USAP-DC

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

[{"awards": "1745080 Gillikin, David; 1745057 Walker, Sally; 0739512 Walker, Sally; 1745064 Perez-Huerta, Alberto", "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": "1443105 Steig, Eric; 1141839 Steig, Eric; 1443397 Kreutz, Karl; 1443663 Cole-Dai, Jihong; 1443336 Osterberg, Erich", "bounds_geometry": ["POINT(-99 -90)"], "date_created": "Fri, 01 Dec 2023 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; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; Major Ion; Sea Ice; Sea Salt; Sodium; South Pole; SPICEcore", "locations": "South Pole; Antarctica; 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: 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": "South Pole Ice Core Sea Salt and Major Ions", "uid": "601754", "west": -99.0}, {"awards": "1744871 Robinson, Rebecca", "bounds_geometry": null, "date_created": "Wed, 30 Aug 2023 00:00:00 GMT", "description": "This dataset is the results of 3 experiments in which the spore-forming diatom Chaetoceros socialis was grown in culture and induced into resting spores by nitrate limitation. The nitrogen isotopic composition of accumulated biomass (\u03b415Nbiomass; \u2030 vs air) and of diatom-bound organic N (\u03b415Ndb; \u2030 vs air) are reported at two timepoints from each experiment: prior to and after resting spore formation. Experiments 1 and 2 provide measurements for CRS mixed with vegetative Chaetoceros cells, while Experiment 3 provides measurements for isolated CRS. Fluorescence and nitrate concentration was tracked throughout each experiment, with dissolved silica, ammonium, and total reduced nitrogen also measured in Experiment 3.", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Dove, Isabel", "project_titles": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?", "projects": [{"proj_uid": "p0010234", "repository": "USAP-DC", "title": "The nitrogen isotopic composition of diatom resting spores in Southern Ocean sediments: A source of bias and/or paleoenvironmental information?"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Dissolved nutrients, cell counts, and nitrogen isotope measurements from Chaetoceros socialis culture experiments", "uid": "601727", "west": null}, {"awards": "1543537 Priscu, John", "bounds_geometry": ["POINT(-149.50134 -84.640287)"], "date_created": "Wed, 01 Feb 2023 00:00:00 GMT", "description": "This dataset contains water column biogeochemical properties measured on discrete samples collected from Mercer Subglacial Lake by the SALSA project. Data included are: specific conductance; carbonic acid system parameters (total alkalinity, total inorganic carbon, and pH); water stable isotopes (\u03b42H and \u03b418O); dissolved gases (oxygen, methane, nitrous oxide, and hydrogen); dissolved nutrients (ammonium, nitrite and phosphate), major anions (including nitrate) and cations; size-fractionated colloidal and dissolved trace elements); dissolved organic carbon; and microbial cell and virus-like particle counts.", "east": -149.50134, "geometry": ["POINT(-149.50134 -84.640287)"], "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "locations": "Mercer Subglacial Lake; Mercer Subglacial Lake; West Antarctic Ice Sheet; Antarctica", "north": -84.640287, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Priscu, John; Science Team, SALSA", "project_titles": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "projects": [{"proj_uid": "p0010119", "repository": "USAP-DC", "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -84.640287, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "uid": "601663", "west": -149.50134}, {"awards": "1543450 Countway, Peter", "bounds_geometry": ["POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63))"], "date_created": "Tue, 03 Jan 2023 00:00:00 GMT", "description": "Dissolved inorganic nutrient samples were collected from Station E (Palmer Station, Antarctica) and associated incubation experiments with Station E water. Samples were analyzed for Nitrate plus Nitrite, Nitrite, Ammonium, Phosphate and Silicate. All nutrient analyses were performed at Bigelow Laboratory for Ocean Sciences. An overview of the analytical methods used for these analyses is included in a secondary tab with the uploaded data.", "east": -63.0, "geometry": ["POINT(-64.5 -64.5)"], "keywords": "Antarctica; Nitrate; Nitrite; Palmer Station; Phosphate", "locations": "Palmer Station; Antarctica", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Countway, Peter; Matrai, Patricia", "project_titles": "Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean", "projects": [{"proj_uid": "p0010120", "repository": "USAP-DC", "title": "Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -66.0, "title": "Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ", "uid": "601645", "west": -66.0}, {"awards": "2031442 Learman, Deric", "bounds_geometry": null, "date_created": "Thu, 08 Sep 2022 00:00:00 GMT", "description": "Shelf sediment samples were collected around the Antarctic Peninsular with the mega corer in 2020 (Nov. to Dec.). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set (10). ", "east": null, "geometry": null, "keywords": "Antarctica; Antarctic Peninsula; Grain Size; Grain Size Analysis; Marine Geoscience; Marine Sediments; Organic Matter Geochemistry; Sediment Core Data; Shelf Sediments; Weddell Sea", "locations": "Antarctic Peninsula; Weddell Sea; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Learman, Deric", "project_titles": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments", "projects": [{"proj_uid": "p0010235", "repository": "USAP-DC", "title": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "uid": "601607", "west": null}, {"awards": "1341464 Robinson, Rebecca", "bounds_geometry": ["POLYGON((-170.4 -60.8,-170.36 -60.8,-170.32 -60.8,-170.28 -60.8,-170.24 -60.8,-170.2 -60.8,-170.16 -60.8,-170.12 -60.8,-170.08 -60.8,-170.04 -60.8,-170 -60.8,-170 -61.34,-170 -61.88,-170 -62.42,-170 -62.96,-170 -63.5,-170 -64.04,-170 -64.58,-170 -65.12,-170 -65.66,-170 -66.2,-170.04 -66.2,-170.08 -66.2,-170.12 -66.2,-170.16 -66.2,-170.2 -66.2,-170.24 -66.2,-170.28 -66.2,-170.32 -66.2,-170.36 -66.2,-170.4 -66.2,-170.4 -65.66,-170.4 -65.12,-170.4 -64.58,-170.4 -64.04,-170.4 -63.5,-170.4 -62.96,-170.4 -62.42,-170.4 -61.88,-170.4 -61.34,-170.4 -60.8))"], "date_created": "Mon, 14 Feb 2022 00:00:00 GMT", "description": "Tracking variations in the surface ocean supply and demand of nitrate, a key marine nutrient, can help constrain the contribution of biological production in driving past climate shifts. The nitrogen isotopic composition (as \u03b415N) of organic matter in marine sediments is a proxy for surface ocean nitrate supply and demand over time but it may be subject to alteration during sinking and burial. The isotopic composition of nitrogen contained in the shells, or frustules, of diatoms (\u03b415NDB) is protected and is therefore a potentially more robust tracer of nitrate use in the past. Here we show that \u03b415NDB in Southern Ocean community cultures does not depend on species composition. We found the \u03b5DB (= biomass \u03b415N - \u03b415NDB) of the community growouts was -4.8 \u00b1 0.8\u2030, more than 10\u2030 different from previous monospecific growouts, but statistically indistinguishable from previous Southern Ocean and North Pacific surface ocean observations. The two community growouts, seeded with populations from 66\u00b0 and 61\u00b0S, had distinct community compositions but indistinguishable \u03b5DB, suggesting species composition does not primarily set \u03b415NDB values in the Southern Ocean. Our results demonstrate that under nitrate-replete conditions, \u03b415NDB values of frustules sinking from the surface ocean robustly track surface ocean nitrate \u03b415N values and therefore nitrate supply and demand. ", "east": -170.0, "geometry": ["POINT(-170.2 -63.5)"], "keywords": "Antarctica; Nitrogen Isotopes; Oceans; Paleoproxies; Southern Ocean", "locations": "Southern Ocean; Antarctica", "north": -60.8, "nsf_funding_programs": "Antarctic Earth Sciences", "persons": "Jones, Colin; Robinson, Rebecca; Brzezinski, Mark; Riesselman, Christina; Closset, Ivia; Kelly, Roger; Robinson, Rebecca ", "project_titles": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "projects": [{"proj_uid": "p0010083", "repository": "USAP-DC", "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -66.2, "title": "Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "uid": "601522", "west": -170.4}, {"awards": "1542723 Alexander, Becky", "bounds_geometry": ["POINT(-112.05 -79.28)"], "date_created": "Tue, 22 Jun 2021 00:00:00 GMT", "description": "This dataset contains measurements of nitrate oxygen (D17O) and nitrogen (d15N) isotopes from the WAIS Divide ice core (WDC06A). The time resolution is variable throughout the record. The data includes 15 discreet samples between 2900 - 67,000 years before 1950 and 305 continuous measurements between 36,000-52,000 years before 1950. The depth range is 700 - 3401 m. Each sample covered 1 m depth. The time resolution ranged from 5 years/m at the top to 200 years/m at the bottom.", "east": -112.05, "geometry": ["POINT(-112.05 -79.28)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Chemistry; Ice Core Records; Nitrate; Nitrate Isotopes; WAIS Divide Ice Core; West Antarctic Ice Sheet", "locations": "West Antarctic Ice