USAP-DC

{"dp_type": "Dataset", "free_text": "Holocene"}

[{"awards": "1443386 Emslie, Steven; 2135695 Emslie, Steven", "bounds_geometry": null, "date_created": "Tue, 11 Mar 2025 00:00:00 GMT", "description": "We completed multiple-stable isotope analyses (d13C, d15N, and d34S) of Ad\u00e9lie penguin Pygoscelis adeliae chick-bone collagen to characterize differences in foraging behavior among 15 colony locations across the Ross Sea region. Foraging behavior was represented by d13C, d15N, and d34S values and classified into groups using k-means cluster analyses. Additionally, we report the first stable isotope values for the Ad\u00e9lie penguin colony on Sabrina Island, Balleny Islands. Cluster analyses revealed distinct isotopic signatures for the northernmost and central colonies; however, owing to spatial and temporal variability, isotopic signatures were not strong enough to distinguish the southernmost colonies. Results also indicated that d15N values increased with latitude (66\u201377\u00b0 S), corresponding to higher krill consumption at colonies that foraged in sensible heat polynyas or the open ocean and increased fish consumption for those foraging in latent heat polynyas to the south. Generally, d34S values are used to distinguish foraging grounds, specifically inshore/offshore foraging or foraging over the continental slope versus the continental shelf, in marine animals. Although the southern and central colonies currently forage along the continental shelf and the northern colonies forage over the shelf, slope, and/or open ocean, we found no significant difference in d34S values among colonies. While a positive correlation between d15N and d34S values was evident, d34S signatures did not exhibit distinct patterns specific to individual colonies or regions. The absence of a clear trend reflecting inshore/offshore foraging underscores the need for additional research to bridge this knowledge gap.", "east": null, "geometry": null, "keywords": "Adelie Penguin; Antarctica; Cryosphere; Foraging; Polynya; Pygoscelis Adeliae; Ross Sea; Stable Isotopes", "locations": "Antarctica; Ross Sea", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Emslie, Steven D.; Reaves, Megan; Powers, Shannon", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators; Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea", "projects": [{"proj_uid": "p0010388", "repository": "USAP-DC", "title": "Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea"}, {"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Stable isotopes of Adelie Penguin chick bone collagen", "uid": "601913", "west": null}, {"awards": "1443105 Steig, Eric; 1141839 Steig, Eric; 1443336 Osterberg, Erich; 1443397 Kreutz, Karl; 1443663 Cole-Dai, Jihong", "bounds_geometry": ["POINT(-99 -90)"], "date_created": "Wed, 20 Nov 2024 00:00:00 GMT", "description": "This dataset includes all major ion chemistry data from the South Pole Ice Core as well as sea salt sodium data resampled at annual resolution. The development of this dataset is discussed in Winski et al. 2021. The chloride, nitrate, sulfate, magnesium and calcium data have not yet been published, nor has any data prior to the Holocene. Please contact the dataset authors if you have questions.", "east": -99.0, "geometry": ["POINT(-99 -90)"], "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "persons": "Winski, Dominic A.", "project_titles": "Collaborative Research: A 1500m Ice Core from South Pole; Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole; Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements", "projects": [{"proj_uid": "p0010060", "repository": "USAP-DC", "title": "Collaborative Research: A 1500m Ice Core from South Pole"}, {"proj_uid": "p0010065", "repository": "USAP-DC", "title": "Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole"}, {"proj_uid": "p0010051", "repository": "USAP-DC", "title": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "South Pole Ice Core Sea Salt and Major Ions", "uid": "601851", "west": -99.0}, {"awards": "1443336 Osterberg, Erich; 1443397 Kreutz, Karl; 1443663 Cole-Dai, Jihong; 1443105 Steig, Eric; 1141839 Steig, Eric", "bounds_geometry": ["POINT(-89.16 -89.99)"], "date_created": "Mon, 18 Nov 2024 00:00:00 GMT", "description": "This dataset includes major ion and seasonal sea salt chemistry data from the South Pole Ice Core. Included are the raw major ion data, annually resolved mean, maximum and minimum sea salt sodium concentrations and centennially resolved principal components (discussed in Winski et al. (2021).", "east": -89.16, "geometry": ["POINT(-89.16 -89.99)"], "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "locations": "Antarctica; South Pole", "north": -89.99, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "persons": "Winski, Dominic A.", "project_titles": "Collaborative Research: A 1500m Ice Core from South Pole; Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole; Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements", "projects": [{"proj_uid": "p0010065", "repository": "USAP-DC", "title": "Collaborative Research: Record of the Triple-oxygen Isotope and Hydrogen Isotope Composition of Ice from an Ice Core at South Pole"}, {"proj_uid": "p0010051", "repository": "USAP-DC", "title": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements"}, {"proj_uid": "p0010060", "repository": "USAP-DC", "title": "Collaborative Research: A 1500m Ice Core from South Pole"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -89.99, "title": "South Pole Ice Core Holocene Major Ion Dataset", "uid": "601850", "west": -89.16}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((117 -66,119.9 -66,122.8 -66,125.7 -66,128.6 -66,131.5 -66,134.4 -66,137.3 -66,140.2 -66,143.1 -66,146 -66,146 -66.1,146 -66.2,146 -66.3,146 -66.4,146 -66.5,146 -66.6,146 -66.7,146 -66.8,146 -66.9,146 -67,143.1 -67,140.2 -67,137.3 -67,134.4 -67,131.5 -67,128.6 -67,125.7 -67,122.8 -67,119.9 -67,117 -67,117 -66.9,117 -66.8,117 -66.7,117 -66.6,117 -66.5,117 -66.4,117 -66.3,117 -66.2,117 -66.1,117 -66))"], "date_created": "Mon, 21 Oct 2024 00:00:00 GMT", "description": "Totten Glacier is the termination of the largest marine-based portion of the East Antarctic Ice Sheet, the Aurora Subglacial Basin. Yet little is known about the glacial evolution of the catchment and the factors influencing its present and past behavior. Due its remote location and heavy sea ice, the continental shelf in front of the Totten Glacier had not been comprehensively surveyed prior to this study. Satellite observations indicate that the Totten ice drainage system is thinning, and it has been hypothesized that this thinning is in response to undermelting by warm ocean waters over the continental shelf. While this process is observed elsewhere in Antarctica (e.g. the rapidly retreating Pine Island Glacier in West Antarctica), the Totten Glacier system is potentially Antarcticas most important glacial drainage system due to its large size; it is three times larger than any system in West Antarctica. \u003c/br\u003eThe main goals of this proposal were: \u003c/br\u003eTo generate multibeam bathymetric maps of the continental shelf proximal to the Totten Glacier system to understand the recent regional glacial history and to document the pathways, if any, for circumpolar deep water to move onto the shelf. \u003c/br\u003eTo conduct a physical oceanographic survey of the region proximal to the Totten Glacier system, to determine the presence, if any, of warm ocean waters over the continental shelf.\u003c/br\u003eTo conduct a seismic survey of the continental shelf to assess the long-term evolution of the glacial system in the Aurora Subglacial Basin.\u003c/br\u003eTo collect marine sediment cores to determine the regional deglacial to Holocene climate history and the influence of warm circumpolar deep water.", "east": 146.0, "geometry": ["POINT(131.5 -66.5)"], "keywords": "Antarctica; Cryosphere; Diatom; NBP1402; Totten Glacier", "locations": "Antarctica; Antarctica; Totten Glacier", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy; NBP1402 science party, ", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "NBP1402 diatom data", "uid": "601845", "west": 117.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POLYGON((-80 -59,-76.8 -59,-73.6 -59,-70.4 -59,-67.2 -59,-64 -59,-60.8 -59,-57.599999999999994 -59,-54.4 -59,-51.2 -59,-48 -59,-48 -60.6,-48 -62.2,-48 -63.8,-48 -65.4,-48 -67,-48 -68.6,-48 -70.2,-48 -71.8,-48 -73.4,-48 -75,-51.2 -75,-54.4 -75,-57.6 -75,-60.8 -75,-64 -75,-67.2 -75,-70.4 -75,-73.6 -75,-76.8 -75,-80 -75,-80 -73.4,-80 -71.8,-80 -70.2,-80 -68.6,-80 -67,-80 -65.4,-80 -63.8,-80 -62.2,-80 -60.6,-80 -59))"], "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "This dataset includes measurements of diatom-bound nitrogen isotopic composition (d15Ndb; \u2030 vs air), bulk sedimentary nitrogen isotopic composition (d15Nbulk; \u2030 vs air), and total nitrogen (wt%) from 81 Holocene and late deglacial-aged samples from ODP Site 1098B on the western Antarctic Peninsula.", "east": -48.0, "geometry": ["POINT(-64 -67)"], "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Geochemistry; Sediment", "locations": "Antarctic Peninsula; Antarctica", "north": -59.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel; Jones, Colin; Kelly, Roger; Robinson, Rebecca", "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": -75.0, "title": "Diatom-bound and bulk sedimentary N isotopes from ODP Site 1098, Western Antarctic Peninsula", "uid": "601816", "west": -80.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": ["POLYGON((100 -62,104.4 -62,108.8 -62,113.2 -62,117.6 -62,122 -62,126.4 -62,130.8 -62,135.2 -62,139.6 -62,144 -62,144 -64,144 -66,144 -68,144 -70,144 -72,144 -74,144 -76,144 -78,144 -80,144 -82,139.6 -82,135.2 -82,130.8 -82,126.4 -82,122 -82,117.6 -82,113.19999999999999 -82,108.8 -82,104.4 -82,100 -82,100 -80,100 -78,100 -76,100 -74,100 -72,100 -70,100 -68,100 -66,100 -64,100 -62))"], "date_created": "Tue, 13 Aug 2024 00:00:00 GMT", "description": "This dataset includes measurements of diatom-bound nitrogen isotopic composition (d15Ndb; \u2030 vs air), bulk sedimentary nitrogen isotopic composition (d15Nbulk; \u2030 vs air), and total nitrogen (wt%) from 121 samples from IODP Site U1357B in the Adelie Basin. The sediments are Holocene age (11 kyBP to present).", "east": 144.0, "geometry": ["POINT(122 -72)"], "keywords": "Antarctica; Cryosphere; Wilkes Land", "locations": "Wilkes Land; Antarctica", "north": -62.0, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel; Kelly, Roger; Robinson, Rebecca", "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": -82.0, "title": "Diatom-bound and bulk sedimentary nitrogen isotopes from IODP Site U1357", "uid": "601817", "west": 100.0}, {"awards": "2200448 Simms, Alexander", "bounds_geometry": null, "date_created": "Fri, 10 May 2024 00:00:00 GMT", "description": "Radiocarbon dating is arguably the most common method for dating Quaternary deposits. However, accurate age assignments using radiocarbon dating are dependent on knowing the radiocarbon reservoir. For the coastal waters across Antarctica, the radiocarbon reservoirs show significant variation, ranging from 700 to 6,000 years depending on the material dated and the period in question. In this study, we examine the radiocarbon reservoir age for the shallow waters of the Southern Ocean using 23 whale bones salvaged from whaling stations operating on or near the Western Antarctic Peninsula between 1904 and 1916. The species origin of the bones had been identified previously as humpback, fin, or blue whales using sequences of mitochondrial (mt)DNA. We find an average reservoir age of 1050 +/- 135 years for these 23 whale bones, with a \u003c100 year difference in the reservoir age value by species. A comparison between our results and other studies through the Holocene suggest that the Southern Ocean surface water radiocarbon reservoir age has not significantly changed for the last 14,000 years. Combining our new ages with existing data sets provides insight to the stability of the Southern Ocean marine radiocarbon reservoir age, enhancing our understanding of ocean ventilation and upwelling dynamics throughout the Holocene.", "east": null, "geometry": null, "keywords": "Antarctica; C-14; Cryosphere; Radiocarbon Dates; Whale Bone; Whales", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Divola, Claire; Simms, Alexander; Sremba, Angela; Baker, C. Scott; Friedlaender, Ari; Southon, John", "project_titles": "New constraints on 14C reservoirs around the Antarctic Peninsula and the Southern Ocean based on historically-harvested whale bones", "projects": [{"proj_uid": "p0010457", "repository": "USAP-DC", "title": "New constraints on 14C reservoirs around the Antarctic Peninsula and the Southern Ocean based on historically-harvested whale bones"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Constraining the Radiocarbon Reservoir Age for the Southern Ocean Using Whale Bones Salvaged from Early 20th Century Whaling Stations", "uid": "601784", "west": null}, {"awards": "0739512 Walker, Sally; 1745064 Perez-Huerta, Alberto; 1745057 Walker, Sally; 1745080 Gillikin, David", "bounds_geometry": null, "date_created": "Mon, 05 Feb 2024 00:00:00 GMT", "description": "Adamussium