{"dp_type": "Dataset", "free_text": "Velocity"}
[{"awards": "1738992 Pettit, Erin C; 1929991 Pettit, Erin C", "bounds_geometry": ["POLYGON((-114 -74,-113 -74,-112 -74,-111 -74,-110 -74,-109 -74,-108 -74,-107 -74,-106 -74,-105 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105 -76,-106 -76,-107 -76,-108 -76,-109 -76,-110 -76,-111 -76,-112 -76,-113 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))"], "date_created": "Wed, 09 Apr 2025 00:00:00 GMT", "description": "GPS data spanning two years (with data gaps) at the Cavity and Channel sites AMIGOS (Automated Meteorology-Ice-Geophysics Observing System) and a temporary nearby station (BOB) on the Thwaites Eastern Ice Shelf, Antarctica. Data are reported as processed positions (latitude/longitude/height above WGS84 ellipsoid) and derived along flow velocities.\r\n\u003cbr/\u003e", "east": -104.0, "geometry": ["POINT(-109 -75)"], "keywords": "Amundsen Sea; Antarctica; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GNSS; Ice Shelf; Ice Velocity; Thwaites Glacier", "locations": "Amundsen Sea; Thwaites Glacier; Antarctica; Thwaites Glacier", "north": -74.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Truffer, Martin; Scambos, Ted; Wild, Christian; Pettit, Erin; Alley, Karen", "project_titles": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment", "projects": [{"proj_uid": "p0010162", "repository": "USAP-DC", "title": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "Thwaites Eastern Ice Shelf GPS displacements", "uid": "601925", "west": -114.0}, {"awards": "1929991 Pettit, Erin C", "bounds_geometry": ["POLYGON((-106.5 -74.5,-106.3 -74.5,-106.1 -74.5,-105.9 -74.5,-105.7 -74.5,-105.5 -74.5,-105.3 -74.5,-105.1 -74.5,-104.9 -74.5,-104.7 -74.5,-104.5 -74.5,-104.5 -74.6,-104.5 -74.7,-104.5 -74.8,-104.5 -74.9,-104.5 -75,-104.5 -75.1,-104.5 -75.2,-104.5 -75.3,-104.5 -75.4,-104.5 -75.5,-104.7 -75.5,-104.9 -75.5,-105.1 -75.5,-105.3 -75.5,-105.5 -75.5,-105.7 -75.5,-105.9 -75.5,-106.1 -75.5,-106.3 -75.5,-106.5 -75.5,-106.5 -75.4,-106.5 -75.3,-106.5 -75.2,-106.5 -75.1,-106.5 -75,-106.5 -74.9,-106.5 -74.8,-106.5 -74.7,-106.5 -74.6,-106.5 -74.5))"], "date_created": "Tue, 11 Mar 2025 00:00:00 GMT", "description": "Monthly velocity composites were produced from January 2016 to December 2022 using Sentinel-1 Interferometric Wide Swath (IW) mode using standard feature/speckle tracking procedures. From 2016 to 2021, up to 10 mosaics per month were averaged (Sentinel 1A and Sentinel 1B). After Sentinel-1B ended in December 2021, mosaics decreased to 2 per month (12-day pairs only from Sentinel 1A), producing more noisy data and larger data gaps. We used 6- and 12-day Sentinel-1 image pairs from the archive and a feature tracking window of 416 \u00d7 128 pixels (\u223c1 km in range and azimuth). We sampled the velocity field at 50 \u00d7 10 pixels before geocoding to the Antarctic Polar Stereographic projection (EPSG:3031) at 100 m resolution using the REMA mosaic DEM. DEM gaps were filled using Bedmap2 surface topography data.", "east": -104.5, "geometry": ["POINT(-105.5 -75)"], "keywords": "Antarctica; Cryosphere; Glaciology; Ice Shelf; Thwaites Glacier; Velocity", "locations": "Antarctica; Thwaites Glacier", "north": -74.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Banerjee, Debangshu; Lilien, David; Luckman, Adrian; Truffer, Martin; Wild, Christian; Pettit, Erin; Scambos, Ted; Muto, Atsuhiro; Alley, Karen", "project_titles": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment", "projects": [{"proj_uid": "p0010162", "repository": "USAP-DC", "title": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.5, "title": "Sentinel-1-derived monthly-averaged velocity components from Thwaites Eastern Ice Shelf, 2016 - 2022", "uid": "601914", "west": -106.5}, {"awards": "1643873 Hansen, Samantha; 1643798 Emry, Erica", "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, 27 Feb 2025 00:00:00 GMT", "description": "This dataset provides the shear-wave velocity model resulting from a full-waveform inversion that was constrained using long-period empirical Green\u0027s functions extracted from ambient seismic noise. The results are highlighted in Hansen and Emry (2025).", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Ambient Seismic Noise; Antarctica; Cryosphere; Full-Waveform Inversion; Seismic Tomography; Shear Wave Velocity", "locations": "Antarctica; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Emry, Erica; Hansen, Samantha", "project_titles": "Collaborative Research: Imaging Seismic Heterogeneity within the Antarctic Mantle with Full Waveform Ambient Noise Tomography", "projects": [{"proj_uid": "p0010139", "repository": "USAP-DC", "title": "Collaborative Research: Imaging Seismic Heterogeneity within the Antarctic Mantle with Full Waveform Ambient Noise Tomography"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Shear Wave Velocity of the Antarctic Upper Mantle from Full Waveform Inversion and Long Period Ambient Seismic Noise", "uid": "601909", "west": -180.0}, {"awards": "1929991 Pettit, Erin C", "bounds_geometry": ["POLYGON((-106.5 -74.5,-106.3 -74.5,-106.1 -74.5,-105.9 -74.5,-105.7 -74.5,-105.5 -74.5,-105.3 -74.5,-105.1 -74.5,-104.9 -74.5,-104.7 -74.5,-104.5 -74.5,-104.5 -74.6,-104.5 -74.7,-104.5 -74.8,-104.5 -74.9,-104.5 -75,-104.5 -75.1,-104.5 -75.2,-104.5 -75.3,-104.5 -75.4,-104.5 -75.5,-104.7 -75.5,-104.9 -75.5,-105.1 -75.5,-105.3 -75.5,-105.5 -75.5,-105.7 -75.5,-105.9 -75.5,-106.1 -75.5,-106.3 -75.5,-106.5 -75.5,-106.5 -75.4,-106.5 -75.3,-106.5 -75.2,-106.5 -75.1,-106.5 -75,-106.5 -74.9,-106.5 -74.8,-106.5 -74.7,-106.5 -74.6,-106.5 -74.5))"], "date_created": "Fri, 21 Feb 2025 00:00:00 GMT", "description": "This dataset comprises GeoTiff files that capture the yearly averages of ice-flow velocity (including x- and y-components, and flow speed) and strain rates (longitudinal, transverse, and shear) for the Thwaites Eastern Ice Shelf (TEIS) from 2013 to 2022. The velocity grids were generated using ITS_LIVE image-pair velocities available throughout the year, ensuring a consistent extent and spatial resolution for each annual composite. These composites were created by stacking all available image pairs and taking the median value for each grid cell. Small data gaps near the grounding line were filled using bilinear interpolation. Each pixel in the grid represents the median value of all available pixels during the specified period. The data are gridded at a spatial resolution of 120m in a polar stereographic projection (EPSG:3031). Speed is given in metres per day (m/yr), and strain rates are given in units/day. Additional funding was received from NE/S006419/1.", "east": -104.5, "geometry": ["POINT(-105.5 -75)"], "keywords": "Antarctica; Cryosphere; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Glaciology; Ice Shelf; Remote Sensing; Satellite Imagery; Thwaites; Thwaites Glacier; Velocity", "locations": "Thwaites Glacier; Antarctica; Thwaites; Antarctica", "north": -74.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Banerjee, Debangshu; Lilien, David; Truffer, Martin; Luckman, Adrian; Wild, Christian; Pettit, Erin; Scambos, Ted; Muto, Atsuhiro; Alley, Karen", "project_titles": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment", "projects": [{"proj_uid": "p0010162", "repository": "USAP-DC", "title": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.5, "title": "Yearly velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2013-2022", "uid": "601904", "west": -106.5}, {"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": "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": "2138277 Gallagher, Katherine", "bounds_geometry": ["POLYGON((-97.5 -55,-92.05 -55,-86.6 -55,-81.15 -55,-75.7 -55,-70.25 -55,-64.8 -55,-59.35 -55,-53.9 -55,-48.449999999999996 -55,-43 -55,-43 -57.1,-43 -59.2,-43 -61.3,-43 -63.4,-43 -65.5,-43 -67.6,-43 -69.7,-43 -71.8,-43 -73.9,-43 -76,-48.45 -76,-53.9 -76,-59.35 -76,-64.8 -76,-70.25 -76,-75.7 -76,-81.15 -76,-86.6 -76,-92.05000000000001 -76,-97.5 -76,-97.5 -73.9,-97.5 -71.8,-97.5 -69.7,-97.5 -67.6,-97.5 -65.5,-97.5 -63.4,-97.5 -61.3,-97.5 -59.2,-97.5 -57.099999999999994,-97.5 -55))"], "date_created": "Thu, 09 May 2024 00:00:00 GMT", "description": "This dataset includes daily-averaged current speed and velocity data from the Regional Ocean Modeling System. Domain covers the West Antarctic Peninsula. Simulations are from the 2006, 2007, 2010, and 2011 seasons.", "east": -43.0, "geometry": ["POINT(-70.25 -65.5)"], "keywords": "Antarctica; Cryosphere; Model Data; Ocean Currents; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "locations": "West Antarctic Shelf; Antarctica", "north": -55.0, "nsf_funding_programs": "Post Doc/Travel", "persons": "Gallagher, Katherine", "project_titles": "OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula", "projects": [{"proj_uid": "p0010349", "repository": "USAP-DC", "title": "OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Current velocity and direction data from Regional Ocean Modeling System simulations (2006-2007 \u0026 2010-2011)", "uid": "601779", "west": -97.5}, {"awards": "1744649 Christianson, Knut", "bounds_geometry": ["POLYGON((-110.338 -85.76,-109.5454 -85.76,-108.7528 -85.76,-107.9602 -85.76,-107.1676 -85.76,-106.375 -85.76,-105.5824 -85.76,-104.7898 -85.76,-103.9972 -85.76,-103.2046 -85.76,-102.412 -85.76,-102.412 -85.8266,-102.412 -85.89320000000001,-102.412 -85.9598,-102.412 -86.02640000000001,-102.412 -86.093,-102.412 -86.1596,-102.412 -86.2262,-102.412 -86.2928,-102.412 -86.35940000000001,-102.412 -86.426,-103.2046 -86.426,-103.9972 -86.426,-104.7898 -86.426,-105.5824 -86.426,-106.375 -86.426,-107.1676 -86.426,-107.9602 -86.426,-108.7528 -86.426,-109.5454 -86.426,-110.338 -86.426,-110.338 -86.35940000000001,-110.338 -86.2928,-110.338 -86.2262,-110.338 -86.1596,-110.338 -86.093,-110.338 -86.02640000000001,-110.338 -85.9598,-110.338 -85.89320000000001,-110.338 -85.8266,-110.338 -85.76))"], "date_created": "Mon, 09 Oct 2023 00:00:00 GMT", "description": "Phase-sensitive radar data collected at Hercules Dome, Antarctica. These data are processed in two ways for two separate objectives. First, repeat acquisitions between years are interfered to interpret vertical velocity. Second, polarized acquisitions are interfered to interpret crystal orientation fabric. The full processing flow is included to recreate the given data products from the included raw data.", "east": -102.412, "geometry": ["POINT(-106.375 -86.093)"], "keywords": "Antarctica; Apres; Crystal Orientation Fabric; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hercules Dome; Ice Dynamic; Ice Penetrating Radar; Radar Interferometry; Radar Polarimetry", "locations": "Hercules Dome; Antarctica", "north": -85.76, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hills, Benjamin; Holschuh, Nicholas; Hoffman, Andrew; Fudge, Tyler J; Horlings, Annika; Erwin, Emma; Steig, Eric J.; 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": -86.426, "title": "Hercules Dome ApRES Data", "uid": "601739", "west": -110.338}, {"awards": "1043761 Young, Duncan; 0230197 Holt, John; 2127606 Young, Duncan A.; 0636724 Blankenship, Donald", "bounds_geometry": ["POLYGON((-136 -74,-131.9 -74,-127.8 -74,-123.7 -74,-119.6 -74,-115.5 -74,-111.4 -74,-107.30000000000001 -74,-103.2 -74,-99.1 -74,-95 -74,-95 -74.7,-95 -75.4,-95 -76.1,-95 -76.8,-95 -77.5,-95 -78.2,-95 -78.9,-95 -79.6,-95 -80.3,-95 -81,-99.1 -81,-103.2 -81,-107.3 -81,-111.4 -81,-115.5 -81,-119.6 -81,-123.69999999999999 -81,-127.8 -81,-131.9 -81,-136 -81,-136 -80.3,-136 -79.6,-136 -78.9,-136 -78.2,-136 -77.5,-136 -76.8,-136 -76.1,-136 -75.4,-136 -74.7,-136 -74))"], "date_created": "Wed, 15 Mar 2023 00:00:00 GMT", "description": "This file contains internal radar horizon 1 (lm-MERGE-lay9-grg) for West Antarctica, collected during the SOAR/CASERTZ (1991-1996), SOAR/DVD (1999), ATRS (2001), AGASEA (2004-05) and GIMBLE (2013-2014) expeditions. Only data collected in AGASEA is contained in this specific product.\r\nThis data set is linked to PH.D thesis Muldoon, G. 2018 \"West Antarctic Ice Sheet Retreat during the Last Interglacial\"Spatial and temporal distributions of accumulation rates on the catchment of Thwaites Glacier, West Antarctica\", University of Texas at Austin\r\n https://doi.org/10.15781/T23B5WS0D\r\nThe internal radar horizon (IRH) was traced semi-automatically by Gail R. Muldoon using Haliburtons\u0027s Landmark software and picker, in a combination of 2D focused and unfocused data.\r\nDepths were calculated using a 2 way velocity in ice of 84.5 m/microsecond, and no firn correction. \r\n\r\nIsochron age is 4711 (+/- 246 ) years. \r\n\r\nFunding for this dataset as provided by NSF grants and The G. Unger Vetlesen Foundation.", "east": -95.0, "geometry": ["POINT(-115.5 -77.5)"], "keywords": "Antarchitecture; Antarctica; Ice Penetrating Radar; Isochron; Layers; Radar; Radioglaciology; Thwaites Glacier", "locations": "Thwaites Glacier; Antarctica", "north": -74.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Muldoon, Gail R.; Young, Duncan A.; Jackson, Charles; Blankenship, Donald D.", "project_titles": "Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA); Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System; Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)", "projects": [{"proj_uid": "p0000435", "repository": "USAP-DC", "title": "Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE)"}, {"proj_uid": "p0000243", "repository": "USAP-DC", "title": "Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA)"}, {"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"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -81.0, "title": "AGASEA 4.7 ka Englacial Isochron over the Thwaites Glacier Catchment", "uid": "601673", "west": -136.0}, {"awards": "2138277 Gallagher, Katherine", "bounds_geometry": ["POLYGON((-97.5 -55,-92.05 -55,-86.6 -55,-81.15 -55,-75.7 -55,-70.25 -55,-64.8 -55,-59.35 -55,-53.9 -55,-48.449999999999996 -55,-43 -55,-43 -57.1,-43 -59.2,-43 -61.3,-43 -63.4,-43 -65.5,-43 -67.6,-43 -69.7,-43 -71.8,-43 -73.9,-43 -76,-48.45 -76,-53.9 -76,-59.35 -76,-64.8 -76,-70.25 -76,-75.7 -76,-81.15 -76,-86.6 -76,-92.05000000000001 -76,-97.5 -76,-97.5 -73.9,-97.5 -71.8,-97.5 -69.7,-97.5 -67.6,-97.5 -65.5,-97.5 -63.4,-97.5 -61.3,-97.5 -59.2,-97.5 -57.099999999999994,-97.5 -55))"], "date_created": "Fri, 13 Jan 2023 00:00:00 GMT", "description": "This dataset includes daily-averaged current speed and velocity data from the Regional Ocean Modeling System. Domain covers the West Antarctic Peninsula. Simulations are from the 2008, 2009, 2018, and 2019 seasons. ", "east": -43.0, "geometry": ["POINT(-70.25 -65.5)"], "keywords": "Antarctica; Model Data; Ocean Currents; Physical Oceanography; Regional Ocean Modeling System; ROMS; West Antarctic Shelf", "locations": "Antarctica; West Antarctic Shelf", "north": -55.0, "nsf_funding_programs": "Post Doc/Travel", "persons": "Gallagher, Katherine", "project_titles": "OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula", "projects": [{"proj_uid": "p0010349", "repository": "USAP-DC", "title": "OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.0, "title": "Current velocity and direction data from Regional Ocean Modeling System simulations (2008-2009 \u0026 2018-2019)", "uid": "601656", "west": -97.5}, {"awards": "1643353 Christianson, Knut; 1744649 Christianson, Knut", "bounds_geometry": ["POLYGON((-179.9989061 -89.752739299,-143.999017884 -89.752739299,-107.999129669 -89.752739299,-71.9992414529 -89.752739299,-35.9993532372 -89.752739299,0.000534978500013 -89.752739299,36.0004231942 -89.752739299,72.0003114099 -89.752739299,108.000199626 -89.752739299,144.000087841 -89.752739299,179.999976057 -89.752739299,179.999976057 -89.7772743702,179.999976057 -89.8018094414,179.999976057 -89.8263445126,179.999976057 -89.8508795838,179.999976057 -89.875414655,179.999976057 -89.8999497262,179.999976057 -89.9244847974,179.999976057 -89.9490198686,179.999976057 -89.9735549398,179.999976057 -89.998090011,144.000087841 -89.998090011,108.000199626 -89.998090011,72.0003114099 -89.998090011,36.0004231942 -89.998090011,0.000534978499985 -89.998090011,-35.9993532372 -89.998090011,-71.9992414529 -89.998090011,-107.999129669 -89.998090011,-143.999017884 -89.998090011,-179.9989061 -89.998090011,-179.9989061 -89.9735549398,-179.9989061 -89.9490198686,-179.9989061 -89.9244847974,-179.9989061 -89.8999497262,-179.9989061 -89.875414655,-179.9989061 -89.8508795838,-179.9989061 -89.8263445126,-179.9989061 -89.8018094414,-179.9989061 -89.7772743702,-179.9989061 -89.752739299))"], "date_created": "Thu, 06 Jan 2022 00:00:00 GMT", "description": "These are ground-based radar data collected from a subglacial lake ~15 km from the geographic South Pole. Data were collected with the Autonomous phase-sensitive Radio Echo Sounder (ApRES) (Nicholls et al., 2015). The intention of this dataset is to be used for vertical velocity structure and interpretation.", "east": 179.999976057, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Apres; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; South Pole; Subglacial Lakes; Vertical Velocity", "locations": "South Pole; South Pole; Antarctica", "north": -89.752739299, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Hills, Benjamin", "project_titles": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow", "projects": [{"proj_uid": "p0010160", "repository": "USAP-DC", "title": "Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -89.998090011, "title": "South Pole Lake ApRES Radar", "uid": "601503", "west": -179.9989061}, {"awards": "1245871 McCarthy, Christine", "bounds_geometry": null, "date_created": "Thu, 23 Dec 2021 00:00:00 GMT", "description": "This data set contains text files for the experimental logs of ice-on-rock friction experiments that were conducted in a double direct shear apparatus at temperatures of -16.4 C to -2 C. There are eleven files (C28-C34, C39-C41, and C44). Each file contains 4 columns of data that correspond to time (s), vertical displacement (microns), friction, and velocity. The data were prepared by converting voltages from experimental feedbacks, to appropriate units using calibrations, as conducted separate. Miscellaneous loading and unloading data were removed and the data was filtered modestly (100 point moving average filter in matlab). The data set includes all information needed to plot friction or velocity vs. time or displacement from the beginning to end of the run. ", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "persons": "McCarthy, Christine M.; Skarbek, Rob; Savage, Heather", "project_titles": "Laboratory Study of Ice Deformation under Tidal Loading Conditions with Application to Antarctic Glaciers", "projects": [{"proj_uid": "p0010186", "repository": "USAP-DC", "title": "Laboratory Study of Ice Deformation under Tidal Loading Conditions with Application to Antarctic Glaciers"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Dataset