USAP-DC

{"dp_type": "Dataset", "free_text": "East Antarctica"}

[{"awards": "2324092 MacKie, Emma", "bounds_geometry": ["POLYGON((95 -65,96 -65,97 -65,98 -65,99 -65,100 -65,101 -65,102 -65,103 -65,104 -65,105 -65,105 -65.7,105 -66.4,105 -67.1,105 -67.8,105 -68.5,105 -69.2,105 -69.9,105 -70.6,105 -71.3,105 -72,104 -72,103 -72,102 -72,101 -72,100 -72,99 -72,98 -72,97 -72,96 -72,95 -72,95 -71.3,95 -70.6,95 -69.9,95 -69.2,95 -68.5,95 -67.8,95 -67.1,95 -66.4,95 -65.7,95 -65))"], "date_created": "Mon, 21 Apr 2025 00:00:00 GMT", "description": "This dataset is a result of a study which uses Monte Carlo Markov Chain and geostatistics to infer subglacial topography from sparse bed elevation measurements. The dataset consists of 40 equally probable realizations of subglacial topography in the Denman region. Each of the realizations is constrained by conservation of ice mass (mass conservation), complies with bed elevation measurements from bedmap3 dataset, and has a realistic topographic roughness. The topography has 1 kilometer times 1 kilometer resolution on a regular grid in polar stereographic projection (EPSG 3412).", "east": 105.0, "geometry": ["POINT(100 -68.5)"], "keywords": "Antarctica; Cryosphere; Denman Glacier; East Antarctica; Geostatistics; Ice Thickness; MCMC; Model Data; Monte Carlo Markov Chain; Subglacial Topography", "locations": "East Antarctica; Antarctica; Denman Glacier", "north": -65.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "persons": "Shao, Niya; MacKie, Emma; Michael, Field; McCormack, Felicity", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -72.0, "title": "Ensemble of subglacial topography beneath Denman Glacier generated by geostatistical Monte Carlo Markov Chain under mass conservation principle", "uid": "601927", "west": 95.0}, {"awards": "2423761 Blackburn, Terrence; 2042495 Blackburn, Terrence", "bounds_geometry": ["POLYGON((-180 -75,-144 -75,-108 -75,-72 -75,-36 -75,0 -75,36 -75,72 -75,108 -75,144 -75,180 -75,180 -76.5,180 -78,180 -79.5,180 -81,180 -82.5,180 -84,180 -85.5,180 -87,180 -88.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -88.5,-180 -87,-180 -85.5,-180 -84,-180 -82.5,-180 -81,-180 -79.5,-180 -78,-180 -76.5,-180 -75))"], "date_created": "Mon, 17 Mar 2025 00:00:00 GMT", "description": "This dataset includes geochemical analyses of carbonate nodules collected at Elephant Moraine and the Pensacola Mountains, East Antarctica. Oxygen and uranium-series isotope analyses indicate that these carbonates precipitated from glacial meltwater during deglacial periods in the late Pleistocene. Carbonate \u03b413C values as low as -32.75 \u2030 identify thermogenic methane as a primary carbon source, while clumped isotope measurements indicate formation temperatures of 12 - 20\u02daC, consistent with a geothermal origin. Lipid biomarker analyses further show that organic matter preserved in the nodules is highly thermally matured. These findings indicate that deep-sourced thermogenic methane migrated as hydrocarbon seeps to shallow pore spaces within basal sediments, demonstrating that geothermally active areas can be hotspots for methane accumulation below the Antarctic Ice Sheet. This material is based on services provided by the Polar Rock Repository with support from the National Science Foundation, under Cooperative Agreement OPP-2137467.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Carbon Isotopes; Cryosphere; East Antarctica; Elephant Moraine; Geochronology; Isotope Data; Subglacial", "locations": "Elephant Moraine; Antarctica; East Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Piccione, Gavin", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates; EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}, {"proj_uid": "p0010459", "repository": "USAP-DC", "title": "EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "uid": "601918", "west": -180.0}, {"awards": "2019719 Brook, Edward", "bounds_geometry": ["POLYGON((50 -84,55 -84,60 -84,65 -84,70 -84,75 -84,80 -84,85 -84,90 -84,95 -84,100 -84,100 -84.6,100 -85.2,100 -85.8,100 -86.4,100 -87,100 -87.6,100 -88.2,100 -88.8,100 -89.4,100 -90,95 -90,90 -90,85 -90,80 -90,75 -90,70 -90,65 -90,60 -90,55 -90,50 -90,50 -89.4,50 -88.8,50 -88.2,50 -87.6,50 -87,50 -86.4,50 -85.8,50 -85.2,50 -84.6,50 -84))"], "date_created": "Mon, 10 Mar 2025 00:00:00 GMT", "description": "This dataset contains the basal ice unit thickness as measured by the NSF COLDEX MARFA ice-penetrating radar survey, which mainly focuses on the southern flank of Dome A. The \"basal ice unit\" is hereby defined as the bottom portion of the ice sheet where no clear and traceable englacial reflection is detected by the radar sounder. Raw radar data can be found at: https://doi.org/10.15784/601768. The basal ice unit is mapped using the DecisionSpace Geosciences 10ep software package. This dataset provides three data products:\r\n\u003cbr/\u003e\u2022 Thickness of the basal ice unit\r\n\u003cbr/\u003e\u2022 Thickness of the stratigraphic ice unit above the basal ice unit\r\n\u003cbr/\u003e\u2022 The shape of the basal ice unit boundary, where rapid basal ice unit thinning is observed in the middle of the South Pole Basin.", "east": 100.0, "geometry": ["POINT(75 -87)"], "keywords": "Antarctica; Coldex; Cryosphere; East Antarctica; East Antarctic Plateau; Glaciology; Radar Echo Sounder", "locations": "Antarctica; East Antarctica; East Antarctic Plateau", "north": -84.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Yan, Shuai; Young, Duncan A.; Vega Gonzalez, Alejandra; Singh, Shivangini; Kerr, Megan; Blankenship, Donald D.", "project_titles": "Center for Oldest Ice Exploration", "projects": [{"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -90.0, "title": "Basal Ice Unit Thickness Mapped by the NSF COLDEX MARFA Ice Penetrating Radar", "uid": "601912", "west": 50.0}, {"awards": "2042495 Blackburn, Terrence", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Wed, 05 Mar 2025 00:00:00 GMT", "description": "This dataset contains U-series, d18O, d13C and 87Sr/86Sr data from 25 subglacial calcite precipitates from locations around the Antarctic ice sheet, primarily outlet glaciers near the ice sheet margins and nunataks in the Transantarctic mountains. Lat-lon data for each sample is given as well.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cryosphere", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Gagliardi, Jessica", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Subglacial precipitates record Antarctic ice sheet response to Southern Ocean warming ", "uid": "601911", "west": -180.0}, {"awards": "2201129 Fischer, Karen", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Wed, 12 Feb 2025 00:00:00 GMT", "description": "This dataset contains crustal thickness measurements at 99 individual broadband seismic stations across Antarctica derived from teleseismic Sp waves. Crustal thickness estimates were obtained by measuring the depth of the Sp phase associated with the crust-mantle boundary observed in single-station stacks of Sp receiver functions. The measurements offer new constraints on crustal structure in West and East Antarctica. Comparison with crustal thickness estimates from prior studies are provided in the associated journal article (see References).", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Crust; Cryosphere; Moho", "locations": "Antarctica; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Brown, Sarah; Fischer, Karen", "project_titles": "Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity", "projects": [{"proj_uid": "p0010339", "repository": "USAP-DC", "title": "Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Crustal thicknesses in Antarctica from Sp receiver functions", "uid": "601898", "west": -180.0}, {"awards": "2201129 Fischer, Karen", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Wed, 12 Feb 2025 00:00:00 GMT", "description": "This dataset contains the depths of negative velocity gradients that are potentially interpretable as the lithosphere-asthenosphere boundary (LAB) beneath Antarctica, derived from common conversion point stacking of Sp receiver functions. The dataset provides constraints on lithospheric thickness variations, particularly in West Antarctica, where a vertically localized LAB is observed at depths of 70\u2013100 km. In East Antarctica, two zones of well-defined LAB depths are present in regions near the coast at depths of 75-110 km (~140\u02daE) and 90-130 km (~115\u02daE). Interpretation of these results and comparison with prior studies are provided in the associated journal article (see References).", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cryosphere; LAB; Lithosphere; Lithospheric Thickness", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Brown, Sarah; Fischer, Karen", "project_titles": "Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity", "projects": [{"proj_uid": "p0010339", "repository": "USAP-DC", "title": "Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Lithospheric thicknesses in Antarctica from Sp receiver functions", "uid": "601899", "west": -180.0}, {"awards": "2149518 Fudge, Tyler; 2019719 Brook, Edward", "bounds_geometry": ["POINT(159.36 -76.73)"], "date_created": "Fri, 06 Dec 2024 00:00:00 GMT", "description": "This dataset includes three-dimensional multitrack electrical conductivity measurements (3D ECM) results from measurements in the upper sections of the ALHIC2201 and ALHIC2302 large (241mm) diameter ice cores drilled in the Allan Hills blue ice area (76.73\u00b0S,159.36\u00b0E) in Victoria Land, East Antarctica. The data extends from the surface to 23.0 m depth in ALHIC2201 and from 8.5 m to 46.3 m depth in ALHIC2302. We include the raw 3D ECM data (AC and DC multitrack ECM measurements on perpendicular faces of a quarter-core cut) in CSV format and basic plots of this data. We also provide dip and dip direction estimates of the layering observed in each core section in a CSV table.", "east": 159.36, "geometry": ["POINT(159.36 -76.73)"], "keywords": "Allan Hills; Antarctica; Cryosphere", "locations": "Antarctica; Allan Hills", "north": -76.73, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Kirkpatrick, Liam; Carter, Austin; Marks Peterson, Julia; Shackleton, Sarah; Fudge, T. J.", "project_titles": "Center for Oldest Ice Exploration; Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections", "projects": [{"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}, {"proj_uid": "p0010365", "repository": "USAP-DC", "title": "Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -76.73, "title": "ALHIC2201 and ALHIC2302 3D ECM and Layer Orientations", "uid": "601854", "west": 159.36}, {"awards": "2042495 Blackburn, Terrence; 1644171 Blackburn, Terrence", "bounds_geometry": ["POLYGON((161.9 -77.65,161.96 -77.65,162.02 -77.65,162.08 -77.65,162.14000000000001 -77.65,162.2 -77.65,162.26 -77.65,162.32 -77.65,162.38 -77.65,162.44 -77.65,162.5 -77.65,162.5 -77.66000000000001,162.5 -77.67,162.5 -77.68,162.5 -77.69,162.5 -77.7,162.5 -77.71000000000001,162.5 -77.72,162.5 -77.73,162.5 -77.74,162.5 -77.75,162.44 -77.75,162.38 -77.75,162.32 -77.75,162.26 -77.75,162.2 -77.75,162.14000000000001 -77.75,162.08 -77.75,162.02 -77.75,161.96 -77.75,161.9 -77.75,161.9 -77.74,161.9 -77.73,161.9 -77.72,161.9 -77.71000000000001,161.9 -77.7,161.9 -77.69,161.9 -77.68,161.9 -77.67,161.9 -77.66000000000001,161.9 -77.65))"], "date_created": "Mon, 01 Jul 2024 00:00:00 GMT", "description": "This dataset contains uranium and thorium isotopic compositions (U-234, U-235, U-238, Th-230, Th-232) and major element compositions (Al, K, Na, Ca, Fe, Mn, reported as oxides) for silicate sediments from glaciogenic drifts associated with advances of Taylor Glacier in Taylor Valley, Antarctica. Isotopic measurements were obtained by ID-TIMS in the Keck Isotope Facility at UC Santa Cruz and elemental measurements were obtained by ICP-OES in the Plasma Analytical Laboratory. All measurements include fully propagated analytical and systematic (e.g. isotopic tracer) uncertainties. Chemical index of alteration was calculated from major element data. Prior to measurements, sediments were sieved to \u2264125 \u03bcm grain sizes, separated into quartz-feldspar-rich and clay-rich aliquots by hydraulic settling, and subjected to sequential chemical extractions (\"leaching\") prior to silicate digestion.", "east": 162.5, "geometry": ["POINT(162.2 -77.7)"], "keywords": "Antarctica; Cryosphere; Erosion; Isotope Data; Major Elements; Soil; Taylor Glacier; Taylor Valley", "locations": "Taylor Valley; Taylor Glacier; Antarctica", "north": -77.65, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Edwards, Graham; Piccione, Gavin; Blackburn, Terrence; Tulaczyk, Slawek", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates; U-Series Comminution Age Constraints on Taylor Valley Erosion", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}, {"proj_uid": "p0010243", "repository": "USAP-DC", "title": "U-Series Comminution Age Constraints on Taylor Valley Erosion"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.75, "title": "U-Th isotopes and major elements in sediments from Taylor Valley, Antarctica", "uid": "601806", "west": 161.9}, {"awards": "1914698 Hansen, Samantha", "bounds_geometry": ["POLYGON((148 -71.5,150.4 -71.5,152.8 -71.5,155.2 -71.5,157.6 -71.5,160 -71.5,162.4 -71.5,164.8 -71.5,167.2 -71.5,169.6 -71.5,172 -71.5,172 -72.15,172 -72.8,172 -73.45,172 -74.1,172 -74.75,172 -75.4,172 -76.05,172 -76.7,172 -77.35,172 -78,169.6 -78,167.2 -78,164.8 -78,162.4 -78,160 -78,157.6 -78,155.2 -78,152.8 -78,150.4 -78,148 -78,148 -77.35,148 -76.7,148 -76.05,148 -75.4,148 -74.75,148 -74.1,148 -73.45,148 -72.8,148 -72.15,148 -71.5))"], "date_created": "Wed, 24 Jan 2024 00:00:00 GMT", "description": "As seismic data availability increases, the necessity for automated processing techniques has become increasingly evident. Expanded geophysical datasets collected over the past several decades across Antarctica provide excellent resources to evaluate different event detection approaches. We have used the traditional Short-Term Average/Long-Term Average (STA/LTA) algorithm to catalogue seismic data recorded by 19 stations in East Antarctica between 2012 and 2015. However, the complexities of the East Antarctic dataset, including low magnitude events and phenomena such as icequakes, warrant more advanced automated detection techniques. Therefore, we have also applied template matching as well as several deep learning algorithms, including Generalized Phase Detection (GPD), PhaseNet, BasicPhaseAE, and EQTransformer (EQT), to identify seismic phases within our dataset. Our goal was not only to increase the volume of detectable seismic events but also to gain insights into the effectiveness of these different automated approaches. Our assessment evaluated the completeness of the newly generated catalogs, the precision of identified event locations, and the quality of the picks. The final events corresponding to each of our three catalogs (based on STA/LTA, template matching, and machine learning, respectively) are listed in the provided files.", "east": 172.0, "geometry": ["POINT(160 -74.75)"], "keywords": "Antarctica; Geoscientificinformation; Machine Learning; Seismic Event Detection; Seismology; Seismometer", "locations": "Antarctica", "north": -71.