colbecki is a large thin-shelled scallop common in Antarctic waters and well represented in the fossil record. Shell nitrogen isotopes in carbonate bound organic matter (d15NCBOM) have the potential to record sea ice state over time. Recent studies illustrated that d15NCBOM values provide a similar proxy as soft tissue d15N values which are in turn are predicably related to food d15N values (Gillikin et al., 2017, GCA, 200, 55\u201366, doi: 10.1016/j.gca.2016.12.008). Sea-ice organic N should have higher d15N values compared to open water organics due to nitrate draw down in the ice (Fripiat et al., 2014, Global Biogeochem. Cycles, 28, 115\u2013130, doi:10.1002/2013GB004729). To test this hypothesis we analyzed A. colbecki shells from Explorers Cove and Bay of Sails, western McMurdo Sound, Antarctica. These sites have different sea ice states: persistent (multiannual) sea ice at Explorers Cove and annual sea ice (that melts out every year) at Bay of Sails. Six adults shells collected at these sites in 2008 (3 from each site) and two juveniles collected in 2016 from Explorers Cove were be serially sampled for d15NCBOM values from the growing shell margin to the umbo. d15NCBOM values from Explorers Cove with persistent sea ice cover were consistently higher (+10 \u00b1 0.7 \u2030) than those from Bay of Sails where the sea ice melts out every year (+8 \u00b1 0.5 \u2030; t-test p\u003c0.0001). d15NCBOM data from Mid- to Late Holocene shells that grew in these locations will also be presented. We posit that nitrogen isotopes in A. colbecki shells have a high potential to record sea ice cover.", "east": null, "geometry": null, "keywords": "Adamussium Colbecki; Antarctica; Biota; Carbon Isotopes; Explorers Cove; Nitrogen Isotopes; Oxygen Isotope; Scallop", "locations": "Explorers Cove; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Gillikin, David; Puhalski, Emma; Camarra, Steve; Cronin, Kelly; Verheyden, Anouk; Walker, Sally", "project_titles": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores; Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past", "projects": [{"proj_uid": "p0010238", "repository": "USAP-DC", "title": "Collaborative research: The Antarctic Scallop as Key to Paleoenvironments and Sea Ice Conditions: Understanding the Modern to Predict the Past"}, {"proj_uid": "p0000203", "repository": "USAP-DC", "title": "Collaborative Research: Linking Modern Benthic Communities and Taphonomic Processes to the Stratigraphic Record of Antarctic Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Nitrogen, carbon, and oxygen isotopes in the shell of the Antarctic scallop Adamussium colbecki as a proxy for sea ice cover in Antarctica.", "uid": "601764", "west": null}, {"awards": "1443585 Polito, Michael; 1443386 Emslie, Steven; 1826712 McMahon, Kelton; 1443424 McMahon, Kelton", "bounds_geometry": ["POLYGON((-180 -61.59,-168.969 -61.59,-157.938 -61.59,-146.90699999999998 -61.59,-135.876 -61.59,-124.845 -61.59,-113.814 -61.59,-102.783 -61.59,-91.752 -61.59,-80.72099999999999 -61.59,-69.69 -61.59,-69.69 -63.195,-69.69 -64.8,-69.69 -66.405,-69.69 -68.01,-69.69 -69.61500000000001,-69.69 -71.22,-69.69 -72.825,-69.69 -74.43,-69.69 -76.035,-69.69 -77.64,-80.721 -77.64,-91.752 -77.64,-102.783 -77.64,-113.814 -77.64,-124.845 -77.64,-135.876 -77.64,-146.90699999999998 -77.64,-157.938 -77.64,-168.969 -77.64,180 -77.64,179.02100000000002 -77.64,178.042 -77.64,177.063 -77.64,176.084 -77.64,175.10500000000002 -77.64,174.126 -77.64,173.147 -77.64,172.168 -77.64,171.18900000000002 -77.64,170.21 -77.64,170.21 -76.035,170.21 -74.43,170.21 -72.825,170.21 -71.22,170.21 -69.61500000000001,170.21 -68.01,170.21 -66.405,170.21 -64.8,170.21 -63.195,170.21 -61.59,171.18900000000002 -61.59,172.168 -61.59,173.147 -61.59,174.126 -61.59,175.10500000000002 -61.59,176.084 -61.59,177.063 -61.59,178.042 -61.59,179.02100000000002 -61.59,-180 -61.59))"], "date_created": "Tue, 09 Jan 2024 00:00:00 GMT", "description": "This data set contains measurements of nitrogen (\u03b415N) stable isotope values of twelve individual amino acids from modern and excavated eggshell of Ad\u00e9lie penguins (Pygoscelis adelidae) from multiple sites around the Antarctic Peninsula and Ross Sea regions of Antarctica. Stable isotope analyses were conducted using a gas chromatograph coupled to a continuous flow stable isotope ratio mass spectrometer. Radiocarbon dates of excavated eggshells were estimated using accelerator Mass Spectrometry (AMS) on bone, feather, and egg membrane tissues from the same ornithogenic layer as the eggshell and were completed at the Rafter Radiocarbon Laboratory and New Zealand (NZA), Beta Analytic, Inc. (Beta). All dates were corrected for the marine carbon reservoir effect and calibrated to calendar years before present (cal years BP) using a \u0394R of 750\u2009\u00b1\u200950 years and the MARINE13 calibration curve in Calib 7.0 (2\u03c3 range). \r\n\r\nThis data set indexes each individually analyzed eggshell sample with site (location), latitude, longitude, tissue used from radiocarbon dating, age of the sample, and nitrogen stable isotope values of individual amino acids. Details of the data set and all relevant methods are provided in Michelson et al. 2023 Limnol. Oceanogr. DOI:10.1002/lno.12446", "east": 170.21, "geometry": ["POINT(-129.74 -69.61500000000001)"], "keywords": "Adelie Penguin; Amino Acids; Antarctica; Antarctic Peninsula; Ross Sea; Stable Isotope Analysis; Trophic Position", "locations": "Ross Sea; Antarctic Peninsula; Antarctica", "north": -61.59, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Michelson, Chantel; Polito, Michael; Wonder, Michael; McCarthy, Matthew; Patterson, William; McMahon, Kelton; Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.64, "title": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions", "uid": "601760", "west": -69.69}, {"awards": "1851022 Fudge, Tyler", "bounds_geometry": ["POINT(123.33 -75.09)"], "date_created": "Fri, 22 Dec 2023 00:00:00 GMT", "description": "Volcanic deposition of sulfuric acid in ice cores is important both for understanding past volcanic activity and for synchronizing ice core timescales. Sulfuric acid has a low eutectic point, so it can potentially exist in liquid at grain boundaries and veins, accelerating chemical diffusion. A high effective diffusivity would allow post-depositional diffusion to obscure the climate history and the peak matching among older portions of ice cores. Here, we use records of sulfate from the EPICA Dome C (EDC) ice core to estimate the effective diffusivity of sulfuric acid in ice. We focus on EDC because multiple glacial-interglacial cycles are preserved, allowing analysis for long timescales and deposition in similar climates. We calculate the mean concentration gradient and the width of prominent volcanic events, and analyze the evolution of each with depth/age. We find the effective diffusivities for interglacials and glacial maximums to be 5 \u00b1 3 \u00d7 10-9 m2 a-1, an order of magnitude lower than a previous estimate derived from the Holocene portion of EDC (Barnes et al., 2003). The effective diffusivity may be even smaller if the bias from artificial smoothing from the sampling is accounted for. Effective diffusivity is not obviously affected by the ice temperature until about -10\u00b0C, 3000m depth, which is also where anomalous sulfate peaks begin to be observed (Traversi et al., 2009). Low effective diffusivity suggests that sulfuric acid is not readily diffusing in liquid-like veins in the upper portions of the Antarctic ice sheet and that records may be preserved in deep, old ice if the ice temperature remains well below the pressure melting point.", "east": 123.33, "geometry": ["POINT(123.33 -75.09)"], "keywords": "Antarctica", "locations": "Antarctica", "north": -75.09, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Fudge, T. J.; Severi, Mirko", "project_titles": "Collaborative Research: The Impact of Impurities and Stress State on Polycrystalline Ice Deformation", "projects": [{"proj_uid": "p0010211", "repository": "USAP-DC", "title": "Collaborative Research: The Impact of Impurities and Stress State on Polycrystalline Ice Deformation"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -75.09, "title": "EPICA Dome C Sulfate Data 7-3190m", "uid": "601759", "west": 123.33}, {"awards": null, "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Fri, 13 Oct 2023 00:00:00 GMT", "description": "This data set contains the VSMOW-SLAP d170, d180, and 170-excess data from the WAIS Divide Ice Core Project, Siple Dome and Taylor Dome, along with the published and VSMOW-SLAP normalized d170, d180, and 170-excess for Vostok [Landais et al.2008], EPICA Dome C and Talos Dome [Wrinkler et al.,2012]. The data cover the Last Glacial Maximum (25-20 ka), through the Early Holocene (12-9 ka) and into present-day (past 2 kyr).", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Delta 18O; Delta O-17; Epica Dome C; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Siple Dome; Talos Dome; Taylor Dome; Vostok", "locations": "Talos Dome; Siple Dome; Taylor Dome; Talos Dome; Epica Dome C; Vostok; Antarctica; Siple Dome; Taylor Dome; Epica Dome C", "north": -60.0, "nsf_funding_programs": null, "persons": "Steig, Eric J.; Schoenemann, Spruce", "project_titles": null, "projects": null, "repositories": null, "science_programs": "WAIS Divide Ice Core", "south": -90.0, "title": "VSMOW-SLAP d170, d180, and 17O-excess data from WAIS Divide Ice Core Project, Siple Dome and Taylor Dome", "uid": "601743", "west": -180.0}, {"awards": "1738989 Venturelli, Ryan", "bounds_geometry": ["POINT(-110.96038 -75.21526)"], "date_created": "Mon, 10 Jul 2023 00:00:00 GMT", "description": "Included in this dataset are in situ carbon-14 concentrations for a series of bedrock cores recovered from the subglacial extension of Kay Peak, a grounding-line-proximal ridge of the volcanic edifice Mount Murphy (near Thwaites and Pope glaciers). Concentrations measured in these bedrock samples have been used in the associated publication to demonstrate that the Thwaites-Pope glacier system was thinner in the Holocene than it is today. ", "east": -110.96038, "geometry": ["POINT(-110.96038 -75.21526)"], "keywords": "Antarctica; Cosmogenic Radionuclides; Mount Murphy; Subglacial Bedrock", "locations": "Mount Murphy; Antarctica", "north": -75.21526, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Venturelli, Ryan; Goehring, Brent; Balco, Gregory", "project_titles": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System", "projects": [{"proj_uid": "p0010165", "repository": "USAP-DC", "title": "NSF-NERC: Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Thwaites (ITGC)", "south": -75.21526, "title": "In situ 14C data from a subglacial bedrock core near Pope and Thwaites glaciers", "uid": "601705", "west": -110.96038}, {"awards": "1644197 Simms, Alexander", "bounds_geometry": null, "date_created": "Mon, 19 Dec 2022 00:00:00 GMT", "description": "This dataset provides the raw and processed ground-penetrating radar (GPR) data collected on Joinville Island in the Antarctic Peninsula. ", "east": null, "geometry": null, "keywords": "Antarctica; Joinville Island", "locations": "Antarctica; Joinville Island", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Simms, Alexander", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Ground Penetrating Radar Profiles from Beaches on Joinville Island, Antarctic Peninsula", "uid": "601632", "west": null}, {"awards": "1644197 Simms, Alexander", "bounds_geometry": null, "date_created": "Mon, 19 Dec 2022 00:00:00 GMT", "description": "This dataset consists of the location, elevation, and age of samples obtained from Joinville Island along the Antarctic Peninsula", "east": null, "geometry": null, "keywords": "Antarctica; Joinville Island; Raised Beaches; Sea Level", "locations": "Antarctica; Joinville Island", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Simms, Alexander", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Radiocarbon Ages from Beaches on Joinville Island, Antarctic Peninsula", "uid": "601634", "west": null}, {"awards": "1644197 Simms, Alexander", "bounds_geometry": null, "date_created": "Mon, 19 Dec 2022 00:00:00 GMT", "description": "This dataset includes ground-penetrating radar (GPR) data collected on Livingston Island in the Antarctic Peninsula.", "east": null, "geometry": null, "keywords": "Antarctica; Joinville Island", "locations": "Antarctica; Joinville Island", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Simms, Alexander", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Ground-Penetrating Radar data from Livingston Island in the Antarctic Peninsula", "uid": "601633", "west": null}, {"awards": "1043092 Steig, Eric; 1807522 Jones, Tyler", "bounds_geometry": ["POINT(-112.085 -79.467)"], "date_created": "Thu, 01 Sep 2022 00:00:00 GMT", "description": "We analyzed a continuous record of water-isotope ratios from the West Antarctic Ice Sheet (WAIS) Divide ice core to reveal summer and winter temperature changes through the last 11,000 years. ", "east": -112.085, "geometry": ["POINT(-112.085 -79.467)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Seasonality; Seasonal Temperatures; Temperature; Water Isotopes; West Antarctic Ice