integrates geophysical surveys, new drilling technology, multidisciplinary core analysis, and ice sheet modeling to address four scientific themes: (1) the history of Antarctica's climate and ice sheets; (2) the evolution of polar biota and ecosystems; (3) the timing and nature of major tectonic and volcanic episodes; and (4) the role of Antarctica in the Earth's ocean-climate system. <br/><br/>This award initiates what may become a long-term program with drilling of two previously inaccessible sediment records beneath the McMurdo Ice Shelf and in South McMurdo Sound. These stratigraphic records cover critical time periods in the development of Antarctica's major ice sheets. The McMurdo Ice Shelf site focuses on the Ross Ice Shelf, whose size is a sensitive indicator of global climate change. It has recently undergone major calving events, and there is evidence of a thousand-kilometer contraction since the last glacial maximum. As a generator of cold bottom water, the shelf may also play a key role in ocean circulation. The core obtained from this site will also offer insight into sub-ice shelf sedimentary, biologic, and oceanographic processes; the history of Ross Island volcanism; and the flexural response of the lithosphere to volcanic loading, which is important for geophysical and tectonic studies of the region.<br/><br/>The South McMurdo Sound site is located adjacent to the Dry Valleys, and focuses on the major ice sheet overlying East Antarctica. A debate persists regarding the stability of this ice sheet. Evidence from the Dry Valleys supports contradictory conclusions; a stable ice sheet for at least the last fifteen million years or an active ice sheet that cycled through expansions and contractions as recently as a few millions of years ago. Constraining this history is critical to deep-time models of global climate change. The sediment cores will be used to construct an overall glacial and interglacial history for the region; including documentation of sea-ice coverage, sea level, terrestrial vegetation, and melt-water discharge events. The core will also provide a general chronostratigraphic framework for regional seismic studies and help unravel the area's complex tectonic history.<br/><br/>The broader impacts of this project include formal and informal education, new research infrastructure, various forms of collaboration, and improving society's understanding of global climate change. Education is supported at the postdoctoral, graduate, undergraduate, and K-12 levels. Teachers and curriculum specialists are integrated into the research program, and a range of video resources will be produced, including a science documentary for television release. New research infrastructure includes equipment for core analysis and ice sheet modeling, as well as development of a unique drilling system to penetrate ice shelves. Drill development and the overall project are co-supported by international collaboration with scientists and the National Antarctic programs of New Zealand, Germany, and Italy. The program also forges new collaborations between research and primarily undergraduate institutions within the United States. <br/><br/>As key factors in sea-level rise and oceanic and atmospheric circulation, Antarctica's ice sheets are important to society's understanding of global climate change. ANDRILL offers new data on marine and terrestrial temperatures, and changes our understanding of extreme climate events like the formation of polar ice caps. Such data are critical to developing accurate models of the Earth's climatic future.
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.
The McMurdo Dry Valleys are the largest ice-free region in Antarctica and home to a seasonally active hydrologic system, with streams and saline lakes. Streams are fed by summer meltwater from local glaciers and snowbanks. Therefore, streamflow is tied to summer climate conditions such as air temperatures, ground temperatures, winds, and incoming solar radiation. Based on 50 years of monitoring, summer stream activity has been observed to change, and it likely varied during the geologic past in response to regional climate change and fluctuating glaciers. Thus, deposits from these streams can address questions about past climate, meltwater, and lake level changes in this region. How did meltwater streamflow respond to past climate change? How did streamflow vary during periods of glacial advance and retreat? At what times did large lakes fill many of the valleys and what was their extent? The researchers plan to acquire a record of stream activity for the Dry Valleys that will span the three largest valleys and a time period of about 100,000 years. This record will come from a series of active and ancient alluvial fans that were deposited by streams as they flowed from valley sidewalls onto valley floors. The study will provide a long-term context with which to assess recent observed changes to stream activity and lake levels. The research will be led by two female mid-career investigators and contribute significantly to student research opportunities and education. The research will contribute to graduate and undergraduate education by including students in both field and laboratory research, as well as incorporating data and results into the classroom. The research will be disseminated to K-12 and non-scientific communities through outreach that includes professional development training for K-12 teachers in eastern Massachusetts, development of hands-on activities, visits to K-12 classrooms, and STEM education and literacy activities in North Carolina.
The PIs propose to constrain rates of fluvial deposition and periods of increased fluvial activity in the McMurdo Dry Valleys during the Holocene and late Pleistocene. During 50 years of hydrologic monitoring in the Dry Valleys, scientists have observed that streams exhibit significant response to summer conditions. Previous studies of glacial and lacustrine deposits indicate regional glacier advance in the Dry Valleys during recent interglacial periods and high lake levels during and after the Last Glacial Maximum (LGM), with potentially significant low and high stands during the Holocene. However, the geologic record of meltwater activity is poorly constrained. The PIs seek to develop the first spatially-extensive record of stream deposition in the Dry Valleys by analyzing and dating alluvial fans. Given that alluvial fans are deposited by summer meltwater streams in a relatively stable tectonic setting, this record will serve as a proxy of regional summer climate conditions. Meltwater streams are an important component of the regional hydrologic system, connecting glaciers to lakes and affecting ecosystems and soils. A record of fluvial deposition is key to understanding the relationship between past climate change and regional hydrology. The proposed research will include remote- and field-based mapping of alluvial fans, stream channels, and meltwater sources as well as modeling potential incoming solar radiation to the fans and moisture sources during the austral summer. In the field, the PIs will document stratigraphy, collect near-surface sediments from 25 fans across four valleys (Taylor, Pearse, Wright, and Victoria), and collect 2- to 3-m vertical cores of ice-cemented sediments from three alluvial fan complexes. The PIs will then conduct depositional dating of fluvial sands via optically stimulated luminescence, and analyze mineralogy and bulk major element chemistry with X-ray powder diffraction and X-ray fluorescence. From these analyses, the PIs propose to (1) determine the timing of local- to regional-scale periods of high fluvial deposition, (2) calculate depositional rates, and (3) constrain depositional environments and sediment provenance. Given that many of the alluvial fans occur below the hypothesized maximum extents of glacially-dammed lakes in Wright and Victoria valleys, detailed stratigraphy, sediment provenance, and OSL dating of these fans could shed light on ongoing debates regarding the timing and extent of LGM and post-LGM lakes. The work will support a postdoctoral researcher, a PhD student, and many undergraduate and master’s students in cross-disciplinary research that spans stratigraphy, geochemistry, paleoclimatology and physics.
This package contains data collected from microbial mat surveys (i.e., percent cover, ash-free dry mass (AFDM), and pigment concentrations – chlorophyll-a, scytonemin, and carotenoids) associated with satellite-derived Normalized Difference Vegetation Index (NDVI) values from the Lake Fryxell Basin of Taylor Valley, located in the McMurdo Dry Valleys of Antarctica. The purpose of this study was to quantitatively compare key microbial mat characteristics to NDVI. Data were collected at seven plot locations within the Canada Glacier Antarctic Specially Protected Area (ASPA) near Canada Stream, as well as alongside Green Creek and McKnight Creek. NDVI values were derived from a WorldView-2 multispectral satellite image taken of the Lake Fryxell Basin on January 19, 2018, while biological ground surveying and sampling were conducted during the 2nd and 4th weeks of January 2018.
The primary scientific goal of the proposed project is to test whether Taylor Valley, Antarctica has experienced glacial incision in the last ~1 million years in spite of cold climate conditions. One of the Dry Valleys of the Transantarctic Mountains, Taylor Valley exhibits over 2000 m of relief from sub sea-level troughs to high polar peaks. The Dry Valleys are characterized by low mean annual temperatures, paucity of precipitation and erosion that has allowed fragile glacial landforms, now subaerially exposed at high elevations, to be preserved for as long as 15 Ma. Two end member models can explain the timing of glacial incision and the observation that Quaternary advances of Taylor Glacier have left deposits at lower valley elevations with each advance. In the first scenario, all Valley relief is generated prior to 15 Ma when non-polar climates enabled warm-based glaciers to incise and widen fluvial channels more so than peaks. In this case, Quaternary drift deposits record advances of cold-based glaciers of decreasing ice volume. Limited glacial erosion and silt generation results in drift deposits composed primarily of recycled sediments. In the second scenario, selective erosion of the valley floor continues to deepen Taylor Valley over the last 2 Ma while high elevation peaks remain uneroded in polar conditions. The ‘bathtub rings’ of Quaternary drifts reaching a progressively lower elevation through time could be due to the lowering of the valley floor by subglacial erosion and with it, production of silt which is now incorporated into these drifts. While either scenario would result in the present day topography, they differ in the implied evolution of regional glacial ice volume over time and the timing of both valley relief production and generation of fine-grained particles. Here we propose to distinguish between these two models, by placing time constrains on fine particle production using U-series comminution dating. This new geochronologic tool exploits the loss of 234U due to alpha-recoil. The deficiency in 234U only becomes detectable in particles with a sufficiently high surface-area-to-volume ratio which can incur appreciable 234U loss (<50 m). The timing of comminution and particle size controls the magnitude of 234U loss, up to 10% in silt-sized particles comminuted over 1.5 million years ago. And while this geochronologic tool is in its infancy, the scientific goal of this proposal can be achieved by resolving between ancient and recently comminuted fine particles, a binary question that our preliminary modeling and measured data show is readily resolved.
The goal of this project is to discover whether the Antarctic scallop, Adamussium colbecki, provides a guide to sea-ice conditions in nearshore Antarctica today and in the past. Scallops may grow slower and live longer in habitats where sea ice persists for many years, limited by food, compared to habitats where sea ice melts out annually. Also, the chemicals retained in the shell during growth may provide crucial habitat information related to not only changing sea-ice conditions but also the type of food, whether it is recycled from the seafloor or produced by algae blooming when sea ice has melted. Unlocking the ecological imprint captured within the shell of the Antarctic Scallop will increase our understanding of changing sea-ice conditions in Antarctica. Further, because the Antarctic scallop had relatives living at the time when the Antarctic ice sheet first appeared, the scallop shell record may contain information on the stability of the ice sheet and the history of Antarctic shallow seas. Funding will also be integral for training a new generation of geoscientists in fossil and chemical forensics related to shallow sea habitats in Antarctica.