for Tidal modulation of ice streams: Effect of periodic sliding velocity on ice friction and healing", "uid": "601497", "west": null}, {"awards": "1246353 Anderson, John; 1745055 Stearns, Leigh; 1745043 Simkins, Lauren", "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, 10 Nov 2021 00:00:00 GMT", "description": "The dataset here allows exploration of the causes and significance of Antarctic grounding-line sinuosity by coupling observations of contemporary Antarctic grounding lines and paleo-grounding lines expressed as ice-marginal landforms on the Ross Sea continental shelf. Modern grounding lines are derived from the MEaSUREs Version 2 Differential Satellite Radar Interferometry dataset with spatial resolutions of 25-120 m spanning February 1992 to December 2014 (Rignot et al., 2016; Mouginot et al., 2017). The boundaries of individual grounding lines representative of individual glacial catchments (n=664) were delineated by the inflection points of the shear strain rate, \u03b5xy (c.f Van der Veen et al., 2011). Sinuosity was calculated as the ratio of the true length, orthogonal to ice-flow direction, of the grounding lines and the straight line length between end-points and in units of km/km. Raster data were extracted at 1-km points along each grounding line; the mean was calculated for each grounding line and merged in a table with sinuosity data. A dataset of 6,275 paleo-grounding lines expressed as ice-marginal landforms on the deglaciated western Ross Sea continental shelf are used in this study, originally published by Simkins et al., 2018. The ice-marginal landforms were mapped from multibeam echo sounder data that was collected onboard the RVIB Nathaniel B. Palmer (NBP) 15-02 cruise using a Kongsberg EM122 operating in dual swath mode at 12 kHz frequency with 30-60% swath overlap (Cruise DOI: 10.7284/901477). The resulting bathymetry data was gridded at 20-40 m with decimeter vertical elevation resolution depending on water depth and sea-state. Sinuosity is calculated as a ratio of true (mapped) landform length, measured in the across paleo-ice flow direction at the crest of the landform, to the straight line distance between the mapped landform endpoints and in units of km/km. \r\n\r\nTo compare modern and paleo-grounding lines, we use a consistent length scale by segmenting the grounding lines into 2-km sections for the two datasets (modern, n=12,966; paleo, n=5,832), even though this eliminates grounding lines that are less than 2-km long and thus results in 1 modern and 3,873 paleo-grounding lines removed. The full-length and 2-km segmented groundings lines are provided as shapefiles \"InSAR_groundinglines_full\" and \"InSAR_groundinglines_2km\", the paleo-grounding lines are provided as shapefiles \"RossSea_icemarginal_full\" and \"RossSea_icemarginal_2km\", and points marking modern grounding lines retreat from repeat InSAR surveys are provided as shapefile \"InSAR_retreat_points\", all stored together in a geodatabase named \"Antarctic_groundinglines.gbd\". Additional grounding line metrics, including length, sinuosity, bed roughness, and bed slope for modern and paleo-grounding lines, and height-above-buoyancy gradient, ice-flow velocity, presence of pinning points and ice shelves are provided for modern grounding lines. \r\n\r\nThe published dataset was compiled and analyzed in the article \"Controls on circum-Antarctic grounding-line sinuosity \" by Simkins, L.M., Stearns, L.A., and Riverman, K.L, which will be submitted to a peer-review journal in November 2021.\r\n\r\nReferences\r\nMouginot, J., B. Scheuchl, and E. Rignot. 2017. MEaSUREs Antarctic Boundaries for IPY 2007-2009 from Satellite Radar, Version 2. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. \r\n\r\nRignot, E., J. Mouginot, and B. Scheuchl. 2016. MEaSUREs Antarctic Grounding Line from Differential Satellite Radar Interferometry, Version 2. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. \r\n\r\nSimkins, L. M., Greenwood, S. L., \u0026 Anderson, J. B. (2018). Diagnosing ice sheet grounding line stability from landform morphology. The Cryosphere, 12(8), 2707-2726.\r\n\r\nVan der Veen, C. J., J. C. Plummer, \u0026 L. A. Stearns. (2011). Controls on the recent speed up of Jakobshavn Isbr\u00e6, West Greenland. Journal of Glaciology, 57(204), 770-782", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Bed Roughness; Bed Slope; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Pinning Points", "locations": "Antarctica; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Simkins, Lauren; Stearns, Leigh; Riverman, Kiya", "project_titles": "Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations; Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum.", "projects": [{"proj_uid": "p0000395", "repository": "USAP-DC", "title": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum."}, {"proj_uid": "p0010269", "repository": "USAP-DC", "title": "Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Circum-Antarctic grounding-line sinuosity", "uid": "601484", "west": -180.0}, {"awards": "1738992 Pettit, Erin C", "bounds_geometry": ["POLYGON((-114 -74,-113 -74,-112 -74,-111 -74,-110 -74,-109 -74,-108 -74,-107 -74,-106 -74,-105 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105 -76,-106 -76,-107 -76,-108 -76,-109 -76,-110 -76,-111 -76,-112 -76,-113 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))"], "date_created": "Mon, 11 Oct 2021 00:00:00 GMT", "description": "This dataset includes GeoTiffs of two-year averages of ice flow velocity (including x- and y-components and flow speed) and longitudinal, transverse, and shear strain rates for the Thwaites Eastern Ice Shelf (TEIS) from 2001-2020. The grids were derived from feature tracking on MODIS, Landsat-7, and Landsat-8 imagery. Each pixel in a grid represents the median value of a stack of all available pixels for each time period. Data are gridded at a 500 m spatial resolution in a polar stereographic (EPSG:3031) projection. Speed units are m/day and strain rates are in units of /day. In addition, we provide videos of each variable (excluding x- and y-velocity components) placed alongside a MODIS image of the same extent and from around the same time to provide context. In addition to the variables noted above, we include videos for flow direction (in degrees from grid north in an EPSG:3031 projection) and a zoomed-in version of flow direction, which were calculated from the provided grids.", "east": -104.0, "geometry": ["POINT(-109 -75)"], "keywords": "Antarctica; Glaciology; Ice Shelf; Ice Velocity; Strain Rate; Thwaites Glacier", "locations": "Antarctica; Thwaites Glacier", "north": -74.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "persons": "Alley, Karen; Wild, Christian; Scambos, Ted; Muto, Atsu; Pettit, Erin; Truffer, Martin; Wallin, Bruce; Klinger, Marin", "project_titles": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment", "projects": [{"proj_uid": "p0010162", "repository": "USAP-DC", "title": "NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -76.0, "title": "Two-year velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2001-2020", "uid": "601478", "west": -114.0}, {"awards": "1245871 McCarthy, Christine", "bounds_geometry": null, "date_created": "Fri, 30 Jul 2021 00:00:00 GMT", "description": "This data set contains rate and state frictional parameters for ice-on-rock friction experiments that were conducted in a double direct shear apparatus as temperatures of -16.4 C to -2 C. The frictional parameters were deteremined by directly fitting the frictional response to controlled, harmonic oscillations in load point velocity. The data set includes all information needed to reproduce the fits, as well as tables of the frictional parameters for both the aging and slip law forms of frictional state evolution.", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Skarbek, Rob; McCarthy, Christine M.; Savage, Heather", "project_titles": "Laboratory Study of Ice Deformation under Tidal Loading Conditions with Application to Antarctic Glaciers", "projects": [{"proj_uid": "p0010186", "repository": "USAP-DC", "title": "Laboratory Study of Ice Deformation under Tidal Loading Conditions with Application to Antarctic Glaciers"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Rate-state friction parameters for ice-on-rock oscillation experiments", "uid": "601467", "west": null}, {"awards": "1643795 Mikesell, Thomas", "bounds_geometry": ["POLYGON((-134.5 -75,-130.85 -75,-127.2 -75,-123.55 -75,-119.9 -75,-116.25 -75,-112.6 -75,-108.95 -75,-105.3 -75,-101.65 -75,-98 -75,-98 -75.85,-98 -76.7,-98 -77.55,-98 -78.4,-98 -79.25,-98 -80.1,-98 -80.95,-98 -81.8,-98 -82.65,-98 -83.5,-101.65 -83.5,-105.3 -83.5,-108.95 -83.5,-112.6 -83.5,-116.25 -83.5,-119.9 -83.5,-123.55 -83.5,-127.2 -83.5,-130.85 -83.5,-134.5 -83.5,-134.5 -82.65,-134.5 -81.8,-134.5 -80.95,-134.5 -80.1,-134.5 -79.25,-134.5 -78.4,-134.5 -77.55,-134.5 -76.7,-134.5 -75.85,-134.5 -75))"], "date_created": "Fri, 15 Jan 2021 00:00:00 GMT", "description": "This data set includes observations of Rayleigh and Love wave group and phase velocity dispersion curves from ambient noise crosscorrelation functions. The data set includes the corresponding shear wave velocity model produced by joint inversion of these dispersion curves. This investigators developed a new crust and upper mantle model directly beneath the seismic stations used in this study. Data are in NetCDF and GeoCSV formats. The Python code used to generate the NetCDF files from the GeoCSV files is also contained in the data set.", "east": -98.0, "geometry": ["POINT(-116.25 -79.25)"], "keywords": "Antarctica; Crust; Moho; Seismic Tomography; Seismology; Seismometer; Shear Wave Velocity; Surface Wave Dispersion; West Antarctica", "locations": "Antarctica; West Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Mikesell, Dylan", "project_titles": "Collaborative Research: Monitoring Antarctic Ice Sheet Changes with Ambient Seismic Noise Methods", "projects": [{"proj_uid": "p0010155", "repository": "USAP-DC", "title": "Collaborative Research: Monitoring Antarctic Ice Sheet Changes with Ambient Seismic Noise Methods"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "POLENET", "south": -83.5, "title": "2D shear-wave velocity model across the West Antarctic Rift System from POLENET-ANET seismic data", "uid": "601423", "west": -134.5}, {"awards": null, "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": "Tue, 05 May 2020 00:00:00 GMT", "description": "VELMAP is a compilation of ice velocity data of the Antarctic ice sheet and is intended for use by the polar scientific community. The data are presented in tabular form (ASCII format), containing latitude, longitude, speed, bearing, and error ranges. A metadata header describes the source of the data, the time of measurement, and gives details on measurement accuracy and precision.\r\n\r\nThe data sets were contributed by several investigators, in most cases from already-published work. Both in situ and image-based methods are used. References for the data sets are included with the data tables.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Scambos, Ted", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "VELMAP", "uid": "601317", "west": -180.0}, {"awards": "1043623 Miller, Scott", "bounds_geometry": ["POLYGON((-180 -57,-169.5 -57,-159 -57,-148.5 -57,-138 -57,-127.5 -57,-117 -57,-106.5 -57,-96 -57,-85.5 -57,-75 -57,-75 -59.1,-75 -61.2,-75 -63.3,-75 -65.4,-75 -67.5,-75 -69.6,-75 -71.7,-75 -73.8,-75 -75.9,-75 -78,-85.5 -78,-96 -78,-106.5 -78,-117 -78,-127.5 -78,-138 -78,-148.5 -78,-159 -78,-169.5 -78,180 -78,178.3 -78,176.6 -78,174.9 -78,173.2 -78,171.5 -78,169.8 -78,168.1 -78,166.4 -78,164.7 -78,163 -78,163 -75.9,163 -73.8,163 -71.7,163 -69.6,163 -67.5,163 -65.4,163 -63.3,163 -61.2,163 -59.1,163 -57,164.7 -57,166.4 -57,168.1 -57,169.8 -57,171.5 -57,173.2 -57,174.9 -57,176.6 -57,178.3 -57,-180 -57))"], "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 NBP1210 conducted in 2013. The files are of XLS format", "east": -75.0, "geometry": ["POINT(-136 -67.5)"], "keywords": "Air-Sea Flux; Air Temperature; Amundsen Sea; Antarctica; Antarctic Peninsula; Atmosphere; CO2; Flux; Meteorology; NBP1210; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Water Temperature; Wind Direction; Wind Speed", "locations": "Antarctica; Antarctic Peninsula; Amundsen Sea; Ross Sea; Southern Ocean", "north": -57.0, "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": -78.0, "title": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1210", "uid": "601309", "west": 163.0}, {"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": "1443471 Koutnik, Michelle", "bounds_geometry": ["POINT(-98.16 -89.99)"], "date_created": "Wed, 25 Mar 2020 00:00:00 GMT", "description": "The South Pole Ice Core (SPICEcore), which spans the past 54,300 years, was drilled far from an ice divide such that ice recovered at depth originated upstream of the core site. If the climate is different upstream, the climate history recovered from the core will be a combination of the upstream conditions advected to the core site and temporal changes. Here, we evaluate the impact of ice advection on two fundamental records from SPICEcore: accumulation rate and water isotopes. We determined past locations of ice deposition based on GPS measurements of the modern velocity field spanning 100 km upstream, where ice of ~20 ka age would likely have originated. Beyond 100 km, there are no velocity measurements, but ice likely originates from Titan Dome, an additional 90 km distant. Shallow radar measurements extending 100 km upstream from the core site reveal large (~20%) variations in accumulation but no significant trend. Water isotope ratios, measured at 12.5 km intervals for the first 100 km of the flowline, show a decrease with elevation of -0.008\u2030 m-1 for \u03b418O. Advection adds approximately 1\u2030 for \u03b418O to the LGM-to-modern change. We also use an existing ensemble of continental ice-sheet model runs to assess the ice sheet elevation change through time. The magnitude of elevation change is likely small and the sign uncertain. Assuming a lapse rate of 10\u00b0C per km of elevation, the inference of LGM-to-modern temperature change is ~1.4\u00b0C smaller than if the flow from upstream is not considered. ", "east": -98.16, "geometry": ["POINT(-98.16 -89.99)"], "keywords": "Antarctica; Ice Core Data; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -89.99, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Fudge, T. J.", "project_titles": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core", "projects": [{"proj_uid": "p0000200", "repository": "USAP-DC", "title": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -89.99, "title": "SPICEcore Advection", "uid": "601266", "west": -98.16}, {"awards": "1643551 Hansen, Samantha", "bounds_geometry": null, "date_created": "Tue, 10 Mar 2020 00:00:00 GMT", "description": "Dataset includes information on all A- and B-ranked earthquakes (see Hansen et al., 2020) recorded by the Antarctic TAMNNET seismic array that were examined for ULVZ evidence. Information on their attenuation (t*) parameter, signal-to-noise ratio, core-mantle boundary bouncepoint location, and average remainder trace standard deviation are also provided. The provided figure indicates where ULVZ evidence has been found and where possible ULVZ evidence may be indicated.", "east": null, "geometry": null, "keywords": "Antarctica; Core-Mantle Boundary; ScP; Southern Hemisphere; Ultra-Low Velocity Zones", "locations": "Antarctica; Antarctica; Southern Hemisphere", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Hansen, Samantha; Carson, Sarah; Garnero, Edward; Yu, Shule; Rost, Sebastian", "project_titles": "Collaborative Research: Antarctic Seismic Investigations of ULVZ Structure", "projects": [{"proj_uid": "p0010136", "repository": "USAP-DC", "title": "Collaborative Research: Antarctic Seismic Investigations of ULVZ Structure"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Investigating Ultra-low Velocity Zones (ULVZs) using an Antarctic Dataset", "uid": "601265", "west": null}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": ["POLYGON((150 -72,152 -72,154 -72,156 -72,158 -72,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,170 -72.3,170 -72.6,170 -72.9,170 -73.2,170 -73.5,170 -73.8,170 -74.1,170 -74.4,170 -74.7,170 -75,168 -75,166 -75,164 -75,162 -75,160 -75,158 -75,156 -75,154 -75,152 -75,150 -75,150 -74.7,150 -74.4,150 -74.1,150 -73.8,150 -73.5,150 -73.2,150 -72.9,150 -72.6,150 -72.3,150 -72))"], "date_created": "Wed, 31 Jul 2019 00:00:00 GMT", "description": "The Transantarctic Mountains (TAMs) are the largest non-collisional mountain range on Earth. Their origin, as well as the origin of the Wilkes Subglacial Basin (WSB) along the inland side of the TAMs, have been widely debated, and a key constraint to distinguish between competing models is the underlying crustal structure. Previous investigations have examined this structure but have primarily focused on a small region of the central TAMs near Ross Island, providing little along-strike constraint. In this study, we use data from the new Transantarctic Mountains Northern Network and from five stations operated by the Korea Polar Research Institute to investigate the crustal structure beneath a previously unexplored portion of the TAMs. Using S-wave receiver functions and Rayleigh wave phase velocities, crustal thickness and average crustal shear velocity (\uf8e5Vs) are resolved within \u00b14 km and \u00b10.1 km/s, respectively. The crust thickens from ~20 km near the Ross Sea coast to ~46 km beneath the northern TAMs, which is somewhat thicker than that imaged in previous studies beneath the central TAMs. The crust thins to ~41 km beneath the WSB.