Sheet", "locations": "Antarctica; West Antarctic Ice Sheet", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "persons": "Jones, Tyler R.", "project_titles": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core; Collaborative Research: Targeted resampling of deep polar ice cores using information theory", "projects": [{"proj_uid": "p0000078", "repository": "USAP-DC", "title": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core"}, {"proj_uid": "p0010100", "repository": "USAP-DC", "title": "Collaborative Research: Targeted resampling of deep polar ice cores using information theory"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Seasonal temperatures in West Antarctica during the Holocene ", "uid": "601603", "west": -112.085}, {"awards": "1643868 DeWitt, Regina; 1644197 Simms, Alexander", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "detailed results for rock and sediment OSL ages; De calculation; dose rate calculation, fading, signal measurement", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Joinville Island; Antarctica; Livingston Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Joinville and Livingston Islands - rock and sediment OSL ages", "uid": "601534", "west": -65.0}, {"awards": "1643868 DeWitt, Regina; 1644197 Simms, Alexander", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "raw OSL data for rock and sediment samples collected on Joinville and Livingston Islands", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Joinville Island; Antarctica; Livingston Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "OSL data - Joinville and Livingston Islands - Raw data", "uid": "601532", "west": -65.0}, {"awards": "1644197 Simms, Alexander; 1643868 DeWitt, Regina", "bounds_geometry": ["POLYGON((-65 -61,-64 -61,-63 -61,-62 -61,-61 -61,-60 -61,-59 -61,-58 -61,-57 -61,-56 -61,-55 -61,-55 -61.4,-55 -61.8,-55 -62.2,-55 -62.6,-55 -63,-55 -63.4,-55 -63.8,-55 -64.2,-55 -64.6,-55 -65,-56 -65,-57 -65,-58 -65,-59 -65,-60 -65,-61 -65,-62 -65,-63 -65,-64 -65,-65 -65,-65 -64.6,-65 -64.2,-65 -63.8,-65 -63.4,-65 -63,-65 -62.6,-65 -62.2,-65 -61.8,-65 -61.4,-65 -61))"], "date_created": "Fri, 11 Mar 2022 00:00:00 GMT", "description": "sediment and rock samples were collected on Joinville and Livingston Islands for OSL dating; feldspar separates were prepared; data set includes Electron microprobe analysis of selected feldspar extracts; includes bmp and tif with elemental maps plus elemental concentrations and Ca:Na:K ratios for feldspar analysis", "east": -55.0, "geometry": ["POINT(-60 -63)"], "keywords": "Antarctica; Geochronology; Joinville Island; Livingston Island; OSL dating; Raised Beaches", "locations": "Livingston Island; Antarctica; Joinville Island", "north": -61.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "DeWitt, Regina", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "Electron Microprobe Analysis of feldspar separates from rock and sediment OSL samples from Joinville and Livingston Island Beaches", "uid": "601531", "west": -65.0}, {"awards": "1443585 Polito, Michael; 1443386 Emslie, Steven; 1443424 McMahon, Kelton; 1826712 McMahon, Kelton", "bounds_geometry": ["POLYGON((-37.33 -54.05,-37.192 -54.05,-37.054 -54.05,-36.916 -54.05,-36.778 -54.05,-36.64 -54.05,-36.502 -54.05,-36.364 -54.05,-36.226 -54.05,-36.088 -54.05,-35.95 -54.05,-35.95 -54.107,-35.95 -54.164,-35.95 -54.221,-35.95 -54.278,-35.95 -54.335,-35.95 -54.392,-35.95 -54.449,-35.95 -54.506,-35.95 -54.563,-35.95 -54.62,-36.088 -54.62,-36.226 -54.62,-36.364 -54.62,-36.502 -54.62,-36.64 -54.62,-36.778 -54.62,-36.916 -54.62,-37.054 -54.62,-37.192 -54.62,-37.33 -54.62,-37.33 -54.563,-37.33 -54.506,-37.33 -54.449,-37.33 -54.392,-37.33 -54.335,-37.33 -54.278,-37.33 -54.221,-37.33 -54.164,-37.33 -54.107,-37.33 -54.05))"], "date_created": "Thu, 13 Jan 2022 00:00:00 GMT", "description": "This data set contains radiometric dating measurements from two aquatic sediment cores excavated from two separate sites (Salisbury Plain and Gold Harbor) on South Georgia Island in February 2019. It also contains biological and geochemical sediment proxy values from both sediment cores, including total carbon (%), total nitrogen (%), number of penguin feathers and eggshell fragments, number of seal hairs, and \u03b413C and \u03b415N stable isotope values. Cores were sectioned at 1cm intervals, and radiometric dating analyses were conducted on sediment fractions \u003c850 \u00b5m by measuring for 210Pb and 226Ra (via 214Pb) by direct gamma counting using the high purity germanium planar detector in the Marine Geochemistry Laboratory at Louisiana State University (LSU). The 210Pbex profiles were used to calculate sedimentation rates using a steady state model that assumes constant rate of supply and constant sedimentation rate (Maiti et al., 2010). Geochemical analyses were performed on sediment fractions \u003c125 \u00b5m using an Elemental Analyzer-Isotope Ratio Mass Spectrometry (EA-IRMS) in the Stable Isotope Ecology Lab at LSU. Biological counts of feathers and hairs were determined by enumeration using a dissecting microscope of sediment fractions \u003e1000 \u00b5m. The data set also includes sediment core excavation site names and coordinates, date of excavation, sediment depth and age, and carbon to nitrogen isotopic ratios. Details of the data set and all relevant methods are provided in Kristan et al., 2021.", "east": -35.95, "geometry": ["POINT(-36.64 -54.335)"], "keywords": "Antarctica; Antarctic Fur Seal; Elemental Concentrations; King Penguin; Population Dynamics; South Atlantic Ocean; South Georgia Island; Stable Isotope Analysis; Sub-Antarctic", "locations": "Sub-Antarctic; South Georgia Island; South Atlantic Ocean; Antarctica", "north": -54.05, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Kristan, Allyson; Maiti, Kanchan; McMahon, Kelton; Polito, Michael", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -54.62, "title": "Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.", "uid": "601509", "west": -37.33}, {"awards": "1143836 Leventer, Amy", "bounds_geometry": ["POLYGON((120 -66,120.1 -66,120.2 -66,120.3 -66,120.4 -66,120.5 -66,120.6 -66,120.7 -66,120.8 -66,120.9 -66,121 -66,121 -66.1,121 -66.2,121 -66.3,121 -66.4,121 -66.5,121 -66.6,121 -66.7,121 -66.8,121 -66.9,121 -67,120.9 -67,120.8 -67,120.7 -67,120.6 -67,120.5 -67,120.4 -67,120.3 -67,120.2 -67,120.1 -67,120 -67,120 -66.9,120 -66.8,120 -66.7,120 -66.6,120 -66.5,120 -66.4,120 -66.3,120 -66.2,120 -66.1,120 -66))"], "date_created": "Tue, 27 Apr 2021 00:00:00 GMT", "description": "This dataset includes diatom data, both absolute abundance and relative contribution, for NBP1402 JPC43. ", "east": 121.0, "geometry": ["POINT(120.5 -66.5)"], "keywords": "Antarctica; Diatom; Holocene; Jumbo Piston Corer; NBP1402; R/v Nathaniel B. Palmer; Sabrina Coast; Sediment Core Data; Species Abundance; Totten Glacier", "locations": "Antarctica; Sabrina Coast; Totten Glacier", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy", "project_titles": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics", "projects": [{"proj_uid": "p0000008", "repository": "USAP-DC", "title": "Collaborative Research: Totten Glacier System and the Marine Record of Cryosphere - Ocean Dynamics"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "NBP1402 JPC43 Diatom Data", "uid": "601440", "west": 120.0}, {"awards": "1043092 Steig, Eric", "bounds_geometry": ["POLYGON((-158.72 -77.79,-154.056 -77.79,-149.392 -77.79,-144.728 -77.79,-140.064 -77.79,-135.4 -77.79,-130.736 -77.79,-126.072 -77.79,-121.408 -77.79,-116.744 -77.79,-112.08 -77.79,-112.08 -78.178,-112.08 -78.566,-112.08 -78.954,-112.08 -79.342,-112.08 -79.73,-112.08 -80.118,-112.08 -80.506,-112.08 -80.894,-112.08 -81.282,-112.08 -81.67,-116.744 -81.67,-121.408 -81.67,-126.072 -81.67,-130.736 -81.67,-135.4 -81.67,-140.064 -81.67,-144.728 -81.67,-149.392 -81.67,-154.056 -81.67,-158.72 -81.67,-158.72 -81.282,-158.72 -80.894,-158.72 -80.506,-158.72 -80.118,-158.72 -79.73,-158.72 -79.342,-158.72 -78.954,-158.72 -78.566,-158.72 -78.178,-158.72 -77.79))"], "date_created": "Tue, 22 Dec 2020 00:00:00 GMT", "description": "This data set contains the VSMOW-SLAP d17O, d18O, and 17O-excess data from the WAIS Divide Ice Core Project, Siple Dome and Taylor Dome, along with the published and VSMOW-SLAP normalized d17O, d18O, and 17O-excess for Vostok [Landais et al. 2008], EPICA Dome C and Talos Dome [Winkler et al., 2012]. The data cover the Last Glacial Maximum (25-20 ka), through the Early Holocene (12-9 ka) and into present-day (past 2 kyr)", "east": -112.08, "geometry": ["POINT(-135.4 -79.73)"], "keywords": "Antarctica; Ice Core; Oxygen Isotope; WAIS Divide", "locations": "Antarctica; WAIS Divide", "north": -77.79, "nsf_funding_programs": null, "persons": "Steig, Eric J.; Schoenemann, Spruce", "project_titles": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core", "projects": [{"proj_uid": "p0000010", "repository": "USAP-DC", "title": "Collaborative Research: Stable Isotopes of Ice in the Transition and Glacial Sections of the WAIS Divide Deep Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -81.67, "title": "17O excess from WAIS Divide, 0 to 25 ka BP", "uid": "601413", "west": -158.72}, {"awards": "0941678 ; 0424589 Gogineni, S. Prasad; 0733025 Blankenship, Donald; 1443690 Young, Duncan", "bounds_geometry": ["POLYGON((114 -74,115.2 -74,116.4 -74,117.6 -74,118.8 -74,120 -74,121.2 -74,122.4 -74,123.6 -74,124.8 -74,126 -74,126 -74.3,126 -74.6,126 -74.9,126 -75.2,126 -75.5,126 -75.8,126 -76.1,126 -76.4,126 -76.7,126 -77,124.8 -77,123.6 -77,122.4 -77,121.2 -77,120 -77,118.8 -77,117.6 -77,116.4 -77,115.2 -77,114 -77,114 -76.7,114 -76.4,114 -76.1,114 -75.8,114 -75.5,114 -75.2,114 -74.9,114 -74.6,114 -74.3,114 -74))"], "date_created": "Fri, 18 Dec 2020 00:00:00 GMT", "description": "The data set published here consists of 26 ice-penetrating radar IRHs (internal reflecting horizons) which were traced across multiple ice-penetrating radar surveys that deployed several generations of modern ice-penetrating radar sounders over a decade, between 2008 and 2018, over the Dome C region of the East Antarctic Plateau. The data set is associated to publication: Cavitte, M. G. P, Young, D. A, Mulvaney, R., Ritz, C., Greenbaum, J. S., Ng, G., Kempf, S. D., Quartini, E., Muldoon, G. R., Paden, J., Frezzotti, M., Roberts, J. L. , Tozer, C. R. , Schroeder, D. M. and Blankenship, D. D. A detailed radiostratigraphic data set for the central East Antarctic Plateau spanning from the Holocene to the mid-Pleistocene, Earth Syst. Sci. Data, 13, 4759\u20134777, 2021, https://doi.org/10.5194/essd-13-4759-2021.\r\n\r\nWe can subdivide the radar sounders used into three sets. The primary set was collected by the University of Texas at Austin Institute for Geophysics (UTIG) and the Australian Antarctic Division (AAD) as part of the ICECAP project) between 2008 and 2015. This includes the Oldest Ice candidate A (OIA) survey flown by ICECAP in January 2016. Data were collected with the High Capacity Airborne Radar Sounder (HiCARS) 1 \u0026 2 and its Multifrequency Airborne Radar-sounder for Full-phase Assessment (MARFA) descendant. The data was collected from a DC-3T Basler which operated from Concordia Station. \r\n\r\nThe second set consists of the Vostok-Dome C airborne radar transect was flown by the Center for Remote Sensing of Ice Sheets (CReSIS) at the University of Kansas using the Multi-Channel Coherent Radar Depth Sounder (MCoRDS) in a single flight line in 2013. A P-3 Orion operating from McMurdo Station collected these data as part of NASA Operation Ice Bridge. \r\n\r\nThe third set consists of a subset of the LDC ground-based radar survey, towed behind a PistenBully PB300 tractor, collected by the Beyond EPICA - Oldest Ice (BE-OI) European Consortium using the British Antarctic Survey\u2019s (BAS) Deep Looking Radio Echo Sounder (DELORES) radar system. Each IRH has been traced in all three radar sets and is published here as a single csv and netcdf file. Formats are self-documented in these csv/netcdf files. \r\n\r\nWhere HiCARS and MCoRDS radar transects are used, the IRH is provided at a 1 km spatial resolution, where DELORES radar transects are used, the IRH is provided at a 250 m spatial resolution. \r\n\r\nThe 26 IRHs published here were traced semi-automatically by first author Marie Cavitte, using Landmark\u0027s Decision Space Desktop software and its built-in picker. \r\n\r\nThe IRHs are dated at the EDC ice core using the AICC2012 timescale (Veres et al., 2013; Bazin et al., 2013). \r\n\r\nIce core ages are transferred onto the IRHs on radar transect MCM/JKB1a/EDMC01a at distance_m (column in the data sets) = 110.153 m along the transect. That radar point of closest approach is 94\u2009m away from the ice core site. Depth and age uncertainties associated to each IRH are quantified n the associated publication: Cavitte, M. G. P, Young, D. A, Mulvaney, R., Ritz, C., Greenbaum, J. S., Ng, G., Kempf, S. D., Quartini, E., Muldoon, G. R., Paden, J., Frezzotti, M., Roberts, J. L. , Tozer, C. R. , Schroeder, D. M. and Blankenship, D. D. A detailed radiostratigraphic data set for the central East Antarctic Plateau spanning from the Holocene to the mid-Pleistocene, Earth Syst. Sci. Data, 13, 4759\u20134777, 2021, https://doi.org/10.5194/essd-13-4759-2021. \r\n\n\r\n\r\nBesides NSF this dataset is the result of additional support from NERC grant - NE/D003733/1, NASA grants - NX08AN68G, NNX09AR52G, NNX11AD33G, NNX13AD53A, and funding from the G. Unger Vetlesen Foundation.