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hansen, Samantha; Ho, Long; Walter, Jacob", "project_titles": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)", "projects": [{"proj_uid": "p0010204", "repository": "USAP-DC", "title": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "East Antarctic Seismicity from different Automated Event Detection Algorithms", "uid": "601762", "west": 148.0}, {"awards": "1914698 Hansen, Samantha", "bounds_geometry": ["POLYGON((90 -65,99 -65,108 -65,117 -65,126 -65,135 -65,144 -65,153 -65,162 -65,171 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,171 -90,162 -90,153 -90,144 -90,135 -90,126 -90,117 -90,108 -90,99 -90,90 -90,90 -87.5,90 -85,90 -82.5,90 -80,90 -77.5,90 -75,90 -72.5,90 -70,90 -67.5,90 -65))"], "date_created": "Wed, 24 Jan 2024 00:00:00 GMT", "description": "Recent investigations in polar environments have examined solid-Earth-ice-sheet feedbacks and have emphasized that glacial isostatic adjustment, tectonic, and geothermal forcings exert first-order control on the physical conditions at and below the ice-bed interface and must be taken into account when evaluating ice-sheet evolution. However, the solid-Earth structure beneath much of Antarctica is still poorly constrained given the sparse distribution of seismic stations across the continent and the generally low seismicity rate. One region of particular interest is the Wilkes Subglacial Basin (WSB) in East Antarctica. During the mid-Pliocene warm period, the WSB may have contributed 3-4 m to the estimated 20 m rise in sea-level, indicating that this region could also play an important role in future warming scenarios. However, the WSB may have experienced notable bedrock uplift since the Pliocene; therefore, past geologic inferences of instability may not serve as a simple analogue for the future.\r\n\r\nUsing records of ambient seismic noise recorded by both temporary and long-term seismic networks, along with a full-waveform tomographic inversion technique, we have developed improved images of the lithospheric structure beneath East Antarctica, including the WSB. Empirical Green\u2019s Functions with periods between 40 and 340 s have been extracted using a frequency-time normalization technique, and a finite-difference approach with a spherical grid has been employed to numerically model synthetic seismograms. Associated sensitivity kernels have also been constructed using a scattering integral method. Our results suggest the WSB is underlain by slow seismic velocities, with faster seismic structure beneath the adjacent Transantarctic Mountains and the Belgica Subglacial Highlands. This may indicate that the WSB is associated with a region of thinner lithosphere, possibly associated with prior continental rifting. The seismic heterogeneity highlighted in our model could have significant implications for understanding the geodynamic origin of WSB topography and its influence on ice-sheet behavior.\r\n\r\nThe model file and associated plotting scripts are provided.", "east": 180.0, "geometry": ["POINT(135 -77.5)"], "keywords": "Ambient Noise; Antarctica; East Antarctica; Geoscientificinformation; Seismic Tomography; Seismology", "locations": "East Antarctica; Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hansen, Samantha; Emry, Erica", "project_titles": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)", "projects": [{"proj_uid": "p0010204", "repository": "USAP-DC", "title": "Collaborative Research: Resolving earth structure influence on ice-sheet stability in the Wilkes\r\nSubglacial Basin (RESISSt)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Full Waveform Ambient Noise Tomography for East Antarctica", "uid": "601763", "west": 90.0}, {"awards": "1744649 Christianson, Knut", "bounds_geometry": ["POLYGON((-120 -85.5,-116.67 -85.5,-113.34 -85.5,-110.01 -85.5,-106.68 -85.5,-103.35 -85.5,-100.02000000000001 -85.5,-96.69 -85.5,-93.36 -85.5,-90.03 -85.5,-86.7 -85.5,-86.7 -85.95,-86.7 -86.4,-86.7 -86.85,-86.7 -87.3,-86.7 -87.75,-86.7 -88.2,-86.7 -88.65,-86.7 -89.1,-86.7 -89.55,-86.7 -90,-90.03 -90,-93.36 -90,-96.69 -90,-100.02 -90,-103.35 -90,-106.68 -90,-110.01 -90,-113.34 -90,-116.67 -90,-120 -90,-120 -89.55,-120 -89.1,-120 -88.65,-120 -88.2,-120 -87.75,-120 -87.3,-120 -86.85,-120 -86.4,-120 -85.95,-120 -85.5))"], "date_created": "Fri, 21 Jul 2023 00:00:00 GMT", "description": "This dataset consists of gridded basal topographies in the vicinity of Hercules Dome, East Antarctica generated from multi-element ice-penetrating radar data. ", "east": -86.7, "geometry": ["POINT(-103.35 -87.75)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "locations": "Antarctica; Hercules Dome; Antarctica", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hoffman, Andrew; Holschuh, Nicholas; Paden, John; Christianson, Knut", "project_titles": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "projects": [{"proj_uid": "p0010359", "repository": "USAP-DC", "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Hercules Dome Ice Core", "south": -90.0, "title": "Hercules Dome Ice-Penetrating Radar Swath Topographies", "uid": "601711", "west": -120.0}, {"awards": "1744649 Christianson, Knut", "bounds_geometry": ["POLYGON((-120 -85.5,-116.67 -85.5,-113.34 -85.5,-110.01 -85.5,-106.68 -85.5,-103.35 -85.5,-100.02000000000001 -85.5,-96.69 -85.5,-93.36 -85.5,-90.03 -85.5,-86.7 -85.5,-86.7 -85.95,-86.7 -86.4,-86.7 -86.85,-86.7 -87.3,-86.7 -87.75,-86.7 -88.2,-86.7 -88.65,-86.7 -89.1,-86.7 -89.55,-86.7 -90,-90.03 -90,-93.36 -90,-96.69 -90,-100.02 -90,-103.35 -90,-106.68 -90,-110.01 -90,-113.34 -90,-116.67 -90,-120 -90,-120 -89.55,-120 -89.1,-120 -88.65,-120 -88.2,-120 -87.75,-120 -87.3,-120 -86.85,-120 -86.4,-120 -85.95,-120 -85.5))"], "date_created": "Thu, 20 Jul 2023 00:00:00 GMT", "description": "This dataset contains high-frequency impulse radar data collected at western Hercules Dome in East Antarctica.", "east": -86.7, "geometry": ["POINT(-103.35 -87.75)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hercules Dome; Ice Penetrating Radar; Snow/ice; Snow/Ice", "locations": "Antarctica; Antarctica; Hercules Dome", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hoffman, Andrew; Christianson, Knut; Hills, Benjamin; Christian, John; Holschuh, Nicholas; Horlings, Annika; O\u0027Connor, Gemma", "project_titles": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "projects": [{"proj_uid": "p0010359", "repository": "USAP-DC", "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Hercules Dome Ice Core", "south": -90.0, "title": "Hercules Dome High-Frequency Impulse Ice-Penetrating Radar Data", "uid": "601710", "west": -120.0}, {"awards": "1643716 Buizert, Christo", "bounds_geometry": ["POLYGON((-180 -67,-144 -67,-108 -67,-72 -67,-36 -67,0 -67,36 -67,72 -67,108 -67,144 -67,180 -67,180 -69.3,180 -71.6,180 -73.9,180 -76.2,180 -78.5,180 -80.8,180 -83.1,180 -85.4,180 -87.7,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.7,-180 -85.4,-180 -83.1,-180 -80.8,-180 -78.5,-180 -76.2,-180 -73.9,-180 -71.6,-180 -69.3,-180 -67))"], "date_created": "Mon, 22 May 2023 00:00:00 GMT", "description": "We have reconstructed the atmospheric N2O mole fraction and its isotopic composition by combining data from ice cores, firn air, and atmospheric samples. The mole fraction reconstruction extends back to 1000 CE using ice cores, firn air, and atmospheric sampling; and the isotopic reconstruction extends back to 1900 CE using only firn air data. We have incorporated both newly measured and previously published data. We present new data for the mole fraction, d15Nbulk, d18O, and d15NSP values from the Styx (East Antarctica) firn air, and mole fraction from the North Greenland Eemian Ice drilling Project (NEEM) firn air. We have used published records from the Styx and NEEM ice cores, direct atmospheric measurements from the NOAA global sampling network, and firn air data, giving a total of 11 sites for N2O mole fraction, 12 sites for d15Nbulk, 11 sites for d18O, and 8 sites for d15NSP values.\r\n", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctic; Antarctica; Anthropogenic Emission; Atmosphere; Greenhouse Gas; Greenland; Ice Core Data; Nitrification And Denitrification Processes; Nitrous Oxide; Site-Specific 15N Isotopomer; Styx Glacier", "locations": "Antarctica; Styx Glacier; Antarctic; Greenland", "north": -67.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Ghosh, Sambit; Toyoda, Sakae ; Buizert, Christo ; Langenfelds, Ray L ; Yoshida, Naohiro ; Joong Kim, Seong; Ahn, Jinho ; Etheridge, David", "project_titles": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability", "projects": [{"proj_uid": "p0010341", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Concentration and isotopic composition of atmospheric N2O over the last century", "uid": "601693", "west": -180.0}, {"awards": "1744649 Christianson, Knut", "bounds_geometry": ["POLYGON((-120 -85.5,-116.67 -85.5,-113.34 -85.5,-110.01 -85.5,-106.68 -85.5,-103.35 -85.5,-100.02000000000001 -85.5,-96.69 -85.5,-93.36 -85.5,-90.03 -85.5,-86.7 -85.5,-86.7 -85.95,-86.7 -86.4,-86.7 -86.85,-86.7 -87.3,-86.7 -87.75,-86.7 -88.2,-86.7 -88.65,-86.7 -89.1,-86.7 -89.55,-86.7 -90,-90.03 -90,-93.36 -90,-96.69 -90,-100.02 -90,-103.35 -90,-106.68 -90,-110.01 -90,-113.34 -90,-116.67 -90,-120 -90,-120 -89.55,-120 -89.1,-120 -88.65,-120 -88.2,-120 -87.75,-120 -87.3,-120 -86.85,-120 -86.4,-120 -85.95,-120 -85.5))"], "date_created": "Wed, 07 Sep 2022 00:00:00 GMT", "description": "This dataset contains high-frequency impulse radar data collected at western Hercules Dome in East Antarctica. ", "east": -86.7, "geometry": ["POINT(-103.35 -87.75)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Ice Penetrating Radar; Snow/ice; Snow/Ice", "locations": "Antarctica", "north": -85.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Christianson, Knut", "project_titles": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "projects": [{"proj_uid": "p0010359", "repository": "USAP-DC", "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets", "uid": "601606", "west": -120.0}, {"awards": "2042495 Blackburn, Terrence", "bounds_geometry": null, "date_created": "Wed, 10 Aug 2022 00:00:00 GMT", "description": "This file includes U-series isotopic and 234U/230Th chronologic data from two chemical precipitates deposited beneath the Antarctic Ice Sheet. Precipitate mineral compositions consist of opal and calcite layers. Sample MA113 was found at Mount Achernar moraine (84.2\u00b0S, 161\u00b0E), and sample PRR50489 was found at Elephant Moraine (76.3\u00b0S, 157.3\u00b0E).", "east": null, "geometry": null, "keywords": "Antarctica; East Antarctica", "locations": "Antarctica; East Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Piccione, Gavin; Blackburn, Terrence", "project_titles": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates", "projects": [{"proj_uid": "p0010192", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing East Antarctica\u2019s Past Response to Climate using Subglacial Precipitates"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Subglacial Precipitates Record Antarctic Ice Sheet Response to Pleistocene Millennial Climate Cycles", "uid": "601594", "west": null}, {"awards": "1246407 Jenouvrier, Stephanie; 1840058 Jenouvrier, Stephanie", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Mon, 27 Jun 2022 00:00:00 GMT", "description": "Individuals differ in many ways. Most produce few offspring; a handful produce many. Some\r\ndie early; others live to old age. It is tempting to attribute these differences in outcomes to differences in individual traits, and thus in the demographic rates experienced. However, there is\r\nmore to individual variation than meets the eye of the biologist. Even among individuals sharing identical traits, life history outcomes (life expectancy and lifetime reproduction) will vary due\r\nto individual stochasticity, i.e., to chance. Quantifying the contributions of heterogeneity and\r\nchance is essential to understanding natural variability. Inter-individual differences vary across environmental conditions, hence heterogeneity and stochasticity depend on environmental conditions. We show that favorable conditions increase the contributions of individual stochasticity, and reduce the contributions of heterogeneity, to variance in demographic outcomes in a seabird population. The opposite is true under poor conditions. This result has important consequence for understanding the ecology and evolution of life history strategies.\r\n\r\nSpecifically, three life-history complexes exist in a population of southern fulmar (defined as sets of life-history characteristics that occur together through the lifetime of an individual). They are reminiscent of the gradient of life- history strategy observed among species:\r\n\r\n1. Group 1 (14% of offspring at fledging) is a slow-paced life history where individuals tend to delay recruitment, recruit successfully, and extend their reproductive lifespan.\r\n2. Group 2 (67% of offspring at fledging) consists of individuals that are less likely to recruit, have high adult survival, and skip breeding often.\r\n3. Group 3 (19% of offspring at fledging) is a fast-paced life history where individuals recruit early and attempt to breed often but have a short lifespan.\r\n\r\nIndividuals in groups 1 and 3 are considered \u201chigh-quality\u201d individuals because they produce, on average, more offspring over their lives than do individuals in group 2. But group 2 is made-up of individuals that experience the highest levels of adult survival.\r\n \r\nDifferences between these groups, i.e. individual heterogeneity, only explains a small fraction of variance in life expectancy (5.9%) and lifetime reproduction (22%) when environmental conditions are ordinary. We expect that the environmental context experienced, especially when environmental conditions get extreme, is key to characterizing individual heterogeneity and its contribution to life history outcomes. Here, we build on previous studies to quantify the impact of extreme environmental conditions on the relative contributions of individual heterogeneity and stochasticity to variance in life history outcomes.\r\nWe found that the differences in vital rates and demographic outcomes among complexes depend on the sea ice conditions individuals experience. Importantly, differences across life history complexes are amplified when sea ice concentration get extremely low. Sea ice conditions did not only affect patterns of life history traits, but also the variance of life history outcomes and the relative proportion of individual unobserved heterogeneity to the total variance. These new results advance the current debate on the relative importance heterogeneity (i.e. potentially adaptive) and stochasticity (i.e. enhances genetic drift) in shaping potentially neutral vs. adaptive changes in life histories.