{"dp_type": "Dataset", "free_text": "Glaciation"}
[{"awards": "1903681 Brook, Edward J.", "bounds_geometry": ["POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))"], "date_created": "Wed, 26 Jun 2024 00:00:00 GMT", "description": "This data set is a new N2O isotopic data set including site preference isotopic data derived from ice core samples containing air spanning the deglacial N2O rise (16.5-13.2 ka). The data extend through the Younger Dryas cooling interval, when N2O decreased by about 30 ppb (13.2-11.9 ka). The data set also contains N2O isotope records spanning the Heinrich Stadial 4 / Dansgaard-Oeschger 8 (HS4/DO8) transition (39.8-35.8 ka), an example of cyclical millennial-scale N2O variability characteristic of the last ice age. ", "east": 162.5, "geometry": ["POINT(161.25 -77.75)"], "keywords": "Antarctica; Cryosphere; Ice Core; Nitrous Oxide; Taylor Glacier", "locations": "Taylor Glacier; Antarctica; Taylor Glacier", "north": -77.6, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Menking, Andy; Brook, Edward J.", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -77.9, "title": "Final N2O isotopic data including isotopomer ratios for the last deglaciation and Heinrich Stadia 4/Dansgaard Oeschger Event 8", "uid": "601803", "west": 160.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POINT(-64.207 -64.86)"], "date_created": "Wed, 24 Apr 2024 00:00:00 GMT", "description": "This dataset includes measurements of opal (wt %), total organic carbon (wt %), total nitrogen (wt%), bulk nitrogen isotopic composition (d15Nbulk; \u2030 vs air), and diatom-bound nitrogen isotopic composition (d15Ndb; \u2030 vs air) from 36 samples from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments were deposited during a period of deglaciation about 12.5-12.3 ka.", "east": -64.207, "geometry": ["POINT(-64.207 -64.86)"], "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "locations": "Antarctic Peninsula; Antarctica", "north": -64.86, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.86, "title": "Sediment chemistry of ODP Site 1098", "uid": "601778", "west": -64.207}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POINT(-64 -65)"], "date_created": "Wed, 24 Apr 2024 00:00:00 GMT", "description": "This dataset includes diatom assemblage and surface area data from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments are laminated and were deposited during a period of deglaciation about 12.5-12.3 ka. Quantitative diatom assemblage counts and surface area measurements are reported for 12 samples.", "east": -64.0, "geometry": ["POINT(-64 -65)"], "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Sediment Core Data", "locations": "Antarctic Peninsula; Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "ODP Site 1098 deglacial diatom assemblage", "uid": "601777", "west": -64.0}, {"awards": "1745078 Brook, Edward J.", "bounds_geometry": ["POINT(-112.05 -79.28)"], "date_created": "Thu, 05 Oct 2023 00:00:00 GMT", "description": "This dataset includes measurements of atmospheric methane from samples from the NEEM, GISP2 and WAIS Divide ice cores. All measurements were made at the Oregon State University Ice Core and Quaternary Geochemistry Laboratory (Corvallis, OR) using an established analytical system. 433 samples from the NEEM ice core were measured between 1420 and 1560m depths. A measurement uncertainty ranging from 2.8 to 4.2 ppb, depending on the measurement year, was determined from replicate samples. 340 samples from the GISP2 ice core were measured between 1740 and 2060m depths. A measurement uncertainty ranging from 3.1 to 3.4 ppb, depending on the measurement year, was determined from replicate samples. All GISP2 and NEEM data were corrected for excess methane contamination using the established relationship between excess methane and Ca2+ (Lee et al., 2020). Both corrected and uncorrected data are included in the publication. 340 samples from the GISP2 ice core were measured between 1957 and 3081m depths. A measurement uncertainty ranging from 3.1 to 3.4 ppb, depending on the measurement year, was determined from replicate samples. Depths reflect the mid-points of the depth range of each samples, which is typically ~8cm. All replicate measurements are included in the dataset.\r\n\r\nLee, J. E. et al. Excess methane in Greenland ice cores associated with high dust concentrations. Geochimica et cosmochimica acta 270, 409-430 (2020).", "east": -112.05, "geometry": ["POINT(-112.05 -79.28)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Greenland; Ice Core Records; Methane; West Antarctic Ice Sheet", "locations": "West Antarctic Ice Sheet; Antarctica; Greenland", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Riddell-Young, Benjamin; Martin, Kaden; Rosen, Julia; Lee, James; Edwards, Jon S.; Brook, Edward J.", "project_titles": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores", "projects": [{"proj_uid": "p0010416", "repository": "USAP-DC", "title": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.28, "title": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ", "uid": "601737", "west": -112.05}, {"awards": "1745078 Brook, Edward J.", "bounds_geometry": ["POINT(-112.05 -79.28)"], "date_created": "Mon, 02 Oct 2023 00:00:00 GMT", "description": "This dataset includes estimates of the atmospheric methane relative interpolar difference (rIPD) across the Last Glacial Maximum and Deglaciation. The rIPD was calculated using discrete, high-resolution methane measurements from the WAIS Divide, NEEM and GISP2 ice cores. Two independent IPD records were determined: One using NEEM and WAIS and one using GISP2 and WAIS. The dataset includes rIPD values calculated using both Greenland methane data both corrected and uncorrected for excess methane (Lee et al., 2020). The rIPD was calculated by smoothing each methane record and synchronizing them to the WD2014 gas age scale. 1-sigma rIPD uncertainties are included. This dataset also includes the output of the four-box troposphere model used to interpret the rIPD. For both excess methane-corrected records, the model output and 1-sigma uncertainty is provided for northern extratropical (30N - 90N) and total tropical (30S - 30N) sources in Tg yr-1. For the NEEM-derived rIPD, sections of the rIPD where atmospheric methane changed rapidly were deemed untrustworthy were removed from the dataset.\r\n\r\nLee, J. E. et al. Excess methane in Greenland ice cores associated with high dust concentrations. Geochimica et cosmochimica acta 270, 409-430 (2020).", "east": -112.05, "geometry": ["POINT(-112.05 -79.28)"], "keywords": "Antarctica; Greenland; Methane; Paleoclimate; West Antarctic Ice Sheet", "locations": "Greenland; West Antarctic Ice Sheet; Antarctica", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Riddell-Young, Benjamin; Rosen, Julia; Buizert, Christo; Martin, Kaden; Lee, James; Edwards, Jon S.; M\u00fchl, Michaela; Schmitt, Jochen; Fischer, Hubertus; Blunier, Thomas; Brook, Edward J.", "project_titles": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores", "projects": [{"proj_uid": "p0010416", "repository": "USAP-DC", "title": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.28, "title": "Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation", "uid": "601736", "west": -112.05}, {"awards": "1245659 Petrenko, Vasilii; 1245821 Brook, Edward J.; 1246148 Severinghaus, Jeffrey", "bounds_geometry": ["POLYGON((161 -77.7,161.1 -77.7,161.2 -77.7,161.3 -77.7,161.4 -77.7,161.5 -77.7,161.6 -77.7,161.7 -77.7,161.8 -77.7,161.9 -77.7,162 -77.7,162 -77.71000000000001,162 -77.72,162 -77.73,162 -77.74,162 -77.75,162 -77.76,162 -77.77,162 -77.78,162 -77.78999999999999,162 -77.8,161.9 -77.8,161.8 -77.8,161.7 -77.8,161.6 -77.8,161.5 -77.8,161.4 -77.8,161.3 -77.8,161.2 -77.8,161.1 -77.8,161 -77.8,161 -77.78999999999999,161 -77.78,161 -77.77,161 -77.76,161 -77.75,161 -77.74,161 -77.73,161 -77.72,161 -77.71000000000001,161 -77.7))"], "date_created": "Tue, 23 Aug 2022 00:00:00 GMT", "description": "High-precision carbon isotope data (d13C-CO2) show atmospheric CO2 during Marine Isotope Stage 4 (MIS 4, ~70.5-59 ka) was controlled by a succession of millennial-scale processes. Enriched d13C-CO2 during peak glaciation suggests increased ocean carbon storage. Variations in d13C-CO2 in early MIS4 suggest multiple processes were active during CO2 drawdown, potentially including decreased land carbon and decreased Southern Ocean air-sea gas exchange superposed on increased ocean carbon storage. CO2 remained low during MIS 4 while d13C-CO2 fluctuations suggest changes in Southern Ocean and North Atlantic air-sea gas exchange. A 7 ppm increase in CO2 at the onset of Dansgaard-Oeschger event 19 (72.1 ka) and a 22 ppm increase in CO2 during late MIS 4 (Heinrich Stadial 6, ~63.5-60 ka) involved additions of isotopically light carbon to the atmosphere. The terrestrial biosphere and Southern Ocean air-sea gas exchange are possible sources, with the latter event also involving decreased ocean carbon storage.", "east": 162.0, "geometry": ["POINT(161.5 -77.75)"], "keywords": "Antarctica; Taylor Glacier", "locations": "Taylor Glacier; Antarctica", "north": -77.7, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "persons": "Menking, James; Shackleton, Sarah; Bauska, Thomas; Buffen, Aron; Brook, Edward J.; Barker, Stephen; Severinghaus, Jeffrey P.; Dyonisius, Michael; Petrenko, Vasilii; Menking, Andy", "project_titles": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "projects": [{"proj_uid": "p0000283", "repository": "USAP-DC", "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Taylor Glacier CO2 Isotope Data 74-59 kyr", "uid": "601600", "west": 161.0}, {"awards": "1903681 Brook, Edward J.", "bounds_geometry": ["POLYGON((161.745 -77.745,161.746 -77.745,161.747 -77.745,161.748 -77.745,161.749 -77.745,161.75 -77.745,161.751 -77.745,161.752 -77.745,161.753 -77.745,161.754 -77.745,161.755 -77.745,161.755 -77.74600000000001,161.755 -77.747,161.755 -77.748,161.755 -77.749,161.755 -77.75,161.755 -77.751,161.755 -77.752,161.755 -77.753,161.755 -77.75399999999999,161.755 -77.755,161.754 -77.755,161.753 -77.755,161.752 -77.755,161.751 -77.755,161.75 -77.755,161.749 -77.755,161.748 -77.755,161.747 -77.755,161.746 -77.755,161.745 -77.755,161.745 -77.75399999999999,161.745 -77.753,161.745 -77.752,161.745 -77.751,161.745 -77.75,161.745 -77.749,161.745 -77.748,161.745 -77.747,161.745 -77.74600000000001,161.745 -77.745))"], "date_created": "Tue, 02 Aug 2022 00:00:00 GMT", "description": "Measurements of the isotopic composition of atmospheric nitrous oxide from samples from the Taylor Glacier, Antarctica, spanning the last deglaciation (21-11 ka) and part of the last glacial period (40 to 36 ka). Data set includes the site preference of 15-N in N2O. A manuscript describing