\n\n\\nNote that the dataset was archived before the accompanying paper was officially published. The abstract and dataset description has been updated to cite the correct reference to the ESSD paper (Cavitte et al., 2021) after the paper was published. The headers of the actual data files contain only a placeholder to this reference.", "east": 126.0, "geometry": ["POINT(120 -75.5)"], "keywords": "Antarctica; East Antarctic Plateau; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; ICECAP; Ice Penetrating Radar; Internal Reflecting Horizons", "locations": "Antarctica; East Antarctic Plateau", "north": -74.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences", "persons": "Cavitte, Marie G. P; Young, Duncan A.; Mulvaney, Robert; Ritz, Catherine; Greenbaum, Jamin; Ng, Gregory; Kempf, Scott D.; Quartini, Enrica; Muldoon, Gail R.; Paden, John; Frezzotti, Massimo; Roberts, Jason; Tozer, Carly; Schroeder, Dustin; Blankenship, Donald D.", "project_titles": "Center for Remote Sensing of Ice Sheets (CReSIS); Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP); IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP)", "projects": [{"proj_uid": "p0000719", "repository": "USAP-DC", "title": "IPY Research: Investigating the Cryospheric Evolution of the Central Antarctic Plate (ICECAP)"}, {"proj_uid": "p0000102", "repository": "USAP-DC", "title": "Center for Remote Sensing of Ice Sheets (CReSIS)"}, {"proj_uid": "p0010115", "repository": "USAP-DC", "title": "Collaborative Research: Southern Plateau Ice-sheet Characterization and Evolution of the Central Antarctic Plate (SPICECAP)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Dome C Ice Core", "south": -77.0, "title": "Ice-penetrating radar internal stratigraphy over Dome C and the wider East Antarctic Plateau", "uid": "601411", "west": 114.0}, {"awards": "0724929 Simms, Alexander", "bounds_geometry": ["POLYGON((-61.8 -61.3,-61.07 -61.3,-60.34 -61.3,-59.61 -61.3,-58.88 -61.3,-58.15 -61.3,-57.42 -61.3,-56.69 -61.3,-55.96 -61.3,-55.23 -61.3,-54.5 -61.3,-54.5 -61.55,-54.5 -61.8,-54.5 -62.05,-54.5 -62.3,-54.5 -62.55,-54.5 -62.8,-54.5 -63.05,-54.5 -63.3,-54.5 -63.55,-54.5 -63.8,-55.23 -63.8,-55.96 -63.8,-56.69 -63.8,-57.42 -63.8,-58.15 -63.8,-58.88 -63.8,-59.61 -63.8,-60.34 -63.8,-61.07 -63.8,-61.8 -63.8,-61.8 -63.55,-61.8 -63.3,-61.8 -63.05,-61.8 -62.8,-61.8 -62.55,-61.8 -62.3,-61.8 -62.05,-61.8 -61.8,-61.8 -61.55,-61.8 -61.3))"], "date_created": "Fri, 06 Nov 2020 00:00:00 GMT", "description": "", "east": -54.5, "geometry": ["POINT(-58.15 -62.55)"], "keywords": "Antarctica; Grain Size; Granulometry; Joinville Island; Livingston Island; LMG0412; Raised Beaches", "locations": "Joinville Island; Livingston Island; Antarctica", "north": -61.3, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Theilen, Brittany; Simms, Alexander", "project_titles": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches", "projects": [{"proj_uid": "p0010132", "repository": "USAP-DC", "title": "Collaborative Research: New Constraints on Post-Glacial Rebound and Holocene Environmental History along the Northern Antarctic Peninsula from Raised Beaches"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -63.8, "title": "Granulometry of Joinville and Livingston Island beaches", "uid": "601400", "west": -61.8}, {"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": "Roosevelt Island; Siple Dome; James Ross Island; Bruce Plateau; Law Dome; South Pole; WAIS Divide; Antarctica; Greenland Ice Cap", "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": "1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((-58.62 -62.257,-58.6199 -62.257,-58.6198 -62.257,-58.6197 -62.257,-58.6196 -62.257,-58.6195 -62.257,-58.6194 -62.257,-58.6193 -62.257,-58.6192 -62.257,-58.6191 -62.257,-58.619 -62.257,-58.619 -62.2571,-58.619 -62.2572,-58.619 -62.2573,-58.619 -62.2574,-58.619 -62.2575,-58.619 -62.2576,-58.619 -62.2577,-58.619 -62.2578,-58.619 -62.2579,-58.619 -62.258,-58.6191 -62.258,-58.6192 -62.258,-58.6193 -62.258,-58.6194 -62.258,-58.6195 -62.258,-58.6196 -62.258,-58.6197 -62.258,-58.6198 -62.258,-58.6199 -62.258,-58.62 -62.258,-58.62 -62.2579,-58.62 -62.2578,-58.62 -62.2577,-58.62 -62.2576,-58.62 -62.2575,-58.62 -62.2574,-58.62 -62.2573,-58.62 -62.2572,-58.62 -62.2571,-58.62 -62.257))"], "date_created": "Sun, 11 Oct 2020 00:00:00 GMT", "description": "Many types of animal tissues are increasingly being used for stable isotope analysis, with their application dependent on the time frame they reflect and their availability for collection. Here, we investigated the isotopic values (\u03b413C and \u03b415N) of four tissues (feather, skin, toenail, and bone) collected from fledgling-period chick carcasses of three species of pygoscelid penguins to compare the variability and accuracy of the data among tissues. Samples were collected at 25 de Mayo/King George Island during the 2017/18 austral summer. Chick carcasses are commonly found at active penguin colonies, and \u201copportunistic sampling\u201d can easily be performed without disturbing nesting penguins. A total of 25\u201336 carcasses per species were sampled at active colonies of Ad\u00e9lie Pygoscelis adeliae, Gentoo P. papua, and Chinstrap P. antarcticus penguins. A linear mixed model showed that \u03b413C values varied significantly between tissues, presumably due to tissue-specific isotopic discrimination. In contrast, the only tissue with significantly different \u03b415N values was toenail. Stable isotope data revealed dietary differences among species, with Gentoo Penguins having higher average isotopic values in tissues compared to Ad\u00e9lie and Chinstrap penguins. In addition, Chinstrap Penguins showed a consistent, but not statistically significant, trend in having higher \u03b413C values compared to Ad\u00e9lie Penguins. Gentoo Penguins displayed the highest isotopic variability of any species for all tissues. Isotopic composition was most variable in skin in all three species making skin the least reliable tissue for isotope analysis, whereas isotopic values were least variable in toenails. Comparison of isotopic values between two bones (tibiotarsus and coracoid) showed no significant differences in isotopic values, indicating that when the same bone is not available for sampling from carcasses, sampling of any major skeletal element is likely to provide a meaningful comparison. These results allow for more informed opportunistic sampling to accurately estimate and compare penguin diet among species and between ancient and active colonies.", "east": -58.619, "geometry": ["POINT(-58.6195 -62.2575)"], "keywords": "25 De Mayo/King George Island; Antarctica; Biota; Delta 13C; Delta 15N; Dietary Shifts; Opportunistic Sampling; Penguin; Pygoscelis Penguins; Stranger Point", "locations": "Stranger Point; Antarctica; 25 De Mayo/King George Island", "north": -62.257, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Ciriani, Yanina; Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -62.258, "title": "Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica", "uid": "601382", "west": -58.62}, {"awards": "1443386 Emslie, Steven", "bounds_geometry": ["POINT(162.95 -75.55)"], "date_created": "Thu, 24 Sep 2020 00:00:00 GMT", "description": "This dataset provides the results of radiocarbon and stable isotope analyses of Adelie penguin chick bone collagen.", "east": 162.95, "geometry": ["POINT(162.95 -75.55)"], "keywords": "Adelie Penguin; Antarctica; Cape Irizar; Drygalski Ice Tongue; Ross Sea; Stable Isotopes", "locations": "Antarctica; Ross Sea; Cape Irizar; Drygalski Ice Tongue", "north": -75.55, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.55, "title": "Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica", "uid": "601374", "west": 162.95}, {"awards": "1826712 McMahon, Kelton; 1443585 Polito, Michael; 1443386 Emslie, Steven; 1443424 McMahon, Kelton", "bounds_geometry": ["POINT(-54.67855 -63.434067)"], "date_created": "Fri, 24 Jul 2020 00:00:00 GMT", "description": "This data set focuses on ornithogenic soils excavated from a test pit located in an active colony of Pygoscelis spp. penguins on Platter Island in the Danger Islands archipelago along the northeastern side of the Antarctic Peninsula in December 2015. It contains radiocarbon dates of recovered penguin tissues and the estimated age of ornithogenic soils by depth. It also contains measurements of carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values of Pygoscelis spp. penguins eggshell membrane and feather samples and Antarctic fur seal (Arctocephalus gazella) hair sample recovered from these ornithogenic soils. Accelerator Mass Spectrometry (AMS) was used to obtain radiocarbon dates at the Woods Hole National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. Radiocarbon Dates were corrected for the marine carbon reservoir effect and calibrated to calendar years before present (cal years BP) using a \u0394R of 750\u2009\u00b1\u200950 years and the MARINE13 calibration curve in Calib 7.04. The rbacon package ver. 2.3.9.1 in R was used to estimate age at depth of each soil level expressed as years relative to the common era (CE). Stable isotope analyses were conducted using an elemental analyzer coupled to a continuous flow stable isotope ratio mass spectrometer at Louisiana State University. The data set also includes associated data such as excavation date, location, site names, latitude/longitude, species, date of excavation, tissue used for radiocarbon dating, and carbon to nitrogen ratios. Details of the data set and all relevant methods are provided in Kalvakaalva et. al., 2020.", "east": -54.67855, "geometry": ["POINT(-54.67855 -63.434067)"], "keywords": "Antarctica; Antarctic Peninsula; Arctocephalus Gazella; Carbon; Holocene; Nitrogen; Paleoecology; Penguin; Pygoscelis Spp.; Stable Isotope Analysis; Weddell Sea", "locations": "Weddell Sea; Antarctica; Antarctic Peninsula", "north": -63.434067, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Kalvakaalva, Rohit; Clucas, Gemma; Herman, Rachael; Polito, Michael", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -63.434067, "title": "Radiocarbon dating and stable isotope values of penguin and seal tissues recovered from ornithogenic soils on Platter Island, Danger Islands Archipelago, Antarctic Peninsula in December 2015.", "uid": "601364", "west": -54.67855}, {"awards": "1643722 Brook, Edward J.", "bounds_geometry": ["POINT(180 -90)"], "date_created": "Wed, 03 Jun 2020 00:00:00 GMT", "description": "This data set contains measurements of atmospheric methane in the South Pole Ice core made at both Oregon State University and Penn State University, as well as a gas age time scale for the core. In both laboratories methane was measured using a melt-refreeze technique to liberate extracted air and using a gas chromatograph with flame ionization detection to quantify the methane concentration, by comparison to calibrated air standards. To construct the gas time scale abrupt changes in atmospheric methane during the glacial period and centennial methane variability during the Holocene were used to synchronize the South Pole gas record with analogous data from the West Antarctic Ice Sheet Divide ice core. Stratigraphic matching based on visual optimization was verified using an automated matching algorithm. The South Pole ice core recovers all expected changes in methane based on previous records. In combination with an existing ice age scale (Winski et al., 2019, Clim. Past, 15, 1793\u20131808) an independent estimate of the gas age-ice age difference is also provided. A full description of the data and gas age scale are provided in Epifanio et al., 2020 (Climate of the Past, 16, 2431-2444). ", "east": 180.0, "geometry": ["POINT(180 -90)"], "keywords": "Antarctica; Gas Chromatography; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; South Pole", "locations": "Antarctica; South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "A High Resolution Atmospheric Methane Record from the South Pole Ice Core", "projects": [{"proj_uid": "p0010102", "repository": "USAP-DC", "title": "A High Resolution Atmospheric Methane Record from the South Pole Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "South Pole Ice Core Methane Data and Gas Age Time Scale", "uid": "601329", "west": 180.0}, {"awards": "1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -60,-180 -61.130769444,-180 -62.261538888,-180 -63.392308332,-180 -64.523077776,-180 -65.65384722,-180 -66.784616664,-180 -67.915386108,-180 -69.046155552,-180 -70.176924996,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,-180 -71.30769444,180 -71.30769444,179.019305556 -71.30769444,178.038611112 -71.30769444,177.057916668 -71.30769444,176.077222224 -71.30769444,175.09652778 -71.30769444,174.115833336 -71.30769444,173.135138892 -71.30769444,172.154444448 -71.30769444,171.173750004 -71.30769444,170.19305556 -71.30769444,170.19305556 -70.176924996,170.19305556 -69.046155552,170.19305556 -67.915386108,170.19305556 -66.784616664,170.19305556 -65.65384722,170.19305556 -64.523077776,170.19305556 -63.392308332,170.19305556 -62.261538888,170.19305556 -61.130769444,170.19305556 -60,171.173750004 -60,172.154444448 -60,173.135138892 -60,174.115833336 -60,175.09652778 -60,176.077222224 -60,177.057916668 -60,178.038611112 -60,179.019305556 -60,-180 -60))"], "date_created": "Tue, 02 Jun 2020 00:00:00 GMT", "description": "We report new discoveries and radiocarbon dates on active and abandoned Ad\u00e9lie penguin (Pygoscelis adeliae) colonies at Cape Adare, Antarctica. This colony, first established at approximately 2000 BP (calendar years before present, i.e. 1950), is currently the largest for this species with approximately 338 000 breeding pairs, most located on lowlying Ridley Beach. We hypothesize that this colony first formed after fast ice began blocking open-water access by breeding penguins to the Scott Coast in the southern Ross Sea during a cooling period also at approximately 2000 BP. Our results suggest that the new colony at Cape Adare continued to grow, expanding to a large upper terrace above Ridley Beach, until it exceeded approximately 500 000 breeding pairs (a \u0027supercolony\u0027) by approximately 1200 BP. The high marine productivity associated with the Ross Sea polynya and continental shelf break supported this growth, but the colony collapsed to its present size for unknown reasons after approximately 1200 BP. Ridley Beach will probably be abandoned in the near future due to rising sea level in this region. We predict that penguins will retreat to higher elevations at Cape Adare and that the Scott Coast will be reoccupied by breeding penguins as fast ice continues to dissipate earlier each summer, restoring open-water access to beaches there.", "east": 170.19305556, "geometry": ["POINT(175.09652778 -65.65384722)"], "keywords": "Adelie Penguin; Antarctica; Biota; Cape Adare; East Antarctica; Population Movement; Pygoscelis Adeliae; Radiocarbon; Ross Sea; Sea Level Rise; Stable Isotopes", "locations": "Cape Adare; Antarctica; Ross Sea; East Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "McKenzie, Ashley; Patterson, William; Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -71.30769444, "title": "The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "uid": "601327", "west": -180.0}, {"awards": "1807522 Jones, Tyler", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Tue, 26 May 2020 00:00:00 GMT", "description": "The original water stable isotope data for the WAIS Divide Deep Ice Core was generated under the University of Colorado INSTAAR Stable Isotope Lab (NSF Award# 1443328). This data set contains high-resolution dD and d18O data for the West Antarctic Ice Sheet (WAIS) Divide Ice core. Drilling was initiated in 2006 and completed in 2011, and subsequent analyses on the ice were performed at the University of Colorado INSTAAR Stable Isotope Lab using Continuous Flow Analysis (CFA). The targeted resampling of the WAIS Divide Ice core (1035.4 - 1368.2m) occurred for this grant (NSF OPP - Antarctic Glaciology 1807522) to replace data analyzed on an older generation Laser Absorption Spectroscopy instrument. The resampling interval was identified using information theory.", "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Delta 18O; Delta Deuterium; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Snow/ice; Snow/Ice; WAIS Divide Ice Core; Water Isotopes; West Antarctic Ice Sheet", "locations": "Antarctica; West Antarctic Ice Sheet", "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Morris, Valerie; Jones, Tyler R.; Vaughn, Bruce; White, James", "project_titles": "Collaborative Research: Targeted resampling of deep polar ice cores using information theory", "projects": [{"proj_uid": "p0010100", "repository": "USAP-DC", "title": "Collaborative Research: Targeted resampling of deep polar ice cores using information theory"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Mid-Holocene high-resolution water isotope time series for the WAIS Divide ice core", "uid": "601326", "west": -112.1115}, {"awards": "1826712 McMahon, Kelton; 1443585 Polito, Michael; 1443424 McMahon, Kelton; 1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((162 -72,162.9 -72,163.8 -72,164.7 -72,165.6 -72,166.5 -72,167.4 -72,168.3 -72,169.2 -72,170.1 -72,171 -72,171 -72.6,171 -73.2,171 -73.8,171 -74.4,171 -75,171 -75.6,171 -76.2,171 -76.8,171 -77.4,171 -78,170.1 -78,169.2 -78,168.3 -78,167.4 -78,166.5 -78,165.6 -78,164.7 -78,163.8 -78,162.9 -78,162 -78,162 -77.4,162 -76.8,162 -76.2,162 -75.6,162 -75,162 -74.4,162 -73.8,162 -73.2,162 -72.6,162 -72))"], "date_created": "Tue, 03 Mar 2020 00:00:00 GMT", "description": "This data set contains measurements of carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values of feather, skin, bone, and toenail samples of mummified Ad\u00e9lie penguin chick remains excavated from multiple sites around the Ross Sea region of Antarctica between 2004 and 2016, as well as the same measurements for modern Ad\u00e9lie chicks collected from the surface of Cape Hallett and Adelie Cove in January 2016. Stable isotope analyses were conducted using an elemental analyzer coupled to a continuous flow stable isotope ratio mass spectrometer. Where possible, accelerator Mass Spectrometry (AMS) radiocarbon dates on selected mummy tissues were completed at the Rafter Radiocarbon Laboratory, New Zealand (NZA), Beta Analytic, Inc. (Beta), the University of Georgia Center for Applied Isotope Studies (UGAMS), and Woods Hole National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. All dates were corrected for the marine carbon reservoir effect and calibrated to calendar years before present (cal years BP) using a \u0394R of 750\u2009\u00b1\u200950 years and the MARINE13 calibration curve in Calib 7.0 (2\u03c3 range). \r\nThe data set also includes excavation/collection site names and latitude/longitude, date of excavation/collection, tissue used for radiocarbon dating, and carbon to nitrogen ratios. Details of the data set and all relevant methods are provided in Kristan et. al., 2019.\r\n", "east": 171.0, "geometry": ["POINT(166.5 -75)"], "keywords": "Abandoned Colonies; Antarctica; Holocene; Penguin; Ross Sea; Stable Isotope Analysis", "locations": "Antarctica; Ross Sea; Antarctica", "north": -72.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Kristan, Allyson; Patterson, William; Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Radioisotope dates and carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values from modern and mummified Ad\u00e9lie Penguin chick carcasses and tissue from the Ross Sea, Antarctica", "uid": "601263", "west": 162.0}, {"awards": "1443585 Polito, Michael; 1826712 McMahon, Kelton; 1443424 McMahon, Kelton; 1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((-63.56 -60.72,-61.664 -60.72,-59.768 -60.72,-57.872 -60.72,-55.976 -60.72,-54.08 -60.72,-52.184 -60.72,-50.288 -60.72,-48.392 -60.72,-46.496 -60.72,-44.6 -60.72,-44.6 -61.106,-44.6 -61.492,-44.6 -61.878,-44.6 -62.264,-44.6 -62.65,-44.6 -63.036,-44.6 -63.422,-44.6 -63.808,-44.6 -64.194,-44.6 -64.58,-46.496 -64.58,-48.392 -64.58,-50.288 -64.58,-52.184 -64.58,-54.08 -64.58,-55.976 -64.58,-57.872 -64.58,-59.768 -64.58,-61.664 -64.58,-63.56 -64.58,-63.56 -64.194,-63.56 -63.808,-63.56 -63.422,-63.56 -63.036,-63.56 -62.65,-63.56 -62.264,-63.56 -61.878,-63.56 -61.492,-63.56 -61.106,-63.56 -60.72))"], "date_created": "Tue, 17 Dec 2019 00:00:00 GMT", "description": "This data set contains measurements of nitrogen (\u03b415N) stable isotope values of twelve individual amino acids from breast feathers of gentoo penguins (Pygoscelis papua) and chinstrap penguins (Pygoscelis antarctica) collected from museum archives between the 1930s and 2010s. Stable isotope analyses were conducted using a gas chromatograph coupled to a continuous flow stable isotope ratio mass spectrometer. The data set also includes trophic positions of penguins calculated from individual amino acid \u03b415N values.\r\nThe data set indexes each individual penguin with species, collection institution, catalog number, sex, locality, latitude, longitude, year of sample collection, nitrogen isotope ratios, and calculated trophic position. Details of the data set and all relevant methods are provided in McMahon et al. 2020 Proc Natl Acad Sci DOI: 10.1073/pnas.1913093116 ", "east": -44.6, "geometry": ["POINT(-54.08 -62.65)"], "keywords": "Amino Acids; Antarctica; Antarctic Peninsula; Biota; Isotope Data; Nitrogen Isotopes; Oceans; Penguin; Southern Ocean; Stable Isotope Analysis", "locations": "Antarctica; Antarctic Peninsula; Southern Ocean; Antarctica", "north": -60.72, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "McMahon, Kelton; Polito, Michael", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.58, "title": "Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s", "uid": "601232", "west": -63.56}, {"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": "Liv Glacier; Transantarctic Mountains; 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": "1826712 McMahon, Kelton; 1443386 Emslie, Steven; 1443585 Polito, Michael; 1443424 McMahon, Kelton", "bounds_geometry": ["POLYGON((-59 -62,-58.9 -62,-58.8 -62,-58.7 -62,-58.6 -62,-58.5 -62,-58.4 -62,-58.3 -62,-58.2 -62,-58.1 -62,-58 -62,-58 -62.1,-58 -62.2,-58 -62.3,-58 -62.4,-58 -62.5,-58 -62.6,-58 -62.7,-58 -62.8,-58 -62.9,-58 -63,-58.1 -63,-58.2 -63,-58.3 -63,-58.4 -63,-58.5 -63,-58.6 -63,-58.7 -63,-58.8 -63,-58.9 -63,-59 -63,-59 -62.9,-59 -62.8,-59 -62.7,-59 -62.6,-59 -62.5,-59 -62.4,-59 -62.3,-59 -62.2,-59 -62.1,-59 -62))"], "date_created": "Tue, 24 Sep 2019 00:00:00 GMT", "description": "Radiocarbon dates from pygoscelid penguin tissues from ornithogenic soils and beach deposits at Stranger Point, King George (25 de Mayo) Island, Antarctic Peninsula. Uncorrected dates are in radiocarbon years before present (BP); calibrated dates were corrected for the marine carbon reservoir effect (delta R = 700 +/- 50 years) and calibrated with Calib 7.0.4 to provide 2\u03c3 ranges in calendar years BP. All dates except were completed at the Woods Hole National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility and are designated with OS numbers. Localities include ancient penguin breedings sites (mounds, M), active colonies (I9, B3), and a mid-Holocene marine beach deposit (Pingfo 1).", "east": -58.0, "geometry": ["POINT(-58.5 -62.5)"], "keywords": "Abandoned Colonies; Antarctica; Antarctic Peninsula; Beach Deposit; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Holocene; Penguin; Radiocarbon; Radiocarbon Dates; Snow/ice; Snow/Ice; Stranger Point", "locations": "Stranger Point; Antarctic Peninsula; Antarctica", "north": -62.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Emslie, Steven D.", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -63.0, "title": "Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula", "uid": "601212", "west": -59.0}, {"awards": "1443585 Polito, Michael; 1826712 McMahon, Kelton; 1443424 McMahon, Kelton; 1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((-63 -60,-62.1 -60,-61.2 -60,-60.3 -60,-59.4 -60,-58.5 -60,-57.6 -60,-56.7 -60,-55.8 -60,-54.9 -60,-54 -60,-54 -60.4,-54 -60.8,-54 -61.2,-54 -61.6,-54 -62,-54 -62.4,-54 -62.8,-54 -63.2,-54 -63.6,-54 -64,-54.9 -64,-55.8 -64,-56.7 -64,-57.6 -64,-58.5 -64,-59.4 -64,-60.3 -64,-61.2 -64,-62.1 -64,-63 -64,-63 -63.6,-63 -63.2,-63 -62.8,-63 -62.4,-63 -62,-63 -61.6,-63 -61.2,-63 -60.8,-63 -60.4,-63 -60))"], "date_created": "Fri, 13 Sep 2019 00:00:00 GMT", "description": "This data set contains measurements of carbon (\u03b413C) and nitrogen (\u03b415N) stable isotope values of whole-body Antarctic krill (Euphausia superba) collected from trawl surveys of waters surrounding the South Shetland Islands and the northern Antarctic Peninsula during the 2006-07 and 2008-90 Austral summers. Stable isotope analyses were conducted using an elemental analyzer coupled to a continuous flow stable isotope ratio mass spectrometer. Individual krill were lipid-extracted prior to analyses. The data set also includes latitude, longitude, month, and year of sample collection, standard length of the krill to the nearest mm, age class, sex, and carbon to nitrogen ratios. Details of the data set and all relevant methods are provided in Polito et al., 2013 and Polito et al., 2019.", "east": -54.0, "geometry": ["POINT(-58.5 -62)"], "keywords": "Antarctica; Antarctic Krill; Antarctic Peninsula; Biota; Carbon Isotopes; Isotope Data; Krill; Nitrogen Isotopes; Oceans; Southern Ocean; Stable Isotope Analysis", "locations": "Antarctic Peninsula; Southern Ocean; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Polito, Michael", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009", "uid": "601210", "west": -63.0}, {"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": "Transantarctic Mountains; Ross Embayment; Ross Sea; 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": "1443336 Osterberg, Erich", "bounds_geometry": ["POINT(-180 -90)"], "date_created": "Thu, 29 Aug 2019 00:00:00 GMT", "description": "The South Pole Ice Core (SPICEcore) was drilled in 2014-2016 to provide a detailed multi-proxy archive of paleoclimate conditions in East Antarctica during the Holocene and late Pleistocene. Interpretation of these records requires an accurate depth-age relationship. Here, we present the