Scallops are worldwide in distribution, are integral for structuring marine communities have an extensive fossil record dating to the late Devonian, and are increasingly recognized as important paleoenvironmental proxies because they are generally well preserved in the sediment and rock record. The primary goal of this project is to assess the differences in growth, lifespan, and chemistry (stable isotopes, trace elements) archived in the shell of the Antarctic scallop that may be indicative of two ice states: persistent (multiannual) sea ice at Explorers Cove (EC) and annual sea ice (that melts out every year) at Bay of Sails (BOS), western McMurdo Sound, Antarctica. This project will investigate growth and lifespan proxies (physical and geochemical) and will use high-resolution records of stable oxygen isotopes to determine if a melt-water signal is archived in A. colbecki shells and whether that signal captures the differing ice behavior at two sites (EC versus BOS). Stable isotopes of carbon and nitrogen in association with trace elements will be used to examine subannual productivity spikes indicative of phytoplankton blooms, which are predicted to be more pronounced during open ocean conditions. Small growth increments in the outer calcite layer will be assessed to determine if they represent fortnightly growth, if so, they could provide a high-resolution proxy for monthly environmental processes. Unlocking the environmental archive preserved in A. colbecki shells may prove to be an important proxy for understanding changing sea-ice conditions in Antarctica's past. Funding will support a Ph.D. student and undergraduates from multiple institutions working on independent research projects. Web content focused on Antarctic marine communities will be designed for museum outreach, reaching thousands of middle-school children each year.
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.
As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high "weatherability" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth's carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential "weather ability" and investigate how sediment produced in these glacial systems could ultimately impact Earth's carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.
Physical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.
This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The proposed project will investigate the coldest and driest parts of the Transantarctic Mountains (Ong Valley at Nimrod Glacier and Moraine Canyon at Amundsen Glacier) where the lack of running water and biological activity in the modern environment is thought to have preserved the landscape, essentially unchanged, for millions of years. Contrary to this common belief, it is hypothesized that the landscape does evolve, perhaps as fast as many surfaces in the Dry Valleys area where both loose soil and bedrock surfaces have been degrading at a rate of about 1-2 m/Myrs for the past several million years. The research team will rely on analysis of the both stable and radioactive cosmogenic isotopes that accumulate in near surface soil and bedrock. Collectively these measurements allow comparison of the long term landscape evolution to current processes and environmental drivers such as wind speed. The results of this work will improve understanding of the evolution of the Earth's surface and directly aid in evaluating imagery of Martian geomorphology. Continued reliance on students provides a broader impact to this proposed research and firmly grounds this effort in its educational mission.
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.
Despite recent advances, we still know little about how life and its traces persist in extremely harsh conditions. What survival strategies do cells employ when pushed to their limit? Using a new technique, this project will investigate whether Antarctic paleolakes harbor "microbial seed banks," or caches of viable microbes adapted to past paleoenvironments that could help transform our understanding of how cells survive over ancient timescales. Findings from this investigation could also illuminate novel DNA repair pathways with possible biomedical and biotechnology applications and help to refine life detection strategies for Mars. The project will bring Antarctic research to Georgetown University''s campus for the first time, providing training opportunities in cutting edge analytical techniques for multiple students and a postdoctoral fellow. The field site will be the McMurdo Dry Valleys, which provide an unrivaled opportunity to investigate fundamental questions about the persistence of microbial life. Multiple lines of evidence, from interbedded and overlying ashfall deposits to parameterized models, suggest that the large-scale landforms there have remained essentially fixed as far back as the middle of the Miocene Epoch (i.e., ~8 million years ago). This geologic stability, coupled with geographic isolation and a steady polar climate, mean that biological activity has probably undergone few qualitative changes over the last one to two million years. The team will sample paleolake facies using sterile techniques from multiple Dry Valleys sites and extract DNA from entombed organic material. Genetic material will then be sequenced using Pacific Biosciences'' Single Molecule, Real-Time DNA sequencing technology, which sequences native DNA as opposed to amplified DNA, thereby eliminating PCR primer bias, and enables read lengths that have never before been possible. The data will be analyzed with a range of bioinformatic techniques, with results that stand to impact our understanding of cell biology, Antarctic paleobiology, microbiology and biogeography, biotechnology, and planetary science.
Tremblay, Marissa; Granger, Darryl; Balco, Gregory; Lamp, Jennifer
No dataset link provided
Part I: Nontechnical
Scientists study the Earth's past climate in order to understand how the climate will respond to ongoing global change in the future. One of the best analogs for future climate might the period that occurred approximately 3 million years ago, during an interval known as the mid-Pliocene Warm Period. During this period, the concentration of carbon dioxide in the atmosphere was similar to today's and sea level was 15 or more meters higher, due primarily to warming and consequent ice sheet melting in polar regions. However, the temperatures in polar regions during the mid-Pliocene Warm Period are not well determined, in part because we do not have records like ice cores that extend this far back in time. This project will provide constraints on surface temperatures in Antarctica during the mid-Pliocene Warm Period using a new type of climate proxy, known as cosmogenic noble gas paleothermometry. This project focuses on an area of Antarctica called the McMurdo Dry Valleys. In this area, climate models suggest that temperatures were more than 10 ºC warmer during the mid-Pliocene than they are today, but indirect geologic observations suggest that temperatures may have been similar to today. The McMurdo Dry Valleys are also a place where rocks have been exposed to Earth surface conditions for several million years, and where this new climate proxy can be readily applied. The team will reconstruct temperatures in the McMurdo Dry Valleys during the mid-Pliocene Warm Period in order to resolve the discrepancy between models and indirect geologic observations and provide much-needed constraints on the sensitivity of Antarctic ice sheets to warming temperatures. The temperature reconstructions generated in this project will have scientific impact in multiple disciplines, including climate science, glaciology, geomorphology, and planetary science. In addition, the project will (1) broaden the participation of underrepresented groups by supporting two early-career female principal investigators, (2) build STEM talent through the education and training of a graduate student, (3) enhance infrastructure for research via publication of a publicly-accessible, open-source code library, and (4) be broadly disseminated via social media, blog posts, publications, and conference presentations.
Part II: Technical Description
The mid-Pliocene Warm Period (3–3.3 million years ago) is the most recent interval of the geologic past when atmospheric CO2 concentrations exceeded 400 ppm, and is widely considered an analog for how Earths climate system will respond to current global change. Climate models predict polar amplification the occurrence of larger changes in temperatures at high latitudes than the global average due to a radiative forcing both during the mid-Pliocene Warm Period and due to current climate warming. However, the predicted magnitude of polar amplification is highly uncertain in both cases. The magnitude of polar amplification has important implications for the sensitivity of ice sheets to warming and the contribution of ice sheet melting to sea level change. Proxy-based constraints on polar surface air temperatures during the mid-Pliocene Warm Period are sparse to non-existent. In Antarctica, there is only indirect evidence for the magnitude of warming during this time. This project will provide constraints on surface temperatures in the McMurdo Dry Valleys of Antarctica during the mid-Pliocene Warm Period using a newly developed technique called cosmogenic noble gas (CNG) paleothermometry. CNG paleothermometry utilizes the diffusive behavior of cosmogenic 3He in quartz to quantify the temperatures rocks experience while exposed to cosmic-ray particles within a few meters of the Earths surface. The very low erosion rates and subzero temperatures characterizing the McMurdo Dry Valleys make this region uniquely suited for the application of CNG paleothermometry for addressing the question: what temperatures characterized the McMurdo Dry Valleys during the mid-Pliocene Warm Period? To address this question, the team will collect bedrock samples at several locations in the McMurdo Dry Valleys where erosion rates are known to be low enough that cosmic ray exposure extends into the mid-Pliocene or earlier. They will pair cosmogenic 3He measurements, which will record the thermal histories of our samples, with measurements of cosmogenic 10Be, 26Al, and 21Ne, which record samples exposure and erosion histories. We will also make in situ measurements of rock and air temperatures at sample sites in order to quantify the effect of radiative heating and develop a statistical relationship between rock and air temperatures, as well as conduct diffusion experiments to quantify the kinetics of 3He diffusion specific to each sample. This suite of observations will be used to model permissible thermal histories and place constraints on temperatures during the mid-Pliocene Warm Period interval of cosmic-ray exposure.
Beginning with the discovery of a "curious valley" in 1903 by Captain Scott, the McMurdo Dry Valleys (MDV) in Antarctica have been impacted by humans, although there were only three brief visits prior to 1950. Since the late 1950's, human activity in the MDV has become commonplace in summer, putting pressure on the region's fragile ecosystems through camp construction and inhabitation, cross-valley transport on foot and via vehicles, and scientific research that involves sampling and deployment of instruments. Historical photographs, put alongside information from written documentation, offer an invaluable record of the changing patterns of human activity in the MDV. Photographic images often show the physical extent of field camps and research sites, the activities that were taking place, and the environmental protection measures that were being followed. Historical photographs of the MDV, however, are scattered in different places around the world, often in private collections, and there is a real danger that many of these photos may be lost, along with the information they contain. This project will collect and digitize historical photographs of sites of human activity in the MDV from archives and private collections in the United States, New Zealand, and organize them both chronologically and spatially in a GIS database. Sites of past human activities will be re-photographed to provide comparisons with the present, and re-photography will assist in providing spatial data for historical photographs without obvious location information. The results of this analysis will support effective environmental management into the future. The digital photo archive will be openly available through the McMurdo Dry Valleys Long Term Ecological Research (MCM LTER) website (www.mcmlter.org), where it can be used by scientists, environmental managers, and others interested in the region. <br/><br/>The central question of this project can be reformulated as a hypothesis: Despite an overall increase in human activities in the MDV, the spatial range of these activities has become more confined over time as a result of an increased awareness of ecosystem fragility and efforts to manage the region. To address this hypothesis, the project will define the spatial distribution and temporal frequency of human activity in the MDV. Photographs and reports will be collected from archives with polar collections such as the National Archives of New Zealand in Wellington and Christchurch and the Byrd Polar Research Center in Ohio. Private photograph collections will be accessed through personal connections, social media, advertisements in periodicals such as The Polar Times, and other means. Re-photography in the field will follow established techniques and will create benchmarks for future research projects. The spatial data will be stored in an ArcGIS database for analysis and quantification of the human footprint over time in the MDV. The improved understanding of changing patterns of human activity in the MDV provided by this historical photo archive will provide three major contributions: 1) a fundamentally important historic accounting of human activity to support current environmental management of the MDV; 2) defining the location and type of human activity will be of immediate benefit in two important ways: a) places to avoid for scientists interested in sampling pristine landscapes, and, b) targets of opportunity for scientists investigating the long-term environmental legacy of human activity; and 3) this research will make an innovative contribution to knowledge of the environmental history of the MDV.