these data is currently in preparation. Data are referenced to in house air standards at OSU which are currently being cross calibrated with other laboratories. ", "east": 161.755, "geometry": ["POINT(161.75 -77.75)"], "keywords": "Antarctica; Nitrous Oxide; Taylor Glacier", "locations": "Taylor Glacier; Antarctica", "north": -77.745, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Menking, Andy; Brook, Edward J.", "project_titles": "Deciphering Changes in Atmospheric Nitrous Oxide Concentration During the Last Ice Age Using the Intramolecular Site-Preference of Nitrogen Isotopes", "projects": [{"proj_uid": "p0010465", "repository": "USAP-DC", "title": "Deciphering Changes in Atmospheric Nitrous Oxide Concentration During the Last Ice Age Using the Intramolecular Site-Preference of Nitrogen Isotopes"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.755, "title": "Preliminary nitrous oxide site preference isotopic data for last deglaciation from Taylor Glacier", "uid": "601592", "west": 161.745}, {"awards": "1743643 Passchier, Sandra", "bounds_geometry": ["POINT(-42.933 -61.849)"], "date_created": "Wed, 22 Jun 2022 00:00:00 GMT", "description": "This dataset contains measurements of major and trace elements on 190 samples of Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. The composition of detrital, biogenic and authigenic sediment components was assessed via whole rock geochemistry of sediment samples. Instrument analysis was completed at Montclair State University.", "east": -42.933, "geometry": ["POINT(-42.933 -61.849)"], "keywords": "Antarctica; Glaciation; IODP 650; IODP 696; Paleoceanography; Provenance; Sediment Core Data; Weathering; Weddell Sea", "locations": "Weddell Sea; Antarctica", "north": -61.849, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Hojnacki, Victoria; Li, Xiaona; States, Abbey; Lepp, Allison", "project_titles": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition", "projects": [{"proj_uid": "p0010101", "repository": "USAP-DC", "title": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.849, "title": "Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent", "uid": "601582", "west": -42.933}, {"awards": "1743643 Passchier, Sandra", "bounds_geometry": ["POINT(-42.933 -61.849)"], "date_created": "Tue, 21 Jun 2022 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Diatoms were generally either absent or present in trace amounts in the Eocene-Oligocene interval and were not removed. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive Index of 1.6 (Illite) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": -42.933, "geometry": ["POINT(-42.933 -61.849)"], "keywords": "Antarctica; Glaciation; IODP 696; Marine Geoscience; Marine Sediments; Paleoceanography; Sediment Core Data; Weddell Sea", "locations": "Weddell Sea; Antarctica", "north": -61.849, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Lepp, Allison; Horowitz Castaldo, Josie; Light, Jennifer", "project_titles": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition", "projects": [{"proj_uid": "p0010101", "repository": "USAP-DC", "title": "Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.849, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 696, South Orkney Microcontinent", "uid": "601581", "west": -42.933}, {"awards": "1738942 Wellner, Julia", "bounds_geometry": ["POLYGON((-107.38 -74.64,-107.065 -74.64,-106.75 -74.64,-106.435 -74.64,-106.12 -74.64,-105.805 -74.64,-105.49 -74.64,-105.175 -74.64,-104.86 -74.64,-104.545 -74.64,-104.23 -74.64,-104.23 -74.683,-104.23 -74.726,-104.23 -74.769,-104.23 -74.812,-104.23 -74.855,-104.23 -74.898,-104.23 -74.941,-104.23 -74.984,-104.23 -75.027,-104.23 -75.07,-104.545 -75.07,-104.86 -75.07,-105.175 -75.07,-105.49 -75.07,-105.805 -75.07,-106.12 -75.07,-106.435 -75.07,-106.75 -75.07,-107.065 -75.07,-107.38 -75.07,-107.38 -75.027,-107.38 -74.984,-107.38 -74.941,-107.38 -74.898,-107.38 -74.855,-107.38 -74.812,-107.38 -74.769,-107.38 -74.726,-107.38 -74.683,-107.38 -74.64))"], "date_created": "Thu, 27 Jan 2022 00:00:00 GMT", "description": "This dataset contains measurements from grain-size, x-ray fluorescence (XRF), and physical properties (including magnetic susceptibility, water content, and shear strength) analyses of five sediment cores collected offshore Thwaites Glacier during cruises NBP19-02 (cores KC04, KC08, and KC23) and NBP20-02 (cores KC33 and KC67). We estimate the cores, which are between 213.5 and 297.5 cm in length, reflect deposition during the last ~10 kyr, consistent with published constraints of deglaciation of this region. Data are organized in Microsoft Excel spreadsheets and core locations are provided in a PDF.", "east": -104.23, "geometry": ["POINT(-105.805 -74.855)"], "keywords": "Antarctica; Chemistry:sediment; Chemistry:Sediment; Glaciomarine Sediment; Grain Size; Magnetic Susceptibility; Marine Geoscience; Marine Sediments; NBP1902; NBP2002; Physical Properties; R/v Nathaniel B. Palmer; Sediment Core Data; Thwaites Glacier; Trace Elements; XRF", "locations": "Thwaites Glacier; Antarctica", "north": -74.64, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Lepp, Allison", "project_titles": "NSF-NERC: THwaites Offshore Research (THOR)", "projects": [{"proj_uid": "p0010062", "repository": "USAP-DC", "title": "NSF-NERC: THwaites Offshore Research (THOR)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.07, "title": "Physical and geochemical data from five sediment cores collected offshore Thwaites Glacier", "uid": "601514", "west": -107.38}, {"awards": "1246353 Anderson, John; 1745043 Simkins, Lauren; 1745055 Stearns, Leigh", "bounds_geometry": ["POLYGON((174 -75,174.4 -75,174.8 -75,175.2 -75,175.6 -75,176 -75,176.4 -75,176.8 -75,177.2 -75,177.6 -75,178 -75,178 -75.2,178 -75.4,178 -75.6,178 -75.8,178 -76,178 -76.2,178 -76.4,178 -76.6,178 -76.8,178 -77,177.6 -77,177.2 -77,176.8 -77,176.4 -77,176 -77,175.6 -77,175.2 -77,174.8 -77,174.4 -77,174 -77,174 -76.8,174 -76.6,174 -76.4,174 -76.2,174 -76,174 -75.8,174 -75.6,174 -75.4,174 -75.2,174 -75))"], "date_created": "Mon, 04 Oct 2021 00:00:00 GMT", "description": "Bathymetry from multibeam echo sounding data in Pennell Trough, Ross Sea, Antarctica 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 a 1\u00b0\u00d71\u00b0 beam width, swath angular coverage set to 62\u00b0\u00d762\u00b0, and 30-60% overlap between survey lines. All raw, ping-edited geophysical data collected on NBP15-02 can be accessed using the Marine Geoscience Data System (Cruise DOI: 10.7284/901477). The bathymetry dataset here is gridded at 20-m resolution with a water depth-dependent vertical resolution on the order of decimeters. Two shapefiles are provided for ice-marginal landforms and meltwater landforms observable in the bathymetry data. The purpose of collecting the bathymetry data on cruise NBP15-02 was to better understand the glacial history of the Ross Sea, and the dataset, inclusive of bathymetry data and shapefiles of glacial landforms, from Pennell Trough are used to understand impacts on subglacial channel morphology and organization during the deglaciation of the region following the Last Glacial Maximum. The published dataset was used and analyzed in the article \"Topographic controls on channelized meltwater in the subglacial environment\" by Simkins, L.M., Greenwood, S.L., Munevar Garcia, S., Eareckson, E.A., Anderson, J.B., and Prothro, L.O, which was published in Geophysical Research Letters in 2021 (DOI: 10.1029/2021GL094678).", "east": 178.0, "geometry": ["POINT(176 -76)"], "keywords": "Antarctica; Bathymetry; Elevation; Geomorphology; Glacial History; Glaciers/ice Sheet; Glaciers/Ice Sheet; Marine Geoscience; NBP1502; Pennell Trough; Ross Sea; R/v Nathaniel B. Palmer", "locations": "Ross Sea; Pennell Trough; Antarctica", "north": -75.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Greenwood, Sarah; Munevar Garcia, Santiago; Eareckson, Elizabeth; Anderson, John; Prothro, Lindsay; Simkins, Lauren", "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": "p0010269", "repository": "USAP-DC", "title": "Collaborative Research: Topographic controls on Antarctic Ice Sheet grounding line retreat - integrating models and observations"}, {"proj_uid": "p0000395", "repository": "USAP-DC", "title": "Evidence for Paleo Ice Stream Collapse in the Western Ross Sea since the Last Glacial Maximum."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.0, "title": "Pennell Trough, Ross Sea bathymetry and glacial landforms", "uid": "601474", "west": 174.0}, {"awards": "1245283 Passchier, Sandra", "bounds_geometry": ["POINT(75.4045 -67.549667)"], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 742 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 75.4045, "geometry": ["POINT(75.4045 -67.549667)"], "keywords": "Antarctica; Eocene; Marine Geoscience; ODP742; Oligocene; Particle Size; Prydz Bay; Sediment Core Data", "locations": "Prydz Bay; Antarctica", "north": -67.549667, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Ciarletta, Daniel", "project_titles": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin", "projects": [{"proj_uid": "p0000309", "repository": "USAP-DC", "title": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.549667, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 742, Prydz Bay", "uid": "601454", "west": 75.4045}, {"awards": "1245283 Passchier, Sandra", "bounds_geometry": ["POINT(74.787 -67.696167)"], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene sediment from Ocean Drilling Program Site 1166 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 74.787, "geometry": ["POINT(74.787 -67.696167)"], "keywords": "Antarctica; Eocene; Marine Geoscience; ODP1166; Particle Size; Prydz Bay; Sediment Core Data", "locations": "Prydz Bay; Antarctica", "north": -67.696167, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Ciarletta, Daniel", "project_titles": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin", "projects": [{"proj_uid": "p0000309", "repository": "USAP-DC", "title": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.696167, "title": "Particle-size distributions of Eocene sediment from ODP Site 1166, Prydz Bay", "uid": "601455", "west": 74.787}, {"awards": "1245283 Passchier, Sandra", "bounds_geometry": ["POINT(75.081833 -67.276167)"], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 739 in Prydz Bay. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles.", "east": 75.081833, "geometry": ["POINT(75.081833 -67.276167)"], "keywords": "Antarctica; Eocene; Marine Geoscience; ODP739; Oligocene; Particle Size; Prydz Bay; Sediment Core Data", "locations": "Prydz Bay; Antarctica", "north": -67.276167, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Passchier, Sandra; Ciarletta, Daniel", "project_titles": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin", "projects": [{"proj_uid": "p0000309", "repository": "USAP-DC", "title": "The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.276167, "title": "Particle-size distributions of Eocene-Oligocene sediment from ODP Site 739, Prydz Bay", "uid": "601453", "west": 75.081833}, {"awards": "1543229 Severinghaus, Jeffrey; 1543267 Brook, Edward J.", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 22 Oct 2020 00:00:00 GMT", "description": "Stable isotope ratios of atmospheric krypton, argon, nitrogen and oxygen were measured in late-Holocene ice core samples from nine sites in Antarctica and Greenland, for the purpose of calibrating the Kr-86 excess proxy as defined in Buizert and Severinghaus (2016).", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Bruce Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Greenland Ice Cap; Ice Core; Ice Core Chemistry; Ice Core Records; James Ross Island; Krypton; Law Dome; Low Dome Ice Core; Roosevelt Island; Siple Dome; Siple Dome Ice Core; South Pole; SPICEcore; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; South Pole; Siple Dome; Law Dome; Roosevelt Island; Greenland Ice Cap; James Ross Island; Bruce Plateau; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Buizert, Christo; Shackleton, Sarah; Severinghaus, Jeffrey P.; Brook, Edward J.; Baggenstos, Daniel; Bereiter, Bernhard; Etheridge, David; Bertler, Nancy; Pyne, Rebecca L.; Mulvaney, Robert; Mosley-Thompson, Ellen", "project_titles": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation", "projects": [{"proj_uid": "p0010037", "repository": "USAP-DC", "title": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core; SPICEcore; Siple Dome Ice Core", "south": -90.0, "title": "Multi-site ice core Krypton stable isotope ratios", "uid": "601394", "west": -180.0}, {"awards": "0944021 Brook, Edward J.", "bounds_geometry": ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"], "date_created": "Mon, 13 Jul 2020 00:00:00 GMT", "description": "Data archived here were used to create the Roosevelt Island Ice Core gas age and ice age time scales. Data include methane concentrations, nitrogen and oxygen isotope ratios of N2 and O2, total air content and the D/H ratio of the ice. Derived products included here include ice age and gas age time scales. ", "east": -161.0, "geometry": ["POINT(-162 -79.25)"], "keywords": "Antarctica; CO2; Ice Core; Roosevelt Island", "locations": "Roosevelt Island; Roosevelt Island; Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Brook, Edward J.; Lee, James", "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": -79.5, "title": "Roosevelt Island Ice Core Time Scale and Associated Data", "uid": "601359", "west": -163.0}, {"awards": "1245659 Petrenko, Vasilii", "bounds_geometry": ["POINT(161.71353 -77.75855)"], "date_created": "Fri, 28 Feb 2020 00:00:00 GMT", "description": "This data set contains measurements of 14CH4 and 14CO in ice cores from Taylor Glacier, Antarctica. This includes measurements in ice from the last deglaciation (18 - 8 kyr), for the purposes of paleoatmospheric 14CH4 reconstruction. The data set also includes measurements in older ice (50 - 70 kyr) from a deep ice core, made for the purposes of studying in situ cosmogenic 14C production in ice. All data are in excel format.", "east": 161.71353, "geometry": ["POINT(161.71353 -77.75855)"], "keywords": "Antarctica; Carbon-14; Cosmogenic; Ice Core; Methane", "locations": "Antarctica", "north": -77.75855, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Petrenko, Vasilii; Dyonisius, Michael", "project_titles": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "projects": [{"proj_uid": "p0000283", "repository": "USAP-DC", "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.75855, "title": "Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation and Deep Core Results", "uid": "601260", "west": 161.71353}, {"awards": "1443346 Stone, John", "bounds_geometry": ["POLYGON((-174 -84.5,-172.4 -84.5,-170.8 -84.5,-169.2 -84.5,-167.6 -84.5,-166 -84.5,-164.4 -84.5,-162.8 -84.5,-161.2 -84.5,-159.6 -84.5,-158 -84.5,-158 -84.63,-158 -84.76,-158 -84.89,-158 -85.02,-158 -85.15,-158 -85.28,-158 -85.41,-158 -85.54,-158 -85.67,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.67,-174 -85.54,-174 -85.41,-174 -85.28,-174 -85.15,-174 -85.02,-174 -84.89,-174 -84.76,-174 -84.63,-174 -84.5))"], "date_created": "Thu, 21 Nov 2019 00:00:00 GMT", "description": "This data set contains measurements of cosmic-ray-produced Be-10 in quartz from glacial erratics and bedrock at sites along and adjacent to Liv Glacier and Amundsen Glacier in the southern Transantarctic Mountains. Samples were collected during the 2016-17 and 2017-18 field seasons working from remote camps along the coast. Locations were determined by hand-held GPS. Elevations are based on barometric altimetry corrected for daily drift and referenced to precise (geodetic) GPS benchmarks established over a range of altitudes at each site. Horizon geometry and the resulting topographic shielding of the cosmic ray flux was determined from vertically-oriented full-sky (fisheye) photographs at each sample location. Samples were processed at the University of Washington Cosmogenic Nuclide Laboratory using established procedures for mineral separation, dissolution, beryllium extraction and purification, described at http://depts.washington.edu/cosmolab/chem.shtml. Beryllium isotope ratios were measured at the Lawrence Livermore Center for Accelerator Mass Spectrometry (LLNL-CAMS) relative to the KNSTD-Be-01-5-4 standard, assuming a standard Be-10/Be-9 ratio of 2.851E-12 (07KNSTD normalization). Data are reported as input for the online CRONUS cosmogenic nuclide calculator (V3, current at the time of submission in November 2019). Exposure ages can be obtained by entering the data into the CRONUS calculator, at: http://hess.ess.washington.edu/math/v3/v3_age_in.html .\r\nData for each sample consists of two lines of input parameters, as follows:\t\t\t\t\t\t\t\t\t\r\n{Sample_name, Latitude (DD), Longitude (DD), Altitude (m asl), Scaling_function, Thickness (cm), Density (g/cm^3), Horizon_correction, Erosion_rate (cm/yr), Year_sampled}\r\n{Sample_name, Nuclide (in this case Be-10), Target_mineral (quartz), Be-10_concentration (atom/g), Error_Be-10_concentration (atom/g), Normalization}\r\nFurther information about the V3 input format is given at:\r\nhttp://hess.ess.washington.edu/math/docs/v3/v3_input_explained.html", "east": -158.0, "geometry": ["POINT(-166 -85.15)"], "keywords": "Antarctica; Be-10; Beryllium-10; Cosmogenic; Cosmogenic Dating; Cosmogenic Radionuclides; Deglaciation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Liv Glacier; Rocks; Ross Ice Sheet; Surface Exposure Dates; Transantarctic Mountains", "locations": "Transantarctic Mountains; Liv Glacier; Ross Ice Sheet; Antarctica", "north": -84.5, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Stone, John", "project_titles": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment", "projects": [{"proj_uid": "p0010053", "repository": "USAP-DC", "title": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.8, "title": "Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast", "uid": "601226", "west": -174.0}, {"awards": "1443248 Hall, Brenda", "bounds_geometry": ["POLYGON((-170 -84,-168 -84,-166 -84,-164 -84,-162 -84,-160 -84,-158 -84,-156 -84,-154 -84,-152 -84,-150 -84,-150 -84.16,-150 -84.32,-150 -84.48,-150 -84.64,-150 -84.8,-150 -84.96,-150 -85.12,-150 -85.28,-150 -85.44,-150 -85.6,-152 -85.6,-154 -85.6,-156 -85.6,-158 -85.6,-160 -85.6,-162 -85.6,-164 -85.6,-166 -85.6,-168 -85.6,-170 -85.6,-170 -85.44,-170 -85.28,-170 -85.12,-170 -84.96,-170 -84.8,-170 -84.64,-170 -84.48,-170 -84.32,-170 -84.16,-170 -84))"], "date_created": "Thu, 05 Sep 2019 00:00:00 GMT", "description": "", "east": -150.0, "geometry": ["POINT(-160 -84.8)"], "keywords": "Antarctica; Carbon; Glaciology; Holocene; Radiocarbon; Ross Embayment; Ross Sea; Transantarctic Mountains", "locations": "Ross Embayment; Ross Sea; Transantarctic Mountains; Antarctica", "north": -84.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hall, Brenda", "project_titles": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment", "projects": [{"proj_uid": "p0010053", "repository": "USAP-DC", "title": "Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.6, "title": "Liv and Amundsen Glacier Radiocarbon Data", "uid": "601208", "west": -170.0}, {"awards": "1543229 Severinghaus, Jeffrey", "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, 02 Aug 2019 00:00:00 GMT", "description": "This data comprises a survey of Recent ice from multiple sites in Antarctica using shallow ice cores to examine noble gas values in ice that nominally has the same Mean Ocean Temperature as today. The goal is to elucidate fractionation that occurs in the firn before air is trapped in bubbles in the ice, by making the assumption that the atmosphere noble gas content has not changed since this air was trappped. The ages of the air samples are typically early Industrial Revolution or late Holocene.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Krypton; Noble Gas; Xenon", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Severinghaus, Jeffrey P.; Shackleton, Sarah", "project_titles": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation", "projects": [{"proj_uid": "p0010037", "repository": "USAP-DC", "title": "Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last\r\ndeglaciation"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Noble Gas Data from recent ice in Antarctica for 86Kr problem", "uid": "601195", "west": -180.0}, {"awards": "0943466 Hawley, Robert", "bounds_geometry": ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"], "date_created": "Tue, 13 Feb 2018 00:00:00 GMT", "description": "A Borehole Optical Televiewer (OPTV) uses a conical mirror and scanning electronics to record a continuous 360-degree image of the borehole wall. An inclinometer and magnetometer allow the image to be \u0027unwrapped\u0027 and resented as a rectangular image, which shows the visible features of the wall oriented to magnetic north. This dataset includes both the raw bitmap (bmp) image data from the televiewer, as well as proprietary WellCad format (wcl) files. The WellCad format files contain the inclinometry, orientation, and temperature data in addition to the imagery data. Wellcad files can be viewed with a free wellcad file reader available from https://www.alt.lu/downloads.htm. This dataset includes OPTV logs from each of two seasons, November 2013 and 2014. The logs are of the 760 m deep hole drilled by the RICE project, a NZ-USA partnership.", "east": -161.0, "geometry": ["POINT(-162 -79.25)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Roosevelt