SP19 timescale for the age of the ice of SPICEcore. SP19 is synchronized to the WD2014 chronology from the West Antarctic Ice Sheet Divide (WAIS Divide) ice core using stratigraphic matching of 251 volcanic events. These events indicate an age of 54,302 +/- 519 years BP (before the year 1950) at the bottom of SPICEcore. Annual layers identified in sodium and magnesium ions to 11,341 BP were used to interpolate between stratigraphic volcanic tie points, yielding an annually-resolved chronology through the Holocene. Estimated timescale uncertainty during the Holocene is less than 18 years relative to WD2014, with the exception of the interval between 1800 to 3100 BP when uncertainty estimates reach +/- 25 years due to widely spaced volcanic tie points. Prior to the Holocene, uncertainties remain within 124 years relative to WD2014. Results show an average Holocene accumulation rate of 7.4 cm/yr (water equivalent). The time variability of accumulation rate is consistent with expectations for steady-state ice flow through the modern spatial pattern of accumulation rate. Time variations in nitrate concentration, nitrate seasonal amplitude, and \u03b415N of N2 in turn are as expected for the accumulation-rate variations. The highly variable yet well-constrained Holocene accumulation history at the site can help improve scientific understanding of deposition-sensitive climate proxies such as \u03b415N of N2 and photolyzed chemical compounds.", "east": -180.0, "geometry": ["POINT(-180 -90)"], "keywords": "Antarctica; Calcium (ca); Chemistry:ice; Chemistry:Ice; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciochemistry; Glaciology; Ice; Ice Core; Ice Core Chemistry; Ice Core Data; Ice Core Records; Ice Core Stratigraphy; Nitrate; Nitrogen Isotopes; Paleoclimate; Snow/ice; Snow/Ice; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Winski, Dominic A.; Fudge, T. J.; Dunbar, Nelia; Buizert, Christo; Bay, Ryan; Souney, Joseph Jr.; Sigl, Michael; McConnell, Joseph; Fegyveresi, John; Cole-Dai, Jihong; Thundercloud, Zayta; Cox, Thomas S.; Kreutz, Karl; Epifanio, Jenna; Ortman, Nikolas; Brook, Edward J.; Beaudette, Ross; Sowers, Todd A.; Steig, Eric J.; Morris, Valerie; Kahle, Emma; Ferris, David G.; Aydin, Murat; Nicewonger, Melinda R.; Casey, Kimberly A.; Alley, Richard; Waddington, Edwin D.; Osterberg, Erich; Severinghaus, Jeffrey P.; Jones, Tyler R.; Iverson, Nels", "project_titles": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements", "projects": [{"proj_uid": "p0010051", "repository": "USAP-DC", "title": "Collaborative Research: South Pole Ice Core Chronology and Climate Records using Chemical and Microparticle Measurements"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "The South Pole Ice Core (SPICEcore) chronology and supporting data", "uid": "601206", "west": -180.0}, {"awards": "1443550 Brook, Edward J.", "bounds_geometry": ["POINT(-180 -90)"], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "Measurements of CO2, N2O, and the isotopic composition of CO2 from the Holocene section of SPICEcore", "east": -180.0, "geometry": ["POINT(-180 -90)"], "keywords": "Antarctica; Carbon Dioxide; Ice Core Gas Records; Nitrous Oxide; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "Controls on Variations in Atmospheric Carbon Dioxide and Nitrous Oxide During the Last 10,000 years", "projects": [{"proj_uid": "p0010043", "repository": "USAP-DC", "title": "Controls on Variations in Atmospheric Carbon Dioxide and Nitrous Oxide During the Last 10,000 years"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "SPICEcore Holocene CO2 and N2O data", "uid": "601197", "west": -180.0}, {"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": "9909367 Leventer, Amy", "bounds_geometry": ["POLYGON((57 -66,57.3 -66,57.6 -66,57.9 -66,58.2 -66,58.5 -66,58.8 -66,59.1 -66,59.4 -66,59.7 -66,60 -66,60 -66.1,60 -66.2,60 -66.3,60 -66.4,60 -66.5,60 -66.6,60 -66.7,60 -66.8,60 -66.9,60 -67,59.7 -67,59.4 -67,59.1 -67,58.8 -67,58.5 -67,58.2 -67,57.9 -67,57.6 -67,57.3 -67,57 -67,57 -66.9,57 -66.8,57 -66.7,57 -66.6,57 -66.5,57 -66.4,57 -66.3,57 -66.2,57 -66.1,57 -66))"], "date_created": "Thu, 25 Apr 2019 00:00:00 GMT", "description": "This data set describes diatom assemblages and abundances from two sediment cores retrieved from Edward VIII Gulf. The assemblages are used to reconstruct paleoceanographic conditions throughout the Holocene.", "east": 60.0, "geometry": ["POINT(58.5 -66.5)"], "keywords": "Antarctica; Biota; Diatom; East Antarctica; Microscopy; NBP0101; Oceans; Paleoceanography; Paleoclimate; R/v Nathaniel B. Palmer; Sediment Corer", "locations": "East Antarctica; Antarctica", "north": -66.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Leventer, Amy", "project_titles": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin", "projects": [{"proj_uid": "p0000609", "repository": "USAP-DC", "title": "Quaternary Glacial History and Paleoenvironments of the East Antarctic Margin"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Diatom assemblages from Edward VIII Gulf, Kemp Coast, East Antarctica", "uid": "601177", "west": 57.0}, {"awards": "0839075 Priscu, John", "bounds_geometry": ["POINT(-112 -79)"], "date_created": "Tue, 12 Dec 2017 00:00:00 GMT", "description": "This data set includes raw concentration of prokaryotic cells for the WAIS Divide deep core, WDC06A, from 1,764 m to 2,709 m. Data were collected by a method that combines acquisition of discrete samples using a continuous ice-core melting system (McConnell et al., 2002) coupled with flow cytometry of DNA-stained samples. The method is described in detail in Santibanez et al., 2016. \r\r\nWe present the first long-term, highly resolved prokaryotic cell concentration record obtained from a polar ice core. This record, obtained from the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core, spanned from the Last Glacial Maximum (LGM) to the early Holocene (EH) and showed distinct fluctuations in prokaryotic cell concentration coincident with major climatic states. This record provided strong evidence that airborne prokaryotic cell deposition differed during the LGM, LDG and EH, and that these changes in cell densities could be explained by different environmental conditions during each of these climatic periods. Our observations provide the first ice core time-series evidence for a prokaryotic response to long-term climatic and environmental processes.", "east": -112.0, "geometry": ["POINT(-112 -79)"], "keywords": "Antarctica; Biota; Cell Counts; Glaciology; Microbiology; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Santibanez, Pamela; Priscu, John", "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": -79.0, "title": "Prokaryotic cell concentration record from the WAIS Divide ice core", "uid": "601072", "west": -112.0}, {"awards": "1043518 Brook, Edward J.", "bounds_geometry": ["POLYGON((-113 -79,-112.8 -79,-112.6 -79,-112.4 -79,-112.2 -79,-112 -79,-111.8 -79,-111.6 -79,-111.4 -79,-111.2 -79,-111 -79,-111 -79.1,-111 -79.2,-111 -79.3,-111 -79.4,-111 -79.5,-111 -79.6,-111 -79.7,-111 -79.8,-111 -79.9,-111 -80,-111.2 -80,-111.4 -80,-111.6 -80,-111.8 -80,-112 -80,-112.2 -80,-112.4 -80,-112.6 -80,-112.8 -80,-113 -80,-113 -79.9,-113 -79.8,-113 -79.7,-113 -79.6,-113 -79.5,-113 -79.4,-113 -79.3,-113 -79.2,-113 -79.1,-113 -79))"], "date_created": "Mon, 11 Sep 2017 00:00:00 GMT", "description": "Below we present the early Holocene discrete CH4 dataset from Siple Dome (SDMA), Antarctica, measured at Oregon State University (OSU) and Seoul National University (SNU) by discrete wet extraction technique. Analytical method is described in Grachev et al. (2009) and Mitchell et al. (2011) for OSU data, and Yang et al. (2017) for SNU data. SDMA CH4 composite record was constructed by combining OSU data for 7.6 - 9.0 ka and SNU data for 9.0 - 11.6 ka to maximize temporal resolution. SDMA gas chronology was synchronized to Greenland Ice Core Chronology 2005 (GICC05) scale. For detailed description on synchronization and age uncertainty please refer to Yang et al. (2017).", "east": -111.0, "geometry": ["POINT(-112 -79.5)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; Siple Dome; Siple Dome Ice Core", "locations": "Siple Dome; Antarctica", "north": -79.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Yang, Ji-Woong; Ahn, Jinho", "project_titles": "Collaborative Research: Completing an ultra-high resolution methane record from the WAIS Divide ice core", "projects": [{"proj_uid": "p0000185", "repository": "USAP-DC", "title": "Collaborative Research: Completing an ultra-high resolution methane record from the WAIS Divide ice core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core; Siple Dome Ice Core", "south": -80.0, "title": "Early Holocene methane records from Siple Dome, Antarctica", "uid": "601055", "west": -113.0}, {"awards": "1246190 Yu, Zicheng", "bounds_geometry": ["POLYGON((-68.5 -64,-67.73 -64,-66.96 -64,-66.19 -64,-65.42 -64,-64.65 -64,-63.88 -64,-63.11 -64,-62.34 -64,-61.57 -64,-60.8 -64,-60.8 -64.36,-60.8 -64.72,-60.8 -65.08,-60.8 -65.44,-60.8 -65.8,-60.8 -66.16,-60.8 -66.52,-60.8 -66.88,-60.8 -67.24,-60.8 -67.6,-61.57 -67.6,-62.34 -67.6,-63.11 -67.6,-63.88 -67.6,-64.65 -67.6,-65.42 -67.6,-66.19 -67.6,-66.96 -67.6,-67.73 -67.6,-68.5 -67.6,-68.5 -67.24,-68.5 -66.88,-68.5 -66.52,-68.5 -66.16,-68.5 -65.8,-68.5 -65.44,-68.5 -65.08,-68.5 -64.72,-68.5 -64.36,-68.5 -64))"], "date_created": "Mon, 24 Jul 2017 00:00:00 GMT", "description": "We used subfossil mosses and peats to document changes in regional climate, cryosphere, and terrestrial ecosystems in the western Antarctic Peninsula at ~65S latitude. We find that most peat-forming ecosystems have initiated since 2800 cal BP, in response to warmer summers and increasing summer insolation. The period at 900-600 cal BP was coldest as indicated by ice advance, abundance of kill ages from ice-entombed mosses exposed recently from retreating glacial ice, and apparent gap in peatbank initiation. Furthermore, the discovery of a novel Antarctic hairgrass (Deschampsia antarctica) peatland at 2300-1200 cal BP from the mainland Antarctic Peninsula suggests a much warmer climate than the present. A warming and wetting climate in the 1980s caused very high carbon accumulation in a Polytrichum strictum moss peatbank. Our results document dramatic transformations of landscape and ecosystems in response to past warmer climate, providing a telltale sign for what may come in the future.", "east": -60.8, "geometry": ["POINT(-64.65 -65.8)"], "keywords": "Antarctica; Antarctic Peninsula; Biota; Moss; Paleoclimate; Sample/collection Description; Sample/Collection Description", "locations": "Antarctic Peninsula; Antarctica", "north": -64.0, "nsf_funding_programs": null, "persons": "Yu, Zicheng", "project_titles": "Collaborative Research: Response of Carbon Accumulation in Moss Peatbanks to Past Warm Climates in the Antarctic Peninsula", "projects": [{"proj_uid": "p0000341", "repository": "USAP-DC", "title": "Collaborative Research: Response of Carbon Accumulation in Moss Peatbanks to Past Warm Climates in the Antarctic Peninsula"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.6, "title": "Late Holocene paleoecological and paleoclimatic data from moss peatbanks in the western Antarctic Peninsula", "uid": "601037", "west": -68.5}, {"awards": "0839093 McConnell, Joseph", "bounds_geometry": ["POLYGON((161.41425 -77.73489,161.486884 -77.73489,161.559518 -77.73489,161.632152 -77.73489,161.704786 -77.73489,161.77742 -77.73489,161.850054 -77.73489,161.922688 -77.73489,161.995322 -77.73489,162.067956 -77.73489,162.14059 -77.73489,162.14059 -77.747868,162.14059 -77.760846,162.14059 -77.773824,162.14059 -77.786802,162.14059 -77.79978,162.14059 -77.812758,162.14059 -77.825736,162.14059 -77.838714,162.14059 -77.851692,162.14059 -77.86467,162.067956 -77.86467,161.995322 -77.86467,161.922688 -77.86467,161.850054 -77.86467,161.77742 -77.86467,161.704786 -77.86467,161.632152 -77.86467,161.559518 -77.86467,161.486884 -77.86467,161.41425 -77.86467,161.41425 -77.851692,161.41425 -77.838714,161.41425 -77.825736,161.41425 -77.812758,161.41425 -77.79978,161.41425 -77.786802,161.41425 -77.773824,161.41425 -77.760846,161.41425 -77.747868,161.41425 -77.73489))"], "date_created": "Mon, 19 Jun 2017 00:00:00 GMT", "description": "Black carbon (BC) and other biomass-burning (BB) aerosols are critical components of climate forcing but quantification, predictive climate modeling, and policy decisions have been hampered by limited understanding of the climate drivers of BB and by the lack of long-term records. Prior modeling studies suggested that increased Northern Hemisphere anthropogenic BC emissions increased recent temperatures and regional precipitation, including a northward shift in the Inter-Tropical Convergence Zone (ITCZ). Two Antarctic ice cores were analyzed for BC and the longest record shows that the highest BC deposition during the Holocene occurred ~8-6k years before present in a period of relatively high austral burning season and low growing season insolation. Atmospheric transport modeling suggests South America (SA) as the dominant source of modern Antarctic BC and, consistent with the ice-core record, climate model experiments using mid-Holocene and preindustrial insolation simulate comparable increases