Intellectual Merit: This project will yield new information on the long term Antarctic climate and landscape evolution from measurements of cosmogenic nuclides in quartz sand from two unique permafrost cores collected in Beacon Valley, Antarctica. The two cores have already been drilled in ice-cemented, sand-rich permafrost at 5.5 and 30.6 meters depth, and are currently in cold storage at the University of Washington. The cores are believed to record the monotonic accumulation of sand that has been blown into lower Beacon Valley and inflated the surface over time. The rate of accumulation and any hiatus in the accumulation are believed to reflect in part the advance and retreat of the Taylor Glacier. Preliminary measurements of cosmogenically-produced beryllium (10Be) and aluminum (26Al) in quartz sand in the 5.5-meter depth core reveal that it has been accreting at a rate of 2.5 meters/Myr for the past million years. Furthermore, prior to that time, lower Beacon Valley was most likely covered (shielded from the atmosphere thereby having no or very low production of cosmogenic nuclides in quartz) by Taylor Glacier from 1 to 3.5 Myr BP. These preliminary measurements also suggest that the 30.6 meter core may provide a record of over 10 million years. The emphasis is the full characterization of the core and analysis of cosmogenic nuclides (including cosmogenic neon) in the 30.6 meter permafrost core to develop a burial history of the sands and potentially a record the waxing and waning of the Taylor Glacier. This will allow new tests of our current understanding of surface dynamics and climate history in the McMurdo Dry Valleys (MDV) based on the dated stratigraphy of eolian sand that has been accumulating and inflating the surface for millions of years. This is a new process of surface inflation whose extent has not been well documented, and holds the potential to develop a continuous history of surface burial and glacial expansion. This project will provide a new proxy for understanding the climatic history of the Dry Valleys and will test models for the evolution of permafrost in Beacon Valley.<br/><br/>Broader impacts: <br/><br/>The landscape history of the McMurdo Dry Valleys is important because geological deposits there comprise the richest terrestrial record available from Antarctica. By testing the current age model for these deposits, we will improve understanding of Antarctica?s role in global climate change. This project will train one graduate and one undergraduate student in geochemistry, geochronology, and glacial and periglacial geology. They will participate substantively in the research and are expected to develop their own original ideas. Results from this work will be incorporated into undergraduate and graduate teaching curricula, will be published in the peer reviewed literature, and the data will be made public.
This study aims to better understand salt accumulation in cold deserts and develop a model of salt transport by groundwater. Cold deserts, like the Antarctic McMurdo Dry Valleys (MDV), are similar to hot deserts in that they accumulate high concentrations of salts because there is not enough water to flush the salts out of the soils into the ocean. The accumulation of salt allows for the creation of brine-rich groundwater that freezes at much lower temperatures. Field work will focus on several groundwater features in the MDV including Don Juan Pond, a shallow lake that accumulates extremely high levels of salts and does not freeze until the temperature reaches -51 degrees C (-60 degrees F). The setting offers the potential to better understand this unique water environment including life at its extremes. It also serves as an analog environment for Mars, a planet that is entirely underlain by permafrost, similar to the MDV. This project will support a doctoral student at the University of Washington Department of Earth and Space Sciences, who will be trained in chemical analysis, chemical and physical modeling, and remote field work in a polar desert environment.<br/><br/>Past research suggests that the movement of soluble ions in sediment and soil is controlled by the water activity, permeability, and the thermal regime; however, processes controlling the ionic redistribution in Antarctic environments are poorly constrained. This project aims to better understand the formation, salt redistribution, and water activity of pervasive brine-rich groundwater that is enriched in calcium chloride. A primary goal is to develop a brine thermal;reactive;transport model for the MDV region using data collected from the field to constrain model inputs and ground-truth model outputs. The model will develop a Pitzer-type thermodynamic, reactive transport model and couple it to a ground temperature model. The model will test mechanisms of groundwater formation in the MDV and the properties (e.g. composition, temperature, and water activity) of widespread shallow brine-rich waters. Water is an essential ingredient for life and defining processes that control the availability of water is critical for understanding the habitability of extreme environments, including Mars.
Cryoconite holes are pockets of life completely encased in otherwise barren glacial ice. These pockets of life form when dust blown onto the ice melts a small, largely isolated hole that can function as its own tiny ecosystem. This dust can contain microorganisms such as bacteria, algae, or microscopic animals. The microorganisms within the hole interact and carry out functions typical of a larger ecosystem, such as a forest. Cryoconite holes are especially important in extreme cold environments such as the Antarctic Dry Valleys, where they function as repositories of life. Because cryoconite holes are mostly enclosed and persist for years, they can be tracked over time to test fundamental scientific questions about how communities of interacting organisms develop to become fully functioning ecosystems. This project will sample existing and experimentally created cryoconite holes to understand how these ecosystems develop and to what degree random processes (such as which organisms get there first) affect the final community composition and functioning. The results will not only improve our understanding of how microbial communities assemble and affect the functioning of microecosystems such as cryoconite holes, but also how the processes of community assembly affect functioning of larger ecosystems, such as forests. A better understanding of community establishment, development, and response to abiotic factors are essential to forecasting ecological responses to environmental change.<br/><br/>It is essential to unravel the links between community assembly, biodiversity, and nutrient cycling across numerous ecosystems because these are critical factors determining ecological responses to environmental change. The unique, largely isolated nature of cryoconite holes provides an experimental system that will advance fundamental understanding of the processes (e.g., stochastic dynamics such as dispersal limitation, assembly order, and ecological drift) driving community assembly. This project will use a field sampling campaign and a number of manipulative experiments to test a hypothesis that unites theory in community and ecosystem ecology: the degree to which stochastic processes guide microbial community assembly and affects regional patterns in biodiversity and ecosystem processes. Cryoconite holes will be sampled to compare community composition, environmental factors, and ecosystem functioning between hydrologically connected and isolated holes. New cryoconite holes will also be constructed and monitored over the course of two growing seasons to specifically alter assembly order and community size, thereby pairing a unique manipulative experiment with field surveys to address questions with relevance to the Antarctic and beyond. Amplicon sequencing, metagenomics, microscopy, sensitive environmental chemistry methods, and photosynthesis and respiration measurements will be used to test a series of sub-hypotheses that relate stochasticity to patterns in regional biodiversity, heterogeneity in environmental factors, and ecosystem processes.
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.
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.
Omelon, Christopher; Breecker, Daniel; Bennett, Philip
No dataset link provided
Cryptoendoliths are organisms that colonize microscopic cavities of rocks, which give them protection and allow them to inhabit extreme environments, such as the cold, arid desert of the Dry Valleys of Antarctica. Fossilized cryptoendoliths preserve the forms and features of organisms from the past and thus provide a unique opportunity to study the organisms' life histories and environments. To study this fossil record, there needs to be a better understanding of what environmental conditions allow these fossils to form. A climate gradient currently exists in the Dry Valleys that allows us to study living, dead, and fossilized cryptoendoliths from mild to increasingly harsh environments; providing insight to the limits of life and how these fossils are formed. This project will develop instruments to detect the biological activity of the live microorganisms and conduct laboratory experiments to determine the environmental limits of their survival. The project also will characterize the chemical and structural features of the living, dead, and fossilized cryptoendoliths to understand how they become fossilized. Knowing how microorganisms are preserved as fossils in cold and dry environments like Antarctica can help to refine methods that can be used to search for and identify evidence for extraterrestrial life in similar habitats on planets such as Mars. This project includes training of graduate and undergraduate students.
Little is known about cryptoendolithic microfossils and their formation processes in cold, arid terrestrial habitats of the Dry Valleys of Antarctica, where a legacy of activity is discernible in the form of biosignatures including inorganic materials and microbial fossils that preserve and indicate traces of past biological activity. The overarching goals of the proposed work are: (1) to determine how rates of microbial respiration and biodegradation of organic matter control microbial fossilization; and (2) to characterize microbial fossils and their living counterparts to elucidate mechanisms for fossilization. Using samples collected across an increasingly harsher (more cold and dry) climatic gradient that encompasses living, dead, and fossilized cryptoendolithic microorganisms, the proposed work will: (1) develop an instrument to be used in the field that can measure small concentrations of CO2 in cryptoendolithic habitats in situ; (2) use microscopy techniques to characterize endolithic microorganisms as well as the chemical and morphological characteristics of biosignatures and microbial fossils. A metagenomic survey of microbial communities in these samples will be used to characterize differences in diversity, identify if specific microorganisms (e.g. prokaryotes, eukaryotes) are more capable of surviving under these harsh climatic conditions, and to corroborate microscopic observations of the viability states of these microorganisms.
Recent discoveries of widespread liquid water and microbial ecosystems below the Antarctic ice sheets have generated considerable interest in studying Antarctic subglacial environments. Understanding subglacial hydrology, the persistence of life in extended isolation and the evolution and stability of subglacial habitats requires an integrated, interdisciplinary approach. The collaborative project, Minimally Invasive Direct Glacial Exploration (MIDGE) of the Biogeochemistry, Hydrology and Glaciology of Blood Falls, McMurdo Dry Valleys will integrate geophysical measurements, molecular microbial ecology and geochemical analyses to explore a unique Antarctic subglacial system known as Blood Falls. Blood Falls is a hypersaline, subglacial brine that supports an active microbial community. The subglacial brine is released from a crevasse at the surface of the Taylor Glacier providing an accessible portal into an Antarctic subglacial ecosystem. Recent geochemical and molecular analyses support a marine source for the salts and microorganisms in Blood Falls. The last time marine waters inundated this part of the McMurdo Dry Valleys was during the Late Tertiary, which suggests the brine is ancient. Still, no direct samples have been collected from the subglacial source to Blood Falls and little is known about the origin of this brine or the amount of time it has been sealed below Taylor Glacier. Radar profiles collected near Blood Falls delineate a possible fault in the subglacial substrate that may help explain the localized and episodic nature of brine release. However it remains unclear what triggers the episodic release of brine exclusively at the Blood Falls crevasse or the extent to which the brine is altered as it makes its way to the surface. <br/><br/>The MIDGE project aims to determine the mechanism of brine release at Blood Falls, evaluate changes in the geochemistry and the microbial community within the englacial conduit and assess if Blood Falls waters have a distinct impact on the thermal and stress state of Taylor Glacier, one of the most studied polar glaciers in Antarctica. The geophysical study of the glaciological structure and mechanism of brine release will use GPR, GPS, and a small passive seismic network. Together with international collaborators, the 'Ice Mole' team from FH Aachen University of Applied Sciences, Germany (funded by the German Aerospace Center, DLR), MIDGE will develop and deploy innovative, minimally invasive technologies for clean access and brine sample retrieval from deep within the Blood Falls drainage system. These technologies will allow for the collection of samples of the brine away from the surface (up to tens of meters) for geochemical analyses and microbial structure-function experiments. There is concern over the contamination of pristine subglacial environments from chemical and biological materials inherent in the drilling process; and MIDGE will provide data on the efficacy of thermoelectric probes for clean access and retrieval of representative subglacial samples. Antarctic subglacial environments provide an excellent opportunity for researching survivability and adaptability of microbial life and are potential terrestrial analogues for life habitats on icy planetary bodies. The MIDGE project offers a portable, versatile, clean alternative to hot water and mechanical drilling and will enable the exploration of subglacial hydrology and ecosystem function while making significant progress towards developing technologies for minimally invasive and clean sampling of icy systems.