\r\n", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Biota; Birds; East Antarctica; Southern Fulmar", "locations": "Antarctica; East Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Jenouvrier, Stephanie", "project_titles": "Linking Foraging Behaviors to Demography to understand Albatrosses Population Responses to Climate Change; Polar Seabirds with Long-term Pair Bonds: Effects of Mating on Individual Fitness and Population Dynamics", "projects": [{"proj_uid": "p0010090", "repository": "USAP-DC", "title": "Polar Seabirds with Long-term Pair Bonds: Effects of Mating on Individual Fitness and Population Dynamics"}, {"proj_uid": "p0010002", "repository": "USAP-DC", "title": "Linking Foraging Behaviors to Demography to understand Albatrosses Population Responses to Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Demographic outputs and their variances for three life history complexes for the Southern Fulmar across contrasted sea ice conditions.", "uid": "601585", "west": -180.0}, {"awards": "1946326 Doran, Peter", "bounds_geometry": ["POLYGON((163.079602 -77.585467,163.1197073 -77.585467,163.1598126 -77.585467,163.1999179 -77.585467,163.2400232 -77.585467,163.2801285 -77.585467,163.3202338 -77.585467,163.3603391 -77.585467,163.4004444 -77.585467,163.4405497 -77.585467,163.480655 -77.585467,163.480655 -77.5924303,163.480655 -77.5993936,163.480655 -77.6063569,163.480655 -77.6133202,163.480655 -77.6202835,163.480655 -77.6272468,163.480655 -77.6342101,163.480655 -77.6411734,163.480655 -77.6481367,163.480655 -77.6551,163.4405497 -77.6551,163.4004444 -77.6551,163.3603391 -77.6551,163.3202338 -77.6551,163.2801285 -77.6551,163.2400232 -77.6551,163.1999179 -77.6551,163.1598126 -77.6551,163.1197073 -77.6551,163.079602 -77.6551,163.079602 -77.6481367,163.079602 -77.6411734,163.079602 -77.6342101,163.079602 -77.6272468,163.079602 -77.6202835,163.079602 -77.6133202,163.079602 -77.6063569,163.079602 -77.5993936,163.079602 -77.5924303,163.079602 -77.585467))"], "date_created": "Wed, 09 Feb 2022 00:00:00 GMT", "description": "Location and metadata of C-14 samples from Taylor Valley, East Antarctica", "east": 163.480655, "geometry": ["POINT(163.2801285 -77.6202835)"], "keywords": "Antarctica; Carbon-14; Sample/collection Description; Sample/Collection Description; Sample Location; Taylor Valley", "locations": "Taylor Valley; Antarctica", "north": -77.585467, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Doran, Peter; Stone, Michael", "project_titles": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers", "projects": [{"proj_uid": "p0010294", "repository": "USAP-DC", "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.6551, "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: in situ 14C data", "uid": "601521", "west": 163.079602}, {"awards": "1946326 Doran, Peter", "bounds_geometry": ["POLYGON((163.093642 -77.592484,163.1049267 -77.592484,163.1162114 -77.592484,163.1274961 -77.592484,163.1387808 -77.592484,163.1500655 -77.592484,163.1613502 -77.592484,163.1726349 -77.592484,163.1839196 -77.592484,163.1952043 -77.592484,163.206489 -77.592484,163.206489 -77.5986389,163.206489 -77.6047938,163.206489 -77.6109487,163.206489 -77.6171036,163.206489 -77.6232585,163.206489 -77.6294134,163.206489 -77.6355683,163.206489 -77.6417232,163.206489 -77.6478781,163.206489 -77.654033,163.1952043 -77.654033,163.1839196 -77.654033,163.1726349 -77.654033,163.1613502 -77.654033,163.1500655 -77.654033,163.1387808 -77.654033,163.1274961 -77.654033,163.1162114 -77.654033,163.1049267 -77.654033,163.093642 -77.654033,163.093642 -77.6478781,163.093642 -77.6417232,163.093642 -77.6355683,163.093642 -77.6294134,163.093642 -77.6232585,163.093642 -77.6171036,163.093642 -77.6109487,163.093642 -77.6047938,163.093642 -77.5986389,163.093642 -77.592484))"], "date_created": "Wed, 09 Feb 2022 00:00:00 GMT", "description": "Location and metadata of samples collected from perched delta deposits along modern stream channels in lower Taylor Valley. Sample collection used equipment and followed procedures from the Desert Research Institute Luminescence Laboratory in Reno, NV.", "east": 163.206489, "geometry": ["POINT(163.1500655 -77.6232585)"], "keywords": "Antarctica; Sample/collection Description; Sample/Collection Description; Sample Location; Taylor Valley", "locations": "Antarctica; Taylor Valley", "north": -77.592484, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Doran, Peter; Stone, Michael", "project_titles": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers", "projects": [{"proj_uid": "p0010294", "repository": "USAP-DC", "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LTER", "south": -77.654033, "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: Infrared Stimulated Luminescence data", "uid": "601520", "west": 163.093642}, {"awards": "1746148 Sirovic, Ana", "bounds_geometry": ["POLYGON((143.6 -65,143.99 -65,144.38 -65,144.77 -65,145.16 -65,145.55 -65,145.94 -65,146.33 -65,146.72 -65,147.11 -65,147.5 -65,147.5 -65.12,147.5 -65.24,147.5 -65.36,147.5 -65.48,147.5 -65.6,147.5 -65.72,147.5 -65.84,147.5 -65.96,147.5 -66.08,147.5 -66.2,147.11 -66.2,146.72 -66.2,146.33 -66.2,145.94 -66.2,145.55 -66.2,145.16 -66.2,144.77 -66.2,144.38 -66.2,143.99 -66.2,143.6 -66.2,143.6 -66.08,143.6 -65.96,143.6 -65.84,143.6 -65.72,143.6 -65.6,143.6 -65.48,143.6 -65.36,143.6 -65.24,143.6 -65.12,143.6 -65))"], "date_created": "Wed, 21 Jul 2021 00:00:00 GMT", "description": "Logs of cetacean calls recorded using High-frequency Acoustic Recording Package (HARP) deployed in February 2019 off East Antarctica. Log includes blue whale, fin whale, humbpack whale, killer whale, long-finned pilot whale calls, whistles and echolocations.", "east": 147.5, "geometry": ["POINT(145.55 -65.6)"], "keywords": "Antarctica; East Antarctica", "locations": "East Antarctica; Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Sirovic, Ana", "project_titles": "EAGER: Collaborative Research: Acoustic Ecology of Foraging Antarctic Blue Whales in the Vicinity of Antarctic Krill", "projects": [{"proj_uid": "p0010228", "repository": "USAP-DC", "title": "EAGER: Collaborative Research: Acoustic Ecology of Foraging Antarctic Blue Whales in the Vicinity of Antarctic Krill"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -66.2, "title": "Passive acoustic recording metadata from East Antarctica, Feb 2019", "uid": "601465", "west": 143.6}, {"awards": "1443556 Thomson, Stuart", "bounds_geometry": ["POLYGON((-180 -83.5,-178 -83.5,-176 -83.5,-174 -83.5,-172 -83.5,-170 -83.5,-168 -83.5,-166 -83.5,-164 -83.5,-162 -83.5,-160 -83.5,-160 -83.75,-160 -84,-160 -84.25,-160 -84.5,-160 -84.75,-160 -85,-160 -85.25,-160 -85.5,-160 -85.75,-160 -86,-162 -86,-164 -86,-166 -86,-168 -86,-170 -86,-172 -86,-174 -86,-176 -86,-178 -86,180 -86,179 -86,178 -86,177 -86,176 -86,175 -86,174 -86,173 -86,172 -86,171 -86,170 -86,170 -85.75,170 -85.5,170 -85.25,170 -85,170 -84.75,170 -84.5,170 -84.25,170 -84,170 -83.75,170 -83.5,171 -83.5,172 -83.5,173 -83.5,174 -83.5,175 -83.5,176 -83.5,177 -83.5,178 -83.5,179 -83.5,-180 -83.5))"], "date_created": "Tue, 13 Jul 2021 00:00:00 GMT", "description": "List of supplementary tables from publication\r\nHe, J., Thomson, S.N., Reiners, P.W., Hemming, S.R., and Licht, K.J., 2021, Rapid erosion of the central Transantarctic Mountains at the Eocene-Oligocene transition: Evidence from skewed (U-Th)/He date distributions near Beardmore Glacier: Earth and Planetary Science Letters, v. 567, p. 117009, doi:10.1016/j.epsl.2021.117009.\r\n\r\nSupp. Table 1 U-Th/He data\r\nSupp. Table 2 Trace and REE data\r\nSupp. Table 3 Compilation with elevation-weighted resampling\r\nSupp. Table 4 Summary statistics and sampling distribution of large-n samples and compilations.\r\nSupp. Table 5 Perpendicular distance of BAR and CMK sample to Kukri Peneplain\r\nSupp. Table 6 Compilation of apatite He data from east Antarctica used in Fig. 1\r\n", "east": -160.0, "geometry": ["POINT(-175 -84.75)"], "keywords": "Antarctica; Beardmore Glacier; Erosion; Landscape Evolution; Shackleton Glacier; Transantarctic Mountains; (U-Th)/He", "locations": "Beardmore Glacier; Antarctica; Transantarctic Mountains; Shackleton Glacier", "north": -83.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Thomson, Stuart; He, John; Reiners, Peter; Hemming, Sidney R.; Licht, Kathy", "project_titles": "Collaborative Research: East Antarctic Glacial Landscape Evolution (EAGLE): A Study using Combined Thermochronology, Geochronology and Provenance Analysis", "projects": [{"proj_uid": "p0010188", "repository": "USAP-DC", "title": "Collaborative Research: East Antarctic Glacial Landscape Evolution (EAGLE): A Study using Combined Thermochronology, Geochronology and Provenance Analysis"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -86.0, "title": "Apatite (U-Th)/He and TREE Data Central Transantarctic Mountains", "uid": "601462", "west": 170.0}, {"awards": "0838842 Passchier, Sandra", "bounds_geometry": ["POINT(167.0833 -77.8889)"], "date_created": "Mon, 14 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of particle-size distributions on four intervals of diamicitites from ANDRILL Site AND-2A. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2 and 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 167.0833, "geometry": ["POINT(167.0833 -77.8889)"], "keywords": "Antarctica; McMurdo Sound; Miocene; Particle Size; Pleistocene; Pliocene", "locations": "McMurdo Sound; Antarctica", "north": -77.8889, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Hansen, Melissa A.", "project_titles": "Determining Middle Miocene through Pliocene Changes in Paleo Ice-flow and Basal Ice Conditions in East Antarctica through Sedimentological Analyses of Core Samples", "projects": [{"proj_uid": "p0000147", "repository": "USAP-DC", "title": "Determining Middle Miocene through Pliocene Changes in Paleo Ice-flow and Basal Ice Conditions in East Antarctica through Sedimentological Analyses of Core Samples"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.8889, "title": "Particle-size measurements for diamictites AND-2A sediment core, McMurdo Sound", "uid": "601452", "west": 167.0833}, {"awards": "1443690 Young, Duncan", "bounds_geometry": ["POLYGON((-180 -86,-176.5 -86,-173 -86,-169.5 -86,-166 -86,-162.5 -86,-159 -86,-155.5 -86,-152 -86,-148.5 -86,-145 -86,-145 -86.4,-145 -86.8,-145 -87.2,-145 -87.6,-145 -88,-145 -88.4,-145 -88.8,-145 -89.2,-145 -89.6,-145 -90,-148.5 -90,-152 -90,-155.5 -90,-159 -90,-162.5 -90,-166 -90,-169.5 -90,-173 -90,-176.5 -90,180 -90,174.2 -90,168.4 -90,162.6 -90,156.8 -90,151 -90,145.2 -90,139.4 -90,133.6 -90,127.8 -90,122 -90,122 -89.6,122 -89.2,122 -88.8,122 -88.4,122 -88,122 -87.6,122 -87.2,122 -86.8,122 -86.4,122 -86,127.8 -86,133.6 -86,139.4 -86,145.2 -86,151 -86,156.8 -86,162.6 -86,168.4 -86,174.2 -86,-180 -86))"], "date_created": "Fri, 02 Apr 2021 00:00:00 GMT", "description": "Level 2 aerogeophysical data, derived from the HiCARS2 radar system and laser altimeter for the Titan Dome region of East Antarctica. The observations included are geo-referenced surface elevation, bed elevation, ice thickness, bed reflectivity, surface reflectivity, and dated internal reflecting horizon depths.", "east": -145.0, "geometry": ["POINT(168.5 -88)"], "keywords": "Airborne Laser Altimetry; Airborne Radar; Airplane; Antarctica; Bedrock Elevation; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Radar Echo Sounder; Surface Elevation; Titan Dome", "locations": "East Antarctica; Titan Dome; Antarctica", "north": -86.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Beem, Lucas H.; Young, Duncan A.; Greenbaum, Jamin; Ng, Gregory; Blankenship, Donald D.; Cavitte, Marie G. P; Jingxue, Guo; Bo, Sun; Young, Duncan", "project_titles": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)", "projects": [{"proj_uid": "p0010115", "repository": "USAP-DC", "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Titan Dome, East Antarctica, Aerogeophysical Survey", "uid": "601437", "west": 122.0}, {"awards": "1543452 Blankenship, Donald; 0733025 Blankenship, Donald; 1443690 Young, Duncan; 0636724 Blankenship, Donald", "bounds_geometry": ["POLYGON((80 -65,89 -65,98 -65,107 -65,116 -65,125 -65,134 -65,143 -65,152 -65,161 -65,170 -65,170 -66.5,170 -68,170 -69.5,170 -71,170 -72.5,170 -74,170 -75.5,170 -77,170 -78.5,170 -80,161 -80,152 -80,143 -80,134 -80,125 -80,116 -80,107 -80,98 -80,89 -80,80 -80,80 -78.5,80 -77,80 -75.5,80 -74,80 -72.5,80 -71,80 -69.5,80 -68,80 -66.5,80 -65))"], "date_created": "Mon, 24 Aug 2020 00:00:00 GMT", "description": "The International Collaborative Exploration of the Cryosphere though Airborne Profiling (ICECAP) collected five seasons of aerogeophysical data data through the NSFs International Polar Year and NASAs Operation Ice Bridge programs in East Antarctica, using the coherent HiCARS 60 MHz radar system. By comparing echo strengths for different focusing apertures, and accounting for the ranges and angles involved, we can derive the \"specularity content\" of the bed echo, a proxy for small scale bed roughness and a good indicator for subglacial water pressure in regions of distributed subglacial water (Schroeder et al., 2014, IEEE GRSL, 10.1109/LGRS.2014.2337878; IEEE; Dow et al., 2019, EPSL https://doi.org/10.1016/j.epsl.2019.115961). Specularity data are inherently noisy, so these products have been smoothed with a 1 km filter.", "east": 170.0, "geometry": ["POINT(125 -72.5)"], "keywords": "Antarctica; East Antarctica; ICECAP; Ice Penetrating Radar; Radar Echo Sounder; Radar Echo Sounding; Subglacial Hydrology", "locations": "Antarctica; East Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology", "persons": "Young, Duncan A.; Blankenship, Donald D.; Roberts, Jason; Siegert, Martin; van Ommen, Tas; Greenbaum, Jamin; Schroeder, Dustin", "project_titles": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP); Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System; East Antarctic Grounding Line Experiment (EAGLE); IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP)", "projects": [{"proj_uid": "p0000719", "repository": "USAP-DC", "title": "IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP)"}, {"proj_uid": "p0000174", "repository": "USAP-DC", "title": "Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System"}, {"proj_uid": "p0010115", "repository": "USAP-DC", "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)"}, {"proj_uid": "p0000254", "repository": "USAP-DC", "title": "East Antarctic Grounding Line Experiment (EAGLE)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "ICECAP Basal Interface Specularity Content Profiles: IPY and OIB", "uid": "601371", "west": 80.0}, {"awards": "1443690 Young, Duncan", "bounds_geometry": ["POLYGON((110 -68,113 -68,116 -68,119 -68,122 -68,125 -68,128 -68,131 -68,134 -68,137 -68,140 -68,140 -68.7,140 -69.4,140 -70.1,140 -70.8,140 -71.5,140 -72.2,140 -72.9,140 -73.6,140 -74.3,140 -75,137 -75,134 -75,131 -75,128 -75,125 -75,122 -75,119 -75,116 -75,113 -75,110 -75,110 -74.3,110 -73.6,110 -72.9,110 -72.2,110 -71.5,110 -70.8,110 -70.1,110 -69.4,110 -68.7,110 -68))"], "date_created": "Tue, 07 Jul 2020 00:00:00 GMT", "description": "These aerogeophysical data were collected during the seventh ICECAP field season in 2015-16, and interpreted as part of the SPICECAP project. They consist of 7 survey flights using a BT-67 Basler and the ICECAP aergeophysical suite. The flights were based out of Australia\u0027s Casey Station and France/Italy\u0027s Concordia Station in East Antarctica, as part of a focused survey of the \u0027Little Dome C\u0027, a region with a suspected 1.5 Ma ice core record. The Level 2 data here consist of ice thickness, bed elevation and surface and bed reflectivity data, bed specularity content data, unleveled magnetic anomaly data, unleveled gravity anomaly data, and laser altimetry. Formats are self documented text files parallel those used by ICECAP (found in the Operation IceBridge archive at the National Snow and Ice Data Center), GIMBLE (found at USAP-DC), EAGLE-ICECAPII (found at the Australian Antarctic Data Center) and David Glacier (found on Zenodo.org), with summary maps of included data in PNG format.", "east": 140.0, "geometry": ["POINT(125 -71.5)"], "keywords": "Aerogeophysics; Antarctica; Bed Elevation; Bed Reflectivity; Epica Dome C; Ice Thickness", "locations": "Antarctica; Epica Dome C", "north": -68.