Island; Snow/ice; Snow/Ice", "locations": "Roosevelt Island; Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "persons": "Hawley, Robert L.; Clemens-Sewall, David", "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": -79.5, "title": "Roosevelt Island Borehole Optical Televiewer logs", "uid": "601086", "west": -163.0}, {"awards": "0943466 Hawley, Robert", "bounds_geometry": ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"], "date_created": "Tue, 13 Feb 2018 00:00:00 GMT", "description": "These data are firn temperatures, measured by a meteorological station placed at Roosevelt Island. Thermistors were placed at multiple depths through the upper 20 meters of firn and measured through the course of roughly one year.", "east": -161.0, "geometry": ["POINT(-162 -79.25)"], "keywords": "Antarctica; Borehole; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Records; Ice Fabric; Optical Images; Roosevelt Island; Snow/ice; Snow/Ice; Temperature", "locations": "Roosevelt Island; Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "persons": "Hawley, Robert L.; Clemens-Sewall, David; Giese, Alexandra", "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": -79.5, "title": "Roosevelt Island Borehole Firn temperatures", "uid": "601085", "west": -163.0}, {"awards": "1245899 Kowalewski, Douglas", "bounds_geometry": ["POLYGON((160 -70,168 -70,176 -70,184 -70,192 -70,200 -70,208 -70,216 -70,224 -70,232 -70,240 -70,240 -71.5,240 -73,240 -74.5,240 -76,240 -77.5,240 -79,240 -80.5,240 -82,240 -83.5,240 -85,232 -85,224 -85,216 -85,208 -85,200 -85,192 -85,184 -85,176 -85,168 -85,160 -85,160 -83.5,160 -82,160 -80.5,160 -79,160 -77.5,160 -76,160 -74.5,160 -73,160 -71.5,160 -70))"], "date_created": "Tue, 16 Jan 2018 00:00:00 GMT", "description": "Data here is output from regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession during the Plio-Pleistocene.", "east": 240.0, "geometry": ["POINT(-160 -77.5)"], "keywords": "Antarctica; Climate Model; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model; McMurdo; Paleoclimate; Ross Sea", "locations": "McMurdo; Ross Sea; Antarctica", "north": -70.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Kowalewski, Douglas", "project_titles": "Collaborative Research: West Antarctic Ice Sheet stability, Alpine Glaciation, and Climate Variability: a Terrestrial Perspective from Cosmogenic-nuclide Dating in McMurdo Sound", "projects": [{"proj_uid": "p0000391", "repository": "USAP-DC", "title": "Collaborative Research: West Antarctic Ice Sheet stability, Alpine Glaciation, and Climate Variability: a Terrestrial Perspective from Cosmogenic-nuclide Dating in McMurdo Sound"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.0, "title": "Region Climate Model Output Plio-Pleistocene", "uid": "601080", "west": 160.0}, {"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; Ross Sea; Antarctica", "north": -79.15, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology", "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": "1246170 Hall, Brenda", "bounds_geometry": ["POLYGON((155.4 -79.8,155.54 -79.8,155.68 -79.8,155.82 -79.8,155.96 -79.8,156.1 -79.8,156.24 -79.8,156.38 -79.8,156.52 -79.8,156.66 -79.8,156.8 -79.8,156.8 -79.82,156.8 -79.84,156.8 -79.86,156.8 -79.88,156.8 -79.9,156.8 -79.92,156.8 -79.94,156.8 -79.96,156.8 -79.98,156.8 -80,156.66 -80,156.52 -80,156.38 -80,156.24 -80,156.1 -80,155.96 -80,155.82 -80,155.68 -80,155.54 -80,155.4 -80,155.4 -79.98,155.4 -79.96,155.4 -79.94,155.4 -79.92,155.4 -79.9,155.4 -79.88,155.4 -79.86,155.4 -79.84,155.4 -79.82,155.4 -79.8))"], "date_created": "Mon, 23 Oct 2017 00:00:00 GMT", "description": "Hatherton Glacier Radiocarbon Data", "east": 156.8, "geometry": ["POINT(156.1 -79.9)"], "keywords": "Antarctica; Geochronology; Hatherton Glacier; Radiocarbon; Sample/collection Description; Sample/Collection Description; Transantarctic Mountains", "locations": "Hatherton Glacier; Transantarctic Mountains; Antarctica", "north": -79.8, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Hall, Brenda", "project_titles": "Collaborative Research: Assessing the Antarctic Contribution to Sea-level Changes during the Last Deglaciation: Constraints from Darwin Glacier", "projects": [{"proj_uid": "p0000304", "repository": "USAP-DC", "title": "Collaborative Research: Assessing the Antarctic Contribution to Sea-level Changes during the Last Deglaciation: Constraints from Darwin Glacier"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Hatherton Glacier Radiocarbon Data", "uid": "601063", "west": 155.4}, {"awards": "1142002 Kaplan, Michael", "bounds_geometry": ["POLYGON((-58 -63.7,-57.95 -63.7,-57.9 -63.7,-57.85 -63.7,-57.8 -63.7,-57.75 -63.7,-57.7 -63.7,-57.65 -63.7,-57.6 -63.7,-57.55 -63.7,-57.5 -63.7,-57.5 -63.73,-57.5 -63.76,-57.5 -63.79,-57.5 -63.82,-57.5 -63.85,-57.5 -63.88,-57.5 -63.91,-57.5 -63.94,-57.5 -63.97,-57.5 -64,-57.55 -64,-57.6 -64,-57.65 -64,-57.7 -64,-57.75 -64,-57.8 -64,-57.85 -64,-57.9 -64,-57.95 -64,-58 -64,-58 -63.97,-58 -63.94,-58 -63.91,-58 -63.88,-58 -63.85,-58 -63.82,-58 -63.79,-58 -63.76,-58 -63.73,-58 -63.7))"], "date_created": "Sat, 16 Sep 2017 00:00:00 GMT", "description": "These are data sets obtained with the supported award. The ages concern the histories of glaciers, ice sheets, and general cryospheric and climatic activities of the northern Antarctic Peninsula and surrounding area.They cover periods from prior to the last global glacial maximum (stage 3 and older?) as well as since deglaciation.", "east": -57.5, "geometry": ["POINT(-57.75 -63.85)"], "keywords": "Antarctica; Antarctic Peninsula; Glaciers/ice Sheet; Glaciers/Ice Sheet; GPS; James Ross Island; Sample/collection Description; Sample/Collection Description; Solid Earth", "locations": "Antarctic Peninsula; James Ross Island; Antarctica", "north": -63.7, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Kaplan, Michael", "project_titles": "Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula", "projects": [{"proj_uid": "p0000337", "repository": "USAP-DC", "title": "Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "10Be and 14C data from northern Antarctic Peninsula", "uid": "601051", "west": -58.0}, {"awards": "0839075 Priscu, John", "bounds_geometry": ["POINT(-112.08648 -79.46763)"], "date_created": "Mon, 06 Mar 2017 00:00:00 GMT", "description": "This data set include depth (WDC06A-7 dating) and fluorescence intensity measurements for five fluorophore regions (A, C, M, B, and T) commonly found in natural organic matter. Data from 1300-1700m, 1700-2100m, and 2100-2700m correspond to the early Holocene, deglaciation period, and the Last Glacial Maximum.", "east": -112.08648, "geometry": ["POINT(-112.08648 -79.46763)"], "keywords": "Antarctica; Fluorescence Spectroscopy; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.46763, "nsf_funding_programs": null, "persons": "Priscu, John; D\u0027Andrilli, Juliana", "project_titles": "Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core", "projects": [{"proj_uid": "p0000273", "repository": "USAP-DC", "title": "Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.46763, "title": "Fluorescence spectroscopy data from the West Antarctic Ice Sheet (WAIS) Divide ice core, WDC06A", "uid": "601006", "west": -112.08648}, {"awards": "0839031 Severinghaus, Jeffrey", "bounds_geometry": ["POINT(161.71965 -77.76165)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the \u0027clathrate hypothesis\u0027 that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (\u003e1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a \u0027horizontal ice core\u0027 would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.", "east": 161.71965, "geometry": ["POINT(161.71965 -77.76165)"], "keywords": "Antarctica; Cosmogenic; Geochemistry; Ice Core Records; Paleoclimate; Radiocarbon; Taylor Glacier; Transantarctic Mountains", "locations": "Taylor Glacier; Transantarctic Mountains; Antarctica", "north": -77.76165, "nsf_funding_programs": null, "persons": "Severinghaus, Jeffrey P.", "project_titles": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica", "projects": [{"proj_uid": "p0000099", "repository": "USAP-DC", "title": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.76165, "title": "Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica", "uid": "600165", "west": 161.71965}, {"awards": "1245821 Brook, Edward J.", "bounds_geometry": ["POINT(162.167 -77.733)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, and delta 18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, delta 13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of delta 13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.", "east": 162.167, "geometry": ["POINT(162.167 -77.733)"], "keywords": "Antarctica; Atmosphere; Geochemistry; Ice Core Records; Isotope; Paleoclimate; Taylor Glacier; Transantarctic Mountains", "locations": "Taylor Glacier; Transantarctic Mountains; Antarctica", "north": -77.733, "nsf_funding_programs": null, "persons": "Brook, Edward J.", "project_titles": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "projects": [{"proj_uid": "p0000283", "repository": "USAP-DC", "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.733, "title": "The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "uid": "600163", "west": 162.167}, {"awards": "1142162 Stone, John", "bounds_geometry": ["POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a reconnaissance geological and radar-sounding study of promising sites in West Antarctica for a future project to measure cosmogenic nuclides in subglacial bedrock. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain the highest possible surface detail. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public.", "east": -85.14, "geometry": ["POINT(-94.64 -81.755)"], "keywords": "Antarctica; Be-10; Chemistry:rock; Chemistry:Rock; Cosmogenic Dating; Glaciology; Nunataks; Sample/collection Description; Sample/Collection Description; Solid Earth; Whitmore Mountains", "locations": "Whitmore Mountains; Antarctica", "north": -81.07, "nsf_funding_programs": null, "persons": "Stone, John", "project_titles": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "projects": [{"proj_uid": "p0000335", "repository": "USAP-DC", "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.44, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "uid": "600162", "west": -104.14}, {"awards": "1043018 Pollard, David", "bounds_geometry": ["POINT(-85 -82)"], "date_created": "Thu, 03 Dec 2015 00:00:00 GMT", "description": "Ice-sheet model output of Antarctic Ice Sheet simulations spanning 30,000 years BP to 5000+ years in the future.", "east": -85.0, "geometry": ["POINT(-85 -82)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model", "locations": "Antarctica", "north": -82.