The McMurdo Dry Valleys in Antarctica are recognized as being the driest, coldest and probably one of the harshest environments on Earth. In addition to the lack of water, the biota in the valleys face a very limited supply of nutrients such as nitrogen compounds - necessary for protein synthesis. The glacial streams of the Dry Valleys have extensive cyanobacterial (blue green algae) mats that are a major source of carbon and nitrogen compounds to biota in this region. While cyanobacteria in streams are important as a source of these compounds, other non-photosynthetic bacteria also contribute a significant fraction (~50%) of fixed nitrogen compounds to valley biota. This research effort will involve an examination of exactly which non-phototrophic bacteria are involved in nitrogen fixation and what environmental factors are responsible for controlling nitrogen fixation by these microbes. This work will resolve the environmental factors that control the activity, abundance and diversity of nitrogen-fixing microbes across four of the McMurdo Dry Valleys. This will allow for comparisons among sites of differing latitude, temperature, elevation and exposure to water. These results will be integrated into a landscape wetness model that will help determine the impact of both cyanobacterial and non-photosynthetic nitrogen fixing microorganisms in this very harsh environment.<br/><br/>The Dry Valleys in many ways resemble the Martian environment, and understanding the primitive life and very simple nutrient cycling in the Dry Valleys has relevance for understanding how life might have once existed on other planets. Furthermore, the study of microbes from extreme environments has resulted in numerous biotechnological applications such as the polymerase chain reaction for amplifying DNA and mechanisms for freeze resistance in agricultural crops. Thus, this research should yield insights into how biota survive in extreme environments, and these insights could lead to other commercial applications.
Building on previously funded NSF research, the use of paleobiological and paleogenetic data from mummified elephant seal carcasses found along the Dry Valleys and Victoria Land Coast in areas that today are too cold to support seal colonies (Mirougina leonina; southern elephant seals; SES) supports the former existence of these seals in this region. The occurrence and then subsequent disappearance of these SES colonies is consistent with major shifts in the Holocene climate to much colder conditions at the last ~1000 years BCE). <br/><br/>Further analysis of the preserved remains of three other abundant pinnipeds ? crabeater (Lobodon carciophagus), Weddell (Leptonychotes weddelli) and leopard (Hydrurga leptonyx) will be studied to track changes in their population size (revealed by DNA analysis) and their diet (studied via stable isotope analysis). Combined with known differences in life history, preferred ice habitat and ecosystem sensitivity among these species, this paleoclimate proxy data will be used to assess their exposure and sensitivity to climate change in the Ross Sea region during the past ~1-2,000 years
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.
The McMurdo Dry Valleys (MDV) is a polar desert on the coast of East Antarctica, a region that has not yet experienced climate warming. The McMurdo Dry Valleys Long Term Ecological Research (MCMLTER) project has documented the ecological responses of the glacier, soil, stream and lake ecosystems in the MDV during a cooling trend (from 1986 to 2000) which was associated with the depletion of atmospheric ozone. In the past decade, warming events with strong katabatic winds occurred during two summers and the resulting high streamflows and sediment deposition changed the dry valley landscape, possibly presaging conditions that will occur when the ozone hole recovers. In anticipation of future warming in Antarctica, the overarching hypothesis of the proposed project is: Climate warming in the McMurdo Dry Valley ecosystem will amplify connectivity among landscape units leading to enhanced coupling of nutrient cycles across landscapes, and increased biodiversity and productivity within the ecosystem. Warming in the MDV is hypothesized to act as a slowly developing, long-term press of warmer summers, upon which transient pulse events of high summer flows and strong katabatic winds will be overprinted. Four specific hypotheses address the ways in which pulses of water and wind will influence contemporary and future ecosystem structure, function and connectivity. Because windborne transport of biota is a key aspect of enhanced connectivity from katabatic winds, new monitoring will include high-resolution measurements of aeolian particle flux. Importantly, integrative genomics will be employed to understand the responses of specific organisms to the increased connectivity. The project will also include a novel social science component that will use environmental history to examine interactions between human activity, scientific research, and environmental change in the MDV over the past 100 years. To disseminate this research broadly, MCM scientists will participate in a wide array of outreach efforts ranging from presentations in K-12 classrooms to bringing undergraduates and teachers to the MDV to gain research experience. Planned outreach programs will build upon activities conducted during the International Polar Year (2007-2008), which include development of an interactive DVD for high school students and teachers and publication of a children's book in the LTER Schoolyard Book Series. A teacher's edition of the book with a CD containing lesson plans will be distributed. The project will develop programs for groups traditionally underrepresented in science arenas by publishing some outreach materials in Spanish.
Collaborative Research: THE MCMURDO DRY VALLEYS: A Landscape on the Threshold of Change is supported by the Antarctic Integrated System Science (AISS) program in the Antarctic Sciences Section of the Division of Polar Programs within the Geosciences Directorate of the National Sciences Foundation (NSF). The funds will support the collection of state-of-the-art high resolution LIDAR (combining the terms light and radar) imagery of the Dry Valleys of Antarctica in the 2014/2015 Antarctic field season, with LIDAR data collection and processing being provided by the NSF-supported NCALM (National Center for Airborne Laser Mapping) facility. LIDAR images collected in 2014/2015 will be compared to images from 2001 in order to detect decadal change. Additional fieldwork will look at the distribution of buried massive ice, and the impacts that major changes like slumping are having on the biota. All field data will be used to improve models on energy balance, and hydrology.<br/><br/>Intellectual Merit: There have been dramatic changes over the past decade in the McMurdo Dry Valleys: rivers are incising by more than three meters, and thermokarst slumps are appearing near several streams and lakes. These observations have all been made by researchers in the field, but none of the changes have been mapped on a valley-wide scale. This award will provide a new baseline map for the entire Dry Valley system, with high-resolution imagery provided for the valley floors, and lower resolution imagery available for the higher elevation areas that are undergoing less change. The project will test the idea that sediment-covered ice is associated with the most dramatic changes, due to differential impacts of the increased solar radiation on sediment-covered compared to clean ice, and despite the current trend of slightly cooling air temperatures within the Dry Valleys. Information collected on the topography, coupled with the GPR determined buried ice distributions, will also be incorporated into improved energy and hydrological models. In addition to providing the new high-resolution digital elevation model (DEM), the project will ultimately result in identification of areas that are susceptible to sediment-enhanced melt-driven change, providing a powerful prediction tool for the impacts of climate change.<br/><br/>Broader Impacts: The new DEM will be immediately useful to a wide range of disciplines, and will provide a comprehensive new baseline against which future changes will be compared. The project will provide a tool for the whole community to use, and the investigators will work with the community to make them aware of the new assets via public presentations, and perhaps via a workshop. The map will have international interest, and will also serve as a tool for environmental managers to draw on as they consider conservation plans. Several undergraduate and graduate students will participate in the project, and one of the co-PIs is a new investigator. The imagery collected is expected to be of interest to the general public in addition to scientific researchers, and venues for outreach such as museum exhibits and the internet will be explored. The proposed work is synergistic with 1) the co-located McMurdo LTER program, and 2) the NCALM facility that is also funded by the Geosciences Directorate.
Intellectual Merit: <br/>The MCM-SkyTEM project mapped resistivity in the McMurdo Dry Valleys and at Cape Barne on the Ross Island during the 2011-12 austral season using an airborne transient electromagnetic method. The SkyTEM system is mounted to a helicopter enabling a broad geophysical survey of subsurface resistivity structure over terrain that is inaccessible to traditional ground-based methods. Resistivity measurements obtained distinguish between highly resistive geologic materials such as glacier ice, bedrock and permafrost, and conductive materials such as unfrozen sediments or permafrost with liquid brine to depths of about 300 m. The PIs request funding to derive data products relevant to physical and chemical conditions in potential subsurface microbial habitats of the McMurdo Dry Valleys, similar cold regions on Earth and other planetary bodies. They will use these data products to characterize the hydrologic history of McMurdo Dry Valleys as well as the subsurface hydrologic connectivity in the region to investigate the implications for nutrient and microbial transport. The PIs will make these data products accessible to the research community. <br/><br/>Broader impacts: <br/>Polar microbial habitats are of high societal and scientific interest because they represent important testing grounds for the limits of life on Earth and other planetary bodies. Project deliverables will include teaching aids for undergraduate and graduate students. Two Ph.D. students will obtain advanced research training as part of this project. The PIs and students on this project will also engage in informal public outreach opportunities by presenting at local K-12 schools and reaching out to local media outlets on stories relating to SkyTEM research.
Many of the natural processes that modify the landscape inhabited by humans occur over very long timescales, making them difficult to observe. Exceptions include rare catastrophic events such as earthquakes, volcanic eruptions, and floods that occur on short timescales. Many significant processes that affect the land and landscape that we inhabit operate on time scales imperceptible to humans. One of these processes is wind transport of sand, with related impacts to exposed rock surfaces and man-made objects, including buildings, windshields, solar panels and wind-farm turbine blades. The goal of this project is to gain an understanding of wind erosion processes over long timescales, in the Antarctic Dry Valleys, a cold desert environment where there were no competing processes (such as rain and vegetation) that might mask the effects. The main objective is recovery of rock samples that were deployed in 1983/1984 at 11 locations in the Antarctic Dry Valleys, along with measurements on the rock samples and characterization of the sites. In the late 1980s and early 1990s some of these samples were returned and indicated more time was needed to accumulate information about the timescales and impacts of the wind erosion processes. This project will allow collection of the remaining samples from this experiment after 30 to 31 years of exposure. The field work will be carried out during the 2014/15 Austral summer. The results will allow direct measurement of the abrasion rate and hence the volumes and timescales of sand transport; this will conclude the longest direct examination of such processes ever conducted. Appropriate scaling of the results may be applied to buildings, vegetation (crops), and other aspects of human presence in sandy and windy locations, in order to better determine the impact of these processes and possible mitigation of the impacts. The project is a collaborative effort between a small business, Malin Space Science Systems (MSSS), and the University of Washington (UW). MSSS will highlight this Antarctic research on its web site, by developing thematic presentations describing our research and providing a broad range of visual materials. The public will be engaged through daily updates on a website and through links to material prepared for viewing in Google Earth. UW students will be involved in the laboratory work and in the interpretation of the results.<br>Technical Description of Project:<br>The goal of this project is to study the role of wind abrasion by entrained particles in the evolution of the McMurdo Dry Valleys in the Transantarctic Mountains. During the 1983 to 1984 field seasons, over 5000 rock targets were installed at five heights facing the 4 cardinal directions at 10 locations (with an additional site containing fewer targets) to study rates of physical weathering due primarily to eolian abrasion. In addition, rock cubes and cylinders were deployed at each site to examine effects of chemical weathering. The initial examination of samples returned after 1, 5, and 10 years of exposure, showed average contemporary abrasion rates consistent with those determined by cosmogenic isotope studies, but further stress that "average" should not be interpreted as meaning "uniform." The samples will be characterized using mass measurements wtih 0.01 mg precision balances, digital microphotography to compare the evolution of their surface features and textures, SEM imaging to examine the micro textures of abraded rock surfaces, and optical microscopy of thin sections of a few samples to examine the consequences of particle impacts extending below the abraded surfaces. As much as 60-80% of the abrasion measured in samples from 1984-1994 appears to have occurred during a few brief hours in 1984. This is consistent with theoretical models that suggest abrasion scales as the 5th power of wind velocity. The field work will allow return of multiple samples after three decades of exposure, which will provide a statistical sampling (beyond what is acquired by studying a single sample), and will yield the mass loss data in light of complementary environmental and sand kinetic energy flux data from other sources (e.g. LTER meteorology stations). This study promises to improve insights into one of the principal active geomorphic process in the Dry Valleys, an important cold desert environment, and the solid empirical database will provide general constraints on eolian abrasion under natural conditions.
