[{"awards": "2420258 Prend,Channing", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 07 Jul 2025 00:00:00 GMT", "description": "Antarctic Ice Sheet (AIS) melt is a leading contributor to global sea level rise, which affects coastal communities around the world. Therefore, understanding the mechanisms that control the location and magnitude of melting is crucial to plan for the effects of climate change. The primary heat source causing AIS melt is the ocean, since air temperatures in the Antarctic currently are currently often too cold to melt the glaciers from above. Therefore, ocean currents, which carry heat from the open ocean to the ice sheet, play a key role in determining trends and variability of ice melt in space and time. Previous work on ocean-driven melting of Antarctica have focused on the ocean circulation close to the ice sheets. However, recent modeling studies suggest that changes in ocean currents hundreds of kilometers offshore could have cascading effects on the heat supply to the ice sheet. This project will use observations collected by robotic floats and a climate model to investigate the mechanisms that relate ocean circulation far offshore to ice sheet melt. Characterizing these processes is necessary to improve sea level rise projections.\r\n\r\nThe water mass responsible for driving much of the AIS melt is called Circumpolar Deep Water (CDW) and originates in the open ocean within the Antarctic Circumpolar Current (ACC). While many previous studies have examined cross-shelf heat fluxes, few have analyzed the circumpolar pathways of CDW from the ACC to the continental slope and their influence on AIS mass loss. Importantly, these remote processes control the offshore reservoir of CDW that precedes on-shelf heat transport. This project will quantify the pathways of CDW from its origin in the ACC to the Antarctic continental slope and determine the physical mechanisms that govern the variability of these pathways. Researchers will conduct a series of Lagrangian particle release experiments in a data-assimilating state estimate of the Southern Ocean. Analyzing the trajectories will allow them to statistically constrain regional, seasonal, and interannual variability in the remote pathways of ocean heat transport toward the AIS. The Lagrangian experiments will be complemented by autonomous profiling float data from the West Antarctic. These observations will enable the validation of the model and further probe the physical mechanisms of onshore heat transport. Together, these results will help discern the controls on AIS melting, which has implications for numerous climate feedbacks.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Washington; HEAT FLUX", "locations": "Washington", "north": null, "nsf_funding_programs": "Polar Special Initiatives", "paleo_time": null, "persons": "Prend, Channing", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "OPP-PRF: Remote Pathways of Ocean Heat Transport toward the Antarctic Ice Sheet", "uid": "p0010522", "west": null}, {"awards": "1558448 Girton, James; 1853291 Girton, James", "bounds_geometry": "POLYGON((-70 -58,-69 -58,-68 -58,-67 -58,-66 -58,-65 -58,-64 -58,-63 -58,-62 -58,-61 -58,-60 -58,-60 -58.8,-60 -59.6,-60 -60.4,-60 -61.2,-60 -62,-60 -62.8,-60 -63.6,-60 -64.4,-60 -65.2,-60 -66,-61 -66,-62 -66,-63 -66,-64 -66,-65 -66,-66 -66,-67 -66,-68 -66,-69 -66,-70 -66,-70 -65.2,-70 -64.4,-70 -63.6,-70 -62.8,-70 -62,-70 -61.2,-70 -60.4,-70 -59.6,-70 -58.8,-70 -58))", "dataset_titles": "APL-UW Southern Ocean Wave Glider Data from 2019/20 Mission; Data from 2016 WG launch cruise LMG1612; Data from 2017 WG recovery cruise LMG1703; Data from 2019 WG launch cruise LMG1909; Data from 2020 WG recovery cruise LMG2002; Expedition Data; Expedition data of LMG1612; Expedition Data of LMG1909; LMG2002 Expedtition Data; Wave Glider Data from 2016/17 Mission", "datasets": [{"dataset_uid": "200431", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of LMG1909", "url": "https://www.rvdata.us/search/cruise/LMG1909"}, {"dataset_uid": "200445", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Data from 2019 WG launch cruise LMG1909", "url": "https://www.rvdata.us/search/cruise/LMG1909"}, {"dataset_uid": "200429", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1612", "url": "https://www.rvdata.us/search/cruise/LMG1612"}, {"dataset_uid": "200222", "doi": "10.7284/908802", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG2002 Expedtition Data", "url": "https://www.rvdata.us/search/cruise/LMG2002"}, {"dataset_uid": "200448", "doi": "", "keywords": null, "people": null, "repository": "University of Washington", "science_program": null, "title": "Wave Glider Data from 2016/17 Mission", "url": "http://faculty.washington.edu/jmt3rd/Waveglider/"}, {"dataset_uid": "200447", "doi": "10.7284/908802", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Data from 2020 WG recovery cruise LMG2002", "url": "https://www.rvdata.us/search/cruise/LMG2002"}, {"dataset_uid": "601902", "doi": "10.15784/601902", "keywords": "Antarctica; Cryosphere; Drake Passage; LMG1909; LMG2002; R/v Laurence M. Gould; Temperature; Wave Glider; Wind Speed", "people": "Girton, James", "repository": "USAP-DC", "science_program": null, "title": "APL-UW Southern Ocean Wave Glider Data from 2019/20 Mission", "url": "https://www.usap-dc.org/view/dataset/601902"}, {"dataset_uid": "001365", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1703"}, {"dataset_uid": "200446", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Data from 2017 WG recovery cruise LMG1703", "url": "https://www.rvdata.us/search/cruise/LMG1703"}, {"dataset_uid": "200444", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Data from 2016 WG launch cruise LMG1612", "url": "https://www.rvdata.us/search/cruise/LMG1612"}], "date_created": "Wed, 15 Jan 2025 00:00:00 GMT", "description": "Surface and upper-ocean processes in the Antarctic Circumpolar Current (ACC) play an important role in ocean heat transport, air-sea gas fluxes (such as pCO2) and in sea-ice formation. The net of these in turn modulate global climate, sea level rise and global circulation. This project continues the field development of a surface autonomous vehicle (https://www.liquid-robotics.com/wave-glider/overview/ ) to better measure and study these processes in the remote Southern Ocean, where continuous data is otherwise very difficult to obtain. Mobile autonomous surface vehicles, powered by sunlight and wave action provide a very cost effective manner of solving the problem of obtaining unattended observational coverage in the remote Southern Ocean. The project will support ongoing education and outreach efforts by the PIs including school presentations, visits to science centers and the development of educational materials. The WaveGlider has an established track record of navigating successful spatial surveys and positioned time series measurements in otherwise inhospitable waters and sea-states. The study includes the addition of some new measurement capabilities such as an (upper mixed) layer profiling CTD winch, a high frequency acoustic Doppler turbulence system, and a biogeochemical chlorophyll fluorescence sensor. This augmented instrumentation package will be used for a set of Austral summer season experiments observing ocean-shelf exchange along with frontal air-sea interactions in the vicinity of the West Antarctic Peninsula. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-65 -62)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e CURRENT METERS; IN SITU/LABORATORY INSTRUMENTS \u003e CURRENT/WIND METERS \u003e SONIC ANEMOMETER; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e CAMERA; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS", "is_usap_dc": true, "keywords": "SEA SURFACE TEMPERATURE; WAVE GLIDER; TURBULENCE; SURFACE PRESSURE; OCEAN MIXED LAYER; LMG1703; Palmer Station; SALINITY/DENSITY; SURFACE WINDS; OCEAN CURRENTS; HEAT FLUX; SURFACE AIR TEMPERATURE; HUMIDITY; Drake Passage; R/V NBP; R/V LMG; Antarctic Peninsula; WIND STRESS", "locations": "Drake Passage; Antarctic Peninsula; Palmer Station", "north": -58.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Girton, James; Thomson, Jim", "platforms": "WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES \u003e SURFACE \u003e WAVE GLIDER; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; University of Washington; USAP-DC", "science_programs": null, "south": -66.0, "title": "Wave Glider Observations of Surface Fluxes and Mixed-layer Processes in the Southern Ocean", "uid": "p0010493", "west": -70.0}, {"awards": "2341344 Baker, Bill", "bounds_geometry": null, "dataset_titles": "Orbitrap data from archived marine invertebrates", "datasets": [{"dataset_uid": "601951", "doi": "10.15784/601951", "keywords": "Antarctica; Cryosphere", "people": "Baker, Bill", "repository": "USAP-DC", "science_program": null, "title": "Orbitrap data from archived marine invertebrates", "url": "https://www.usap-dc.org/view/dataset/601951"}], "date_created": "Fri, 15 Sep 2023 00:00:00 GMT", "description": "Non-technical project description Museums of natural history, such as the Smithsonian National Museum of Natural History (NMNH) in Washington, D.C., are repositories for, among other things, biological specimens. Specimens stored at the NMNH were obtained over many decades and across the globe, resulting in what is currently a treasure trove of biological and chemical information. Chemical compounds (metabolites) found in the tissues of, for example, marine invertebrates, can record the organism\u2019s response to a changing environment. This project seeks to establish a strategy for analyzing these compounds in Antarctic marine invertebrates held in the NMNH. These organisms are especially valuable for studies of their metabolites as such information will contribute to our understanding of the history of the polar environment and how organisms are able to adapt to extreme habitats. Further, studies of these rare and difficult to obtain metabolites have broad impacts in biotechnology and human health. Technical description of the project This project seeks to develop a workflow for the analysis of metabolites in archival marine invertebrate specimens held in the Smithsonian National Museum of Natural History (NMNH). Recent advances in mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy, both instrumental as well as analysis platforms, enable the detection and annotation of chemical structures in these otherwise difficult to obtain metabolites. In particular, NMR strategy (Pure Shift NMR) will be implemented to increase sensitivity toward these sample-limited analytes. Further, the workflow will be applied in an analysis of storage methods used by the NMNH with the aim of understanding how best to preserve specimens for future metabolomics analyses. With an optimized workflow established, additional applications to inform our understanding of adaptation and (cryptic) speciation in the extreme habitats found in Antarctica are possible. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; ANIMALS/INVERTEBRATES", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Baker, Bill", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "EAGER: Metabolomics Analysis of Archival Marine Invertebrates", "uid": "p0010435", "west": null}, {"awards": "1744649 Christianson, Knut", "bounds_geometry": "POLYGON((-120 -85.5,-117.5 -85.5,-115 -85.5,-112.5 -85.5,-110 -85.5,-107.5 -85.5,-105 -85.5,-102.5 -85.5,-100 -85.5,-97.5 -85.5,-95 -85.5,-95 -85.62,-95 -85.74,-95 -85.86,-95 -85.98,-95 -86.1,-95 -86.22,-95 -86.34,-95 -86.46000000000001,-95 -86.58,-95 -86.7,-97.5 -86.7,-100 -86.7,-102.5 -86.7,-105 -86.7,-107.5 -86.7,-110 -86.7,-112.5 -86.7,-115 -86.7,-117.5 -86.7,-120 -86.7,-120 -86.58,-120 -86.46000000000001,-120 -86.34,-120 -86.22,-120 -86.1,-120 -85.98,-120 -85.86,-120 -85.74,-120 -85.62,-120 -85.5))", "dataset_titles": "Hercules Dome ApRES Data; Hercules Dome High-Frequency Impulse Ice-Penetrating Radar Data; Hercules Dome Ice-Penetrating Radar Swath Topographies; Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets; ITASE Impulse Radar Hercules Dome to South Pole", "datasets": [{"dataset_uid": "601710", "doi": "10.15784/601710", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Christianson, Knut; Hoffman, Andrew; Hills, Benjamin; O\u0027Connor, Gemma; Horlings, Annika; Holschuh, Nicholas; Christian, John", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Hercules Dome High-Frequency Impulse Ice-Penetrating Radar Data", "url": "https://www.usap-dc.org/view/dataset/601710"}, {"dataset_uid": "601606", "doi": "10.15784/601606", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Christianson, Knut", "repository": "USAP-DC", "science_program": null, "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "url": "https://www.usap-dc.org/view/dataset/601606"}, {"dataset_uid": "601712", "doi": "10.15784/601712", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Hoffman, Andrew; Welch, Brian; Jacobel, Robert; Christianson, Knut", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "ITASE Impulse Radar Hercules Dome to South Pole", "url": "https://www.usap-dc.org/view/dataset/601712"}, {"dataset_uid": "601739", "doi": "10.15784/601739", "keywords": "Antarctica; Apres; Crystal Orientation Fabric; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hercules Dome; Ice Dynamic; Ice Penetrating Radar; Radar Interferometry; Radar Polarimetry", "people": "Steig, Eric J.; Christianson, Knut; Erwin, Emma; Hills, Benjamin; Holschuh, Nicholas; Hoffman, Andrew; Fudge, Tyler J; Horlings, Annika", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Hercules Dome ApRES Data", "url": "https://www.usap-dc.org/view/dataset/601739"}, {"dataset_uid": "601711", "doi": "10.15784/601711", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "people": "Hoffman, Andrew; Holschuh, Nicholas; Paden, John; Christianson, Knut", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Hercules Dome Ice-Penetrating Radar Swath Topographies", "url": "https://www.usap-dc.org/view/dataset/601711"}], "date_created": "Tue, 02 Aug 2022 00:00:00 GMT", "description": "The response of the Antarctic ice sheet to climate change is a central issue in projecting global sea-level rise. While much attention is focused on the ongoing rapid changes at the coastal margin of the West Antarctic Ice Sheet, obtaining records of past ice-sheet and climate change is the only way to constrain how an ice sheet changes over millennial timescales. Whether the West Antarctic Ice Sheet collapsed during the last interglacial period (~130,000 to 116,000 years ago), when temperatures were slightly warmer than today, remains a major unsolved problem in Antarctic glaciology. Hercules Dome is an ice divide located at the intersection of the East Antarctic and West Antarctic ice sheets. It is ideally situated to record the glaciological and climatic effects of changes in the West Antarctic Ice Sheet. This project will establish whether Hercules Dome experienced major changes in flow due to changes in the elevation of the two ice sheets. The project will also ascertain whether Hercules Domes is a suitable site from which to recover climate records from the last interglacial period. These records could be used to determine whether the West Antarctic Ice Sheet collapsed during that period. The project will support two early-career researchers and train students at the University of Washington. Results will be communicated through outreach programs in coordination the Ice Drilling Project Office, the University of Washington\u0027s annual Polar Science Weekend in Seattle, and art-science collaboration. This project will develop a history of ice dynamics at the intersection of the East and West Antarctic ice sheets, and ascertain whether the site is suitable for a deep ice-coring operation. Ice divides provide a unique opportunity to assess the stability of past ice flow. The low deviatoric stresses and non-linearity of ice flow causes an arch (a \"Raymond Bump\") in the internal layers beneath a stable ice divide. This information can be used to determine the duration of steady ice flow. Due to the slow horizontal ice-flow velocities, ice divides also preserve old ice with internal layering that reflects past flow conditions caused by divide migration. Hercules Dome is an ice divide that is well positioned to retain information of past variations in the geometry of both the East and West Antarctic Ice Sheets. This dome is also the most promising location at which to recover an ice core that can be used to determine whether the West Antarctic Ice Sheet collapsed during the last interglacial period. Limited ice-penetrating radar data collected along a previous scientific surface traverse indicate well-preserved englacial stratigraphy and evidence suggestive of a Raymond Bump, but the previous survey was not sufficiently extensive to allow thorough characterization or determination of past changes in ice dynamics. This project will conduct a dedicated survey to map the englacial stratigraphy and subglacial topography as well as basal properties at Hercules Dome. The project will use ground-based ice-penetrating radar to 1) image internal layers and the ice-sheet basal interface, 2) accurately measure englacial attenuation, and 3) determine englacial vertical strain rates. The radar data will be combined with GPS observations for detailed topography and surface velocities and ice-flow modeling to constrain the basal characteristics and the history of past ice flow. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -95.0, "geometry": "POINT(-107.5 -86.1)", "instruments": null, "is_usap_dc": true, "keywords": "West Antarctica; ICE DEPTH/THICKNESS; East Antarctica", "locations": "West Antarctica; East Antarctica", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Christianson, Knut; Hoffman, Andrew; Holschuh, Nicholas", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.7, "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "uid": "p0010359", "west": -120.0}, {"awards": "1643285 Joughin, Ian; 1643174 Padman, Laurence", "bounds_geometry": "POLYGON((-104 -73,-102.2 -73,-100.4 -73,-98.6 -73,-96.8 -73,-95 -73,-93.2 -73,-91.4 -73,-89.6 -73,-87.8 -73,-86 -73,-86 -73.8,-86 -74.6,-86 -75.4,-86 -76.2,-86 -77,-86 -77.8,-86 -78.6,-86 -79.4,-86 -80.2,-86 -81,-87.8 -81,-89.6 -81,-91.4 -81,-93.2 -81,-95 -81,-96.8 -81,-98.6 -81,-100.4 -81,-102.2 -81,-104 -81,-104 -80.2,-104 -79.4,-104 -78.6,-104 -77.8,-104 -77,-104 -76.2,-104 -75.4,-104 -74.6,-104 -73.8,-104 -73))", "dataset_titles": "Beta Version of Plume Model; Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier; icepack; Pine Island Basin Scale Model", "datasets": [{"dataset_uid": "200314", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "icepack", "url": "https://github.com/icepack/icepack"}, {"dataset_uid": "200315", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Pine Island Basin Scale Model", "url": "https://github.com/fastice/icesheetModels"}, {"dataset_uid": "200290", "doi": "http://hdl.handle.net/1773/46687", "keywords": null, "people": null, "repository": "Uni. Washington ResearchWorks Archive", "science_program": null, "title": "Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier", "url": "https://doi.org/10.6069/2MZZ-6B61"}, {"dataset_uid": "200313", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Beta Version of Plume Model", "url": "https://github.com/icepack/plumes"}], "date_created": "Fri, 13 May 2022 00:00:00 GMT", "description": "The West Antarctic Ice Sheet contains enough ice to raise global sea levels by 3-4 meters. Ice-sheet volume falls, and sea level increases, when more ice is lost to the ocean by glacier flow than is replaced by snowfall. Glacier speed is reduced when ice shelves, which are the floating extensions of the ice sheets, are present. Processes that affect ice shelf thickness and extent therefore influence the rates of grounded ice loss and sea-level rise. West Antarctica is currently losing ice, at an accelerating rate, with most loss occurring in the Amundsen Sea region via discharge from Pine Island and Thwaites glaciers. This loss was initiated by increased circulation of relatively warm ocean water beneath these glacier\u0027s ice shelves, causing them to thin by melting. However, this melting also depends on how the changing shape of the ice shelves affects the ocean circulation beneath them and the speeds of the grounded glaciers upstream. Limited understanding of these processes leads to uncertainties in estimates of future ice loss. This interdisciplinary project brings together glaciologists and oceanographers from three US institutions to study the interactions between changing glacier flow, ice shelf shape and extent, and ocean circulation. Data and numerical models will be used to identify the key processes that determine how rapidly this region can shed ice. The project team will train postdocs and graduate students in cutting-edge modeling techniques, and educate the public about Antarctic ice loss through talks, school science fairs, and Seattle Science Center\u0027s annual Polar Science Weekend. The project team will conduct simulations, using a combination of ice-sheet and ocean models, to reduce uncertainties in projected ice loss from Pine Island and Thwaites glaciers by: (i) assessing how ice-shelf melt rates will change as the ice-shelf cavities evolve through melting and grounding-line retreat, and (ii) improving understanding of the sensitivity of sub-shelf melt rates to changes in ocean state on the nearby continental shelf. These studies will reduce uncertainty on ice loss and sea-level rise estimates, and lay the groundwork for development of future fully-coupled ice-sheet/ocean models. The project will first develop high-resolution ice-shelf-cavity circulation models driven by modern observed regional ocean state and validated with estimates of melt derived from satellite observations. Next, an ice-flow model will be used to estimate the future grounding retreat. An iterative process with the ocean-circulation and ice-flow models will then simulate melt rates at each stage of retreat. These results will help assess the validity of the hypothesis that unstable collapse of the Amundsen Sea sector of West Antarctica is underway, which was based on simplified models of melt rate. These models will also provide a better understanding of the sensitivity of melt to regional forcing such as changes in Circumpolar Deep Water temperature and wind-driven changes in thermocline height. Finally, several semi-coupled ice-ocean simulations will help determine the influence of the ocean-circulation driven melt over the next several decades. These simulations will provide a much-improved understanding of the linkages between far-field ocean forcing, cavity circulation and melting, and ice-sheet response.", "east": -86.0, "geometry": "POINT(-95 -77)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER MOTION/ICE SHEET MOTION; USA/NSF; ICE SHEETS; AMD; USAP-DC; MODELS; Amd/Us; Pine Island Glacier", "locations": "Pine Island Glacier", "north": -73.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Joughin, Ian; Dutrieux, Pierre; Padman, Laurence; Springer, Scott", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "GitHub", "repositories": "GitHub; Uni. Washington ResearchWorks Archive", "science_programs": null, "south": -81.0, "title": "Collaborative Research: Modeling ice-ocean interaction for the rapidly evolving ice shelf cavities of Pine Island and Thwaites glaciers, Antarctica ", "uid": "p0010318", "west": -104.0}, {"awards": "2148517 Hancock, Cathrine", "bounds_geometry": "POLYGON((-60 -55,-51 -55,-42 -55,-33 -55,-24 -55,-15 -55,-6 -55,3 -55,12 -55,21 -55,30 -55,30 -57,30 -59,30 -61,30 -63,30 -65,30 -67,30 -69,30 -71,30 -73,30 -75,21 -75,12 -75,3 -75,-6 -75,-15 -75,-24 -75,-33 -75,-42 -75,-51 -75,-60 -75,-60 -73,-60 -71,-60 -69,-60 -67,-60 -65,-60 -63,-60 -61,-60 -59,-60 -57,-60 -55))", "dataset_titles": "Trajectories for APEX floats 9223 and 9224 from acoustic tracking using artoa4argo, Mar 2022-Feb 2023; Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre", "datasets": [{"dataset_uid": "601852", "doi": "10.15784/601852", "keywords": "Antarctica; Continental Slope; Cryosphere; Eddy; Float Trajectory; HAFOS; Weddell Sea", "people": "Hancock, Cathrine; Boebel, Olaf", "repository": "USAP-DC", "science_program": null, "title": "Trajectories for APEX floats 9223 and 9224 from acoustic tracking using artoa4argo, Mar 2022-Feb 2023", "url": "https://www.usap-dc.org/view/dataset/601852"}, {"dataset_uid": "601652", "doi": "10.15784/601652", "keywords": "Antarctica; ANTXXIV/3; Argo Float; Artoa4argo; GPS Data; RAFOS; US Argo Program; Weddell Sea", "people": "Hancock, Cathrine", "repository": "USAP-DC", "science_program": null, "title": "Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre", "url": "https://www.usap-dc.org/view/dataset/601652"}], "date_created": "Fri, 25 Mar 2022 00:00:00 GMT", "description": "The Weddell Gyre is one of the major components of the Southern Ocean circulation system, linking heat and carbon fluxes in the Antarctic Circumpolar Current to the continental margins. Water masses entering the Weddell Gyre are modified as they move in a great circular route around the gyre margin and change through processes involving air-sea-cryosphere interactions as well as through ocean eddies that mix properties across the gyre boundaries. Some of the denser water masses exit the gyre through pathways along the northern boundary, and ultimately ventilate the global deep ocean as Antarctic Bottom Water. While in-situ and satellite observations, as well as computer modeling efforts, provide estimates of the large-scale average flow within the gyre, details of the smaller-scale, or \"mesoscale\" eddy flow remain elusive. The proposed research will quantify mixing due to mesoscale eddies within the Weddell Gyre, as well as the transport of incoming deep water from the northeast, thought to be a result of transient eddies. Since the Weddell Gyre produces source water for about 40% of Antarctic Bottom Water formation, understanding the dynamics in this region helps to identify causes of documented changes in global bottom waters. This in turn, will give insight into how climate change is affecting global oceans, through modification of dense polar waters and Antarctic Bottom Water characteristics. This project aims to track 153 RAFOS-enabled Argo floats in the ice-covered regions of the Weddell Gyre. The resultant tracks along with all available Argo and earlier float data will be used to calculate Eulerian and Lagrangian means and eddy statistics for the Weddell Gyre. The study will link RAFOS tracks with Argo profiles under ice, allowing one to characterize the importance of eddies in water column modification at critical ice-edge boundaries and leads. With RAFOS tracks near the northeastern limit of the gyre, the project will investigate the eddy-driven processes of incoming Circumpolar Deep Water, to understand better the mechanisms and volume fluxes involved. Previous work shows that a large fraction of the mean circulation in the southern and western limits of the gyre, where it contacts the Antarctic continent, occurs in a narrow boundary layer above the slope. The research here will integrate this flow structure into a complete interior and boundary layer mean circulation synthesis. The findings and products from the proposed work will improve the positioning of Argo profiles in the polar regions, which would allow for more accurate climatological maps and derived quantities. Estimates of meso-scale mixing may serve as a foundation for the development of new parameterization schemes employed in climate models, as well as local and global ocean circulation models in polar regions. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 30.0, "geometry": "POINT(-15 -65)", "instruments": null, "is_usap_dc": true, "keywords": "OCEAN CURRENTS; WATER MASSES; BUOYS; USA/NSF; Weddell Sea; AMD; USAP-DC; Amd/Us", "locations": "Weddell Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Hancock, Cathrine; Speer, Kevin", "platforms": "WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e BUOYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0, "title": "Weddell Gyre Mean Circulation and Eddy Statistics from Floats", "uid": "p0010310", "west": -60.0}, {"awards": "2046240 Khan, Alia", "bounds_geometry": "POLYGON((-75 -62,-73.5 -62,-72 -62,-70.5 -62,-69 -62,-67.5 -62,-66 -62,-64.5 -62,-63 -62,-61.5 -62,-60 -62,-60 -62.85,-60 -63.7,-60 -64.55,-60 -65.4,-60 -66.25,-60 -67.1,-60 -67.95,-60 -68.8,-60 -69.65,-60 -70.5,-61.5 -70.5,-63 -70.5,-64.5 -70.5,-66 -70.5,-67.5 -70.5,-69 -70.5,-70.5 -70.5,-72 -70.5,-73.5 -70.5,-75 -70.5,-75 -69.65,-75 -68.8,-75 -67.95,-75 -67.1,-75 -66.25,-75 -65.4,-75 -64.55,-75 -63.7,-75 -62.85,-75 -62))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 10 Sep 2021 00:00:00 GMT", "description": "________________________________________________________________________________________________ Part I: Non-technical Summary The Antarctic Peninsula is one of the most rapidly warming regions on the planet. This 5-yr time-series program will build on an ongoing international collaboration with scientists from the Chilean Antarctic Program to evaluate the role of temperature, light absorbing particles, snow-algae growth, and their radiative forcing effects on snow and ice melt in the Western Antarctic Peninsula. There is strong evidence that these effects may be intensifying due to a warming climate. Rising temperatures can increase the growth rate of coastal snow algae as well as enhance the input of particles from sources such as the long-range transport of black carbon to the Antarctic continent from intensifying Southern Hemisphere wildfire seasons. Particle and algae feedbacks can have immediate local impacts on snow melt and long-term regional impacts on climate because reduced snow cover alters how the Antarctic continent interacts with the rest of the global climate. A variety of ground-based and remote sensing data collected across multiple spatial scales will be used. Ground measurements will be compared to satellite imagery to develop novel computer algorithms to map ice algal bloom effects under changing climates. The project is expected to fundamentally advance knowledge of the spatial and temporal snow algae growing season, which is needed to quantify impacts on regional snow and ice melt. The program also has a strong partnership with the International Association of Antarctic Tour Operators to involve cruise passengers as citizen scientists for sample collection. Antarctic research results will be integrated into undergraduate curricula and research opportunities through studies to LAPs and snow algae in the Pacific Northwest. The PI will recruit and train a diverse pool of students in cryosphere climate related research methods on Mt. Baker in Western Washington. Trained undergraduate will then serve as instructors for a local Snow School that takes middle school students to Mt. Baker to learn about snow science. Resulting datasets from Antarctica and Mt. Baker will be used in University classes to explore regional effects of climate change. Along with enhancing cryosphere-oriented place-based undergraduate field courses in the Pacific Northwest, the PI will recruit and train a diverse pool of undergraduate students to serve as instructors for the Mt. Baker Snow School program. This award will advance our understanding of cryosphere-climate feedbacks, which are likely changing and will continue to evolve in a warming world, while also increasing under-represented student engagement in the polar geosciences. Part 2: Technical Summary Rapid and persistent climate warming in the Western Antarctic Peninsula is likely resulting in intensified snow-algae growth and an extended bloom season in coastal areas. Similarly, deposition of light absorbing particles (LAPs) onto Antarctica cryosphere surfaces, such as black carbon from intensifying Southern Hemisphere wildfire seasons, and dust from the expansion of ice-free regions in the Antarctic Peninsula, may be increasing. The presence of snow algae blooms and LAPs enhance the absorption of solar radiation by snow and ice surfaces. This positive feedback creates a measurable radiative forcing, which can have immediate local and long-term regional impacts on albedo, snow melt and downstream ecosystems. This project will investigate the spatial and temporal distribution of snow algae, black carbon and dust across the Western Antarctica Peninsula region, their response to climate warming, and their role in regional snow and ice melt. Data will be collected across multiple spatial scales from in situ field measurements and sample collection to imagery from ground-based photos and high resolution multi-spectral satellite sensors. Ground measurements will inform development and application of novel algorithms to map algal bloom extent through time using 0.5-3m spatial resolution multi-spectral satellite imagery. Results will be used to improve snow algae parameterization in a new version of the Snow Ice Aerosol Radiation model (SNICARv3) that includes bio-albedo feedbacks, eventually informing models of ice-free area expansion through incorporation of SNICARv3 in the Community Earth System Model. Citizen scientists will be mentored and engaged in the research through an active partnership with the International Association of Antarctic Tour Operators that frequently visits the region. The cruise ship association will facilitate sampling to develop a unique snow algae observing network to validate remote sensing algorithms that map snow algae with high-resolution multi-spectral satellite imagery from space. These time-series will inform instantaneous and interannual radiative forcing calculations to assess impacts of snow algae and LAPs on regional snow melt. Quantifying the spatio-temporal growing season of snow algae and impacts from black carbon and dust will increase our ability to model their impact on snow melt, regional climate warming and ice-free expansion in the Antarctic Peninsula region. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-67.5 -66.25)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Antarctic Peninsula; Amd/Us; AMD; SNOW/ICE CHEMISTRY; USA/NSF; USAP-DC; SNOW", "locations": "Antarctic Peninsula", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Khan, Alia", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -70.5, "title": "CAREER: Coastal Antarctic Snow Algae and Light Absorbing Particles: Snowmelt, Climate and Ecosystem Impacts", "uid": "p0010263", "west": -75.0}, {"awards": "1947094 Sidor, Christian", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "Non-technical Abstract Around 252 million years ago, a major mass extinction wiped out over 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime devoid of a permanent ice cap. Compared to lower latitudes, relatively little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continents more polar location shielded it from the worst of the extinctions effects. As the result of a NSF-sponsored deep field camp in 2017/2018, a remarkable collection of vertebrate fossils was discovered in the rocks of the Shackleton Glacier region. This collection includes the best preserved and most complete materials of fossil amphibians ever recovered from Antarctica, including two previously undescribed species. This grant supports one postdoctoral researcher with expertise in fossil amphibians to describe and interpret the significance of these fossils, including their identification, relationships, and how they fit into the terrestrial ecosystem of Antarctica and other southern hemisphere terrestrial assemblages in light of the major reorganization of post-extinction environments. Historical collections of fossil amphibians will also be reviewed as part of this work. Undergraduate students at the University of Washington will be actively involved as part of this research and learn skills like hard tissue histology and CT data manipulation. Public engagement in Antarctic science will be accomplished at the University of Washington Burke Museum, which is the Washington State museum of natural history and culture. Specifically, a new exhibit on Antarctic amphibians will be developed as part of the paleontology gallery, which sees over 100,000 visitors per year. Technical Abstract This two-year project will examine the evolution of Triassic temnospondyls based on a remarkable collection of fossils recently recovered from the Shackleton Glacier region of Antarctica. Temnospondyls collected from the middle member of the Fremouw Formation are part of the first collection of identifiable tetrapod fossils from this stratigraphic interval. Thorough anatomical description and comparisons of these fossils will add new faunal information and also aid in determining if this horizon is Early or Middle Triassic in age. Exquisitely preserved temnospondyl material from the lower Fremouw Formation will permit more precise identification than previously possible and will provide insights into the earliest stages of their radiation in the extinction recovery interval. Overall, the Principal Investigator and Postdoctoral Researcher will spearhead an effort to revise the systematics of the Antarctic members of Temnospondyli and properly contextualize them in the framework of Triassic tetrapod evolution. The research team will also take advantage of the climate-sensitive nature of fossil amphibians to better understand patterns of seasonality at high-latitudes during the early Mesozoic by subjecting selected fossils to histological analysis. Preliminary data suggest that temnospondyls were exceptionally diverse and highly endemic immediately after the end-Permian extinction, when compared to their distribution before and after this interval. If confirmed, this macroevolutionary pattern could be used to predict the response of modern amphibians to future climate perturbations. Overall, this research will provide new insights into the vertebrate fauna of the Fremouw Formation, as well as shed light on the evolution of terrestrial ecosystems in southern Pangea in the wake of the Permian-Triassic mass extinction. As part of the broader impacts, the research team will help to develop an exhibit featuring some of the best preserved fossils from Antarctica to explain to the public how paleontologists use fossils and rocks to understand past climates like the Triassic \u0027hot-house\u0027 world that lacked permanent ice caps at the poles. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Temnospondyls; MACROFOSSILS; USA/NSF; FIELD SURVEYS; Permian Extinction; Triassic; Amd/Us; USAP-DC; AMD; ANIMALS/VERTEBRATES; Shackleton Glacier", "locations": "Shackleton Glacier", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN", "persons": "Sidor, Christian", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": null, "title": "A non-amniote perspective on the recovery from the end-Permian extinction at high latitudes: paleobiology of Early Triassic temnospondyls from Antarctica", "uid": "p0010217", "west": null}, {"awards": "1851022 Fudge, Tyler; 1851094 Baker, Ian", "bounds_geometry": null, "dataset_titles": "Code for calculating mean gradient for EDC sulfate data; EPICA Dome C Sulfate Data 7-3190m; Forward Diffusion Model used to calculate widening of volcanic layer widths; Volcanic Widths in Dome C Interglacials and Glacials", "datasets": [{"dataset_uid": "601759", "doi": "10.15784/601759", "keywords": "Antarctica", "people": "Severi, Mirko; Fudge, T. J.", "repository": "USAP-DC", "science_program": "COLDEX", "title": "EPICA Dome C Sulfate Data 7-3190m", "url": "https://www.usap-dc.org/view/dataset/601759"}, {"dataset_uid": "601855", "doi": "10.15784/601855", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Volcanic Widths in Dome C Interglacials and Glacials", "url": "https://www.usap-dc.org/view/dataset/601855"}, {"dataset_uid": "601856", "doi": "10.15784/601856", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Code for calculating mean gradient for EDC sulfate data", "url": "https://www.usap-dc.org/view/dataset/601856"}, {"dataset_uid": "601857", "doi": "10.15784/601857", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Forward Diffusion Model used to calculate widening of volcanic layer widths", "url": "https://www.usap-dc.org/view/dataset/601857"}], "date_created": "Mon, 28 Jun 2021 00:00:00 GMT", "description": "The ice of the polar ice sheets is among the purest substances on Earth, yet the small amount of impurities --such as acids-- are important to how the ice flows and what can be learned from ice cores about past climate. The goal of this project is to understand the role of such acids on the deformation of polycrystalline ice by comparing the deformation behavior of pure and sulfuric acid-doped samples. Sulfuric acid was chosen both because of its importance for interpreting past climate and because it can lead to water veins in ice at low temperatures. This work will focus on the location, movement, and impact of acids in polycrystalline ice that are more complex than in single crystals of ice. By deforming samples and performing microstructural characterization, the role of acids on deformation rate, grain evolution, and the movement of the acids themselves, will be assessed. The work will lead to the education of a Ph.D. student at Dartmouth College, introduce undergraduate students to research at both the University of Washington and Dartmouth College. Despite the ubiquitous use of the constitutive relation for ice commonly referred to as \"Glen\u0027s Flow Law\", significant uncertainty exists particularly with regard to the role of impurities and the development of oriented fabrics. The aim of this project is to improve the constitutive relationship for ice by performing deformation tests and microstructural characterization of pure and sulfuric acid-doped ice. The project will focus on sulfuric acid\u0027s impact on ice viscosity, fabric evolution, and diffusivity. Sulfuric acid can have both direct and indirect effects on the mechanical properties of polycrystalline ice. The direct effects change the dislocation velocity and/or density, and the indirect effects change the grain size and fabric. The complexity and interaction of these effects means that it is not possible to understand the effects of sulfuric acid by simply examining ice core specimens. In this project, the team will deform four types of ice: lab-grown ice samples doped with similar-to-natural concentrations of sulfuric acid, lab-grown high-purity ice, layered doped and pure ice, and natural ice from Antarctic ice cores. Deformation will be performed in both uniaxial compression and simple shear. The addition of simple shear tests is critical for relating the laboratory-observed deformation behavior to the behavior of polar ice sheets where the shear strain dominates ice motion in basal ice. After deformation to strains from 5 percent up to 25 percent, the microstructural development will be assessed with methods including a variety of scanning electron microscope techniques, Raman microscopy, synchrotron-based Nano-X-ray fluorescence, and ion chromatography. These analysis techniques will allow the determination of 1) the segregation and movement of impurities, 2) the rate of grain-boundary migration, 3) the number of recrystallized grains; and 4) the full orientation of the ice crystals. The results will enable both microstructural modeling of the effects of sulfuric acid and numerical modeling of diffusion in ice cores. The net result will be a better understanding of ice deformation that improves ice-core interpretation and ice-sheet modeling. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "AMD; Polycrystalline Ice; LABORATORY; Epica Dome C; SNOW/ICE; USA/NSF; USAP-DC; Ice Core; Amd/Us", "locations": "Epica Dome C", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Science and Technology; Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian; Fudge, T. J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Impact of Impurities and Stress State on Polycrystalline Ice Deformation", "uid": "p0010211", "west": null}, {"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. 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.", "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": "1643353 Christianson, Knut; 1643301 Gerbi, Christopher", "bounds_geometry": null, "dataset_titles": "ImpDAR: an impulse radar processor; SeidarT; South Pole Lake ApRES Radar; South Pole Lake GNSS; South Pole Lake: ground-based ice-penetrating radar", "datasets": [{"dataset_uid": "601502", "doi": "10.15784/601502", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GNSS; GPS; GPS Data; South Pole; Subglacial Lakes", "people": "Hills, Benjamin", "repository": "USAP-DC", "science_program": null, "title": "South Pole Lake GNSS", "url": "https://www.usap-dc.org/view/dataset/601502"}, {"dataset_uid": "601503", "doi": "10.15784/601503", "keywords": "Antarctica; Apres; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; South Pole; Subglacial Lakes; Vertical Velocity", "people": "Hills, Benjamin", "repository": "USAP-DC", "science_program": null, "title": "South Pole Lake ApRES Radar", "url": "https://www.usap-dc.org/view/dataset/601503"}, {"dataset_uid": "200244", "doi": " https://zenodo.org/badge/latestdoi/382590632", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "SeidarT", "url": "https://github.com/UMainedynamics/SeidarT"}, {"dataset_uid": "200202", "doi": "http://doi.org/10.5281/zenodo.3833057", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "ImpDAR: an impulse radar processor", "url": "https://www.github.com/dlilien/ImpDAR"}, {"dataset_uid": "200203", "doi": "", "keywords": null, "people": null, "repository": "Uni. Washington ResearchWorks Archive", "science_program": null, "title": "South Pole Lake: ground-based ice-penetrating radar", "url": "http://hdl.handle.net/1773/45293"}], "date_created": "Wed, 17 Feb 2021 00:00:00 GMT", "description": "Gerbi/1643301 This award supports a project to develop software that will allow researchers considering seismic or radar field surveys to test, ahead of time, whether the data they plan to collect will have sufficient resolution to measure the natural variations in the mechanical properties of ice, which determine the response of flowing ice to changing climatic conditions. The mechanical properties of ice depend largely on the temperature and the orientation of the crystals that make up the ice. The most accurate method for measuring ice crystal orientation and temperature is through drilling and direct analysis of an ice core. However, this method is very costly, time-consuming, and limited in spatial coverage. Geophysical techniques, such as seismic and radar, can cover much more area, but we have little knowledge about the practical limitations of these techniques as they relate to calculating mechanical properties. This project addresses that knowledge gap through construction of a computational toolbox that will allow accurate assessment of the ability of geophysical surveys to image crystal orientation and ice temperature. Researchers can then use these tools to adjust the field survey plans to maximize the return on investment. By working to improve the efficiency and effectiveness of future geophysical work related to glacial flow, this proposal will improve scientists? ability to quantify sea-level variations within the larger context of climate change. The project includes building new user-friendly, publicly accessible software and instructional modules. The work will provide training for graduate and undergraduate students, who will play a role in research and develop instructional materials. Ice viscosity, the resistance of ice to flow, exerts significant control over ice velocity. Therefore, mapping ice viscosity is important for understanding the current and future behavior of glaciers and ice sheets. To do so, scientists must determine the temperature and crystal orientation fabric throughout the ice. Seismic and radar techniques can survey large areas quickly, and thus are promising, yet not fully tested, methods to efficiently measure the thermal and mechanical structure of flowing ice. As part of this project, scientists will develop and use a computational framework to quantify the degree to which seismic and radar techniques can resolve the crystal orientation fabric and temperature of streaming ice, and then test how sensitive ice flow is to the attendant uncertainty. To meet these goals, a numerical toolbox will be built which will allow the glacier/ice stream geometry and physical properties (temperature, crystal orientation fabric, density and acidity) to be varied. The toolbox will be capable of both creating synthetic radar and seismic profiles through forward modeling and inverting synthetic profiles to allow evaluation of how well geophysical techniques can image the original thermal and mechanical structure. These simulated radar and seismic data will allow scientists to better quantify the influence of the variability in mechanical properties of the ice on flow velocities and patterns. The results of this work will guide planning for future field campaigns, making them more effective and efficient. This project does not require fieldwork in the Antarctic.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "United States Of America; GLACIERS/ICE SHEETS; USAP-DC; GLACIER MOTION/ICE SHEET MOTION; GLACIER THICKNESS/ICE SHEET THICKNESS; ICE SHEETS; South Pole; USA/NSF; AMD; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; FIELD SURVEYS; Amd/Us", "locations": "South Pole; United States Of America", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Christianson, Knut; Gerbi, Christopher; Campbell, Seth; Vel, Senthil", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "GitHub; Uni. Washington ResearchWorks Archive; USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow", "uid": "p0010160", "west": null}, {"awards": "1744584 Klein, Andrew; 1744570 Galloway, Aaron; 1744550 Amsler, Charles; 1744602 Iken, Katrin", "bounds_geometry": "POLYGON((-70 -61,-69 -61,-68 -61,-67 -61,-66 -61,-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-60 -61.772,-60 -62.544,-60 -63.316,-60 -64.088,-60 -64.86,-60 -65.632,-60 -66.404,-60 -67.176,-60 -67.948,-60 -68.72,-61 -68.72,-62 -68.72,-63 -68.72,-64 -68.72,-65 -68.72,-66 -68.72,-67 -68.72,-68 -68.72,-69 -68.72,-70 -68.72,-70 -67.948,-70 -67.176,-70 -66.404,-70 -65.632,-70 -64.86,-70 -64.088,-70 -63.316,-70 -62.544,-70 -61.772,-70 -61))", "dataset_titles": "Average global horizontal solar irradiance at study sites; Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula; Chemical composition data for Desmarestia menziesii; Chemical composition data for Himantothallus grandifolius; Chemical composition data for Iridaea ; Chemical composition data for Sarcopeltis antarctica ; Computed fetch for project study sites; Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index ; Gridded sea ice concentrations from National Ice Center (NIC) Charts 2014-2019 for Western Antarctic Peninsula ; Initial release of code and data associated with Whippo et al. (2024) Fatty acid profiles and stable isotope composition of Antarctic macroalgae: A baseline for a combined biomarker approach in food web studies.; Landsat Sea Ice/Cloud classifications surrounding project study sites; Latitude and longitude data for project study sites; LMG1904 expedition data; Macroalgal species collected along horizontal transect components ; Modelled Solar Irradiance for Western Antarctic Pennisula; Sea Ice Concentration Timeseries for study sites; Underwater transect videos used for community analyses; Underwater video transect community analysis data; VIIRS KD(490) diffuse attenuation coefficients for study sites", "datasets": [{"dataset_uid": "601639", "doi": "10.15784/601639", "keywords": "Antarctica; Antarctic Peninsula; Biota; Fetch; LMG1904; R/v Laurence M. Gould", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Computed fetch for project study sites", "url": "https://www.usap-dc.org/view/dataset/601639"}, {"dataset_uid": "200402", "doi": "10.5281/zenodo.10524919", "keywords": null, "people": null, "repository": "Zendo", "science_program": null, "title": "Initial release of code and data associated with Whippo et al. (2024) Fatty acid profiles and stable isotope composition of Antarctic macroalgae: A baseline for a combined biomarker approach in food web studies.", "url": "https://zenodo.org/records/10524920"}, {"dataset_uid": "601330", "doi": "10.15784/601330", "keywords": "Antarctica; Antarctic Peninsula; Biota; LMG1904; R/v Laurence M. Gould; Sample Location", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Latitude and longitude data for project study sites", "url": "https://www.usap-dc.org/view/dataset/601330"}, {"dataset_uid": "601610", "doi": "10.15784/601610", "keywords": "Antarctica; Antarctic Peninsula; Benthic Communities; Biota; Macroalgae; Macroinvertebrates; Oceans; Video Transects", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Underwater transect videos used for community analyses", "url": "https://www.usap-dc.org/view/dataset/601610"}, {"dataset_uid": "601619", "doi": "10.15784/601619", "keywords": "Antarctica; Antarctic Peninsula; Benthic Communities; Biota; Macroalgae; Macroinvertebrates; Oceans; Video Transects", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Underwater video transect community analysis data", "url": "https://www.usap-dc.org/view/dataset/601619"}, {"dataset_uid": "601640", "doi": "10.15784/601640", "keywords": "Antarctica; Biota; Diffuse Attenuation Coefficient; LMG1904; R/v Laurence M. Gould; Turbidity", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "VIIRS KD(490) diffuse attenuation coefficients for study sites", "url": "https://www.usap-dc.org/view/dataset/601640"}, {"dataset_uid": "601641", "doi": "10.15784/601641", "keywords": "Antarctica; Average Global Horizontal Solar Irradiance; Biota; LMG1904; R/v Laurence M. Gould", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Average global horizontal solar irradiance at study sites", "url": "https://www.usap-dc.org/view/dataset/601641"}, {"dataset_uid": "601642", "doi": "10.15784/601642", "keywords": "Antarctica; Antarctic Peninsula; Biota; LMG1904; R/v Laurence M. Gould; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Sea Ice Concentration Timeseries for study sites", "url": "https://www.usap-dc.org/view/dataset/601642"}, {"dataset_uid": "601643", "doi": "10.15784/601643", "keywords": "Antarctica; Antarctic Peninsula; LMG1904; National Ice Center Charts; R/v Laurence M. Gould; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Gridded sea ice concentrations from National Ice Center (NIC) Charts 2014-2019 for Western Antarctic Peninsula ", "url": "https://www.usap-dc.org/view/dataset/601643"}, {"dataset_uid": "601649", "doi": "10.15784/601649", "keywords": "Antarctica; Antarctic Peninsula; LMG1904; National Ice Center Charts; Sea Ice Concentration", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index ", "url": "https://www.usap-dc.org/view/dataset/601649"}, {"dataset_uid": "601651", "doi": "10.15784/601651", "keywords": "Antarctica; Antarctic Peninsula; Biota; GIS; GIS Data; LMG1904; R/v Laurence M. Gould; Solar Radiation", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Modelled Solar Irradiance for Western Antarctic Pennisula", "url": "https://www.usap-dc.org/view/dataset/601651"}, {"dataset_uid": "601653", "doi": "10.15784/601653", "keywords": "Antarctica; Antarctic Peninsula; Biota; Carbon; Carbon Isotopes; LMG1904; Nitrogen Isotopes; Oceans", "people": "Iken, Katrin", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601653"}, {"dataset_uid": "601654", "doi": "10.15784/601654", "keywords": "Antarctica; Antarctic Peninsula; GIS; LANDSAT; LMG1904; Remote Sensing; R/v Laurence M. Gould", "people": "Klein, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Landsat Sea Ice/Cloud classifications surrounding project study sites", "url": "https://www.usap-dc.org/view/dataset/601654"}, {"dataset_uid": "601725", "doi": "10.15784/601725", "keywords": "Antarctica; Antarctic Peninsula", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Macroalgal species collected along horizontal transect components ", "url": "https://www.usap-dc.org/view/dataset/601725"}, {"dataset_uid": "601882", "doi": "10.15784/601882", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Desmarestia menziesii", "url": "https://www.usap-dc.org/view/dataset/601882"}, {"dataset_uid": "601883", "doi": "10.15784/601883", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Himantothallus grandifolius", "url": "https://www.usap-dc.org/view/dataset/601883"}, {"dataset_uid": "601884", "doi": "10.15784/601884", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Iridaea ", "url": "https://www.usap-dc.org/view/dataset/601884"}, {"dataset_uid": "601885", "doi": "10.15784/601885", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Macroalgae", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Chemical composition data for Sarcopeltis antarctica ", "url": "https://www.usap-dc.org/view/dataset/601885"}, {"dataset_uid": "200147", "doi": "10.7284/908260", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG1904 expedition data", "url": "https://www.rvdata.us/search/cruise/LMG1904"}], "date_created": "Thu, 04 Jun 2020 00:00:00 GMT", "description": "The western Antarctic Peninsula has become a model for understanding cold water communities and how they may be changing in Antarctica and elsewhere. Brown macroalgae (seaweeds) form extensive undersea forests in the northern portion of this region where they play a key role in providing both physical structure and a food (carbon) source for shallow water communities. Yet between Anvers Island (64 degrees S latitude) and Adelaide Island (67 S latitude) these macroalgae become markedly less abundant and diverse. This is probably because the habitat to the south is covered by more sea ice for a longer period, and the sea ice reduces the amount of light that reaches the algae. The reduced macroalgal cover undoubtedly impacts other organisms in the food web, but the ways in which it alters sea-floor community processes and organization is unknown. This project will quantitatively document the macroalgal communities at multiple sites between Anvers and Adelaide Islands using a combination of SCUBA diving, video surveys, and algal collections. Sea ice cover, light levels, and other environmental parameters on community structure will be modelled to determine which factors have the largest influence. Impacts on community structure, food webs, and carbon flow will be assessed through a mixture of SCUBA diving and video surveys. Broader impacts include the training of graduate students and a postdoctoral researcher, as well as numerous informal public education activities including lectures, presentations to K-12 groups, and a variety of social media-based outreach. Macroalgal communities are more abundance and diverse to the north along the Western Antarctic Peninsula, perhaps due to the greater light availability that is associated with shorter period of sea-ice cover. This project will determine the causes and community level consequence of this variation in algal community structure. First, satellite data on sea ice extent and water turbidity will be used to select study sites between 64 S and 69 S where the extent of annual sea ice cover is the primary factor influencing subsurface light levels. Then, variations in macroalgal cover across these study sites will be determined by video line-transect surveys conducted by SCUBA divers. The health, growth, and physiological status of species found at the different sites will be determined by quadrat sampling. The relative importance of macroalgal-derived carbon to the common invertebrate consumers in the foodweb will be assessed with stable isotope and fatty acid biomarker techniques. This will reveal how variation in macroalgal abundance and species composition across the sea ice cover gradient impacts sea floor community composition and carbon flow throughout the food web. In combination, this work will facilitate predictions of how the ongoing reductions in extent and duration of sea ice cover that is occurring in the region as a result of global climate change will impact the structure of nearshore benthic communities. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -60.0, "geometry": "POINT(-65 -64.86)", "instruments": null, "is_usap_dc": true, "keywords": "COASTAL; R/V LMG; MACROALGAE (SEAWEEDS); BENTHIC; USAP-DC; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Amsler, Charles; McClintock, James; Iken, Katrin; Galloway, Aaron; Klein, Andrew", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "USAP-DC", "repositories": "R2R; USAP-DC; Zendo", "science_programs": null, "south": -68.72, "title": "Collaborative Research: Sea ice as a driver of Antarctic benthic macroalgal community composition and nearshore trophic connectivity", "uid": "p0010104", "west": -70.0}, {"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 meter/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. Broader impacts: 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.", "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": "Sletten, Ronald S.; Toner, Jonathan; 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. 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.", "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": "1443105 Steig, Eric", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core; South Pole high resolution ice core water stable isotope record for dD, d18O; South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt and Major Ions; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601429", "doi": "10.15784/601429", "keywords": "Antarctica; Climate; Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hydrogen; Ice; Ice Core; Ice Core Chemistry; Oxygen; Paleoclimate; Snow/ice; Snow/Ice; South Pole; Stable Isotopes", "people": "Morris, Valerie; Kahle, Emma; White, James; Schauer, Andrew; Steig, Eric J.; Vaughn, Bruce; Jones, Tyler R.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core", "url": "https://www.usap-dc.org/view/dataset/601429"}, {"dataset_uid": "601850", "doi": "10.15784/601850", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601850"}, {"dataset_uid": "601239", "doi": "10.15784/601239", "keywords": "Antarctica; Cavity Ring Down Spectrometers; Delta 18O; Delta Deuterium; Deuterium Isotopes; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Oxygen Isotope; Snow/ice; Snow/Ice; Stable Isotopes", "people": "Kahle, Emma; Jones, Tyler R.; Schauer, Andrew; Vaughn, Bruce; Morris, Valerie; White, James; Steig, Eric J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole high resolution ice core water stable isotope record for dD, d18O", "url": "https://www.usap-dc.org/view/dataset/601239"}, {"dataset_uid": "601851", "doi": "10.15784/601851", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Sea Salt and Major Ions", "url": "https://www.usap-dc.org/view/dataset/601851"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "Buizert, Christo; White, James; Epifanio, Jenna; Waddington, Edwin D.; Conway, Howard; Stevens, Max; Schauer, Andrew; Vaughn, Bruce; Morris, Valerie; Koutnik, Michelle; Fudge, T. J.; Jones, Tyler R.; Steig, Eric J.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}], "date_created": "Sun, 17 Nov 2019 00:00:00 GMT", "description": "This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible. This project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "SPICEcore; D18O; LABORATORY; OXYGEN ISOTOPE ANALYSIS; Oxygen Isotope; South Pole; USAP-DC; GLACIERS/ICE SHEETS; Antarctica; AMD; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Steig, Eric J.; White, James", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole", "uid": "p0010065", "west": 0.0}, {"awards": "1142646 Twickler, Mark; 1142517 Aydin, Murat; 1141839 Steig, Eric", "bounds_geometry": "POINT(90 -90)", "dataset_titles": "South Pole Ice Core Holocene Major Ion Dataset; South Pole Ice Core Sea Salt and Major Ions; South Pole ice core (SPC14) discrete methane data; South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth; SP19 Gas Chronology; Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "datasets": [{"dataset_uid": "601851", "doi": "10.15784/601851", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Sea Salt and Major Ions", "url": "https://www.usap-dc.org/view/dataset/601851"}, {"dataset_uid": "601850", "doi": "10.15784/601850", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "people": "Winski, Dominic A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Holocene Major Ion Dataset", "url": "https://www.usap-dc.org/view/dataset/601850"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601221", "doi": "10.15784/601221", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Data; Ice Core Depth; Ice Core Records; Snow/ice; Snow/Ice; SPICEcore", "people": "Fegyveresi, John; Casey, Kimberly A.; Aydin, Murat; Souney, Joseph Jr.; Nunn, Richard; Hargreaves, Geoff; Fudge, T. J.; Nicewonger, Melinda R.; Kahle, Emma; Steig, Eric J.; Twickler, Mark", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth", "url": "https://www.usap-dc.org/view/dataset/601221"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Winski, Dominic A.; Severinghaus, Jeffrey P.; Epifanio, Jenna; Brook, Edward J.; Buizert, Christo; Kreutz, Karl; Aydin, Murat; Edwards, Jon S.; Sowers, Todd A.; Kahle, Emma; Steig, Eric J.; Osterberg, Erich; Fudge, T. J.; Hood, Ekaterina; Kalk, Michael; Ferris, David G.; Kennedy, Joshua A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601396", "doi": "10.15784/601396", "keywords": "Accumulation; Antarctica; Diffusion Length; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Dynamic; Layer Thinning; Oxygen Isotope; South Pole; SPICEcore; Temperature", "people": "Buizert, Christo; White, James; Epifanio, Jenna; Waddington, Edwin D.; Conway, Howard; Stevens, Max; Schauer, Andrew; Vaughn, Bruce; Morris, Valerie; Koutnik, Michelle; Fudge, T. J.; Jones, Tyler R.; Steig, Eric J.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)", "url": "https://www.usap-dc.org/view/dataset/601396"}], "date_created": "Wed, 30 Oct 2019 00:00:00 GMT", "description": "1142517/Saltzman This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.", "east": 90.0, "geometry": "POINT(90 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; Amd/Us; Antarctica; ANALYTICAL LAB; USA/NSF; AMD; South Pole; ICE CORE RECORDS; FIELD INVESTIGATION; Ice Core", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Twickler, Mark; Souney, Joseph Jr.; Aydin, Murat; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: A 1500m Ice Core from South Pole", "uid": "p0010060", "west": 90.0}, {"awards": "1341728 Stone, John", "bounds_geometry": "POLYGON((-86.3 -81,-86.17 -81,-86.04 -81,-85.91 -81,-85.78 -81,-85.65 -81,-85.52 -81,-85.39 -81,-85.26 -81,-85.13 -81,-85 -81,-85 -81.03,-85 -81.06,-85 -81.09,-85 -81.12,-85 -81.15,-85 -81.18,-85 -81.21,-85 -81.24,-85 -81.27,-85 -81.3,-85.13 -81.3,-85.26 -81.3,-85.39 -81.3,-85.52 -81.3,-85.65 -81.3,-85.78 -81.3,-85.91 -81.3,-86.04 -81.3,-86.17 -81.3,-86.3 -81.3,-86.3 -81.27,-86.3 -81.24,-86.3 -81.21,-86.3 -81.18,-86.3 -81.15,-86.3 -81.12,-86.3 -81.09,-86.3 -81.06,-86.3 -81.03,-86.3 -81))", "dataset_titles": "Cosmogenic nuclide data, Harter Nunatak; Cosmogenic nuclide data, John Nunatak; Cosmogenic nuclide data, Mt Axtell; Cosmogenic nuclide data, Mt Goodwin; Cosmogenic nuclide data, Mt Tidd; Cosmogenic nuclide data, Mt Turcotte; Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data", "datasets": [{"dataset_uid": "200079", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Harter Nunatak", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601214", "doi": "10.15784/601214", "keywords": "Aluminum-26; Antarctica; Be-10; Bedrock Core; Beryllium-10; Chemistry:rock; Chemistry:Rock; Cosmogenic; Cosmogenic Dating; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope Data; Pirrit Hills; Rocks; Solid Earth; Subglacial Bedrock", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data", "url": "https://www.usap-dc.org/view/dataset/601214"}, {"dataset_uid": "200078", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Goodwin", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200077", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Turcotte", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200076", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Tidd", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200080", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, John Nunatak", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200075", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Cosmogenic nuclide data, Mt Axtell", "url": "https://version2.ice-d.org/antarctica/nsf/"}], "date_created": "Tue, 08 Oct 2019 00:00:00 GMT", "description": "Stone/1341728 This award supports a project to determine if the West Antarctic Ice Sheet (WAIS) has thinned and collapsed in the past and if so, when did this occur. This topic is of interest to geologists who have long been studying the history and behavior of ice sheets (including the WAIS) in order to determine what climatic conditions allow an ice sheet to survive and what conditions have caused them to collapse in the past. The bulk of this research has focused on the last ice age, when climate conditions were far colder than the present; this project will focus on the response of ice sheets to warmer climates in the past. A new and potentially transformative approach that uses the analysis of atoms transformed by cosmic-rays in bedrock beneath the WAIS will allow a definitive test for ice free conditions in the past. This is because the cosmic rays capable of producing the necessary reactions can penetrate only a few meters through glacier ice. Therefore, if they are detected in samples from hundreds of meters below the current ice sheet surface this would provide definitive proof of mostly ice-free conditions in the past. The concentrations of different cosmic ray products in cores from different depths will help answer the question of how frequently bedrock has been exposed, how much the ice sheet has thinned, and which time periods in the past produced climatic conditions capable of making the ice sheet unstable. Short bedrock cores beneath the ice sheet near the Pirrit Hills in West Antarctica will be collected using a new agile sub-ice geological drill (capable of drilling up to 200 meters beneath the ice surface) that is being developed by the Ice Drilling Program Office (IDPO) to support this and other projects. Favorable drilling sites have already been identified based on prior reconnaissance mapping, sample analysis and radar surveys of the ice-sheet bed. The cores collected in this study will be analyzed for cosmic-ray-produced isotopes of different elements with a range of half-lives from 5700 yr (C-14) to 1.4 Myr (Be-10), as well as stable Ne-21. The presence or absence of these isotopes will provide a definitive test of whether bedrock surfaces were ice-free in the past and due to their different half-lives, ratios of the isotopes will place constraints on the age, frequency and duration of past exposure episodes. Results from bedrock surfaces at different depths will indicate the degree of past ice-sheet thinning. The aim is to tie evidence of deglaciation in the past to specific periods of warmer climate and thus to gauge the ice sheet\u0027s response to known climate conditions. This project addresses the broad question of ice-sheet sensitivity to climate warming, which previously has been largely determined indirectly from sea-level records. In contrast, this project will provide direct measurements that provide evidence of ice-sheet thinning in West Antarctica. Results from this work will help to identify the climatic factors and thresholds capable of endangering the WAIS in future. The project will make a significant contribution to the ongoing study of climate change, ice-sheet melting and associated sea-level rise. This project has field work in Antarctica.", "east": -85.0, "geometry": "POINT(-85.65 -81.15)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "DEPTH AT SPECIFIC AGES; USAP-DC; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -81.