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Young, Duncan A.; Roberts, Jason; Blankenship, Donald D.; van Ommen, Tas; Richter, Thomas; Greenbaum, Jamin; Cavitte, Marie G. P; Beem, Lucas H.; Quartini, Enrica; Tozer, Carly; Ng, Gregory; Habbal, Feras; Kempf, Scott D.; Ritz, Catherine", "project_titles": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)", "projects": [{"proj_uid": "p0010115", "repository": "USAP-DC", "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Dome C Ice Core", "south": -75.0, "title": "ICECAP: High resolution survey of the Little Dome C region in support of the IPICS Old Ice goal", "uid": "601355", "west": 110.0}, {"awards": "1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -61.130769444,-180 -62.261538888,-180 -63.392308332,-180 -64.523077776,-180 -65.65384722,-180 -66.784616664,-180 -67.915386108,-180 -69.046155552,-180 -70.176924996,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,180 -71.30769444,179.019305556 -71.30769444,178.038611112 -71.30769444,177.057916668 -71.30769444,176.077222224 -71.30769444,175.09652778 -71.30769444,174.115833336 -71.30769444,173.135138892 -71.30769444,172.154444448 -71.30769444,171.173750004 -71.30769444,170.19305556 -71.30769444,170.19305556 -70.176924996,170.19305556 -69.046155552,170.19305556 -67.915386108,170.19305556 -66.784616664,170.19305556 -65.65384722,170.19305556 -64.523077776,170.19305556 -63.392308332,170.19305556 -62.261538888,170.19305556 -61.130769444,170.19305556 -60,171.173750004 -60,172.154444448 -60,173.135138892 -60,174.115833336 -60,175.09652778 -60,176.077222224 -60,177.057916668 -60,178.038611112 -60,179.019305556 -60,-180 -60))"], "date_created": "Tue, 02 Jun 2020 00:00:00 GMT", "description": "We report new discoveries and radiocarbon dates on active and abandoned Ad\u00e9lie penguin (Pygoscelis adeliae) colonies at Cape Adare, Antarctica. This colony, first established at approximately 2000 BP (calendar years before present, i.e. 1950), is currently the largest for this species with approximately 338 000 breeding pairs, most located on lowlying Ridley Beach. We hypothesize that this colony first formed after fast ice began blocking open-water access by breeding penguins to the Scott Coast in the southern Ross Sea during a cooling period also at approximately 2000 BP. Our results suggest that the new colony at Cape Adare continued to grow, expanding to a large upper terrace above Ridley Beach, until it exceeded approximately 500 000 breeding pairs (a \u0027supercolony\u0027) by approximately 1200 BP. The high marine productivity associated with the Ross Sea polynya and continental shelf break supported this growth, but the colony collapsed to its present size for unknown reasons after approximately 1200 BP. Ridley Beach will probably be abandoned in the near future due to rising sea level in this region. We predict that penguins will retreat to higher elevations at Cape Adare and that the Scott Coast will be reoccupied by breeding penguins as fast ice continues to dissipate earlier each summer, restoring open-water access to beaches there.", "east": 170.19305556, "geometry": ["POINT(175.09652778 -65.65384722)"], "keywords": "Adelie Penguin; Antarctica; Biota; Cape Adare; East Antarctica; Population Movement; Pygoscelis Adeliae; Radiocarbon; Ross Sea; Sea Level Rise; Stable Isotopes", "locations": "Antarctica; East Antarctica; Ross Sea; Cape Adare", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "McKenzie, Ashley; Patterson, William; Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -71.30769444, "title": "The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "uid": "601327", "west": -180.0}, {"awards": "1043623 Miller, Scott", "bounds_geometry": ["POLYGON((117.5 -47,120.35 -47,123.2 -47,126.05 -47,128.9 -47,131.75 -47,134.6 -47,137.45 -47,140.3 -47,143.15 -47,146 -47,146 -49.04,146 -51.08,146 -53.12,146 -55.16,146 -57.2,146 -59.24,146 -61.28,146 -63.32,146 -65.36,146 -67.4,143.15 -67.4,140.3 -67.4,137.45 -67.4,134.6 -67.4,131.75 -67.4,128.9 -67.4,126.05 -67.4,123.2 -67.4,120.35 -67.4,117.5 -67.4,117.5 -65.36,117.5 -63.32,117.5 -61.28,117.5 -59.24,117.5 -57.2,117.5 -55.16,117.5 -53.12,117.5 -51.08,117.5 -49.04,117.5 -47))"], "date_created": "Fri, 01 May 2020 00:00:00 GMT", "description": "This dataset contains meteorological and air-sea flux data (momentum, heat, and CO2 fluxes; CO2 gas transfer velocity) collected during the the Nathaniel B. Palmer expedition NBP1402 conducted in 2014. The files are of XLS format.", "east": 146.0, "geometry": ["POINT(131.75 -57.2)"], "keywords": "Air-Sea Flux; Air Temperature; Antarctica; Atmosphere; CO2; CO2 Concentrations; East Antarctica; Flux; Meteorology; NBP1402; Oceans; Relative Humidity; Salinity; Totten Glacier; Water Measurements; Water Temperature; Weather Station Data; Wind Direction; Wind Speed", "locations": "Totten Glacier; East Antarctica; Antarctica", "north": -47.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "persons": "Miller, Scott; Butterworth, Brian", "project_titles": "Air-Sea Fluxes of Momentum, Heat, and Carbon Dioxide at High Wind Speeds in the Southern Ocean", "projects": [{"proj_uid": "p0010137", "repository": "USAP-DC", "title": "Air-Sea Fluxes of Momentum, Heat, and Carbon Dioxide at High Wind Speeds in the Southern Ocean"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.4, "title": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1402", "uid": "601308", "west": 117.5}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": ["POINT(62.99 -67.13)"], "date_created": "Fri, 01 May 2020 00:00:00 GMT", "description": "This data set was acquired with a Jumbo Piston Core Sediment Sampler during R/V Nathaniel B. Palmer expedition NBP0101 conducted in 2001. This data file is of Microsoft Excel format and includes Quantitative Diatom Assemblage data; counts completed on randomly settled slides (Scherer, R.P., 1994. A new method for the determination of absolute abundance of diatoms and other silt-sized sedimentary particles. Journal of Paleolimnology, 12 (1), 171-178, doi:10.1007/BF00678093). These counts were completed at closely spaced intervals in NBP0101 JPC41, a jumbo piston core from Iceberg Alley, Mac.Robertson Shelf, East Antarctica", "east": 62.99, "geometry": ["POINT(62.99 -67.13)"], "keywords": "Antarctica; Biota; Diatom; East Antarctica; Mac. Robertson Shelf; Marine Geoscience; Microscope; NBP0101; Paleoclimate; Piston Corer; R/v Nathaniel B. Palmer; Sediment Core; Species Abundance", "locations": "Mac. Robertson Shelf; Mac. Robertson Shelf; Antarctica; East Antarctica", "north": -67.13, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Leventer, Amy", "project_titles": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "projects": [{"proj_uid": "p0000609", "repository": "USAP-DC", "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.13, "title": "Quantitative Diatom Assemblage Data from Iceberg Alley, Mac. Robertson Shelf, East Antarctica acquired during expedition NBP0101", "uid": "601307", "west": 62.99}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((118 -65.5,118.3 -65.5,118.6 -65.5,118.9 -65.5,119.2 -65.5,119.5 -65.5,119.8 -65.5,120.1 -65.5,120.4 -65.5,120.7 -65.5,121 -65.5,121 -65.65,121 -65.8,121 -65.95,121 -66.1,121 -66.25,121 -66.4,121 -66.55,121 -66.7,121 -66.85,121 -67,120.7 -67,120.4 -67,120.1 -67,119.8 -67,119.5 -67,119.2 -67,118.9 -67,118.6 -67,118.3 -67,118 -67,118 -66.85,118 -66.7,118 -66.55,118 -66.4,118 -66.25,118 -66.1,118 -65.95,118 -65.8,118 -65.65,118 -65.5))"], "date_created": "Fri, 01 May 2020 00:00:00 GMT", "description": "This Biology Species Abundance data set was acquired with a ship-based Camera during Nathaniel B. Palmer expedition NBP1001 conducted in 2010 (Chief Scientist: Dr. Eugene Domack; Investigator: Dr. Craig Smith). The data file is in XLS format and includes Biology Species Abundance Biology data that has not been processed. The data was acquired as part of the project called Collaborative Research in IPY: Abrupt Environmental Change in the LARsen Ice Shelf System, Antarctica (LARISSA).", "east": 121.0, "geometry": ["POINT(119.5 -66.25)"], "keywords": "Antarctica; Benthic Images; Camera; East Antarctica; Marine Geoscience; NBP1402; Photo/video; Photo/Video; R/v Nathaniel B. Palmer; Sabrina Coast; Totten Glacier; Video Data; Yoyo Camera", "locations": "Sabrina Coast; Totten Glacier; East Antarctica; Antarctica", "north": -65.5, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy; Post, Alexandra; Blankenship, Donald D.; Domack, Eugene Walter; Gulick, Sean; Huber, Bruce; Orsi, Alejandro; Shevenell, Amelia", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Near-bottom Videos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402", "uid": "601312", "west": 118.0}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((118 -65.5,118.3 -65.5,118.6 -65.5,118.9 -65.5,119.2 -65.5,119.5 -65.5,119.8 -65.5,120.1 -65.5,120.4 -65.5,120.7 -65.5,121 -65.5,121 -65.65,121 -65.8,121 -65.95,121 -66.1,121 -66.25,121 -66.4,121 -66.55,121 -66.7,121 -66.85,121 -67,120.7 -67,120.4 -67,120.1 -67,119.8 -67,119.5 -67,119.2 -67,118.9 -67,118.6 -67,118.3 -67,118 -67,118 -66.85,118 -66.7,118 -66.55,118 -66.4,118 -66.25,118 -66.1,118 -65.95,118 -65.8,118 -65.65,118 -65.5))"], "date_created": "Fri, 01 May 2020 00:00:00 GMT", "description": "This data set was acquired with a Nikon D80 Digital Camera on a towed Yoyo camera system during R/V Nathaniel B. Palmer expedition NBP1402 conducted in 2014. 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Palmer; Totten Glacier; Yoyo Camera", "locations": "Totten Glacier; Antarctica; East Antarctica", "north": -65.5, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy; Post, Alexandra; Domack, Eugene Walter; Gulick, Sean; Huber, Bruce; Orsi, Alejandro; Shevenell, Amelia", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Bottom photos from the Southern Ocean acquired during R/V Nathaniel B. Palmer expedition NBP1402 ", "uid": "601310", "west": 118.0}, {"awards": "9911617 Blankenship, Donald; 9978236 Bell, Robin", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Processed IcePenetrating Radar Altimeter Shot Data (version 2) acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was acquired with a IcePenetrating Radar Altimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of SEGY format and include Reflection Radar shot data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Lake Vostok; Navigation; Radar; SOAR; Subglacial Lakes", "locations": "Antarctica; East Antarctica; Lake Vostok", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}, {"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey airborne radar data", "uid": "601300", "west": 101.5}, {"awards": "9978236 Bell, Robin; 9911617 Blankenship, Donald", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Bedrock Elevation Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Michael Studinger). These data files are of ASCII format and include Bedrock Elevation data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "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", "locations": "Antarctica; East Antarctica; Lake Vostok", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}, {"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey bed elevation data", "uid": "601299", "west": 101.5}, {"awards": "9978236 Bell, Robin; 9911617 Blankenship, Donald", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Surface Elevation Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Michael Studinger). These data files are of ASCII format and include Surface Elevation data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "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", "locations": "Antarctica; East Antarctica; Lake Vostok", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}, {"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey surface elevation data", "uid": "601298", "west": 101.5}, {"awards": "9911617 Blankenship, Donald; 9978236 Bell, Robin", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Processed IcePenetrating Radar Altimeter Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was acquired with a IcePenetrating Radar Altimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of ASCII format and include Ice LayerThickness data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "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", "locations": "East Antarctica; Lake Vostok; Antarctica", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}, {"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey ice thickness data", "uid": "601297", "west": 101.5}, {"awards": "9911617 Blankenship, Donald; 9978236 Bell, Robin", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Processed Magnetometer Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000)\r\nThis data set was acquired with a Magnetometer during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Chief Scientist: Dr. Robin Bell; Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of ASCII format and include IGRF Anomaly Magnetic data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "keywords": "Airborne Magnetic; Airplane; Antarctica; East Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Lake Vostok; Magnetic; Magnetic Anomaly; Magnetometer; Potential Field; SOAR; Solid Earth", "locations": "East Antarctica; Antarctica; Lake Vostok", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}, {"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok survey magnetic anomaly data", "uid": "601296", "west": 101.5}, {"awards": "9911617 Blankenship, Donald; 9978236 Bell, Robin", "bounds_geometry": ["POLYGON((101.5 -75.5,102.15 -75.5,102.8 -75.5,103.45 -75.5,104.1 -75.5,104.75 -75.5,105.4 -75.5,106.05 -75.5,106.7 -75.5,107.35 -75.5,108 -75.5,108 -75.85,108 -76.2,108 -76.55,108 -76.9,108 -77.25,108 -77.6,108 -77.95,108 -78.3,108 -78.65,108 -79,107.35 -79,106.7 -79,106.05 -79,105.4 -79,104.75 -79,104.1 -79,103.45 -79,102.8 -79,102.15 -79,101.5 -79,101.5 -78.65,101.5 -78.3,101.5 -77.95,101.5 -77.6,101.5 -77.25,101.5 -76.9,101.5 -76.55,101.5 -76.2,101.5 -75.85,101.5 -75.5))"], "date_created": "Tue, 28 Apr 2020 00:00:00 GMT", "description": "Processed Gravimeter Data acquired during the SOAR Twin Otter expedition SOAR-LVS (2000). This data set was acquired with a Gravimeter during SOAR Twin Otter expedition SOAR-LVS conducted in 2000 (Investigator(s): Dr. Robin Bell and Dr. Michael Studinger). These data files are of ASCII format and include Free Air Anomaly Gravity data and were processed after data collection. Data were acquired as part of the project(s): SOAR-Lake Vostok Survey (LVS) and Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work.", "east": 108.0, "geometry": ["POINT(104.75 -77.25)"], "keywords": "Airborne Gravity; Airplane; Antarctica; East Antarctica; Free Air Gravity; Glaciers/ice Sheet; Glaciers/Ice Sheet; Gravimeter; Gravity; Lake Vostok; Potential Field; Solid Earth", "locations": "Lake Vostok; East Antarctica; Antarctica", "north": -75.5, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Studinger, Michael S.; Bell, Robin", "project_titles": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR); Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n", "projects": [{"proj_uid": "p0000125", "repository": "USAP-DC", "title": "Continuation of Activities for the Support Office for Aerogeophysical Research (SOAR)"}, {"proj_uid": "p0010097", "repository": "USAP-DC", "title": "Understanding the Boundary Conditions of the Lake Vostok Environment: A Site Survey for Future Work\r\n"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "SOAR-Lake Vostok Survey Gravity data", "uid": "601295", "west": 101.5}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are jpeg images of Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "AGAP; Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar; Radar Echo Sounder", "locations": "East Antarctica; Antarctica; Gamburtsev Mountains", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin; Studinger, Michael S.", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Data (jpeg images) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT ", "uid": "601286", "west": 65.0}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of Netcdf format and include Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar Echo Sounder", "locations": "East Antarctica; Antarctica; Gamburtsev Mountains", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin; Studinger, Michael S.", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Data (Netcdf format) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT ", "uid": "601285", "west": 65.0}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of MATLAB format and include Reflection Radar data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar; Radar Echo Sounder", "locations": "Gamburtsev Mountains; East Antarctica; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin; Studinger, Michael S.", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Data (Matlab format) from the Gamburtsev Mountains in Antarctica acquired during GAMBIT ", "uid": "601284", "west": 65.0}, {"awards": "0632292 