Paragraph for Laypersons:<br/>This research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations.<br/><br/>Paragraph for Scientific Community:<br/>Rock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure<br/>dating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.
There are a number of areas of Antarctic research by scientists from the United States where rebreather technology (which unlike normal SCUBA diving releases few if any air bubbles) would be valuable tools. These include but are not limited to behavioral studies (because noise from bubbles released by standard SCUBA alters the behavior of many marine organisms), studies of communities on the underside of sea ice (because the bubbles disrupt the communities while or before they are sampled), and studies of highly stratified lake communities (because the bubbles cause mixing and because lighter line could be used to tether a diver to the surface which would probably also cause less water column disruption). The latter scientific advantage of less mixing in highly stratified (not naturally mixed) lakes is also a significant environmental advantage of rebreathers. However, for safety reasons, no US science projects will be approved for the use of rebreathers until they are tested by the US Antarctic Program (USAP). This award provides funds for the USAP Scientific Diving Officer to conduct such tests in conjunction with other diving professionals experienced in polar diving in general and specifically with rebreather technology in non-polar environments. A team of six scientific diving professionals will evaluate seven or more commercial rebreather models that are being most commonly used in non-polar scientific diving. This will be done through holes drilled or melted in sea ice at McMurdo Station, Antarctica. A limited number of test dives of the best performing models will subsequently be made in stratified lakes in the McMurdo Dry Valleys.
EAGER: Collaborative Research: Habitability of Antarctic lakes and detectability of microbial life in icy environments by autonomous year-round instrumentation, is supported by the Antarctic Integrated System Science (AISS) and the Antarctic Organisms and Ecosystems (AOE) programs within the Antarctic Sciences section in the Division of Polar Programs within the Geosciences Directorate of the National Sciences Foundation (NSF). The funds will allow the measurement of year-round properties of the microbes and the surrounding water in Lake Bonney, a lake with four meters of permanent ice cover over forty meters of liquid water in the Dry Valleys of Antarctica. NSF funds will be used to support the deployment, and the science enabled by the deployment, and NASA (the National Aeronautics and Space Administration) funds will be used to purchase the equipment.<br/><br/>Intellectual Merit: This research will be the first to make year-round measurements of the microbial community, and several associated environmental variables, in the continuously liquid portions of Lake Bonney, Antarctica. Three different types of equipment will be deployed in each of the lobes of Lake Bonney. The first instrument is an ITP (an ice-tethered profiler) that will measure physical parameters such as temperature, dissolved oxygen, and chlorophyll throughout the full depth of the liquid water portion of the lake, making measurements at least once each week. The second and third instruments will be used to collect discrete water samples at least every two weeks to determine A) the biological community (assessing metabolic and phylogenetic diversity) and B) the geochemistry (e.g., dissolved organic carbon, and dissolved inorganic nitrogen species). Such samplers have never been used to measure these properties year-round in the Antarctic. Cold temperatures, bottom lake water salinities that are four times greater than the ocean, the thick permanent ice cover, and the lack of sunlight to recharge batteries all present significant challenges for the project, thus classifying the work as an early, high-risk, high-reward activity (the acronym EAGER stands for Early-concept Grants for Exploratory Research).<br/><br/>Broader Impacts: There is much interest in understanding the ecosystems of the Polar regions in an era of climate change. Logistical limitations dictate much of this work only take place in the summer, until new autonomous technologies can open the door for year-round measurements. This award will be the first to attempt year-round microbial sampling in Antarctica. The McMurdo Dry Valleys region is also the site of a Long-Term Ecological Research (LTER) Program, and the research conducted on this project with benefit from, and contribute to, the larger LTER project. The instruments used in the project will be purchased by NASA, so two separate agencies have agreed to explore the feasibility of an early stage project. There will be at least three graduate student trained during the project, and the team will also participate in outreach activities at several venues including the Crow Reservation in Montana.
The McMurdo Dry Valleys in Antarctica are among the coldest, driest habitats on the planet. Previous research has documented the presence of surprisingly diverse microbial communities in the soils of the Dry Valleys despite these extreme conditions. However, the degree to which these organisms are active is unknown; it is possible that much of this diversity reflects microbes that have blown into this environment that are subsequently preserved in these cold, dry conditions. This research will use modern molecular techniques to answer a fundamental question regarding these communities: which organisms are active and how do they live in such extreme conditions? The research will include manipulations to explore how changes in water, salt and carbon affect the microbial community, to address the role that these organisms play in nutrient cycling in this environment. The results of this work will provide a broader understanding of how life adapts to such extreme conditions as well as the role of dormancy in the life history of microorganisms. Results will be widely disseminated through publications as well as through presentations at national and international meetings; raw data will be made available through a high-profile web-based portal. The research will support two graduate students, two undergraduate research assistants and a postdoctoral fellow. The results will be incorporated into a webinar targeted to secondary and post-secondary educators and a complimentary hands-on class activity kit will be developed and made available to various teacher and outreach organizations.
Intellectual Merit: <br/>The PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.<br/><br/>Broader impacts: <br/>This research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.
Intellectual Merit: <br/>The PIs propose a two-year project to map the distribution of climate-sensitive landforms throughout Northern Victoria Land between the Convoy Range and Cape Adare. This work will produce geospatial products to aid their geomorphic work on ice sheet stability and landscape evolution. Specifically, the PI will investigate the potential for extensive surface melting and ice-sheet retreat with modest warming in areas north of the Convoy Range in Northern Victoria Land. The hypothesis is that if key landform elements of the Dry Valleys assemblage are lacking in NVL it suggests a major variation in current climate conditions, and perhaps changes in climate evolution. The proposed work will also benefit the broader research community, as it will demonstrate the potential for using geospatial imagery in geomorphic research and produce geospatial products that can be used by other researchers. <br/><br/>Broader impacts: <br/>This work will help the research community better leverage the investment being made in the Polar Geospatial Center (PGC) and will help further demonstrate the significance of satellite imagery for doing ?virtual? field work in the Polar regions. More effective use of satellite imagery by field scientists in Antarctica will help reduce the logistical footprint on the Continent. The proposed research will support one graduate student at Boston University who will be trained in image analysis, map production, Antarctic geomorphology, and geospatial technologies. The proposed work will help to forge stronger links between PGC and Boston University?s Digital Image Analyses Lab (DIAL).
Intellectual Merit: <br/>The PIs propose to investigate the impact of earth surface processes on the application of cosmogenic exposure dating in Antarctica by combining multi-nuclide techniques, detailed field experiments, rock-mechanic studies, and climate modeling. They will analyze cosmogenic-nuclide inventories for a suite of six alpine-moraine systems in inland regions of the McMurdo Dry Valleys. This area is ideally suited for this study because 1) the targeted alpine moraine sequences are critically important in helping to reconstruct past temperature and precipitation values over the last several million years, 2) the production rates for cosmogenic nuclides are typically high and well-known, and 3) the complexity of surface processes is relatively low. Their work has two specific goals: to evaluate the effects of episodic geomorphic events in modulating cosmogenic inventories in surface rocks in polar deserts and to generate an alpine glacier chronology that will serve as a robust record of regional climate variation over the last several million years. A key objective is to produce a unique sampling strategy that yields consistent exposure-age results by minimizing the effects of episodic geomorphic events that obfuscate cosmogenic-nuclide chronologies. They will link their moraine chronology with regional-scale atmospheric models developed by collaborators at University of Massachusetts Amherst.<br/><br/>Broader impacts: <br/>This research is interdisciplinary and includes two early career scientists. Results of this work will be used to enhance undergraduate education by engaging two female students in Antarctic field and summer research projects. Extended outreach includes development of virtual Antarctic field trips for Colgate University?s Ho Tung Visualization Laboratory and Boston University?s Antarctic Digital Image Analyses Laboratory. The PIs will continue to work with the Los Angeles Valley Community College, which serves students of mostly Hispanic origin as part of the PolarTREC program. This project will contribute to the collaboration between LDEO and several New York City public high schools within the Lamont-Doherty Secondary School Field Program.
Intellectual Merit: <br/>The PIs propose to quantify the hillslope water, solute, and carbon budgets for Taylor Valley in the McMurdo Dry Valleys, using water tracks to investigate near-surface geological processes and challenge the paradigm that shallow groundwater is minimal or non-exixtant. Water tracks are linear zones of high soil moisture that route shallow groundwater downslope in permafrost dominated soils. Four hypotheses will be tested: 1) water tracks are important pathways for water and solute transport; 2) water tracks transport more dissolved silica than streams in Taylor Valley indicating they are the primary site of chemical weathering for cold desert soils and bedrock; 3) water tracks that drain highland terrains are dominated by humidity-separated brines while water tracks that drain lowland terrains are dominated by marine aerosols; 4) water tracks are the sites of the highest terrestrial soil carbon concentrations and the strongest CO2 fluxes in Taylor Valley and their carbon content increases with soil age, while carbon flux decreases with age. To test these hypotheses the PIs will carry out a suite of field measurements supported by modeling and remote sensing. They will install shallow permafrost wells in water tracks that span the range of geological, climatological, and topographic conditions in Taylor Valley. Multifrequency electromagnetic induction sounding of the upper ~1 m of the permafrost will create the first comprehensive map of soil moisture in Taylor Valley, and will permit direct quantification of water track discharge across the valley. The carbon contents of water track soils will be measured and linked to global carbon dynamics.<br/><br/>Broader impacts: <br/>Non-science majors at Oregon State University will be integrated into the proposed research through a new Global Environmental Change course focusing on the scientific method in Antarctica. Three undergraduate students, members of underrepresented minorities, will be entrained in the research, will contribute to all aspects of field and laboratory science, and will present results at national meetings.