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "ICE-D", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -81.3, "title": "EXPROBE-WAIS: Exposed Rock Beneath the West Antarctic Ice Sheet, A Test for Interglacial Ice Sheet Collapse", "uid": "p0010057", "west": -86.3}, {"awards": "1443248 Hall, Brenda; 1443346 Stone, John", "bounds_geometry": "POLYGON((-174 -84.2,-172.4 -84.2,-170.8 -84.2,-169.2 -84.2,-167.6 -84.2,-166 -84.2,-164.4 -84.2,-162.8 -84.2,-161.2 -84.2,-159.6 -84.2,-158 -84.2,-158 -84.36,-158 -84.52,-158 -84.68,-158 -84.84,-158 -85,-158 -85.16,-158 -85.32,-158 -85.48,-158 -85.64,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.64,-174 -85.48,-174 -85.32,-174 -85.16,-174 -85,-174 -84.84,-174 -84.68,-174 -84.52,-174 -84.36,-174 -84.2))", "dataset_titles": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast; Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN; Ice-D Antarctic Cosmogenic Nuclide database - site MAASON; Liv and Amundsen Glacier Radiocarbon Data", "datasets": [{"dataset_uid": "601226", "doi": "10.15784/601226", "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic; Cosmogenic Dating; Cosmogenic Radionuclides; Deglaciation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Liv Glacier; Rocks; Ross Ice Sheet; Surface Exposure Dates; Transantarctic Mountains", "people": "Stone, John", "repository": "USAP-DC", "science_program": null, "title": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast", "url": "https://www.usap-dc.org/view/dataset/601226"}, {"dataset_uid": "200087", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Ice-D Antarctic Cosmogenic Nuclide database - site MAASON", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "200088", "doi": "", "keywords": null, "people": null, "repository": "ICE-D", "science_program": null, "title": "Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN", "url": "https://version2.ice-d.org/antarctica/nsf/"}, {"dataset_uid": "601208", "doi": "10.15784/601208", "keywords": "Antarctica; Carbon; Glaciology; Holocene; Radiocarbon; Ross Embayment; Ross Sea; Transantarctic Mountains", "people": "Hall, Brenda", "repository": "USAP-DC", "science_program": null, "title": "Liv and Amundsen Glacier Radiocarbon Data", "url": "https://www.usap-dc.org/view/dataset/601208"}], "date_created": "Thu, 05 Sep 2019 00:00:00 GMT", "description": "The response of the Antarctic Ice Sheet to future climatic changes is recognized as the greatest uncertainty in projections of future sea level. An understanding of past ice fluctuations affords insight into ice-sheet response to climate and sea-level change and thus is critical for improving sea-level predictions. This project will examine deglaciation of the southern Ross Sea over the past few thousand years to document oscillations in Antarctic ice volume during a period of relatively stable climate and sea level. We will help quantify changes in ice volume, improve understanding of the ice dynamics responsible, and examine the implications for future sea-level change. The project will train future scientists through participation of graduate students, as well as undergraduates who will develop research projects in our laboratories. Previous research indicates rapid Ross Sea deglaciation as far south as Beardmore Glacier early in the Holocene epoch (which began approximately 11,700 years before present), followed by more gradual recession. However, deglaciation in the later half of the Holocene remains poorly constrained, with no chronological control on grounding-line migration between Beardmore and Scott Glaciers. Thus, we do not know if mid-Holocene recession drove the grounding line rapidly back to its present position at Scott Glacier, or if the ice sheet withdrew gradually in the absence of significant climate forcing or eustatic sea level change. The latter possibility raises concerns for future stability of the Ross Sea grounding line. To address this question, we will map and date glacial deposits on coastal mountains that constrain the thinning history of Liv and Amundsen Glaciers. By extending our chronology down to the level of floating ice at the mouths of these glaciers, we will date their thinning history from glacial maximum to present, as well as migration of the Ross Sea grounding line southwards along the Transantarctic Mountains. High-resolution dating will come from Beryllium-10 surface-exposure ages of erratics collected along elevation transects, as well as Carbon-14 dates of algae within shorelines from former ice-dammed ponds. Sites have been chosen specifically to allow close comparison of these two dating methods, which will afford constraints on Antarctic Beryllium-10 production rates.", "east": -158.0, "geometry": "POINT(-166 -85)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "GLACIERS/ICE SHEETS; NOT APPLICABLE; Antarctica; ICE SHEETS; USAP-DC", "locations": "Antarctica", "north": -84.2, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Hall, Brenda; Stone, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "ICE-D; USAP-DC", "science_programs": null, "south": -85.8, "title": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment", "uid": "p0010053", "west": -174.0}, {"awards": "1744645 Young, Jodi", "bounds_geometry": "POLYGON((-64.4 -64.2,-64.38 -64.2,-64.36 -64.2,-64.34 -64.2,-64.32 -64.2,-64.3 -64.2,-64.28 -64.2,-64.26 -64.2,-64.24 -64.2,-64.22 -64.2,-64.2 -64.2,-64.2 -64.26,-64.2 -64.32,-64.2 -64.38,-64.2 -64.44,-64.2 -64.5,-64.2 -64.56,-64.2 -64.62,-64.2 -64.68,-64.2 -64.74,-64.2 -64.8,-64.22 -64.8,-64.24 -64.8,-64.26 -64.8,-64.28 -64.8,-64.3 -64.8,-64.32 -64.8,-64.34 -64.8,-64.36 -64.8,-64.38 -64.8,-64.4 -64.8,-64.4 -64.74,-64.4 -64.68,-64.4 -64.62,-64.4 -64.56,-64.4 -64.5,-64.4 -64.44,-64.4 -64.38,-64.4 -64.32,-64.4 -64.26,-64.4 -64.2))", "dataset_titles": "Dataset: Particulate Organic Carbon and Particulate Nitrogen; Dataset: Photosynthetic Pigments; Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume; Sea-ice diatom compatible solute shifts", "datasets": [{"dataset_uid": "200322", "doi": "10.21228/M84386", "keywords": null, "people": null, "repository": "Metabolomics workbench", "science_program": null, "title": "Sea-ice diatom compatible solute shifts", "url": "https://www.metabolomicsworkbench.org/data/DRCCMetadata.php?Mode=Study\u0026StudyID=ST001393"}, {"dataset_uid": "200376", "doi": "10.26008/1912/bco-dmo.913566.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Particulate Organic Carbon and Particulate Nitrogen", "url": "https://www.bco-dmo.org/dataset/913566"}, {"dataset_uid": "200377", "doi": "10.26008/1912/bco-dmo.913222.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Photosynthetic Pigments", "url": "https://www.bco-dmo.org/dataset/913222"}, {"dataset_uid": "200378", "doi": "10.26008/1912/bco-dmo.913655.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume", "url": "https://www.bco-dmo.org/dataset/913655"}], "date_created": "Tue, 23 Jul 2019 00:00:00 GMT", "description": "Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. There is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -64.2, "geometry": "POINT(-64.3 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; SHIPS; DIATOMS; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -64.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Young, Jodi; Deming, Jody", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "Metabolomics workbench", "repositories": "BCO-DMO; Metabolomics workbench", "science_programs": null, "south": -64.8, "title": "Spring Blooms of Sea Ice Algae Along the Western Antarctic Peninsula: Effects of Warming and Freshening on Cell Physiology and Biogeochemical Cycles.", "uid": "p0010039", "west": -64.4}, {"awards": "1443680 Smith, Craig; 1443733 Winsor, Peter; 1443705 Vernet, Maria", "bounds_geometry": "POLYGON((-66 -64,-65.6 -64,-65.2 -64,-64.8 -64,-64.4 -64,-64 -64,-63.6 -64,-63.2 -64,-62.8 -64,-62.4 -64,-62 -64,-62 -64.1,-62 -64.2,-62 -64.3,-62 -64.4,-62 -64.5,-62 -64.6,-62 -64.7,-62 -64.8,-62 -64.9,-62 -65,-62.4 -65,-62.8 -65,-63.2 -65,-63.6 -65,-64 -65,-64.4 -65,-64.8 -65,-65.2 -65,-65.6 -65,-66 -65,-66 -64.9,-66 -64.8,-66 -64.7,-66 -64.6,-66 -64.5,-66 -64.4,-66 -64.3,-66 -64.2,-66 -64.1,-66 -64))", "dataset_titles": "Andvord Bay Glacier Timelapse; Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603); Expedition Data; Expedition data of LMG1702; FjordEco Phytoplankton Ecology Dataset in Andvord Bay ; Fjord-Eco Sediment OrgC OrgN Data - Craig Smith; LMG1510 Expedition data; NBP1603 Expedition data; Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf", "datasets": [{"dataset_uid": "002733", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1702", "url": "https://www.rvdata.us/search/cruise/LMG1702"}, {"dataset_uid": "601111", "doi": "10.15784/601111", "keywords": "Antarctica; Antarctic Peninsula; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iceberg; Photo; Photo/video; Photo/Video", "people": "Winsor, Peter; Truffer, Martin", "repository": "USAP-DC", "science_program": "FjordEco", "title": "Andvord Bay Glacier Timelapse", "url": "https://www.usap-dc.org/view/dataset/601111"}, {"dataset_uid": "001366", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1702"}, {"dataset_uid": "601236", "doi": "10.15784/601236", "keywords": "Abundance; Andvord Bay; Antarctica; Antarctic Peninsula; Biota; Fjord; LMG1510; Marine Sediments; Oceans; Polychaete; Polychaete Family Richness; R/v Laurence M. Gould; Sediment Core Data; Sediment Macrofauna", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "FjordEco", "title": "Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf", "url": "https://www.usap-dc.org/view/dataset/601236"}, {"dataset_uid": "601193", "doi": "10.15784/601193", "keywords": "Antarctica; Geochronology; Grain Size; LMG1510; NBP1603; Sediment; Sediment Core Data", "people": "Homolka, Khadijah; Nittrouer, Charles; Eidam, Emily; Smith, Craig", "repository": "USAP-DC", "science_program": null, "title": "Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)", "url": "https://www.usap-dc.org/view/dataset/601193"}, {"dataset_uid": "601158", "doi": "10.15784/601158", "keywords": "Antarctica; Antarctic Peninsula; Biota; Ecology; Fjord; Phytoplankton", "people": "Pan, B. Jack; Forsch, Kiefer; Vernet, Maria; Manck, Lauren", "repository": "USAP-DC", "science_program": "FjordEco", "title": "FjordEco Phytoplankton Ecology Dataset in Andvord Bay ", "url": "https://www.usap-dc.org/view/dataset/601158"}, {"dataset_uid": "601157", "doi": "10.15784/601157", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Snow/ice; Snow/Ice", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "FjordEco", "title": "Fjord-Eco Sediment OrgC OrgN Data - Craig Smith", "url": "https://www.usap-dc.org/view/dataset/601157"}, {"dataset_uid": "200039", "doi": "10.7284/907205", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1603 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1603"}, {"dataset_uid": "200040", "doi": "10.7284/907085", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "LMG1510 Expedition data", "url": "https://www.rvdata.us/search/cruise/LMG1510"}, {"dataset_uid": "000402", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1702"}], "date_created": "Wed, 13 Feb 2019 00:00:00 GMT", "description": "Marine communities along the western Antarctic Peninsula are highly productive ecosystems which support a diverse assemblage of charismatic animals such as penguins, seals, and whales as well as commercial fisheries such as that on Antarctic krill. Fjords (long, narrow, deep inlets of the sea between high cliffs) along the central coast of the Peninsula appear to be intense, potentially climate sensitive, hotspots of biological production and biodiversity, yet the structure and dynamics of these fjord ecosystems are very poorly understood. Because of this intense biological activity and the charismatic fauna it supports, these fjords are also major destinations for a large Antarctic tourism industry. This project is an integrated field and modeling program to evaluate physical oceanographic processes, glacial inputs, water column community dynamics, and seafloor bottom community structure and function in these important yet little understood fjord systems. These Antarctic fjords have characteristics that are substantially different from well-studied Arctic fjords, likely yielding much different responses to climate warming. This project will provide major new insights into the dynamics and climate sensitivity of Antarctic fjord ecosystems, highlighting contrasts with Arctic sub-polar fjords, and potentially transforming our understanding of the ecological role of fjords in the rapidly warming west Antarctic coastal marine landscape. The project will also further the NSF goal of training new generations of scientists, providing scientific training for undergraduate, graduate, and postdoctoral students. This includes the unique educational opportunity for undergraduates to participate in research cruises in Antarctica and the development of a novel summer graduate course on fjord ecosystems. Internet based outreach activities will be enhanced and extended by the participation of a professional photographer who will produce magazine articles, websites, radio broadcasts, and other forms of public outreach on the fascinating Antarctic ecosystem. This project will involve a 15-month field program to test mechanistic hypotheses concerning oceanographic and glaciological forcing, and phytoplankton and benthic community response in the Antarctic fjords. Those efforts will be followed by a coupled physical/biological modeling effort to evaluate the drivers of biogeochemical cycles in the fjords and to explore their potential sensitivity to enhanced meltwater and sediment inputs. Fieldwork over two oceanographic cruises will utilize moorings, weather stations, and glacial, sea-ice and seafloor time-lapse cameras to obtain an integrated view of fjord ecosystem processes. The field team will also make multiple shipboard measurements and will use towed and autonomous underwater vehicles to intensively evaluate fjord ecosystem structure and function during spring/summer and autumn seasons. These integrated field and modeling studies are expected to elucidate fundamental properties of water column and sea bottom ecosystem structure and function in the fjords, and to identify key physical-chemical-glaciological forcing in these rapidly warming ecosystems.", "east": -62.0, "geometry": "POINT(-64 -64.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN CURRENTS; Bellingshausen Sea; LMG1702; COMMUNITY DYNAMICS; FJORDS; R/V LMG; MARINE ECOSYSTEMS; USAP-DC; ECOSYSTEM FUNCTIONS; ANIMALS/INVERTEBRATES; SEDIMENTATION; NOT APPLICABLE; BENTHIC", "locations": "Bellingshausen Sea", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Winsor, Peter; Truffer, Martin; Smith, Craig; Powell, Brian; Merrifield, Mark; Vernet, Maria; Kohut, Josh", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": "FjordEco", "south": -65.0, "title": "Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)", "uid": "p0010010", "west": -66.0}, {"awards": "1141916 Aster, Richard", "bounds_geometry": null, "dataset_titles": "Dynamic Response of the Ross Ice Shelf to Ocean Waves and Structure and Dynamics of the Ross Sea", "datasets": [{"dataset_uid": "002573", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "Dynamic Response of the Ross Ice Shelf to Ocean Waves and Structure and Dynamics of the Ross Sea", "url": "http://www.iris.washington.edu/mda/XH?timewindow=2014-2017"}], "date_created": "Mon, 22 Oct 2018 00:00:00 GMT", "description": "Intellectual Merit: The PIs propose to establish an ice shelf network of 18 broadband seismographs deployed for two years to obtain high-resolution, mantle-scale images of Earth structure underlying the Ross Sea Embayment. Prior marine geophysical work provides good crustal velocity models for the region seaward of the ice shelf but mantle structure is constrained by only low-resolution images due to the lack of prior seismic deployments. The proposed stations would be established between Ross Island and Marie Byrd Land. These stations would fill a major geological gap within this extensional continental province and would link data sets collected in the Transantarctic Mountain transition/Plateau region (TAMSEIS) and in West Antarctica (POLENET) to improve resolution of mantle features beneath Antarctica. The proposed deployment would allow the PIs to collect seismic data without the expense, logistical complexity, and iceberg hazards associated with ocean bottom seismograph deployments. Tomographic models developed from the proposed data will be used to choose between competing models for the dynamics of the Ross Sea. In particular, the PIs will investigate whether a broad region of hot mantle, including the Eastern Ross Sea, indicates distributed recent tectonic activity, which would call into question models proposing that Eastern Ross extension ceased during the Mesozoic. These data will also allow the PIs to investigate the deeper earth structure to evaluate the possible role of mantle plumes and/or small-scale convection in driving regional volcanism and tectonism across the region. Broader impacts: Data from this deployment will be of broad interdisciplinary use. This project will support three graduate and two undergraduate students. At least one student will be an underrepresented minority student. The PIs will interact with the media and include K-12 educators in their fieldwork.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Aster, Richard", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": null, "title": "Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf", "uid": "p0000761", "west": null}, {"awards": "1341585 Sorlien, Christopher", "bounds_geometry": "POLYGON((-180 -73.33,-179.1 -73.33,-178.2 -73.33,-177.3 -73.33,-176.4 -73.33,-175.5 -73.33,-174.6 -73.33,-173.7 -73.33,-172.8 -73.33,-171.9 -73.33,-171 -73.33,-171 -73.864,-171 -74.398,-171 -74.932,-171 -75.466,-171 -76,-171 -76.534,-171 -77.068,-171 -77.602,-171 -78.136,-171 -78.67,-171.9 -78.67,-172.8 -78.67,-173.7 -78.67,-174.6 -78.67,-175.5 -78.67,-176.4 -78.67,-177.3 -78.67,-178.2 -78.67,-179.1 -78.67,180 -78.67,178.5 -78.67,177 -78.67,175.5 -78.67,174 -78.67,172.5 -78.67,171 -78.67,169.5 -78.67,168 -78.67,166.5 -78.67,165 -78.67,165 -78.136,165 -77.602,165 -77.068,165 -76.534,165 -76,165 -75.466,165 -74.932,165 -74.398,165 -73.864,165 -73.33,166.5 -73.33,168 -73.33,169.5 -73.33,171 -73.33,172.5 -73.33,174 -73.33,175.5 -73.33,177 -73.33,178.5 -73.33,-180 -73.33))", "dataset_titles": "Ross Sea unconformities digital grids in depth and two-way time", "datasets": [{"dataset_uid": "601098", "doi": "10.15784/601098", "keywords": "Antarctica; Continental Margin; Geology/Geophysics - Other; Marine Geoscience; Miocene; Oligocene; Seismic Reflection", "people": "Wilson, Douglas S.; Sorlien, Christopher", "repository": "USAP-DC", "science_program": null, "title": "Ross Sea unconformities digital grids in depth and two-way time", "url": "https://www.usap-dc.org/view/dataset/601098"}], "date_created": "Fri, 25 May 2018 00:00:00 GMT", "description": "Intellectual Merit: This project will produce a new compilation of Ross Sea seismic stratigraphy, including new interpretations, that can be used to provide boundary conditions on the tectonic and glacial evolution of West Antarctica and the Ross Sea. The principal goals include compilation of, and interpretation of, all available existing seismic reflection data for the Western Ross Sea, coupled with geophysical modeling to produce paleo-bathymetric reconstructions for the entire 800 km-wide Ross Sea. Specific tasks will include: extending existing work on mapping travel time to reflectors, identifying relations in the seismic data that indicate subsidence through sea level, constructing velocity models for converting travel time to thickness, and using the velocity models to estimate density and porosity of sediments for backstripping analysis. Modeling/backstripping efforts will be used to constrain past bathymetry. Digital interpretations and stratigraphic grids will be provided as supplements to publications. In that way the results of this study can be used in thermal subsidence modeling and restoration of eroded rock to other parts of Ross Embayment and Marie Byrd Land by others. Digital products may be provided in advance of publication to modelers in a way that will not hurt publication chances. Broader impacts: The results of this work will be important for paleo-geographic reconstructions of Antarctica and will therefore be of use to a broad range of researchers, particularly those working in the Ross Sea region. The digital products can be used to test models for the past fluctuations of West Antarctic ice sheets, and in planning for future sediment drilling projects. Two undergraduates to be chosen from applicants will be involved in summer internships held at the University of Rhode Island. Outreach will also include a new website and one or more Wikipedia entries related to Ross Sea sub-sea floor characteristics. The project includes an international collaboration with Dr. Chiara Sauli and others at Instituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in Italy.", "east": -171.0, "geometry": "POINT(177 -76)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -73.33, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sorlien, Christopher; Luyendyk, Bruce P.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.67, "title": "Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea", "uid": "p0000271", "west": 165.0}, {"awards": "1341729 Kirschvink, Joseph", "bounds_geometry": "POLYGON((-58.9 -63.5,-58.63 -63.5,-58.36 -63.5,-58.09 -63.5,-57.82 -63.5,-57.55 -63.5,-57.28 -63.5,-57.01 -63.5,-56.74 -63.5,-56.47 -63.5,-56.2 -63.5,-56.2 -63.62,-56.2 -63.74,-56.2 -63.86,-56.2 -63.98,-56.2 -64.1,-56.2 -64.22,-56.2 -64.34,-56.2 -64.46,-56.2 -64.58,-56.2 -64.7,-56.47 -64.7,-56.74 -64.7,-57.01 -64.7,-57.28 -64.7,-57.55 -64.7,-57.82 -64.7,-58.09 -64.7,-58.36 -64.7,-58.63 -64.7,-58.9 -64.7,-58.9 -64.58,-58.9 -64.46,-58.9 -64.34,-58.9 -64.22,-58.9 -64.1,-58.9 -63.98,-58.9 -63.86,-58.9 -63.74,-58.9 -63.62,-58.9 -63.5))", "dataset_titles": "2016 Paleomagnetic samples from the James Ross Basin, Antarctica; Expedition data of NBP1601", "datasets": [{"dataset_uid": "002665", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1601", "url": "https://www.rvdata.us/search/cruise/NBP1601"}, {"dataset_uid": "601094", "doi": "10.15784/601094", "keywords": "Antarctica; Geochronology; Geology/Geophysics - Other; Glaciology; James Ross Basin; Marine Geoscience; Marine Sediments", "people": "Skinner, Steven; Kirschvink, Joseph", "repository": "USAP-DC", "science_program": null, "title": "2016 Paleomagnetic samples from the James Ross Basin, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601094"}], "date_created": "Fri, 27 Apr 2018 00:00:00 GMT", "description": "Non-Technical Summary: About 80 million years ago, the tip of the Antarctic Peninsula in the vicinity of what is now James Ross Island experienced an episode of rapid subsidence, creating a broad depositional basin that collected sediments eroding from the high mountains to the West. This depression accumulated a thick sequence of fossil-rich, organic-rich sediments of the sort that are known to preserve hydrocarbons, and for which Argentina, Chile, and the United Kingdom have overlapping territorial claims. The rocks preserve one of the highest resolution records of the biological and climatic events that led to the eventual death of the dinosaurs at the Cretaceous-Tertiary boundary (about 66 million years ago). A previous collaboration between scientists from the Instituto Ant\u00e1rtico Argentino (IAA) and NSF-supported teams from Caltech and the University of Washington were able to show that this mass extinction event started nearly 50,000 years before the sudden impact of an asteroid. The asteroid obviously hit the biosphere hard, but something else knocked it off balance well before the asteroid hit. A critical component of the previous work was the use of reversals in the polarity of the Earth?s magnetic field as a dating tool ? magnetostratigraphy. This allowed the teams to correlate the pattern of magnetic reversals from Antarctica with elsewhere on the planet. This includes data from a major volcanic eruption (a flood basalt province) that covered much of India 65 million years ago. The magnetic patterns indicate that the Antarctic extinction started with the first pulse of this massive eruption, which was also coincident with a rapid spike in polar temperature. The Argentinian and US collaborative teams will extend this magnetic polarity record back another ~ 20 million years in time, and expand it laterally to provide magnetic reversal time lines across the depositional basin. They hope to recover the end of the Cretaceous Long Normal interval, which is one of the most distinctive events in the history of Earth?s magnetic field. The new data should refine depositional models of the basin, allow better estimates of potential hydrocarbon reserves, and allow biotic events in the Southern hemisphere to be compared more precisely with those elsewhere on Earth. Other potential benefits of this work include exposing several US students and postdoctoral fellows to field based research in Antarctica, expanding the international aspects of this collaborative work via joint IAA/US field deployments, and follow-up laboratory investigations and personnel exchange of the Junior scientists. Technical Description of Project The proposed research will extend the stratigraphic record in the late Cretaceous and early Tertiary sediments (~ 83 to 65 Ma before present) of the James Ross Basin, Antarctica, using paleo-magnetic methods. Recent efforts provided new methods to analyze these rocks, yielding their primary magnetization, and producing both magnetic polarity patterns and paleomagnetic pole positions. This provided the first reliable age constraints for the younger sediments on Seymour Island, and quantified the sedimentation rate in this part of the basin. The new data will allow resolution of the stable, remnant magnetization of the sediments from the high deposition rate James Ross basin (Tobin et al., 2012), yielding precise chronology/stratigraphy. This approach will be extended to the re-maining portions of this sedimentary basin, and will allow quantitative estimates for tectonic and sedimentary processes between Cretaceous and Early Tertiary time. The proposed field work will refine the position of several geomagnetic reversals that occurred be-tween the end of the Cretaceous long normal period (Chron 34N, ~ 83 Ma), and the lower portion of Chron 31R (~ 71 Ma). Brandy Bay provides the best locality for calibrating the stratigraphic position of the top of the Cretaceous Long Normal Chron, C34N. Although the top of the Cretaceous long normal Chron is one of the most important correlation horizons in the entire geological timescale, it is not properly correlated to the southern hemisphere biostratigraphy. Locating this event, as well as the other reversals, will be a major addition to understanding of the geological history of the Antarctic Peninsula. These data will also help refine tectonic models for the evolution of the Southern continents, which will be of use across the board for workers in Cretaceous stratigraphy (including those involved in oil exploration). This research is a collaborative effort with Dr. Edward Olivero of the Centro Austral de Investigaciones Cientificas (CADIC/CONICET) and Prof. Augusto Rapalini of the University of Buenos Aires. The collaboration will include collection of samples on their future field excursions to important targets on and around James Ross Island, supported by the Argentinian Antarctic Program (IAA). Argentinian scientists and students will also be involved in the US Antarctic program deployments, proposed here for the R/V Laurence Gould, and will continue the pattern of joint international publication of the results.", "east": -56.2, "geometry": "POINT(-57.55 -64.1)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; R/V NBP; USAP-DC", "locations": null, "north": -63.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kirschvink, Joseph; Christensen, John", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -64.7, "title": "Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica", "uid": "p0000276", "west": -58.9}, {"awards": "1425989 Sarmiento, Jorge", "bounds_geometry": "POLYGON((-180 -52.6153,-168.67689 -52.6153,-157.35378 -52.6153,-146.03067 -52.6153,-134.70756 -52.6153,-123.38445 -52.6153,-112.06134 -52.6153,-100.73823 -52.6153,-89.41512 -52.6153,-78.09201 -52.6153,-66.7689 -52.6153,-66.7689 -55.18958,-66.7689 -57.76386,-66.7689 -60.33814,-66.7689 -62.91242,-66.7689 -65.4867,-66.7689 -68.06098,-66.7689 -70.63526,-66.7689 -73.20954,-66.7689 -75.78382,-66.7689 -78.3581,-78.09201 -78.3581,-89.41512 -78.3581,-100.73823 -78.3581,-112.06134 -78.3581,-123.38445 -78.3581,-134.70756 -78.3581,-146.03067 -78.3581,-157.35378 -78.3581,-168.67689 -78.3581,180 -78.3581,178.62318 -78.3581,177.24636 -78.3581,175.86954 -78.3581,174.49272 -78.3581,173.1159 -78.3581,171.73908 -78.3581,170.36226 -78.3581,168.98544 -78.3581,167.60862 -78.3581,166.2318 -78.3581,166.2318 -75.78382,166.2318 -73.20954,166.2318 -70.63526,166.2318 -68.06098,166.2318 -65.4867,166.2318 -62.91242,166.2318 -60.33814,166.2318 -57.76386,166.2318 -55.18958,166.2318 -52.6153,167.60862 -52.6153,168.98544 -52.6153,170.36226 -52.6153,171.73908 -52.6153,173.1159 -52.6153,174.49272 -52.6153,175.86954 -52.6153,177.24636 -52.6153,178.62318 -52.6153,-180 -52.6153))", "dataset_titles": "Biogeochemical profiling float data from the Southern Ocean Carbon and Climate Observation and Modeling (SOCCOM) program.UCSD Research Data Collections DOI:10.6075/J09021PC; Expedition Data; Model output NOAA GFDL CM2_6 Cant Hant storage", "datasets": [{"dataset_uid": "000208", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Biogeochemical profiling float data from the Southern Ocean Carbon and Climate Observation and Modeling (SOCCOM) program.UCSD Research Data Collections DOI:10.6075/J09021PC", "url": "http://library.ucsd.edu/dc/object/bb66239018"}, {"dataset_uid": "001369", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1701"}, {"dataset_uid": "601144", "doi": "10.15784/601144", "keywords": "Antarctica; Anthropogenic Heat; Atmosphere; Carbon Storage; Climate Change; Eddy; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Heat Budget; Modeling; Model Output; Oceans; Paleoclimate; Snow/ice; Snow/Ice; Southern Ocean", "people": "Chen, Haidi", "repository": "USAP-DC", "science_program": null, "title": "Model output NOAA GFDL CM2_6 Cant Hant storage", "url": "https://www.usap-dc.org/view/dataset/601144"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) project seeks to drive a transformative shift in our understanding of the crucial role of the Southern Ocean in taking up anthropogenic carbon and heat, and resupplying nutrients from the abyss to the surface. An observational program will generate vast amounts of new biogeochemical data that will provide a greatly improved view of the dynamics and ecosystem responses of the Southern Ocean. A modeling component will apply these observations to enhancing understanding of the current ocean, reducing uncertainty in projections of future carbon and nutrient cycles and climate. Because it serves as the primary gateway through which the intermediate, deep, and bottom waters of the ocean interact with the surface layers and thus the atmosphere, the Southern Ocean has a profound influence on the oceanic uptake of anthropogenic carbon and heat as well as nutrient resupply from the abyss to the surface. Yet it is the least observed and understood region of the world ocean. The oceanographic community is on the cusp of two major advances that have the potential to transform understanding of the Southern Ocean. The first is the development of new biogeochemical sensors mounted on autonomous profiling floats that allow sampling of ocean biogeochemistry and acidification in 3-dimensional space with a temporal resolution of five to ten days. The SOCCOM float program proposed will increase the average number of biogeochemical profiles measured per month in the Southern Ocean by ~10-30x. The second is that the climate modeling community now has the computational resources and physical understanding to develop fully coupled climate models that can represent crucial mesoscale processes in the Southern Ocean, as well as corresponding models that assimilate observations to produce a state estimate. Together with the observations, this new generation of models provides the tools to vastly improve understanding of Southern Ocean processes and the ability to quantitatively assess uptake of anthropogenic carbon and heat, as well as nutrient resupply, both today and into the future. In order to take advantage of the above technological and modeling breakthroughs, SOCCOM will implement the following research programs: * Theme 1: Observations. Scripps Institution of Oceanography will lead a field program to expand the number of Southern Ocean autonomous profiling floats and equip them with sensors to measure pH, nitrate, and oxygen. The University of Washington and Monterey Bay Aquarium Research Institute will design, build, and oversee deployment of the floats. Scripps will also develop a mesoscale eddying Southern Ocean state estimate that assimilates physical and biogeochemical data into the MIT ocean general circulation model. * Theme 2: Modeling. University of Arizona and Princeton University, together with NOAA\u0027s Geophysical Fluid Dynamics Laboratory (GFDL), will use SOCCOM observations to develop data/model assessment metrics and next-generation model analysis and evaluation, with the goal of improving process level understanding and reducing the uncertainty in projections of our future climate. Led by Climate Central, an independent, non-profit journalism and research organization that promotes understanding of climate science, SOCCOM will collaborate with educators and media professionals to inform policymakers and the public about the challenges of climate change and its impacts on marine life in the context of the Southern Ocean. In addition, the integrated team of SOCCOM scientists and educators will: * communicate data and results of the SOCCOM efforts quickly to the public through established data networks, publications, broadcast media, and a public portal; * train a new generation of diverse ocean scientists, including undergraduate students, graduate students, and postdoctoral fellows versed in field techniques, data calibration, modeling, and communication of research to non-scientists; * transfer new sensor technology and related software to autonomous instrument providers and manufacturers to ensure that they become widely useable.", "east": -66.7689, "geometry": "POINT(-130.26855 -65.4867)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "USAP-DC; R/V NBP; NBP1701; CLIMATE MODELS", "locations": null, "north": -52.6153, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Instrumentation and Support; Antarctic Integrated System Science", "paleo_time": null, "persons": "Sarmiento, Jorge; Rynearson, Tatiana", "platforms": "OTHER \u003e MODELS \u003e CLIMATE MODELS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "PI website", "repositories": "PI website; R2R; USAP-DC", "science_programs": null, "south": -78.3581, "title": "Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM)", "uid": "p0000197", "west": 166.2318}, {"awards": "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; Sletten, Ronald S.; Malin, Michael", "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": "Paragraph for Public Audiences: 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 1980\u0027s and early 1990\u0027s 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. Technical Description of Project: 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.", "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": "1341360 Steig, Eric", "bounds_geometry": "POINT(106 -77.5)", "dataset_titles": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "datasets": [{"dataset_uid": "601031", "doi": "10.15784/601031", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Snow Pit; WAIS Divide Ice Core", "people": "Schoenemann, Spruce; Steig, Eric J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "url": "https://www.usap-dc.org/view/dataset/601031"}], "date_created": "Tue, 06 Jun 2017 00:00:00 GMT", "description": "Steig/1341360 This award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.", "east": 106.0, "geometry": "POINT(106 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -77.5, "title": "Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores", "uid": "p0000316", "west": 106.0}, {"awards": "1043092 Steig, Eric; 1043167 White, James", "bounds_geometry": "POINT(-112.08 -79.47)", "dataset_titles": "Resampling of Deep Polar Ice Cores using Information Theory; Seasonal temperatures in West Antarctica during the Holocene ; Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core; WAIS Divide Ice Core Discrete CH4 (80-3403m)", "datasets": [{"dataset_uid": "601603", "doi": "10.15784/601603", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Seasonality; Seasonal Temperatures; Temperature; Water Isotopes; West Antarctic Ice Sheet", "people": "Jones, Tyler R.