Bell, Robin", "bounds_geometry": ["POLYGON((65 -77.5,67.4 -77.5,69.8 -77.5,72.2 -77.5,74.6 -77.5,77 -77.5,79.4 -77.5,81.8 -77.5,84.2 -77.5,86.6 -77.5,89 -77.5,89 -78.25,89 -79,89 -79.75,89 -80.5,89 -81.25,89 -82,89 -82.75,89 -83.5,89 -84.25,89 -85,86.6 -85,84.2 -85,81.8 -85,79.4 -85,77 -85,74.6 -85,72.2 -85,69.8 -85,67.4 -85,65 -85,65 -84.25,65 -83.5,65 -82.75,65 -82,65 -81.25,65 -80.5,65 -79.75,65 -79,65 -78.25,65 -77.5))"], "date_created": "Mon, 20 Apr 2020 00:00:00 GMT", "description": "This data set was acquired with a Ice Penetrating Radar Altimeter during GAMBIT Twin Otter expedition AGAP_GAMBIT conducted in 2008 (Chief Scientist: Dr. Robin Bell). These data files are of SEGY format and include Reflection Radar shot data and were processed after data collection. Data were acquired as part of the project(s): AGAP: Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008 and Antarctica\u0027s Gamburtsev Province Project (AGAP).", "east": 89.0, "geometry": ["POINT(77 -81.25)"], "keywords": "Aerogeophysics; AGAP; Airborne Radar; Airplane; Antarctica; East Antarctica; Gamburtsev Mountains; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Radar; Radar Echo Sounder", "locations": "Antarctica; East Antarctica; Gamburtsev Mountains", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Bell, Robin", "project_titles": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets", "projects": [{"proj_uid": "p0000114", "repository": "USAP-DC", "title": "Collaborative Research: IPY: GAMBIT: Gamburtsev Aerogeophysical Mapping of Bedrock and Ice Targets"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Processed Ice Penetrating Radar Altimeter Shot Data (SEGY, version 1) from the Gamburtsev Mountains in Antarctica acquired during the GAMBIT Twin Otter expedition AGAP_GAMBIT (2008)", "uid": "601283", "west": 65.0}, {"awards": "1643901 Zhang, Weifeng", "bounds_geometry": ["POLYGON((55 -62,65 -62,75 -62,85 -62,95 -62,105 -62,115 -62,125 -62,135 -62,145 -62,155 -62,155 -62.8,155 -63.6,155 -64.4,155 -65.2,155 -66,155 -66.8,155 -67.6,155 -68.4,155 -69.2,155 -70,145 -70,135 -70,125 -70,115 -70,105 -70,95 -70,85 -70,75 -70,65 -70,55 -70,55 -69.2,55 -68.4,55 -67.6,55 -66.8,55 -66,55 -65.2,55 -64.4,55 -63.6,55 -62.8,55 -62))"], "date_created": "Tue, 10 Sep 2019 00:00:00 GMT", "description": "The emperor penguin, an iconic species threatened by projected sea-ice loss in Antarctica, has long been considered to forage at the fast ice edge, presumably relying on large/yearly-persistent polynyas as their main foraging habitat during the breeding season. Using newly developed fine-scale sea-icescape data and historical penguin tracking data, this study for the first time suggests the importance of less-recognized small openings, including cracks, flaw leads and ephemeral short-term polynyas, as foraging habitats for emperor penguins. The tracking data retrieved from 47 emperor penguins in two different colonies in East Antarctica suggest that those penguins spent 23% of their time in ephemeral polynyas and did not use the large/yearly-persistent, well-studied polynyas, even they occur much more regularly with predictable locations. These findings challenge our previous understanding of emperor penguin breeding habitats, highlighting the need for incorporating fine-scale seascape features when assessing the population persistence in a rapidly changing polar environment.", "east": 155.0, "geometry": ["POINT(105 -66)"], "keywords": "Animal Behavior Observation; Antarctica; Biota; East Antarctica; GPS; Oceans; Penguin; Southern Ocean", "locations": "Antarctica; Southern Ocean; East Antarctica", "north": -62.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Labrousse, Sara; Fraser, Alexander; Tamura, Takeshi; Pinaud, David; Wienecke, Barbara; Kirkwood, Roger; Ropert-Coudert, Yan; Resinger, Ryan; Jonsen, Ian; Porter-Smith, Rick; Barbraud, Christophe; Bost, Charles-Andr\u00e9; Ji, Rubao; Jenouvrier, Stephanie; Sumner, Michael", "project_titles": "Collaborative Research: Polynyas in Coastal Antarctica (PICA): Linking Physical Dynamics to Biological Variability", "projects": [{"proj_uid": "p0010044", "repository": "USAP-DC", "title": "Collaborative Research: Polynyas in Coastal Antarctica (PICA): Linking Physical Dynamics to Biological Variability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Dynamic fine-scale sea-icescape shapes adult emperor penguin foraging habitat in East Antarctica", "uid": "601209", "west": 55.0}, {"awards": "1443336 Osterberg, Erich", "bounds_geometry": ["POINT(-180 -90)"], "date_created": "Thu, 29 Aug 2019 00:00:00 GMT", "description": "The South Pole Ice Core (SPICEcore) was drilled in 2014-2016 to provide a detailed multi-proxy archive of paleoclimate conditions in East Antarctica during the Holocene and late Pleistocene. Interpretation of these records requires an accurate depth-age relationship. Here, we present the SP19 timescale for the age of the ice of SPICEcore. SP19 is synchronized to the WD2014 chronology from the West Antarctic Ice Sheet Divide (WAIS Divide) ice core using stratigraphic matching of 251 volcanic events. These events indicate an age of 54,302 +/- 519 years BP (before the year 1950) at the bottom of SPICEcore. Annual layers identified in sodium and magnesium ions to 11,341 BP were used to interpolate between stratigraphic volcanic tie points, yielding an annually-resolved chronology through the Holocene. Estimated timescale uncertainty during the Holocene is less than 18 years relative to WD2014, with the exception of the interval between 1800 to 3100 BP when uncertainty estimates reach +/- 25 years due to widely spaced volcanic tie points. Prior to the Holocene, uncertainties remain within 124 years relative to WD2014. Results show an average Holocene accumulation rate of 7.4 cm/yr (water equivalent). The time variability of accumulation rate is consistent with expectations for steady-state ice flow through the modern spatial pattern of accumulation rate. Time variations in nitrate concentration, nitrate seasonal amplitude, and \u03b415N of N2 in turn are as expected for the accumulation-rate variations. The highly variable yet well-constrained Holocene accumulation history at the site can help improve scientific understanding of deposition-sensitive climate proxies such as \u03b415N of N2 and photolyzed chemical compounds.", "east": -180.0, "geometry": ["POINT(-180 -90)"], "keywords": "Antarctica; Calcium (ca); Chemistry:ice; Chemistry:Ice; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciochemistry; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Ice Core Records; Ice Core Stratigraphy; Nitrate; Nitrogen Isotopes; Paleoclimate; Snow/ice; Snow/Ice; South Pole; SPICEcore", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Winski, Dominic A.; Fudge, T. J.; Dunbar, Nelia; Buizert, Christo; Bay, Ryan; Souney, Joseph Jr.; Sigl, Michael; McConnell, Joseph; Fegyveresi, John; Cole-Dai, Jihong; Thundercloud, Zayta; Cox, Thomas S.; Kreutz, Karl; Epifanio, Jenna; Ortman, Nikolas; Brook, Edward J.; Beaudette, Ross; Sowers, Todd A.; Steig, Eric J.; Morris, Valerie; Kahle, Emma; Ferris, David G.; Aydin, Murat; Nicewonger, Melinda R.; Casey, Kimberly A.; Alley, Richard; Waddington, Edwin D.; Osterberg, Erich; Severinghaus, Jeffrey P.; Jones, Tyler R.; Iverson, Nels", "project_titles": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements", "projects": [{"proj_uid": "p0010051", "repository": "USAP-DC", "title": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "The South Pole Ice Core (SPICEcore) chronology and supporting data", "uid": "601206", "west": -180.0}, {"awards": "9909367 Leventer, Amy", "bounds_geometry": ["POLYGON((57 -66,57.3 -66,57.6 -66,57.9 -66,58.2 -66,58.5 -66,58.8 -66,59.1 -66,59.4 -66,59.7 -66,60 -66,60 -66.1,60 -66.2,60 -66.3,60 -66.4,60 -66.5,60 -66.6,60 -66.7,60 -66.8,60 -66.9,60 -67,59.7 -67,59.4 -67,59.1 -67,58.8 -67,58.5 -67,58.2 -67,57.9 -67,57.6 -67,57.3 -67,57 -67,57 -66.9,57 -66.8,57 -66.7,57 -66.6,57 -66.5,57 -66.4,57 -66.3,57 -66.2,57 -66.1,57 -66))"], "date_created": "Thu, 25 Apr 2019 00:00:00 GMT", "description": "This data set describes diatom assemblages and abundances from two sediment cores retrieved from Edward VIII Gulf. The assemblages are used to reconstruct paleoceanographic conditions throughout the Holocene.", "east": 60.0, "geometry": ["POINT(58.5 -66.5)"], "keywords": "Antarctica; Biota; Diatom; East Antarctica; Microscopy; NBP0101; Oceans; Paleoceanography; Paleoclimate; R/v Nathaniel B. Palmer; Sediment Corer", "locations": "East Antarctica; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy", "project_titles": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "projects": [{"proj_uid": "p0000609", "repository": "USAP-DC", "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica", "uid": "601177", "west": 57.0}, {"awards": "1142002 Kaplan, Michael", "bounds_geometry": ["POLYGON((-58 -63.7,-57.95 -63.7,-57.9 -63.7,-57.85 -63.7,-57.8 -63.7,-57.75 -63.7,-57.7 -63.7,-57.65 -63.7,-57.6 -63.7,-57.55 -63.7,-57.5 -63.7,-57.5 -63.73,-57.5 -63.76,-57.5 -63.79,-57.5 -63.82,-57.5 -63.85,-57.5 -63.88,-57.5 -63.91,-57.5 -63.94,-57.5 -63.97,-57.5 -64,-57.55 -64,-57.6 -64,-57.65 -64,-57.7 -64,-57.75 -64,-57.8 -64,-57.85 -64,-57.9 -64,-57.95 -64,-58 -64,-58 -63.97,-58 -63.94,-58 -63.91,-58 -63.88,-58 -63.85,-58 -63.82,-58 -63.79,-58 -63.76,-58 -63.73,-58 -63.7))"], "date_created": "Sat, 16 Sep 2017 00:00:00 GMT", "description": "These are data sets obtained with the supported award. The ages concern the histories of glaciers, ice sheets, and general cryospheric and climatic activities of the northern Antarctic Peninsula and surrounding area.They cover periods from prior to the last global glacial maximum (stage 3 and older?) as well as since deglaciation.", "east": -57.5, "geometry": ["POINT(-57.75 -63.85)"], "keywords": "Antarctica; Antarctic Peninsula; Glaciers/ice Sheet; Glaciers/Ice Sheet; GPS; James Ross Island; Sample/collection Description; Sample/Collection Description; Solid Earth", "locations": "Antarctica; Antarctic Peninsula; James Ross Island", "north": -63.7, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Kaplan, Michael", "project_titles": "Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula", "projects": [{"proj_uid": "p0000337", "repository": "USAP-DC", "title": "Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "10Be and 14C data from northern Antarctic Peninsula", "uid": "601051", "west": -58.0}, {"awards": "1142085 Alley, Richard", "bounds_geometry": ["POLYGON((0 -75,5.489 -75,10.978 -75,16.467 -75,21.956 -75,27.445 -75,32.934 -75,38.423 -75,43.912 -75,49.401 -75,54.89 -75,54.89 -75.763,54.89 -76.526,54.89 -77.289,54.89 -78.052,54.89 -78.815,54.89 -79.578,54.89 -80.341,54.89 -81.104,54.89 -81.867,54.89 -82.63,49.401 -82.63,43.912 -82.63,38.423 -82.63,32.934 -82.63,27.445 -82.63,21.956 -82.63,16.467 -82.63,10.978 -82.63,5.489 -82.63,0 -82.63,0 -81.867,0 -81.104,0 -80.341,0 -79.578,0 -78.815,0 -78.052,0 -77.289,0 -76.526,0 -75.763,0 -75))"], "date_created": "Tue, 05 Sep 2017 00:00:00 GMT", "description": "", "east": 54.89, "geometry": ["POINT(27.445 -78.815)"], "keywords": "Antarctica; Borehole Logging; Dronning Maud Land; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Physical Properties; Snow; Temperature", "locations": "Dronning Maud Land; Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Muto, Atsu", "project_titles": "Revealing Late Holocence Climate Variability in Antarctica from Borehole Paleothermometry", "projects": [{"proj_uid": "p0000440", "repository": "USAP-DC", "title": "Revealing Late Holocence Climate Variability in Antarctica from Borehole Paleothermometry"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.63, "title": "Firn-temperature time series in Dronning Maud Land, East Antarctica", "uid": "601050", "west": 0.0}, {"awards": "1430550 Domack, Eugene", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"], "date_created": "Fri, 18 Aug 2017 00:00:00 GMT", "description": "Bulk sediment carbon and nitrogen data data for Paleocene sediments collected on Totten continental shelf, East Antarctica. ", "east": 121.0, "geometry": ["POINT(120.5 -68)"], "keywords": "Antarctica; Carbon; Chemistry:sediment; Chemistry:Sediment; Geochemistry; Marine Sediments; NBP1402; Nitrogen; Oceans; Sabrina Coast; Sediment Core; Southern Ocean; Totten Glacier", "locations": "Southern Ocean; Totten Glacier; Sabrina Coast; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Smith, Catherine; Shevenell, Amelia; Domack, Eugene Walter", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "NBP14-02 JPC-55 Bulk Sediment Carbon and Nitrogen data", "uid": "601044", "west": 120.0}, {"awards": "1430550 Domack, Eugene", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"], "date_created": "Fri, 18 Aug 2017 00:00:00 GMT", "description": "Pollen assemblage data for Paleocene to early to middle Eocene sediments collected on Totten continental shelf, East Antarctica. ", "east": 121.0, "geometry": ["POINT(120.5 -68)"], "keywords": "Antarctica; Biota; Marine Sediments; NBP1402; Oceans; Paleoclimate; Pollen; Sabrina Coast; Sediment Core; Southern Ocean; Totten Glacier", "locations": "Sabrina Coast; Southern Ocean; Totten Glacier; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Shevenell, Amelia; Smith, Catherine; Domack, Eugene Walter", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "NBP14-02 JPC-54 and JPC-55 Pollen Assemblage data", "uid": "601046", "west": 120.0}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.4,121 -66.8,121 -67.2,121 -67.6,121 -68,121 -68.4,121 -68.8,121 -69.2,121 -69.6,121 -70,120.9 -70,120.8 -70,120.7 -70,120.6 -70,120.5 -70,120.4 -70,120.3 -70,120.2 -70,120.1 -70,120 -70,120 -69.6,120 -69.2,120 -68.8,120 -68.4,120 -68,120 -67.6,120 -67.2,120 -66.8,120 -66.4,120 -66))"], "date_created": "Fri, 18 Aug 2017 00:00:00 GMT", "description": "Foraminifer assemblage data for Paleocene sediments collected on Totten continental shelf, East Antarctica.", "east": 121.0, "geometry": ["POINT(120.5 -68)"], "keywords": "Antarctica; Biota; Continental Margin; Foraminifera; NBP1402; Oceans; Paleoclimate; Sabrina Coast; Sample/collection Description; Sample/Collection Description; Southern Ocean; Totten Glacier", "locations": "Totten Glacier; Sabrina Coast; Southern Ocean; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Shevenell, Amelia; Leventer, Amy", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "NBP14-02 JPC-55 foraminifer assemblage data", "uid": "601042", "west": 120.0}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": ["POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))"], "date_created": "Thu, 06 Apr 2017 00:00:00 GMT", "description": "Stretching ~3,500 km across Antarctica, with peak elevations up to 4,500 m, the Transantarctic Mountains (TAMs) are the largest non-compressional mountain range on Earth and represent a tectonic boundary between the East Antarctica (EA) craton and the West Antarctic Rift System. The origin and uplift mechanism associated with the TAMs is controversial, and multiple models have been proposed. Seismic investigations of the TAMs\u0027 subsurface structure can provide key constraints to help evaluate these models, but previous studies have been primarily focused only on the central TAMs near Ross Island. Using data from the new 15-station Transantarctic Mountain Northern Network as well as data from several smaller networks, this study investigates the upper mantle velocity structure beneath a previously unexplored portion of the northern TAMs through regional body wave tomography. Relative travel-times were calculated for 11,182 P-wave and 8,285 S-wave arrivals from 790 and 581 Mw \u2265 5.5 events, respectively, using multi-channel cross correlation, and these data were then inverted for models of the upper mantle seismic structure. Resulting P- and S-wave tomography images reveal two focused low velocity anomalies