Advances in molecular techniques have expanded our understanding of soil microbial communities, and raised important questions about regional and global patterns in microbial diversity. The proposed research will investigate the composition and activity of microbial communities across a range of geochemical and hydrologic soil conditions, and over local to regional scales in the Transantarctic Mountains, in order to assess controls over microbial biogeography. The research targets two areas in the Transantarctic mountains, the McMurdo Dry Valleys, and the Beardmore Glacier region further south, the latter representing an underexplored and inarguably more extreme soil environment. The research project will adopt an integrated approach, using molecular techniques and in situ assessment of biological activity in a quantitative biogeographical framework, with the goal of distinguishing fine versus broad scale controls over microbial community structure. The research is essential to determining the basic trophic status of extreme microbial food webs, and their sensitivity to climate change. The investigators will engage secondary and post-secondary educators through first person outreach as well as web-based communications and exercises. Two postdoctoral scientists will be trained in an interdisciplinary and international setting.
Intellectual Merit: <br/>Neogene sediment records recovered by ANDRILL suggest multiple events of open water conditions and elevated sea surface temperatures at times when terrestrial data from the McMurdo Dry Valleys indicate hyper arid, cold, desert conditions. Interpretation of the ANDRILL data suggests the West Antarctic Ice Sheet is highly sensitive to changes in Pliocene sea surface temperatures and this conclusion has been supported by recent Global Circulation Model results for the early to mid Pliocene. The PIs propose to model paleo-ice configurations and warm orbits associated with a WAIS collapse to assess potential climate change in East Antarctica. During such episodes of polar warmth they propose to answer: What is the limit of ablation along the East Antarctic Ice Sheet?; Are relict landforms in the Dry Valleys susceptible to modification from increase in maximum summertime temperatures?; and Is there sufficient increase in minimum wintertime temperatures to sustain a tundra environment in the Dry Valleys? Integration of depositional records and model outputs have the potential to test the performance of numerical models currently under development as part of ANDRILL; reconcile inconsistencies between marine and terrestrial paleoclimate records in high Southern Latitudes; and improve understanding of Antarctic climate and ice volume sensitivity to forcing for both the East Antarctic and West Antarctic Ice Sheets. <br/><br/>Broader impacts: <br/>Results from this study have the potential to be used widely by the research community. Outreach to local elementary schools from other funded efforts will continue and be extended to homeschooled students. A Post Doc will be supported as part of this award.
Intellectual Merit: <br/>Until recently, wetted soils in the Dry Valleys were generally only found adjacent to streams and lakes. Since the warm austral summer of 2002, numerous ?wet spots? have been observed far from shorelines on relatively flat valley floor locations and as downslope fingers of flow on valley walls. The source of the water to wet these soils is unclear, as is the spatial and temporal pattern of occurrence from year to year. Their significance is potentially great as enhanced soil moisture may change the thermodynamics, hydrology, and erosion rate of surface soils, and facilitate transport of materials that had previously been stable. These changes to the soil active layer could significantly modify permafrost and ground ice stability within the Dry Valleys. The PIs seek to investigate these changes to address two competing hypotheses: that the source of water to these ?wet spots? is ground ice melt and that the source of this water is snowmelt. The PIs will document the spatiotemporal dynamics of these wet areas using high frequency remote sensing data from Quickbird and Wordview satellites to document the occurrence, dimensions, and growth of wet spots during the 2010-Â11 and 2011-Â12 austral summers. They will test their hypotheses by determining whether wet spots recur in the same locations in each season, and they will compare present to past distribution using archived imagery. They will also determine whether spatial snow accumulation patterns and temporal ablation patterns are coincident with wet spot formation. <br/><br/>Broader impacts: <br/>One graduate student will be trained on this project. Findings will be reported at scientific meetings and published in peer reviewed journals. They will also develop a teaching module on remote sensing applications to hydrology for the Modular Curriculum for Hydrologic Advancement and an innovative prototype project designed to leverage public participation in mapping wet spots and snow patches across the Dry Valleys through the use of social media and mobile computing applications.
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.
The glacial streams of the McMurdo Dry Valleys have extensive cyanobacterial mats that are a probable source of fixed C and N to the Valleys. The research will examine the interplay between the microbial mats in the ephemeral glacial streams and the microbiota of the hyporheic soils (wetted soil zone) underlying and adjacent to those mats. It is hypothesized that the mats are important sources of organic carbon and fixed nitrogen for the soil communities of the hyporheic zone, and release dissolved organic carbon (DOC) and nitrogen (DON) that serves the entire Dry Valley ecosystem. Field efforts will entail both observational and experimental components. Direct comparisons will be made between the mats and microbial populations underlying naturally rehydrated and desiccated mat areas, and between mat areas in the melt streams of the Adams and Miers Glaciers in Miers Valley. Both physiological and phylogenetic indices of the soil microbiota will be examined. Observations will include estimates of rates of mat carbon and nitrogen fixation, soil respiration and leucine and thymidine uptake (as measures of protein & DNA synthesis, respectively) by soil bacteria, bacterial densities and their molecular ecology. Experimental manipulations will include experimental re-wetting of soils and observations of the time course of response of the microbial community. The research will integrate modern molecular genetic approaches (ARISA-DNA fingerprinting and ultra deep 16S rDNA microbial phylogenetic analysis) with geochemistry to study the diversity, ecology, and function of microbial communities that thrive in these extreme environments. The broader impacts of the project include research and educational opportunities for graduate students and a postdoctoral associate. The P.I.s will involve undergraduates as work-study students and in REU programs, and will participate in educational and outreach programs.
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.
This award will support the participation of US scientists in an international planning workshop devoted to discussions of how to best facilitate and coordinate international efforts for terrestrial system studies at the McMurdo Dry Valleys of Antarctica. To date, various aspects of the different Dry Valley landscape features (lakes, soils, glaciers, streams) and their biota have been studied most intensively by US and New Zealand scientists, but these efforts could significantly improve their explanatory power if they were coordinated so as to reduce redundancy, decrease environmental degradation and, most importantly, produce comparable datasets. Additionally, many of the present environmental management programs are based on the past baseline composition and location of biotic communities. As these communities become rearranged across the valleys in the future there is interest in assessing whether today's management plans are adequate. To efficiently move these research programs forward for the McMurdo Dry Valleys requires a coordinated, interdisciplinary, long-term data monitoring and observation network. <br/><br/>The ultimate objectives of the workshop are to: i) identify the optimal, complementary suites of measurements required to assess and address key processes associated with environmental change in Dry Valley ecosystems; ii) develop standards and protocols for gathering the most critical biotic and abiotic measurements associated with the key processes driving environmental change; iii) generate a draft data coordination and development plan that will maximize the utility of these data; iv) assess the effectiveness of current McMurdo Dry Valley ASMA (Antarctic Special Management Area) environmental protection guidelines.
This project characterizes wind-driven sediment transport in the McMurdo Dry Valleys of <br/>Antarctica during both winter and summer periods. Wind is the primary sculptor of<br/>terrain in this region and winter measurements, which have never been undertaken, are<br/>essential for determining the frequency and magnitude of transport events. The projects<br/>goal is to determine if the existing landforms represent relics from past climate regimes<br/>or contemporary processes. The project involves two major activities: (1) dynamic and<br/>time-integrated measurements of sand transport to characterize the seasonal behavior,<br/>frequency, and magnitude at four sites and (2) detailed surveying of an unusual<br/>wind-formed surface feature, the gravel megaripples found in the Wright Valley. In<br/>addition to interpreting Dry Valleys geomorphology, these data will provide a more<br/>quantitative assessment of wind-aided distribution of nutrients, plants, and animals to<br/>terrestrial and aquatic ecosystems throughout the Dry Valleys. This research will also<br/>provide quantitative information on the effects of extreme cold and low humidity on<br/>transport thresholds and rates, which can be applied to cold desert environments of the<br/>Arctic, Antarctic, and Mars.
Whillans, Wilson, Goad OPP 9527571 Abstract This award supports a project to initiate Global Positioning System (GPS) measurements for rock motions in South Victoria Land and vicinity. The results will be used to test some of the leading models for ice-sheet change and tectonism, in particular, whether the continent is rebounding due to reduced ice load from East or West Antarctica and whether there is tectonic motion due to Terror Rift or uplift of the Transantarctic Mountains. A modest program to measure ice motion will be conducted as well. The motive is to test models for ice flow in the Allan Hills meteorite concentration region and to determine whether small glaciers in the Dry Valleys are thickening or thinning. Monuments will be set into rock and ice and GPS receivers used to determine their locations. Repeats in later years will determine motion. Field activities will involve close cooperation with the USGS.
Intellectual Merit: <br/>The PI proposes a high-resolution paleoenvironmental study of pollen, spore, fresh-water algae, and dinoflagellate cyst assemblages to investigate the palynological record of sudden warming events in the Antarctic as recorded by the ANDRILL SMS drill core and terrestrial sections. These data will be used to derive causal mechanisms for these rapid climate events. Terrestrial samples will be obtained at various altitudes in the Dry Valleys region. The pollen and spores will provide data on atmospheric conditions, while the algae will provide data on sea-surface conditions. These data will help identify the triggers for sudden climatic shifts. If they are caused by changes in oceanic currents, a signal will be visible in the dinocyst assemblages first as currents influence their distribution. Conversely, if these shifts are triggered by atmospheric factors, then the shifts will first affect plants and be visible in the pollen record.<br/><br/>Broader impacts: <br/>The PI proposes a suite of activities to bring field-based climate change research to a broader audience. The PI will advise a diverse group of students and educators. The palynological data collected as part of this research will be utilized, in part, to develop new lectures on Antarctic palynology and these new lectures will be made available via a collaboration with the LSU HHMI program. In addition, the PI will direct three Louisiana middle-school teachers as they pursue a Masters of Natural Science for science educators. These teachers will help the PI develop a professional development program for science teachers. Community-based activities will be organized to raise science awareness and alert students and the public of opportunities in science.