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal temperatures in West Antarctica during the Holocene ", "url": "https://www.usap-dc.org/view/dataset/601603"}, {"dataset_uid": "601274", "doi": "10.15784/601274", "keywords": "Antarctica; Delta 18O; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Snow/ice; Snow/Ice; WAIS Divide; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Bradley, Elizabeth; White, James; Vaughn, Bruce; Morris, Valerie; Garland, Joshua; Price, Michael; Jones, Tyler R.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "url": "https://www.usap-dc.org/view/dataset/601274"}, {"dataset_uid": "601365", "doi": "10.15784/601365", "keywords": "Antarctica; Delta 18O; Isotope; WAIS Divide; WAIS Divide Ice Core; West Antarctic Ice Sheet", "people": "Garland, Joshua; Jones, Tyler R.; Vaughn, Bruce; Morris, Valerie; White, James", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Resampling of Deep Polar Ice Cores using Information Theory", "url": "https://www.usap-dc.org/view/dataset/601365"}, {"dataset_uid": "600169", "doi": "10.15784/600169", "keywords": "Antarctica; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Snow Accumulation; WAIS Divide; WAIS Divide Ice Core", "people": "White, James; Vaughn, Bruce; Jones, Tyler R.; Morris, Valerie", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "url": "https://www.usap-dc.org/view/dataset/600169"}, {"dataset_uid": "601741", "doi": "10.15784/601741", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Methane; WAIS", "people": "Sowers, Todd A.; Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice Core Discrete CH4 (80-3403m)", "url": "https://www.usap-dc.org/view/dataset/601741"}], "date_created": "Thu, 15 Sep 2016 00:00:00 GMT", "description": "Steig/1043092 This award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.", "east": -112.08, "geometry": "POINT(-112.08 -79.47)", "instruments": null, "is_usap_dc": true, "keywords": "LABORATORY", "locations": null, "north": -79.47, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "White, James; Vaughn, Bruce; Jones, Tyler R.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.47, "title": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "uid": "p0000078", "west": -112.08}, {"awards": "1141275 Warren, Stephen", "bounds_geometry": null, "dataset_titles": "Antarctic field campaign data page", "datasets": [{"dataset_uid": "001399", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Antarctic field campaign data page", "url": "http://www.atmos.washington.edu/articles/EastAntarctica_SeaIceAlbedos_SnowImpurities/"}], "date_created": "Fri, 30 Jan 2015 00:00:00 GMT", "description": "The albedo, or reflection coefficient, is a measure of the diffuse reflectivity of an irradiated surface. With the sunlit atmosphere as a light source, and sea-ice as a diffuse reflecting surface, the albedo would be the fraction of incident light that is returned to the atmosphere. A perfect (white) reflecting surface would have an albedo of 1; a perfect (black) absorbing surface would have an albedo of 0. The albedo of sea-ice is needed to assess the solar energy budget of the marginal ice zone, to compute the partial solar bands in radiation budgets in general circulation and earth system models, and is also needed to interpret remote sensing imagery data products. Applications requiring albedos further into the near IR, out to 2500nm, are assumed or approximated. Modern spectral radiometers, such as will be used in this campaign on a Southern Ocean voyage from Hobart to Antarctica, can extend these measurements of albedo from 350 to 2500nm, allowing earlier estimates to be verified, or corrected. Surfaces to be encountered on this research cruise are expected to include open water, grease ice, nila ice, pancake ice, young grey ice, young grey-white ice, along with first year ice. The presence of variable amounts of snow on these surfaces is also of interest. Light absorbing impurities in the snow and ice, including black carbon and organic matter (brown carbon) are different from those found in Arctic Sea ice, the Antarctic being so remote from combustion sources. This may allow better understanding of the seasonal cycles, energy budgets and their recent trends in spatial extent and thickness. The project will also broaden the educational experiences of both US and Australian students participating in the measurement campaign", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Radiometers; Radiation Budgets; Sea Ice; Energy Budgets; Impurities; COMPUTERS; Albedo; Spectral; LABORATORY; Antarctica; Snow Temperature; Reflecting Surface; Snow Density; R/V AA", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Warren, Stephen; Zatko, Maria", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V AA", "repo": "PI website", "repositories": "PI website", "science_programs": null, "south": null, "title": "Spectral and Broadband Albedo of Antarctic Sea-ice Types", "uid": "p0000375", "west": null}, {"awards": "1043167 White, James; 1043092 Steig, Eric", "bounds_geometry": null, "dataset_titles": "17O excess from WAIS Divide, 0 to 25 ka BP; WAIS Divide Ice Core Discrete CH4 (80-3403m); WAIS Divide WDC06A Oxygen Isotope Record", "datasets": [{"dataset_uid": "601741", "doi": "10.15784/601741", "keywords": "Antarctica; Ch4; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Methane; WAIS", "people": "Sowers, Todd A.; Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice Core Discrete CH4 (80-3403m)", "url": "https://www.usap-dc.org/view/dataset/601741"}, {"dataset_uid": "601413", "doi": "10.15784/601413", "keywords": "Antarctica; Ice Core; Oxygen Isotope; WAIS Divide", "people": "Steig, Eric J.; Schoenemann, Spruce", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "17O excess from WAIS Divide, 0 to 25 ka BP", "url": "https://www.usap-dc.org/view/dataset/601413"}, {"dataset_uid": "609629", "doi": "10.7265/N5GT5K41", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "people": "Steig, Eric J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide WDC06A Oxygen Isotope Record", "url": "https://www.usap-dc.org/view/dataset/609629"}], "date_created": "Sat, 06 Dec 2014 00:00:00 GMT", "description": "This award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e INFRARED LASER SPECTROSCOPY; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e INFRARED LASER SPECTROSCOPY", "is_usap_dc": true, "keywords": "AMD; ANALYTICAL LAB; USAP-DC; Amd/Us; LABORATORY; ICE CORE RECORDS; Antarctica; Wais Divide-project; FIELD SURVEYS; USA/NSF", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e ANALYTICAL LAB; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "uid": "p0000010", "west": null}, {"awards": "0739779 Warren, Stephen; 1142963 Warren, Stephen", "bounds_geometry": "POLYGON((157 -76,158.1 -76,159.2 -76,160.3 -76,161.4 -76,162.5 -76,163.6 -76,164.7 -76,165.8 -76,166.9 -76,168 -76,168 -76.2,168 -76.4,168 -76.6,168 -76.8,168 -77,168 -77.2,168 -77.4,168 -77.6,168 -77.8,168 -78,166.9 -78,165.8 -78,164.7 -78,163.6 -78,162.5 -78,161.4 -78,160.3 -78,159.2 -78,158.1 -78,157 -78,157 -77.8,157 -77.6,157 -77.4,157 -77.2,157 -77,157 -76.8,157 -76.6,157 -76.4,157 -76.2,157 -76))", "dataset_titles": "Ice on the Oceans of Snowball Earth Project Data", "datasets": [{"dataset_uid": "000183", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Ice on the Oceans of Snowball Earth Project Data", "url": "https://digital.lib.washington.edu/researchworks/handle/1773/37320"}], "date_created": "Wed, 10 Jul 2013 00:00:00 GMT", "description": "The climatic changes of late Precambrian time, 600-800 million years ago, included episodes of extreme glaciation, during which ice may have covered nearly the entire ocean for several million years, according to the Snowball Earth hypothesis. These episodes would hold an important place in Earth?s evolutionary history; they could have encouraged biodiversity by trapping life forms in small isolated ice-free areas, or they could have caused massive extinctions that cleared the path for new life forms to fill empty niches. What caused the Earth to become iced over, and what later caused the ice to melt? Scientific investigation of these questions will result in greater understanding of the climatic changes that the Earth can experience, and will enable better predictions of future climate. This project involves Antarctic field observations as well as laboratory studies and computer modeling. The aim of this project is not to prove or disprove the Snowball Earth hypothesis but rather to quantify processes that are important for simulating snowball events in climate models. The principal goal is to identify the types of ice that would have been present on the frozen ocean, and to determine how much sunlight they would reflect back to space. Reflection of sunlight by bright surfaces of snow and ice is what would maintain the cold climate at low latitudes. The melting of the ocean required buildup of greenhouse gases, but it was probably aided by deposition of desert dust and volcanic ash darkening the snow and ice. With so much ice on the Earth?s surface, even small differences in the amount of light that the ice absorbed or reflected could cause significant changes in climate. The properties of the ice would also determine where, and in what circumstances, photosynthetic life could have survived. Some kinds of ice that are rare on the modern Earth may have been pivotal in allowing the tropical ocean to freeze. The ocean surfaces would have included some ice types that now exist only in Antarctica: bare cold sea ice with precipitated salts, and \"blue ice\" areas of the Transantarctic Mountains that were exposed by sublimation and have not experienced melting. Field expeditions were mounted to examine these ice types, and the data analysis is underway. A third ice type, sea ice with a salt crust, is being studied in a freezer laboratory. Modeling will show how sunlight would interact with ice containing light-absorbing dust and volcanic ash. Aside from its reflection of sunlight, ice on the Snowball ocean would have been thick enough to flow under its own weight, invading all parts of the ocean. Yet evidence for the survival of photosynthetic life indicates that some regions of liquid water were maintained at the ocean surface. One possible refuge for photosynthetic organisms is a bay at the far end of a nearly enclosed tropical sea, formed by continental rifting and surrounded by desert, such as the modern Red Sea. A model of glacier flow is being developed to determine the dimensions of the channel, connecting the sea to the ocean, necessary to prevent invasion by the flowing ice yet maintain a water supply to replenish evaporation.", "east": 168.0, "geometry": "POINT(162.5 -77)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Warren, Stephen; Light, Bonnie; Campbell, Adam; Carns, Regina; Dadic, Ruzica; Mullen, Peter; Brandt, Richard; Waddington, Edwin D.", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website", "science_programs": null, "south": -78.0, "title": "Ocean Surfaces on Snowball Earth", "uid": "p0000402", "west": 157.0}, {"awards": "0631973 Joughin, Ian; 0632031 Das, Sarah", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 20 Jun 2012 00:00:00 GMT", "description": "Joughin 0631973\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to gather data to better understand the mass balance of the West Antarctic Ice Sheet, in the Pine Island and Thwaites region, through the combination of radar altimetry and surface-based ice-core measurements of accumulation. The intellectual merit of the project is that the results of the field work will provide information on decadal-scale average accumulation extending back through the last century and will help constrain a modeling effort to determine how coastal changes propagate inland, to allow better prediction of future change. Comparison of the basin averaged accumulation with ice discharge determined using Interferometric Synthetic Aperture Radar (InSAR) velocity data will provide improved mass-balance estimates. Study of changes in flow speed will produce a record of mass balance over the last three decades. Analysis of the satellite altimeter record in conjunction with annual accumulation estimates also will provide estimates of changes and variability in mass balance. The broader impacts of the work are that it will make a significant contribution to future IPCC estimates of sea level, which are important for projection of the impacts of increased sea level on coastal communities. The research will contribute to the graduate education of students at the Universities of Washington and Kansas and will enrich K-12 education through the direct participation of the PIs in classroom activities. Informal science education includes 4-day glacier flow demonstrations at the Polar Science Weekend held annually at the Pacific Science Center in Seattle. The project also will communicate results through Center for the Remote Sensing of Ice Sheets (CReSIS) outreach effort. All field and remotely-sensed data sets will be archived and distributed by the National Snow and Ice Data Center. This project is relevant to IPY in that the West Antarctic Ice Sheet is losing mass, in large part because of rapid thinning of the Amundsen Coast glaciers so, it will directly address the NSF IPY emphasis on \"ice sheet history and dynamics.\" The project is also international in scope.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "Not provided; FIELD INVESTIGATION; Flow Speed; Antarctic; LABORATORY; Ice Sheet Accumulation Rate; Mass Balance; Accumulation; Insar; SATELLITES; FIELD SURVEYS; Ice Core; Radar Altimetry; Ice Velocity", "locations": "Antarctic", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Joughin, Ian; Medley, Brooke; Das, Sarah", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e SATELLITES", "repositories": null, "science_programs": null, "south": null, "title": "IPY: Collaborative Proposal: Constraining the Mass-Balance Deficit of the Amundsen Coast\u0027s Glaciers", "uid": "p0000542", "west": null}, {"awards": "0440819 Taylor, Kendrick", "bounds_geometry": "POINT(112.1 -79.46667)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 19 Jun 2012 00:00:00 GMT", "description": "This award supports a project that is part of the West Antarctic Ice Sheet Divide (WAIS Divide) program; which is a multi-disciplinary multi-institutional program to investigate the causes of natural changes in climate, the influence of the West Antarctic ice sheet on sea level, and the biology of deep ice. The WAIS Divide core will be unique among Antarctic ice cores in that it will have discernable annual layers for the last 40,000 years. A critical element of the program is to determine the age of the ice so that the climate proxies measured on the core can be interpreted in terms of age, not just depth. This project will make electrical measurements that can identify the annual layers. This information will be combined with information from other investigators to develop an annually resolved timescale over the last 40,000 years. This timescale will be the foundation on which the recent climate records are interpreted. Electrical measurements will also be used to produce two-dimensional images of the ice core stratigraphy; allowing sections of the core with abnormal stratigraphy to be identified. The broader impacts of this project include exposing a diverse group of undergraduate and graduate students to ice core research and assisting the Smithsonian National Museum of Natural History in Washington, D.C to develop a paleoclimate/ice core display.", "east": 112.1, "geometry": "POINT(112.1 -79.46667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "Annual Layers; Time Scale; FIELD INVESTIGATION; Stratigraphy; FIELD SURVEYS; Glaciology; Electrical Measurements; Antarctic; Not provided; Ice Sheet; Ice Core; LABORATORY; Climate Proxies", "locations": "Antarctic", "north": -79.46667, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Taylor, Kendrick C.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -79.46667, "title": "Investigation of the Stratigraphy and Time Scale of the WAIS Divide Ice Core Using Electrical Methods", "uid": "p0000373", "west": 112.1}, {"awards": "0636997 Waddington, Edwin", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 20 Mar 2012 00:00:00 GMT", "description": "Waddington/0636997\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to integrate three lines of glaciology research, previously treated independently. First, internal layers in ice sheets, detected by ice-penetrating radar, retain information about past spatial and temporal patterns of ice accumulation. Ice-flow modelers can recover this information, using geophysical inverse methods; however, the ages of the layers must be known, through interpolation where they intersect a well-dated ice core. \u003cbr/\u003eSecond, concentrations of methane and some other atmospheric constituents vary through time as climate changes. However, the atmosphere is always well mixed, and concentrations are similar world-wide at any one time, so gas variations from an undated core can be correlated with those in a well-dated core such as GISP2. Because air in near-surface firn mixes readily with the atmosphere above, the air that is trapped in bubbles deep in the firn is typically hundreds to thousands of years younger than that firn. Gas geochemists must calculate this age difference, called delta-age, with a firn-densification model before the ice enclosing the gas can be dated accurately. To calculate delta-age, they must know the temperature and the snow accumulation rate at the time and place where the snow fell. Third, gases can be correlated between cores only at times when the atmosphere changed, so ice-core dates must be interpolated at depths between the sparse dated points. Simplistic interpolation schemes can create undesirable artifacts in the depth-age profile. The intellectual merit of this project is that it will develop new interpolation methods that calculate layer thinning over time due to ice-flow mechanics. Accurate interpolation also requires a spatial and temporal accumulation history. These three issues are coupled through accumulation patterns and ice-core dates. This project will develop an integrated inversion procedure to solve all three problems simultaneously. The new method will incorporate ice-penetrating radar profile data and ice-core data, and will find self-consistent: spatial/temporal accumulation patterns; delta-age profiles for ice cores; and reliably interpolated depth-age profiles. The project will then: recalculate the depth-age profile at Byrd Station, Antarctica; provide a preliminary depth-age at the West Antarctic Ice Sheet (WAIS) in the initial stages of drilling, using radar layers with estimated ages traced from Byrd Station; and generate a self-consistent depth-age relationship for Taylor Dome, Antarctica over the past 20ka, where low accumulation has created uncertainty in dating, accumulation, and controversy over delta-age estimates. The broader impacts of the project are that it will support the PhD research of a female graduate student, and her continued outreach work with Making Connections, a non-profit program through the University of Washington Women\u0027s Center, which matches professional women mentors with minority high-school women interested in mathematics and science, disciplines where they are traditionally under-represented. The graduate student will also work with Girls on Ice, a ten-day glacier field program, taught by women scientist instructors, emphasizing scientific observation through immersion, leadership skills and safety awareness.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Internal Layers; LABORATORY; Ice Core; FIELD SURVEYS; Firn; FIELD INVESTIGATION; Accumulation; Glaciology; Climate Change; Ice Sheet", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Carns, Regina; Hay, Mike; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Self-consistent Ice Dynamics, Accumulation, Delta-age, and Interpolation of Sparse Age Data using an Inverse Approach", "uid": "p0000376", "west": null}, {"awards": "0636818 Stone, John", "bounds_geometry": "POLYGON((-157 -85,-156 -85,-155 -85,-154 -85,-153 -85,-152 -85,-151 -85,-150 -85,-149 -85,-148 -85,-147 -85,-147 -85.3,-147 -85.6,-147 -85.9,-147 -86.2,-147 -86.5,-147 -86.8,-147 -87.1,-147 -87.4,-147 -87.7,-147 -88,-148 -88,-149 -88,-150 -88,-151 -88,-152 -88,-153 -88,-154 -88,-155 -88,-156 -88,-157 -88,-157 -87.7,-157 -87.4,-157 -87.1,-157 -86.8,-157 -86.5,-157 -86.2,-157 -85.9,-157 -85.6,-157 -85.3,-157 -85))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 05 Aug 2011 00:00:00 GMT", "description": "Hall/0636687\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, surface velocity and surface mass balance will be measured to constrain an ice-flow model of the glacier. This model will be used to help interpret the dated geologic sequences. The intellectual merit of the project relates to gaining a better understanding of the West Antarctic Ice Sheet and how changing activity of fast-flowing outlet glaciers and ice streams exerts strong control on the mass balance of the ice sheet. Previous work suggests that grounding-line retreat in the Ross Sea continued into the late Holocene and left open the possibility of ongoing deglaciation as part of a long-term trend. Results from Reedy Glacier, an outlet glacier just behind the grounding line, suggest that retreat may have slowed substantially over the past 2000 years and perhaps even stopped. By coupling the work on Scott Glacier with recent data from Reedy Glacier, the grounding-line position will be bracketed and it should be possible to establish whether the retreat has truly ended or if it is ongoing. The broader impacts of the work relate to the societal relevance of an improved understanding of the West Antarctic ice sheet to establish how it will respond to current and possible future environmental changes. The work addresses this key goal of the West Antarctic Ice Sheet Initiative, as well as the International Polar Year focus on ice sheet history and dynamics. The work will develop future scientists through the education and training of one undergraduate and two Ph.D. students, interaction with K-12 students through classroom visits, web-based \u0027expedition\u0027 journals, letters from the field, and discussions with teachers. Results from this project will be posted with previous exposure dating results from Antarctica, on the University of Washington Cosmogenic Nuclide Lab website, which also provides information about chemical procedures and calculation methods to other scientists working with cosmogenic nuclides.", "east": -147.0, "geometry": "POINT(-152 -86.5)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -85.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Stone, John; Conway, Howard", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -88.0, "title": "Collaborative Research:Grounding-line Retreat in the Southern Ross Sea - Constraints from Scott Glacier", "uid": "p0000149", "west": -157.0}, {"awards": "0424589 Gogineni, S. Prasad", "bounds_geometry": "POLYGON((-137 -74,-132.1 -74,-127.2 -74,-122.3 -74,-117.4 -74,-112.5 -74,-107.6 -74,-102.7 -74,-97.8 -74,-92.9 -74,-88 -74,-88 -74.65,-88 -75.3,-88 -75.95,-88 -76.6,-88 -77.25,-88 -77.9,-88 -78.55,-88 -79.2,-88 -79.85,-88 -80.5,-92.9 -80.5,-97.8 -80.5,-102.7 -80.5,-107.6 -80.5,-112.5 -80.5,-117.4 -80.5,-122.3 -80.5,-127.2 -80.5,-132.1 -80.5,-137 -80.5,-137 -79.85,-137 -79.2,-137 -78.55,-137 -77.9,-137 -77.25,-137 -76.6,-137 -75.95,-137 -75.3,-137 -74.65,-137 -74))", "dataset_titles": "Airborne radar profiles of the Whillans, Bindschadler, and Kamb Ice Streams; Archive of data; Ice-penetrating radar internal stratigraphy over Dome C and the wider East Antarctic Plateau; Ku-band Radar Echograms; Radar Depth Sounder Echograms and Ice Thickness; Snow Radar Echograms", "datasets": [{"dataset_uid": "601048", "doi": "10.15784/601048", "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ku-Band; Navigation; Radar", "people": "Rodriguez, Fernando; Gogineni, Prasad; Li, Jilu; Paden, John; Allen, Chris; Leuschen, Carl", "repository": "USAP-DC", "science_program": null, "title": "Ku-band Radar Echograms", "url": "https://www.usap-dc.org/view/dataset/601048"}, {"dataset_uid": "601047", "doi": "10.15784/601047", "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; MCoRDS; Navigation; Radar", "people": "Paden, John; Rodriguez, Fernando; Gogineni, Prasad; Allen, Chris; Li, Jilu; Leuschen, Carl", "repository": "USAP-DC", "science_program": null, "title": "Radar Depth Sounder Echograms and Ice Thickness", "url": "https://www.usap-dc.org/view/dataset/601047"}, {"dataset_uid": "600384", "doi": "10.15784/600384", "keywords": "Airborne Radar; Antarctica; Basler; Glaciers/ice Sheet; Glaciers/Ice Sheet; Kamb Ice Stream; Radar; Siple Coast; Whillans Ice Stream", "people": "Paden, John; Hale, Richard", "repository": "USAP-DC", "science_program": null, "title": "Airborne radar profiles of the Whillans, Bindschadler, and Kamb Ice Streams", "url": "https://www.usap-dc.org/view/dataset/600384"}, {"dataset_uid": "601049", "doi": "10.15784/601049", "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Navigation; Radar; Snow", "people": "Rodriguez, Fernando; Allen, Chris; Li, Jilu; Gogineni, Prasad; Paden, John; Leuschen, Carl", "repository": "USAP-DC", "science_program": null, "title": "Snow Radar Echograms", "url": "https://www.usap-dc.org/view/dataset/601049"}, {"dataset_uid": "601411", "doi": "10.15784/601411", "keywords": "Antarctica; East Antarctic Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; ICECAP; Ice Penetrating Radar; Internal Reflecting Horizons", "people": "Muldoon, Gail R.; Young, Duncan A.; Cavitte, Marie G. P; Ritz, Catherine; Greenbaum, Jamin; Ng, Gregory; Kempf, Scott D.; Quartini, Enrica; Paden, John; Frezzotti, Massimo; Roberts, Jason; Tozer, Carly; Schroeder, Dustin; Mulvaney, Robert; Blankenship, Donald D.", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "Ice-penetrating radar internal stratigraphy over Dome C and the wider East Antarctic Plateau", "url": "https://www.usap-dc.org/view/dataset/601411"}, {"dataset_uid": "002497", "doi": "", "keywords": null, "people": null, "repository": "Project website", "science_program": null, "title": "Archive of data", "url": "https://www.cresis.ku.edu/data/accumulation"}], "date_created": "Wed, 01 Jun 2011 00:00:00 GMT", "description": "This award is for the continuation of the Center for Remote Sensing of Ice Sheets (CReSIS), an NSF Science and Technology Center (STC) established in June 2005 to study present and probable future contributions of the Greenland and Antarctic ice sheets to sea-level rise. The Center?s vision is to understand and predict the role of polar ice sheets in sea level change. In particular, the Center?s mission is to develop technologies, to conduct field investigations, to compile data to understand why many outlet glaciers and ice streams are changing rapidly, and to develop models that explain and predict ice sheet response to climate change. The Center?s mission is also to educate and train a diverse population of graduate and undergraduate students in Center-related disciplines and to encourage K-12 students to pursue careers in science, technology, engineering and mathematics (STEM-fields). The long-term goals are to perform a four-dimensional characterization (space and time) of rapidly changing ice-sheet regions, develop diagnostic and predictive ice-sheet models, and contribute to future assessments of sea level change in a warming climate. In the first five years, significant progress was made in developing, testing and optimizing innovative sensors and platforms and completing a major aircraft campaign, which included sounding the channel under Jakobshavn Isbr\u00e6. In the second five years, research will focus on the interpretation of integrated data from a suite of sensors to understand the physical processes causing changes and the subsequent development and validation of models. Information about CReSIS can be found at http://www.cresis.ku.edu.\u003cbr/\u003e\u003cbr/\u003eThe intellectual merits of the STC are the multidisciplinary research it enables its faculty, staff and students to pursue, as well as the broad education and training opportunities it provides to students at all levels. During the first phase, the Center provided scientists and engineers with a collaborative research environment and the opportunity to interact, enabling the development of high-sensitivity radars integrated with several airborne platforms and innovative seismic instruments. Also, the Center successfully collected data on ice thickness and bed conditions, key variables in the study of ice dynamics and the development of models, for three major fast-flowing glaciers in Greenland. During the second phase, the Center will collect additional data over targeted sites in areas undergoing rapid changes; process, analyze and interpret collected data; and develop advanced process-oriented and ice sheet models to predict future behavior. The Center will continue to provide a rich environment for multidisciplinary education and mentoring for undergraduate students, graduate students, and postdoctoral fellows, as well as for conducting K-12 education and public outreach. The broader impacts of the Center stem from addressing a global environmental problem with critical societal implications, providing a forum for citizens and policymakers to become informed about climate change issues, training the next generation of scientists and engineers to serve the nation, encouraging underrepresented students to pursue careers in STEM-related fields, and transferring new technologies to industry. Students involved in the Center find an intellectually stimulating atmosphere where collaboration between disciplines is the norm and exposure to a wide variety of methodologies and scientific issues enriches their educational experience. The next generation of researchers should reflect the diversity of our society; the Center will therefore continue its work with ECSU to conduct outreach and educational programs that attract minority students to careers in science and technology. The Center has also established a new partnership with ADMI that supports faculty and student exchanges at the national level and provides expanded opportunities for students and faculty to be involved in Center-related research and education activities. These, and other collaborations, will provide broader opportunities to encourage underrepresented students to pursue STEM careers. \u003cbr/\u003e\u003cbr/\u003eAs lead institution, The University of Kansas (KU) provides overall direction and management, as well as expertise in radar and remote sensing, Uninhabited Aerial Vehicles (UAVs), and modeling and interpretation of data. Five partner institutions and a DOE laboratory play critical roles in the STC. The Pennsylvania State University (PSU) continues to participate in technology development for seismic measurements, field activities, and modeling. The Center of Excellence in Remote Sensing, Education and Research (CERSER) at Elizabeth City State University (ECSU) contributes its expertise to analyzing satellite data and generating high-level data products. ECSU also brings to the Center their extensive experience in mentoring and educating traditionally under-represented students. ADMI, the Association of Computer and Information Science/Engineering Departments at Minority Institutions, expands the program?s reach to underrepresented groups at the national level. Indiana University (IU) provides world-class expertise in CI and high-performance computing to address challenges in data management, processing, distribution and archival, as well as high-performance modeling requirements. The University of Washington (UW) provides expertise in satellite observations of ice sheets and process-oriented interpretation and model development. Los Alamos National Laboratory (LANL) contributes in the area of ice sheet modeling. All partner institutions are actively involved in the analysis and interpretation of observational and numerical data sets.", "east": -88.0, "geometry": "POINT(-112.5 -77.25)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS", "is_usap_dc": true, "keywords": "Remote Sensing; Not provided; Pine Island; Ice Sheet; DHC-6; Antarctic; Thwaites Region; Antarctica; Mass Balance; Accumulation; Velocity; Insar", "locations": "Antarctica; Antarctic; Pine Island; Thwaites Region", "north": -74.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Braaten, David; Joughin, Ian; Steig, Eric J.; Das, Sarah; Paden, John; Gogineni, Prasad", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e DHC-6; Not provided", "repo": "USAP-DC", "repositories": "Project website; USAP-DC", "science_programs": null, "south": -80.5, "title": "Center for Remote Sensing of Ice Sheets (CReSIS)", "uid": "p0000102", "west": -137.0}, {"awards": "0338151 Raymond, Charles", "bounds_geometry": "POINT(-112.086 -79.468)", "dataset_titles": "Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica; Surface Elevation and Ice Thickness, Western Marie Byrd Land, Antarctica", "datasets": [{"dataset_uid": "609470", "doi": "10.7265/N5416V0W", "keywords": "Airborne Radar; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Radar; WAIS Divide", "people": "Raymond, Charles; Matsuoka, Kenichi", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica", "url": "https://www.usap-dc.org/view/dataset/609470"}, {"dataset_uid": "609119", "doi": "10.7265/N5BZ63ZH", "keywords": "Airborne Radar; Airplane; Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marie Byrd Land", "people": "Wilson, Douglas S.; Luyendyk, Bruce P.", "repository": "USAP-DC", "science_program": null, "title": "Surface Elevation and Ice Thickness, Western Marie Byrd Land, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609119"}], "date_created": "Tue, 11 May 2010 00:00:00 GMT", "description": "This award supports an investigation of spatial variations of ice temperature and subglacial conditions using available ice-penetrating radar data around a future deep ice coring site near the Ross and Amundsen flow divide of West Antarctic Ice Sheet. Besides geometry of reflection layers the focus will be on intensities of radar echoes from within ice deeper than several hundred meters and will also examine echoes from the bed. Preliminary studies on theory and comparison with Japanese radar data from East Antarctica suggest that large spatial variations of the vertical gradient of radar echoes from within ice exist and are caused primarily by ice temperature and secondarily by crystal-orientation fabric. The hypothesis that the vertical gradient is a proxy of ice temperature will be tested. The project will utilize an existing data set from the Support Office for Aerogeophysical Research in Antarctica (SOAR) and will complement work already underway at University of Texas to analyze the radar data. The project will provide undergraduate research experience with an emphasis on computer analysis of time series and large data sets as well as development of web-based resource of results and methods and will support an international collaboration between US and Japan through discussions on the preliminary results from their study sites. Practical procedures developed through this study will be downloadable from the project\u0027s web site in the third year and will allow investigation of other ice sheets using existing radar data sets. This project will contribute to the interpretation of the future inland West Antarctic ice core and will help in the understanding of ice sheet history and climate change.", "east": -112.086, "geometry": "POINT(-112.086 -79.468)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e ALTIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e RADAR ALTIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "SOAR; Ice Sheet Elevation; Antarctic Ice Sheet; Layers; USAP-DC; West Antarctic; FIELD INVESTIGATION; Amundsen; Ice Sheet; Airborne Laser Altimetry; Ice Surface; Not provided; Ice Penetrating Radar; Ice Sheet Thickness; Ice Extent; Ice Surface Elevation; Ice Cover; Ice Deformation; FIELD SURVEYS; Antarctica; Ground Ice; Subglacial; Reflection Layers; West Antarctic Ice Sheet; Ice Surface Temperature; LABORATORY; Amundsen Flow Divide; Radar Echo Sounding; Internal Layering; Radar Altimetry; Ice; Radar Echoes; Englacial; Crystal Orientation Fabric; Ice Thickness; Altimetry; Ice Temperature; Radar Echo Sounder; Ice Thickness Distribution", "locations": "Antarctic Ice Sheet; Antarctica; West Antarctic; Amundsen; Amundsen Flow Divide; West Antarctic Ice Sheet", "north": -79.468, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Raymond, Charles; Matsuoka, Kenichi; Luyendyk, Bruce P.; Wilson, Douglas S.