\uf8e5Vs ranges from ~3.1-3.9 km/s, with slower velocities near the coast. Our findings are consistent with a flexural origin for the TAMs and WSB, where these features result from broad flexure of the East Antarctic lithosphere and uplift along its western edge due to thermal conduction from hotter mantle beneath West Antarctica. Locally thicker crust may explain the ~1 km of additional topography in the northern TAMs compared to the central TAMs.", "east": 170.0, "geometry": ["POINT(160 -73.5)"], "keywords": "Antarctica; Transantarctic Mountains", "locations": "Antarctica; Transantarctic Mountains", "north": -72.0, "nsf_funding_programs": "Antarctic Earth Sciences", "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": -75.0, "title": "Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins", "uid": "601194", "west": 150.0}, {"awards": "1246296 Yen, Jeannette", "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, 26 Jul 2018 00:00:00 GMT", "description": "A portable tomographic particle image velocimetry (tomographic PIV) system is described. The system was successfully deployed in Antarctica to study shelled Antarctic pteropods (Limacina helicina antarctica) \u2013 a delicate organism with an unusual propulsion mechanism. The experimental setup consists of a free-standing frame assembled with optical rails, thus avoiding the need for heavy and bulky equipment (e.g. an optical table). The cameras, lasers, optics, and tanks are all rigidly supported within the frame assembly. The results indicate that the pteropods flap their parapodia (or \u201cwings\u201d) downward during both power and recovery strokes, which is facilitated by the pitching of their shell. Shell pitching significantly alters the flapping trajectory, allowing the pteropod to move vertically and/or horizontally. The pronation and supination of the parapodia, together with the figure eight motion during flapping, suggest similarities with insect flight. The volumetric velocity field surrounding the freely-swimming pteropod reveals the generation of an attached vortex ring connecting the leading edge vortex to the trailing edge vortex during power stroke, and a presence of a leading-edge vortex during recovery stroke. These vortex structures play a major role in accelerating the organism vertically and indicate that forces generated on the parapodia during flapping constitute both lift and drag. After completing each stroke, two vortex rings are shed into the wake of the pteropod. The complex combination of body kinematics (parapodia flapping, shell pitch, saw-tooth trajectory), flow structures, and resulting force balance may be significantly altered by thinning of the pteropod shell, thus making pteropods an indicator of the detrimental effects of ocean acidification.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Biota; Glaciology", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Adhikari, Deepak; Webster, Donald R; Yen, Jeannette", "project_titles": "Collaborative Research: Pteropod Swimming Behavior as a Bio Assay for Ocean Acidification", "projects": [{"proj_uid": "p0000139", "repository": "USAP-DC", "title": "Collaborative Research: Pteropod Swimming Behavior as a Bio Assay for Ocean Acidification"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tomographic PIV measurements of swimming shelled Antarctic pteropod", "uid": "601108", "west": -180.0}, {"awards": "1443126 MacAyeal, Douglas", "bounds_geometry": ["POLYGON((166.02819 -77.887495,166.053634 -77.887495,166.079078 -77.887495,166.104522 -77.887495,166.129966 -77.887495,166.15541 -77.887495,166.180854 -77.887495,166.206298 -77.887495,166.231742 -77.887495,166.257186 -77.887495,166.28263 -77.887495,166.28263 -77.8926145,166.28263 -77.897734,166.28263 -77.9028535,166.28263 -77.907973,166.28263 -77.9130925,166.28263 -77.918212,166.28263 -77.9233315,166.28263 -77.928451,166.28263 -77.9335705,166.28263 -77.93869,166.257186 -77.93869,166.231742 -77.93869,166.206298 -77.93869,166.180854 -77.93869,166.15541 -77.93869,166.129966 -77.93869,166.104522 -77.93869,166.079078 -77.93869,166.053634 -77.93869,166.02819 -77.93869,166.02819 -77.9335705,166.02819 -77.928451,166.02819 -77.9233315,166.02819 -77.918212,166.02819 -77.9130925,166.02819 -77.907973,166.02819 -77.9028535,166.02819 -77.897734,166.02819 -77.8926145,166.02819 -77.887495))"], "date_created": "Tue, 24 Jul 2018 00:00:00 GMT", "description": "Over 2 Austral summer periods in 2015/6 and 2016/17, up to 12 geodetic GPS receivers were deployed on the McMurdo Ice Shelf to study its vertical deflection in response to moving meltwater loads. (5 GPS were deployed in 2015/16, 12 in 2016/17.) The GPS receivers and antennas were supplied by UNAVCO and were Trimble NetR9\u2019s and Zephyr Geodetic, respectively. The GPS receivers were stationary for the entire field seasons (were never moved). Following each field season, the GPS data were processed using MIT software called TRACK, which is part of the GAMIT package. The UNAVCO-run base station at McMurdo Station, approximately 16 km away from the field area, was used as part of the processing.", "east": 166.28263, "geometry": ["POINT(166.15541 -77.9130925)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity; Ice Shelf; Ice-Shelf Flexure; Snow/ice; Snow/Ice; Surface Melt", "locations": "Antarctica", "north": -77.887495, "nsf_funding_programs": "Antarctic Glaciology", "persons": "MacAyeal, Douglas; Banwell, Alison", "project_titles": "Impact of Supraglacial Lakes on Ice-Shelf Stability", "projects": [{"proj_uid": "p0000138", "repository": "USAP-DC", "title": "Impact of Supraglacial Lakes on Ice-Shelf Stability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.93869, "title": "McMurdo Ice Shelf GPS survey of vertical motion", "uid": "601107", "west": 166.02819}, {"awards": "1443471 Koutnik, Michelle", "bounds_geometry": ["POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))"], "date_created": "Tue, 29 May 2018 00:00:00 GMT", "description": "These data indicate the positions and velocities of a network of stakes emplaced in the vicinity of South Pole during 2015-2018. They were collected by resurveying emplaced poles over the course of 1-2 years.", "east": 180.0, "geometry": ["POINT(145 -89.5)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Velocity", "locations": "Antarctica", "north": -89.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Lilien, David; Fudge, T. J.; Koutnik, Michelle; Conway, Howard; Waddington, Edwin D.", "project_titles": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core", "projects": [{"proj_uid": "p0000200", "repository": "USAP-DC", "title": "Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "South Pole area GPS velocities", "uid": "601100", "west": 110.0}, {"awards": "1341585 Sorlien, Christopher", "bounds_geometry": ["POLYGON((-180 -73.22,-179.17 -73.22,-178.34 -73.22,-177.51 -73.22,-176.68 -73.22,-175.85 -73.22,-175.02 -73.22,-174.19 -73.22,-173.36 -73.22,-172.53 -73.22,-171.7 -73.22,-171.7 -73.765,-171.7 -74.31,-171.7 -74.855,-171.7 -75.4,-171.7 -75.945,-171.7 -76.49,-171.7 -77.035,-171.7 -77.58,-171.7 -78.125,-171.7 -78.67,-172.53 -78.67,-173.36 -78.67,-174.19 -78.67,-175.02 -78.67,-175.85 -78.67,-176.68 -78.67,-177.51 -78.67,-178.34 -78.67,-179.17 -78.67,180 -78.67,178.56 -78.67,177.12 -78.67,175.68 -78.67,174.24 -78.67,172.8 -78.67,171.36 -78.67,169.92 -78.67,168.48 -78.67,167.04 -78.67,165.6 -78.67,165.6 -78.125,165.6 -77.58,165.6 -77.035,165.6 -76.49,165.6 -75.945,165.6 -75.4,165.6 -74.855,165.6 -74.31,165.6 -73.765,165.6 -73.22,167.04 -73.22,168.48 -73.22,169.92 -73.22,171.36 -73.22,172.8 -73.22,174.24 -73.22,175.68 -73.22,177.12 -73.22,178.56 -73.22,-180 -73.22))"], "date_created": "Fri, 25 May 2018 00:00:00 GMT", "description": "This data set includes digital 1 km grids of sub-bottom \n\tstratigraphy of most of Ross Sea. In addition to acoustic basement (same as top\n\tsyn-rift sedimentary rocks in Central Trough and probably other basins), these\n\tgrids include Oligocene and Miocene horizons that are unconformities in most\n\tareas. A sea floor grid is also included. Except for the sea floor grid, the\n\tgrids are trimmed to be relatively close to control of interpreted seismic\n\tstratigraphy. The grids are provided in two way travel time and in depth. Math\n\tcan be performed on the corresponding time and depth grids to recreate the 3D\n\tinterval velocity model that was used. The velocity of the water used was 1450\n\tm/s. More detailed descriptions of the work are found in the Final NSF report\n\tfor PLR1341585 by C. Sorlien, B. Luyendyk, and D. Wilson. The grids are\n\tcontinuous so are merged with the sea floor where there is outcrop, or with\n\tbasement if there is onlap, or with a young unconformity where there is\n\tsub-bottom truncation. The filenames include the name of the horizon\n\t(unconformity) and whether they are in time or depth. \\\"etc.\\\" means there are\n\ttwo or more horizons that have been merged. Most of the horizons are named and\n\tdefined in the ANTOSTRAT (1995) atlas. The starting points for many of these\n\thorizons are ANTOSTRAT [1995] near DSDP sites 273, 272, and 270. In other areas\n\twe deviate from the interpretation of ANTOSTRAT [1995]. late Oligocene through\n\tmiddle Miocene horizons, interpreted very close to the ANTOSTRAT [1995] at DSDP\n\tSite 273 in Central Trough, are much deeper in our interpretation within Terror\n\tRift. These horizon grids usually include the sea floor where there is outcrop\n\tor acoustic basement (top syn-rift in some basins) where there is onlap. \n\n\n\tANTOSTRAT (1995), Seismic Stratigraphic Atlas of the Ross Sea, in Geology and\n\tSeismic Stratigraphy of the Antarctic Margin, edited by A. K. Cooper, Barker,\n\tP. F., Brancolini, G., 22 plates, American Geophysical Union, Washington,\n\tD.C.", "east": -171.7, "geometry": ["POINT(176.95 -75.945)"], "keywords": "Antarctica; Continental Margin; Geology/Geophysics - Other; Marine Geoscience; Miocene; Oligocene; Seismic Reflection", "locations": "Antarctica", "north": -73.22, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Sorlien, Christopher; Wilson, Douglas S.", "project_titles": "Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea", "projects": [{"proj_uid": "p0000271", "repository": "USAP-DC", "title": "Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.67, "title": "Ross Sea unconformities digital grids in depth and two-way time", "uid": "601098", "west": 165.6}, {"awards": "0944307 Conway, Howard", "bounds_geometry": ["POLYGON((-162.83 -79.15,-162.637 -79.15,-162.444 -79.15,-162.251 -79.15,-162.058 -79.15,-161.865 -79.15,-161.672 -79.15,-161.479 -79.15,-161.286 -79.15,-161.093 -79.15,-160.9 -79.15,-160.9 -79.1885037,-160.9 -79.2270074,-160.9 -79.2655111,-160.9 -79.3040148,-160.9 -79.3425185,-160.9 -79.3810222,-160.9 -79.4195259,-160.9 -79.4580296,-160.9 -79.4965333,-160.9 -79.535037,-161.093 -79.535037,-161.286 -79.535037,-161.479 -79.535037,-161.672 -79.535037,-161.865 -79.535037,-162.058 -79.535037,-162.251 -79.535037,-162.444 -79.535037,-162.637 -79.535037,-162.83 -79.535037,-162.83 -79.4965333,-162.83 -79.4580296,-162.83 -79.4195259,-162.83 -79.3810222,-162.83 -79.3425185,-162.83 -79.3040148,-162.83 -79.2655111,-162.83 -79.2270074,-162.83 -79.1885037,-162.83 -79.15))"], "date_created": "Thu, 16 Nov 2017 00:00:00 GMT", "description": "Ground-based radar data include radar echograms and .mat files of internal stratigraphy. Also included are picks of ice thickness and surface elevation. \u003cbr\u003e GPS data include positions of 142 poles set in 2010 and resurveyed in 2012. Also given are velocity vectors for the poles. ", "east": -160.9, "geometry": ["POINT(-161.865 -79.3425185)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; GPS Data; Ice Velocity; Navigation; Radar; Roosevelt Island; Ross Sea", "locations": "Roosevelt Island; Antarctica; Ross Sea", "north": -79.15, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "persons": "Conway, Howard", "project_titles": "Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island", "projects": [{"proj_uid": "p0000272", "repository": "USAP-DC", "title": "Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.535037, "title": "Roosevelt Island: Radar and GPS", "uid": "601070", "west": -162.83}, {"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, 20 Apr 2017 00:00:00 GMT", "description": "Using data from the Transantarctic Mountains (TAMs) Northern Network, the shear wave velocity structure beneath the northern TAMs was investigated with surface wave tomography. Rayleigh wave phase velocities were calculated using a two-plane wave approximation and were then inverted for shear velocity structure. The resulting model shows a low velocity zone (~4.24 km/s) at ~160 km depth offshore and adjacent to Mt. Melbourne that extends inland and vertically upwards to ~100 km depth beneath the northern TAMs and Victoria Land. Another low velocity zone (~4.16-4.24 km/s) is also seen at ~150 km depth beneath Ross Island, and relatively slow velocities (~4.24-4.32 km/s) along the Terror Rift connect the two low velocity zones. This structure has been interpreted to reflect rift-related decompression melting along the TAMs front, which would provide thermal buoyancy to uplift 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": "Transantarctic Mountains; Antarctica", "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 Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains", "uid": "601018", "west": 153.327}, {"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": "1043649 Hock, Regine", "bounds_geometry": ["POINT(-61 -62.75)", "POINT(-57.5 -61.75)"], "date_created": "Wed, 17 Feb 2016 00:00:00 GMT", "description": "The data contain the time series totals of SAR derived detrended surface velocities from Livingston Island, as well as GeoTiff files generated from intensity tracking of Synthetic Aperture Radar (SAR) imagery. The images include average annual velocity and ice thickness of King George Island, and average annual velocity, ice thickness, and a digital elevation model of Livingston Island.", "east": -57.5, "geometry": ["POINT(-61 -62.75)", "POINT(-57.5 -61.75)"], "keywords": "Antarctica; Antarctic Peninsula; Digital Elevation Model; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Thickness; Ice Velocity", "locations": "Antarctic Peninsula; Antarctica", "north": -61.75, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Osmanoglu, Batuhan; Hock, Regine", "project_titles": "Contribution of Western Antarctic Peninsula glaciers to sea level rise: Separation of the dynamic and climatic components", "projects": [{"proj_uid": "p0000054", "repository": "USAP-DC", "title": "Contribution of Western Antarctic Peninsula glaciers to sea level rise: Separation of the dynamic and climatic components"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -62.75, "title": "King George and Livingston Islands: Velocities and Digital Elevation Model", "uid": "609667", "west": -61.0}, {"awards": "0632399 Jefferies, Stuart", "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": "The ultimate goal of this project is to determine the structure and dynamics of the Sun\u0027s atmosphere, assess the role of MHD waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun\u0027s atmosphere couples to the solar interior. As the solar atmosphere is \u0027home\u0027 to many of the solar phenomena that can have a direct impact on the biosphere, including flares, coronal mass ejections, and the solar wind, the broader impact of such studies is that they will lead to an improved understanding of the Sun-Earth connection. \nUnder the current award we have developed a suite of instruments that can simultaneously image the line-of-sight Doppler velocity and longitudinal magnetic field at four heights in the solar atmosphere at high temporal cadence. The instruments use magneto-optical filters (see Cacciani, Moretti and Rodgers, Solar Physics 174, p.115, 2004) tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), 770 nm (K) and 1083 nm (He). These lines sample the solar atmosphere from the mid-photosphere to the high-chromosphere. \nA proof-of-concept run was made in the Austral summer of 2007/2008 using the Na and K versions of the instruments. Here we recorded over 40 hours of full-disk, intensity images of the Sun in the red and blue wings of the Na and K Fraunhofer lines, in both right- and left-circularly polarized light. The images were obtained at a rate of one every five seconds with a nominal spatial resolution of 4 arc-seconds. The run started at 09:44 UT on February 2, 2008 and ended at 03:30 UT on February 4, 2008.\nData Quality Assessment:\nThe temperature controls of the instrument housings were unable to fully compensate for the harse Antartic winds encountered during the observing run. This led to large (~15 C) temperature swings which adversely affected the instruments (and thus data quality) in two ways: 1) Crystals of Na and K were deposited on the magneto-optical filter windows leading to \"hot spots\" in the images. These \"hot spots\" come and go with time as the temperature changes. 2) The changing temperature caused the optical rails to contract and expand causing the final images to go in- and out-of-focus, thus reducing the resolution to greater than 4 arc-seconds. Both these effect are worse in the K data.\nDespite these problems, the intensity images can be combined to provide magnetic images that show a very high sensitivity (\u003c 5 Gauss in a 5 second integration).\nData Description:\nThe raw data are stored as a series of 1024x1024x4 FITS images. The format is: blue image (left circulary polarized light), blue image (right circularly polarized light), red image (left circulary polarized light), red image (right circularly polarized light).\nThe naming convention for the images is: Type_Instrument_Day_hour_minutes_seconds\nwhere Type is I (intensity), F (flatfield), D (dark)\n Instrument is 0 (Na), 1 (K)\n Day is the day number from the beginning of the year where January 1 is day 0\nFor example, I_0_32_12_34_40.fits is an intensity image taken with the Na instrument at 12:34.40 UT on February 2, 2008.\nNotes: \n1) The flatfield images were acquired by moving a diffuser in front of the Sun during the integration. The resulting images therefore have to be corrected for residual low-spatial frequencies due to the non-flat nature of the light source.\n2) Each FITS file header contains a variety of information on the observation, e.g.,\nF_CNTO\t: number of summed frames in each 5 second integration (*)\nFPS\t\t: Camera frame rate (Frames Per Second)\nFLIP\t: Rate at which the half-wave rotator (magnetic switch) was switched\nINT_PER\t: Integration time (in seconds)\nMOF\t\t: Temperature of magneto-optical filter cell\nWS\t\t: Temperature of wing selector cell\nTEMP_0\t: Temperature of camera 0\nTEMP_1\t: Temperature of camera 1\nTEMP_2\t: Temperature inside instrument (location 1)\nTEMP_3\t: Temperature of narrowband filter\nTEMP_5\t: Temperature of magnets surrounding MOF cell\nTEMP_6\t: Temperature inside instrument (location 2)\nTEMP_7\t: Temperature of housing for magnetic switch\n(*) This is the frame count for the camera. The number of frames in each image for the two different polarization states, is half this number.\nThe measured temperatures are only coarse measurements.\n3) Due to reflection in the final polarizing beam splitter (which separates the \"red\" and \"blue\" signals into the two cameras), the camera 1 data need to \"reversed\" along the x-axis (i.e. listed as [1024:1] instead of [1:1024])\n4) Line-of-sight velocity and magnetic field images are generated from the observed intensity images. Doppler images as (red-blue)/(red+blue), magnetic images as the difference between the Doppler images\nfor right- and left-circularly polarized light.