beneath Ross Island (RI; \u03b4VP \u2248 -2.0%; \u03b4VS \u2248 -1.5% to -4.0%) and Terra Nova Bay (TNB; \u03b4VP \u2248 -1.5% to -2.0%; \u03b4VS \u2248 -1.0% to -4.0%) that extend to depths of ~200 and ~150 km, respectively. The RI and TNB slow anomalies also extend ~50-100 km laterally beneath the TAMs front and sharply abut fast velocities beneath the EA craton (\u03b4VP \u2248 0.5% to 2%; \u03b4VS \u2248 1.5% to 4.0%). A low velocity region (\u03b4VP \u2248 -1.5%), centered at ~150 km depth beneath the Terror Rift (TR) and primarily constrained within the Victoria Land Basin, connects the RI and TNB anomalies. The focused low velocities are interpreted as regions of partial melt and buoyancy-driven upwelling, connected by a broad region of slow (presumably warm) upper mantle associated with Cenozoic extension along the TR. Dynamic topography estimates based on the imaged S-wave velocity perturbations are consistent with observed surface topography in the central and northern TAMs, thereby providing support for uplift models that advocate for thermal loading and a flexural origin for the mountain range.", "east": 165.120012, "geometry": ["POINT(159.223506 -74.6349495)"], "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -73.032547, "nsf_funding_programs": null, "persons": "Hansen, Samantha", "project_titles": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "projects": [{"proj_uid": "p0000300", "repository": "USAP-DC", "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.237352, "title": "Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography", "uid": "601017", "west": 153.327}, {"awards": "1043750 Chen, Jianli", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to improve the estimate of long-term and inter-annual variability of Antarctic ice sheet mass balance at continental, regional, and catchment scales, using satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) and other geodetic measurements. The work will improve the quantification of long-term mass change rates over Antarctica using GRACE gravity data with a longer record and newer generation(s) of products and will develop advanced numerical forward modeling techniques that can accurately correct leakage effects associated with GRACE data processing, and significantly improve spatial resolution of GRACE mass rate estimates over Antarctica. The work will also contribute to a better understanding of crustal uplift rates due to postglacial rebound (PGR) and present day ice load change over Antarctica via PGR models, GPS measurements, and combined analysis of GRACE and ICESat elevation changes. Inter-annual variations of ice mass over Antarctica will be investigated at continental and catchment scales and connections to regional climate change will be studied. The major deliverables from this study will be improved assessments of ice mass balance for the entire Antarctic ice sheet and potential contribution to global mean sea level rise. The work will also provide estimates of regional ice mass change rates over Antarctica, with a focus along the coast in the Amundsen Sea Embayment, the Peninsula in West Antarctica, and in Wilkes Land and Victoria Land in East Antarctica. Estimates of inter-annual ice mass change over Antarctica at various spatial scales, and assessments of uncertainty of GRACE ice rate estimates and PGR models errors over Antarctica will also be made. The intellectual merits of the proposed investigation include 1) providing improved assessments of Antarctic ice mass balance at different temporal and spatial scales with unprecedented accuracy, an important contribution to broad areas of polar science research; 2) combining high accuracy GPS vertical uplift measurements and PGR models to better quantify long-term crust uplift effects that are not distinguishable from ice mass changes by GRACE; and 3) unifying the work of several investigations at the forefront of quantifying ice sheet and glacier mass balance and crustal uplift based on a variety of modern space geodetic observations. The broader impacts include the fact that the project will actively involve student participation and training, through the support of two graduate students. In addition the project will contribute to general education and public outreach (E/PO) activities and the results from this investigation will help inspire future geoscientists and promote public awareness of significant manifestations of climate change.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; GRACE; Potential Field; Satellite Data", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Chen, Jianli", "project_titles": "Collaborative Research: Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements", "projects": [{"proj_uid": "p0000415", "repository": "USAP-DC", "title": "Collaborative Research: Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Long-Term and Interannual Variability of Antarctic Ice Sheet Mass Balance From Satellite Gravimetry and Other Geodetic Measurements", "uid": "600159", "west": -180.0}, {"awards": "1142156 Marschall, Horst", "bounds_geometry": ["POLYGON((-6.44 -71.93,-5.378 -71.93,-4.316 -71.93,-3.254 -71.93,-2.192 -71.93,-1.13 -71.93,-0.068 -71.93,0.994 -71.93,2.056 -71.93,3.118 -71.93,4.18 -71.93,4.18 -71.998,4.18 -72.066,4.18 -72.134,4.18 -72.202,4.18 -72.27,4.18 -72.338,4.18 -72.406,4.18 -72.474,4.18 -72.542,4.18 -72.61,3.118 -72.61,2.056 -72.61,0.994 -72.61,-0.068 -72.61,-1.13 -72.61,-2.192 -72.61,-3.254 -72.61,-4.316 -72.61,-5.378 -72.61,-6.44 -72.61,-6.44 -72.542,-6.44 -72.474,-6.44 -72.406,-6.44 -72.338,-6.44 -72.27,-6.44 -72.202,-6.44 -72.134,-6.44 -72.066,-6.44 -71.998,-6.44 -71.93))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "Geochemical studies of single mineral grains in rocks can be probed to reconstruct the history of our planet. The mineral zircon (ZrSiO4) is of unique importance in that respect because of its reliability as a geologic clock due to its strong persistence against weathering, transport and changes in temperature and pressure. Uranium-Lead (U-Pb) dating of zircon grains is, perhaps, the most frequently employed method of extracting time information on geologic processes that shaped the continental crust, and has been used to constrain the evolution of continents and mountain belts through time. In addition, the isotopic composition of the element Hafnium (Hf) in zircon is used to date when the continental crust was generated by extraction of magma from the underlying mantle. Melting of rocks in the mantle and deep in the continental crust are key processes in the evolution of the continents, and they are recorded in the Hf isotopic signatures of zircon. Although the analytical procedures for U-Pb dating and Hf isotope analyses of zircon are robust now, our understanding of zircon growth and its exchange of elements and isotopes with its surrounding rock or magma are still underdeveloped. The focus of the proposed study, therefore, is to unravel the evolution of zircon Hf isotopes in rocks that were formed deep in the Earth\u0027s crust, and more specifically, to apply these isotopic methods to rocks collected in Dronning Maud Land (DML), East Antarctica.\n\nDronning Maud Land (DML) occupied a central location during the formation of supercontinents - large landmasses made up of all the continents that exist today - more than 500 million years ago. It is currently thought that supercontinents were formed and dismembered five or six times throughout Earth\u0027s history. The area of DML is key for understanding the formation history of the last two supercontinents. The boundaries of continents that were merged to form those supercontinents are most likely hidden in DML. In this study, the isotopic composition of zircon grains recovered from DML rocks will be employed to identify these boundaries across an extensive section through the area. The rock samples were collected by the investigator during a two-month expedition to Antarctica in the austral summer of 2007-2008. The results of dating and isotope analyses of zircon of the different DML crustal domains will deliver significant insight into the regional geology of East Antarctica and its previous northern extension into Africa. This has significance for the reconstruction of the supercontinents and defining the continental boundaries in DML.\n", "east": 4.18, "geometry": ["POINT(-1.13 -72.27)"], "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Dronning Maud Land; Geochemistry; Geochronology; Solid Earth", "locations": "Dronning Maud Land; Antarctica", "north": -71.93, "nsf_funding_programs": null, "persons": "Marschall, Horst", "project_titles": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica", "projects": [{"proj_uid": "p0000448", "repository": "USAP-DC", "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antacrtica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.61, "title": "Zircon Hf Isotopes and the Continental Evolution of Dronning Maud Land, East Antarctica", "uid": "600135", "west": -6.44}, {"awards": "0636953 Saltzman, Eric", "bounds_geometry": ["POINT(158.43 -77.48)"], "date_created": "Wed, 10 Sep 2014 00:00:00 GMT", "description": "This data set includes methyl chloride (CH\u003csub\u003e3\u003c/sub\u003eCI) measurements made on air extracted from 62 samples from the Taylor Dome M3C1 ice core in East Antarctica. CH\u003csub\u003e3\u003c/sub\u003eCI was measured in air from the Taylor Dome ice core to reconstruct an atmospheric record for the Holocene (11-0 kyr B.P.) and part of the last glacial period (50-30 kyr B.P.).", "east": 158.43, "geometry": ["POINT(158.43 -77.48)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "locations": "Antarctica; Taylor Dome", "north": -77.48, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Saltzman, Eric; Aydin, Murat", "project_titles": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores", "projects": [{"proj_uid": "p0000042", "repository": "USAP-DC", "title": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.48, "title": "Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core", "uid": "609600", "west": 158.43}, {"awards": "1354231 Kowalewski, Douglas", "bounds_geometry": ["POLYGON((-160 -70,-156 -70,-152 -70,-148 -70,-144 -70,-140 -70,-136 -70,-132 -70,-128 -70,-124 -70,-120 -70,-120 -71.5,-120 -73,-120 -74.5,-120 -76,-120 -77.5,-120 -79,-120 -80.5,-120 -82,-120 -83.5,-120 -85,-124 -85,-128 -85,-132 -85,-136 -85,-140 -85,-144 -85,-148 -85,-152 -85,-156 -85,-160 -85,-160 -83.5,-160 -82,-160 -80.5,-160 -79,-160 -77.5,-160 -76,-160 -74.5,-160 -73,-160 -71.5,-160 -70))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: Neogene sediment records recovered by ANDRILL suggest multiple events of open water conditions and elevated sea surface temperatures at times when terrestrial data from the McMurdo Dry Valleys indicate hyper arid, cold, desert conditions. Interpretation of the ANDRILL data suggests the West Antarctic Ice Sheet is highly sensitive to changes in Pliocene sea surface temperatures and this conclusion has been supported by recent Global Circulation Model results for the early to mid Pliocene. The PIs propose to model paleo-ice configurations and warm orbits associated with a WAIS collapse to assess potential climate change in East Antarctica. During such episodes of polar warmth they propose to answer: What is the limit of ablation along the East Antarctic Ice Sheet?; Are relict landforms in the Dry Valleys susceptible to modification from increase in maximum summertime temperatures?; and Is there sufficient increase in minimum wintertime temperatures to sustain a tundra environment in the Dry Valleys? Integration of depositional records and model outputs have the potential to test the performance of numerical models currently under development as part of ANDRILL; reconcile inconsistencies between marine and terrestrial paleoclimate records in high Southern Latitudes; and improve understanding of Antarctic climate and ice volume sensitivity to forcing for both the East Antarctic and West Antarctic Ice Sheets. Broader impacts: Results from this study have the potential to be used widely by the research community. Outreach to local elementary schools from other funded efforts will continue and be extended to homeschooled students. A Post Doc will be supported as part of this award.\n", "east": -120.0, "geometry": ["POINT(-140 -77.5)"], "keywords": "Antarctica; Atmosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Model Data; Paleoclimate; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -70.0, "nsf_funding_programs": null, "persons": "Kowalewski, Douglas", "project_titles": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "projects": [{"proj_uid": "p0000463", "repository": "USAP-DC", "title": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Validating contrasting terrestrial climate-sensitive Pliocene deposits through high resolution modeling of paleo-environments in the Transantarctic Mountains", "uid": "600140", "west": -160.0}, {"awards": "1043619 Hemming, Sidney", "bounds_geometry": ["POLYGON((-180 -63.997,-179.7982 -63.997,-179.5964 -63.997,-179.3946 -63.997,-179.1928 -63.997,-178.991 -63.997,-178.7892 -63.997,-178.5874 -63.997,-178.3856 -63.997,-178.1838 -63.997,-177.982 -63.997,-177.982 -66.3324,-177.982 -68.6678,-177.982 -71.0032,-177.982 -73.3386,-177.982 -75.674,-177.982 -78.0094,-177.982 -80.3448,-177.982 -82.6802,-177.982 -85.0156,-177.982 -87.351,-178.1838 -87.351,-178.3856 -87.351,-178.5874 -87.351,-178.7892 -87.351,-178.991 -87.351,-179.1928 -87.351,-179.3946 -87.351,-179.5964 -87.351,-179.7982 -87.351,180 -87.351,172.54273 -87.351,165.08546 -87.351,157.62819 -87.351,150.17092 -87.351,142.71365 -87.351,135.25638 -87.351,127.79911 -87.351,120.34184 -87.351,112.88457 -87.351,105.4273 -87.351,105.4273 -85.0156,105.4273 -82.6802,105.4273 -80.3448,105.4273 -78.0094,105.4273 -75.674,105.4273 -73.3386,105.4273 -71.0032,105.4273 -68.6678,105.4273 -66.3324,105.4273 -63.997,112.88457 -63.997,120.34184 -63.997,127.79911 -63.997,135.25638 -63.997,142.71365 -63.997,150.17092 -63.997,157.62819 -63.997,165.08546 -63.997,172.54273 -63.997,-180 -63.997))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: The PIs proposed a provenance study of glacial deposits in the Ross Embayment that will provide a broad scale geochronologic survey of detrital minerals in till to help characterize bedrock beneath the East Antarctic ice sheet and constrain Antarctica?s glacial history. This project capitalizes on previous investments in field sampling. Analytical tools applied to single mineral grains extracted from existing collections of glacial till will generate ?fingerprints? of East Antarctic outlet glaciers and West Antarctic till to refine paleo-ice flow models for the Ross Embayment during the last glacial maximum, older records from ANDRILL cores, and to assess IRD sources in the Southern Ocean. New provenance tracers will include a suite of geochronological methods that together provide greater insights into the orogenic and erosional history the region. This project will include U/Pb of detrital zircons, (U-Th)/He on a subset of the U/Pb dated zircons, as well as Ar-Ar of detrital hornblende, mica and feldspars.