in carbon loss due to fires in SA during the mid-Holocene. SA climate proxies document a northward shifted ITCZ and weakened SA Summer Monsoon (SASM) during this period, with associated impacts on hydroclimate and burning. A second Antarctic ice core spanning the last 2.5k years documents similar linkages between hydroclimate and BC, with the lowest deposition during the Little Ice Age characterized by a southerly shifted ITCZ and strengthened SASM. These new results indicate that insolation-driven changes in SA hydroclimate and BB, likely linked to the position of the ITCZ, modulated Antarctic BC deposition during most of the Holocene and suggests connections and feedbacks between future BC emissions and hydroclimate.", "east": 162.14059, "geometry": ["POINT(161.77742 -77.79978)"], "keywords": "Antarctica; Atmosphere; Black Carbon; Chemistry:ice; Chemistry:Ice; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -77.73489, "nsf_funding_programs": null, "persons": "McConnell, Joseph; Arienzo, Monica", "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": -77.86467, "title": "Holocene Black Carbon in Antarctica", "uid": "601034", "west": 161.41425}, {"awards": "0944197 Waddington, Edwin", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Tue, 28 Mar 2017 00:00:00 GMT", "description": "The West Antarctic Ice Sheet Divide (WAIS Divide, WD) ice core is a newly drilled, high-accumulation deep ice core that provides Antarctic climate records of the past ~68 ka at unprecedented temporal resolution. The upper 2850 m (back to 31.2 ka BP) have been dated using annual-layer counting. Here we present a chronology for the deep part of the core (67.8-31.2 ka BP), which is based on stratigraphic matching to annual-layer-counted Greenland ice cores using globally well-mixed atmospheric methane. We calculate the WD gas age-ice age difference (Delta age) using a combination of firn densification modeling, ice-flow modeling, and a data set of d15N-N2, a proxy for past firn column thickness. The largest Delta age at WD occurs during the Last Glacial Maximum, and is 525 +/- 120 years. Internally consistent solutions can be found only when assuming little to no influence of impurity content on densification rates, contrary to a recently proposed hypothesis. We synchronize the WD chronology to a linearly scaled version of the layer-counted Greenland Ice Core Chronology (GICC05), which brings the age of Dansgaard-Oeschger (DO) events into agreement with the U/Th absolutely dated Hulu Cave speleothem record. The small Delta age at WD provides valuable opportunities to investigate the timing of atmospheric greenhouse gas variations relative to Antarctic climate, as well as the interhemispheric phasing of the \\\"bipolar seesaw\\\".\n\nWe present the WD2014 chronology for the upper part (0-2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposition of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cosmogenic isotope records of 10Be from WAIS Divide and 14C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5% of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1% of the age at three abrupt climate change events between 27 and 31ka. WD2014 has consistently younger ages than Greenland ice core chronologies during most of the Holocene. For the Younger Dryas-Preboreal transition (11.595 ka; 24 years younger) and the Bolling-Allerod Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity, atmospheric mineral dust, and atmospheric methane concentrations.", "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Depth-Age-Model; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.481, "nsf_funding_programs": null, "persons": "Fudge, T. J.", "project_titles": "Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core", "projects": [{"proj_uid": "p0000026", "repository": "USAP-DC", "title": "Collaborative Research: Establishing the Chronology and Histories of Accumulation and Ice Dynamics for the WAIS Divide Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "WD2014: Timescale for WAIS Divide Core 2006 A (WDC-06A)", "uid": "601015", "west": -112.1115}, {"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": "Antarctica; WAIS Divide", "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": "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": "Transantarctic Mountains; Antarctica; Taylor Glacier", "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": "0739575 Emslie, Steven", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "The research combines interdisciplinary study in geology, paleontology, and biology, using stable isotope and radiocarbon analyses, to examine how climate change and resource utilization have influenced population distribution, movement, and diet in penguins during the mid-to-late Holocene. Previous investigations have demonstrated that abandoned colonies contain well-preserved remains that can be used to examine differential responses of penguins to climate change in various sectors of Antarctica. As such, the research team will investigate abandoned and active pygoscelid penguin (Adelie, Chinstrap, and Gentoo) colonies in the Antarctic Peninsula and Ross Sea regions, and possibly Prydz Bay, in collaboration with Chinese scientists during four field seasons. Stable isotope analyses will be conducted on recovered penguin tissues and prey remains in guano to address hypotheses on penguin occupation history, population movement, and diet in relation to climate change since the late Pleistocene. The study will include one Ph.D., two Masters and 16 undergraduate students in advanced research over the project period. Students will be exposed to a variety of fields, the scientific method, and international scientific research. They will complete field and lab research for individual projects or Honor\u0027s theses for academic credit. The project also will include web-based outreach, lectures to middle school students, and the development of interactive exercises that highlight hypothesis-driven research and the ecology of Antarctica. Two undergraduate students in French and Spanish languages at UNCW will be hired to assist in translating the Web page postings for broader access to this information.\n", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Antarctic Peninsula; Biota; Geochronology; Global; Penguin; Ross Sea; Sample/collection Description; Sample/Collection Description; Scotia Sea; Southern Ocean", "locations": "Antarctic Peninsula; Antarctica; Scotia Sea; Ross Sea; Global; Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "Patterson, William; Polito, Michael; Emslie, Steven D.", "project_titles": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "projects": [{"proj_uid": "p0000317", "repository": "USAP-DC", "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Stable Isotope Analyses of Pygoscelid Penguin remains from Active and Abandoned Colonies in Antarctica", "uid": "600145", "west": -180.0}, {"awards": "0636953 Saltzman, Eric", "bounds_geometry": ["POINT(158.43 -77.48)"], "date_created": "Wed, 10 Sep 2014 00:00:00 GMT", "description": "This data set includes methyl chloride (CH\u003csub\u003e3\u003c/sub\u003eCI) measurements made on air extracted from 62 samples from the Taylor Dome M3C1 ice core in East Antarctica. CH\u003csub\u003e3\u003c/sub\u003eCI was measured in air from the Taylor Dome ice core to reconstruct an atmospheric record for the Holocene (11-0 kyr B.P.) and part of the last glacial period (50-30 kyr B.P.).", "east": 158.43, "geometry": ["POINT(158.43 -77.48)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "locations": "Taylor Dome; Antarctica", "north": -77.48, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Saltzman, Eric; Aydin, Murat", "project_titles": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores", "projects": [{"proj_uid": "p0000042", "repository": "USAP-DC", "title": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.48, "title": "Methyl Chloride Measurements in the Taylor Dome M3C1 Ice Core", "uid": "609600", "west": 158.43}, {"awards": "0636953 Saltzman, Eric", "bounds_geometry": ["POINT(157.4 -77.44)"], "date_created": "Wed, 10 Sep 2014 00:00:00 GMT", "description": "The data set includes methyl bromide (CH3Br) measurements made on air extracted from 70 samples from the Taylor Dome M3C1 ice core. CH3Br was measured in air from the Taylor Dome ice core to reconstruct an atmospheric record for the Holocene (11-0 kyr B.P.) and part of the last glacial period (50-30 kyr B.P.).", "east": 157.4, "geometry": ["POINT(157.4 -77.44)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "locations": "Antarctica; Taylor Dome", "north": -77.44, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Saltzman, Eric; Aydin, Murat", "project_titles": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores", "projects": [{"proj_uid": "p0000042", "repository": "USAP-DC", "title": "Methyl Chloride, Methyl Bromide, and Carbonyl Sulfide in Deep Antarctic Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.44, "title": "Methyl Bromide Measurements in the Taylor Dome M3C1 Ice Core", "uid": "609598", "west": 157.4}, {"awards": "0944764 Brook, Edward J.", "bounds_geometry": ["POINT(-148.82 -81.66)"], "date_created": "Wed, 25 Jun 2014 00:00:00 GMT", "description": "This data set provides a new CO2 record from the Siple Dome ice core, Antarctica, that covers 7.4-9.0 ka (thousand years) with 8- to 16-year resolution. A small, about 1-2 ppm, increase of atmospheric CO2 during the 8.2 ka event was observed. The increase is not significant when compared to other centennial variations in the Holocene that are not linked to large temperature changes. The results do not agree with leaf stomata records that suggest a CO2 decrease of up to ~25 ppm and imply that the sensitivity of atmospheric CO2 to the primarily northern hemisphere cooling of the 8.2 ka event was limited.", "east": -148.82, "geometry": ["POINT(-148.82 -81.66)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Geochronology; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; South Pole; WAISCORES", "locations": "Antarctica; South Pole; Siple Dome", "north": -81.66, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.; Ahn, Jinho", "project_titles": "Atmospheric CO2 and Abrupt Climate Change", "projects": [{"proj_uid": "p0000179", "repository": "USAP-DC", "title": "Atmospheric CO2 and Abrupt Climate Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.66, "title": "High-resolution Atmospheric CO2 during 7.4-9.0 ka", "uid": "609527", "west": -148.82}, {"awards": "0944584 Sowers, Todd; 0538578 Brook, Edward J.; 0538538 Sowers, Todd", "bounds_geometry": ["POINT(-38.5 72.6)", "POINT(-112.0865 -79.4676)"], "date_created": "Fri, 31 Jan 2014 00:00:00 GMT", "description": "This data set measures methane concentrations in ancient air trapped in the West Antarctic Ice Sheet (WAIS) Divide and Greenland Ice Sheet Project (GISP2) ice cores; presenting two, high-resolution ice core methane records of the past 2500 years, one from each pole. These measurements were used to reconstruct the methane Inter-Polar Difference (IPD) during the late Holocene. Also included are model results of methane emissions that were presented in the manuscript describing this data set.", "east": -38.5, "geometry": ["POINT(-38.5 72.6)", "POINT(-112.0865 -79.4676)"], "keywords": "Antarctica; Arctic; Chemistry:fluid; Chemistry:Fluid; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide; Arctic", "north": 72.6, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Mitchell, Logan E", "project_titles": "Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core.", "projects": [{"proj_uid": "p0000025", "repository": "USAP-DC", "title": "Collaborative Research: Constructing an Ultra-high Resolution Atmospheric Methane Record for the Last 140,000 Years from WAIS Divide Core."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.4676, "title": "Late Holocene Methane Concentrations from WAIS Divide and GISP2", "uid": "609586", "west": -112.0865}, {"awards": "1043690 Scherer, Reed", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: Diatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material.