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Cosmos; Satellite Remote Sensing; Sun", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Jefferies, Stuart M.", "project_titles": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "projects": [{"proj_uid": "p0000526", "repository": "USAP-DC", "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tomographic Imaging of the Velocity and Magnetic Fields in the Sun\u0027s Atmosphere", "uid": "600152", "west": -180.0}, {"awards": "0944794 Winberry, J. Paul", "bounds_geometry": ["POLYGON((-165 -83.75,-164 -83.75,-163 -83.75,-162 -83.75,-161 -83.75,-160 -83.75,-159 -83.75,-158 -83.75,-157 -83.75,-156 -83.75,-155 -83.75,-155 -83.85,-155 -83.95,-155 -84.05,-155 -84.15,-155 -84.25,-155 -84.35,-155 -84.45,-155 -84.55,-155 -84.65,-155 -84.75,-156 -84.75,-157 -84.75,-158 -84.75,-159 -84.75,-160 -84.75,-161 -84.75,-162 -84.75,-163 -84.75,-164 -84.75,-165 -84.75,-165 -84.65,-165 -84.55,-165 -84.45,-165 -84.35,-165 -84.25,-165 -84.15,-165 -84.05,-165 -83.95,-165 -83.85,-165 -83.75))"], "date_created": "Thu, 17 Sep 2015 00:00:00 GMT", "description": "These data contain ice velocity measurements obtained from seismic and GPS recordings during the 2010 and 2011 Antarctic field seasons.", "east": -155.0, "geometry": ["POINT(-160 -84.25)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Whillans Ice Stream", "locations": "Whillans Ice Stream; Antarctica", "north": -83.75, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Wiens, Douglas; Winberry, Paul; Anandakrishnan, Sridhar; Alley, Richard", "project_titles": "Collaborative Research: Geophysical Study of Ice Stream Stick-slip Dynamics", "projects": [{"proj_uid": "p0000053", "repository": "USAP-DC", "title": "Collaborative Research: Geophysical Study of Ice Stream Stick-slip Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.75, "title": "Whillans Ice Stream Stick-slip", "uid": "609632", "west": -165.0}, {"awards": "0838811 Sergienko, Olga", "bounds_geometry": ["POINT(0 -78)"], "date_created": "Mon, 14 Apr 2014 00:00:00 GMT", "description": "This data set consists of outputs of several numerical models simulating ice stream flow over undulated bed, interaction of ice stream flow, and subglacial and supraglacial hydraulic systems. All simulations are performed for idealized geometries using finite-element models.", "east": 0.0, "geometry": ["POINT(0 -78)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; Ice Thickness; Ice Velocity", "locations": "Antarctica", "north": -78.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Sergienko, Olga", "project_titles": "Model Investigation of Ice Stream/Subglacial Lake Systems", "projects": [{"proj_uid": "p0000045", "repository": "USAP-DC", "title": "Model Investigation of Ice Stream/Subglacial Lake Systems"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Interaction of Ice Stream Flow with Heterogeneous Beds", "uid": "609583", "west": 0.0}, {"awards": "1139739 Hansen, Samantha", "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, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: Numerous candidate models for the geologic processes that have shaped the Antarctic continent have been proposed. To discriminate between them, detailed images of the upper mantle structure are required; however, the only existing continental-scale images of seismic structure beneath Antarctica lack sufficient resolution to delineate important, diagnostic features. Using newly available data from various Antarctic seismic networks, the PI will employ the adaptively parameterized tomography method to develop a high-resolution, continental-scale seismic velocity model for all of Antarctica. The proposed tomography method combines regional seismic travel-time datasets in the context of a global model to create a composite continental-scale model of upper mantle structure. The proposed method allows for imaging of finer structure in areas with better seismic ray coverage while simultaneously limiting the resolution of features in regions with less coverage. This research will help advance understanding of important global processes, such as craton formation, mountain building, continental rifting and associated magmatism. Additionally, the proposed research will have important impacts on other fields of Antarctic science. Constraints provided by tomographic results can be used to develop thermal models of the lithosphere needed to characterize the history and dynamics of ice sheets. Also, further constraints on lithospheric structure are required by climate-ice models, which are focused on understanding the cooling history of the Antarctic continent.\n\nBroader impacts: The PI is a new faculty member at the University of Alabama after having been funded as a National Science Foundation Postdoctoral Fellow in Polar Regions Research. The graduate student supported by this project is new to polar research. Through the UA-Tuscaloosa Magnet School partnership program, the PI will educate K-12 students about the Antarctic environment and associated career opportunities through various online and hands-on activities. University of Alabama dedicates a significant percentage of its enrollment space to underrepresented groups.\n", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Geology/Geophysics - Other; Lithosphere; Seismic Tomography; Solid Earth", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": null, "persons": "Hansen, Samantha", "project_titles": "New Approach to Investigate the Seismic Velocity Structure beneath Antarctica", "projects": [{"proj_uid": "p0000354", "repository": "USAP-DC", "title": "New Approach to Investigate the Seismic Velocity Structure beneath Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "A New Approach to Investigate the Seismic Velocity Structure beneath Antarctica", "uid": "600132", "west": -180.0}, {"awards": "0229245 Hamilton, Gordon; 0838843 Kurbatov, Andrei; 9527571 Whillans, Ian", "bounds_geometry": ["POLYGON((158.25 -76.66667,158.325 -76.66667,158.4 -76.66667,158.475 -76.66667,158.55 -76.66667,158.625 -76.66667,158.7 -76.66667,158.775 -76.66667,158.85 -76.66667,158.925 -76.66667,159 -76.66667,159 -76.683336,159 -76.700002,159 -76.716668,159 -76.733334,159 -76.75,159 -76.766666,159 -76.783332,159 -76.799998,159 -76.816664,159 -76.83333,158.925 -76.83333,158.85 -76.83333,158.775 -76.83333,158.7 -76.83333,158.625 -76.83333,158.55 -76.83333,158.475 -76.83333,158.4 -76.83333,158.325 -76.83333,158.25 -76.83333,158.25 -76.816664,158.25 -76.799998,158.25 -76.783332,158.25 -76.766666,158.25 -76.75,158.25 -76.733334,158.25 -76.716668,158.25 -76.700002,158.25 -76.683336,158.25 -76.66667))"], "date_created": "Tue, 20 Dec 2011 00:00:00 GMT", "description": "This data set includes includes high-precision GPS measurements of steel poles within the Allan Hills Main Ice Field, Near Western Ice Field, and extending to the eastern edge of the Middle Western Ice Field, in Antarctica. These data were collected between December 1997 and December 2010. The extended survey period allowed for vertical and horizontal velocities to be calculated with low associated error. Parameters include locations of poles in latitude and longitude, as well as elevation, ice velocity, and accumulation rates.\n\nData are available via FTP as ASCII text files in comma separated value (.csv) format. Raw data are also provided as Trimble raw data, compressed in .zip format, and supplementary information is provided in .csv format and portable document format (.pdf).", "east": 159.0, "geometry": ["POINT(158.625 -76.75)"], "keywords": "Allan Hills; Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity", "locations": "Antarctica; Allan Hills", "north": -76.66667, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Kurbatov, Andrei V.; Spikes, Vandy Blue; Hamilton, Gordon S.; Spaulding, Nicole", "project_titles": "GPS Measurements of Rock and Ice Motions in South Victoria Land", "projects": [{"proj_uid": "p0000523", "repository": "USAP-DC", "title": "GPS Measurements of Rock and Ice Motions in South Victoria Land"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.83333, "title": "GPS Ice Flow Measurements, Allan Hills, Antarctica", "uid": "609507", "west": 158.25}, {"awards": "0440847 Raymond, Charles", "bounds_geometry": ["POLYGON((-115.457 -78.7489,-114.8241 -78.7489,-114.1912 -78.7489,-113.5583 -78.7489,-112.9254 -78.7489,-112.2925 -78.7489,-111.6596 -78.7489,-111.0267 -78.7489,-110.3938 -78.7489,-109.7609 -78.7489,-109.128 -78.7489,-109.128 -78.83802,-109.128 -78.92714,-109.128 -79.01626,-109.128 -79.10538,-109.128 -79.1945,-109.128 -79.28362,-109.128 -79.37274,-109.128 -79.46186,-109.128 -79.55098,-109.128 -79.6401,-109.7609 -79.6401,-110.3938 -79.6401,-111.0267 -79.6401,-111.6596 -79.6401,-112.2925 -79.6401,-112.9254 -79.6401,-113.5583 -79.6401,-114.1912 -79.6401,-114.8241 -79.6401,-115.457 -79.6401,-115.457 -79.55098,-115.457 -79.46186,-115.457 -79.37274,-115.457 -79.28362,-115.457 -79.1945,-115.457 -79.10538,-115.457 -79.01626,-115.457 -78.92714,-115.457 -78.83802,-115.457 -78.7489))"], "date_created": "Thu, 01 Sep 2011 00:00:00 GMT", "description": "This data set includes ice flow velocities and strain configurations, from GPS measurements on the West Antarctic Ice Sheet (WAIS) Divide. Ninety markers installed in the firn were measured during two consecutive field seasons running from 2005-2006 and 2006-2007. The markers were located in 150 by 60 km area, with smaller clusters of five markers located within about 10 km of each other. Consecutive GPS measurements were used to derive velocity for each marker. Strain configurations were estimated by differentiating a linear fit of the data at each marker cluster. \n\nData are available via FTP as ASCII text (.txt ) files in comma separated value format.", "east": -109.128, "geometry": ["POINT(-112.2925 -79.1945)"], "keywords": "Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ice Flow Velocity; Ross-Amundsen Divide; Strain", "locations": "Antarctica; Ross-Amundsen Divide", "north": -78.7489, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Matsuoka, Kenichi; Power, Donovan; Rasmussen, Al", "project_titles": "Detection of Crystal Orientation Fabrics near the Ross/Amundsen Sea Ice-flow Divide and at the Siple Dome Ice Core Site using Polarimetric Radar Methods", "projects": [{"proj_uid": "p0000024", "repository": "USAP-DC", "title": "Detection of Crystal Orientation Fabrics near the Ross/Amundsen Sea Ice-flow Divide and at the Siple Dome Ice Core Site using Polarimetric Radar Methods"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.6401, "title": "GPS-Measured Ice Velocities and Strain Data from the Ross and Amundsen Sea Ice Flow Divide, West Antarctica", "uid": "609503", "west": -115.457}, {"awards": "0228052 Kreutz, Karl", "bounds_geometry": ["POLYGON((161.04 -77.3,161.239 -77.3,161.438 -77.3,161.637 -77.3,161.836 -77.3,162.035 -77.3,162.234 -77.3,162.433 -77.3,162.632 -77.3,162.831 -77.3,163.03 -77.3,163.03 -77.378,163.03 -77.456,163.03 -77.534,163.03 -77.612,163.03 -77.69,163.03 -77.768,163.03 -77.846,163.03 -77.924,163.03 -78.002,163.03 -78.08,162.831 -78.08,162.632 -78.08,162.433 -78.08,162.234 -78.08,162.035 -78.08,161.836 -78.08,161.637 -78.08,161.438 -78.08,161.239 -78.08,161.04 -78.08,161.04 -78.002,161.04 -77.924,161.04 -77.846,161.04 -77.768,161.04 -77.69,161.04 -77.612,161.04 -77.534,161.04 -77.456,161.04 -77.378,161.04 -77.3))"], "date_created": "Wed, 01 Jul 2009 00:00:00 GMT", "description": "This data set includes high-resolution ice core records from the Dry Valleys region of Antarctica, and provides interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). Intermediate-length ice cores (100 to 200 meters) were drilled at four sites along transects in the Taylor and Wright valleys, and analyzed for stable isotopes and major ions. The data set includes high-resolution ice core data for each study site. It also includes mass balance, borehole temperature, and snowpit data for each site, and Global Positioning System (GPS) velocity data for some of the sites. Snow pit data from three additional sites in the same region is also available. Data are available via FTP, in Microsoft Excel (.xls), ASCII text (.txt), and Microsoft Word (.doc) file formats.", "east": 163.03, "geometry": ["POINT(162.035 -77.69)"], "keywords": "Antarctica; Borehole Temperature; Chemistry:ice; Chemistry:Ice; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Mass Balance; Paleoclimate; Physical Properties", "locations": "Dry Valleys; Antarctica", "north": -77.3, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Kreutz, Karl; Mayewski, Paul A.", "project_titles": "Dry Valleys Late Holocene Climate Variability", "projects": [{"proj_uid": "p0000155", "repository": "USAP-DC", "title": "Dry Valleys Late Holocene Climate Variability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.08, "title": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "uid": "609399", "west": 161.04}, {"awards": "0229546 MacAyeal, Douglas", "bounds_geometry": ["POINT(-178 -78)"], "date_created": "Wed, 01 Oct 2008 00:00:00 GMT", "description": "In October 2005, three geodetic GPS receivers were deployed on the Ross Ice Shelf near the ice front to observe short-term fluctuations in ice-shelf velocity associated with tidal forcing and other phenomena. Two stations were placed on either side of a large rift that is expected to eventually create the next iceberg to calve from the Ross Ice Shelf (called \"Nascent Iceberg\"). One station was established at a location near station R13, occupied in 1979 during the RIGGS project (Thomas et al., 1984), to determine if the near-ice-front part of the Ross Ice Shelf has significantly changed its long-term flow since the late 1970s.", "east": -178.0, "geometry": ["POINT(-178 -78)"], "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; Ross Ice Shelf; Southern Ocean", "locations": "Antarctica; Southern Ocean; Ross Ice Shelf", "north": -78.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brunt, Kelly; King, Matthew; MacAyeal, Douglas", "project_titles": "Collaborative Research of Earth\u0027s Largest Icebergs", "projects": [{"proj_uid": "p0000117", "repository": "USAP-DC", "title": "Collaborative Research of Earth\u0027s Largest Icebergs"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Continuous GPS (static) Data from the Ross Ice Shelf, Antarctica", "uid": "609347", "west": -178.0}, {"awards": "0125579 Cuffey, Kurt", "bounds_geometry": ["POLYGON((160 -77.83333,160.3 -77.83333,160.6 -77.83333,160.9 -77.83333,161.2 -77.83333,161.5 -77.83333,161.8 -77.83333,162.1 -77.83333,162.4 -77.83333,162.7 -77.83333,163 -77.83333,163 -77.849997,163 -77.866664,163 -77.883331,163 -77.899998,163 -77.916665,163 -77.933332,163 -77.949999,163 -77.966666,163 -77.983333,163 -78,162.7 -78,162.4 -78,162.1 -78,161.8 -78,161.5 -78,161.2 -78,160.9 -78,160.6 -78,160.3 -78,160 -78,160 -77.983333,160 -77.966666,160 -77.949999,160 -77.933332,160 -77.916665,160 -77.899998,160 -77.883331,160 -77.866664,160 -77.849997,160 -77.83333))"], "date_created": "Sat, 01 Dec 2007 00:00:00 GMT", "description": "This data set contains surface velocities of Taylor Glacier, Antarctica, for the year 2003. Measurement period was approximately 12 months. There are approximately 250 locations in this data set.", "east": 163.0, "geometry": ["POINT(161.5 -77.916665)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Taylor Glacier", "locations": "Taylor Glacier; Antarctica", "north": -77.83333, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Cuffey, Kurt M.; Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah", "project_titles": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System", "projects": [{"proj_uid": "p0000084", "repository": "USAP-DC", "title": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Surface Velocities of Taylor Glacier, Antarctica", "uid": "609324", "west": 160.0}, {"awards": null, "bounds_geometry": null, "date_created": "Thu, 15 Jun 2006 00:00:00 GMT", "description": "CUB shear velocity model is created from a large data set of the surface wave fundamental model phase and group velocity measurements. Phase velocities in period range between 40 an 150 s are generously donated by Harvard University and Utrecht University. These phase velocity data sets are described by Ekstr\u00f6m et al. (1997) and Trampert and Woodhouse (1995). The group velocity measurements at periods between 16 and 200s are performed at the Center for Imaging the Earth\u0027s Interior in the University of Colorado at Boulder. The group velocities are measured with the frequency-time analysis (Levshin et al., 1989) in which for every waveform a human analyst defines the frequency range of measurements and separate the signal form a variety of noise sources (e.g., overtones, fundamental modes of different types, other earthquakes, multipaths, scattered arrivals). We used broadband waveforms following earthquakes occurred from 1997 to present and recorded at stations from both global networks (GDSN, GSN, GEOSCOPE) as well as temporary regional arrays. At present, the group velocity dataset is composed of about 200000 paths.\n\nData coverage is generally better for Rayleigh waves than for Love waves, is better at intermediate periods than at very short or very long periods, and is better in the northern than in the southern hemisphere. This heterogeneous data coverage is imposed by the distribution of seismic stations and earthquakes. Data coverage optimizes in Eurasia and is currently worst across Africa, the central Pacific, parts of the Indian Ocean, and Antarctica.", "east": null, "geometry": null, "keywords": null, "locations": null, "north": null, "nsf_funding_programs": null, "persons": "Ritzwoller, Michael", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": null, "title": "Upper Mantle Shear Velocity Model", "uid": "600004", "west": null}, {"awards": "0086997 Truffer, Martin", "bounds_geometry": ["POLYGON((-140.7 -83.2,-140.12 -83.2,-139.54 -83.2,-138.96 -83.2,-138.38 -83.2,-137.8 -83.2,-137.22 -83.2,-136.64 -83.2,-136.06 -83.2,-135.48 -83.2,-134.9 -83.2,-134.9 -83.27,-134.9 -83.34,-134.9 -83.41,-134.9 -83.48,-134.9 -83.55,-134.9 -83.62,-134.9 -83.69,-134.9 -83.76,-134.9 -83.83,-134.9 -83.9,-135.48 -83.9,-136.06 -83.9,-136.64 -83.9,-137.22 -83.9,-137.8 -83.9,-138.38 -83.9,-138.96 -83.9,-139.54 -83.9,-140.12 -83.9,-140.7 -83.9,-140.7 -83.83,-140.7 -83.76,-140.7 -83.69,-140.7 -83.62,-140.7 -83.55,-140.7 -83.48,-140.7 -83.41,-140.7 -83.34,-140.7 -83.27,-140.7 -83.2))"], "date_created": "Thu, 17 Mar 2005 00:00:00 GMT", "description": "This product, based on prior data collected under NSF-OPP grant 8716604 (Echelmeyer and Harrison) and NSF-OPP grant 9117911 (Harrison), includes ice velocity data between stations S17 and UpB on the Upper Whillans Ice Stream, Siple Coast, West Antarctica, from January 1994 to January 1995. Velocities were measured using a total station, a surveying instrument that combines a digital theodolite and an Electronic Distance Measuring (EDM) device to measure horizontal and vertical angles, slope, and horizontal and vertical distances. Data are in ASCII and Excel formats, and are available via FTP.", "east": -134.9, "geometry": ["POINT(-137.8 -83.55)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Siple Coast", "locations": "Antarctica; Siple Coast", "north": -83.2, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Truffer, Martin; Echelmeyer, Keith A.", "project_titles": "Margin Migration Rates and Margin Dynamics of the Siple Coast Ice Streams", "projects": [{"proj_uid": "p0000144", "repository": "USAP-DC", "title": "Margin Migration Rates and Margin Dynamics of the Siple Coast Ice Streams"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -83.9, "title": "Margin Migration Rates and Dynamics: Siple Coast Ice Streams", "uid": "609263", "west": -140.7}, {"awards": "XXXXXXX Palais, Julie", "bounds_geometry": ["POLYGON((-180 -50,-144 -50,-108 -50,-72 -50,-36 -50,0 -50,36 -50,72 -50,108 -50,144 -50,180 -50,180 -54,180 -58,180 -62,180 -66,180 -70,180 -74,180 -78,180 -82,180 -86,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -86,-180 -82,-180 -78,-180 -74,-180 -70,-180 -66,-180 -62,-180 -58,-180 -54,-180 -50))"], "date_created": "Tue, 23 Mar 2004 00:00:00 GMT", "description": "This compilation of recent ice velocity data of the Antarctic ice sheet is intended for use by the polar scientific community. The data are presented in tabular form (ASCII), containing latitude, longitude, speed, bearing, and error ranges. A metadata header describes the source of the data, the time of measurement, and gives details on measurement accuracy and precision. The tables are available for ftp transfer.