Ice sheet models of the Last Glacial Maximum, and previous glaciation events in the Miocene, suggest that current low altitude, ice-free surfaces in Antarctica were completely covered with ice. If so, the terrestrial biota of Antarctica today would result from recolonization events after each glacial maximum. However, there is emerging evidence that much of the terrestrial Antarctic biota are of ancient origin and have somehow survived these glaciation events. The Transantarctic Mountains TRANsition Zone (TAM-TRANZ) plays a pivotal role in understanding the evolution and biogeographic history of today's Antarctic terrestrial biota, primarily because it contains numerous inland areas that could have served as refugia during glacial maxima. Due to its remote location, the TAM-TRANZ has not been systematically surveyed for animal biodiversity. Although an exhaustive survey of the region requires a multi-discipline, multi-year and multi-region effort, the research herein combines ecological, evolutionary and geophysical expertise to conduct an exploratory investigation of the extreme southern limits of biotic communities. The project will examine the historical geophysical requirements for the colonization and maintenance of functional ecosystems by multicellular organisms, and the feasibility and desirability to implement more systematic biogeographic studies in the future. Broader impacts include graduate and undergraduate student ownership of important subprojects that will provide research, presentation and publication opportunities. The investigators also will contribute to ongoing public education efforts through relationships with K-12 teachers and administrators in the public school districts where the project personnel reside. Finally, the project is leveraged by opportunistic collaboration with scientists associated with Antarctica New Zealand.
This project studies glaciovolcanic deposits at Minna Bluff in the western Ross Embayment of Antarctica. Its goal is to determine the history of the Ross Ice Shelf, which is fed by the major ice sheets from both East and West Antarctica. Apart from determining how these ice sheets waxed and waned during a period of dynamic climate change, glaciovolcanic sequences may constrain ice sheet parameters that are critical to numerical models such as thickness, hydrology, and basal thermal regime. This three-year study would map, analyze, and determine the age of key units using 40Ar/39Ar dating. Pilot studies would also be conducted for 36Cl dating of glacial deposits and stable isotope evaluations of alteration. The project offers a complementary record of Ross Ice Shelf behavior to that sampled by ANDRILL. It also improves the general record of McMurdo area volcanostratigraphy, which is important to interpreting landforms, glacial deposits, and ancient ice found in the Dry Valleys.<br/><br/>The broader impacts of this project include improving society's understanding of global climate change, sea level rise, and graduate and undergraduate student education. Outreach efforts include educational programs for public schools and community groups, exhibits for a local science museum, and a project website.
This project studies ancient ice buried in the Dry Valleys of Antarctica. The ice, which may approach ten million years in age, will be dated using argon and uranium radioisotope techniques. High-risk work, if successful it will offer the first and perhaps only samples of the Earth's atmosphere from millions of years in the past. These samples could offer critically important tests of paleoclimate records and proxies, as well as a glimpse into the characteristics of a past world much like the predicted future, warmer Earth. The broader impacts are graduate student education, and potentially contributing to society's understanding of global climate change and sea level rise.
Data collected on the permanently ice-covered lakes of the McMurdo Dry Valleys (MCM) during the late 1950's as part of the International Geophysical Year (IGY) showed that they were the only year round liquid water environments on the continent. Organisms in the lakes must possess novel physiological strategies that allow them to survive at low temperature and under extended darkness. Subsequent research has now shown that most organisms in the lakes are not just "surviving the extremes" but are actively feeding, growing and reproducing. However, nearly all research on the MCM lakes is restricted to the austral spring and summer when logistical support is provided. The unique aspects of physiological adaptation and metabolic function during the permanently cold and prolonged darkness of the Antarctic winter remain unknown. As part of the "International Polar Year 2007-2008" (IPY), the proposed research will study lakes within the Taylor Valley during the transition to polar night to test the overarching hypothesis that the onset of darkness induces a cascade of physiological changes that alters the functional role of autotrophic and heterotrophic microplankton within the lakes. This overarching theme will be addressed through an interdisciplinary study of selected biological components of the lake ecosystems using genomic and physiological tools to understand not only how individual organisms survive, but how they control ecosystem function during this seasonal transition. <br/><br/>This project is directly relevant to IPY objectives as it addresses a major identified theme (Adaptations to Life in Extreme Cold and Prolonged Darkness) with an international (UK, NZ),<br/>multidisciplinary team. The research has substantial broader impacts, as it will add to the body of long-term data accumulated by the MCM LTER and MCM Microbial Observatory projects in a synergistic manner; and it will include three undergraduates, a graduate student and two young female investigators. The project is linked to a highly visible education, outreach and human diversity programs supported by the McMurdo LTER, and initiates new outreach programs, including the Passport to Knowledge program.
0086645<br/>Fountain<br/><br/>This award supports a Small Grant for Exploratory Research (SGER) to study glaciological change in the McMurdo Dry Valleys, Antarctica under the category of "application of new expertise or new approaches to established research topics". The purpose of the project is to assess the application of classified imagery to the study of the magnitude and rate of change of glacier extent and lake area as an indicator of climate change. Because the rate of change of both glacier extent and lake area is small compared to the resolution of unclassified imagery, the increased resolution of classified imagery is clearly needed. Access to classified imagery with 1 meter or better resolution will provide a baseline measurement against which future changes can be compared. Maximum use will be made of archived imagery but if necessary, one request will be made for new imagery to supplement the existing archive. This work will support on-going field measurements which are part of the Long-Term Ecological Research (LTER) site in the McMurdo Dry Valleys but which are limited by logistic constraints to only a few measurements during limited times of the year. If successful, the information gained in this project will enable researchers to better direct their efforts to identify the important physical processes controlling the changes in the valleys. The information acquired in conducting this project will be made available to the public, using appropriate security procedures to declassify the data. The "exploratory" and "high risk" nature of the proposed work and its "potential" to make an important "impact" on the field of Antarctic glacier studies are all reasons that this work is appropriate to support as an SGER.
This project studies ancient lake deposits from the western Dry Valleys of Antarctica. These deposits are particularly exciting because they preserve flora and fauna over seven million years in age that represent the last vestiges of ecosystems that dominated this area before formation of the modern East Antarctic ice sheet. Their unique nature offers a chance to bridge modern and ancient ecology. Formed along the margin of ancient alpine glaciers, these deposits contain layers of silt, clay, and volcanic ash; as well as freeze-dried remnants of mosses, insects, and diatoms. Geological and biological analyses provide a view of the ecological and environmental conditions during mid-to-late Miocene--seven to seventeen million years ago--which spans the critical period when the East Antarctic ice sheet transitioned to its present stable form. The results place the modern lakes of the Dry Valleys into a long-term evolutionary framework, and allow for correlation and dating comparisons with other fossil-rich deposits from the Transantarctic Mountains. Chemical fingerprinting and dating of volcanic glass shards will also help date fossil- and ash-bearing horizons in nearby marine cores, such as those to be collected under the ANDRILL program. <br/><br/>The broader impacts are education at the postdoctoral, graduate, and undergraduate levels; and collaboration between a research institution and primarily undergraduate institution. The work also improves our understanding of global climate change during a critical period in the Earth's history.
This project studies the last vestiges of life in Antarctica from exceptionally well-preserved fossils of tundra life--mosses, diatoms, ostracods, Nothofagus leaves, wood, and insect remains recently discovered in ancient lake sediments from the McMurdo Dry Valleys. The area will be studied by an interdisciplinary team to elucidate information about climate and biogeography. These deposits offer unique and direct information about the characteristics of Antarctica during a key period in its history, the time when it was freezing. This information is critical for correlation with indirect proxies, such as though obtained from drill cores, for climate and state of the ice sheet. The results will also help understand the origin and migration of similar organisms found in South America, India and Australia.<br/><br/>In terms of broader impacts, this project supports an early career researcher, undergraduate and graduate student research, various forms of outreach to K12 students, and extensive international collaboration. The work also has societal relevance in that the outcomes will offer direct constraints on Antarctica's ice sheet during a time with atmospheric CO2 contents similar to those of the earth in the coming centuries, and thus may help predictive models of sea level rise.
This project is a field and laboratory based investigation of the Vanda dike swarm in the Dry Valleys of Antarctica. These dikes crosscut Cambro-Ordovician granitoid plutons produced during the Ross Orogeny, and mark the transition between the cessation of subduction and the onset of extensional magmatism. Many dying convergent plate margins convert to extensional magmatism, and the Dry Valleys provide a magnificent opportunity to examine the shallow roots of a plate that experienced this transition. Because of their exceptional exposure, bimodal felsic and mafic compositions, and complex field relations, the Vanda dikes have the potential to reveal insights into this important phase of Antarctic tectonic history. <br/>The broader impacts include collaboration between a primarily undergraduate and two research institutions, and support for undergraduate participation in an exciting, field-based research project.
Abstract<br/><br/>This project uses Aster and Hyperion remote sensing data combined with field observations and laboratory analysis to map soils in the McMurdo Dry Valleys of Antarctica. The goal is to use mineral abundances, compositions, and spatial heterogeneities to investigate the connections between microclimate and surface characteristics. The valleys are one of the most unique landscapes on earth. The outcomes will be relevant to understanding their geologic, biologic, and climactic history, and offer insight into the Martian landscape. The main broader impacts are graduate education and curriculum development involving K12 teachers.
This project seeks to answer a simple question: how old are potholes and related geomorphic features found in the uplands of the McMurdo Dry Valleys, Antarctica? Some research suggests that they are over ten million years old and date the growth of the East Antarctic Ice Sheet, the world?s largest. However, some evidence suggests that these are young, erosional features that continuing to evolve to this day. This project uses cosmogenic nuclide dating to determine the age of the pothole floors. The results are important for determining the ice sheet?s history and interpreting the O-isotope record from the marine sediment cores, key records of global climate. Broader impacts include K12 outreach and incorporation of outcomes into university courses.
This project uses cosmogenic nuclide dating and LIDAR studies of surface roughness to understand weathering and landscape evolution in the Dry Valleys of Antarctica. The work focuses on two processes: cryoturbation of frozen soils and the development of patterned, frozen ground on ancient lava flows. The approach includes innovative uses of He3 profiling. Results will also be applied to understanding the glacial history of the Dry Valleys. There are potential applications to understanding the history of the East Antarctic Ice Sheet and the formation of Martian landscapes. The broader impacts include graduate student education. As well, the work may contribute to our understanding of the history of the Antarctic ice sheets, which is important to modeling their behavior during global climate change.