\nBroader impacts: This work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Biota; Diatom; Marine Sediments; Oceans; Sediment Core; Southern Ocean", "locations": "Antarctica; Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "Haji-Sheikh, Michael; Scherer, Reed Paul", "project_titles": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "projects": [{"proj_uid": "p0000360", "repository": "USAP-DC", "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "uid": "600127", "west": -180.0}, {"awards": "0439906 Koch, Paul", "bounds_geometry": ["POLYGON((162 -72,162.6 -72,163.2 -72,163.8 -72,164.4 -72,165 -72,165.6 -72,166.2 -72,166.8 -72,167.4 -72,168 -72,168 -72.6,168 -73.2,168 -73.8,168 -74.4,168 -75,168 -75.6,168 -76.2,168 -76.8,168 -77.4,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.4,162 -76.8,162 -76.2,162 -75.6,162 -75,162 -74.4,162 -73.8,162 -73.2,162 -72.6,162 -72))"], "date_created": "Fri, 01 Jan 2010 00:00:00 GMT", "description": "During previous NSF-sponsored research, the PI\u0027s discovered that southern elephant seal colonies once existed along the Victoria Land coast (VLC) of Antarctica, a region where they are no longer observed. Molted seal skin and hair occur along 300 km of coastline, more than 1000 km from any extant colony. The last record of a seal at a former colony site is at ~A.D. 1600. Because abandonment occurred prior to subantarctic sealing, disappearance of the VLC colony probably was due to environmental factors, possibly cooling and encroachment of land-fast, perennial sea ice that made access to haul-out sites difficult. The record of seal inhabitation along the VLC, therefore, has potential as a proxy for climate change. Elephant seals are a predominantly subantarctic species with circumpolar distribution. Genetic studies have revealed significant differentiation among populations, particularly with regard to that at Macquarie I., which is the extant population nearest to the abandoned VLC colony. Not only is the Macquarie population unique genetically, but it is has undergone unexplained decline of 2%/yr over the last 50 years3. In a pilot study, genetic analyses showed a close relationship between the VLC seals and those at Macquarie I. An understanding of the relationship between the two populations, as well as of the environmental pressures that led to the demise of the VLC colonies, will provide a better understanding of present-day population genetic structure, the effect of environmental change on seal populations, and possibly the reasons underlying the modern decline at Macquarie Island. This project addresses several key research problems: (1) Why did elephant seals colonize and then abandon the VLC? (2) What does the elephant seal record reveal about Holocene climate change and sea-ice conditions? (3) What were the foraging strategies of the seals and did these strategies change over time as climate varied? (4) How does the genetic structure of the VLC seals relate to extant populations? (5) How did genetic diversity change over time and with colony decline? (6) Using ancient samples to estimate mtDNA mutation rates, what can be learned about VLC population dynamics over time? (7) What was the ecological relationship between elephant seals and Adelie penguins that occupied the same sites, but apparently at different times? The proposed work includes the professional training of young researchers and incorporation of data into graduate and undergraduate courses.\n\nBecause of extreme isolation of the Antarctic continent since the \nEarly Oligocene, one expects a unique invertebrate benthic fauna with \na high degree of endemism. Yet some invertebrate taxa that constitute \nimportant ecological components of sedimentary benthic communities \ninclude more than 40 percent non-endemic species (e.g., benthic \npolychaetes). To account for non-endemic species, intermittent genetic \nexchange must occur between Antarctic and other (e.g. South American) \npopulations. The most likely mechanism for such gene flow, at least \nfor in-faunal and mobile macrobenthos, is dispersal of planktonic \nlarvae across the sub- Antarctic and Antarctic polar fronts. To test \nfor larval dispersal as a mechanism of maintaining genetic continuity \nacross polar fronts, the scientists propose to (1) take plankton \nsamples along transects across Drake passage during both the austral \nsummer and winter seasons while concurrently collecting the \nappropriate hydrographic data. Such data will help elucidate the \nhydrographic mechanisms that allow dispersal across Drake Passage. \nUsing a molecular phylogenetic approach, they will (2) compare \nseemingly identical adult forms from Antarctic and South America \ncontinents to identify genetic breaks, historical gene flow, and \ncontrol for the presence of cryptic species. (3) Similar molecular \ntools will be used to relate planktonic larvae to their adult forms. \nThrough this procedure, they propose to link the larval forms \nrespectively to their Antarctic or South America origins. The proposed \nwork builds on previous research that provides the basis for this \neffort to develop a synthetic understanding of historical gene flow \nand present day dispersal mechanism in South American/Drake Passage/ \nAntarctic Peninsular region. Furthermore, this work represents one of \nthe first attempts to examine recent gene flow in Antarctic benthic \ninvertebrates. Graduate students and a postdoctoral fellow will be \ntrained during this research\n", "east": 168.0, "geometry": ["POINT(165 -75)"], "keywords": "Biota; Isotope; Penguin; Ross Sea; Seals; Southern Ocean", "locations": "Southern Ocean; Ross Sea", "north": -72.0, "nsf_funding_programs": null, "persons": "Koch, Paul", "project_titles": "Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "projects": [{"proj_uid": "p0000533", "repository": "USAP-DC", "title": "Collaborative Research: Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Abandoned Elephant Seal Colonies in Antarctica: Integration of Genetic, Isotopic, and Geologic Approaches toward Understanding Holocene Environmental Change", "uid": "600041", "west": 162.0}, {"awards": "0520523 Brook, Edward J.", "bounds_geometry": ["POINT(-38.466667 73.583333)", "POINT(-148.81 -81.65)"], "date_created": "Wed, 09 Dec 2009 00:00:00 GMT", "description": "This data set contains methane measurements made in trapped air in the Holocene sections of two ice cores: the Siple Dome ice core in Antarctica, and the Greenland Ice Sheet Project 2 (GISP2) ice core in Greenland. The measurements were made at Oregon State University between 2007 and 2009. Measurements were made relative to the NOAA04 methane concentration scale using a working standard internally calibrated to NOAA certified air standards. Concentrations are corrected for gravitational fractionation and solubility effects in the melt-refreeze extraction. Data are available via FTP in Microsoft Excel (.xls) format.", "east": -38.466667, "geometry": ["POINT(-38.466667 73.583333)", "POINT(-148.81 -81.65)"], "keywords": "Antarctica; Arctic; Chemistry:fluid; Chemistry:Fluid; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "locations": "Arctic; Antarctica; Siple Dome", "north": 73.583333, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Brook, Edward J.", "project_titles": "Collaborative Research: New insights into the Holocene methane budget from dual isotope systematics and a high resolution record of the interpolar gradient", "projects": [{"proj_uid": "p0000131", "repository": "USAP-DC", "title": "Collaborative Research: New insights into the Holocene methane budget from dual isotope systematics and a high resolution record of the interpolar gradient"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.65, "title": "Methane Measurements from the GISP2 and Siple Dome Ice Cores", "uid": "609440", "west": -148.81}, {"awards": "0228052 Kreutz, Karl", "bounds_geometry": ["POLYGON((161.04 -77.3,161.239 -77.3,161.438 -77.3,161.637 -77.3,161.836 -77.3,162.035 -77.3,162.234 -77.3,162.433 -77.3,162.632 -77.3,162.831 -77.3,163.03 -77.3,163.03 -77.378,163.03 -77.456,163.03 -77.534,163.03 -77.612,163.03 -77.69,163.03 -77.768,163.03 -77.846,163.03 -77.924,163.03 -78.002,163.03 -78.08,162.831 -78.08,162.632 -78.08,162.433 -78.08,162.234 -78.08,162.035 -78.08,161.836 -78.08,161.637 -78.08,161.438 -78.08,161.239 -78.08,161.04 -78.08,161.04 -78.002,161.04 -77.924,161.04 -77.846,161.04 -77.768,161.04 -77.69,161.04 -77.612,161.04 -77.534,161.04 -77.456,161.04 -77.378,161.04 -77.3))"], "date_created": "Wed, 01 Jul 2009 00:00:00 GMT", "description": "This data set includes high-resolution ice core records from the Dry Valleys region of Antarctica, and provides interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). Intermediate-length ice cores (100 to 200 meters) were drilled at four sites along transects in the Taylor and Wright valleys, and analyzed for stable isotopes and major ions. The data set includes high-resolution ice core data for each study site. It also includes mass balance, borehole temperature, and snowpit data for each site, and Global Positioning System (GPS) velocity data for some of the sites. Snow pit data from three additional sites in the same region is also available. Data are available via FTP, in Microsoft Excel (.xls), ASCII text (.txt), and Microsoft Word (.doc) file formats.", "east": 163.03, "geometry": ["POINT(162.035 -77.69)"], "keywords": "Antarctica; Borehole Temperature; Chemistry:ice; Chemistry:Ice; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Mass Balance; Paleoclimate; Physical Properties", "locations": "Dry Valleys; Antarctica", "north": -77.3, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Kreutz, Karl; Mayewski, Paul A.", "project_titles": "Dry Valleys Late Holocene Climate Variability", "projects": [{"proj_uid": "p0000155", "repository": "USAP-DC", "title": "Dry Valleys Late Holocene Climate Variability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.08, "title": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "uid": "609399", "west": 161.04}, {"awards": "9316564 Mayewski, Paul", "bounds_geometry": ["POINT(-116.333 -78.733)", "POINT(-119.562 -80.014)", "POINT(-118.045 -79.461)"], "date_created": "Mon, 09 May 2005 00:00:00 GMT", "description": "The Ross Ice Drainage System (RIDS) project provides a high-resolution record of atmospheric chemical deposition taken from several ice cores and snow pits located at sites within or immediately adjacent to the Ross Ice Drainage System. Three sites were visited during a 1995 traverse in inland West Antarctica. The traverse was 158 km, trending 26\u00b0 from Byrd Surface Camp. The core from site A (78\u00b044\u0027S, 116\u00b020\u0027W) is 148 m deep, the core from site B (79\u00b027.66\u0027S, 118\u00b002.68\u0027W) is 60 m deep, and the core from site C (80\u00b000.85\u0027S, 119\u00b033.73\u0027W) is 60 m deep. Glaciochemical analysis focuses on the major ions deposited from the antarctic atmosphere, including Na (sodium), NH4 (ammonium), K (potassium), Mg (magnesium), Ca (calcium), Cl (chloride), NO3 (nitrate), and SO4 (sulfate). Chemical analysis also includes methanesulfonic acid (MSA) and nssSO4 (non-sea salt sulfate). The data are available by FTP in ASCII text format and Excel files.", "east": -116.333, "geometry": ["POINT(-116.333 -78.733)", "POINT(-119.562 -80.014)", "POINT(-118.045 -79.461)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; Snow Pit", "locations": "Antarctica", "north": -78.733, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Mayewski, Paul A.; Kreutz, Karl; Twickler, Mark; Whitlow, Sallie; Meeker, Loren D.", "project_titles": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability", "projects": [{"proj_uid": "p0000145", "repository": "USAP-DC", "title": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.014, "title": "Ross Ice Drainage System (RIDS) Glaciochemical Analysis", "uid": "609266", "west": -119.562}, {"awards": "9316564 Mayewski, Paul", "bounds_geometry": ["POINT(148.7725 -81.6425)"], "date_created": "Thu, 26 Aug 2004 00:00:00 GMT", "description": "This data set includes chemistry and ion data collected from a 150 m core recovered from Siple Dome, West Antarctica. The core was drilled during the 1994/1995 field season. Dating of the core was accomplished using annual signals preserved in several chemical species, beta activity profiles, and volcanic horizons. The resulting depth/age scale indicates an age of 1890 A.D. at 24 m, and 850 A.D. at 150 m depth.", "east": 148.7725, "geometry": ["POINT(148.7725 -81.6425)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "locations": "Antarctica; Siple Dome", "north": -81.6425, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Blunier, Thomas; Severinghaus, Jeffrey P.; Brook, Edward J.; Kreutz, Karl; Mayewski, Paul A.; Dunbar, Nelia", "project_titles": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability", "projects": [{"proj_uid": "p0000145", "repository": "NCEI", "title": "Ross Ice Drainage System (RIDS) Late Holocene Climate Variability"}], "repo": "NCEI", "repositories": "NCEI", "science_programs": "Siple Dome Ice Core", "south": -81.6425, "title": "Siple Dome Ice Core Chemistry and Ion Data", "uid": "609251", "west": 148.7725}, {"awards": "9615292 Wahlen, Martin", "bounds_geometry": ["POINT(158.71 -77.8)"], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "These data describe the concentration and carbon-isotopic composition (d13CO2) of atmospheric CO2 from air trapped in ice between 27,000 and 1,300 years before present from Taylor Dome, Antarctica. Data are used to investigate the causes of the CO2 concentration increase that occurred during the transition between the last glacial maximum (LGM) and the Holocene. Data are in tab-delimited ASCII and Excel formats, and are available via ftp.", "east": 158.71, "geometry": ["POINT(158.71 -77.8)"], "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "locations": "Antarctica; Taylor Dome", "north": -77.8, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Wahlen, Martin", "project_titles": "Carbon Dioxide and Carbon Isotopes in the Taylor Dome and Vostok Ice Cores", "projects": [{"proj_uid": "p0000153", "repository": "USAP-DC", "title": "Carbon Dioxide and Carbon Isotopes in the Taylor Dome and Vostok Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum", "uid": "609108", "west": 158.71}]

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