\n\nWeb pages developed specifically for this data set provide detailed information for viewing and selecting the velocity data. These pages contain large satellite image maps (available as jpeg files). The data sets used to create these images were contributed by several investigators, generally from already published work. Both in situ and image-based methods are used.\n\nReferences for the data sets are included with the data tables. If you have well-characterized Antarctic ice velocity data you would like to contribute to this site, please contact teds@icehouse.colorado.edu. If you have any questions concerning the relevance of these data to your work please contact NSIDC User Services.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Sample/collection Description; Sample/Collection Description", "locations": "Antarctica; Antarctica", "north": -50.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Bindschadler, Robert; Raymond, Charles", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Antarctic Ice Velocity Data", "uid": "609070", "west": -180.0}, {"awards": "9909469 Scambos, Ted", "bounds_geometry": ["POLYGON((-158 -82.2,-155.63 -82.2,-153.26 -82.2,-150.89 -82.2,-148.52 -82.2,-146.15 -82.2,-143.78 -82.2,-141.41 -82.2,-139.04 -82.2,-136.67 -82.2,-134.3 -82.2,-134.3 -82.33,-134.3 -82.46,-134.3 -82.59,-134.3 -82.72,-134.3 -82.85,-134.3 -82.98,-134.3 -83.11,-134.3 -83.24,-134.3 -83.37,-134.3 -83.5,-136.67 -83.5,-139.04 -83.5,-141.41 -83.5,-143.78 -83.5,-146.15 -83.5,-148.52 -83.5,-150.89 -83.5,-153.26 -83.5,-155.63 -83.5,-158 -83.5,-158 -83.37,-158 -83.24,-158 -83.11,-158 -82.98,-158 -82.85,-158 -82.72,-158 -82.59,-158 -82.46,-158 -82.33,-158 -82.2))"], "date_created": "Fri, 01 Aug 2003 00:00:00 GMT", "description": "This data set includes ice motion and topography measurements that were taken by measuring movement and altitude of poles set in the West Antarctic Ice Shelf. The data was acquired by Global Positioning System (GPS) measurements of poles. The position of the poles was measured twice; once in 2000, and again in 2002. Movement of the poles in that time show the ice motion velocity and direction.\n GPS pole positions are given in latitude and longitude, and elevations are given in meters above the WGS1984 ellipsoid. The data are presented as tables in ASCII text files. Three maps of the area are included with the data tables.\n\nThe National Science Foundation (NSF) funded this work under grant number OPP-9909469.", "east": -134.3, "geometry": ["POINT(-146.15 -82.85)"], "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Kamb Ice Stream", "locations": "Antarctica; Kamb Ice Stream", "north": -82.2, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Scambos, Ted; Catania, Ginny; Conway, Howard; Gades, Anthony; Raymond, Charles", "project_titles": "Collaborative Research: History and Evolution of the Siple Coast Ice Stream System as Recorded by Former Shear-Margin Scars", "projects": [{"proj_uid": "p0000165", "repository": "USAP-DC", "title": "Collaborative Research: History and Evolution of the Siple Coast Ice Stream System as Recorded by Former Shear-Margin Scars"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -83.5, "title": "Ice Motion and Topography Near Margin Areas of Kamb Ice Stream, Antarctica", "uid": "609141", "west": -158.0}, {"awards": "0126286 McConnell, Joseph", "bounds_geometry": ["POINT(-149 -81)"], "date_created": "Wed, 14 May 2003 00:00:00 GMT", "description": "This data set is part of the WAISCORES project, an NSF-funded project to understand the influence of the West Antarctic ice sheet on climate and sea level change. WAISCORES researchers acquired and analyzed ice cores from the Siple Dome, in the Siple Coast region, West Antarctica.\n\nLamorey measured the density of the shallow Siple Dome cores B - I. One-meter sections of the ice core were weighed on a balance beam in the field. The volume was determined by measuring the diameter and length of the core. The data consists of tab-delimited text files of density measurements and a sonic velocity profile, and a .gif format density-versus-depth plot. Data are available via FTP.", "east": -149.0, "geometry": ["POINT(-149 -81)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Siple Dome; Siple Dome Ice Core; WAISCORES", "locations": "Siple Dome; Antarctica", "north": -81.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Lamorey, Gregg W.", "project_titles": "Continuous High Resolution Ice-Core Chemistry using ICP-MS at Siple Dome", "projects": [{"proj_uid": "p0000159", "repository": "USAP-DC", "title": "Continuous High Resolution Ice-Core Chemistry using ICP-MS at Siple Dome"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -81.0, "title": "Siple Shallow Core Density Data", "uid": "609129", "west": -149.0}, {"awards": "9318121 Anandakrishnan, Sridhar; 9222121 Dalziel, Ian", "bounds_geometry": ["POLYGON((-121.644 -82.2764,-121.4814 -82.2764,-121.3188 -82.2764,-121.1562 -82.2764,-120.9936 -82.2764,-120.831 -82.2764,-120.6684 -82.2764,-120.5058 -82.2764,-120.3432 -82.2764,-120.1806 -82.2764,-120.018 -82.2764,-120.018 -82.28496,-120.018 -82.29352,-120.018 -82.30208,-120.018 -82.31064,-120.018 -82.3192,-120.018 -82.32776,-120.018 -82.33632,-120.018 -82.34488,-120.018 -82.35344,-120.018 -82.362,-120.1806 -82.362,-120.3432 -82.362,-120.5058 -82.362,-120.6684 -82.362,-120.831 -82.362,-120.9936 -82.362,-121.1562 -82.362,-121.3188 -82.362,-121.4814 -82.362,-121.644 -82.362,-121.644 -82.35344,-121.644 -82.34488,-121.644 -82.33632,-121.644 -82.32776,-121.644 -82.3192,-121.644 -82.31064,-121.644 -82.30208,-121.644 -82.29352,-121.644 -82.28496,-121.644 -82.2764))", "POLYGON((-152.598 -81.8039,-149.8369 -81.8039,-147.0758 -81.8039,-144.3147 -81.8039,-141.5536 -81.8039,-138.7925 -81.8039,-136.0314 -81.8039,-133.2703 -81.8039,-130.5092 -81.8039,-127.7481 -81.8039,-124.987 -81.8039,-124.987 -81.90464,-124.987 -82.00538,-124.987 -82.10612,-124.987 -82.20686,-124.987 -82.3076,-124.987 -82.40834,-124.987 -82.50908,-124.987 -82.60982,-124.987 -82.71056,-124.987 -82.8113,-127.7481 -82.8113,-130.5092 -82.8113,-133.2703 -82.8113,-136.0314 -82.8113,-138.7925 -82.8113,-141.5536 -82.8113,-144.3147 -82.8113,-147.0758 -82.8113,-149.8369 -82.8113,-152.598 -82.8113,-152.598 -82.71056,-152.598 -82.60982,-152.598 -82.50908,-152.598 -82.40834,-152.598 -82.3076,-152.598 -82.20686,-152.598 -82.10612,-152.598 -82.00538,-152.598 -81.90464,-152.598 -81.8039))"], "date_created": "Sat, 01 Dec 2001 00:00:00 GMT", "description": "Ice velocity data from ice stream C, including the body of the ice stream and its area of onset, are available. The investigator calculated velocities from precise ice displacement measurements made with a geodetic-quality Global Positioning System (GPS). These ice displacement measurements accompanied seismic experiments aimed at understanding controls on the flow of ice streams in west Antarctica. An understanding of ice stream flow is essential to predicting the response of the West Antarctic Ice Sheet to future climate change.\n\nData are available in ASCII format via ftp.", "east": -120.018, "geometry": ["POINT(-120.831 -82.3192)", "POINT(-138.7925 -82.3076)"], "keywords": "Antarctica; Geodesy; Geology/Geophysics - Other; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS; WAIS", "locations": "Antarctica; WAIS", "north": -81.8039, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Anandakrishnan, Sridhar", "project_titles": "Microearthquake Monitoring of Ice Stream C, West Antarctica: A Sensor for Sticky Spots", "projects": [{"proj_uid": "p0000161", "repository": "USAP-DC", "title": "Microearthquake Monitoring of Ice Stream C, West Antarctica: A Sensor for Sticky Spots"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.8113, "title": "Ice Velocity Data from Ice Stream C, West Antarctica", "uid": "609106", "west": -152.598}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Thwaites Eastern Ice Shelf GPS displacements
|
1738992 1929991 |
2025-04-09 | Truffer, Martin; Scambos, Ted; Wild, Christian; Pettit, Erin; Alley, Karen |
NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment |
GPS data spanning two years (with data gaps) at the Cavity and Channel sites AMIGOS (Automated Meteorology-Ice-Geophysics Observing System) and a temporary nearby station (BOB) on the Thwaites Eastern Ice Shelf, Antarctica. Data are reported as processed positions (latitude/longitude/height above WGS84 ellipsoid) and derived along flow velocities. <br/> | ["POLYGON((-114 -74,-113 -74,-112 -74,-111 -74,-110 -74,-109 -74,-108 -74,-107 -74,-106 -74,-105 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105 -76,-106 -76,-107 -76,-108 -76,-109 -76,-110 -76,-111 -76,-112 -76,-113 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))"] | ["POINT(-109 -75)"] | false | false |
Sentinel-1-derived monthly-averaged velocity components from Thwaites Eastern Ice Shelf, 2016 - 2022
|
1929991 |
2025-03-11 | Banerjee, Debangshu; Lilien, David; Luckman, Adrian; Truffer, Martin; Wild, Christian; Pettit, Erin; Scambos, Ted; Muto, Atsuhiro; Alley, Karen |
NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment |
Monthly velocity composites were produced from January 2016 to December 2022 using Sentinel-1 Interferometric Wide Swath (IW) mode using standard feature/speckle tracking procedures. From 2016 to 2021, up to 10 mosaics per month were averaged (Sentinel 1A and Sentinel 1B). After Sentinel-1B ended in December 2021, mosaics decreased to 2 per month (12-day pairs only from Sentinel 1A), producing more noisy data and larger data gaps. We used 6- and 12-day Sentinel-1 image pairs from the archive and a feature tracking window of 416 × 128 pixels (∼1 km in range and azimuth). We sampled the velocity field at 50 × 10 pixels before geocoding to the Antarctic Polar Stereographic projection (EPSG:3031) at 100 m resolution using the REMA mosaic DEM. DEM gaps were filled using Bedmap2 surface topography data. | ["POLYGON((-106.5 -74.5,-106.3 -74.5,-106.1 -74.5,-105.9 -74.5,-105.7 -74.5,-105.5 -74.5,-105.3 -74.5,-105.1 -74.5,-104.9 -74.5,-104.7 -74.5,-104.5 -74.5,-104.5 -74.6,-104.5 -74.7,-104.5 -74.8,-104.5 -74.9,-104.5 -75,-104.5 -75.1,-104.5 -75.2,-104.5 -75.3,-104.5 -75.4,-104.5 -75.5,-104.7 -75.5,-104.9 -75.5,-105.1 -75.5,-105.3 -75.5,-105.5 -75.5,-105.7 -75.5,-105.9 -75.5,-106.1 -75.5,-106.3 -75.5,-106.5 -75.5,-106.5 -75.4,-106.5 -75.3,-106.5 -75.2,-106.5 -75.1,-106.5 -75,-106.5 -74.9,-106.5 -74.8,-106.5 -74.7,-106.5 -74.6,-106.5 -74.5))"] | ["POINT(-105.5 -75)"] | false | false |
Shear Wave Velocity of the Antarctic Upper Mantle from Full Waveform Inversion and Long Period Ambient Seismic Noise
|
1643873 1643798 |
2025-02-27 | Emry, Erica; Hansen, Samantha |
Collaborative Research: Imaging Seismic Heterogeneity within the Antarctic Mantle with Full Waveform Ambient Noise Tomography |
This dataset provides the shear-wave velocity model resulting from a full-waveform inversion that was constrained using long-period empirical Green's functions extracted from ambient seismic noise. The results are highlighted in Hansen and Emry (2025). | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Yearly velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2013-2022
|
1929991 |
2025-02-21 | Banerjee, Debangshu; Lilien, David; Truffer, Martin; Luckman, Adrian; Wild, Christian; Pettit, Erin; Scambos, Ted; Muto, Atsuhiro; Alley, Karen |
NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment |
This dataset comprises GeoTiff files that capture the yearly averages of ice-flow velocity (including x- and y-components, and flow speed) and strain rates (longitudinal, transverse, and shear) for the Thwaites Eastern Ice Shelf (TEIS) from 2013 to 2022. The velocity grids were generated using ITS_LIVE image-pair velocities available throughout the year, ensuring a consistent extent and spatial resolution for each annual composite. These composites were created by stacking all available image pairs and taking the median value for each grid cell. Small data gaps near the grounding line were filled using bilinear interpolation. Each pixel in the grid represents the median value of all available pixels during the specified period. The data are gridded at a spatial resolution of 120m in a polar stereographic projection (EPSG:3031). Speed is given in metres per day (m/yr), and strain rates are given in units/day. Additional funding was received from NE/S006419/1. | ["POLYGON((-106.5 -74.5,-106.3 -74.5,-106.1 -74.5,-105.9 -74.5,-105.7 -74.5,-105.5 -74.5,-105.3 -74.5,-105.1 -74.5,-104.9 -74.5,-104.7 -74.5,-104.5 -74.5,-104.5 -74.6,-104.5 -74.7,-104.5 -74.8,-104.5 -74.9,-104.5 -75,-104.5 -75.1,-104.5 -75.2,-104.5 -75.3,-104.5 -75.4,-104.5 -75.5,-104.7 -75.5,-104.9 -75.5,-105.1 -75.5,-105.3 -75.5,-105.5 -75.5,-105.7 -75.5,-105.9 -75.5,-106.1 -75.5,-106.3 -75.5,-106.5 -75.5,-106.5 -75.4,-106.5 -75.3,-106.5 -75.2,-106.5 -75.1,-106.5 -75,-106.5 -74.9,-106.5 -74.8,-106.5 -74.7,-106.5 -74.6,-106.5 -74.5))"] | ["POINT(-105.5 -75)"] | false | false |
Lithospheric thicknesses in Antarctica from Sp receiver functions
|
2201129 |
2025-02-12 | Brown, Sarah; Fischer, Karen |
Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity |
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 70–100 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˚E) and 90-130 km (~115˚E). Interpretation of these results and comparison with prior studies are provided in the associated journal article (see References). | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Crustal thicknesses in Antarctica from Sp receiver functions
|
2201129 |
2025-02-12 | Brown, Sarah; Fischer, Karen |
Probing the Western Antarctic Lithosphere and Asthenosphere with New Approaches to Imaging Seismic Wave Attenuation and Velocity |
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). | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Current velocity and direction data from Regional Ocean Modeling System simulations (2006-2007 & 2010-2011)
|
2138277 |
2024-05-09 | Gallagher, Katherine |
OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula |
This dataset includes daily-averaged current speed and velocity data from the Regional Ocean Modeling System. Domain covers the West Antarctic Peninsula. Simulations are from the 2006, 2007, 2010, and 2011 seasons. | ["POLYGON((-97.5 -55,-92.05 -55,-86.6 -55,-81.15 -55,-75.7 -55,-70.25 -55,-64.8 -55,-59.35 -55,-53.9 -55,-48.449999999999996 -55,-43 -55,-43 -57.1,-43 -59.2,-43 -61.3,-43 -63.4,-43 -65.5,-43 -67.6,-43 -69.7,-43 -71.8,-43 -73.9,-43 -76,-48.45 -76,-53.9 -76,-59.35 -76,-64.8 -76,-70.25 -76,-75.7 -76,-81.15 -76,-86.6 -76,-92.05000000000001 -76,-97.5 -76,-97.5 -73.9,-97.5 -71.8,-97.5 -69.7,-97.5 -67.6,-97.5 -65.5,-97.5 -63.4,-97.5 -61.3,-97.5 -59.2,-97.5 -57.099999999999994,-97.5 -55))"] | ["POINT(-70.25 -65.5)"] | false | false |
Hercules Dome ApRES Data
|
1744649 |
2023-10-09 | Hills, Benjamin; Holschuh, Nicholas; Hoffman, Andrew; Fudge, Tyler J; Horlings, Annika; Erwin, Emma; Steig, Eric J.; Christianson, Knut |
Ice Dynamics at the Intersection of the West and East Antarctic Ice Sheets |
Phase-sensitive radar data collected at Hercules Dome, Antarctica. These data are processed in two ways for two separate objectives. First, repeat acquisitions between years are interfered to interpret vertical velocity. Second, polarized acquisitions are interfered to interpret crystal orientation fabric. The full processing flow is included to recreate the given data products from the included raw data. | ["POLYGON((-110.338 -85.76,-109.5454 -85.76,-108.7528 -85.76,-107.9602 -85.76,-107.1676 -85.76,-106.375 -85.76,-105.5824 -85.76,-104.7898 -85.76,-103.9972 -85.76,-103.2046 -85.76,-102.412 -85.76,-102.412 -85.8266,-102.412 -85.89320000000001,-102.412 -85.9598,-102.412 -86.02640000000001,-102.412 -86.093,-102.412 -86.1596,-102.412 -86.2262,-102.412 -86.2928,-102.412 -86.35940000000001,-102.412 -86.426,-103.2046 -86.426,-103.9972 -86.426,-104.7898 -86.426,-105.5824 -86.426,-106.375 -86.426,-107.1676 -86.426,-107.9602 -86.426,-108.7528 -86.426,-109.5454 -86.426,-110.338 -86.426,-110.338 -86.35940000000001,-110.338 -86.2928,-110.338 -86.2262,-110.338 -86.1596,-110.338 -86.093,-110.338 -86.02640000000001,-110.338 -85.9598,-110.338 -85.89320000000001,-110.338 -85.8266,-110.338 -85.76))"] | ["POINT(-106.375 -86.093)"] | false | false |
AGASEA 4.7 ka Englacial Isochron over the Thwaites Glacier Catchment
|
1043761 0230197 2127606 0636724 |
2023-03-15 | Muldoon, Gail R.; Young, Duncan A.; Jackson, Charles; Blankenship, Donald D. |
Geophysical Investigations of Marie Byrd Land Lithospheric Evolution (GIMBLE) Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) Collaborative Research: Synthesis of Thwaites Glacier Dynamics: Diagnostic and Prognostic Sensitivity Studies of a West Antarctic Outlet System |