\nBroader Impacts: This research will train one M.S. student at IUPUI, a Ph.D. student at Columbia, and several undergraduates at both institutions. Graduate students involved in the project will be involved in mentoring undergraduate researchers. Incorporation of research discoveries will be brought into the classroom by providing concrete examples and exercises at the appropriate level. Licht and Columbia graduate student E. Pierce are developing outreach projects with local secondary school teachers to investigate the provenance of glacial materials in their local areas. The research will have broad applicability to many fields.", "east": 105.4273, "geometry": ["POINT(143.72265 -75.674)"], "keywords": "Antarctica; East Antarctica; Geochemistry; Ross Sea; Sample/collection Description; Sample/Collection Description; Solid Earth; Southern Ocean; West Antarctica", "locations": "Southern Ocean; Antarctica; West Antarctica; East Antarctica; Ross Sea", "north": -63.997, "nsf_funding_programs": null, "persons": "Hemming, Sidney R.", "project_titles": "Collaborative Research: East Antarctic outlet glacier contributions to the Ross Sea from chronology of detrital grains", "projects": [{"proj_uid": "p0000333", "repository": "USAP-DC", "title": "Collaborative Research: East Antarctic outlet glacier contributions to the Ross Sea from chronology of detrital grains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.351, "title": "East Antarctic outlet glacier contributions to the Ross Sea from chronology of detrital grains", "uid": "600124", "west": -177.982}, {"awards": "0944475 Kaplan, Michael", "bounds_geometry": ["POLYGON((-180 -84.1,-176.97 -84.1,-173.94 -84.1,-170.91 -84.1,-167.88 -84.1,-164.85 -84.1,-161.82 -84.1,-158.79 -84.1,-155.76 -84.1,-152.73 -84.1,-149.7 -84.1,-149.7 -84.43,-149.7 -84.76,-149.7 -85.09,-149.7 -85.42,-149.7 -85.75,-149.7 -86.08,-149.7 -86.41,-149.7 -86.74,-149.7 -87.07,-149.7 -87.4,-152.73 -87.4,-155.76 -87.4,-158.79 -87.4,-161.82 -87.4,-164.85 -87.4,-167.88 -87.4,-170.91 -87.4,-173.94 -87.4,-176.97 -87.4,180 -87.4,178.12 -87.4,176.24 -87.4,174.36 -87.4,172.48 -87.4,170.6 -87.4,168.72 -87.4,166.84 -87.4,164.96 -87.4,163.08 -87.4,161.2 -87.4,161.2 -87.07,161.2 -86.74,161.2 -86.41,161.2 -86.08,161.2 -85.75,161.2 -85.42,161.2 -85.09,161.2 -84.76,161.2 -84.43,161.2 -84.1,163.08 -84.1,164.96 -84.1,166.84 -84.1,168.72 -84.1,170.6 -84.1,172.48 -84.1,174.36 -84.1,176.24 -84.1,178.12 -84.1,-180 -84.1))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica\u0027s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed \u003c2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time.\nBroader Impact: The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.", "east": -149.7, "geometry": ["POINT(-174.25 -85.75)"], "keywords": "Antarctica; Cosmogenic Dating; Sample/collection Description; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -84.1, "nsf_funding_programs": null, "persons": "Kaplan, Michael", "project_titles": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "projects": [{"proj_uid": "p0000459", "repository": "USAP-DC", "title": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.4, "title": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "uid": "600115", "west": 161.2}, {"awards": "0944489 Williams, Trevor", "bounds_geometry": ["POLYGON((-55 -58,-33.2 -58,-11.4 -58,10.4 -58,32.2 -58,54 -58,75.8 -58,97.6 -58,119.4 -58,141.2 -58,163 -58,163 -60,163 -62,163 -64,163 -66,163 -68,163 -70,163 -72,163 -74,163 -76,163 -78,141.2 -78,119.4 -78,97.6 -78,75.8 -78,54 -78,32.2 -78,10.4 -78,-11.4 -78,-33.2 -78,-55 -78,-55 -76,-55 -74,-55 -72,-55 -70,-55 -68,-55 -66,-55 -64,-55 -62,-55 -60,-55 -58))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: The PIs propose to study the stability and dynamics of the East Antarctic ice sheet during the Pliocene in the area of the Wilkes and Aurora subglacial basins. Models indicate the ice sheet is most sensitive to warming in these low-lying areas. This study is important as there is very little direct evidence about which parts of the East Antarctic ice sheet became unstable under warm conditions. In a pilot study the PIs have shown that the isotopic geochemical signature of downcore ice-rafted debris (IRD) can be linked to continental source areas indicating which parts of the ice sheet reached the coast and calved IRD-bearing icebergs. Their initial results suggest rapid iceberg discharge from the Wilkes Land and Adelie Land coastal areas at times in the late Miocene and early Pliocene. In this study the PIs will analyze IRD from IODP sediment cores collected on the continental rise off East Antarctica. By analyzing 40Ar/39Ar ages of hornblende IRD grains, U-Pb ages of zircons, and Sm-Nd isotopes of the fine fraction of several IRD-rich layers for each core, they will be able to fingerprint continental source areas that indicate ice extent and dynamics on East Antarctica. The PIs will also carry out detailed studies across a few of these layers to characterize the anatomy of the ice-rafting event and better understand the mechanism of ice destabilization. Broader impacts: The data collected will be important for scientists in a broad variety of fields. The project will involve one undergraduate student and one summer intern at LDEO, and a graduate student at Imperial College London. The project will expose to cutting edge methodologies as well as an international research team. Data from the project will be deposited in the online databases (SedDB) and all results and methods will be made available to the scientific community through publications in peer-reviewed journals and attendance at international conferences\n", "east": 163.0, "geometry": ["POINT(54 -68)"], "keywords": "Geochronology; George V Land; IODP U1356; IODP U1361; Marine Sediments; ODP1165; Prydz Bay; Solid Earth; Southern Ocean; Wilkes Land", "locations": "George V Land; Southern Ocean; Wilkes Land; Prydz Bay", "north": -58.0, "nsf_funding_programs": null, "persons": "Williams, Trevor; Hemming, Sidney R.", "project_titles": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "projects": [{"proj_uid": "p0000353", "repository": "USAP-DC", "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "History of the East Antarctic Ice Sheet since the mid-Miocene: New Evidence from Provenance of Ice-rafted Debris", "uid": "600116", "west": -55.0}, {"awards": "0739681 Murray, Alison; 0739698 Doran, Peter", "bounds_geometry": ["POINT(161.931 -77.3885)"], "date_created": "Tue, 01 Jan 2013 00:00:00 GMT", "description": "Lake Vida is the largest lake of the McMurdo Dry Valleys, with an approximately 20 m ice cover overlaying a brine of unknown depth with at least 7 times seawater salinity and temperatures below -10 degrees C year-round. Samples of brine collected from ice above the main water body contain 1) the highest nitrous oxide levels of any natural water body on Earth, 2) unusual geochemistry including anomalously high ammonia and iron concentrations, 3) high microbial counts with an unusual proportion (99%) of ultramicrobacteria. The microbial community is unique even compared to other Dry Valley Lakes. The research proposes to enter, for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical and microbiological analyses. The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake\u0027s history. The research will be conducted by a multidisciplinary team that will uncover the biogeochemical processes associated with a non-photosynthetic microbial community isolated for a significant period of time. This research will address diversity, adaptive mechanisms and evolutionary processes in the context of the physical evolution of the environment of Lake Vida. Results will be widely disseminated through publications, presentations at national and international meetings, through the Subglacial Antarctic Lake Exploration (SALE) web site and the McMurdo LTER web site. The research will support three graduate students and three undergraduate research assistants. The results will be incorporated into a new undergraduate biogeosciences course at the University of Illinois at Chicago which has an extremely diverse student body, dominated by minorities.", "east": 161.931, "geometry": ["POINT(161.931 -77.3885)"], "keywords": "Antarctica; Biota; Carbon-14; Chemistry:fluid; Chemistry:Fluid; Chemistry:ice; Chemistry:Ice; Dry Valleys; Geochronology; Ice Core Records; Lake Vida; Microbiology", "locations": "Lake Vida; Antarctica; Dry Valleys", "north": -77.3885, "nsf_funding_programs": null, "persons": "Murray, Alison", "project_titles": "Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "projects": [{"proj_uid": "p0000485", "repository": "USAP-DC", "title": "Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.3885, "title": "Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica", "uid": "600080", "west": 161.931}, {"awards": "0538416 McConnell, Joseph", "bounds_geometry": ["POLYGON((-54.9 -73.7,-49.57 -73.7,-44.24 -73.7,-38.91 -73.7,-33.58 -73.7,-28.25 -73.7,-22.92 -73.7,-17.59 -73.7,-12.26 -73.7,-6.93 -73.7,-1.6 -73.7,-1.6 -74.61,-1.6 -75.52,-1.6 -76.43,-1.6 -77.34,-1.6 -78.25,-1.6 -79.16,-1.6 -80.07,-1.6 -80.98,-1.6 -81.89,-1.6 -82.8,-6.93 -82.8,-12.26 -82.8,-17.59 -82.8,-22.92 -82.8,-28.25 -82.8,-33.58 -82.8,-38.91 -82.8,-44.24 -82.8,-49.57 -82.8,-54.9 -82.8,-54.9 -81.89,-54.9 -80.98,-54.9 -80.07,-54.9 -79.16,-54.9 -78.25,-54.9 -77.34,-54.9 -76.43,-54.9 -75.52,-54.9 -74.61,-54.9 -73.7))"], "date_created": "Wed, 08 Aug 2012 00:00:00 GMT", "description": "This data set consists of sodium (Na) and magnesium (Mg) concentrations versus depth in seven ice cores that were obtained by the Norwegian-U.S. Scientific Traverse of East Antarctica during the International Polar Year (IPY) 2007-2009. Additional glaciochemical analyses and a final depth-age scale will be added as these data become available.\n\nData are available via FTP.", "east": -1.6, "geometry": ["POINT(-28.25 -78.25)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; East Antarctica; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records", "locations": "East Antarctica; Antarctica", "north": -73.7, "nsf_funding_programs": "Antarctic Glaciology", "persons": "McConnell, Joseph", "project_titles": "Collaborative Research: Norwegian-United States IPY Scientific Traverse: Climate Variability and Glaciology in East Antarctica", "projects": [{"proj_uid": "p0000095", "repository": "USAP-DC", "title": "Collaborative Research: Norwegian-United States IPY Scientific Traverse: Climate Variability and Glaciology in East Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.8, "title": "Ice Core Chemistry from the Norwegian-U.S. Scientific Traverse of East Antarctica, IPY 2007-2009", "uid": "609520", "west": -54.9}, {"awards": "0838722 Reiners, Peter", "bounds_geometry": ["POLYGON((61.9 -67.28,63.218 -67.28,64.536 -67.28,65.854 -67.28,67.172 -67.28,68.49 -67.28,69.808 -67.28,71.126 -67.28,72.444 -67.28,73.762 -67.28,75.08 -67.28,75.08 -67.922,75.08 -68.564,75.08 -69.206,75.08 -69.848,75.08 -70.49,75.08 -71.132,75.08 -71.774,75.08 -72.416,75.08 -73.058,75.08 -73.7,73.762 -73.7,72.444 -73.7,71.126 -73.7,69.808 -73.7,68.49 -73.7,67.172 -73.7,65.854 -73.7,64.536 -73.7,63.218 -73.7,61.9 -73.7,61.9 -73.058,61.9 -72.416,61.9 -71.774,61.9 -71.132,61.9 -70.49,61.9 -69.848,61.9 -69.206,61.9 -68.564,61.9 -67.922,61.9 -67.28))"], "date_created": "Sun, 01 Jan 2012 00:00:00 GMT", "description": "Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion.\n", "east": 75.08, "geometry": ["POINT(68.49 -70.49)"], "keywords": "Antarctica; Fission Track Thermochronology; Gamburtsev Mountains; Geochronology; Marine Sediments; NBP0101; ODP1166; ODP739; Prydz Bay; Solid Earth; Southern Ocean", "locations": "Prydz Bay; Southern Ocean; Gamburtsev Mountains; Antarctica", "north": -67.28, "nsf_funding_programs": null, "persons": "Gehrels, George; Reiners, Peter; Thomson, Stuart", "project_titles": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "projects": [{"proj_uid": "p0000506", "repository": "USAP-DC", "title": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -73.7, "title": "Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "uid": "600093", "west": 61.9}, {"awards": "0838914 Wannamaker, Philip", "bounds_geometry": ["POLYGON((141.01732 -82.13,144.910279 -82.13,148.803238 -82.13,152.696197 -82.13,156.589156 -82.13,160.482115 -82.13,164.375074 -82.13,168.268033 -82.13,172.160992 -82.13,176.053951 -82.13,179.94691 -82.13,179.94691 -82.351835,179.94691 -82.57367,179.94691 -82.795505,179.94691 -83.01734,179.94691 -83.239175,179.94691 -83.46101,179.94691 -83.682845,179.94691 -83.90468,179.94691 -84.126515,179.94691 -84.34835,176.053951 -84.34835,172.160992 -84.34835,168.268033 -84.34835,164.375074 -84.34835,160.482115 -84.34835,156.589156 -84.34835,152.696197 -84.34835,148.803238 -84.34835,144.910279 -84.34835,141.01732 -84.34835,141.01732 -84.126515,141.01732 -83.90468,141.01732 -83.682845,141.01732 -83.46101,141.01732 -83.239175,141.01732 -83.01734,141.01732 -82.795505,141.01732 -82.57367,141.01732 -82.351835,141.01732 -82.13))"], "date_created": "Sun, 01 Jan 2012 00:00:00 GMT", "description": "The investigators will examine competing hypotheses for the mechanism of extension and creation of the Transantarctic Mountains, and evolution of the thermal regimes of rifted West Antarctica and stable East Antarctica using magnetotelluric (MT) profiles. Surrounded almost entirely by ocean ridges, Antarctica is a special tectonic situation because of the need to make accommodation space for rifting in the Transantarctic region. In the MT method, temporal variations in the Earth\u0027s natural electromagnetic field are used as source fields to probe the electrical resistivity structure in the depth range of 1 to 200 km, or more. Geophysical methods, such as MT, are appropriate in Antarctica because of the predominance of thick ice cover over most of the Continent and the difficult operating environment. The proposed effort will consist of approximately 50 sites over a distance approaching 500 km with a 10 km average spacing, oriented normal to the Transantarctic Mountains (TAM), in the Beardmore glacier area. High quality MT soundings will be collected over thick ice sheets using a custom electrode preamp design, updated from previous Antarctic projects. Data acquisition will take place over two field seasons. The primary goals are three-fold: to establish the location of the deeper tectonic transition between East and West Antarctica that may be offset from the physiographic transition at the surface, using deep resistivity structure distinguish between modes of extensional upwelling and magmatism that may be vertically non-uniform, depth and magnitude of quasi-layered deep crustal low resistivity, particularly below West Antarctica, will be used to estimate crustal heat flux into the ice sheet base.