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Pollard, David", "project_titles": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "projects": [{"proj_uid": "p0000194", "repository": "USAP-DC", "title": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.0, "title": "Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "uid": "609639", "west": -85.0}, {"awards": "1043485 Curtice, Josh", "bounds_geometry": ["POLYGON((163.4 -77.47989,163.9848 -77.47989,164.5696 -77.47989,165.1544 -77.47989,165.7392 -77.47989,166.324 -77.47989,166.9088 -77.47989,167.4936 -77.47989,168.0784 -77.47989,168.6632 -77.47989,169.248 -77.47989,169.248 -77.565701,169.248 -77.651512,169.248 -77.737323,169.248 -77.823134,169.248 -77.908945,169.248 -77.994756,169.248 -78.080567,169.248 -78.166378,169.248 -78.252189,169.248 -78.338,168.6632 -78.338,168.0784 -78.338,167.4936 -78.338,166.9088 -78.338,166.324 -78.338,165.7392 -78.338,165.1544 -78.338,164.5696 -78.338,163.9848 -78.338,163.4 -78.338,163.4 -78.252189,163.4 -78.166378,163.4 -78.080567,163.4 -77.994756,163.4 -77.908945,163.4 -77.823134,163.4 -77.737323,163.4 -77.651512,163.4 -77.565701,163.4 -77.47989))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "This award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.\n", "east": 169.248, "geometry": ["POINT(166.324 -77.908945)"], "keywords": "Antarctica; Cosmogenic Dating; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean; WAIS", "locations": "WAIS; Ross Sea; Antarctica; Southern Ocean", "north": -77.47989, "nsf_funding_programs": null, "persons": "Kurz, Mark D.; Curtice, Josh", "project_titles": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "projects": [{"proj_uid": "p0000194", "repository": "USAP-DC", "title": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.338, "title": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "uid": "600123", "west": 163.4}, {"awards": "0902957 Robinson, Laura", "bounds_geometry": ["POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))"], "date_created": "Sat, 01 Jan 2011 00:00:00 GMT", "description": "The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project\u0027s goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth\u0027s system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column.", "east": -35.0, "geometry": ["POINT(-52.75 -58)"], "keywords": "Biota; Corals; Drake Passage; Geochronology; NBP0805; Oceans; Paleoclimate; Radiocarbon; Southern Ocean", "locations": "Drake Passage; Southern Ocean", "north": -54.5, "nsf_funding_programs": null, "persons": "Robinson, Laura", "project_titles": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "projects": [{"proj_uid": "p0000519", "repository": "USAP-DC", "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -61.5, "title": "LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals", "uid": "600111", "west": -70.5}, {"awards": "0440954 Miller, Molly", "bounds_geometry": ["POLYGON((159 -76.61667,159.05 -76.61667,159.1 -76.61667,159.15 -76.61667,159.2 -76.61667,159.25 -76.61667,159.3 -76.61667,159.35 -76.61667,159.4 -76.61667,159.45 -76.61667,159.5 -76.61667,159.5 -76.630003,159.5 -76.643336,159.5 -76.656669,159.5 -76.670002,159.5 -76.683335,159.5 -76.696668,159.5 -76.710001,159.5 -76.723334,159.5 -76.736667,159.5 -76.75,159.45 -76.75,159.4 -76.75,159.35 -76.75,159.3 -76.75,159.25 -76.75,159.2 -76.75,159.15 -76.75,159.1 -76.75,159.05 -76.75,159 -76.75,159 -76.736667,159 -76.723334,159 -76.710001,159 -76.696668,159 -76.683335,159 -76.670002,159 -76.656669,159 -76.643336,159 -76.630003,159 -76.61667))"], "date_created": "Thu, 01 Jan 2009 00:00:00 GMT", "description": "This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate. In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.", "east": 159.5, "geometry": ["POINT(159.25 -76.683335)"], "keywords": "Allan Hills; Antarctica; Paleontology; Sample/collection Description; Sample/Collection Description; Solid Earth", "locations": "Allan Hills; Antarctica", "north": -76.61667, "nsf_funding_programs": null, "persons": "Miller, Molly", "project_titles": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "projects": [{"proj_uid": "p0000207", "repository": "USAP-DC", "title": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": -76.75, "title": "Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "uid": "600045", "west": 159.0}, {"awards": "0230197 Holt, John", "bounds_geometry": ["POLYGON((-134.9 -71.7,-129.86 -71.7,-124.82 -71.7,-119.78 -71.7,-114.74 -71.7,-109.7 -71.7,-104.66 -71.7,-99.62 -71.7,-94.58 -71.7,-89.54 -71.7,-84.5 -71.7,-84.5 -72.7,-84.5 -73.7,-84.5 -74.7,-84.5 -75.7,-84.5 -76.7,-84.5 -77.7,-84.5 -78.7,-84.5 -79.7,-84.5 -80.7,-84.5 -81.7,-89.54 -81.7,-94.58 -81.7,-99.62 -81.7,-104.66 -81.7,-109.7 -81.7,-114.74 -81.7,-119.78 -81.7,-124.82 -81.7,-129.86 -81.7,-134.9 -81.7,-134.9 -80.7,-134.9 -79.7,-134.9 -78.7,-134.9 -77.7,-134.9 -76.7,-134.9 -75.7,-134.9 -74.7,-134.9 -73.7,-134.9 -72.7,-134.9 -71.7))"], "date_created": "Wed, 25 Oct 2006 00:00:00 GMT", "description": "This data set includes 5 km gridded data from the Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) conducted during the 2004-2005 austral summer. Investigators derived maps of the ice sheet surface and subglacial topography, which covers the entire catchments of both the Thwaites Glacier and the Pine Islands Glacier, from airborne survey systems mounted on a Twin Otter aircraft. The surveys had sufficient density to identify critical ice dynamic transitions within the Amundsen Sea Embayment (ASE). \n\nThe ASE is the only major drainage to exhibit significant elevation change over the period of available satellite observations. Modeling of the Western Antarctic Ice Sheet (WAIS) deglaciation pinpointed the Pine Island Glacier and the Thwaites Glacier, which comprise a major portion of the ASE, as the most vulnerable features of the WAIS. Present knowledge of the ice thickness and subglacial boundary conditions in the ASE are insufficient to understand its evolution or its sensitivity to climatic change, and it is not yet determined whether these changes are evidence of ongoing deglaciation or simply a fluctuation that does not threaten the equilibrium of the ice sheet. This research will support the efforts of a community of United States and international researchers to assess the present and predict the future behavior of the ice sheet in the ASE. \n\nThese data are available via FTP.", "east": -84.5, "geometry": ["POINT(-109.7 -76.7)"], "keywords": "AGASEA; Airborne Radar; Amundsen Sea; Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Solid Earth", "locations": "Amundsen Sea; Antarctica", "north": -71.7, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Holt, John W.; Blankenship, Donald D.; Morse, David L.; Vaughan, David G.; Corr, Hugh F. J.; Young, Duncan A.", "project_titles": "Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA)", "projects": [{"proj_uid": "p0000243", "repository": "USAP-DC", "title": "Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -81.7, "title": "Subglacial Topography: Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica", "uid": "609292", "west": -134.9}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Final N2O isotopic data including isotopomer ratios for the last deglaciation and Heinrich Stadia 4/Dansgaard Oeschger Event 8
|
1903681 |
2024-06-26 | Menking, Andy; Brook, Edward J. | No project link provided | This data set is a new N2O isotopic data set including site preference isotopic data derived from ice core samples containing air spanning the deglacial N2O rise (16.5-13.2 ka). The data extend through the Younger Dryas cooling interval, when N2O decreased by about 30 ppb (13.2-11.9 ka). The data set also contains N2O isotope records spanning the Heinrich Stadial 4 / Dansgaard-Oeschger 8 (HS4/DO8) transition (39.8-35.8 ka), an example of cyclical millennial-scale N2O variability characteristic of the last ice age. | ["POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))"] | ["POINT(161.25 -77.75)"] | false | false |
Sediment chemistry of ODP Site 1098
|
1744871 |
2024-04-24 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes measurements of opal (wt %), total organic carbon (wt %), total nitrogen (wt%), bulk nitrogen isotopic composition (d15Nbulk; ‰ vs air), and diatom-bound nitrogen isotopic composition (d15Ndb; ‰ vs air) from 36 samples from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments were deposited during a period of deglaciation about 12.5-12.3 ka. | ["POINT(-64.207 -64.86)"] | ["POINT(-64.207 -64.86)"] | false | false |
ODP Site 1098 deglacial diatom assemblage
|
1744871 |
2024-04-24 | Dove, Isabel |
The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information? |
This dataset includes diatom assemblage and surface area data from ODP sediment core 1098B-5H-7 on the western Antarctic Peninsula. The sediments are laminated and were deposited during a period of deglaciation about 12.5-12.3 ka. Quantitative diatom assemblage counts and surface area measurements are reported for 12 samples. | ["POINT(-64 -65)"] | ["POINT(-64 -65)"] | false | false |
Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores
|
1745078 |
2023-10-05 | Riddell-Young, Benjamin; Martin, Kaden; Rosen, Julia; Lee, James; Edwards, Jon S.; Brook, Edward J. |
Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores |
This dataset includes measurements of atmospheric methane from samples from the NEEM, GISP2 and WAIS Divide ice cores. All measurements were made at the Oregon State University Ice Core and Quaternary Geochemistry Laboratory (Corvallis, OR) using an established analytical system. 433 samples from the NEEM ice core were measured between 1420 and 1560m depths. A measurement uncertainty ranging from 2.8 to 4.2 ppb, depending on the measurement year, was determined from replicate samples. 340 samples from the GISP2 ice core were measured between 1740 and 2060m depths. A measurement uncertainty ranging from 3.1 to 3.4 ppb, depending on the measurement year, was determined from replicate samples. All GISP2 and NEEM data were corrected for excess methane contamination using the established relationship between excess methane and Ca2+ (Lee et al., 2020). Both corrected and uncorrected data are included in the publication. 340 samples from the GISP2 ice core were measured between 1957 and 3081m depths. A measurement uncertainty ranging from 3.1 to 3.4 ppb, depending on the measurement year, was determined from replicate samples. Depths reflect the mid-points of the depth range of each samples, which is typically ~8cm. All replicate measurements are included in the dataset. Lee, J. E. et al. Excess methane in Greenland ice cores associated with high dust concentrations. Geochimica et cosmochimica acta 270, 409-430 (2020). | ["POINT(-112.05 -79.28)"] | ["POINT(-112.05 -79.28)"] | false | false |
Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation
|
1745078 |
2023-10-02 | Riddell-Young, Benjamin; Rosen, Julia; Buizert, Christo; Martin, Kaden; Lee, James; Edwards, Jon S.; Mühl, Michaela; Schmitt, Jochen; Fischer, Hubertus; Blunier, Thomas; Brook, Edward J. |
Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores |
This dataset includes estimates of the atmospheric methane relative interpolar difference (rIPD) across the Last Glacial Maximum and Deglaciation. The rIPD was calculated using discrete, high-resolution methane measurements from the WAIS Divide, NEEM and GISP2 ice cores. Two independent IPD records were determined: One using NEEM and WAIS and one using GISP2 and WAIS. The dataset includes rIPD values calculated using both Greenland methane data both corrected and uncorrected for excess methane (Lee et al., 2020). The rIPD was calculated by smoothing each methane record and synchronizing them to the WD2014 gas age scale. 1-sigma rIPD uncertainties are included. This dataset also includes the output of the four-box troposphere model used to interpret the rIPD. For both excess methane-corrected records, the model output and 1-sigma uncertainty is provided for northern extratropical (30N - 90N) and total tropical (30S - 30N) sources in Tg yr-1. For the NEEM-derived rIPD, sections of the rIPD where atmospheric methane changed rapidly were deemed untrustworthy were removed from the dataset. Lee, J. E. et al. Excess methane in Greenland ice cores associated with high dust concentrations. Geochimica et cosmochimica acta 270, 409-430 (2020). | ["POINT(-112.05 -79.28)"] | ["POINT(-112.05 -79.28)"] | false | false |
Taylor Glacier CO2 Isotope Data 74-59 kyr
|
1245659 1245821 1246148 |
2022-08-23 | Menking, James; Shackleton, Sarah; Bauska, Thomas; Buffen, Aron; Brook, Edward J.; Barker, Stephen; Severinghaus, Jeffrey P.; Dyonisius, Michael; Petrenko, Vasilii; Menking, Andy |
Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive |
High-precision carbon isotope data (d13C-CO2) show atmospheric CO2 during Marine Isotope Stage 4 (MIS 4, ~70.5-59 ka) was controlled by a succession of millennial-scale processes. Enriched d13C-CO2 during peak glaciation suggests increased ocean carbon storage. Variations in d13C-CO2 in early MIS4 suggest multiple processes were active during CO2 drawdown, potentially including decreased land carbon and decreased Southern Ocean air-sea gas exchange superposed on increased ocean carbon storage. CO2 remained low during MIS 4 while d13C-CO2 fluctuations suggest changes in Southern Ocean and North Atlantic air-sea gas exchange. A 7 ppm increase in CO2 at the onset of Dansgaard-Oeschger event 19 (72.1 ka) and a 22 ppm increase in CO2 during late MIS 4 (Heinrich Stadial 6, ~63.5-60 ka) involved additions of isotopically light carbon to the atmosphere. The terrestrial biosphere and Southern Ocean air-sea gas exchange are possible sources, with the latter event also involving decreased ocean carbon storage. | ["POLYGON((161 -77.7,161.1 -77.7,161.2 -77.7,161.3 -77.7,161.4 -77.7,161.5 -77.7,161.6 -77.7,161.7 -77.7,161.8 -77.7,161.9 -77.7,162 -77.7,162 -77.71000000000001,162 -77.72,162 -77.73,162 -77.74,162 -77.75,162 -77.76,162 -77.77,162 -77.78,162 -77.78999999999999,162 -77.8,161.9 -77.8,161.8 -77.8,161.7 -77.8,161.6 -77.8,161.5 -77.8,161.4 -77.8,161.3 -77.8,161.2 -77.8,161.1 -77.8,161 -77.8,161 -77.78999999999999,161 -77.78,161 -77.77,161 -77.76,161 -77.75,161 -77.74,161 -77.73,161 -77.72,161 -77.71000000000001,161 -77.7))"] | ["POINT(161.5 -77.75)"] | false | false |
Preliminary nitrous oxide site preference isotopic data for last deglaciation from Taylor Glacier
|
1903681 |
2022-08-02 | Menking, Andy; Brook, Edward J. |
Deciphering Changes in Atmospheric Nitrous Oxide Concentration During the Last Ice Age Using the Intramolecular Site-Preference of Nitrogen Isotopes |
Measurements of the isotopic composition of atmospheric nitrous oxide from samples from the Taylor Glacier, Antarctica, spanning the last deglaciation (21-11 ka) and part of the last glacial period (40 to 36 ka). Data set includes the site preference of 15-N in N2O. A manuscript describing these data is currently in preparation. Data are referenced to in house air standards at OSU which are currently being cross calibrated with other laboratories. | ["POLYGON((161.745 -77.745,161.746 -77.745,161.747 -77.745,161.748 -77.745,161.749 -77.745,161.75 -77.745,161.751 -77.745,161.752 -77.745,161.753 -77.745,161.754 -77.745,161.755 -77.745,161.755 -77.74600000000001,161.755 -77.747,161.755 -77.748,161.755 -77.749,161.755 -77.75,161.755 -77.751,161.755 -77.752,161.755 -77.753,161.755 -77.75399999999999,161.755 -77.755,161.754 -77.755,161.753 -77.755,161.752 -77.755,161.751 -77.755,161.75 -77.755,161.749 -77.755,161.748 -77.755,161.747 -77.755,161.746 -77.755,161.745 -77.755,161.745 -77.75399999999999,161.745 -77.753,161.745 -77.752,161.745 -77.751,161.745 -77.75,161.745 -77.749,161.745 -77.748,161.745 -77.747,161.745 -77.74600000000001,161.745 -77.745))"] | ["POINT(161.75 -77.75)"] | false | false |
Major and trace element analyses of Eocene-Oligocene marine sediments from ODP Site 696, South Orkney Microcontinent
|
1743643 |
2022-06-22 | Passchier, Sandra; Hojnacki, Victoria; Li, Xiaona; States, Abbey; Lepp, Allison |
Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition |
This dataset contains measurements of major and trace elements on 190 samples of Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. The composition of detrital, biogenic and authigenic sediment components was assessed via whole rock geochemistry of sediment samples. Instrument analysis was completed at Montclair State University. | ["POINT(-42.933 -61.849)"] | ["POINT(-42.933 -61.849)"] | false | false |
Particle-size distributions of Eocene-Oligocene sediment from ODP Site 696, South Orkney Microcontinent
|
1743643 |
2022-06-21 | Passchier, Sandra; Lepp, Allison; Horowitz Castaldo, Josie; Light, Jennifer |
Timing and Spatial Distribution of Antarctic Ice Sheet Growth and Sea-ice Formation across the Eocene-Oligocene Transition |
This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 696 drilled in 650 m water depth on the South Orkney Microcontinent. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Diatoms were generally either absent or present in trace amounts in the Eocene-Oligocene interval and were not removed. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive Index of 1.6 (Illite) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(-42.933 -61.849)"] | ["POINT(-42.933 -61.849)"] | false | false |
Physical and geochemical data from five sediment cores collected offshore Thwaites Glacier
|
1738942 |
2022-01-27 | Lepp, Allison |
NSF-NERC: THwaites Offshore Research (THOR) |
This dataset contains measurements from grain-size, x-ray fluorescence (XRF), and physical properties (including magnetic susceptibility, water content, and shear strength) analyses of five sediment cores collected offshore Thwaites Glacier during cruises NBP19-02 (cores KC04, KC08, and KC23) and NBP20-02 (cores KC33 and KC67). We estimate the cores, which are between 213.5 and 297.5 cm in length, reflect deposition during the last ~10 kyr, consistent with published constraints of deglaciation of this region. Data are organized in Microsoft Excel spreadsheets and core locations are provided in a PDF. | ["POLYGON((-107.38 -74.64,-107.065 -74.64,-106.75 -74.64,-106.435 -74.64,-106.12 -74.64,-105.805 -74.64,-105.49 -74.64,-105.175 -74.64,-104.86 -74.64,-104.545 -74.64,-104.23 -74.64,-104.23 -74.683,-104.23 -74.726,-104.23 -74.769,-104.23 -74.812,-104.23 -74.855,-104.23 -74.898,-104.23 -74.941,-104.23 -74.984,-104.23 -75.027,-104.23 -75.07,-104.545 -75.07,-104.86 -75.07,-105.175 -75.07,-105.49 -75.07,-105.805 -75.07,-106.12 -75.07,-106.435 -75.07,-106.75 -75.07,-107.065 -75.07,-107.38 -75.07,-107.38 -75.027,-107.38 -74.984,-107.38 -74.941,-107.38 -74.898,-107.38 -74.855,-107.38 -74.812,-107.38 -74.769,-107.38 -74.726,-107.38 -74.683,-107.38 -74.64))"] | ["POINT(-105.805 -74.855)"] | false | false |
Pennell Trough, Ross Sea bathymetry and glacial landforms
|
1246353 1745043 1745055 |
2021-10-04 | Greenwood, Sarah; Munevar Garcia, Santiago; Eareckson, Elizabeth; Anderson, John; Prothro, Lindsay; Simkins, Lauren |
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. |
Bathymetry from multibeam echo sounding data in Pennell Trough, Ross Sea, Antarctica 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 a 1°×1° beam width, swath angular coverage set to 62°×62°, and 30-60% overlap between survey lines. All raw, ping-edited geophysical data collected on NBP15-02 can be accessed using the Marine Geoscience Data System (Cruise DOI: 10.7284/901477). The bathymetry dataset here is gridded at 20-m resolution with a water depth-dependent vertical resolution on the order of decimeters. Two shapefiles are provided for ice-marginal landforms and meltwater landforms observable in the bathymetry data. The purpose of collecting the bathymetry data on cruise NBP15-02 was to better understand the glacial history of the Ross Sea, and the dataset, inclusive of bathymetry data and shapefiles of glacial landforms, from Pennell Trough are used to understand impacts on subglacial channel morphology and organization during the deglaciation of the region following the Last Glacial Maximum. The published dataset was used and analyzed in the article "Topographic controls on channelized meltwater in the subglacial environment" by Simkins, L.M., Greenwood, S.L., Munevar Garcia, S., Eareckson, E.A., Anderson, J.B., and Prothro, L.O, which was published in Geophysical Research Letters in 2021 (DOI: 10.1029/2021GL094678). | ["POLYGON((174 -75,174.4 -75,174.8 -75,175.2 -75,175.6 -75,176 -75,176.4 -75,176.8 -75,177.2 -75,177.6 -75,178 -75,178 -75.2,178 -75.4,178 -75.6,178 -75.8,178 -76,178 -76.2,178 -76.4,178 -76.6,178 -76.8,178 -77,177.6 -77,177.2 -77,176.8 -77,176.4 -77,176 -77,175.6 -77,175.2 -77,174.8 -77,174.4 -77,174 -77,174 -76.8,174 -76.6,174 -76.4,174 -76.2,174 -76,174 -75.8,174 -75.6,174 -75.4,174 -75.2,174 -75))"] | ["POINT(176 -76)"] | false | false |
Particle-size distributions of Eocene-Oligocene sediment from ODP Site 742, Prydz Bay
|
1245283 |
2021-06-21 | Passchier, Sandra; Ciarletta, Daniel |
The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin |
This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 742 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(75.4045 -67.549667)"] | ["POINT(75.4045 -67.549667)"] | false | false |
Particle-size distributions of Eocene sediment from ODP Site 1166, Prydz Bay
|
1245283 |
2021-06-21 | Passchier, Sandra; Ciarletta, Daniel |
The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin |
This dataset contains measurements of terrigenous particle-size distributions on Eocene sediment from Ocean Drilling Program Site 1166 in Prydz Bay. Carbonate and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(74.787 -67.696167)"] | ["POINT(74.787 -67.696167)"] | false | false |
Particle-size distributions of Eocene-Oligocene sediment from ODP Site 739, Prydz Bay
|
1245283 |
2021-06-21 | Passchier, Sandra; Ciarletta, Daniel |
The Stratigraphic Expression of the Onset of Glaciation in Eocene-Oligocene Successions on the Antarctic Continental Margin |
This dataset contains measurements of terrigenous particle-size distributions on Eocene-Oligocene sediment from Ocean Drilling Program Site 739 in Prydz Bay. Carbonate, and organic matter were removed through addition of 10mL aliquots of 30% H2O2, 2mL aliquots of 10% HCl to ~50-100mL suspension on a hot plate. Dispersion was through heating with sodium pyrophosphate. Samples were measured on a Malvern Mastersizer 2000 with a Hydro 2000MU (A) accessory, using a Refractive index of 1.544 (Quartz) and an absorption coefficient of 0.9. Results are in (vol. %) per size class, with diameter range equivalent to the diameter of spheres with the same volume as measured particles. | ["POINT(75.081833 -67.276167)"] | ["POINT(75.081833 -67.276167)"] | false | false |
Multi-site ice core Krypton stable isotope ratios
|
1543229 1543267 |
2020-10-22 | Buizert, Christo; Shackleton, Sarah; Severinghaus, Jeffrey P.; Brook, Edward J.; Baggenstos, Daniel; Bereiter, Bernhard; Etheridge, David; Bertler, Nancy; Pyne, Rebecca L.; Mulvaney, Robert; Mosley-Thompson, Ellen |
Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last
deglaciation |
Stable isotope ratios of atmospheric krypton, argon, nitrogen and oxygen were measured in late-Holocene ice core samples from nine sites in Antarctica and Greenland, for the purpose of calibrating the Kr-86 excess proxy as defined in Buizert and Severinghaus (2016). | ["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 |
Roosevelt Island Ice Core Time Scale and Associated Data
|
0944021 |
2020-07-13 | Brook, Edward J.; Lee, James |
Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island |
Data archived here were used to create the Roosevelt Island Ice Core gas age and ice age time scales. Data include methane concentrations, nitrogen and oxygen isotope ratios of N2 and O2, total air content and the D/H ratio of the ice. Derived products included here include ice age and gas age time scales. | ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"] | ["POINT(-162 -79.25)"] | false | false |
Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation and Deep Core Results
|
1245659 |
2020-02-28 | Petrenko, Vasilii; Dyonisius, Michael |
Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive |
This data set contains measurements of 14CH4 and 14CO in ice cores from Taylor Glacier, Antarctica. This includes measurements in ice from the last deglaciation (18 - 8 kyr), for the purposes of paleoatmospheric 14CH4 reconstruction. The data set also includes measurements in older ice (50 - 70 kyr) from a deep ice core, made for the purposes of studying in situ cosmogenic 14C production in ice. All data are in excel format. | ["POINT(161.71353 -77.75855)"] | ["POINT(161.71353 -77.75855)"] | false | false |
Cosmogenic nuclide data from glacial deposits along the Liv Glacier coast
|
1443346 |
2019-11-21 | Stone, John |
Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment |
This data set contains measurements of cosmic-ray-produced Be-10 in quartz from glacial erratics and bedrock at sites along and adjacent to Liv Glacier and Amundsen Glacier in the southern Transantarctic Mountains. Samples were collected during the 2016-17 and 2017-18 field seasons working from remote camps along the coast. Locations were determined by hand-held GPS. Elevations are based on barometric altimetry corrected for daily drift and referenced to precise (geodetic) GPS benchmarks established over a range of altitudes at each site. Horizon geometry and the resulting topographic shielding of the cosmic ray flux was determined from vertically-oriented full-sky (fisheye) photographs at each sample location. Samples were processed at the University of Washington Cosmogenic Nuclide Laboratory using established procedures for mineral separation, dissolution, beryllium extraction and purification, described at http://depts.washington.edu/cosmolab/chem.shtml. Beryllium isotope ratios were measured at the Lawrence Livermore Center for Accelerator Mass Spectrometry (LLNL-CAMS) relative to the KNSTD-Be-01-5-4 standard, assuming a standard Be-10/Be-9 ratio of 2.851E-12 (07KNSTD normalization). Data are reported as input for the online CRONUS cosmogenic nuclide calculator (V3, current at the time of submission in November 2019). Exposure ages can be obtained by entering the data into the CRONUS calculator, at: http://hess.ess.washington.edu/math/v3/v3_age_in.html . Data for each sample consists of two lines of input parameters, as follows: {Sample_name, Latitude (DD), Longitude (DD), Altitude (m asl), Scaling_function, Thickness (cm), Density (g/cm^3), Horizon_correction, Erosion_rate (cm/yr), Year_sampled} {Sample_name, Nuclide (in this case Be-10), Target_mineral (quartz), Be-10_concentration (atom/g), Error_Be-10_concentration (atom/g), Normalization} Further information about the V3 input format is given at: http://hess.ess.washington.edu/math/docs/v3/v3_input_explained.html | ["POLYGON((-174 -84.5,-172.4 -84.5,-170.8 -84.5,-169.2 -84.5,-167.6 -84.5,-166 -84.5,-164.4 -84.5,-162.8 -84.5,-161.2 -84.5,-159.6 -84.5,-158 -84.5,-158 -84.63,-158 -84.76,-158 -84.89,-158 -85.02,-158 -85.15,-158 -85.28,-158 -85.41,-158 -85.54,-158 -85.67,-158 -85.8,-159.6 -85.8,-161.2 -85.8,-162.8 -85.8,-164.4 -85.8,-166 -85.8,-167.6 -85.8,-169.2 -85.8,-170.8 -85.8,-172.4 -85.8,-174 -85.8,-174 -85.67,-174 -85.54,-174 -85.41,-174 -85.28,-174 -85.15,-174 -85.02,-174 -84.89,-174 -84.76,-174 -84.63,-174 -84.5))"] | ["POINT(-166 -85.15)"] | false | false |
Liv and Amundsen Glacier Radiocarbon Data
|
1443248 |
2019-09-05 | Hall, Brenda |
Collaborative Research: High-resolution Reconstruction of Holocene Deglaciation in the Southern Ross Embayment |
["POLYGON((-170 -84,-168 -84,-166 -84,-164 -84,-162 -84,-160 -84,-158 -84,-156 -84,-154 -84,-152 -84,-150 -84,-150 -84.16,-150 -84.32,-150 -84.48,-150 -84.64,-150 -84.8,-150 -84.96,-150 -85.12,-150 -85.28,-150 -85.44,-150 -85.6,-152 -85.6,-154 -85.6,-156 -85.6,-158 -85.6,-160 -85.6,-162 -85.6,-164 -85.6,-166 -85.6,-168 -85.6,-170 -85.6,-170 -85.44,-170 -85.28,-170 -85.12,-170 -84.96,-170 -84.8,-170 -84.64,-170 -84.48,-170 -84.32,-170 -84.16,-170 -84))"] | ["POINT(-160 -84.8)"] | false | false | |
Noble Gas Data from recent ice in Antarctica for 86Kr problem
|
1543229 |
2019-08-02 | Severinghaus, Jeffrey P.; Shackleton, Sarah |
Collaborative research: Kr-86 as a proxy for barometric pressure variability and movement of the SH westerlies during the last
deglaciation |
This data comprises a survey of Recent ice from multiple sites in Antarctica using shallow ice cores to examine noble gas values in ice that nominally has the same Mean Ocean Temperature as today. The goal is to elucidate fractionation that occurs in the firn before air is trapped in bubbles in the ice, by making the assumption that the atmosphere noble gas content has not changed since this air was trappped. The ages of the air samples are typically early Industrial Revolution or late Holocene. | ["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 |
Roosevelt Island Borehole Optical Televiewer logs
|
0943466 |
2018-02-13 | Hawley, Robert L.; Clemens-Sewall, David |
Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island |
A Borehole Optical Televiewer (OPTV) uses a conical mirror and scanning electronics to record a continuous 360-degree image of the borehole wall. An inclinometer and magnetometer allow the image to be 'unwrapped' and resented as a rectangular image, which shows the visible features of the wall oriented to magnetic north. This dataset includes both the raw bitmap (bmp) image data from the televiewer, as well as proprietary WellCad format (wcl) files. The WellCad format files contain the inclinometry, orientation, and temperature data in addition to the imagery data. Wellcad files can be viewed with a free wellcad file reader available from https://www.alt.lu/downloads.htm. This dataset includes OPTV logs from each of two seasons, November 2013 and 2014. The logs are of the 760 m deep hole drilled by the RICE project, a NZ-USA partnership. | ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"] | ["POINT(-162 -79.25)"] | false | false |
Roosevelt Island Borehole Firn temperatures
|
0943466 |
2018-02-13 | Hawley, Robert L.; Clemens-Sewall, David; Giese, Alexandra |
Collaborative Research: Deglaciation of the Ross Sea Embayment - constraints from Roosevelt Island |
These data are firn temperatures, measured by a meteorological station placed at Roosevelt Island. Thermistors were placed at multiple depths through the upper 20 meters of firn and measured through the course of roughly one year. | ["POLYGON((-163 -79,-162.8 -79,-162.6 -79,-162.4 -79,-162.2 -79,-162 -79,-161.8 -79,-161.6 -79,-161.4 -79,-161.2 -79,-161 -79,-161 -79.05,-161 -79.1,-161 -79.15,-161 -79.2,-161 -79.25,-161 -79.3,-161 -79.35,-161 -79.4,-161 -79.45,-161 -79.5,-161.2 -79.5,-161.4 -79.5,-161.6 -79.5,-161.8 -79.5,-162 -79.5,-162.2 -79.5,-162.4 -79.5,-162.6 -79.5,-162.8 -79.5,-163 -79.5,-163 -79.45,-163 -79.4,-163 -79.35,-163 -79.3,-163 -79.25,-163 -79.2,-163 -79.15,-163 -79.1,-163 -79.05,-163 -79))"] | ["POINT(-162 -79.25)"] | false | false |
Region Climate Model Output Plio-Pleistocene
|
1245899 |
2018-01-16 | Kowalewski, Douglas |
Collaborative Research: West Antarctic Ice Sheet stability, Alpine Glaciation, and Climate Variability: a Terrestrial Perspective from Cosmogenic-nuclide Dating in McMurdo Sound |
Data here is output from regional climate modeling to shed light on the range of possible environmental conditions in the McMurdo region during periods of grounded ice expansion and recession during the Plio-Pleistocene. | ["POLYGON((160 -70,168 -70,176 -70,184 -70,192 -70,200 -70,208 -70,216 -70,224 -70,232 -70,240 -70,240 -71.5,240 -73,240 -74.5,240 -76,240 -77.5,240 -79,240 -80.5,240 -82,240 -83.5,240 -85,232 -85,224 -85,216 -85,208 -85,200 -85,192 -85,184 -85,176 -85,168 -85,160 -85,160 -83.5,160 -82,160 -80.5,160 -79,160 -77.5,160 -76,160 -74.5,160 -73,160 -71.5,160 -70))"] | ["POINT(-160 -77.5)"] | 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 |
Hatherton Glacier Radiocarbon Data
|
1246170 |
2017-10-23 | Hall, Brenda |
Collaborative Research: Assessing the Antarctic Contribution to Sea-level Changes during the Last Deglaciation: Constraints from Darwin Glacier |