This file contains internal radar horizon 1 (lm-MERGE-lay9-grg) for West Antarctica, collected during the SOAR/CASERTZ (1991-1996), SOAR/DVD (1999), ATRS (2001), AGASEA (2004-05) and GIMBLE (2013-2014) expeditions. Only data collected in AGASEA is contained in this specific product. This data set is linked to PH.D thesis Muldoon, G. 2018 "West Antarctic Ice Sheet Retreat during the Last Interglacial"Spatial and temporal distributions of accumulation rates on the catchment of Thwaites Glacier, West Antarctica", University of Texas at Austin https://doi.org/10.15781/T23B5WS0D The internal radar horizon (IRH) was traced semi-automatically by Gail R. Muldoon using Haliburtons's Landmark software and picker, in a combination of 2D focused and unfocused data. Depths were calculated using a 2 way velocity in ice of 84.5 m/microsecond, and no firn correction. Isochron age is 4711 (+/- 246 ) years. Funding for this dataset as provided by NSF grants and The G. Unger Vetlesen Foundation. | ["POLYGON((-136 -74,-131.9 -74,-127.8 -74,-123.7 -74,-119.6 -74,-115.5 -74,-111.4 -74,-107.30000000000001 -74,-103.2 -74,-99.1 -74,-95 -74,-95 -74.7,-95 -75.4,-95 -76.1,-95 -76.8,-95 -77.5,-95 -78.2,-95 -78.9,-95 -79.6,-95 -80.3,-95 -81,-99.1 -81,-103.2 -81,-107.3 -81,-111.4 -81,-115.5 -81,-119.6 -81,-123.69999999999999 -81,-127.8 -81,-131.9 -81,-136 -81,-136 -80.3,-136 -79.6,-136 -78.9,-136 -78.2,-136 -77.5,-136 -76.8,-136 -76.1,-136 -75.4,-136 -74.7,-136 -74))"] | ["POINT(-115.5 -77.5)"] | false | false |
Current velocity and direction data from Regional Ocean Modeling System simulations (2008-2009 & 2018-2019)
|
2138277 |
2023-01-13 | Gallagher, Katherine |
OPP-PRF Pygoscelis Penguin Response to Potential Prey Retention along the West Antarctic Peninsula |
This dataset includes daily-averaged current speed and velocity data from the Regional Ocean Modeling System. Domain covers the West Antarctic Peninsula. Simulations are from the 2008, 2009, 2018, and 2019 seasons. | ["POLYGON((-97.5 -55,-92.05 -55,-86.6 -55,-81.15 -55,-75.7 -55,-70.25 -55,-64.8 -55,-59.35 -55,-53.9 -55,-48.449999999999996 -55,-43 -55,-43 -57.1,-43 -59.2,-43 -61.3,-43 -63.4,-43 -65.5,-43 -67.6,-43 -69.7,-43 -71.8,-43 -73.9,-43 -76,-48.45 -76,-53.9 -76,-59.35 -76,-64.8 -76,-70.25 -76,-75.7 -76,-81.15 -76,-86.6 -76,-92.05000000000001 -76,-97.5 -76,-97.5 -73.9,-97.5 -71.8,-97.5 -69.7,-97.5 -67.6,-97.5 -65.5,-97.5 -63.4,-97.5 -61.3,-97.5 -59.2,-97.5 -57.099999999999994,-97.5 -55))"] | ["POINT(-70.25 -65.5)"] | false | false |
South Pole Lake ApRES Radar
|
1643353 1744649 |
2022-01-06 | Hills, Benjamin |
Collaborative Research: Computational Methods Supporting Joint Seismic and Radar Inversion for Ice Fabric and Temperature in Streaming Flow |
These are ground-based radar data collected from a subglacial lake ~15 km from the geographic South Pole. Data were collected with the Autonomous phase-sensitive Radio Echo Sounder (ApRES) (Nicholls et al., 2015). The intention of this dataset is to be used for vertical velocity structure and interpretation. | ["POLYGON((-179.9989061 -89.752739299,-143.999017884 -89.752739299,-107.999129669 -89.752739299,-71.9992414529 -89.752739299,-35.9993532372 -89.752739299,0.000534978500013 -89.752739299,36.0004231942 -89.752739299,72.0003114099 -89.752739299,108.000199626 -89.752739299,144.000087841 -89.752739299,179.999976057 -89.752739299,179.999976057 -89.7772743702,179.999976057 -89.8018094414,179.999976057 -89.8263445126,179.999976057 -89.8508795838,179.999976057 -89.875414655,179.999976057 -89.8999497262,179.999976057 -89.9244847974,179.999976057 -89.9490198686,179.999976057 -89.9735549398,179.999976057 -89.998090011,144.000087841 -89.998090011,108.000199626 -89.998090011,72.0003114099 -89.998090011,36.0004231942 -89.998090011,0.000534978499985 -89.998090011,-35.9993532372 -89.998090011,-71.9992414529 -89.998090011,-107.999129669 -89.998090011,-143.999017884 -89.998090011,-179.9989061 -89.998090011,-179.9989061 -89.9735549398,-179.9989061 -89.9490198686,-179.9989061 -89.9244847974,-179.9989061 -89.8999497262,-179.9989061 -89.875414655,-179.9989061 -89.8508795838,-179.9989061 -89.8263445126,-179.9989061 -89.8018094414,-179.9989061 -89.7772743702,-179.9989061 -89.752739299))"] | ["POINT(0 -89.999)"] | false | false |
Dataset for Tidal modulation of ice streams: Effect of periodic sliding velocity on ice friction and healing
|
1245871 |
2021-12-23 | McCarthy, Christine M.; Skarbek, Rob; Savage, Heather |
Laboratory Study of Ice Deformation under Tidal Loading Conditions with Application to Antarctic Glaciers |
This data set contains text files for the experimental logs of ice-on-rock friction experiments that were conducted in a double direct shear apparatus at temperatures of -16.4 C to -2 C. There are eleven files (C28-C34, C39-C41, and C44). Each file contains 4 columns of data that correspond to time (s), vertical displacement (microns), friction, and velocity. The data were prepared by converting voltages from experimental feedbacks, to appropriate units using calibrations, as conducted separate. Miscellaneous loading and unloading data were removed and the data was filtered modestly (100 point moving average filter in matlab). The data set includes all information needed to plot friction or velocity vs. time or displacement from the beginning to end of the run. | [] | [] | false | false |
Circum-Antarctic grounding-line sinuosity
|
1246353 1745055 1745043 |
2021-11-10 | Simkins, Lauren; Stearns, Leigh; Riverman, Kiya |
Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum. Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations |
The dataset here allows exploration of the causes and significance of Antarctic grounding-line sinuosity by coupling observations of contemporary Antarctic grounding lines and paleo-grounding lines expressed as ice-marginal landforms on the Ross Sea continental shelf. Modern grounding lines are derived from the MEaSUREs Version 2 Differential Satellite Radar Interferometry dataset with spatial resolutions of 25-120 m spanning February 1992 to December 2014 (Rignot et al., 2016; Mouginot et al., 2017). The boundaries of individual grounding lines representative of individual glacial catchments (n=664) were delineated by the inflection points of the shear strain rate, εxy (c.f Van der Veen et al., 2011). Sinuosity was calculated as the ratio of the true length, orthogonal to ice-flow direction, of the grounding lines and the straight line length between end-points and in units of km/km. Raster data were extracted at 1-km points along each grounding line; the mean was calculated for each grounding line and merged in a table with sinuosity data. A dataset of 6,275 paleo-grounding lines expressed as ice-marginal landforms on the deglaciated western Ross Sea continental shelf are used in this study, originally published by Simkins et al., 2018. The ice-marginal landforms were mapped from multibeam echo sounder data that was collected onboard the RVIB Nathaniel B. Palmer (NBP) 15-02 cruise using a Kongsberg EM122 operating in dual swath mode at 12 kHz frequency with 30-60% swath overlap (Cruise DOI: 10.7284/901477). The resulting bathymetry data was gridded at 20-40 m with decimeter vertical elevation resolution depending on water depth and sea-state. Sinuosity is calculated as a ratio of true (mapped) landform length, measured in the across paleo-ice flow direction at the crest of the landform, to the straight line distance between the mapped landform endpoints and in units of km/km. To compare modern and paleo-grounding lines, we use a consistent length scale by segmenting the grounding lines into 2-km sections for the two datasets (modern, n=12,966; paleo, n=5,832), even though this eliminates grounding lines that are less than 2-km long and thus results in 1 modern and 3,873 paleo-grounding lines removed. The full-length and 2-km segmented groundings lines are provided as shapefiles "InSAR_groundinglines_full" and "InSAR_groundinglines_2km", the paleo-grounding lines are provided as shapefiles "RossSea_icemarginal_full" and "RossSea_icemarginal_2km", and points marking modern grounding lines retreat from repeat InSAR surveys are provided as shapefile "InSAR_retreat_points", all stored together in a geodatabase named "Antarctic_groundinglines.gbd". Additional grounding line metrics, including length, sinuosity, bed roughness, and bed slope for modern and paleo-grounding lines, and height-above-buoyancy gradient, ice-flow velocity, presence of pinning points and ice shelves are provided for modern grounding lines. The published dataset was compiled and analyzed in the article "Controls on circum-Antarctic grounding-line sinuosity " by Simkins, L.M., Stearns, L.A., and Riverman, K.L, which will be submitted to a peer-review journal in November 2021. References Mouginot, J., B. Scheuchl, and E. Rignot. 2017. MEaSUREs Antarctic Boundaries for IPY 2007-2009 from Satellite Radar, Version 2. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. Rignot, E., J. Mouginot, and B. Scheuchl. 2016. MEaSUREs Antarctic Grounding Line from Differential Satellite Radar Interferometry, Version 2. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. Simkins, L. M., Greenwood, S. L., & Anderson, J. B. (2018). Diagnosing ice sheet grounding line stability from landform morphology. The Cryosphere, 12(8), 2707-2726. Van der Veen, C. J., J. C. Plummer, & L. A. Stearns. (2011). Controls on the recent speed up of Jakobshavn Isbræ, West Greenland. Journal of Glaciology, 57(204), 770-782 | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Two-year velocity and strain-rate averages from the Thwaites Eastern Ice Shelf, 2001-2020
|
1738992 |
2021-10-11 | Alley, Karen; Wild, Christian; Scambos, Ted; Muto, Atsu; Pettit, Erin; Truffer, Martin; Wallin, Bruce; Klinger, Marin |
NSF-NERC: Thwaites-Amundsen Regional Survey and Network (TARSAN) Integrating Atmosphere-Ice-Ocean Processes affecting the Sub-Ice-Shelf Environment |
This dataset includes GeoTiffs of two-year averages of ice flow velocity (including x- and y-components and flow speed) and longitudinal, transverse, and shear strain rates for the Thwaites Eastern Ice Shelf (TEIS) from 2001-2020. The grids were derived from feature tracking on MODIS, Landsat-7, and Landsat-8 imagery. Each pixel in a grid represents the median value of a stack of all available pixels for each time period. Data are gridded at a 500 m spatial resolution in a polar stereographic (EPSG:3031) projection. Speed units are m/day and strain rates are in units of /day. In addition, we provide videos of each variable (excluding x- and y-velocity components) placed alongside a MODIS image of the same extent and from around the same time to provide context. In addition to the variables noted above, we include videos for flow direction (in degrees from grid north in an EPSG:3031 projection) and a zoomed-in version of flow direction, which were calculated from the provided grids. | ["POLYGON((-114 -74,-113 -74,-112 -74,-111 -74,-110 -74,-109 -74,-108 -74,-107 -74,-106 -74,-105 -74,-104 -74,-104 -74.2,-104 -74.4,-104 -74.6,-104 -74.8,-104 -75,-104 -75.2,-104 -75.4,-104 -75.6,-104 -75.8,-104 -76,-105 -76,-106 -76,-107 -76,-108 -76,-109 -76,-110 -76,-111 -76,-112 -76,-113 -76,-114 -76,-114 -75.8,-114 -75.6,-114 -75.4,-114 -75.2,-114 -75,-114 -74.8,-114 -74.6,-114 -74.4,-114 -74.2,-114 -74))"] | ["POINT(-109 -75)"] | false | false |
Rate-state friction parameters for ice-on-rock oscillation experiments
|
1245871 |
2021-07-30 | Skarbek, Rob; McCarthy, Christine M.; Savage, Heather |
Laboratory Study of Ice Deformation under Tidal Loading Conditions with Application to Antarctic Glaciers |
This data set contains rate and state frictional parameters for ice-on-rock friction experiments that were conducted in a double direct shear apparatus as temperatures of -16.4 C to -2 C. The frictional parameters were deteremined by directly fitting the frictional response to controlled, harmonic oscillations in load point velocity. The data set includes all information needed to reproduce the fits, as well as tables of the frictional parameters for both the aging and slip law forms of frictional state evolution. | [] | [] | false | false |
2D shear-wave velocity model across the West Antarctic Rift System from POLENET-ANET seismic data
|
1643795 |
2021-01-15 | Mikesell, Dylan |
Collaborative Research: Monitoring Antarctic Ice Sheet Changes with Ambient Seismic Noise Methods |
This data set includes observations of Rayleigh and Love wave group and phase velocity dispersion curves from ambient noise crosscorrelation functions. The data set includes the corresponding shear wave velocity model produced by joint inversion of these dispersion curves. This investigators developed a new crust and upper mantle model directly beneath the seismic stations used in this study. Data are in NetCDF and GeoCSV formats. The Python code used to generate the NetCDF files from the GeoCSV files is also contained in the data set. | ["POLYGON((-134.5 -75,-130.85 -75,-127.2 -75,-123.55 -75,-119.9 -75,-116.25 -75,-112.6 -75,-108.95 -75,-105.3 -75,-101.65 -75,-98 -75,-98 -75.85,-98 -76.7,-98 -77.55,-98 -78.4,-98 -79.25,-98 -80.1,-98 -80.95,-98 -81.8,-98 -82.65,-98 -83.5,-101.65 -83.5,-105.3 -83.5,-108.95 -83.5,-112.6 -83.5,-116.25 -83.5,-119.9 -83.5,-123.55 -83.5,-127.2 -83.5,-130.85 -83.5,-134.5 -83.5,-134.5 -82.65,-134.5 -81.8,-134.5 -80.95,-134.5 -80.1,-134.5 -79.25,-134.5 -78.4,-134.5 -77.55,-134.5 -76.7,-134.5 -75.85,-134.5 -75))"] | ["POINT(-116.25 -79.25)"] | false | false |
VELMAP
|
None | 2020-05-05 | Scambos, Ted | No project link provided | VELMAP is a compilation of ice velocity data of the Antarctic ice sheet and is intended for use by the polar scientific community. The data are presented in tabular form (ASCII format), containing latitude, longitude, speed, bearing, and error ranges. A metadata header describes the source of the data, the time of measurement, and gives details on measurement accuracy and precision. The data sets were contributed by several investigators, in most cases from already-published work. Both in situ and image-based methods are used. References for the data sets are included with the data tables. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1210
|
1043623 |
2020-05-01 | Miller, Scott; Butterworth, Brian |
Air-Sea Fluxes of Momentum, Heat, and Carbon Dioxide at High Wind Speeds in the Southern Ocean |
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 NBP1210 conducted in 2013. The files are of XLS format | ["POLYGON((-180 -57,-169.5 -57,-159 -57,-148.5 -57,-138 -57,-127.5 -57,-117 -57,-106.5 -57,-96 -57,-85.5 -57,-75 -57,-75 -59.1,-75 -61.2,-75 -63.3,-75 -65.4,-75 -67.5,-75 -69.6,-75 -71.7,-75 -73.8,-75 -75.9,-75 -78,-85.5 -78,-96 -78,-106.5 -78,-117 -78,-127.5 -78,-138 -78,-148.5 -78,-159 -78,-169.5 -78,180 -78,178.3 -78,176.6 -78,174.9 -78,173.2 -78,171.5 -78,169.8 -78,168.1 -78,166.4 -78,164.7 -78,163 -78,163 -75.9,163 -73.8,163 -71.7,163 -69.6,163 -67.5,163 -65.4,163 -63.3,163 -61.2,163 -59.1,163 -57,164.7 -57,166.4 -57,168.1 -57,169.8 -57,171.5 -57,173.2 -57,174.9 -57,176.6 -57,178.3 -57,-180 -57))"] | ["POINT(-136 -67.5)"] | false | false |
Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1402
|
1043623 |
2020-05-01 | Miller, Scott; Butterworth, Brian |
Air-Sea Fluxes of Momentum, Heat, and Carbon Dioxide at High Wind Speeds in the Southern Ocean |
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. | ["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))"] | ["POINT(131.75 -57.2)"] | false | false |
SPICEcore Advection
|
1443471 |
2020-03-25 | Fudge, T. J. |
Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core |
The South Pole Ice Core (SPICEcore), which spans the past 54,300 years, was drilled far from an ice divide such that ice recovered at depth originated upstream of the core site. If the climate is different upstream, the climate history recovered from the core will be a combination of the upstream conditions advected to the core site and temporal changes. Here, we evaluate the impact of ice advection on two fundamental records from SPICEcore: accumulation rate and water isotopes. We determined past locations of ice deposition based on GPS measurements of the modern velocity field spanning 100 km upstream, where ice of ~20 ka age would likely have originated. Beyond 100 km, there are no velocity measurements, but ice likely originates from Titan Dome, an additional 90 km distant. Shallow radar measurements extending 100 km upstream from the core site reveal large (~20%) variations in accumulation but no significant trend. Water isotope ratios, measured at 12.5 km intervals for the first 100 km of the flowline, show a decrease with elevation of -0.008‰ m-1 for δ18O. Advection adds approximately 1‰ for δ18O to the LGM-to-modern change. We also use an existing ensemble of continental ice-sheet model runs to assess the ice sheet elevation change through time. The magnitude of elevation change is likely small and the sign uncertain. Assuming a lapse rate of 10°C per km of elevation, the inference of LGM-to-modern temperature change is ~1.4°C smaller than if the flow from upstream is not considered. | ["POINT(-98.16 -89.99)"] | ["POINT(-98.16 -89.99)"] | false | false |
Investigating Ultra-low Velocity Zones (ULVZs) using an Antarctic Dataset
|
1643551 |
2020-03-10 | Hansen, Samantha; Carson, Sarah; Garnero, Edward; Yu, Shule; Rost, Sebastian |
Collaborative Research: Antarctic Seismic Investigations of ULVZ Structure |
Dataset includes information on all A- and B-ranked earthquakes (see Hansen et al., 2020) recorded by the Antarctic TAMNNET seismic array that were examined for ULVZ evidence. Information on their attenuation (t*) parameter, signal-to-noise ratio, core-mantle boundary bouncepoint location, and average remainder trace standard deviation are also provided. The provided figure indicates where ULVZ evidence has been found and where possible ULVZ evidence may be indicated. | [] | [] | false | false |
Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins
|
1148982 |
2019-07-31 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
The Transantarctic Mountains (TAMs) are the largest non-collisional mountain range on Earth. Their origin, as well as the origin of the Wilkes Subglacial Basin (WSB) along the inland side of the TAMs, have been widely debated, and a key constraint to distinguish between competing models is the underlying crustal structure. Previous investigations have examined this structure but have primarily focused on a small region of the central TAMs near Ross Island, providing little along-strike constraint. In this study, we use data from the new Transantarctic Mountains Northern Network and from five stations operated by the Korea Polar Research Institute to investigate the crustal structure beneath a previously unexplored portion of the TAMs. Using S-wave receiver functions and Rayleigh wave phase velocities, crustal thickness and average crustal shear velocity (Vs) are resolved within ±4 km and ±0.1 km/s, respectively. The crust thickens from ~20 km near the Ross Sea coast to ~46 km beneath the northern TAMs, which is somewhat thicker than that imaged in previous studies beneath the central TAMs. The crust thins to ~41 km beneath the WSB.Vs ranges from ~3.1-3.9 km/s, with slower velocities near the coast. Our findings are consistent with a flexural origin for the TAMs and WSB, where these features result from broad flexure of the East Antarctic lithosphere and uplift along its western edge due to thermal conduction from hotter mantle beneath West Antarctica. Locally thicker crust may explain the ~1 km of additional topography in the northern TAMs compared to the central TAMs. | ["POLYGON((150 -72,152 -72,154 -72,156 -72,158 -72,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,170 -72.3,170 -72.6,170 -72.9,170 -73.2,170 -73.5,170 -73.8,170 -74.1,170 -74.4,170 -74.7,170 -75,168 -75,166 -75,164 -75,162 -75,160 -75,158 -75,156 -75,154 -75,152 -75,150 -75,150 -74.7,150 -74.4,150 -74.1,150 -73.8,150 -73.5,150 -73.2,150 -72.9,150 -72.6,150 -72.3,150 -72))"] | ["POINT(160 -73.5)"] | false | false |