\n", "east": 179.94691, "geometry": ["POINT(160.482115 -83.239175)"], "keywords": "Antarctica; Magnetotelluric; Potential Field; Solid Earth; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -82.13, "nsf_funding_programs": null, "persons": "Wannamaker, Philip", "project_titles": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "projects": [{"proj_uid": "p0000247", "repository": "USAP-DC", "title": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.34835, "title": "Rift Mechanisms and Thermal Regime of the Lithosphere across Beardmore Glacier Region, Central Transantarctic Mountains, from Magnetotelluric Measurements", "uid": "600102", "west": 141.01732}, {"awards": "0838729 Hemming, Sidney", "bounds_geometry": ["POLYGON((-67.2 -58,-43.98 -58,-20.76 -58,2.46 -58,25.68 -58,48.9 -58,72.12 -58,95.34 -58,118.56 -58,141.78 -58,165 -58,165 -59.2,165 -60.4,165 -61.6,165 -62.8,165 -64,165 -65.2,165 -66.4,165 -67.6,165 -68.8,165 -70,141.78 -70,118.56 -70,95.34 -70,72.12 -70,48.9 -70,25.68 -70,2.46 -70,-20.76 -70,-43.98 -70,-67.2 -70,-67.2 -68.8,-67.2 -67.6,-67.2 -66.4,-67.2 -65.2,-67.2 -64,-67.2 -62.8,-67.2 -61.6,-67.2 -60.4,-67.2 -59.2,-67.2 -58))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "Much of the inventory of East Antarctic bedrock geochronology, as well as a record of its erosional history, is preserved in Cenozoic sediments around its margin. This project is to use these sediments to understand their sub-ice provenance and the erosional history of the shield by measuring ages of multiple geo- and thermochronometers on single detrital crystals and on multiple crystals in detrital clasts (U/Pb, fission-track, and (U-Th)/He dating of zircon and apatite, and 40Ar/39Ar dating of hornblende, mica, and feldspar). The combination of multi-chronometer ages in single grains and clasts provides a powerful fingerprint of bedrock sources, allowing us to trace provenance in Eocene fluvial sandstones through Quaternary diamicts around the margin. Multiple thermochronometric (cooling) ages in the same grains and clasts also allows us to interpret the timing and rates of erosion from these bedrock sources. Delineating a distribution of bedrock age units, their sediment transport connections, and their erosional histories over the Cenozoic, will in turn allow us to test tectonic models bearing on: (1) the origin of the Gamburtsev Subglacial Mountains, (2) fluvial and topographic evolution, and (3) the history of glacial growth and erosion.", "east": 165.0, "geometry": ["POINT(48.9 -64)"], "keywords": "Antarctica; Fission Track Thermochronology; Gamburtsev Mountains; Geochronology; Marine Sediments; Solid Earth; Southern Ocean", "locations": "Southern Ocean; Antarctica; Gamburtsev Mountains", "north": -58.0, "nsf_funding_programs": null, "persons": "Hemming, Sidney R.", "project_titles": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "projects": [{"proj_uid": "p0000506", "repository": "USAP-DC", "title": "Collaborative Research: Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Erosion History and Sediment Provenance of East Antarctica from Multi-method Detrital Geo- and Thermochronology", "uid": "600094", "west": -67.2}, {"awards": "0538580 Hemming, Sidney", "bounds_geometry": ["POLYGON((60 -60,72 -60,84 -60,96 -60,108 -60,120 -60,132 -60,144 -60,156 -60,168 -60,180 -60,180 -61,180 -62,180 -63,180 -64,180 -65,180 -66,180 -67,180 -68,180 -69,180 -70,168 -70,156 -70,144 -70,132 -70,120 -70,108 -70,96 -70,84 -70,72 -70,60 -70,60 -69,60 -68,60 -67,60 -66,60 -65,60 -64,60 -63,60 -62,60 -61,60 -60))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "This project studies sediment from the ocean floor to understand Antarctica\u0027s geologic history. Glacially eroded from the Antarctic continent, these sediments may offer insight into the 99% Antarctica covered by ice. The work\u0027s central focus is determining crust formation ages and thermal histories for three key areas of East Antarctica--Prydz Bay, eastern Weddell Sea, and Wilkes Land--through a combination of petrography, bulk sediment geochemistry and radiogenic isotopes, as well as isotope chronology of individual mineral grains. One specific objective is characterizing the composition of the Gamburtsev Mountains through studies of Eocene fluvial sediments from Prydz Bay. In addition to furthering our understanding of the hidden terrains of Antarctica, these terrigenous sediments will also serve as a natural laboratory to evaluate the effects of continental weathering on the Hf/Nd isotope systematics of seawater. An important broader impact of the project is providing exciting research projects for graduate and postdoctoral students using state of the art techniques in geochemistry.", "east": 180.0, "geometry": ["POINT(120 -65)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Geochemistry; Geochronology; Isotope Data; Marine Sediments; Oceans; Prydz Bay; Solid Earth; Southern Ocean; Weddell Sea; Wilkes Land", "locations": "Weddell Sea; Southern Ocean; Prydz Bay; Wilkes Land; Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "van de Flierdt, Tina; Goldstein, Steven L.; Hemming, Sidney R.", "project_titles": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "projects": [{"proj_uid": "p0000524", "repository": "USAP-DC", "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -70.0, "title": "Antarctica\u0027s Geological History Reflected in Sedimentary Radiogenic Isotopes", "uid": "600056", "west": 60.0}, {"awards": "0440414 Steig, Eric", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This award supports a project to obtain stable isotope profiles from shallow (\u003c100 m) ice cores from East Antarctica, to add to the growing database of environmental proxy data collected under the auspices of the \"ITASE\" (International TransAntarctic Scientific Expedition) program. In Antarctica, the instrumental record of climate is particularly short (~40 years except in a few isolated locations on the coast), and ice core proxy data are the only means available for extending this record into the past. The use of stable isotopes of water (18-O/16-O and D/H ratios) from ice cores as proxies for temperature is well established for both very short (i.e. seasonal) and long timescales (centuries, millennia). Using multivariate regression methods and shallow ice cores from West Antarctica, a reconstruction of Antarctic climate over the last ~150 years has been developed which suggests the continent has been warming, on average, at a rate of ~0.2 K/century. Further improving these reconstructions is the chief motivation for further extending the US ITASE project. Ten to fifteen shallow (~100 m) from Victoria Land, East Antarctica will be obtained and analyzed. The core will be collected along a traverse route beginning at Taylor Dome and ending at the South Pole. Age-depth relationships for the cores will be determined through a combination of stable isotopes, visual stratigraphy and seasonal chemical signatures and marker horizons. Reconstructions of Antarctic climate obtained from these cores will be incorporated into the global network of paleoclimate information, which has been important in science, policy and educational contexts. The project will include graduate student and postdoctoral training and field experience.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Atmosphere; Climate; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; ITASE; Meteorology; Paleoclimate; Satellite Remote Sensing; Weather Station Data", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Steig, Eric J.", "project_titles": "Stable Isotope Studies at East Antarctic US ITASE Sites", "projects": [{"proj_uid": "p0000202", "repository": "USAP-DC", "title": "Stable Isotope Studies at East Antarctic US ITASE Sites"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ITASE", "south": -90.0, "title": "Stable Isotope Studies at East Antarctic US ITASE Sites", "uid": "600042", "west": -180.0}, {"awards": "0230276 Ward, Bess", "bounds_geometry": ["POLYGON((162 -77.2,162.16 -77.2,162.32 -77.2,162.48 -77.2,162.64 -77.2,162.8 -77.2,162.96 -77.2,163.12 -77.2,163.28 -77.2,163.44 -77.2,163.6 -77.2,163.6 -77.26,163.6 -77.32,163.6 -77.38,163.6 -77.44,163.6 -77.5,163.6 -77.56,163.6 -77.62,163.6 -77.68,163.6 -77.74,163.6 -77.8,163.44 -77.8,163.28 -77.8,163.12 -77.8,162.96 -77.8,162.8 -77.8,162.64 -77.8,162.48 -77.8,162.32 -77.8,162.16 -77.8,162 -77.8,162 -77.74,162 -77.68,162 -77.62,162 -77.56,162 -77.5,162 -77.44,162 -77.38,162 -77.32,162 -77.26,162 -77.2))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "Denitrification is the main process by which fixed nitrogen is lost from ecosystems and the regulation of this process may directly affect primary production and carbon cycling over short and long time scales. Previous investigations of the role of bioactive metals in regulating denitrification in bacteria from permanently ice-covered Lake Bonney in the Taylor Valley of East Antarctica indicated that denitrifying bacteria can be negatively affected by metals such as copper, iron, cadmium, lead, chromium, nickel, silver and zinc; and that there is a distinct difference in denitrifying activity between the east and west lobes of the lake. \n\nLow iron concentrations were found to exacerbate the potential toxicity of the other metals, while silver has the potential to specifically inhibit denitrification because of its ability to interfere with copper binding in redox proteins, such as nitrite reductase and nitrous oxide reductase. High silver concentrations might prevent the functioning of nitrous oxide reductase in the same way that simple copper limitation does, thereby causing the buildup of nitrous oxide and resulting in a nonfunctional nitrogen cycle. Other factors, such as oxygen concentration, are likely also to affect bacterial activity in Lake Bonney.\n\nThis project will investigate silver toxicity, general metal toxicity and oxygen concentration to determine their effect on denitrification in the lake by using a suite of \u0027sentinel\u0027 strains of denitrifying bacteria (isolated from the lake) incubated in Lake Bonney water and subjected to various treatments. The physiological responses of these strains to changes in metal and oxygen concentration will be quantified by flow cytometric detection of single cell molecular probes whose sensitivity and interpretation have been optimized for the sentinel strains. Understanding the relationships between metals and denitrification is expected to enhance our understanding of not only Lake Bonney\u0027s unusual nitrogen cycle, but more generally, of the potential role of metals in the regulation of microbial nitrogen transformations. The broader impacts of this work include not only a better understanding of regional biogeochemistry and global perspectives on these processes; but also the training of graduate students and a substantial outreach effort for school children.", "east": 163.6, "geometry": ["POINT(162.8 -77.5)"], "keywords": "Antarctica; Biota; CTD Data; Dry Valleys; Lake Bonney; Lake Vanda; Microbiology; Taylor Valley", "locations": "Lake Bonney; Dry Valleys; Lake Vanda; Taylor Valley; Antarctica", "north": -77.2, "nsf_funding_programs": null, "persons": "Ward, Bess", "project_titles": "Collaborative Research: What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "projects": [{"proj_uid": "p0000223", "repository": "USAP-DC", "title": "Collaborative Research: What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "uid": "600033", "west": 162.0}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": ["POINT(112.833333 -66.65)"], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "This data set includes CO2 and CH4 records derived from three ice cores obtained at Law Dome, East Antarctica, from 1987 to 1993. Law Dome is a medium size, approximately circular, (200 km dia., 1390 m high) ice sheet situated at the edge of the main East Antarctic ice sheet. The data in this set include cores drilled between 1987 and 1993 to a depth of 1199.6.", "east": 112.833333, "geometry": ["POINT(112.833333 -66.65)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Law Dome; Paleoclimate", "locations": "Antarctica; Law Dome", "north": -66.65, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Barnola, J. M.; Etheridge, David; Morgan, Vin", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -66.65, "title": "Law Dome Ice Cores Chemistry Data", "uid": "609245", "west": 112.833333}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": ["POINT(106.8 -78.4666667)"], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "This data set contains ice core chemistry, timescale, isotope, and temperature data analyzed by several investigators. In January 1998, the collaborative ice-drilling project between Russia, \nthe United States, and France at the Russian Vostok station in East Antarctica \nyielded the deepest ice core ever recovered, reaching a depth of 3,623 m. Preliminary data indicate the Vostok ice-core record \nextends through four climate cycles, with ice slightly older than 400 kyr.", "east": 106.8, "geometry": ["POINT(106.8 -78.4666667)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Isotope; Lake Vostok; Paleoclimate; Physical Properties; Temperature; Vostok Ice Core", "locations": "Antarctica; Lake Vostok", "north": -78.4666667, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Lal, Devendra; Barnola, J. M.; Petit, Jean Robert; Jouzel, Jean; Sowers, Todd A.; Brook, Edward J.; Bender, Michael; Fishcer, Hubertus; Blunier, Thomas; Ruddiman, William; Raymo, Maureen; Lorius, Claude; Chappellaz, Jerome", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -78.4666667, "title": "Vostok Ice Core Chemistry, Timescale, Isotope, and Temperature Data", "uid": "609242", "west": 106.8}, {"awards": "9527373 Dunbar, Nelia", "bounds_geometry": ["POLYGON((158.55 -75.86,158.562 -75.86,158.574 -75.86,158.586 -75.86,158.598 -75.86,158.61 -75.86,158.622 -75.86,158.634 -75.86,158.646 -75.86,158.658 -75.86,158.67 -75.86,158.67 -75.864,158.67 -75.868,158.67 -75.872,158.67 -75.876,158.67 -75.88,158.67 -75.884,158.67 -75.888,158.67 -75.892,158.67 -75.896,158.67 -75.9,158.658 -75.9,158.646 -75.9,158.634 -75.9,158.622 -75.9,158.61 -75.9,158.598 -75.9,158.586 -75.9,158.574 -75.9,158.562 -75.9,158.55 -75.9,158.55 -75.896,158.55 -75.892,158.55 -75.888,158.55 -75.884,158.55 -75.88,158.55 -75.876,158.55 -75.872,158.55 -75.868,158.55 -75.864,158.55 -75.86))"], "date_created": "Tue, 18 Feb 2003 00:00:00 GMT", "description": "This data set is the result of a study of volcanic ash and rock fragment (tephra) layers in exposed blue ice areas on Brimstone Peak (75.888S 158.55E) in East Antarctica. Tephra samples were collected between 15 November 1996 and 15 January 1997.\n\nThe Antarctic ice sheets preserve a record of the volcanic ash layers and chemical aerosol signatures of local and distant volcanic eruptions. Correlation of individual tephra layers, or sets of layers, in blue ice areas will allow a better understanding of the geometry of ice flow in these areas. Tephra layers in deep ice cores can also provide unique time-stratigraphic markers in cores that are difficult to date.\n\nData include the following information for each sample site: a general description, electron microprobe analysis, GPS location, neutron activation analysis, and a visual description of the petrography.Data are provided as Excel 97 data files, JPG map files, and GIF-formatted BSE images. Data are available via ftp.", "east": 158.67, "geometry": ["POINT(158.61 -75.88)"], "keywords": "Antarctica; Blue Ice; Brimstone Peak; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Petrography; Tephra", "locations": "Antarctica; Brimstone Peak", "north": -75.86, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dunbar, Nelia", "project_titles": "Collaborative Research: Volcanic Record in Antarctic Ice: Implications for Climatic and Eruptive History and Ice Sheet Dynamics of the South Polar Region", "projects": [{"proj_uid": "p0000065", "repository": "USAP-DC", "title": "Collaborative Research: Volcanic Record in Antarctic Ice: Implications for Climatic and Eruptive History and Ice Sheet Dynamics of the South Polar Region"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.9, "title": "Blue Ice Tephra II - Brimstone Peak", "uid": "609114", "west": 158.55}, {"awards": "9318121 Anandakrishnan, Sridhar; 9222121 Dalziel, Ian", "bounds_geometry": ["POINT(106.48 -72.28)"], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "These data describe the d18O of O2, d15N of N2, d18Oatm, and O2/N2 ratios of trapped gases in the Vostok ice core from East Antarctica. The investigator used a mass spectrometer to measure gas concentrations and isotopic compositions. Data extend to approximately 420,000 years ago. Two different age models are included.\n\nData are available in tab-delimited ASCII format via ftp.", "east": 106.48, "geometry": ["POINT(106.48 -72.28)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciology; Ice Core Records; Lake Vostok; Paleoclimate; UPLC-Q-TOF; Vostok Ice Core", "locations": "Antarctica; Lake Vostok", "north": -72.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Bender, Michael", "project_titles": "Collaborative Research: Seismic Traverse of the Byrd Subglacial Basin-Field Test", "projects": [{"proj_uid": "p0000150", "repository": "USAP-DC", "title": "Collaborative Research: Seismic Traverse of the Byrd Subglacial Basin-Field Test"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -72.28, "title": "Concentration and Isotopic Composition of O2 and N2 in Trapped Gases of the Vostok Ice Core", "uid": "609107", "west": 106.48}]

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