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.468, "title": "Glaciological Characteristics of the Ross/Amundsen Sea Ice-flow Divide Deduced by a New Analysis of Ice-penetrating Radar Data", "uid": "p0000017", "west": -112.086}, {"awards": "0337159 McPhee, Miles", "bounds_geometry": "POLYGON((-64.71659 -53.00174,-57.631677 -53.00174,-50.546764 -53.00174,-43.461851 -53.00174,-36.376938 -53.00174,-29.292025 -53.00174,-22.207112 -53.00174,-15.122199 -53.00174,-8.037286 -53.00174,-0.952373 -53.00174,6.13254 -53.00174,6.13254 -54.292069,6.13254 -55.582398,6.13254 -56.872727,6.13254 -58.163056,6.13254 -59.453385,6.13254 -60.743714,6.13254 -62.034043,6.13254 -63.324372,6.13254 -64.614701,6.13254 -65.90503,-0.952373 -65.90503,-8.037286 -65.90503,-15.122199 -65.90503,-22.207112 -65.90503,-29.292025 -65.90503,-36.376938 -65.90503,-43.461851 -65.90503,-50.546764 -65.90503,-57.631677 -65.90503,-64.71659 -65.90503,-64.71659 -64.614701,-64.71659 -63.324372,-64.71659 -62.034043,-64.71659 -60.743714,-64.71659 -59.453385,-64.71659 -58.163056,-64.71659 -56.872727,-64.71659 -55.582398,-64.71659 -54.292069,-64.71659 -53.00174))", "dataset_titles": "Expedition Data; Processed ADCP Sonar and CTD Data from the Maud Rise acquired during the Nathaniel B. Palmer expedition NBP0506", "datasets": [{"dataset_uid": "601342", "doi": null, "keywords": "ADCP Acoustic Doppler Current Profiler; Antarctica; CTD; Maud Rise; NBP0506; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Southern Ocean; Temperature; Turbulance; Weddell Sea", "people": "McPhee, Miles G.", "repository": "USAP-DC", "science_program": null, "title": "Processed ADCP Sonar and CTD Data from the Maud Rise acquired during the Nathaniel B. Palmer expedition NBP0506", "url": "https://www.usap-dc.org/view/dataset/601342"}, {"dataset_uid": "001590", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0506"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is an investigation into one mechanism by which deep ocean convection can evolve from stable initial conditions, to the extent that it becomes well enough established to bring warm water to the surface and melt an existing ice cover in late, or possibly even mid-winter. The specific study will investigate how the non-linear dependence of seawater density on temperature and salinity (the equation of state) can enhance vertical convection under typical antarctic conditions. When layers of seawater with similar densities but strong contrasts in temperature and salinity interact, there are a number of possible non-linear instabilities that can convert existing potential energy to turbulent energy. In the Weddell Sea, a cold surface mixed layer is often separated from the underlying warm, more saline water by a thin, weak pycnocline, making the water column particularly susceptible to an instability associated with thermobaricity (the pressure dependence of the thermal expansion coefficient). The project is a collaboration between New York University, Earth and Space Research, the University of Washington, the Naval Postgraduate School, and McPhee Research Company.\u003cbr/\u003eThe work has strong practical applications in contributing to the explanation for the existence of the Weddell Polynya, a 300,000 square kilometer area of open water within the seasonal sea ice of the Weddell Sea, from approximately 1975 to 1979. It has not recurred since, although indications of much smaller and less persistent areas of open water do occur in the vicinity of the Maud Rise seamount. \u003cbr/\u003e The experimental component will be carried out on board the RVIB Nathaniel B. Palmer between July and September, 2005.", "east": 6.13254, "geometry": "POINT(-29.292025 -59.453385)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -53.00174, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "McPhee, Miles G.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -65.90503, "title": "Collaborative Research: The Maud Rise Nonlinear Equation of State Study (MaudNESS)", "uid": "p0000579", "west": -64.71659}, {"awards": "9814622 Wiens, Douglas", "bounds_geometry": "POLYGON((-70.90604 -52.35474,-69.307306 -52.35474,-67.708572 -52.35474,-66.109838 -52.35474,-64.511104 -52.35474,-62.91237 -52.35474,-61.313636 -52.35474,-59.714902 -52.35474,-58.116168 -52.35474,-56.517434 -52.35474,-54.9187 -52.35474,-54.9187 -53.658393,-54.9187 -54.962046,-54.9187 -56.265699,-54.9187 -57.569352,-54.9187 -58.873005,-54.9187 -60.176658,-54.9187 -61.480311,-54.9187 -62.783964,-54.9187 -64.087617,-54.9187 -65.39127,-56.517434 -65.39127,-58.116168 -65.39127,-59.714902 -65.39127,-61.313636 -65.39127,-62.91237 -65.39127,-64.511104 -65.39127,-66.109838 -65.39127,-67.708572 -65.39127,-69.307306 -65.39127,-70.90604 -65.39127,-70.90604 -64.087617,-70.90604 -62.783964,-70.90604 -61.480311,-70.90604 -60.176658,-70.90604 -58.873005,-70.90604 -57.569352,-70.90604 -56.265699,-70.90604 -54.962046,-70.90604 -53.658393,-70.90604 -52.35474))", "dataset_titles": "Expedition Data; Expedition data of LMG0003A", "datasets": [{"dataset_uid": "002059", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9905"}, {"dataset_uid": "001854", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0106"}, {"dataset_uid": "002688", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0003A", "url": "https://www.rvdata.us/search/cruise/LMG0003A"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to transform three temporary seismometers in the Antarctic Peninsula into semi-permanent stations and to continue basic research using these data. During 1997 and 1998, a network of 11 broadband seismographs in the Antarctic Peninsula region and southernmost Chilean Patagonia were installed and maintained. Data return from this project has been excellent and interesting initial results have been produced. The continued operation of these instruments over a longer time period would be highly beneficial because the number of larger magnitude regional earthquakes is small and so a longer time is needed to acquire data. However, instruments from this project are borrowed from the IRIS-PASSCAL instrument pool and must be returned to PASSCAL in April, 1999. This award provides funds to convert three stations at permanent Chilean bases in the Antarctic to permanent stations, and to continue the seismological investigation of the region for a period of four years. As part of this project, a fourth station, in Chilean Patagonia, will continue to be operated using Washington University equipment. The funding of this project will enable continued collaboration between Washington University and the Universidad de Chile in the operation of these stations, and the data will be forwarded to the IRIS data center as well as to other international seismological collaborators. Mutual data exchanges with other national groups with Antarctic seismology research programs will provide access to broadband data from a variety of other proprietary broadband stations in the region. The data will be used to study the seismicity and upper mantle velocity structure of several complicated tectonic regions in the area, including the South Shetland subduction zone, the Bransfield backarc rift, and diffuse plate boundaries in Patagonia, Drake Passage, and along the South Scotia Ridge. In particular, the operation of these stations over a longer time period will allow a better understanding of the seismicity of the South Shetland Trench, an unusual subduction zone showing very slow subduction of young lithosphere. These seismometers will also be used to record airgun shots during a geophysical cruise in the Bransfield Strait that is being planned by the University of Texas for April, 2000. These data will provide important constraints on the crustal structure beneath the stations, and the improved structural models will enable implementation of more precise earthquake location procedures in support of a seismological understanding of the region.", "east": -54.9187, "geometry": "POINT(-62.91237 -58.873005)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V LMG; R/V NBP", "locations": null, "north": -52.35474, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Wiens, Douglas; Visbeck, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -65.39127, "title": "Acquisition and Operation of Broadband Seismograph Equipment at Chilean Bases in the Antarctic Peninsula Region", "uid": "p0000604", "west": -70.90604}, {"awards": "0440666 Waddington, Edwin", "bounds_geometry": null, "dataset_titles": "Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica", "datasets": [{"dataset_uid": "609473", "doi": "10.7265/N5QR4V2J", "keywords": "Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; WAIS Divide; WAIS Divide Ice Core", "people": "Koutnik, Michelle; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609473"}], "date_created": "Thu, 04 Mar 2010 00:00:00 GMT", "description": "This award supports development of a new modeling approach that will extract information about past snow accumulation rate in both space and time in the vicinity of the future ice core near the Ross-Amundsen divide of the West Antarctic Ice Sheet (WAIS). Internal layers, detected by ice-penetrating radar, are isochrones, or former ice-sheet surfaces that have been buried by subsequent snowfall, and distorted by ice flow. Extensive ice-penetrating radar data are available over the inland portion of the WAIS. Layers have been dated back to 17,000 years before present. The radar data add the spatial dimension to the temporally resolved accumulation record from ice cores. Accumulation rates are traditionally derived from the depths of young, shallow layers, corrected for strain using a local 1-D ice-flow model. Older, deeper layers have been more affected by flow over large horizontal distances. However, it is these deeper layers that contain information on longer-term climate patterns. This project will use geophysical inverse theory and a 2.5D flow-band ice-flow forward model comprising ice-surface and layer-evolution modules, to extract robust transient accumulation patterns by assimilating multiple deeper, more-deformed layers that have previously been intractable. Histories of divide migration, geothermal flux, and surface evolution will also be produced. The grant will support the PhD research of a female graduate student who is a mentor to female socio-economically disadvantaged high-school students interested in science, through the University of Washington Women\u0027s Center. It will also provide a research\u003cbr/\u003eexperience for an undergraduate student, and contribute to a freshman seminar on Scientific Research.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS", "is_usap_dc": true, "keywords": "Ross-Amundsen Divide; FIELD SURVEYS; Internal Layers; Ice Flow Model; West Antarctic Ice Sheet; Accumulation; Glacier; Ice Penetrating Radar; Model; MODELS; Snow Accumulation; GPS; Antarctica; Isochron; Not provided; Snowfall; Radar", "locations": "West Antarctic Ice Sheet; Antarctica; Ross-Amundsen Divide", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Koutnik, Michelle; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e MODELS \u003e MODELS; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Histories of accumulation, thickness and WAIS Divide location from radar layers using a new inverse approach", "uid": "p0000018", "west": null}, {"awards": "0440954 Miller, Molly; 0440919 Isbell, John; 0551163 Sidor, Christian", "bounds_geometry": "POLYGON((159.3 -76.59,159.542 -76.59,159.784 -76.59,160.026 -76.59,160.268 -76.59,160.51 -76.59,160.752 -76.59,160.994 -76.59,161.236 -76.59,161.478 -76.59,161.72 -76.59,161.72 -76.811,161.72 -77.032,161.72 -77.253,161.72 -77.474,161.72 -77.695,161.72 -77.916,161.72 -78.137,161.72 -78.358,161.72 -78.579,161.72 -78.8,161.478 -78.8,161.236 -78.8,160.994 -78.8,160.752 -78.8,160.51 -78.8,160.268 -78.8,160.026 -78.8,159.784 -78.8,159.542 -78.8,159.3 -78.8,159.3 -78.579,159.3 -78.358,159.3 -78.137,159.3 -77.916,159.3 -77.695,159.3 -77.474,159.3 -77.253,159.3 -77.032,159.3 -76.811,159.3 -76.59))", "dataset_titles": "Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617; Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "datasets": [{"dataset_uid": "000124", "doi": "", "keywords": null, "people": null, "repository": "Burke Museum", "science_program": null, "title": "Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617", "url": "http://www.washington.edu/burkemuseum/collections/"}, {"dataset_uid": "600045", "doi": "10.15784/600045", "keywords": "Allan Hills; Antarctica; Paleontology; Sample/collection Description; Sample/Collection Description; Solid Earth", "people": "Miller, Molly", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600045"}], "date_created": "Mon, 12 Oct 2009 00:00:00 GMT", "description": "This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate.\u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.", "east": 161.72, "geometry": "POINT(160.51 -77.695)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.59, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e CARBONIFEROUS \u003e PENNSYLVANIAN; PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN; PHANEROZOIC \u003e MESOZOIC \u003e TRIASSIC", "persons": "Miller, Molly; Sidor, Christian; Isbell, John", "platforms": "Not provided", "repo": "Burke Museum", "repositories": "Burke Museum; USAP-DC", "science_programs": "Allan Hills", "south": -78.8, "title": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "uid": "p0000207", "west": 159.3}, {"awards": "9911617 Blankenship, Donald; 9319379 Blankenship, Donald", "bounds_geometry": null, "dataset_titles": "Antarctic Aerogeophysics Data; Antarctic Subglacial Lake Classification Inventory; RBG - Robb Glacier Survey; SOAR-Lake Vostok Survey airborne radar data; SOAR-Lake Vostok Survey bed elevation data; SOAR-Lake Vostok Survey Gravity data; SOAR-Lake Vostok Survey ice thickness data; SOAR-Lake Vostok survey magnetic anomaly data; SOAR-Lake Vostok Survey surface elevation data", "datasets": [{"dataset_uid": "601300", "doi": "10.1594/IEDA/306568", "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok; Navigation; Radar; SOAR; Subglacial Lakes", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey airborne radar data", "url": "https://www.usap-dc.org/view/dataset/601300"}, {"dataset_uid": "609336", "doi": "10.7265/N5CN71VX", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Subglacial Lake", "people": "Blankenship, Donald D.; Carter, Sasha P.; Holt, John W.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Subglacial Lake Classification Inventory", "url": "https://www.usap-dc.org/view/dataset/609336"}, {"dataset_uid": "601299", "doi": "10.1594/IEDA/306565", "keywords": "Airborne Laser Altimeters; Airborne Laser Altimetry; Airborne Radar; Airplane; Antarctica; Bed Elevation; Bedrock Elevation; Digital Elevation Model; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Lake Vostok; Radar; Radar Echo Sounder; SOAR", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey bed elevation data", "url": "https://www.usap-dc.org/view/dataset/601299"}, {"dataset_uid": "601298", "doi": "10.1594/IEDA/306566", "keywords": "Airborne Altimetry; Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Ice Sheet Elevation; Ice Surface; Lake Vostok; Radar Echo Sounder; SOAR; Surface Elevation", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey surface elevation data", "url": "https://www.usap-dc.org/view/dataset/601298"}, {"dataset_uid": "601297", "doi": "10.1594/IEDA/306567", "keywords": "Airborne Laser Altimeters; Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Sheet; Ice Stratigraphy; Ice Thickness; Ice Thickness Distribution; Lake Vostok; Radar; Radar Altimetry; Radar Echo Sounder; SOAR; Subglacial Lake", "people": "Bell, Robin; Studinger, Michael S.", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey ice thickness data", "url": "https://www.usap-dc.org/view/dataset/601297"}, {"dataset_uid": "601296", "doi": " 10.1594/IEDA/306564", "keywords": "Airborne Magnetic; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Lake Vostok; Magnetic; Magnetic Anomaly; Magnetometer; Potential Field; SOAR; Solid Earth", "people": "Studinger, Michael S.; Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok survey magnetic anomaly data", "url": "https://www.usap-dc.org/view/dataset/601296"}, {"dataset_uid": "601295", "doi": "10.1594/IEDA/306563", "keywords": "Airborne Gravity; Airplane; Antarctica; East Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Lake Vostok; Potential Field; Solid Earth", "people": "Bell, Robin; Studinger, Michael S.", "repository": "USAP-DC", "science_program": null, "title": "SOAR-Lake Vostok Survey Gravity data", "url": "https://www.usap-dc.org/view/dataset/601295"}, {"dataset_uid": "609240", "doi": "", "keywords": "Airborne Radar; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Navigation; Potential Field; SOAR; Solid Earth", "people": "Holt, John W.; Dalziel, Ian W.; Morse, David L.; Blankenship, Donald D.", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Aerogeophysics Data", "url": "https://www.usap-dc.org/view/dataset/609240"}, {"dataset_uid": "601604", "doi": "10.15784/601604", "keywords": "Airborne Radar; Antarctica; Bed Elevation; Geophysics; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Surface Elevation; Ice Thickness; Robb Glacier; Transantarctic Mountains", "people": "Young, Duncan A.; Blankenship, Donald D.; Bell, Robin; Buck, W. Roger", "repository": "USAP-DC", "science_program": null, "title": "RBG - Robb Glacier Survey", "url": "https://www.usap-dc.org/view/dataset/601604"}], "date_created": "Fri, 06 Feb 2009 00:00:00 GMT", "description": "9911617 Blankenship This award, provided jointly by the Antarctic Geology and Geophysics Program, the Antarctic Glaciology Program, and the Polar Research Support Section of the Office of Polar Programs, provides funds for continuation of the Support Office for Aerogeophysical Research (SOAR). From July 1994 to July 2000, SOAR served as a facility to accomplish aerogeophysical research in Antarctica under an agreement between the University of Texas at Austin and the National Science Foundation\u0027s Office of Polar Programs (NSF/OPP). SOAR operated and maintained an aerogeophysical instrument package that consists of an ice-penetrating radar sounder, a laser altimeter, a gravimeter and a magnetometer that are tightly integrated with each other as well as with the aircraft\u0027s avionics and power packages. An array of aircraft and ground-based GPS receivers supported kinematic differential positioning using carrier-phase observations. SOAR activities included: developing aerogeophysical research projects with NSF/OPP investigators; upgrading of the aerogeophysical instrumentation package to accommodate new science projects and advances in technology; fielding this instrument package to accomplish SOAR-developed projects; and management, reduction, and analysis of the acquired aerogeophysical data. In pursuit of 9 NSF-OPP funded aerogeophysical research projects (involving 14 investigators from 9 institutions), SOAR carried out six field campaigns over a six-year period and accomplished approximately 200,000 line kilometers of aerogeophysical surveying over both East and West Antarctica in 377 flights. This award supports SOAR to undertake a one year and 8 month program of aerogeophysical activities that are consistent with continuing U.S. support for geophysical research in Antarctica. - SOAR will conduct an aerogeophysical campaign during the 200/01 austral summer to accomplish surveys for two SOAR-developed projects: \"Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Studies\" (Co-PI\u0027s Bell and Studinger, LDEO); and \"Collaborative Research: Seismic Investigation of the Deep Continental Structure Across the East-West Antarctic Boundary\" (Co-PI\u0027s Weins, Washington U. and Anandakrishnan, U. Alabama). After configuration and testing of the survey aircraft in McMurdo, SOAR will conduct survey flights from an NSF-supported base adjacent to the Russian Station above Lake Vostok and briefly occupy one or two remote bases on the East Antarctic ice sheet. - SOAR will reduce these aerogeophysical data and produce profiles and maps of surface elevation, bed elevation, gravity and magnetic field intensity. These results will be provided to the respective project investigators within nine months of conclusion of field activities. We will also submit a technical manuscript that describes these results to a refereed scientific journal and distribute these results to appropriate national geophysical data centers within approximately 24 months of completion of field activities. - SOAR will standardize all previously reduced SOAR data products and transfer them to the appropriate national geophysical data centers by the end of this grant. - SOAR will convene a workshop to establish a community consensus for future U.S. Antarctic aerogeophysical research. This workshop will be co-convened by Ian Dalziel and Richard Alley and will take place during the spring of 2001. - SOAR will upgrade the existing SOAR in-field quality control procedures to serve as a web-based interface for efficient browsing of many low-level SOAR data streams. - SOAR will repair and/or refurbish equipment that was used during the 2000/01 field campaign. Support for SOAR is essential for accomplishing major geophysical investigations in Antarctica. Following data interpretation by the science teams, these data will provide valuable insights to the structure and evolution of the Antarctic continent.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e IMAGING RADARS \u003e IMAGING RADAR SYSTEMS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LIDAR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e MAGNETIC FIELD/ELECTRIC FIELD INSTRUMENTS \u003e PROTON MAGNETOMETER", "is_usap_dc": true, "keywords": "Ice Sheet; Ice Sheet Elevation; Surface Winds; Snow Temperature; Atmospheric Pressure; Antarctic; West Antarctic Ice Sheet; Surface Temperature Measurements; FIELD INVESTIGATION; Surface Wind Speed Measurements; Subglacial Topography; Atmospheric Humidity Measurements; Not provided; Aerogeophysics; FIELD SURVEYS; GROUND STATIONS; Antarctica; SOAR; Snow Temperature Measurements; West Antarctica; Antarctic Ice Sheet; East Antarctic Plateau", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet; East Antarctic Plateau", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Carter, Sasha P.; Holt, John W.; Blankenship, Donald D.; Morse, David L.; Dalziel, Ian W.", "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 STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)", "uid": "p0000125", "west": null}, {"awards": "0337891 Brook, Edward J.", "bounds_geometry": "POINT(158 -77.666667)", "dataset_titles": "Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica; Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica", "datasets": [{"dataset_uid": "609315", "doi": "10.7265/N5542KJK", "keywords": "Antarctica; Atmosphere; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609315"}, {"dataset_uid": "609314", "doi": "10.7265/N58W3B80", "keywords": "Antarctica; Atmosphere; Byrd Glacier; Byrd Ice Core; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Byrd Ice Core", "title": "Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609314"}], "date_created": "Mon, 05 Nov 2007 00:00:00 GMT", "description": "This award supports the development of a new laboratory capability in the U.S. to measure CO2 in ice cores and investigate millennial-scale changes in CO2 during the last glacial period using samples from the Byrd and Siple Dome ice cores. Both cores have precise relative chronologies based on correlation of methane and the isotopic composition of atmospheric oxygen with counterpart records from Greenland ice cores. The proposed work will therefore allow comparison of the timing of CO2 change, Antarctic temperature change, and Greenland temperature change on common time scales. Such comparisons are vital for evaluating models that explain changes in atmospheric CO2. The techniques being developed will also be available for future projects, specifically the proposed Inland WAIS ice core, for which a highly detailed CO2 record is a major objective, and studies greenhouse and other atmospheric gases and their isotopic composition for which dry extraction is necessary (stable isotopes in CO2, for example). There are many broad impacts of the proposed work. Ice core greenhouse gas records are central contributions of paleoclimatology to research and policy-making concerning global change. The proposed work will enhance those contributions by improving our understanding of the natural cycling of the most important greenhouse gas. It will contribute to the training of a postdoctoral researcher, who will be an integral part of an established research group and benefit from the diverse paleoclimate and geochemistry community at OSU. The PI teaches major and non-major undergraduate and graduate courses on climate and global change. The proposed work will enrich those courses and the courses will provide an opportunity for the postdoctoral researcher to participate in teaching by giving guest lectures. The PI also participates in a summer climate workshop for high school teachers at Washington State University and the proposed work will enrich that contribution. The extraction device that is built and the expertise gained in using it will be resources for the ice core community and available for future projects. Data will be made available through established national data center and the equipment designs will also be made available to other researchers.", "east": 158.0, "geometry": "POINT(158 -77.666667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Core; Climate Change; CO2; Atmospheric Chemistry; Atmospheric CO2; LABORATORY; Not provided; Ice Core Data; Climate; Ice Core Chemistry; Atmospheric Gases; Ice Core Gas Records; GROUND STATIONS; Climate Research", "locations": null, "north": -77.666667, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Ahn, Jinho; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.666667, "title": "Developing Dry Extraction of Ice Core Gases and Application to Millennial-Scale Variability in Atmospheric CO2", "uid": "p0000268", "west": 158.0}, {"awards": "9615502 Harrison, William", "bounds_geometry": "POINT(-148.822 -81.655)", "dataset_titles": "Vertical Strain at Siple Dome, Antarctica, 1999-2002", "datasets": [{"dataset_uid": "609214", "doi": "10.7265/N5HH6H00", "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Siple Dome; Siple Dome Ice Core; Strain; WAISCORES", "people": "Elsberg, Daniel; Pettit, Erin; Zumberge, Mark; Harrison, William; Morack, James; Waddington, Edwin D.", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Vertical Strain at Siple Dome, Antarctica, 1999-2002", "url": "https://www.usap-dc.org/view/dataset/609214"}], "date_created": "Thu, 22 Feb 2007 00:00:00 GMT", "description": "This award is for support for a three year project to measure the vertical strain rate as a function of depth at two sites on Siple Dome Antarctica. Ice flow near a divide such as Siple Dome is unique in that it is predominantly vertical. As a consequence, the component of ice deformation in the vertical direction, the \"vertical strain rate\" is dominant. Its measurement is therefore important for the calibration of dynamic models of ice flow. Two different, relatively new, high resolution systems for its measurement in hot water drilled holes will be employed. The ice flow model resulting from the measurements and flow law determination will be used to interpret the shapes of radar internal layering in terms of the dynamic history and accumulation patterns of Siple Dome over the past 10,000 years. The resulting improved model will also be applied to the interpretation of annual layers thicknesses (to produce annual accumulation rates) and borehole temperatures from the ice core to be drilled at Siple Dome during the 1997/98 field season. The results should permit an improved analysis of the ice core, relative to what was possible at recent coring sites in central Greenland. This is a collaborative project between the University of Alaska, the University of California, San Diego and the University of Washington.", "east": -148.822, "geometry": "POINT(-148.822 -81.655)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e GAUGES \u003e STRAIN GAUGE WHEATSTONE BRIDGE", "is_usap_dc": true, "keywords": "Ice Core Data; GROUND-BASED OBSERVATIONS; Antarctica; USAP-DC; Ice Core; Ice Analysis; Ice Flow; Ice Deformation; Antarctic Ice Sheet; West Antarctic Ice Sheet; Vertical Strain Rate; Ice Sheet; Glaciology; West Antarctica; Ice; Ice Movement", "locations": "Antarctica; Antarctic Ice Sheet; West Antarctica; West Antarctic Ice Sheet", "north": -81.655, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Harrison, William; Morack, James; Pettit, Erin; Zumberge, Mark; Elsberg, Daniel; Waddington, Edwin D.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.655, "title": "Ice Dynamics, the Flow Law, and Vertical Strain at Siple Dome", "uid": "p0000601", "west": -148.822}, {"awards": "0135989 Wilen, Larry", "bounds_geometry": null, "dataset_titles": "Ice Fabric Characteristics: Siple Dome, A Core", "datasets": [{"dataset_uid": "609255", "doi": "10.7265/N54B2Z7V", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Siple Dome; Siple Dome Ice Core", "people": "Wilen, Larry", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Ice Fabric Characteristics: Siple Dome, A Core", "url": "https://www.usap-dc.org/view/dataset/609255"}], "date_created": "Wed, 02 Mar 2005 00:00:00 GMT", "description": "0135989\u003cbr/\u003eWilen\u003cbr/\u003e\u003cbr/\u003eThis is a collaborative proposal by Principal Investigators at the University of Washington and Ohio University. Detailed knowledge about the interactions between micro-structure of ice and its deformation is needed to assess the integrity of stratigraphic layering and the depth-age relationship in ice cores, which is essential for interpreting the paleoclimate record. The Principal Investigators will use micro-structure to study fabric, the orientation distribution of crystal c-axes, and texture, the size and shape of crystals. Numerical modeling of ice deformation is a useful tool in understanding these interactions. Accurate modeling of ice deformation is complicated by factors, such as the fabric, grain size, dynamic recrystallization, stress level, and precise knowledge of initial conditions. For example, ice fabric evolves as the ice is strained and the deformation depends on the fabric. This complicated feedback mechanism must be understood to correctly model ice deformation. In another example, the usual assumption is that the initial fabric is isotropic or random, but there are excellent examples of near-surface ice in the ice cores that are apparently not isotropic. One must know the initial fabric to calculate the deformation rate in ice sheets. Dr. Wilen will combine results of his new automatic fabric analyzer (AFA) with predictions of detailed ice deformation models (Dr. Thorsteinsson) to refine and better constrain such models. The AFA gives new information in thin sections because the precision and number of measured c-axis orientations are greatly improved. The Principal Investigators will analyze existing data and collect new data on fabric and texture from ice cores to address questions regarding near-surface fabric, deformation mechanisms, dynamic recrystallization, and potential sources of layer disturbances. The data will be used to constrain models of fabric evolution and recrystallization processes. With the more refined models, scientists can address different questions and important problems related to ice deformation and ice cores. For example, the recent agreement between the climate records from the Greenland Ice Core Project (GRIP) and Greenland Ice Sheet Project 2 (GISP2) ice cores of the upper-90%, and the disagreement in the lower-10% emphasizes the need to understand and predict the mechanisms and probable depths of disruption in these and future deep ice cores. Evidence suggests that the stratigraphic disturbances arise from the anisotropic nature of ice crystals at a variety of scales. To properly model the deformation of anisotropic ice, the influence of fabric on deformation must be well known.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "GROUND-BASED OBSERVATIONS; Ice Core Data; Siple Dome; Ice Fabric; Ice Core; USAP-DC", "locations": "Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Arctic Natural Sciences", "paleo_time": null, "persons": "Wilen, Larry", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Collaborative Research: Fabric and Texture Characteristics of Micro-Physical Processes in Ice", "uid": "p0000134", "west": null}, {"awards": "9316338 Jacobel, Robert", "bounds_geometry": null, "dataset_titles": "Siple Dome Glaciology and Ice Stream History 1994, 1996", "datasets": [{"dataset_uid": "609085", "doi": "10.7265/N5Z31WJQ", "keywords": "Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Sample/collection Description; Sample/Collection Description; Siple Dome; Siple Dome Ice Core", "people": "Jacobel, Robert", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Siple Dome Glaciology and Ice Stream History 1994, 1996", "url": "https://www.usap-dc.org/view/dataset/609085"}], "date_created": "Fri, 01 Jan 1999 00:00:00 GMT", "description": "9316338 Jacobel This award is for support for a program of glaciological studies of Siple Dome and its surroundings between Ice Streams C and D. The purpose of the work is to characterize the dynamic environment and ice stratigraphy to aid in the assessment of Siple Dome as a potential deep ice core site, and to determine whether the configuration of ice stream flow in the region was different in the past than now. The work involves measurements of the configuration and continuity of internal layers in the ice, using radar echo sounding and determination of velocity field, based on standard GPS surveying. The goals of the work are relevant to understanding the dynamics of the West Antarctic Ice Sheet (WAIS), its past history and its potential future behavior, including possible effects on global sea level. This work is a collaborative project between the University of Washington, the University of Colorado and St. Olaf College. ***", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": true, "keywords": "Siple Dome; Antarctic; Glaciology; Radar; GROUND-BASED OBSERVATIONS; Ice Stream", "locations": "Antarctic; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Jacobel, Robert", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Siple Dome Glaciology and Ice Stream History", "uid": "p0000190", "west": null}]