Tomographic PIV measurements of swimming shelled Antarctic pteropod
|
1246296 |
2018-07-26 | Adhikari, Deepak; Webster, Donald R; Yen, Jeannette |
Collaborative Research: Pteropod Swimming Behavior as a Bio Assay for Ocean Acidification |
A portable tomographic particle image velocimetry (tomographic PIV) system is described. The system was successfully deployed in Antarctica to study shelled Antarctic pteropods (Limacina helicina antarctica) – a delicate organism with an unusual propulsion mechanism. The experimental setup consists of a free-standing frame assembled with optical rails, thus avoiding the need for heavy and bulky equipment (e.g. an optical table). The cameras, lasers, optics, and tanks are all rigidly supported within the frame assembly. The results indicate that the pteropods flap their parapodia (or “wings”) downward during both power and recovery strokes, which is facilitated by the pitching of their shell. Shell pitching significantly alters the flapping trajectory, allowing the pteropod to move vertically and/or horizontally. The pronation and supination of the parapodia, together with the figure eight motion during flapping, suggest similarities with insect flight. The volumetric velocity field surrounding the freely-swimming pteropod reveals the generation of an attached vortex ring connecting the leading edge vortex to the trailing edge vortex during power stroke, and a presence of a leading-edge vortex during recovery stroke. These vortex structures play a major role in accelerating the organism vertically and indicate that forces generated on the parapodia during flapping constitute both lift and drag. After completing each stroke, two vortex rings are shed into the wake of the pteropod. The complex combination of body kinematics (parapodia flapping, shell pitch, saw-tooth trajectory), flow structures, and resulting force balance may be significantly altered by thinning of the pteropod shell, thus making pteropods an indicator of the detrimental effects of ocean acidification. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
McMurdo Ice Shelf GPS survey of vertical motion
|
1443126 |
2018-07-24 | MacAyeal, Douglas; Banwell, Alison |
Impact of Supraglacial Lakes on Ice-Shelf Stability |
Over 2 Austral summer periods in 2015/6 and 2016/17, up to 12 geodetic GPS receivers were deployed on the McMurdo Ice Shelf to study its vertical deflection in response to moving meltwater loads. (5 GPS were deployed in 2015/16, 12 in 2016/17.) The GPS receivers and antennas were supplied by UNAVCO and were Trimble NetR9’s and Zephyr Geodetic, respectively. The GPS receivers were stationary for the entire field seasons (were never moved). Following each field season, the GPS data were processed using MIT software called TRACK, which is part of the GAMIT package. The UNAVCO-run base station at McMurdo Station, approximately 16 km away from the field area, was used as part of the processing. | ["POLYGON((166.02819 -77.887495,166.053634 -77.887495,166.079078 -77.887495,166.104522 -77.887495,166.129966 -77.887495,166.15541 -77.887495,166.180854 -77.887495,166.206298 -77.887495,166.231742 -77.887495,166.257186 -77.887495,166.28263 -77.887495,166.28263 -77.8926145,166.28263 -77.897734,166.28263 -77.9028535,166.28263 -77.907973,166.28263 -77.9130925,166.28263 -77.918212,166.28263 -77.9233315,166.28263 -77.928451,166.28263 -77.9335705,166.28263 -77.93869,166.257186 -77.93869,166.231742 -77.93869,166.206298 -77.93869,166.180854 -77.93869,166.15541 -77.93869,166.129966 -77.93869,166.104522 -77.93869,166.079078 -77.93869,166.053634 -77.93869,166.02819 -77.93869,166.02819 -77.9335705,166.02819 -77.928451,166.02819 -77.9233315,166.02819 -77.918212,166.02819 -77.9130925,166.02819 -77.907973,166.02819 -77.9028535,166.02819 -77.897734,166.02819 -77.8926145,166.02819 -77.887495))"] | ["POINT(166.15541 -77.9130925)"] | false | false |
South Pole area GPS velocities
|
1443471 |
2018-05-29 | Lilien, David; Fudge, T. J.; Koutnik, Michelle; Conway, Howard; Waddington, Edwin D. |
Collaborative Research: Characterization of Upstream Ice and Firn Dynamics affecting the South Pole Ice Core |
These data indicate the positions and velocities of a network of stakes emplaced in the vicinity of South Pole during 2015-2018. They were collected by resurveying emplaced poles over the course of 1-2 years. | ["POLYGON((110 -89,117 -89,124 -89,131 -89,138 -89,145 -89,152 -89,159 -89,166 -89,173 -89,180 -89,180 -89.1,180 -89.2,180 -89.3,180 -89.4,180 -89.5,180 -89.6,180 -89.7,180 -89.8,180 -89.9,180 -90,173 -90,166 -90,159 -90,152 -90,145 -90,138 -90,131 -90,124 -90,117 -90,110 -90,110 -89.9,110 -89.8,110 -89.7,110 -89.6,110 -89.5,110 -89.4,110 -89.3,110 -89.2,110 -89.1,110 -89))"] | ["POINT(145 -89.5)"] | false | false |
Ross Sea unconformities digital grids in depth and two-way time
|
1341585 |
2018-05-25 | Sorlien, Christopher; Wilson, Douglas S. |
Subsidence, Tilting, Sedimentation, and Oligocene-middle Miocene paleo-depth of Ross Sea |
This data set includes digital 1 km grids of sub-bottom stratigraphy of most of Ross Sea. In addition to acoustic basement (same as top syn-rift sedimentary rocks in Central Trough and probably other basins), these grids include Oligocene and Miocene horizons that are unconformities in most areas. A sea floor grid is also included. Except for the sea floor grid, the grids are trimmed to be relatively close to control of interpreted seismic stratigraphy. The grids are provided in two way travel time and in depth. Math can be performed on the corresponding time and depth grids to recreate the 3D interval velocity model that was used. The velocity of the water used was 1450 m/s. More detailed descriptions of the work are found in the Final NSF report for PLR1341585 by C. Sorlien, B. Luyendyk, and D. Wilson. The grids are continuous so are merged with the sea floor where there is outcrop, or with basement if there is onlap, or with a young unconformity where there is sub-bottom truncation. The filenames include the name of the horizon (unconformity) and whether they are in time or depth. \"etc.\" means there are two or more horizons that have been merged. Most of the horizons are named and defined in the ANTOSTRAT (1995) atlas. The starting points for many of these horizons are ANTOSTRAT [1995] near DSDP sites 273, 272, and 270. In other areas we deviate from the interpretation of ANTOSTRAT [1995]. late Oligocene through middle Miocene horizons, interpreted very close to the ANTOSTRAT [1995] at DSDP Site 273 in Central Trough, are much deeper in our interpretation within Terror Rift. These horizon grids usually include the sea floor where there is outcrop or acoustic basement (top syn-rift in some basins) where there is onlap. ANTOSTRAT (1995), Seismic Stratigraphic Atlas of the Ross Sea, in Geology and Seismic Stratigraphy of the Antarctic Margin, edited by A. K. Cooper, Barker, P. F., Brancolini, G., 22 plates, American Geophysical Union, Washington, D.C. | ["POLYGON((-180 -73.22,-179.17 -73.22,-178.34 -73.22,-177.51 -73.22,-176.68 -73.22,-175.85 -73.22,-175.02 -73.22,-174.19 -73.22,-173.36 -73.22,-172.53 -73.22,-171.7 -73.22,-171.7 -73.765,-171.7 -74.31,-171.7 -74.855,-171.7 -75.4,-171.7 -75.945,-171.7 -76.49,-171.7 -77.035,-171.7 -77.58,-171.7 -78.125,-171.7 -78.67,-172.53 -78.67,-173.36 -78.67,-174.19 -78.67,-175.02 -78.67,-175.85 -78.67,-176.68 -78.67,-177.51 -78.67,-178.34 -78.67,-179.17 -78.67,180 -78.67,178.56 -78.67,177.12 -78.67,175.68 -78.67,174.24 -78.67,172.8 -78.67,171.36 -78.67,169.92 -78.67,168.48 -78.67,167.04 -78.67,165.6 -78.67,165.6 -78.125,165.6 -77.58,165.6 -77.035,165.6 -76.49,165.6 -75.945,165.6 -75.4,165.6 -74.855,165.6 -74.31,165.6 -73.765,165.6 -73.22,167.04 -73.22,168.48 -73.22,169.92 -73.22,171.36 -73.22,172.8 -73.22,174.24 -73.22,175.68 -73.22,177.12 -73.22,178.56 -73.22,-180 -73.22))"] | ["POINT(176.95 -75.945)"] | false | false |
Roosevelt Island: Radar and GPS
|
0944307 |
2017-11-16 | Conway, Howard |
Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island |
Ground-based radar data include radar echograms and .mat files of internal stratigraphy. Also included are picks of ice thickness and surface elevation. <br> GPS data include positions of 142 poles set in 2010 and resurveyed in 2012. Also given are velocity vectors for the poles. | ["POLYGON((-162.83 -79.15,-162.637 -79.15,-162.444 -79.15,-162.251 -79.15,-162.058 -79.15,-161.865 -79.15,-161.672 -79.15,-161.479 -79.15,-161.286 -79.15,-161.093 -79.15,-160.9 -79.15,-160.9 -79.1885037,-160.9 -79.2270074,-160.9 -79.2655111,-160.9 -79.3040148,-160.9 -79.3425185,-160.9 -79.3810222,-160.9 -79.4195259,-160.9 -79.4580296,-160.9 -79.4965333,-160.9 -79.535037,-161.093 -79.535037,-161.286 -79.535037,-161.479 -79.535037,-161.672 -79.535037,-161.865 -79.535037,-162.058 -79.535037,-162.251 -79.535037,-162.444 -79.535037,-162.637 -79.535037,-162.83 -79.535037,-162.83 -79.4965333,-162.83 -79.4580296,-162.83 -79.4195259,-162.83 -79.3810222,-162.83 -79.3425185,-162.83 -79.3040148,-162.83 -79.2655111,-162.83 -79.2270074,-162.83 -79.1885037,-162.83 -79.15))"] | ["POINT(-161.865 -79.3425185)"] | false | false |
Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains
|
1148982 |
2017-04-20 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
Using data from the Transantarctic Mountains (TAMs) Northern Network, the shear wave velocity structure beneath the northern TAMs was investigated with surface wave tomography. Rayleigh wave phase velocities were calculated using a two-plane wave approximation and were then inverted for shear velocity structure. The resulting model shows a low velocity zone (~4.24 km/s) at ~160 km depth offshore and adjacent to Mt. Melbourne that extends inland and vertically upwards to ~100 km depth beneath the northern TAMs and Victoria Land. Another low velocity zone (~4.16-4.24 km/s) is also seen at ~150 km depth beneath Ross Island, and relatively slow velocities (~4.24-4.32 km/s) along the Terror Rift connect the two low velocity zones. This structure has been interpreted to reflect rift-related decompression melting along the TAMs front, which would provide thermal buoyancy to uplift the mountain range. | ["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))"] | ["POINT(159.223506 -74.6349495)"] | false | false |
Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography
|
1148982 |
2017-04-06 | Hansen, Samantha |
CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin |
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' 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 ≥ 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; δVP ≈ -2.0%; δVS ≈ -1.5% to -4.0%) and Terra Nova Bay (TNB; δVP ≈ -1.5% to -2.0%; δVS ≈ -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 (δVP ≈ 0.5% to 2%; δVS ≈ 1.5% to 4.0%). A low velocity region (δVP ≈ -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. | ["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))"] | ["POINT(159.223506 -74.6349495)"] | false | false |
King George and Livingston Islands: Velocities and Digital Elevation Model
|
1043649 |
2016-02-17 | Osmanoglu, Batuhan; Hock, Regine |
Contribution of Western Antarctic Peninsula glaciers to sea level rise: Separation of the dynamic and climatic components |
The data contain the time series totals of SAR derived detrended surface velocities from Livingston Island, as well as GeoTiff files generated from intensity tracking of Synthetic Aperture Radar (SAR) imagery. The images include average annual velocity and ice thickness of King George Island, and average annual velocity, ice thickness, and a digital elevation model of Livingston Island. | ["POINT(-61 -62.75)", "POINT(-57.5 -61.75)"] | ["POINT(-61 -62.75)", "POINT(-57.5 -61.75)"] | false | false |
Tomographic Imaging of the Velocity and Magnetic Fields in the Sun's Atmosphere
|
0632399 |
2016-01-01 | Jefferies, Stuart M. |
Tomographic Imaging of the Velocity and Magnetic Fields in the Sun's Atmosphere |
The ultimate goal of this project is to determine the structure and dynamics of the Sun's atmosphere, assess the role of MHD waves in heating the chromosphere/corona and driving the solar wind, and better understand how the Sun's atmosphere couples to the solar interior. As the solar atmosphere is 'home' to many of the solar phenomena that can have a direct impact on the biosphere, including flares, coronal mass ejections, and the solar wind, the broader impact of such studies is that they will lead to an improved understanding of the Sun-Earth connection. Under the current award we have developed a suite of instruments that can simultaneously image the line-of-sight Doppler velocity and longitudinal magnetic field at four heights in the solar atmosphere at high temporal cadence. The instruments use magneto-optical filters (see Cacciani, Moretti and Rodgers, Solar Physics 174, p.115, 2004) tuned to the solar absorption lines at 422 nm (Ca I), 589 nm (Na D2), 770 nm (K) and 1083 nm (He). These lines sample the solar atmosphere from the mid-photosphere to the high-chromosphere. A proof-of-concept run was made in the Austral summer of 2007/2008 using the Na and K versions of the instruments. Here we recorded over 40 hours of full-disk, intensity images of the Sun in the red and blue wings of the Na and K Fraunhofer lines, in both right- and left-circularly polarized light. The images were obtained at a rate of one every five seconds with a nominal spatial resolution of 4 arc-seconds. The run started at 09:44 UT on February 2, 2008 and ended at 03:30 UT on February 4, 2008. Data Quality Assessment: The temperature controls of the instrument housings were unable to fully compensate for the harse Antartic winds encountered during the observing run. This led to large (~15 C) temperature swings which adversely affected the instruments (and thus data quality) in two ways: 1) Crystals of Na and K were deposited on the magneto-optical filter windows leading to "hot spots" in the images. These "hot spots" come and go with time as the temperature changes. 2) The changing temperature caused the optical rails to contract and expand causing the final images to go in- and out-of-focus, thus reducing the resolution to greater than 4 arc-seconds. Both these effect are worse in the K data. Despite these problems, the intensity images can be combined to provide magnetic images that show a very high sensitivity (< 5 Gauss in a 5 second integration). Data Description: The raw data are stored as a series of 1024x1024x4 FITS images. The format is: blue image (left circulary polarized light), blue image (right circularly polarized light), red image (left circulary polarized light), red image (right circularly polarized light). The naming convention for the images is: Type_Instrument_Day_hour_minutes_seconds where Type is I (intensity), F (flatfield), D (dark) Instrument is 0 (Na), 1 (K) Day is the day number from the beginning of the year where January 1 is day 0 For example, I_0_32_12_34_40.fits is an intensity image taken with the Na instrument at 12:34.40 UT on February 2, 2008. Notes: 1) The flatfield images were acquired by moving a diffuser in front of the Sun during the integration. The resulting images therefore have to be corrected for residual low-spatial frequencies due to the non-flat nature of the light source. 2) Each FITS file header contains a variety of information on the observation, e.g., F_CNTO : number of summed frames in each 5 second integration (*) FPS : Camera frame rate (Frames Per Second) FLIP : Rate at which the half-wave rotator (magnetic switch) was switched INT_PER : Integration time (in seconds) MOF : Temperature of magneto-optical filter cell WS : Temperature of wing selector cell TEMP_0 : Temperature of camera 0 TEMP_1 : Temperature of camera 1 TEMP_2 : Temperature inside instrument (location 1) TEMP_3 : Temperature of narrowband filter TEMP_5 : Temperature of magnets surrounding MOF cell TEMP_6 : Temperature inside instrument (location 2) TEMP_7 : Temperature of housing for magnetic switch (*) This is the frame count for the camera. The number of frames in each image for the two different polarization states, is half this number. The measured temperatures are only coarse measurements. 3) Due to reflection in the final polarizing beam splitter (which separates the "red" and "blue" signals into the two cameras), the camera 1 data need to "reversed" along the x-axis (i.e. listed as [1024:1] instead of [1:1024]) 4) Line-of-sight velocity and magnetic field images are generated from the observed intensity images. Doppler images as (red-blue)/(red+blue), magnetic images as the difference between the Doppler images for right- and left-circularly polarized light. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
Whillans Ice Stream Stick-slip
|
0944794 |
2015-09-17 | Wiens, Douglas; Winberry, Paul; Anandakrishnan, Sridhar; Alley, Richard |
Collaborative Research: Geophysical Study of Ice Stream Stick-slip Dynamics |
These data contain ice velocity measurements obtained from seismic and GPS recordings during the 2010 and 2011 Antarctic field seasons. | ["POLYGON((-165 -83.75,-164 -83.75,-163 -83.75,-162 -83.75,-161 -83.75,-160 -83.75,-159 -83.75,-158 -83.75,-157 -83.75,-156 -83.75,-155 -83.75,-155 -83.85,-155 -83.95,-155 -84.05,-155 -84.15,-155 -84.25,-155 -84.35,-155 -84.45,-155 -84.55,-155 -84.65,-155 -84.75,-156 -84.75,-157 -84.75,-158 -84.75,-159 -84.75,-160 -84.75,-161 -84.75,-162 -84.75,-163 -84.75,-164 -84.75,-165 -84.75,-165 -84.65,-165 -84.55,-165 -84.45,-165 -84.35,-165 -84.25,-165 -84.15,-165 -84.05,-165 -83.95,-165 -83.85,-165 -83.75))"] | ["POINT(-160 -84.25)"] | false | false |
Interaction of Ice Stream Flow with Heterogeneous Beds
|
0838811 |
2014-04-14 | Sergienko, Olga |
Model Investigation of Ice Stream/Subglacial Lake Systems |
This data set consists of outputs of several numerical models simulating ice stream flow over undulated bed, interaction of ice stream flow, and subglacial and supraglacial hydraulic systems. All simulations are performed for idealized geometries using finite-element models. | ["POINT(0 -78)"] | ["POINT(0 -78)"] | false | false |
A New Approach to Investigate the Seismic Velocity Structure beneath Antarctica
|
1139739 |
2014-01-01 | Hansen, Samantha |
New Approach to Investigate the Seismic Velocity Structure beneath Antarctica |