Hatherton Glacier Radiocarbon Data | ["POLYGON((155.4 -79.8,155.54 -79.8,155.68 -79.8,155.82 -79.8,155.96 -79.8,156.1 -79.8,156.24 -79.8,156.38 -79.8,156.52 -79.8,156.66 -79.8,156.8 -79.8,156.8 -79.82,156.8 -79.84,156.8 -79.86,156.8 -79.88,156.8 -79.9,156.8 -79.92,156.8 -79.94,156.8 -79.96,156.8 -79.98,156.8 -80,156.66 -80,156.52 -80,156.38 -80,156.24 -80,156.1 -80,155.96 -80,155.82 -80,155.68 -80,155.54 -80,155.4 -80,155.4 -79.98,155.4 -79.96,155.4 -79.94,155.4 -79.92,155.4 -79.9,155.4 -79.88,155.4 -79.86,155.4 -79.84,155.4 -79.82,155.4 -79.8))"] | ["POINT(156.1 -79.9)"] | false | false |
10Be and 14C data from northern Antarctic Peninsula
|
1142002 |
2017-09-16 | Kaplan, Michael |
Terrestrial Geological Context for Glacier Change in the Northeast Antarctica Peninsula |
These are data sets obtained with the supported award. The ages concern the histories of glaciers, ice sheets, and general cryospheric and climatic activities of the northern Antarctic Peninsula and surrounding area.They cover periods from prior to the last global glacial maximum (stage 3 and older?) as well as since deglaciation. | ["POLYGON((-58 -63.7,-57.95 -63.7,-57.9 -63.7,-57.85 -63.7,-57.8 -63.7,-57.75 -63.7,-57.7 -63.7,-57.65 -63.7,-57.6 -63.7,-57.55 -63.7,-57.5 -63.7,-57.5 -63.73,-57.5 -63.76,-57.5 -63.79,-57.5 -63.82,-57.5 -63.85,-57.5 -63.88,-57.5 -63.91,-57.5 -63.94,-57.5 -63.97,-57.5 -64,-57.55 -64,-57.6 -64,-57.65 -64,-57.7 -64,-57.75 -64,-57.8 -64,-57.85 -64,-57.9 -64,-57.95 -64,-58 -64,-58 -63.97,-58 -63.94,-58 -63.91,-58 -63.88,-58 -63.85,-58 -63.82,-58 -63.79,-58 -63.76,-58 -63.73,-58 -63.7))"] | ["POINT(-57.75 -63.85)"] | false | false |
Fluorescence spectroscopy data from the West Antarctic Ice Sheet (WAIS) Divide ice core, WDC06A
|
0839075 |
2017-03-06 | Priscu, John; D'Andrilli, Juliana |
Collaborative Research: Integrated High Resolution Chemical and Biological Measurements on the Deep WAIS Divide Core |
This data set include depth (WDC06A-7 dating) and fluorescence intensity measurements for five fluorophore regions (A, C, M, B, and T) commonly found in natural organic matter. Data from 1300-1700m, 1700-2100m, and 2100-2700m correspond to the early Holocene, deglaciation period, and the Last Glacial Maximum. | ["POINT(-112.08648 -79.46763)"] | ["POINT(-112.08648 -79.46763)"] | false | false |
Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica
|
0839031 |
2016-01-01 | Severinghaus, Jeffrey P. |
Collaborative Research: A "Horizontal Ice Core" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica |
This award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the 'clathrate hypothesis' that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (>1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a 'horizontal ice core' would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica. | ["POINT(161.71965 -77.76165)"] | ["POINT(161.71965 -77.76165)"] | false | false |
The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive
|
1245821 |
2016-01-01 | Brook, Edward J. |
Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive |
This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, and delta 18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, delta 13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of delta 13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica. | ["POINT(162.167 -77.733)"] | ["POINT(162.167 -77.733)"] | false | false |
Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling
|
1142162 |
2016-01-01 | Stone, John |
Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling |
This award supports a reconnaissance geological and radar-sounding study of promising sites in West Antarctica for a future project to measure cosmogenic nuclides in subglacial bedrock. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain the highest possible surface detail. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public. | ["POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))"] | ["POINT(-94.64 -81.755)"] | false | false |
Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation
|
1043018 |
2015-12-03 | Pollard, David |
Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea |
Ice-sheet model output of Antarctic Ice Sheet simulations spanning 30,000 years BP to 5000+ years in the future. | ["POINT(-85 -82)"] | ["POINT(-85 -82)"] | false | false |
A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea
|
1043485 |
2015-01-01 | Kurz, Mark D.; Curtice, Josh |
Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea |
This award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation. | ["POLYGON((163.4 -77.47989,163.9848 -77.47989,164.5696 -77.47989,165.1544 -77.47989,165.7392 -77.47989,166.324 -77.47989,166.9088 -77.47989,167.4936 -77.47989,168.0784 -77.47989,168.6632 -77.47989,169.248 -77.47989,169.248 -77.565701,169.248 -77.651512,169.248 -77.737323,169.248 -77.823134,169.248 -77.908945,169.248 -77.994756,169.248 -78.080567,169.248 -78.166378,169.248 -78.252189,169.248 -78.338,168.6632 -78.338,168.0784 -78.338,167.4936 -78.338,166.9088 -78.338,166.324 -78.338,165.7392 -78.338,165.1544 -78.338,164.5696 -78.338,163.9848 -78.338,163.4 -78.338,163.4 -78.252189,163.4 -78.166378,163.4 -78.080567,163.4 -77.994756,163.4 -77.908945,163.4 -77.823134,163.4 -77.737323,163.4 -77.651512,163.4 -77.565701,163.4 -77.47989))"] | ["POINT(166.324 -77.908945)"] | false | false |
LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals
|
0902957 |
2011-01-01 | Robinson, Laura |
LGM and Deglacial Radiocarbon from U-series Dated Drake Passage Deep-sea Corals |
The proposal seeks funds to continue a follow-up analytical work of deep-sea corals collected in the Drake Passage during a research cruise. The project's goal is paleo-climate research looking to constrain the depth structure and time evolution of the radiocarbon content of the Southern Ocean during the glacial and deglaciation. Radiocarbon is a versatile tracer of past climate; its radioactive decay provides an internal clock with which to assess the rates of processes, and it can be used to trace the movement of carbon through the Earth's system. It enters the ocean through air-sea gas exchange, so processes that limits this will, therefore, reduce the radiocarbon content of both surface and deep waters. The Southern Ocean is a critical location for exchange of heat and carbon between the deep-ocean and atmospheric reservoirs, and the deep waters formed there fill large volumes of the global deep and intermediate oceans. As strong currents tend to scour away sediments, carbonate preservation is limited, and radiocarbon reservoir ages are poorly constrained, many traditional paleoceanographic techniques become impractical. It is proposed to alleviate these difficulties analyzing the chemical composition of deep-sea coral skeletons. Their aragonitic skeletons can be precisely dated using U-series decay, and when coupled with radiocarbon analyses will allow to calculate the C14/C12 ratio of the past water column. | ["POLYGON((-70.5 -54.5,-66.95 -54.5,-63.4 -54.5,-59.85 -54.5,-56.3 -54.5,-52.75 -54.5,-49.2 -54.5,-45.65 -54.5,-42.1 -54.5,-38.55 -54.5,-35 -54.5,-35 -55.2,-35 -55.9,-35 -56.6,-35 -57.3,-35 -58,-35 -58.7,-35 -59.4,-35 -60.1,-35 -60.8,-35 -61.5,-38.55 -61.5,-42.1 -61.5,-45.65 -61.5,-49.2 -61.5,-52.75 -61.5,-56.3 -61.5,-59.85 -61.5,-63.4 -61.5,-66.95 -61.5,-70.5 -61.5,-70.5 -60.8,-70.5 -60.1,-70.5 -59.4,-70.5 -58.7,-70.5 -58,-70.5 -57.3,-70.5 -56.6,-70.5 -55.9,-70.5 -55.2,-70.5 -54.5))"] | ["POINT(-52.75 -58)"] | false | false |
Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica
|
0440954 |
2009-01-01 | Miller, Molly |
Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica |
This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate. In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems. | ["POLYGON((159 -76.61667,159.05 -76.61667,159.1 -76.61667,159.15 -76.61667,159.2 -76.61667,159.25 -76.61667,159.3 -76.61667,159.35 -76.61667,159.4 -76.61667,159.45 -76.61667,159.5 -76.61667,159.5 -76.630003,159.5 -76.643336,159.5 -76.656669,159.5 -76.670002,159.5 -76.683335,159.5 -76.696668,159.5 -76.710001,159.5 -76.723334,159.5 -76.736667,159.5 -76.75,159.45 -76.75,159.4 -76.75,159.35 -76.75,159.3 -76.75,159.25 -76.75,159.2 -76.75,159.15 -76.75,159.1 -76.75,159.05 -76.75,159 -76.75,159 -76.736667,159 -76.723334,159 -76.710001,159 -76.696668,159 -76.683335,159 -76.670002,159 -76.656669,159 -76.643336,159 -76.630003,159 -76.61667))"] | ["POINT(159.25 -76.683335)"] | false | false |
Subglacial Topography: Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica
|
0230197 |
2006-10-25 | Holt, John W.; Blankenship, Donald D.; Morse, David L.; Vaughan, David G.; Corr, Hugh F. J.; Young, Duncan A. |
Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) |
This data set includes 5 km gridded data from the Airborne Geophysical Survey of the Amundsen Sea Embayment, Antarctica (AGASEA) conducted during the 2004-2005 austral summer. Investigators derived maps of the ice sheet surface and subglacial topography, which covers the entire catchments of both the Thwaites Glacier and the Pine Islands Glacier, from airborne survey systems mounted on a Twin Otter aircraft. The surveys had sufficient density to identify critical ice dynamic transitions within the Amundsen Sea Embayment (ASE). The ASE is the only major drainage to exhibit significant elevation change over the period of available satellite observations. Modeling of the Western Antarctic Ice Sheet (WAIS) deglaciation pinpointed the Pine Island Glacier and the Thwaites Glacier, which comprise a major portion of the ASE, as the most vulnerable features of the WAIS. Present knowledge of the ice thickness and subglacial boundary conditions in the ASE are insufficient to understand its evolution or its sensitivity to climatic change, and it is not yet determined whether these changes are evidence of ongoing deglaciation or simply a fluctuation that does not threaten the equilibrium of the ice sheet. This research will support the efforts of a community of United States and international researchers to assess the present and predict the future behavior of the ice sheet in the ASE. These data are available via FTP. | ["POLYGON((-134.9 -71.7,-129.86 -71.7,-124.82 -71.7,-119.78 -71.7,-114.74 -71.7,-109.7 -71.7,-104.66 -71.7,-99.62 -71.7,-94.58 -71.7,-89.54 -71.7,-84.5 -71.7,-84.5 -72.7,-84.5 -73.7,-84.5 -74.7,-84.5 -75.7,-84.5 -76.7,-84.5 -77.7,-84.5 -78.7,-84.5 -79.7,-84.5 -80.7,-84.5 -81.7,-89.54 -81.7,-94.58 -81.7,-99.62 -81.7,-104.66 -81.7,-109.7 -81.7,-114.74 -81.7,-119.78 -81.7,-124.82 -81.7,-129.86 -81.7,-134.9 -81.7,-134.9 -80.7,-134.9 -79.7,-134.9 -78.7,-134.9 -77.7,-134.9 -76.7,-134.9 -75.7,-134.9 -74.7,-134.9 -73.7,-134.9 -72.7,-134.9 -71.7))"] | ["POINT(-109.7 -76.7)"] | false | false |