Help on the Results MapX

This window can be dragged by its header, and can be resized from the bottom right corner.

The Results Map and the Results Table

The Results Map displays the centroids of the geographic bounds of all the results returned by the search.
Results that are displayed in the current map view will be highlighted in blue and brought to the top of the Results Table.
As the map is panned or zoomed, the highlighted rows in the table will update.
If you click on a centroid on the map, it will turn yellow and display a popup with details for that project/dataset - including a link to the landing page. The bounds for the project(s)/dataset(s) selected will be displayed in red. The selected result(s) will be highlighted in red and brought to the top of the table.
The default table sorting order is: Selected, Visible, Date (descending), but this can be changed by clicking on column headers in the table.
Selecting Show on Map for an individual row will both display the geographic bounds for that result on a mini map, and also display the bounds and highlight the centroid on the Results Map.
Clicking the 'Show boundaries' checkbox at the top of the Results Map will display all the bounds for the filtered results.

Defining a search area on the Results Map

If you click on the Rectangle or Polygon icons in the top right of the Results Map, you can define a search area which will be added to any other search criteria already selected.
After you have drawn a polygon, you can edit it using the Edit Geometry dropdown in the search form at the top.
Clicking Clear in the map will clear any drawn polygon.
Clicking Search in the map, or Search on the form will have the same effect.
The returned results will be any projects/datasets with bounds that intersect the polygon.
Use the Exclude project/datasets checkbox to exclude any projects/datasets that cover the whole Antarctic region.

Viewing map layers on the Results Map

Clicking the Layers button - the blue square in the top left of the Results Map - will display a list of map layers you can add or remove from the currently displayed map view.

Search USAP Projects And Datasets

Free Text Search

Repository

Title (free text)

Science Program

Person

Award

NSF Funding Program

Keyword

Spatial Bounds of Data Use the Results Map below to draw a polygon over the required search area, or edit the WKT geometry here:

Any WKT polygon, with longitudes in a 0-360 ° range. Example: Ross Sea is between 160 and 210. Read about the WKT format here.

Exclude projects that cover the whole Antarctic from map-based search

45 record(s) found

Older retrieved projects from AMD. Warning: many have incomplete information.

To sort the table of search results, click the header of the column you wish to search by. To sort by multiple columns, hold down the shift key whilst selecting the sort columns in order.

Project Title/Abstract/Map

NSF Award(s)

Date Created

PIs / Scientists

Dataset Links and Repositories

OPP-PRF: Remote Pathways of Ocean Heat Transport toward the Antarctic Ice Sheet

2420258

2025-07-07

Prend, Channing

No dataset link provided

Antarctic Ice Sheet (AIS) melt is a leading contributor to global sea level rise, which affects coastal communities around the world. Therefore, understanding the mechanisms that control the location and magnitude of melting is crucial to plan for the effects of climate change. The primary heat source causing AIS melt is the ocean, since air temperatures in the Antarctic currently are currently often too cold to melt the glaciers from above. Therefore, ocean currents, which carry heat from the open ocean to the ice sheet, play a key role in determining trends and variability of ice melt in space and time. Previous work on ocean-driven melting of Antarctica have focused on the ocean circulation close to the ice sheets. However, recent modeling studies suggest that changes in ocean currents hundreds of kilometers offshore could have cascading effects on the heat supply to the ice sheet. This project will use observations collected by robotic floats and a climate model to investigate the mechanisms that relate ocean circulation far offshore to ice sheet melt. Characterizing these processes is necessary to improve sea level rise projections. The water mass responsible for driving much of the AIS melt is called Circumpolar Deep Water (CDW) and originates in the open ocean within the Antarctic Circumpolar Current (ACC). While many previous studies have examined cross-shelf heat fluxes, few have analyzed the circumpolar pathways of CDW from the ACC to the continental slope and their influence on AIS mass loss. Importantly, these remote processes control the offshore reservoir of CDW that precedes on-shelf heat transport. This project will quantify the pathways of CDW from its origin in the ACC to the Antarctic continental slope and determine the physical mechanisms that govern the variability of these pathways. Researchers will conduct a series of Lagrangian particle release experiments in a data-assimilating state estimate of the Southern Ocean. Analyzing the trajectories will allow them to statistically constrain regional, seasonal, and interannual variability in the remote pathways of ocean heat transport toward the AIS. The Lagrangian experiments will be complemented by autonomous profiling float data from the West Antarctic. These observations will enable the validation of the model and further probe the physical mechanisms of onshore heat transport. Together, these results will help discern the controls on AIS melting, which has implications for numerous climate feedbacks.

Wave Glider Observations of Surface Fluxes and Mixed-layer Processes in the Southern Ocean

1558448
1853291

2025-01-15

Girton, James; Thomson, Jim

Expedition Data of LMG1909	R2R
Data from 2019 WG launch cruise LMG1909	R2R
Expedition data of LMG1612	R2R
LMG2002 Expedtition Data	R2R
Wave Glider Data from 2016/17 Mission	University of Washington
Data from 2020 WG recovery cruise LMG2002	R2R
APL-UW Southern Ocean Wave Glider Data from 2019/20 Mission	USAP-DC
Expedition Data	R2R
Data from 2017 WG recovery cruise LMG1703	R2R
Data from 2016 WG launch cruise LMG1612	R2R

EAGER: Metabolomics Analysis of Archival Marine Invertebrates

2341344

2023-09-15

Baker, Bill

Orbitrap data from archived marine invertebrates

USAP-DC

Non-technical project description Museums of natural history, such as the Smithsonian National Museum of Natural History (NMNH) in Washington, D.C., are repositories for, among other things, biological specimens. Specimens stored at the NMNH were obtained over many decades and across the globe, resulting in what is currently a treasure trove of biological and chemical information. Chemical compounds (metabolites) found in the tissues of, for example, marine invertebrates, can record the organism’s response to a changing environment. This project seeks to establish a strategy for analyzing these compounds in Antarctic marine invertebrates held in the NMNH. These organisms are especially valuable for studies of their metabolites as such information will contribute to our understanding of the history of the polar environment and how organisms are able to adapt to extreme habitats. Further, studies of these rare and difficult to obtain metabolites have broad impacts in biotechnology and human health. Technical description of the project This project seeks to develop a workflow for the analysis of metabolites in archival marine invertebrate specimens held in the Smithsonian National Museum of Natural History (NMNH). Recent advances in mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy, both instrumental as well as analysis platforms, enable the detection and annotation of chemical structures in these otherwise difficult to obtain metabolites. In particular, NMR strategy (Pure Shift NMR) will be implemented to increase sensitivity toward these sample-limited analytes. Further, the workflow will be applied in an analysis of storage methods used by the NMNH with the aim of understanding how best to preserve specimens for future metabolomics analyses. With an optimized workflow established, additional applications to inform our understanding of adaptation and (cryptic) speciation in the extreme habitats found in Antarctica are possible. 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.

Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets

1744649

2022-08-02

Christianson, Knut; Hoffman, Andrew; Holschuh, Nicholas

Hercules Dome High-Frequency Impulse Ice-Penetrating Radar Data	USAP-DC
Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets	USAP-DC
ITASE Impulse Radar Hercules Dome to South Pole	USAP-DC
Hercules Dome ApRES Data	USAP-DC
Hercules Dome Ice-Penetrating Radar Swath Topographies	USAP-DC

The response of the Antarctic ice sheet to climate change is a central issue in projecting global sea-level rise. While much attention is focused on the ongoing rapid changes at the coastal margin of the West Antarctic Ice Sheet, obtaining records of past ice-sheet and climate change is the only way to constrain how an ice sheet changes over millennial timescales. Whether the West Antarctic Ice Sheet collapsed during the last interglacial period (~130,000 to 116,000 years ago), when temperatures were slightly warmer than today, remains a major unsolved problem in Antarctic glaciology. Hercules Dome is an ice divide located at the intersection of the East Antarctic and West Antarctic ice sheets. It is ideally situated to record the glaciological and climatic effects of changes in the West Antarctic Ice Sheet. This project will establish whether Hercules Dome experienced major changes in flow due to changes in the elevation of the two ice sheets. The project will also ascertain whether Hercules Domes is a suitable site from which to recover climate records from the last interglacial period. These records could be used to determine whether the West Antarctic Ice Sheet collapsed during that period. The project will support two early-career researchers and train students at the University of Washington. Results will be communicated through outreach programs in coordination the Ice Drilling Project Office, the University of Washington's annual Polar Science Weekend in Seattle, and art-science collaboration. This project will develop a history of ice dynamics at the intersection of the East and West Antarctic ice sheets, and ascertain whether the site is suitable for a deep ice-coring operation. Ice divides provide a unique opportunity to assess the stability of past ice flow. The low deviatoric stresses and non-linearity of ice flow causes an arch (a "Raymond Bump") in the internal layers beneath a stable ice divide. This information can be used to determine the duration of steady ice flow. Due to the slow horizontal ice-flow velocities, ice divides also preserve old ice with internal layering that reflects past flow conditions caused by divide migration. Hercules Dome is an ice divide that is well positioned to retain information of past variations in the geometry of both the East and West Antarctic Ice Sheets. This dome is also the most promising location at which to recover an ice core that can be used to determine whether the West Antarctic Ice Sheet collapsed during the last interglacial period. Limited ice-penetrating radar data collected along a previous scientific surface traverse indicate well-preserved englacial stratigraphy and evidence suggestive of a Raymond Bump, but the previous survey was not sufficiently extensive to allow thorough characterization or determination of past changes in ice dynamics. This project will conduct a dedicated survey to map the englacial stratigraphy and subglacial topography as well as basal properties at Hercules Dome. The project will use ground-based ice-penetrating radar to 1) image internal layers and the ice-sheet basal interface, 2) accurately measure englacial attenuation, and 3) determine englacial vertical strain rates. The radar data will be combined with GPS observations for detailed topography and surface velocities and ice-flow modeling to constrain the basal characteristics and the history of past ice flow. 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.

Collaborative Research: Modeling ice-ocean interaction for the rapidly evolving ice shelf cavities of Pine Island and Thwaites glaciers, Antarctica

1643285
1643174

2022-05-13

Joughin, Ian; Dutrieux, Pierre; Padman, Laurence; Springer, Scott

icepack	GitHub
Pine Island Basin Scale Model	GitHub
Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier	Uni. Washington ResearchWorks Archive
Beta Version of Plume Model	GitHub

The West Antarctic Ice Sheet contains enough ice to raise global sea levels by 3-4 meters. Ice-sheet volume falls, and sea level increases, when more ice is lost to the ocean by glacier flow than is replaced by snowfall. Glacier speed is reduced when ice shelves, which are the floating extensions of the ice sheets, are present. Processes that affect ice shelf thickness and extent therefore influence the rates of grounded ice loss and sea-level rise. West Antarctica is currently losing ice, at an accelerating rate, with most loss occurring in the Amundsen Sea region via discharge from Pine Island and Thwaites glaciers. This loss was initiated by increased circulation of relatively warm ocean water beneath these glacier's ice shelves, causing them to thin by melting. However, this melting also depends on how the changing shape of the ice shelves affects the ocean circulation beneath them and the speeds of the grounded glaciers upstream. Limited understanding of these processes leads to uncertainties in estimates of future ice loss. This interdisciplinary project brings together glaciologists and oceanographers from three US institutions to study the interactions between changing glacier flow, ice shelf shape and extent, and ocean circulation. Data and numerical models will be used to identify the key processes that determine how rapidly this region can shed ice. The project team will train postdocs and graduate students in cutting-edge modeling techniques, and educate the public about Antarctic ice loss through talks, school science fairs, and Seattle Science Center's annual Polar Science Weekend. The project team will conduct simulations, using a combination of ice-sheet and ocean models, to reduce uncertainties in projected ice loss from Pine Island and Thwaites glaciers by: (i) assessing how ice-shelf melt rates will change as the ice-shelf cavities evolve through melting and grounding-line retreat, and (ii) improving understanding of the sensitivity of sub-shelf melt rates to changes in ocean state on the nearby continental shelf. These studies will reduce uncertainty on ice loss and sea-level rise estimates, and lay the groundwork for development of future fully-coupled ice-sheet/ocean models. The project will first develop high-resolution ice-shelf-cavity circulation models driven by modern observed regional ocean state and validated with estimates of melt derived from satellite observations. Next, an ice-flow model will be used to estimate the future grounding retreat. An iterative process with the ocean-circulation and ice-flow models will then simulate melt rates at each stage of retreat. These results will help assess the validity of the hypothesis that unstable collapse of the Amundsen Sea sector of West Antarctica is underway, which was based on simplified models of melt rate. These models will also provide a better understanding of the sensitivity of melt to regional forcing such as changes in Circumpolar Deep Water temperature and wind-driven changes in thermocline height. Finally, several semi-coupled ice-ocean simulations will help determine the influence of the ocean-circulation driven melt over the next several decades. These simulations will provide a much-improved understanding of the linkages between far-field ocean forcing, cavity circulation and melting, and ice-sheet response.

Weddell Gyre Mean Circulation and Eddy Statistics from Floats

2148517

2022-03-25

Hancock, Cathrine; Speer, Kevin

Trajectories for APEX floats 9223 and 9224 from acoustic tracking using artoa4argo, Mar 2022-Feb 2023	USAP-DC
Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre	USAP-DC

The Weddell Gyre is one of the major components of the Southern Ocean circulation system, linking heat and carbon fluxes in the Antarctic Circumpolar Current to the continental margins. Water masses entering the Weddell Gyre are modified as they move in a great circular route around the gyre margin and change through processes involving air-sea-cryosphere interactions as well as through ocean eddies that mix properties across the gyre boundaries. Some of the denser water masses exit the gyre through pathways along the northern boundary, and ultimately ventilate the global deep ocean as Antarctic Bottom Water. While in-situ and satellite observations, as well as computer modeling efforts, provide estimates of the large-scale average flow within the gyre, details of the smaller-scale, or "mesoscale" eddy flow remain elusive. The proposed research will quantify mixing due to mesoscale eddies within the Weddell Gyre, as well as the transport of incoming deep water from the northeast, thought to be a result of transient eddies. Since the Weddell Gyre produces source water for about 40% of Antarctic Bottom Water formation, understanding the dynamics in this region helps to identify causes of documented changes in global bottom waters. This in turn, will give insight into how climate change is affecting global oceans, through modification of dense polar waters and Antarctic Bottom Water characteristics. This project aims to track 153 RAFOS-enabled Argo floats in the ice-covered regions of the Weddell Gyre. The resultant tracks along with all available Argo and earlier float data will be used to calculate Eulerian and Lagrangian means and eddy statistics for the Weddell Gyre. The study will link RAFOS tracks with Argo profiles under ice, allowing one to characterize the importance of eddies in water column modification at critical ice-edge boundaries and leads. With RAFOS tracks near the northeastern limit of the gyre, the project will investigate the eddy-driven processes of incoming Circumpolar Deep Water, to understand better the mechanisms and volume fluxes involved. Previous work shows that a large fraction of the mean circulation in the southern and western limits of the gyre, where it contacts the Antarctic continent, occurs in a narrow boundary layer above the slope. The research here will integrate this flow structure into a complete interior and boundary layer mean circulation synthesis. The findings and products from the proposed work will improve the positioning of Argo profiles in the polar regions, which would allow for more accurate climatological maps and derived quantities. Estimates of meso-scale mixing may serve as a foundation for the development of new parameterization schemes employed in climate models, as well as local and global ocean circulation models in polar regions. 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.

CAREER: Coastal Antarctic Snow Algae and Light Absorbing Particles: Snowmelt, Climate and Ecosystem Impacts

2046240

2021-09-10

Khan, Alia

No dataset link provided

________________________________________________________________________________________________ Part I: Non-technical Summary The Antarctic Peninsula is one of the most rapidly warming regions on the planet. This 5-yr time-series program will build on an ongoing international collaboration with scientists from the Chilean Antarctic Program to evaluate the role of temperature, light absorbing particles, snow-algae growth, and their radiative forcing effects on snow and ice melt in the Western Antarctic Peninsula. There is strong evidence that these effects may be intensifying due to a warming climate. Rising temperatures can increase the growth rate of coastal snow algae as well as enhance the input of particles from sources such as the long-range transport of black carbon to the Antarctic continent from intensifying Southern Hemisphere wildfire seasons. Particle and algae feedbacks can have immediate local impacts on snow melt and long-term regional impacts on climate because reduced snow cover alters how the Antarctic continent interacts with the rest of the global climate. A variety of ground-based and remote sensing data collected across multiple spatial scales will be used. Ground measurements will be compared to satellite imagery to develop novel computer algorithms to map ice algal bloom effects under changing climates. The project is expected to fundamentally advance knowledge of the spatial and temporal snow algae growing season, which is needed to quantify impacts on regional snow and ice melt. The program also has a strong partnership with the International Association of Antarctic Tour Operators to involve cruise passengers as citizen scientists for sample collection. Antarctic research results will be integrated into undergraduate curricula and research opportunities through studies to LAPs and snow algae in the Pacific Northwest. The PI will recruit and train a diverse pool of students in cryosphere climate related research methods on Mt. Baker in Western Washington. Trained undergraduate will then serve as instructors for a local Snow School that takes middle school students to Mt. Baker to learn about snow science. Resulting datasets from Antarctica and Mt. Baker will be used in University classes to explore regional effects of climate change. Along with enhancing cryosphere-oriented place-based undergraduate field courses in the Pacific Northwest, the PI will recruit and train a diverse pool of undergraduate students to serve as instructors for the Mt. Baker Snow School program. This award will advance our understanding of cryosphere-climate feedbacks, which are likely changing and will continue to evolve in a warming world, while also increasing under-represented student engagement in the polar geosciences. Part 2: Technical Summary Rapid and persistent climate warming in the Western Antarctic Peninsula is likely resulting in intensified snow-algae growth and an extended bloom season in coastal areas. Similarly, deposition of light absorbing particles (LAPs) onto Antarctica cryosphere surfaces, such as black carbon from intensifying Southern Hemisphere wildfire seasons, and dust from the expansion of ice-free regions in the Antarctic Peninsula, may be increasing. The presence of snow algae blooms and LAPs enhance the absorption of solar radiation by snow and ice surfaces. This positive feedback creates a measurable radiative forcing, which can have immediate local and long-term regional impacts on albedo, snow melt and downstream ecosystems. This project will investigate the spatial and temporal distribution of snow algae, black carbon and dust across the Western Antarctica Peninsula region, their response to climate warming, and their role in regional snow and ice melt. Data will be collected across multiple spatial scales from in situ field measurements and sample collection to imagery from ground-based photos and high resolution multi-spectral satellite sensors. Ground measurements will inform development and application of novel algorithms to map algal bloom extent through time using 0.5-3m spatial resolution multi-spectral satellite imagery. Results will be used to improve snow algae parameterization in a new version of the Snow Ice Aerosol Radiation model (SNICARv3) that includes bio-albedo feedbacks, eventually informing models of ice-free area expansion through incorporation of SNICARv3 in the Community Earth System Model. Citizen scientists will be mentored and engaged in the research through an active partnership with the International Association of Antarctic Tour Operators that frequently visits the region. The cruise ship association will facilitate sampling to develop a unique snow algae observing network to validate remote sensing algorithms that map snow algae with high-resolution multi-spectral satellite imagery from space. These time-series will inform instantaneous and interannual radiative forcing calculations to assess impacts of snow algae and LAPs on regional snow melt. Quantifying the spatio-temporal growing season of snow algae and impacts from black carbon and dust will increase our ability to model their impact on snow melt, regional climate warming and ice-free expansion in the Antarctic Peninsula region. 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.

A non-amniote perspective on the recovery from the end-Permian extinction at high latitudes: paleobiology of Early Triassic temnospondyls from Antarctica

1947094

2021-06-30

Sidor, Christian

No dataset link provided

Non-technical Abstract Around 252 million years ago, a major mass extinction wiped out over 90% of species on Earth. Coincident with this extinction, the Antarctic portion of the supercontinent of Pangea transitioned to a warmer climatic regime devoid of a permanent ice cap. Compared to lower latitudes, relatively little is known about the survivors of the extinction in Antarctica, although it has been hypothesized that the continents more polar location shielded it from the worst of the extinctions effects. As the result of a NSF-sponsored deep field camp in 2017/2018, a remarkable collection of vertebrate fossils was discovered in the rocks of the Shackleton Glacier region. This collection includes the best preserved and most complete materials of fossil amphibians ever recovered from Antarctica, including two previously undescribed species. This grant supports one postdoctoral researcher with expertise in fossil amphibians to describe and interpret the significance of these fossils, including their identification, relationships, and how they fit into the terrestrial ecosystem of Antarctica and other southern hemisphere terrestrial assemblages in light of the major reorganization of post-extinction environments. Historical collections of fossil amphibians will also be reviewed as part of this work. Undergraduate students at the University of Washington will be actively involved as part of this research and learn skills like hard tissue histology and CT data manipulation. Public engagement in Antarctic science will be accomplished at the University of Washington Burke Museum, which is the Washington State museum of natural history and culture. Specifically, a new exhibit on Antarctic amphibians will be developed as part of the paleontology gallery, which sees over 100,000 visitors per year. Technical Abstract This two-year project will examine the evolution of Triassic temnospondyls based on a remarkable collection of fossils recently recovered from the Shackleton Glacier region of Antarctica. Temnospondyls collected from the middle member of the Fremouw Formation are part of the first collection of identifiable tetrapod fossils from this stratigraphic interval. Thorough anatomical description and comparisons of these fossils will add new faunal information and also aid in determining if this horizon is Early or Middle Triassic in age. Exquisitely preserved temnospondyl material from the lower Fremouw Formation will permit more precise identification than previously possible and will provide insights into the earliest stages of their radiation in the extinction recovery interval. Overall, the Principal Investigator and Postdoctoral Researcher will spearhead an effort to revise the systematics of the Antarctic members of Temnospondyli and properly contextualize them in the framework of Triassic tetrapod evolution. The research team will also take advantage of the climate-sensitive nature of fossil amphibians to better understand patterns of seasonality at high-latitudes during the early Mesozoic by subjecting selected fossils to histological analysis. Preliminary data suggest that temnospondyls were exceptionally diverse and highly endemic immediately after the end-Permian extinction, when compared to their distribution before and after this interval. If confirmed, this macroevolutionary pattern could be used to predict the response of modern amphibians to future climate perturbations. Overall, this research will provide new insights into the vertebrate fauna of the Fremouw Formation, as well as shed light on the evolution of terrestrial ecosystems in southern Pangea in the wake of the Permian-Triassic mass extinction. As part of the broader impacts, the research team will help to develop an exhibit featuring some of the best preserved fossils from Antarctica to explain to the public how paleontologists use fossils and rocks to understand past climates like the Triassic 'hot-house' world that lacked permanent ice caps at the poles. 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.

Collaborative Research: The Impact of Impurities and Stress State on Polycrystalline Ice Deformation

1851022
1851094

2021-06-28

Baker, Ian; Fudge, T. J.

EPICA Dome C Sulfate Data 7-3190m	USAP-DC
Volcanic Widths in Dome C Interglacials and Glacials	USAP-DC
Code for calculating mean gradient for EDC sulfate data	USAP-DC
Forward Diffusion Model used to calculate widening of volcanic layer widths	USAP-DC

The ice of the polar ice sheets is among the purest substances on Earth, yet the small amount of impurities --such as acids-- are important to how the ice flows and what can be learned from ice cores about past climate. The goal of this project is to understand the role of such acids on the deformation of polycrystalline ice by comparing the deformation behavior of pure and sulfuric acid-doped samples. Sulfuric acid was chosen both because of its importance for interpreting past climate and because it can lead to water veins in ice at low temperatures. This work will focus on the location, movement, and impact of acids in polycrystalline ice that are more complex than in single crystals of ice. By deforming samples and performing microstructural characterization, the role of acids on deformation rate, grain evolution, and the movement of the acids themselves, will be assessed. The work will lead to the education of a Ph.D. student at Dartmouth College, introduce undergraduate students to research at both the University of Washington and Dartmouth College. Despite the ubiquitous use of the constitutive relation for ice commonly referred to as "Glen's Flow Law", significant uncertainty exists particularly with regard to the role of impurities and the development of oriented fabrics. The aim of this project is to improve the constitutive relationship for ice by performing deformation tests and microstructural characterization of pure and sulfuric acid-doped ice. The project will focus on sulfuric acid's impact on ice viscosity, fabric evolution, and diffusivity. Sulfuric acid can have both direct and indirect effects on the mechanical properties of polycrystalline ice. The direct effects change the dislocation velocity and/or density, and the indirect effects change the grain size and fabric. The complexity and interaction of these effects means that it is not possible to understand the effects of sulfuric acid by simply examining ice core specimens. In this project, the team will deform four types of ice: lab-grown ice samples doped with similar-to-natural concentrations of sulfuric acid, lab-grown high-purity ice, layered doped and pure ice, and natural ice from Antarctic ice cores. Deformation will be performed in both uniaxial compression and simple shear. The addition of simple shear tests is critical for relating the laboratory-observed deformation behavior to the behavior of polar ice sheets where the shear strain dominates ice motion in basal ice. After deformation to strains from 5 percent up to 25 percent, the microstructural development will be assessed with methods including a variety of scanning electron microscope techniques, Raman microscopy, synchrotron-based Nano-X-ray fluorescence, and ion chromatography. These analysis techniques will allow the determination of 1) the segregation and movement of impurities, 2) the rate of grain-boundary migration, 3) the number of recrystallized grains; and 4) the full orientation of the ice crystals. The results will enable both microstructural modeling of the effects of sulfuric acid and numerical modeling of diffusion in ice cores. The net result will be a better understanding of ice deformation that improves ice-core interpretation and ice-sheet modeling. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems

1543344

2021-05-18

Soreghan, Gerilyn; Elwood Madden, Megan

Data and metadata for "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems"

USAP-DC

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.

Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow

1643353
1643301

2021-02-17

Christianson, Knut; Gerbi, Christopher; Campbell, Seth; Vel, Senthil

South Pole Lake GNSS	USAP-DC
South Pole Lake ApRES Radar	USAP-DC
SeidarT	GitHub
ImpDAR: an impulse radar processor	GitHub
South Pole Lake: ground-based ice-penetrating radar	Uni. Washington ResearchWorks Archive

Gerbi/1643301 This award supports a project to develop software that will allow researchers considering seismic or radar field surveys to test, ahead of time, whether the data they plan to collect will have sufficient resolution to measure the natural variations in the mechanical properties of ice, which determine the response of flowing ice to changing climatic conditions. The mechanical properties of ice depend largely on the temperature and the orientation of the crystals that make up the ice. The most accurate method for measuring ice crystal orientation and temperature is through drilling and direct analysis of an ice core. However, this method is very costly, time-consuming, and limited in spatial coverage. Geophysical techniques, such as seismic and radar, can cover much more area, but we have little knowledge about the practical limitations of these techniques as they relate to calculating mechanical properties. This project addresses that knowledge gap through construction of a computational toolbox that will allow accurate assessment of the ability of geophysical surveys to image crystal orientation and ice temperature. Researchers can then use these tools to adjust the field survey plans to maximize the return on investment. By working to improve the efficiency and effectiveness of future geophysical work related to glacial flow, this proposal will improve scientists? ability to quantify sea-level variations within the larger context of climate change. The project includes building new user-friendly, publicly accessible software and instructional modules. The work will provide training for graduate and undergraduate students, who will play a role in research and develop instructional materials. Ice viscosity, the resistance of ice to flow, exerts significant control over ice velocity. Therefore, mapping ice viscosity is important for understanding the current and future behavior of glaciers and ice sheets. To do so, scientists must determine the temperature and crystal orientation fabric throughout the ice. Seismic and radar techniques can survey large areas quickly, and thus are promising, yet not fully tested, methods to efficiently measure the thermal and mechanical structure of flowing ice. As part of this project, scientists will develop and use a computational framework to quantify the degree to which seismic and radar techniques can resolve the crystal orientation fabric and temperature of streaming ice, and then test how sensitive ice flow is to the attendant uncertainty. To meet these goals, a numerical toolbox will be built which will allow the glacier/ice stream geometry and physical properties (temperature, crystal orientation fabric, density and acidity) to be varied. The toolbox will be capable of both creating synthetic radar and seismic profiles through forward modeling and inverting synthetic profiles to allow evaluation of how well geophysical techniques can image the original thermal and mechanical structure. These simulated radar and seismic data will allow scientists to better quantify the influence of the variability in mechanical properties of the ice on flow velocities and patterns. The results of this work will guide planning for future field campaigns, making them more effective and efficient. This project does not require fieldwork in the Antarctic.

Collaborative Research: Sea ice as a driver of Antarctic benthic macroalgal community composition and nearshore trophic connectivity

1744584
1744570
1744550
1744602

2020-06-04

Amsler, Charles; McClintock, James; Iken, Katrin; Galloway, Aaron; Klein, Andrew

Computed fetch for project study sites	USAP-DC
Initial release of code and data associated with Whippo et al. (2024) Fatty acid profiles and stable isotope composition of Antarctic macroalgae: A baseline for a combined biomarker approach in food web studies.	Zendo
Latitude and longitude data for project study sites	USAP-DC
Underwater transect videos used for community analyses	USAP-DC
Underwater video transect community analysis data	USAP-DC
VIIRS KD(490) diffuse attenuation coefficients for study sites	USAP-DC
Average global horizontal solar irradiance at study sites	USAP-DC
Sea Ice Concentration Timeseries for study sites	USAP-DC
Gridded sea ice concentrations from National Ice Center (NIC) Charts 2014-2019 for Western Antarctic Peninsula	USAP-DC
Five year mean annual and summer sea ice concentration grids for the Western Antarctic Peninsula from AMSR2, National Ice Center Charts and the Sea Ice Index	USAP-DC
Modelled Solar Irradiance for Western Antarctic Pennisula	USAP-DC
Carbon and nitrogen isotope data along a gradient at the Antarctic Peninsula	USAP-DC
Landsat Sea Ice/Cloud classifications surrounding project study sites	USAP-DC
Macroalgal species collected along horizontal transect components	USAP-DC
Chemical composition data for Desmarestia menziesii	USAP-DC
Chemical composition data for Himantothallus grandifolius	USAP-DC
Chemical composition data for Iridaea	USAP-DC
Chemical composition data for Sarcopeltis antarctica	USAP-DC
LMG1904 expedition data	R2R

The western Antarctic Peninsula has become a model for understanding cold water communities and how they may be changing in Antarctica and elsewhere. Brown macroalgae (seaweeds) form extensive undersea forests in the northern portion of this region where they play a key role in providing both physical structure and a food (carbon) source for shallow water communities. Yet between Anvers Island (64 degrees S latitude) and Adelaide Island (67 S latitude) these macroalgae become markedly less abundant and diverse. This is probably because the habitat to the south is covered by more sea ice for a longer period, and the sea ice reduces the amount of light that reaches the algae. The reduced macroalgal cover undoubtedly impacts other organisms in the food web, but the ways in which it alters sea-floor community processes and organization is unknown. This project will quantitatively document the macroalgal communities at multiple sites between Anvers and Adelaide Islands using a combination of SCUBA diving, video surveys, and algal collections. Sea ice cover, light levels, and other environmental parameters on community structure will be modelled to determine which factors have the largest influence. Impacts on community structure, food webs, and carbon flow will be assessed through a mixture of SCUBA diving and video surveys. Broader impacts include the training of graduate students and a postdoctoral researcher, as well as numerous informal public education activities including lectures, presentations to K-12 groups, and a variety of social media-based outreach. Macroalgal communities are more abundance and diverse to the north along the Western Antarctic Peninsula, perhaps due to the greater light availability that is associated with shorter period of sea-ice cover. This project will determine the causes and community level consequence of this variation in algal community structure. First, satellite data on sea ice extent and water turbidity will be used to select study sites between 64 S and 69 S where the extent of annual sea ice cover is the primary factor influencing subsurface light levels. Then, variations in macroalgal cover across these study sites will be determined by video line-transect surveys conducted by SCUBA divers. The health, growth, and physiological status of species found at the different sites will be determined by quadrat sampling. The relative importance of macroalgal-derived carbon to the common invertebrate consumers in the foodweb will be assessed with stable isotope and fatty acid biomarker techniques. This will reveal how variation in macroalgal abundance and species composition across the sea ice cover gradient impacts sea floor community composition and carbon flow throughout the food web. In combination, this work will facilitate predictions of how the ongoing reductions in extent and duration of sea ice cover that is occurring in the region as a result of global climate change will impact the structure of nearshore benthic communities. 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.

Ancient landscape-active Surfaces: Periglacial Hyperinflation in soils of Beacon Valley, Antarctica

1341680

2019-11-21

Sletten, Ronald S.; Stone, John

Chemical and physical characterization of Beacon Valley and Victoria Valley permafrost cores

USAP-DC

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 meter/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. Broader impacts: 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.

Formation and Characteristics of Brine-rich Water in the Dry Valleys, Antarctica

1643550

2019-11-21

Sletten, Ronald S.

Timelapse photography of Don Juan Pond and surrounding basin

USAP-DC

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. 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.

Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole

1443105

2019-11-17

Steig, Eric J.; White, James

SP19 Gas Chronology	USAP-DC
Continuous-flow measurements of the complete water isotope ratios (D/H, 17O/16O, 18O/16) from the South Pole ice core	USAP-DC
South Pole Ice Core Holocene Major Ion Dataset	USAP-DC
South Pole high resolution ice core water stable isotope record for dD, d18O	USAP-DC
South Pole Ice Core Sea Salt and Major Ions	USAP-DC
Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)	USAP-DC

This project will develop a record of the stable-isotope ratios of water from an ice core at the South Pole, Antarctica. Water-isotope ratio measurements provide a means to determine variability in temperature through time. South Pole is distinct from most other locations in Antarctica in showing no warming in recent decades, but little is known about temperature variability in this location prior to the installation of weather stations in 1957. The measurements made as part of this project will result in a much longer temperature record, extending at least 40,000 years, aiding our ability to understand what controls Antarctic climate, and improving projections of future Antarctic climate change. Data from this project will be critical to other investigators working on the South Pole ice core, and of general interest to other scientists and the public. Data will be provided rapidly to other investigators and made public as soon as possible. This project will obtain records of the stable-isotope ratios of water on the ice core currently being obtained at South Pole. The core will reach a depth of 1500 m and an age of 40,000 years. The project will use laser spectroscopy to obtain both an ultra-high-resolution record of oxygen 18/16 and deuterium-hydrogen ratios, and a lower-resolution record of oxygen 17/16 ratios. The high-resolution measurements will be used to aid in dating the core, and to provide estimates of isotope diffusion that constrain the process of firn densification. The novel 17/16 measurement provides additional constraints on the isotope fractionation due to the temperature-dependent supersaturation ratio, which affects the fractionation of water during the liquid-solid condensate transition. Together, these techniques will allow for improved accuracy in the use of the water isotope ratios as proxies for ice-sheet temperature, sea-surface temperature, and atmospheric circulation. The result will be a record of decadal through centennial and millennial scale climate change in a climatically distinct region in East Antarctica that has not been previously sampled by deep ice coring. The project will support a graduate student who will be co-advised by faculty at the University of Washington and the University of Colorado, and will be involved in all aspects of the work.

Collaborative Research: A 1500m Ice Core from South Pole

1142646
1142517
1141839

2019-10-30

Twickler, Mark; Souney, Joseph Jr.; Aydin, Murat; Steig, Eric J.

South Pole Ice Core Sea Salt and Major Ions	USAP-DC
South Pole Ice Core Holocene Major Ion Dataset	USAP-DC
SP19 Gas Chronology	USAP-DC
South Pole Ice Core (SPICEcore) SPC14 Core Quality Versus Depth	USAP-DC
South Pole ice core (SPC14) discrete methane data	USAP-DC
Temperature, accumulation rate, and layer thinning from the South Pole ice core (SPC14)	USAP-DC

1142517/Saltzman This proposal requests support for a project to drill and recover a new ice core from South Pole, Antarctica. The South Pole ice core will be drilled to a depth of 1500 m, providing an environmental record spanning approximately 40 kyrs. This core will be recovered using a new intermediate drill, which is under development by the U.S. Ice Drilling Design and Operations (IDDO) group in collaboration with Danish scientists. This proposal seeks support to provide: 1) scientific management and oversight for the South Pole ice core project, 2) personnel for ice core drilling and core processing, 3) data management, and 3) scientific coordination and communication via scientific workshops. The intellectual merit of the work is that the analysis of stable isotopes, atmospheric gases, and aerosol-borne chemicals in polar ice has provided unique information about the magnitude and timing of changes in climate and climate forcing through time. The international ice core research community has articulated the goal of developing spatial arrays of ice cores across Antarctica and Greenland, allowing the reconstruction of regional patterns of climate variability in order to provide greater insight into the mechanisms driving climate change. The broader impacts of the project include obtaining the South Pole ice core will support a wide range of ice core science projects, which will contribute to the societal need for a basic understanding of climate and the capability to predict climate and ice sheet stability on long time scales. Second, the project will help train the next generation of ice core scientists by providing the opportunity for hands-on field and core processing experience for graduate students and postdoctoral researchers. A postdoctoral researcher at the University of Washington will be directly supported by this project, and many other young scientists will interact with the project through individual science proposals. Third, the project will result in the development of a new intermediate drill which will become an important resource to US ice core science community. This drill will have a light logistical footprint which will enable a wide range of ice core projects to be carried out that are not currently feasible. Finally, although this project does not request funds for outreach activities, the project will run workshops that will encourage and enable proposals for coordinated outreach activities involving the South Pole ice core science team.

EXPROBE-WAIS: Exposed Rock Beneath the West Antarctic Ice Sheet, A Test for Interglacial Ice Sheet Collapse

1341728

2019-10-08

Stone, John

Cosmogenic nuclide data, Harter Nunatak	ICE-D
Pirrit Hills subglacial bedrock core RB-2, cosmogenic Be-10, Al-26 data	USAP-DC
Cosmogenic nuclide data, Mt Goodwin	ICE-D
Cosmogenic nuclide data, Mt Turcotte	ICE-D
Cosmogenic nuclide data, Mt Tidd	ICE-D
Cosmogenic nuclide data, John Nunatak	ICE-D
Cosmogenic nuclide data, Mt Axtell	ICE-D

Stone/1341728 This award supports a project to determine if the West Antarctic Ice Sheet (WAIS) has thinned and collapsed in the past and if so, when did this occur. This topic is of interest to geologists who have long been studying the history and behavior of ice sheets (including the WAIS) in order to determine what climatic conditions allow an ice sheet to survive and what conditions have caused them to collapse in the past. The bulk of this research has focused on the last ice age, when climate conditions were far colder than the present; this project will focus on the response of ice sheets to warmer climates in the past. A new and potentially transformative approach that uses the analysis of atoms transformed by cosmic-rays in bedrock beneath the WAIS will allow a definitive test for ice free conditions in the past. This is because the cosmic rays capable of producing the necessary reactions can penetrate only a few meters through glacier ice. Therefore, if they are detected in samples from hundreds of meters below the current ice sheet surface this would provide definitive proof of mostly ice-free conditions in the past. The concentrations of different cosmic ray products in cores from different depths will help answer the question of how frequently bedrock has been exposed, how much the ice sheet has thinned, and which time periods in the past produced climatic conditions capable of making the ice sheet unstable. Short bedrock cores beneath the ice sheet near the Pirrit Hills in West Antarctica will be collected using a new agile sub-ice geological drill (capable of drilling up to 200 meters beneath the ice surface) that is being developed by the Ice Drilling Program Office (IDPO) to support this and other projects. Favorable drilling sites have already been identified based on prior reconnaissance mapping, sample analysis and radar surveys of the ice-sheet bed. The cores collected in this study will be analyzed for cosmic-ray-produced isotopes of different elements with a range of half-lives from 5700 yr (C-14) to 1.4 Myr (Be-10), as well as stable Ne-21. The presence or absence of these isotopes will provide a definitive test of whether bedrock surfaces were ice-free in the past and due to their different half-lives, ratios of the isotopes will place constraints on the age, frequency and duration of past exposure episodes. Results from bedrock surfaces at different depths will indicate the degree of past ice-sheet thinning. The aim is to tie evidence of deglaciation in the past to specific periods of warmer climate and thus to gauge the ice sheet's response to known climate conditions. This project addresses the broad question of ice-sheet sensitivity to climate warming, which previously has been largely determined indirectly from sea-level records. In contrast, this project will provide direct measurements that provide evidence of ice-sheet thinning in West Antarctica. Results from this work will help to identify the climatic factors and thresholds capable of endangering the WAIS in future. The project will make a significant contribution to the ongoing study of climate change, ice-sheet melting and associated sea-level rise. This project has field work in Antarctica.

Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment

1443248
1443346

2019-09-05

Hall, Brenda; Stone, John

Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast	USAP-DC
Ice-D Antarctic Cosmogenic Nuclide database - site MAASON	ICE-D
Ice-D Antarctic Cosmogenic Nuclide database - site DUNCAN	ICE-D
Liv and Amundsen Glacier Radiocarbon Data	USAP-DC

The response of the Antarctic Ice Sheet to future climatic changes is recognized as the greatest uncertainty in projections of future sea level. An understanding of past ice fluctuations affords insight into ice-sheet response to climate and sea-level change and thus is critical for improving sea-level predictions. This project will examine deglaciation of the southern Ross Sea over the past few thousand years to document oscillations in Antarctic ice volume during a period of relatively stable climate and sea level. We will help quantify changes in ice volume, improve understanding of the ice dynamics responsible, and examine the implications for future sea-level change. The project will train future scientists through participation of graduate students, as well as undergraduates who will develop research projects in our laboratories. Previous research indicates rapid Ross Sea deglaciation as far south as Beardmore Glacier early in the Holocene epoch (which began approximately 11,700 years before present), followed by more gradual recession. However, deglaciation in the later half of the Holocene remains poorly constrained, with no chronological control on grounding-line migration between Beardmore and Scott Glaciers. Thus, we do not know if mid-Holocene recession drove the grounding line rapidly back to its present position at Scott Glacier, or if the ice sheet withdrew gradually in the absence of significant climate forcing or eustatic sea level change. The latter possibility raises concerns for future stability of the Ross Sea grounding line. To address this question, we will map and date glacial deposits on coastal mountains that constrain the thinning history of Liv and Amundsen Glaciers. By extending our chronology down to the level of floating ice at the mouths of these glaciers, we will date their thinning history from glacial maximum to present, as well as migration of the Ross Sea grounding line southwards along the Transantarctic Mountains. High-resolution dating will come from Beryllium-10 surface-exposure ages of erratics collected along elevation transects, as well as Carbon-14 dates of algae within shorelines from former ice-dammed ponds. Sites have been chosen specifically to allow close comparison of these two dating methods, which will afford constraints on Antarctic Beryllium-10 production rates.

Spring Blooms of Sea Ice Algae Along the Western Antarctic Peninsula: Effects of Warming and Freshening on Cell Physiology and Biogeochemical Cycles.

1744645

2019-07-23

Young, Jodi; Deming, Jody

Sea-ice diatom compatible solute shifts	Metabolomics workbench
Dataset: Particulate Organic Carbon and Particulate Nitrogen	BCO-DMO
Dataset: Photosynthetic Pigments	BCO-DMO
Dataset: Physical Profiles of Temperature, Salinity, and Brine Volume	BCO-DMO

Rapid changes in the extent and thickness of sea ice during the austral spring subject microorganisms within or attached to the ice to large fluctuations in temperature, salinity, light and nutrients. This project aims to identify cellular responses in sea-ice algae to increasing temperature and decreasing salinity during the spring melt along the western Antarctic Peninsula and to determine how associated changes at the cellular level can potentially affect dynamic, biologically driven processes. Understanding how sea-ice algae cope with, and are adapted to, their environment will not only help predict how polar ecosystems may change as the extent and thickness of sea ice change, but will also provide a better understanding of the widespread success of photosynthetic life on Earth. The scientific context and resulting advances from the research will be communicated to the general public through outreach activities that includes work with Science Communication Fellows and the popular Polar Science Weekend at the Pacific Science Center in Seattle, Washington. The project will provide student training to college students as well as provide for educational experiences for K-12 school children. There is currently a poor understanding of feedback relationships that exist between the rapidly changing environment in the western Antarctic Peninsula region and sea-ice algal production. The large shifts in temperature and salinity that algae experience during the spring melt affect critical cellular processes, including rates of enzyme-catalyzed reactions involved in photosynthesis and respiration, and the production of stress-protective compounds. These changes in cellular processes are poorly constrained but can be large and may have impacts on local ecosystem productivity and biogeochemical cycles. In particular, this study will focus on the thermal sensitivity of enzymes and the cycling of compatible solutes and exopolymers used for halo- and cryo-protection, and how they influence primary production and the biogeochemical cycling of carbon and nitrogen. Approaches will include field sampling during spring melt, incubation experiments of natural sea-ice communities under variable temperature and salinity conditions, and controlled manipulation of sea-ice algal species in laboratory culture. Employment of a range of techniques, from fast repetition rate fluorometry and gross and net photosynthetic measurements to metabolomics and enzyme kinetics, will tease apart the mechanistic effects of temperature and salinity on cell metabolism and primary production with the goal of quantifying how these changes will impact biogeochemical processes along the western Antarctic Peninsula. 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.

Collaborative Research: Fjord Ecosystem Structure and Function on the West Antarctic Peninsula - Hotspots of Productivity and Biodiversity? (FjordEco)

1443680
1443733
1443705

2019-02-13

Winsor, Peter; Truffer, Martin; Smith, Craig; Powell, Brian; Merrifield, Mark; Vernet, Maria; Kohut, Josh

Expedition data of LMG1702	R2R
Andvord Bay Glacier Timelapse	USAP-DC
Expedition Data	R2R
Sediment macrofaunal abundance and family richness from inner Andvord Bay to the open continental shelf	USAP-DC
Andvord Bay sediment core data collected during the FjordEco project (LMG1510 and NBP1603)	USAP-DC
FjordEco Phytoplankton Ecology Dataset in Andvord Bay	USAP-DC
Fjord-Eco Sediment OrgC OrgN Data - Craig Smith	USAP-DC
NBP1603 Expedition data	R2R
LMG1510 Expedition data	R2R
Expedition Data	R2R

Marine communities along the western Antarctic Peninsula are highly productive ecosystems which support a diverse assemblage of charismatic animals such as penguins, seals, and whales as well as commercial fisheries such as that on Antarctic krill. Fjords (long, narrow, deep inlets of the sea between high cliffs) along the central coast of the Peninsula appear to be intense, potentially climate sensitive, hotspots of biological production and biodiversity, yet the structure and dynamics of these fjord ecosystems are very poorly understood. Because of this intense biological activity and the charismatic fauna it supports, these fjords are also major destinations for a large Antarctic tourism industry. This project is an integrated field and modeling program to evaluate physical oceanographic processes, glacial inputs, water column community dynamics, and seafloor bottom community structure and function in these important yet little understood fjord systems. These Antarctic fjords have characteristics that are substantially different from well-studied Arctic fjords, likely yielding much different responses to climate warming. This project will provide major new insights into the dynamics and climate sensitivity of Antarctic fjord ecosystems, highlighting contrasts with Arctic sub-polar fjords, and potentially transforming our understanding of the ecological role of fjords in the rapidly warming west Antarctic coastal marine landscape. The project will also further the NSF goal of training new generations of scientists, providing scientific training for undergraduate, graduate, and postdoctoral students. This includes the unique educational opportunity for undergraduates to participate in research cruises in Antarctica and the development of a novel summer graduate course on fjord ecosystems. Internet based outreach activities will be enhanced and extended by the participation of a professional photographer who will produce magazine articles, websites, radio broadcasts, and other forms of public outreach on the fascinating Antarctic ecosystem. This project will involve a 15-month field program to test mechanistic hypotheses concerning oceanographic and glaciological forcing, and phytoplankton and benthic community response in the Antarctic fjords. Those efforts will be followed by a coupled physical/biological modeling effort to evaluate the drivers of biogeochemical cycles in the fjords and to explore their potential sensitivity to enhanced meltwater and sediment inputs. Fieldwork over two oceanographic cruises will utilize moorings, weather stations, and glacial, sea-ice and seafloor time-lapse cameras to obtain an integrated view of fjord ecosystem processes. The field team will also make multiple shipboard measurements and will use towed and autonomous underwater vehicles to intensively evaluate fjord ecosystem structure and function during spring/summer and autumn seasons. These integrated field and modeling studies are expected to elucidate fundamental properties of water column and sea bottom ecosystem structure and function in the fjords, and to identify key physical-chemical-glaciological forcing in these rapidly warming ecosystems.

Collaborative Research: Mantle Structure and Dynamics of the Ross Sea from a Passive Seismic Deployment on the Ross Ice Shelf

1141916

2018-10-22

Aster, Richard

Dynamic Response of the Ross Ice Shelf to Ocean Waves and Structure and Dynamics of the Ross Sea

IRIS

Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea

1341585

2018-05-25

Sorlien, Christopher; Luyendyk, Bruce P.

Ross Sea unconformities digital grids in depth and two-way time

USAP-DC

Intellectual Merit: This project will produce a new compilation of Ross Sea seismic stratigraphy, including new interpretations, that can be used to provide boundary conditions on the tectonic and glacial evolution of West Antarctica and the Ross Sea. The principal goals include compilation of, and interpretation of, all available existing seismic reflection data for the Western Ross Sea, coupled with geophysical modeling to produce paleo-bathymetric reconstructions for the entire 800 km-wide Ross Sea. Specific tasks will include: extending existing work on mapping travel time to reflectors, identifying relations in the seismic data that indicate subsidence through sea level, constructing velocity models for converting travel time to thickness, and using the velocity models to estimate density and porosity of sediments for backstripping analysis. Modeling/backstripping efforts will be used to constrain past bathymetry. Digital interpretations and stratigraphic grids will be provided as supplements to publications. In that way the results of this study can be used in thermal subsidence modeling and restoration of eroded rock to other parts of Ross Embayment and Marie Byrd Land by others. Digital products may be provided in advance of publication to modelers in a way that will not hurt publication chances. Broader impacts: The results of this work will be important for paleo-geographic reconstructions of Antarctica and will therefore be of use to a broad range of researchers, particularly those working in the Ross Sea region. The digital products can be used to test models for the past fluctuations of West Antarctic ice sheets, and in planning for future sediment drilling projects. Two undergraduates to be chosen from applicants will be involved in summer internships held at the University of Rhode Island. Outreach will also include a new website and one or more Wikipedia entries related to Ross Sea sub-sea floor characteristics. The project includes an international collaboration with Dr. Chiara Sauli and others at Instituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS) in Italy.

Paleomagnetism and Magnetostratigraphy of the James Ross Basin, Antarctica

1341729

2018-04-27

Kirschvink, Joseph; Christensen, John

Expedition data of NBP1601	R2R
2016 Paleomagnetic samples from the James Ross Basin, Antarctica	USAP-DC

Non-Technical Summary: About 80 million years ago, the tip of the Antarctic Peninsula in the vicinity of what is now James Ross Island experienced an episode of rapid subsidence, creating a broad depositional basin that collected sediments eroding from the high mountains to the West. This depression accumulated a thick sequence of fossil-rich, organic-rich sediments of the sort that are known to preserve hydrocarbons, and for which Argentina, Chile, and the United Kingdom have overlapping territorial claims. The rocks preserve one of the highest resolution records of the biological and climatic events that led to the eventual death of the dinosaurs at the Cretaceous-Tertiary boundary (about 66 million years ago). A previous collaboration between scientists from the Instituto Antártico Argentino (IAA) and NSF-supported teams from Caltech and the University of Washington were able to show that this mass extinction event started nearly 50,000 years before the sudden impact of an asteroid. The asteroid obviously hit the biosphere hard, but something else knocked it off balance well before the asteroid hit. A critical component of the previous work was the use of reversals in the polarity of the Earth?s magnetic field as a dating tool ? magnetostratigraphy. This allowed the teams to correlate the pattern of magnetic reversals from Antarctica with elsewhere on the planet. This includes data from a major volcanic eruption (a flood basalt province) that covered much of India 65 million years ago. The magnetic patterns indicate that the Antarctic extinction started with the first pulse of this massive eruption, which was also coincident with a rapid spike in polar temperature. The Argentinian and US collaborative teams will extend this magnetic polarity record back another ~ 20 million years in time, and expand it laterally to provide magnetic reversal time lines across the depositional basin. They hope to recover the end of the Cretaceous Long Normal interval, which is one of the most distinctive events in the history of Earth?s magnetic field. The new data should refine depositional models of the basin, allow better estimates of potential hydrocarbon reserves, and allow biotic events in the Southern hemisphere to be compared more precisely with those elsewhere on Earth. Other potential benefits of this work include exposing several US students and postdoctoral fellows to field based research in Antarctica, expanding the international aspects of this collaborative work via joint IAA/US field deployments, and follow-up laboratory investigations and personnel exchange of the Junior scientists. Technical Description of Project The proposed research will extend the stratigraphic record in the late Cretaceous and early Tertiary sediments (~ 83 to 65 Ma before present) of the James Ross Basin, Antarctica, using paleo-magnetic methods. Recent efforts provided new methods to analyze these rocks, yielding their primary magnetization, and producing both magnetic polarity patterns and paleomagnetic pole positions. This provided the first reliable age constraints for the younger sediments on Seymour Island, and quantified the sedimentation rate in this part of the basin. The new data will allow resolution of the stable, remnant magnetization of the sediments from the high deposition rate James Ross basin (Tobin et al., 2012), yielding precise chronology/stratigraphy. This approach will be extended to the re-maining portions of this sedimentary basin, and will allow quantitative estimates for tectonic and sedimentary processes between Cretaceous and Early Tertiary time. The proposed field work will refine the position of several geomagnetic reversals that occurred be-tween the end of the Cretaceous long normal period (Chron 34N, ~ 83 Ma), and the lower portion of Chron 31R (~ 71 Ma). Brandy Bay provides the best locality for calibrating the stratigraphic position of the top of the Cretaceous Long Normal Chron, C34N. Although the top of the Cretaceous long normal Chron is one of the most important correlation horizons in the entire geological timescale, it is not properly correlated to the southern hemisphere biostratigraphy. Locating this event, as well as the other reversals, will be a major addition to understanding of the geological history of the Antarctic Peninsula. These data will also help refine tectonic models for the evolution of the Southern continents, which will be of use across the board for workers in Cretaceous stratigraphy (including those involved in oil exploration). This research is a collaborative effort with Dr. Edward Olivero of the Centro Austral de Investigaciones Cientificas (CADIC/CONICET) and Prof. Augusto Rapalini of the University of Buenos Aires. The collaboration will include collection of samples on their future field excursions to important targets on and around James Ross Island, supported by the Argentinian Antarctic Program (IAA). Argentinian scientists and students will also be involved in the US Antarctic program deployments, proposed here for the R/V Laurence Gould, and will continue the pattern of joint international publication of the results.

Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM)

1425989

2017-12-29

Sarmiento, Jorge; Rynearson, Tatiana

Biogeochemical profiling float data from the Southern Ocean Carbon and Climate Observation and Modeling (SOCCOM) program.UCSD Research Data Collections DOI:10.6075/J09021PC	PI website
Expedition Data	R2R
Model output NOAA GFDL CM2_6 Cant Hant storage	USAP-DC

Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) project seeks to drive a transformative shift in our understanding of the crucial role of the Southern Ocean in taking up anthropogenic carbon and heat, and resupplying nutrients from the abyss to the surface. An observational program will generate vast amounts of new biogeochemical data that will provide a greatly improved view of the dynamics and ecosystem responses of the Southern Ocean. A modeling component will apply these observations to enhancing understanding of the current ocean, reducing uncertainty in projections of future carbon and nutrient cycles and climate. Because it serves as the primary gateway through which the intermediate, deep, and bottom waters of the ocean interact with the surface layers and thus the atmosphere, the Southern Ocean has a profound influence on the oceanic uptake of anthropogenic carbon and heat as well as nutrient resupply from the abyss to the surface. Yet it is the least observed and understood region of the world ocean. The oceanographic community is on the cusp of two major advances that have the potential to transform understanding of the Southern Ocean. The first is the development of new biogeochemical sensors mounted on autonomous profiling floats that allow sampling of ocean biogeochemistry and acidification in 3-dimensional space with a temporal resolution of five to ten days. The SOCCOM float program proposed will increase the average number of biogeochemical profiles measured per month in the Southern Ocean by ~10-30x. The second is that the climate modeling community now has the computational resources and physical understanding to develop fully coupled climate models that can represent crucial mesoscale processes in the Southern Ocean, as well as corresponding models that assimilate observations to produce a state estimate. Together with the observations, this new generation of models provides the tools to vastly improve understanding of Southern Ocean processes and the ability to quantitatively assess uptake of anthropogenic carbon and heat, as well as nutrient resupply, both today and into the future. In order to take advantage of the above technological and modeling breakthroughs, SOCCOM will implement the following research programs: * Theme 1: Observations. Scripps Institution of Oceanography will lead a field program to expand the number of Southern Ocean autonomous profiling floats and equip them with sensors to measure pH, nitrate, and oxygen. The University of Washington and Monterey Bay Aquarium Research Institute will design, build, and oversee deployment of the floats. Scripps will also develop a mesoscale eddying Southern Ocean state estimate that assimilates physical and biogeochemical data into the MIT ocean general circulation model. * Theme 2: Modeling. University of Arizona and Princeton University, together with NOAA's Geophysical Fluid Dynamics Laboratory (GFDL), will use SOCCOM observations to develop data/model assessment metrics and next-generation model analysis and evaluation, with the goal of improving process level understanding and reducing the uncertainty in projections of our future climate. Led by Climate Central, an independent, non-profit journalism and research organization that promotes understanding of climate science, SOCCOM will collaborate with educators and media professionals to inform policymakers and the public about the challenges of climate change and its impacts on marine life in the context of the Southern Ocean. In addition, the integrated team of SOCCOM scientists and educators will: * communicate data and results of the SOCCOM efforts quickly to the public through established data networks, publications, broadcast media, and a public portal; * train a new generation of diverse ocean scientists, including undergraduate students, graduate students, and postdoctoral fellows versed in field techniques, data calibration, modeling, and communication of research to non-scientists; * transfer new sensor technology and related software to autonomous instrument providers and manufacturers to ensure that they become widely useable.