Intellectual Merit: Numerous candidate models for the geologic processes that have shaped the Antarctic continent have been proposed. To discriminate between them, detailed images of the upper mantle structure are required; however, the only existing continental-scale images of seismic structure beneath Antarctica lack sufficient resolution to delineate important, diagnostic features. Using newly available data from various Antarctic seismic networks, the PI will employ the adaptively parameterized tomography method to develop a high-resolution, continental-scale seismic velocity model for all of Antarctica. The proposed tomography method combines regional seismic travel-time datasets in the context of a global model to create a composite continental-scale model of upper mantle structure. The proposed method allows for imaging of finer structure in areas with better seismic ray coverage while simultaneously limiting the resolution of features in regions with less coverage. This research will help advance understanding of important global processes, such as craton formation, mountain building, continental rifting and associated magmatism. Additionally, the proposed research will have important impacts on other fields of Antarctic science. Constraints provided by tomographic results can be used to develop thermal models of the lithosphere needed to characterize the history and dynamics of ice sheets. Also, further constraints on lithospheric structure are required by climate-ice models, which are focused on understanding the cooling history of the Antarctic continent. Broader impacts: The PI is a new faculty member at the University of Alabama after having been funded as a National Science Foundation Postdoctoral Fellow in Polar Regions Research. The graduate student supported by this project is new to polar research. Through the UA-Tuscaloosa Magnet School partnership program, the PI will educate K-12 students about the Antarctic environment and associated career opportunities through various online and hands-on activities. University of Alabama dedicates a significant percentage of its enrollment space to underrepresented groups. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
GPS Ice Flow Measurements, Allan Hills, Antarctica
|
0229245 0838843 9527571 |
2011-12-20 | Kurbatov, Andrei V.; Spikes, Vandy Blue; Hamilton, Gordon S.; Spaulding, Nicole |
GPS Measurements of Rock and Ice Motions in South Victoria Land |
This data set includes includes high-precision GPS measurements of steel poles within the Allan Hills Main Ice Field, Near Western Ice Field, and extending to the eastern edge of the Middle Western Ice Field, in Antarctica. These data were collected between December 1997 and December 2010. The extended survey period allowed for vertical and horizontal velocities to be calculated with low associated error. Parameters include locations of poles in latitude and longitude, as well as elevation, ice velocity, and accumulation rates. Data are available via FTP as ASCII text files in comma separated value (.csv) format. Raw data are also provided as Trimble raw data, compressed in .zip format, and supplementary information is provided in .csv format and portable document format (.pdf). | ["POLYGON((158.25 -76.66667,158.325 -76.66667,158.4 -76.66667,158.475 -76.66667,158.55 -76.66667,158.625 -76.66667,158.7 -76.66667,158.775 -76.66667,158.85 -76.66667,158.925 -76.66667,159 -76.66667,159 -76.683336,159 -76.700002,159 -76.716668,159 -76.733334,159 -76.75,159 -76.766666,159 -76.783332,159 -76.799998,159 -76.816664,159 -76.83333,158.925 -76.83333,158.85 -76.83333,158.775 -76.83333,158.7 -76.83333,158.625 -76.83333,158.55 -76.83333,158.475 -76.83333,158.4 -76.83333,158.325 -76.83333,158.25 -76.83333,158.25 -76.816664,158.25 -76.799998,158.25 -76.783332,158.25 -76.766666,158.25 -76.75,158.25 -76.733334,158.25 -76.716668,158.25 -76.700002,158.25 -76.683336,158.25 -76.66667))"] | ["POINT(158.625 -76.75)"] | false | false |
GPS-Measured Ice Velocities and Strain Data from the Ross and Amundsen Sea Ice Flow Divide, West Antarctica
|
0440847 |
2011-09-01 | Matsuoka, Kenichi; Power, Donovan; Rasmussen, Al |
Detection of Crystal Orientation Fabrics near the Ross/Amundsen Sea Ice-flow Divide and at the Siple Dome Ice Core Site using Polarimetric Radar Methods |
This data set includes ice flow velocities and strain configurations, from GPS measurements on the West Antarctic Ice Sheet (WAIS) Divide. Ninety markers installed in the firn were measured during two consecutive field seasons running from 2005-2006 and 2006-2007. The markers were located in 150 by 60 km area, with smaller clusters of five markers located within about 10 km of each other. Consecutive GPS measurements were used to derive velocity for each marker. Strain configurations were estimated by differentiating a linear fit of the data at each marker cluster. Data are available via FTP as ASCII text (.txt ) files in comma separated value format. | ["POLYGON((-115.457 -78.7489,-114.8241 -78.7489,-114.1912 -78.7489,-113.5583 -78.7489,-112.9254 -78.7489,-112.2925 -78.7489,-111.6596 -78.7489,-111.0267 -78.7489,-110.3938 -78.7489,-109.7609 -78.7489,-109.128 -78.7489,-109.128 -78.83802,-109.128 -78.92714,-109.128 -79.01626,-109.128 -79.10538,-109.128 -79.1945,-109.128 -79.28362,-109.128 -79.37274,-109.128 -79.46186,-109.128 -79.55098,-109.128 -79.6401,-109.7609 -79.6401,-110.3938 -79.6401,-111.0267 -79.6401,-111.6596 -79.6401,-112.2925 -79.6401,-112.9254 -79.6401,-113.5583 -79.6401,-114.1912 -79.6401,-114.8241 -79.6401,-115.457 -79.6401,-115.457 -79.55098,-115.457 -79.46186,-115.457 -79.37274,-115.457 -79.28362,-115.457 -79.1945,-115.457 -79.10538,-115.457 -79.01626,-115.457 -78.92714,-115.457 -78.83802,-115.457 -78.7489))"] | ["POINT(-112.2925 -79.1945)"] | false | false |
Late Holocene Climate Variability, Dry Valleys, Antarctica
|
0228052 |
2009-07-01 | Kreutz, Karl; Mayewski, Paul A. |
Dry Valleys Late Holocene Climate Variability |
This data set includes high-resolution ice core records from the Dry Valleys region of Antarctica, and provides interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). Intermediate-length ice cores (100 to 200 meters) were drilled at four sites along transects in the Taylor and Wright valleys, and analyzed for stable isotopes and major ions. The data set includes high-resolution ice core data for each study site. It also includes mass balance, borehole temperature, and snowpit data for each site, and Global Positioning System (GPS) velocity data for some of the sites. Snow pit data from three additional sites in the same region is also available. Data are available via FTP, in Microsoft Excel (.xls), ASCII text (.txt), and Microsoft Word (.doc) file formats. | ["POLYGON((161.04 -77.3,161.239 -77.3,161.438 -77.3,161.637 -77.3,161.836 -77.3,162.035 -77.3,162.234 -77.3,162.433 -77.3,162.632 -77.3,162.831 -77.3,163.03 -77.3,163.03 -77.378,163.03 -77.456,163.03 -77.534,163.03 -77.612,163.03 -77.69,163.03 -77.768,163.03 -77.846,163.03 -77.924,163.03 -78.002,163.03 -78.08,162.831 -78.08,162.632 -78.08,162.433 -78.08,162.234 -78.08,162.035 -78.08,161.836 -78.08,161.637 -78.08,161.438 -78.08,161.239 -78.08,161.04 -78.08,161.04 -78.002,161.04 -77.924,161.04 -77.846,161.04 -77.768,161.04 -77.69,161.04 -77.612,161.04 -77.534,161.04 -77.456,161.04 -77.378,161.04 -77.3))"] | ["POINT(162.035 -77.69)"] | false | false |
Continuous GPS (static) Data from the Ross Ice Shelf, Antarctica
|
0229546 |
2008-10-01 | Brunt, Kelly; King, Matthew; MacAyeal, Douglas |
Collaborative Research of Earth's Largest Icebergs |
In October 2005, three geodetic GPS receivers were deployed on the Ross Ice Shelf near the ice front to observe short-term fluctuations in ice-shelf velocity associated with tidal forcing and other phenomena. Two stations were placed on either side of a large rift that is expected to eventually create the next iceberg to calve from the Ross Ice Shelf (called "Nascent Iceberg"). One station was established at a location near station R13, occupied in 1979 during the RIGGS project (Thomas et al., 1984), to determine if the near-ice-front part of the Ross Ice Shelf has significantly changed its long-term flow since the late 1970s. | ["POINT(-178 -78)"] | ["POINT(-178 -78)"] | false | false |
Surface Velocities of Taylor Glacier, Antarctica
|
0125579 |
2007-12-01 | Cuffey, Kurt M.; Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah |
Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System |
This data set contains surface velocities of Taylor Glacier, Antarctica, for the year 2003. Measurement period was approximately 12 months. There are approximately 250 locations in this data set. | ["POLYGON((160 -77.83333,160.3 -77.83333,160.6 -77.83333,160.9 -77.83333,161.2 -77.83333,161.5 -77.83333,161.8 -77.83333,162.1 -77.83333,162.4 -77.83333,162.7 -77.83333,163 -77.83333,163 -77.849997,163 -77.866664,163 -77.883331,163 -77.899998,163 -77.916665,163 -77.933332,163 -77.949999,163 -77.966666,163 -77.983333,163 -78,162.7 -78,162.4 -78,162.1 -78,161.8 -78,161.5 -78,161.2 -78,160.9 -78,160.6 -78,160.3 -78,160 -78,160 -77.983333,160 -77.966666,160 -77.949999,160 -77.933332,160 -77.916665,160 -77.899998,160 -77.883331,160 -77.866664,160 -77.849997,160 -77.83333))"] | ["POINT(161.5 -77.916665)"] | false | false |
Upper Mantle Shear Velocity Model
|
None | 2006-06-15 | Ritzwoller, Michael | No project link provided | CUB shear velocity model is created from a large data set of the surface wave fundamental model phase and group velocity measurements. Phase velocities in period range between 40 an 150 s are generously donated by Harvard University and Utrecht University. These phase velocity data sets are described by Ekström et al. (1997) and Trampert and Woodhouse (1995). The group velocity measurements at periods between 16 and 200s are performed at the Center for Imaging the Earth's Interior in the University of Colorado at Boulder. The group velocities are measured with the frequency-time analysis (Levshin et al., 1989) in which for every waveform a human analyst defines the frequency range of measurements and separate the signal form a variety of noise sources (e.g., overtones, fundamental modes of different types, other earthquakes, multipaths, scattered arrivals). We used broadband waveforms following earthquakes occurred from 1997 to present and recorded at stations from both global networks (GDSN, GSN, GEOSCOPE) as well as temporary regional arrays. At present, the group velocity dataset is composed of about 200000 paths. Data coverage is generally better for Rayleigh waves than for Love waves, is better at intermediate periods than at very short or very long periods, and is better in the northern than in the southern hemisphere. This heterogeneous data coverage is imposed by the distribution of seismic stations and earthquakes. Data coverage optimizes in Eurasia and is currently worst across Africa, the central Pacific, parts of the Indian Ocean, and Antarctica. | [] | [] | false | false |
Margin Migration Rates and Dynamics: Siple Coast Ice Streams
|
0086997 |
2005-03-17 | Truffer, Martin; Echelmeyer, Keith A. |
Margin Migration Rates and Margin Dynamics of the Siple Coast Ice Streams |
This product, based on prior data collected under NSF-OPP grant 8716604 (Echelmeyer and Harrison) and NSF-OPP grant 9117911 (Harrison), includes ice velocity data between stations S17 and UpB on the Upper Whillans Ice Stream, Siple Coast, West Antarctica, from January 1994 to January 1995. Velocities were measured using a total station, a surveying instrument that combines a digital theodolite and an Electronic Distance Measuring (EDM) device to measure horizontal and vertical angles, slope, and horizontal and vertical distances. Data are in ASCII and Excel formats, and are available via FTP. | ["POLYGON((-140.7 -83.2,-140.12 -83.2,-139.54 -83.2,-138.96 -83.2,-138.38 -83.2,-137.8 -83.2,-137.22 -83.2,-136.64 -83.2,-136.06 -83.2,-135.48 -83.2,-134.9 -83.2,-134.9 -83.27,-134.9 -83.34,-134.9 -83.41,-134.9 -83.48,-134.9 -83.55,-134.9 -83.62,-134.9 -83.69,-134.9 -83.76,-134.9 -83.83,-134.9 -83.9,-135.48 -83.9,-136.06 -83.9,-136.64 -83.9,-137.22 -83.9,-137.8 -83.9,-138.38 -83.9,-138.96 -83.9,-139.54 -83.9,-140.12 -83.9,-140.7 -83.9,-140.7 -83.83,-140.7 -83.76,-140.7 -83.69,-140.7 -83.62,-140.7 -83.55,-140.7 -83.48,-140.7 -83.41,-140.7 -83.34,-140.7 -83.27,-140.7 -83.2))"] | ["POINT(-137.8 -83.55)"] | false | false |
Antarctic Ice Velocity Data
|
None | 2004-03-23 | Bindschadler, Robert; Raymond, Charles | No project link provided | This compilation of recent ice velocity data of the Antarctic ice sheet is intended for use by the polar scientific community. The data are presented in tabular form (ASCII), containing latitude, longitude, speed, bearing, and error ranges. A metadata header describes the source of the data, the time of measurement, and gives details on measurement accuracy and precision. The tables are available for ftp transfer. Web pages developed specifically for this data set provide detailed information for viewing and selecting the velocity data. These pages contain large satellite image maps (available as jpeg files). The data sets used to create these images were contributed by several investigators, generally from already published work. Both in situ and image-based methods are used. References for the data sets are included with the data tables. If you have well-characterized Antarctic ice velocity data you would like to contribute to this site, please contact teds@icehouse.colorado.edu. If you have any questions concerning the relevance of these data to your work please contact NSIDC User Services. | ["POLYGON((-180 -50,-144 -50,-108 -50,-72 -50,-36 -50,0 -50,36 -50,72 -50,108 -50,144 -50,180 -50,180 -54,180 -58,180 -62,180 -66,180 -70,180 -74,180 -78,180 -82,180 -86,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -86,-180 -82,-180 -78,-180 -74,-180 -70,-180 -66,-180 -62,-180 -58,-180 -54,-180 -50))"] | ["POINT(0 -89.999)"] | false | false |
Ice Motion and Topography Near Margin Areas of Kamb Ice Stream, Antarctica
|
9909469 |
2003-08-01 | Scambos, Ted; Catania, Ginny; Conway, Howard; Gades, Anthony; Raymond, Charles |
Collaborative Research: History and Evolution of the Siple Coast Ice Stream System as Recorded by Former Shear-Margin Scars |
This data set includes ice motion and topography measurements that were taken by measuring movement and altitude of poles set in the West Antarctic Ice Shelf. The data was acquired by Global Positioning System (GPS) measurements of poles. The position of the poles was measured twice; once in 2000, and again in 2002. Movement of the poles in that time show the ice motion velocity and direction. GPS pole positions are given in latitude and longitude, and elevations are given in meters above the WGS1984 ellipsoid. The data are presented as tables in ASCII text files. Three maps of the area are included with the data tables. The National Science Foundation (NSF) funded this work under grant number OPP-9909469. | ["POLYGON((-158 -82.2,-155.63 -82.2,-153.26 -82.2,-150.89 -82.2,-148.52 -82.2,-146.15 -82.2,-143.78 -82.2,-141.41 -82.2,-139.04 -82.2,-136.67 -82.2,-134.3 -82.2,-134.3 -82.33,-134.3 -82.46,-134.3 -82.59,-134.3 -82.72,-134.3 -82.85,-134.3 -82.98,-134.3 -83.11,-134.3 -83.24,-134.3 -83.37,-134.3 -83.5,-136.67 -83.5,-139.04 -83.5,-141.41 -83.5,-143.78 -83.5,-146.15 -83.5,-148.52 -83.5,-150.89 -83.5,-153.26 -83.5,-155.63 -83.5,-158 -83.5,-158 -83.37,-158 -83.24,-158 -83.11,-158 -82.98,-158 -82.85,-158 -82.72,-158 -82.59,-158 -82.46,-158 -82.33,-158 -82.2))"] | ["POINT(-146.15 -82.85)"] | false | false |
Siple Shallow Core Density Data
|
0126286 |
2003-05-14 | Lamorey, Gregg W. |
Continuous High Resolution Ice-Core Chemistry using ICP-MS at Siple Dome |
This data set is part of the WAISCORES project, an NSF-funded project to understand the influence of the West Antarctic ice sheet on climate and sea level change. WAISCORES researchers acquired and analyzed ice cores from the Siple Dome, in the Siple Coast region, West Antarctica. Lamorey measured the density of the shallow Siple Dome cores B - I. One-meter sections of the ice core were weighed on a balance beam in the field. The volume was determined by measuring the diameter and length of the core. The data consists of tab-delimited text files of density measurements and a sonic velocity profile, and a .gif format density-versus-depth plot. Data are available via FTP. | ["POINT(-149 -81)"] | ["POINT(-149 -81)"] | false | false |
Ice Velocity Data from Ice Stream C, West Antarctica
|
9318121 9222121 |
2001-12-01 | Anandakrishnan, Sridhar |
Microearthquake Monitoring of Ice Stream C, West Antarctica: A Sensor for Sticky Spots |
Ice velocity data from ice stream C, including the body of the ice stream and its area of onset, are available. The investigator calculated velocities from precise ice displacement measurements made with a geodetic-quality Global Positioning System (GPS). These ice displacement measurements accompanied seismic experiments aimed at understanding controls on the flow of ice streams in west Antarctica. An understanding of ice stream flow is essential to predicting the response of the West Antarctic Ice Sheet to future climate change. Data are available in ASCII format via ftp. | ["POLYGON((-121.644 -82.2764,-121.4814 -82.2764,-121.3188 -82.2764,-121.1562 -82.2764,-120.9936 -82.2764,-120.831 -82.2764,-120.6684 -82.2764,-120.5058 -82.2764,-120.3432 -82.2764,-120.1806 -82.2764,-120.018 -82.2764,-120.018 -82.28496,-120.018 -82.29352,-120.018 -82.30208,-120.018 -82.31064,-120.018 -82.3192,-120.018 -82.32776,-120.018 -82.33632,-120.018 -82.34488,-120.018 -82.35344,-120.018 -82.362,-120.1806 -82.362,-120.3432 -82.362,-120.5058 -82.362,-120.6684 -82.362,-120.831 -82.362,-120.9936 -82.362,-121.1562 -82.362,-121.3188 -82.362,-121.4814 -82.362,-121.644 -82.362,-121.644 -82.35344,-121.644 -82.34488,-121.644 -82.33632,-121.644 -82.32776,-121.644 -82.3192,-121.644 -82.31064,-121.644 -82.30208,-121.644 -82.29352,-121.644 -82.28496,-121.644 -82.2764))", "POLYGON((-152.598 -81.8039,-149.8369 -81.8039,-147.0758 -81.8039,-144.3147 -81.8039,-141.5536 -81.8039,-138.7925 -81.8039,-136.0314 -81.8039,-133.2703 -81.8039,-130.5092 -81.8039,-127.7481 -81.8039,-124.987 -81.8039,-124.987 -81.90464,-124.987 -82.00538,-124.987 -82.10612,-124.987 -82.20686,-124.987 -82.3076,-124.987 -82.40834,-124.987 -82.50908,-124.987 -82.60982,-124.987 -82.71056,-124.987 -82.8113,-127.7481 -82.8113,-130.5092 -82.8113,-133.2703 -82.8113,-136.0314 -82.8113,-138.7925 -82.8113,-141.5536 -82.8113,-144.3147 -82.8113,-147.0758 -82.8113,-149.8369 -82.8113,-152.598 -82.8113,-152.598 -82.71056,-152.598 -82.60982,-152.598 -82.50908,-152.598 -82.40834,-152.598 -82.3076,-152.598 -82.20686,-152.598 -82.10612,-152.598 -82.00538,-152.598 -81.90464,-152.598 -81.8039))"] | ["POINT(-120.831 -82.3192)", "POINT(-138.7925 -82.3076)"] | false | false |