Denitrification is the main process by which fixed nitrogen is lost from ecosystems and the regulation of this process may directly affect primary production and carbon cycling over short and long time scales. Previous investigations of the role of bioactive metals in regulating denitrification in bacteria from permanently ice-covered Lake Bonney in the Taylor Valley of East Antarctica indicated that denitrifying bacteria can be negatively affected by metals such as copper, iron, cadmium, lead, chromium, nickel, silver and zinc; and that there is a distinct difference in denitrifying activity between the east and west lobes of the lake. Low iron concentrations were found to exacerbate the potential toxicity of the other metals, while silver has the potential to specifically inhibit denitrification because of its ability to interfere with copper binding in redox proteins, such as nitrite reductase and nitrous oxide reductase. High silver concentrations might prevent the functioning of nitrous oxide reductase in the same way that simple copper limitation does, thereby causing the buildup of nitrous oxide and resulting in a nonfunctional nitrogen cycle. Other factors, such as oxygen concentration, are likely also to affect bacterial activity in Lake Bonney. This project will investigate silver toxicity, general metal toxicity and oxygen concentration to determine their effect on denitrification in the lake by using a suite of "sentinel" strains of denitrifying bacteria (isolated from the lake) incubated in Lake Bonney water and subjected to various treatments. The physiological responses of these strains to changes in metal and oxygen concentration will be quantified by flow cytometric detection of single cell molecular probes whose sensitivity and interpretation have been optimized for the sentinel strains. Understanding the relationships between metals and denitrification is expected to enhance our understanding of not only Lake Bonney's unusual nitrogen cycle, but more generally, of the potential role of metals in the regulation of microbial nitrogen transformations.<br/><br/>The broader impacts of this work include not only a better understanding of regional biogeochemistry and global perspectives on these processes; but also the training of graduate students and a substantial outreach effort for school children.
This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit of the project. We plan to collect intermediate-length ice cores (100-200m) at four sites along transects in Taylor Valley and Wright Valley, and analyze each core at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). A suite of statistical techniques will be applied to the multivariate glaciochemical dataset to identify chemical associations and to calibrate the time-series records with available instrumental data. Broader impacts of the project include: 1) contributions to several ongoing interdisciplinary Antarctic research programs; 2) graduate and undergraduate student involvement in field, laboratory, and data interpretation activities; 3) use of project data and ideas in several UMaine courses and outreach activities; and 4) data dissemination through peer-reviewed publications, UMaine and other paleoclimate data archive websites, and presentations at national and international meetings.
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.
0124049<br/>Berger<br/><br/>This award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.
This Small Grant for Exploratory Research explores the use of magnesium isotopes in understanding the preservation of ice in soils from the Dry Valleys of Antarctica. With such little precipitation in the region, this ice should have completely sublimed away, nonetheless there is geologic evidence of ten-million-year-old ice in some areas. Its ubiquitous presence in Dry Valley's soils implies some form of recharge, seemingly incompatible with the low precipitation rates. This project studies the Mg-isotopes found in soluble salts and, by association, water transport. Magnesium isotopes undergo mass dependent fractionation during the volatilization and condensation, and thus offer the possibility to constrain both the water source and other processes by which ice is mobilized. The measurements require the high precision made possible only recently by development of the MC-ICPMS. The method will be applied to Mg-salts extracted from archived Antarctic soils, as well as cores recovered by the 1970s Dry Valley Drilling Project. <br/><br/>In terms of broader impacts, this project would support a graduate student, who would learn cutting edge geochemical techniques while applying them to an exciting earth science question. This work is critical to understanding the environmental record offered by the Dry Valleys, including the deep ice records that may give seven-million year old samples of the earth's atmosphere. The work also has applications to understanding permafrost on Mars and interpreting recent rover observations.
This award supports a comprehensive study of land-based polar ice cliffs. Through field measurements, modeling, and remote sensing, the physics underlying the formation of ice cliffs at the margin of Taylor Glacier in the McMurdo Dry Valleys will be investigated. At three sites, measurements of ice deformation and temperature fields near the cliff face will be combined with existing energy balance data to quantify ice-cliff evolution over one full seasonal cycle. In addition, a small seismic network will monitor local "ice quakes" associated with calving events. Numerical modeling, validated by the field data, will enable determination of the sensitivity of ice cliff evolution to environmental variables. There are both local and global motivations for studying the ice cliffs of Taylor Glacier. On a global scale, this work will provide insight into the fundamental processes of calving and glacier terminus A better grasp of ice cliff processes will also improve boundary conditions required for predicting glaciers' response to climate change. Locally, the Taylor Glacier is an important component of the McMurdo Dry Valleys landscape and the results of this study will aid in defining ecologically-important sources of glacial meltwater and will lead to a better understanding of moraine formation at polar ice cliffs. This study will help launch the career of a female scientist, will support one graduate student, and provide experiential learning experiences for two undergraduates. The post-doctoral researcher will also use this research in the curriculum of a wilderness science experiential education program for high school girls.
This Small Grant for Exploratory Research supports development of an innovative dating technique for application to ancient, relict ice bodies buried in the Western Dry Valleys of Antarctica. Dating of surrounding sediments and volcanic ashes indicates that these ice bodies may be up to six million years in age, offering the oldest direct atmospheric and climate records available. This SGER is a proof of concept to develop a new dating technique using beryllium (10Be) of cosmogenic origin from the atmosphere and extraterrestrial helium (3He) contained in interplanetary dust particles. Both tracers are deposited to the Earth's surface and likely incorporated into the ice matrix at constant rates. Radioactive decay of 10Be versus the stable extraterrestrial 3He signal may offer way to directly measure the age of the ice.<br/><br/>The broader impacts of this work are development of a new analytical technique that may improve society's understanding of the potential for global climate change from the perspective of the deep time record.
This project will determine the age, origin, and climatic significance of buried ice found in the western Dry Valleys of Antarctica. Previous studies indicate that this ice may be over a million years in age, making it by far the oldest ice yet discovered on Earth. An alternative view is that this ice is represents recently frozen groundwater. To distinguish between these hypotheses and characterize the ice, we are undertaking an interdisciplinary research program focused on: 1) understanding the surface processes that permit ice preservation; and 2) testing the efficacy of cosmogenic nuclides and 40Ar/39Ar analyses in dating both tills and volcanic ash associated with the ice. Our plan calls for the analysis of a minimum of six cosmogenic depth profiles to determine if and how cryoturbation reworks sublimation tills and assess the average rate of ice sublimation for three debris-covered glaciers. We will model through finite- element analyses at least three buried glaciers and compare flow rates with those based on radiometric dating of surface deposits. Ten ice cores will also be collected for measurement of d18O, dD, ice fabric, ice texture, total gas content/composition. Better understanding of surface processes above buried ice will permit researchers to gain access to a record of atmospheric and climate change that could well cover intervals that predate Quaternary time. The work may also add valuable insight into Martian history. In terms of broader impacts, we have recruited three female PhD students and developed interdisciplinary collaborations among geochemists at Columbia University, planetary geologists at Brown University, geomorphologists at Boston University, and numerical modelers at the University of Maine.
This work will study cosmogenic isotope profiles of rock and sediment in the Dry Valleys of Antarctica to understand their origin. The results will provide important constraints on the history of the East Antarctic Ice Sheet. The near-perfect preservation of volcanic ash and overlying sediments suggests that hyperarid cold conditions have prevailed in the Dry Valleys for over 10 Myr. The survival of these sediments also suggests that warm-based ice has not entered the valley system and ice sheet expansion has been minimal. Other evidence, however, suggests that the Dry Valleys have experienced considerably more sediment erosion than generally believed: 1) the cosmogenic exposure ages of boulders and bedrock in the Valleys all show generally younger ages than volcanic ash deposits used to determine minimum ages of moraines and drifts, 2) there appears to be a discrepancy between the suggested extreme preservation of unconsolidated slope deposits (>10 Myr) and adjacent bedrock that has eroded 2.6-6 m during the same time interval. The fact that the till and moraine exposure ages generally post date the overlying volcanic ash deposits could reflect expansion of continental ice sheet into the Dry Valleys with cold-based ice, thus both preserving the landscape and shielding the surfaces from cosmic radiation. Another plausible explanation of the young cosmogenic exposure ages is erosion of the sediments and gradual exhumation of formerly buried boulders to the surface. Cosmogenic isotope systematics are especially well suited to address these questions. We will measure multiple cosmogenic isotopes in profiles of rock and sediment to determine the minimum exposure ages, the degree of soil stability or mixing, and the shielding history of surfaces by cold based ice. We expect to obtain unambiguous minimum ages for deposits. In addition, we should be able to identify areas disturbed by periglacial activity, constrain the timing of such activity, and account for the patchy preservation of important stratigraphic markers such as volcanic ash. The broader impacts of this project include graduate and undergraduate education, and improving our understanding of the dynamics of Southern Hemisphere climate on timescales of millions of years, which has major implications for understanding the controls and impacts of global climate change.
9909436 <br/>Farley<br/><br/>This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports an investigation of the uplift history of the Dry Valleys segment of the Transantarctic Mountains. The overall goal is to further constrain the exhumation history of the Transantarctic Mountains by using the newly developed apatite (U-Th)/He dating method on samples collected in vertical profiles. This approach, combined with existing apatite fission track information will constrain the rate and patterns of exhumation across the Transantarctic Mountains since their inception as a rift-flank uplift in the early Cenozoic.<br/><br/>This project will complement other projects and build on previous interpretations of the exhumation and tectonic history determined using apatite fission track thermochronology. It will bridge the gap between information on erosion rates determined from fission track thermochronology and from cosmogenic surface exposure dating and integrate the exhumation history of the mountains with their landscape evolution. As such, the results from this project will address an outstanding problem in Antarctic science; namely the stability of the East Antarctic Ice Sheet, and the timing of the transition from a "warm" dynamic ice sheet to a cold polar ice sheet. Highly relevant to this issue is the landscape evolution of the Transantarctic Mountains because many diverse lines of evidence for the rate of landscape evolution have been used to argue for a dynamic ice sheet up until either the Pliocene (the "dynamic" ice sheet model) or the middle Miocene (the "stable" ice sheet model). Understanding the past stability or dynamic fluctuations of the East Antarctic ice sheet with respect to the climate record is, of course, important for understanding how the present ice sheet may respond to global warming.<br/><br/>The specific objective of this project is to determine apatite (U-Th)/He age versus elevation trends for a number of vertical profiles from locations within the Transantarctic Mountain front and across the structural grain of the range. Fission track data already exist for all of these profiles, with apatite fission track ages ranging from 150-30 Ma. The greater precision of the (U-Th)/He technique and the fact it records information at lower temperatures (closure temperature of ~70 degrees Celsius; limits of 40-85 degrees Celsius for the He partial retention zone) will allow examination of the exhumation history of the TAM in more detail from ca 130 Ma to ~20 Ma. Another facet is to examine areas where Cretaceous exhumation is recorded and areas where the fission track profiles indicate periods of thermal and tectonic stability and minimal erosion throughout the Cretaceous. The variation of timing of the onset of more rapid exhumation accompanying uplift and formation of the Transantarctic Mountains in the early Cenozoic will also be examined.
This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.
Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.