Collaborative Proposal: Decades-long Experiment on Wind-Driven Rock Abrasion in the Ice-Free Valleys, Antarctica

1341712

2017-10-13

Hallet, Bernard; Sletten, Ronald S.

Long-term rock abrasion study in the Dry Valleys

USAP-DC

Paragraph for Public Audiences: 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 1980's and early 1990's 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. Technical Description of Project: 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.

Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores

1341360

2017-06-06

Steig, Eric J.

Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits

USAP-DC

Steig/1341360 This award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.

Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core

1043092
1043167

2016-09-15

White, James; Vaughn, Bruce; Jones, Tyler R.

Seasonal temperatures in West Antarctica during the Holocene	USAP-DC
Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core	USAP-DC
Resampling of Deep Polar Ice Cores using Information Theory	USAP-DC
Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core	USAP-DC
WAIS Divide Ice Core Discrete CH4 (80-3403m)	USAP-DC

Steig/1043092 This award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.

Spectral and Broadband Albedo of Antarctic Sea-ice Types

1141275

2015-01-30

Warren, Stephen; Zatko, Maria

Antarctic field campaign data page

PI website

Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core

1043167
1043092

2014-12-06

Steig, Eric J.

WAIS Divide Ice Core Discrete CH4 (80-3403m)	USAP-DC
17O excess from WAIS Divide, 0 to 25 ka BP	USAP-DC
WAIS Divide WDC06A Oxygen Isotope Record	USAP-DC

This award supports a project to contribute one of the cornerstone analyses, stable isotopes of ice (Delta-D, Delta-O18) to the ongoing West Antarctic Ice Sheet Divide (WAIS) deep ice core. The WAIS Divide drilling project, a multi-institution project to obtain a continuous high resolution ice core record from central West Antarctica, reached a depth of 2560 m in early 2010; it is expected to take one or two more field seasons to reach the ice sheet bed (~3300 m), plus an additional four seasons for borehole logging and other activities including proposed replicate coring. The current proposal requests support to complete analyses on the WAIS Divide core to the base, where the age will be ~100,000 years or more. These analyses will form the basis for the investigation of a number of outstanding questions in climate and glaciology during the last glacial period, focused on the dynamics of the West Antarctic Ice Sheet and the relationship of West Antarctic climate to that of the Northern polar regions, the tropical Pacific, and the rest of the globe, on time scales ranging from years to tens of thousands of years. One new aspect of this work is the growing expertise at the University of Washington in climate modeling with isotope-tracer-enabled general circulation models, which will aid in the interpretation of the data. Another major new aspect is the completion and use of a high-resolution, semi-automated sampling system at the University of Colorado, which will permit the continuous analysis of isotope ratios via laser spectroscopy, at an effective resolution of ~2 cm or less, providing inter-annual time resolution for most of the core. Because continuous flow analyses of stable ice isotopes is a relatively new measurement, we will complement them with parallel measurements, every ~10-20 m, using traditional discrete sampling and analysis by mass spectrometry at the University of Washington. The intellectual merit and the overarching goal of the work are to see Inland WAIS become the reference ice isotope record for West Antarctica. The broader impacts of the work are that the data generated in this project pertain directly to policy-relevant and immediate questions of the stability of the West Antarctic ice sheet, and thus past and future changes in sea level, as well as the nature of climate change in the high southern latitudes. The project will also contribute to the development of modern isotope analysis techniques using laser spectroscopy, with applications well beyond ice cores. The project will involve a graduate student and postdoc who will work with both P.I.s, and spend time at both institutions. Data will be made available rapidly through the Antarctic Glaciological Data Center, for use by other researchers and the public.

Ocean Surfaces on Snowball Earth

0739779
1142963

2013-07-10

Warren, Stephen; Light, Bonnie; Campbell, Adam; Carns, Regina; Dadic, Ruzica; Mullen, Peter; Brandt, Richard; Waddington, Edwin D.

Ice on the Oceans of Snowball Earth Project Data

PI website

The climatic changes of late Precambrian time, 600-800 million years ago, included episodes of extreme glaciation, during which ice may have covered nearly the entire ocean for several million years, according to the Snowball Earth hypothesis. These episodes would hold an important place in Earth?s evolutionary history; they could have encouraged biodiversity by trapping life forms in small isolated ice-free areas, or they could have caused massive extinctions that cleared the path for new life forms to fill empty niches. What caused the Earth to become iced over, and what later caused the ice to melt? Scientific investigation of these questions will result in greater understanding of the climatic changes that the Earth can experience, and will enable better predictions of future climate. This project involves Antarctic field observations as well as laboratory studies and computer modeling. The aim of this project is not to prove or disprove the Snowball Earth hypothesis but rather to quantify processes that are important for simulating snowball events in climate models. The principal goal is to identify the types of ice that would have been present on the frozen ocean, and to determine how much sunlight they would reflect back to space. Reflection of sunlight by bright surfaces of snow and ice is what would maintain the cold climate at low latitudes. The melting of the ocean required buildup of greenhouse gases, but it was probably aided by deposition of desert dust and volcanic ash darkening the snow and ice. With so much ice on the Earth?s surface, even small differences in the amount of light that the ice absorbed or reflected could cause significant changes in climate. The properties of the ice would also determine where, and in what circumstances, photosynthetic life could have survived. Some kinds of ice that are rare on the modern Earth may have been pivotal in allowing the tropical ocean to freeze. The ocean surfaces would have included some ice types that now exist only in Antarctica: bare cold sea ice with precipitated salts, and "blue ice" areas of the Transantarctic Mountains that were exposed by sublimation and have not experienced melting. Field expeditions were mounted to examine these ice types, and the data analysis is underway. A third ice type, sea ice with a salt crust, is being studied in a freezer laboratory. Modeling will show how sunlight would interact with ice containing light-absorbing dust and volcanic ash. Aside from its reflection of sunlight, ice on the Snowball ocean would have been thick enough to flow under its own weight, invading all parts of the ocean. Yet evidence for the survival of photosynthetic life indicates that some regions of liquid water were maintained at the ocean surface. One possible refuge for photosynthetic organisms is a bay at the far end of a nearly enclosed tropical sea, formed by continental rifting and surrounded by desert, such as the modern Red Sea. A model of glacier flow is being developed to determine the dimensions of the channel, connecting the sea to the ocean, necessary to prevent invasion by the flowing ice yet maintain a water supply to replenish evaporation.

IPY: Collaborative Proposal: Constraining the Mass-Balance Deficit of the Amundsen Coast's Glaciers

0631973
0632031

2012-06-20

Joughin, Ian; Medley, Brooke; Das, Sarah

No dataset link provided

Joughin 0631973 This award supports a project to gather data to better understand the mass balance of the West Antarctic Ice Sheet, in the Pine Island and Thwaites region, through the combination of radar altimetry and surface-based ice-core measurements of accumulation. The intellectual merit of the project is that the results of the field work will provide information on decadal-scale average accumulation extending back through the last century and will help constrain a modeling effort to determine how coastal changes propagate inland, to allow better prediction of future change. Comparison of the basin averaged accumulation with ice discharge determined using Interferometric Synthetic Aperture Radar (InSAR) velocity data will provide improved mass-balance estimates. Study of changes in flow speed will produce a record of mass balance over the last three decades. Analysis of the satellite altimeter record in conjunction with annual accumulation estimates also will provide estimates of changes and variability in mass balance. The broader impacts of the work are that it will make a significant contribution to future IPCC estimates of sea level, which are important for projection of the impacts of increased sea level on coastal communities. The research will contribute to the graduate education of students at the Universities of Washington and Kansas and will enrich K-12 education through the direct participation of the PIs in classroom activities. Informal science education includes 4-day glacier flow demonstrations at the Polar Science Weekend held annually at the Pacific Science Center in Seattle. The project also will communicate results through Center for the Remote Sensing of Ice Sheets (CReSIS) outreach effort. All field and remotely-sensed data sets will be archived and distributed by the National Snow and Ice Data Center. This project is relevant to IPY in that the West Antarctic Ice Sheet is losing mass, in large part because of rapid thinning of the Amundsen Coast glaciers so, it will directly address the NSF IPY emphasis on "ice sheet history and dynamics." The project is also international in scope.

Investigation of the Stratigraphy and Time Scale of the WAIS Divide Ice Core Using Electrical Methods

0440819

2012-06-19

Taylor, Kendrick C.

No dataset link provided

Self-consistent Ice Dynamics, Accumulation, Delta-age, and Interpolation of Sparse Age Data using an Inverse Approach

0636997

2012-03-20

Carns, Regina; Hay, Mike; Waddington, Edwin D.

No dataset link provided

Waddington/0636997 This award supports a project to integrate three lines of glaciology research, previously treated independently. First, internal layers in ice sheets, detected by ice-penetrating radar, retain information about past spatial and temporal patterns of ice accumulation. Ice-flow modelers can recover this information, using geophysical inverse methods; however, the ages of the layers must be known, through interpolation where they intersect a well-dated ice core. Second, concentrations of methane and some other atmospheric constituents vary through time as climate changes. However, the atmosphere is always well mixed, and concentrations are similar world-wide at any one time, so gas variations from an undated core can be correlated with those in a well-dated core such as GISP2. Because air in near-surface firn mixes readily with the atmosphere above, the air that is trapped in bubbles deep in the firn is typically hundreds to thousands of years younger than that firn. Gas geochemists must calculate this age difference, called delta-age, with a firn-densification model before the ice enclosing the gas can be dated accurately. To calculate delta-age, they must know the temperature and the snow accumulation rate at the time and place where the snow fell. Third, gases can be correlated between cores only at times when the atmosphere changed, so ice-core dates must be interpolated at depths between the sparse dated points. Simplistic interpolation schemes can create undesirable artifacts in the depth-age profile. The intellectual merit of this project is that it will develop new interpolation methods that calculate layer thinning over time due to ice-flow mechanics. Accurate interpolation also requires a spatial and temporal accumulation history. These three issues are coupled through accumulation patterns and ice-core dates. This project will develop an integrated inversion procedure to solve all three problems simultaneously. The new method will incorporate ice-penetrating radar profile data and ice-core data, and will find self-consistent: spatial/temporal accumulation patterns; delta-age profiles for ice cores; and reliably interpolated depth-age profiles. The project will then: recalculate the depth-age profile at Byrd Station, Antarctica; provide a preliminary depth-age at the West Antarctic Ice Sheet (WAIS) in the initial stages of drilling, using radar layers with estimated ages traced from Byrd Station; and generate a self-consistent depth-age relationship for Taylor Dome, Antarctica over the past 20ka, where low accumulation has created uncertainty in dating, accumulation, and controversy over delta-age estimates. The broader impacts of the project are that it will support the PhD research of a female graduate student, and her continued outreach work with Making Connections, a non-profit program through the University of Washington Women's Center, which matches professional women mentors with minority high-school women interested in mathematics and science, disciplines where they are traditionally under-represented. The graduate student will also work with Girls on Ice, a ten-day glacier field program, taught by women scientist instructors, emphasizing scientific observation through immersion, leadership skills and safety awareness.

Collaborative Research:Grounding-line Retreat in the Southern Ross Sea - Constraints from Scott Glacier

0636818

2011-08-05

Stone, John; Conway, Howard

No dataset link provided

Hall/0636687 This award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, surface velocity and surface mass balance will be measured to constrain an ice-flow model of the glacier. This model will be used to help interpret the dated geologic sequences. The intellectual merit of the project relates to gaining a better understanding of the West Antarctic Ice Sheet and how changing activity of fast-flowing outlet glaciers and ice streams exerts strong control on the mass balance of the ice sheet. Previous work suggests that grounding-line retreat in the Ross Sea continued into the late Holocene and left open the possibility of ongoing deglaciation as part of a long-term trend. Results from Reedy Glacier, an outlet glacier just behind the grounding line, suggest that retreat may have slowed substantially over the past 2000 years and perhaps even stopped. By coupling the work on Scott Glacier with recent data from Reedy Glacier, the grounding-line position will be bracketed and it should be possible to establish whether the retreat has truly ended or if it is ongoing. The broader impacts of the work relate to the societal relevance of an improved understanding of the West Antarctic ice sheet to establish how it will respond to current and possible future environmental changes. The work addresses this key goal of the West Antarctic Ice Sheet Initiative, as well as the International Polar Year focus on ice sheet history and dynamics. The work will develop future scientists through the education and training of one undergraduate and two Ph.D. students, interaction with K-12 students through classroom visits, web-based 'expedition' journals, letters from the field, and discussions with teachers. Results from this project will be posted with previous exposure dating results from Antarctica, on the University of Washington Cosmogenic Nuclide Lab website, which also provides information about chemical procedures and calculation methods to other scientists working with cosmogenic nuclides.

Center for Remote Sensing of Ice Sheets (CReSIS)

0424589

2011-06-01

Braaten, David; Joughin, Ian; Steig, Eric J.; Das, Sarah; Paden, John; Gogineni, Prasad

Ku-band Radar Echograms	USAP-DC
Radar Depth Sounder Echograms and Ice Thickness	USAP-DC
Airborne radar profiles of the Whillans, Bindschadler, and Kamb Ice Streams	USAP-DC
Snow Radar Echograms	USAP-DC
Ice-penetrating radar internal stratigraphy over Dome C and the wider East Antarctic Plateau	USAP-DC
Archive of data	Project website

This award is for the continuation of the Center for Remote Sensing of Ice Sheets (CReSIS), an NSF Science and Technology Center (STC) established in June 2005 to study present and probable future contributions of the Greenland and Antarctic ice sheets to sea-level rise. The Center?s vision is to understand and predict the role of polar ice sheets in sea level change. In particular, the Center?s mission is to develop technologies, to conduct field investigations, to compile data to understand why many outlet glaciers and ice streams are changing rapidly, and to develop models that explain and predict ice sheet response to climate change. The Center?s mission is also to educate and train a diverse population of graduate and undergraduate students in Center-related disciplines and to encourage K-12 students to pursue careers in science, technology, engineering and mathematics (STEM-fields). The long-term goals are to perform a four-dimensional characterization (space and time) of rapidly changing ice-sheet regions, develop diagnostic and predictive ice-sheet models, and contribute to future assessments of sea level change in a warming climate. In the first five years, significant progress was made in developing, testing and optimizing innovative sensors and platforms and completing a major aircraft campaign, which included sounding the channel under Jakobshavn Isbræ. In the second five years, research will focus on the interpretation of integrated data from a suite of sensors to understand the physical processes causing changes and the subsequent development and validation of models. Information about CReSIS can be found at http://www.cresis.ku.edu. The intellectual merits of the STC are the multidisciplinary research it enables its faculty, staff and students to pursue, as well as the broad education and training opportunities it provides to students at all levels. During the first phase, the Center provided scientists and engineers with a collaborative research environment and the opportunity to interact, enabling the development of high-sensitivity radars integrated with several airborne platforms and innovative seismic instruments. Also, the Center successfully collected data on ice thickness and bed conditions, key variables in the study of ice dynamics and the development of models, for three major fast-flowing glaciers in Greenland. During the second phase, the Center will collect additional data over targeted sites in areas undergoing rapid changes; process, analyze and interpret collected data; and develop advanced process-oriented and ice sheet models to predict future behavior. The Center will continue to provide a rich environment for multidisciplinary education and mentoring for undergraduate students, graduate students, and postdoctoral fellows, as well as for conducting K-12 education and public outreach. The broader impacts of the Center stem from addressing a global environmental problem with critical societal implications, providing a forum for citizens and policymakers to become informed about climate change issues, training the next generation of scientists and engineers to serve the nation, encouraging underrepresented students to pursue careers in STEM-related fields, and transferring new technologies to industry. Students involved in the Center find an intellectually stimulating atmosphere where collaboration between disciplines is the norm and exposure to a wide variety of methodologies and scientific issues enriches their educational experience. The next generation of researchers should reflect the diversity of our society; the Center will therefore continue its work with ECSU to conduct outreach and educational programs that attract minority students to careers in science and technology. The Center has also established a new partnership with ADMI that supports faculty and student exchanges at the national level and provides expanded opportunities for students and faculty to be involved in Center-related research and education activities. These, and other collaborations, will provide broader opportunities to encourage underrepresented students to pursue STEM careers. As lead institution, The University of Kansas (KU) provides overall direction and management, as well as expertise in radar and remote sensing, Uninhabited Aerial Vehicles (UAVs), and modeling and interpretation of data. Five partner institutions and a DOE laboratory play critical roles in the STC. The Pennsylvania State University (PSU) continues to participate in technology development for seismic measurements, field activities, and modeling. The Center of Excellence in Remote Sensing, Education and Research (CERSER) at Elizabeth City State University (ECSU) contributes its expertise to analyzing satellite data and generating high-level data products. ECSU also brings to the Center their extensive experience in mentoring and educating traditionally under-represented students. ADMI, the Association of Computer and Information Science/Engineering Departments at Minority Institutions, expands the program?s reach to underrepresented groups at the national level. Indiana University (IU) provides world-class expertise in CI and high-performance computing to address challenges in data management, processing, distribution and archival, as well as high-performance modeling requirements. The University of Washington (UW) provides expertise in satellite observations of ice sheets and process-oriented interpretation and model development. Los Alamos National Laboratory (LANL) contributes in the area of ice sheet modeling. All partner institutions are actively involved in the analysis and interpretation of observational and numerical data sets.

Glaciological Characteristics of the Ross/Amundsen Sea Ice-flow Divide Deduced by a New Analysis of Ice-penetrating Radar Data

0338151

2010-05-11

Raymond, Charles; Matsuoka, Kenichi; Luyendyk, Bruce P.; Wilson, Douglas S.

Englacial Layers and Attenuation Rates across the Ross and Amundsen Sea Ice-Flow Divide (WAIS Divide), West Antarctica	USAP-DC
Surface Elevation and Ice Thickness, Western Marie Byrd Land, Antarctica	USAP-DC

Collaborative Research: The Maud Rise Nonlinear Equation of State Study (MaudNESS)

0337159

2010-05-04

McPhee, Miles G.

Processed ADCP Sonar and CTD Data from the Maud Rise acquired during the Nathaniel B. Palmer expedition NBP0506	USAP-DC
Expedition Data	R2R

Acquisition and Operation of Broadband Seismograph Equipment at Chilean Bases in the Antarctic Peninsula Region

9814622

2010-05-04

Wiens, Douglas; Visbeck, Martin

Expedition Data	R2R
Expedition Data	R2R
Expedition data of LMG0003A	R2R

This award, provided jointly by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research to transform three temporary seismometers in the Antarctic Peninsula into semi-permanent stations and to continue basic research using these data. During 1997 and 1998, a network of 11 broadband seismographs in the Antarctic Peninsula region and southernmost Chilean Patagonia were installed and maintained. Data return from this project has been excellent and interesting initial results have been produced. The continued operation of these instruments over a longer time period would be highly beneficial because the number of larger magnitude regional earthquakes is small and so a longer time is needed to acquire data. However, instruments from this project are borrowed from the IRIS-PASSCAL instrument pool and must be returned to PASSCAL in April, 1999. This award provides funds to convert three stations at permanent Chilean bases in the Antarctic to permanent stations, and to continue the seismological investigation of the region for a period of four years. As part of this project, a fourth station, in Chilean Patagonia, will continue to be operated using Washington University equipment. The funding of this project will enable continued collaboration between Washington University and the Universidad de Chile in the operation of these stations, and the data will be forwarded to the IRIS data center as well as to other international seismological collaborators. Mutual data exchanges with other national groups with Antarctic seismology research programs will provide access to broadband data from a variety of other proprietary broadband stations in the region. The data will be used to study the seismicity and upper mantle velocity structure of several complicated tectonic regions in the area, including the South Shetland subduction zone, the Bransfield backarc rift, and diffuse plate boundaries in Patagonia, Drake Passage, and along the South Scotia Ridge. In particular, the operation of these stations over a longer time period will allow a better understanding of the seismicity of the South Shetland Trench, an unusual subduction zone showing very slow subduction of young lithosphere. These seismometers will also be used to record airgun shots during a geophysical cruise in the Bransfield Strait that is being planned by the University of Texas for April, 2000. These data will provide important constraints on the crustal structure beneath the stations, and the improved structural models will enable implementation of more precise earthquake location procedures in support of a seismological understanding of the region.

Histories of accumulation, thickness and WAIS Divide location from radar layers using a new inverse approach

0440666

2010-03-04

Koutnik, Michelle; Waddington, Edwin D.

Histories of Accumulation, Thickness, and WAIS Divide Location, Antarctica

USAP-DC

Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica

0440954
0440919
0551163

2009-10-12

Miller, Molly; Sidor, Christian; Isbell, John

Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617	Burke Museum
Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica	USAP-DC

This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate. In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.

Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)

9911617
9319379

2009-02-06

Carter, Sasha P.; Holt, John W.; Blankenship, Donald D.; Morse, David L.; Dalziel, Ian W.

SOAR-Lake Vostok Survey airborne radar data	USAP-DC
Antarctic Subglacial Lake Classification Inventory	USAP-DC
SOAR-Lake Vostok Survey bed elevation data	USAP-DC
SOAR-Lake Vostok Survey surface elevation data	USAP-DC
SOAR-Lake Vostok Survey ice thickness data	USAP-DC
SOAR-Lake Vostok survey magnetic anomaly data	USAP-DC
SOAR-Lake Vostok Survey Gravity data	USAP-DC
Antarctic Aerogeophysics Data	USAP-DC
RBG - Robb Glacier Survey	USAP-DC

9911617 Blankenship This award, provided jointly by the Antarctic Geology and Geophysics Program, the Antarctic Glaciology Program, and the Polar Research Support Section of the Office of Polar Programs, provides funds for continuation of the Support Office for Aerogeophysical Research (SOAR). From July 1994 to July 2000, SOAR served as a facility to accomplish aerogeophysical research in Antarctica under an agreement between the University of Texas at Austin and the National Science Foundation's Office of Polar Programs (NSF/OPP). SOAR operated and maintained an aerogeophysical instrument package that consists of an ice-penetrating radar sounder, a laser altimeter, a gravimeter and a magnetometer that are tightly integrated with each other as well as with the aircraft's avionics and power packages. An array of aircraft and ground-based GPS receivers supported kinematic differential positioning using carrier-phase observations. SOAR activities included: developing aerogeophysical research projects with NSF/OPP investigators; upgrading of the aerogeophysical instrumentation package to accommodate new science projects and advances in technology; fielding this instrument package to accomplish SOAR-developed projects; and management, reduction, and analysis of the acquired aerogeophysical data. In pursuit of 9 NSF-OPP funded aerogeophysical research projects (involving 14 investigators from 9 institutions), SOAR carried out six field campaigns over a six-year period and accomplished approximately 200,000 line kilometers of aerogeophysical surveying over both East and West Antarctica in 377 flights. This award supports SOAR to undertake a one year and 8 month program of aerogeophysical activities that are consistent with continuing U.S. support for geophysical research in Antarctica. - SOAR will conduct an aerogeophysical campaign during the 200/01 austral summer to accomplish surveys for two SOAR-developed projects: "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Studies" (Co-PI's Bell and Studinger, LDEO); and "Collaborative Research: Seismic Investigation of the Deep Continental Structure Across the East-West Antarctic Boundary" (Co-PI's Weins, Washington U. and Anandakrishnan, U. Alabama). After configuration and testing of the survey aircraft in McMurdo, SOAR will conduct survey flights from an NSF-supported base adjacent to the Russian Station above Lake Vostok and briefly occupy one or two remote bases on the East Antarctic ice sheet. - SOAR will reduce these aerogeophysical data and produce profiles and maps of surface elevation, bed elevation, gravity and magnetic field intensity. These results will be provided to the respective project investigators within nine months of conclusion of field activities. We will also submit a technical manuscript that describes these results to a refereed scientific journal and distribute these results to appropriate national geophysical data centers within approximately 24 months of completion of field activities. - SOAR will standardize all previously reduced SOAR data products and transfer them to the appropriate national geophysical data centers by the end of this grant. - SOAR will convene a workshop to establish a community consensus for future U.S. Antarctic aerogeophysical research. This workshop will be co-convened by Ian Dalziel and Richard Alley and will take place during the spring of 2001. - SOAR will upgrade the existing SOAR in-field quality control procedures to serve as a web-based interface for efficient browsing of many low-level SOAR data streams. - SOAR will repair and/or refurbish equipment that was used during the 2000/01 field campaign. Support for SOAR is essential for accomplishing major geophysical investigations in Antarctica. Following data interpretation by the science teams, these data will provide valuable insights to the structure and evolution of the Antarctic continent.

Developing Dry Extraction of Ice Core Gases and Application to Millennial-Scale Variability in Atmospheric CO2

0337891

2007-11-05

Ahn, Jinho; Brook, Edward J.

Atmospheric CO2 and Climate: Taylor Dome Ice Core, Antarctica	USAP-DC
Atmospheric CO2 and Climate: Byrd Ice Core, Antarctica	USAP-DC

This award supports the development of a new laboratory capability in the U.S. to measure CO2 in ice cores and investigate millennial-scale changes in CO2 during the last glacial period using samples from the Byrd and Siple Dome ice cores. Both cores have precise relative chronologies based on correlation of methane and the isotopic composition of atmospheric oxygen with counterpart records from Greenland ice cores. The proposed work will therefore allow comparison of the timing of CO2 change, Antarctic temperature change, and Greenland temperature change on common time scales. Such comparisons are vital for evaluating models that explain changes in atmospheric CO2. The techniques being developed will also be available for future projects, specifically the proposed Inland WAIS ice core, for which a highly detailed CO2 record is a major objective, and studies greenhouse and other atmospheric gases and their isotopic composition for which dry extraction is necessary (stable isotopes in CO2, for example). There are many broad impacts of the proposed work. Ice core greenhouse gas records are central contributions of paleoclimatology to research and policy-making concerning global change. The proposed work will enhance those contributions by improving our understanding of the natural cycling of the most important greenhouse gas. It will contribute to the training of a postdoctoral researcher, who will be an integral part of an established research group and benefit from the diverse paleoclimate and geochemistry community at OSU. The PI teaches major and non-major undergraduate and graduate courses on climate and global change. The proposed work will enrich those courses and the courses will provide an opportunity for the postdoctoral researcher to participate in teaching by giving guest lectures. The PI also participates in a summer climate workshop for high school teachers at Washington State University and the proposed work will enrich that contribution. The extraction device that is built and the expertise gained in using it will be resources for the ice core community and available for future projects. Data will be made available through established national data center and the equipment designs will also be made available to other researchers.

Ice Dynamics, the Flow Law, and Vertical Strain at Siple Dome

9615502

2007-02-22

Harrison, William; Morack, James; Pettit, Erin; Zumberge, Mark; Elsberg, Daniel; Waddington, Edwin D.

Vertical Strain at Siple Dome, Antarctica, 1999-2002

USAP-DC

Collaborative Research: Fabric and Texture Characteristics of Micro-Physical Processes in Ice

0135989

2005-03-02

Wilen, Larry

Ice Fabric Characteristics: Siple Dome, A Core

USAP-DC

0135989 Wilen This is a collaborative proposal by Principal Investigators at the University of Washington and Ohio University. Detailed knowledge about the interactions between micro-structure of ice and its deformation is needed to assess the integrity of stratigraphic layering and the depth-age relationship in ice cores, which is essential for interpreting the paleoclimate record. The Principal Investigators will use micro-structure to study fabric, the orientation distribution of crystal c-axes, and texture, the size and shape of crystals. Numerical modeling of ice deformation is a useful tool in understanding these interactions. Accurate modeling of ice deformation is complicated by factors, such as the fabric, grain size, dynamic recrystallization, stress level, and precise knowledge of initial conditions. For example, ice fabric evolves as the ice is strained and the deformation depends on the fabric. This complicated feedback mechanism must be understood to correctly model ice deformation. In another example, the usual assumption is that the initial fabric is isotropic or random, but there are excellent examples of near-surface ice in the ice cores that are apparently not isotropic. One must know the initial fabric to calculate the deformation rate in ice sheets. Dr. Wilen will combine results of his new automatic fabric analyzer (AFA) with predictions of detailed ice deformation models (Dr. Thorsteinsson) to refine and better constrain such models. The AFA gives new information in thin sections because the precision and number of measured c-axis orientations are greatly improved. The Principal Investigators will analyze existing data and collect new data on fabric and texture from ice cores to address questions regarding near-surface fabric, deformation mechanisms, dynamic recrystallization, and potential sources of layer disturbances. The data will be used to constrain models of fabric evolution and recrystallization processes. With the more refined models, scientists can address different questions and important problems related to ice deformation and ice cores. For example, the recent agreement between the climate records from the Greenland Ice Core Project (GRIP) and Greenland Ice Sheet Project 2 (GISP2) ice cores of the upper-90%, and the disagreement in the lower-10% emphasizes the need to understand and predict the mechanisms and probable depths of disruption in these and future deep ice cores. Evidence suggests that the stratigraphic disturbances arise from the anisotropic nature of ice crystals at a variety of scales. To properly model the deformation of anisotropic ice, the influence of fabric on deformation must be well known.

Siple Dome Glaciology and Ice Stream History

9316338

1999-01-01

Jacobel, Robert

Siple Dome Glaciology and Ice Stream History 1994, 1996

USAP-DC

USAP-DC

U.S. ANTARCTIC PROGRAM DATA CENTER

The Results Map and the Results Table

Defining a search area on the Results Map

Viewing map layers on the Results Map

Search USAP Projects And Datasets

Older retrieved projects from AMD. Warning: many have incomplete information.

To sort the table of search results, click the header of the column you wish to search by. To sort by multiple columns, hold down the shift key whilst selecting the sort columns in order.