Sheet; Antarctica", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Alexander, Becky", "project_titles": "Measuring an Ice-core Proxy for Relative Oxidant Abundances over Glacial-interglacial and Rapid Climate changes in a West Antarctic Ice Core", "projects": [{"proj_uid": "p0010403", "repository": "USAP-DC", "title": "Measuring an Ice-core Proxy for Relative Oxidant Abundances over Glacial-interglacial and Rapid Climate changes in a West Antarctic Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.28, "title": "WAIS Divide ice core nitrate isotopes", "uid": "601456", "west": -112.05}, {"awards": "1443663 Cole-Dai, Jihong", "bounds_geometry": ["POLYGON((-180 -89.99,-152.184 -89.99,-124.368 -89.99,-96.552 -89.99,-68.736 -89.99,-40.92 -89.99,-13.104 -89.99,14.712 -89.99,42.528 -89.99,70.344 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,98.16 -89.99,70.344 -89.99,42.528 -89.99,14.712 -89.99,-13.104 -89.99,-40.92 -89.99,-68.736 -89.99,-96.552 -89.99,-124.368 -89.99,-152.184 -89.99,180 -89.99,152.184 -89.99,124.368 -89.99,96.552 -89.99,68.736 -89.99,40.92 -89.99,13.104 -89.99,-14.712 -89.99,-42.528 -89.99,-70.344 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-98.16 -89.99,-70.344 -89.99,-42.528 -89.99,-14.712 -89.99,13.104 -89.99,40.92 -89.99,68.736 -89.99,96.552 -89.99,124.368 -89.99,152.184 -89.99,-180 -89.99))"], "date_created": "Sat, 30 Jan 2021 00:00:00 GMT", "description": "Major ion concentrations in SPICEcore samples from the section of 400-480 m were measured with ion chromatography. The ions are chloride, nitrate, sulfate, sodium, potassium, magnesium, and calcium.\r\nThis section was analyzed to replicate the measurement of the same section at Dartmouth College.", "east": -98.16, "geometry": ["POINT(-180 -89.99)"], "keywords": "Antarctica; Ions; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -89.99, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Cole-Dai, Jihong; Larrick, Carleigh", "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": -89.99, "title": "SPICEcore 400-480 m Major Ions SDSU", "uid": "601430", "west": 98.16}, {"awards": "1643684 Saito, Mak", "bounds_geometry": ["POLYGON((-180 -70,-173.5 -70,-167 -70,-160.5 -70,-154 -70,-147.5 -70,-141 -70,-134.5 -70,-128 -70,-121.5 -70,-115 -70,-115 -70.8,-115 -71.6,-115 -72.4,-115 -73.2,-115 -74,-115 -74.8,-115 -75.6,-115 -76.4,-115 -77.2,-115 -78,-121.5 -78,-128 -78,-134.5 -78,-141 -78,-147.5 -78,-154 -78,-160.5 -78,-167 -78,-173.5 -78,180 -78,179.2 -78,178.4 -78,177.6 -78,176.8 -78,176 -78,175.2 -78,174.4 -78,173.6 -78,172.8 -78,172 -78,172 -77.2,172 -76.4,172 -75.6,172 -74.8,172 -74,172 -73.2,172 -72.4,172 -71.6,172 -70.8,172 -70,172.8 -70,173.6 -70,174.4 -70,175.2 -70,176 -70,176.8 -70,177.6 -70,178.4 -70,179.2 -70,-180 -70))"], "date_created": "Wed, 20 Jan 2021 00:00:00 GMT", "description": "Nutrient from Amundsen Sea Ross Sea and Terra Nova Bay. Parameters include phosphate, N+N (nitrate + nitrite), silicic acid, nitrite and ammonia. Measured by Joe Jennings (OSU) using protocols described by Noble et al., 2012 (Limnol. Oceanogr.). Trace metal rosette CTD sensor data also included for bottle depths. ", "east": 172.0, "geometry": ["POINT(-151.5 -74)"], "keywords": "Amundsen Sea; Antarctica; NBP1801; Nitrate; Nitrite; Nutrients; Phosphate; Ross Sea; R/v Nathaniel B. Palmer; Silicic Acid; Terra Nova Bay", "locations": "Amundsen Sea; Ross Sea; Terra Nova Bay; Antarctica", "north": -70.0, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "Saito, Mak", "project_titles": "Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay", "projects": [{"proj_uid": "p0010045", "repository": "USAP-DC", "title": "Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Nutrients from NBP18-01 CICLOPS", "uid": "601428", "west": -115.0}, {"awards": "1341631 Lyons, W. Berry; 1341736 Adams, Byron", "bounds_geometry": ["POLYGON((-177.3907 -84.46466667,-177.06501 -84.46466667,-176.73932 -84.46466667,-176.41363 -84.46466667,-176.08794 -84.46466667,-175.76225 -84.46466667,-175.43656 -84.46466667,-175.11087 -84.46466667,-174.78518 -84.46466667,-174.45949 -84.46466667,-174.1338 -84.46466667,-174.1338 -84.566988336,-174.1338 -84.669310002,-174.1338 -84.771631668,-174.1338 -84.873953334,-174.1338 -84.976275,-174.1338 -85.078596666,-174.1338 -85.180918332,-174.1338 -85.283239998,-174.1338 -85.385561664,-174.1338 -85.48788333,-174.45949 -85.48788333,-174.78518 -85.48788333,-175.11087 -85.48788333,-175.43656 -85.48788333,-175.76225 -85.48788333,-176.08794 -85.48788333,-176.41363 -85.48788333,-176.73932 -85.48788333,-177.06501 -85.48788333,-177.3907 -85.48788333,-177.3907 -85.385561664,-177.3907 -85.283239998,-177.3907 -85.180918332,-177.3907 -85.078596666,-177.3907 -84.976275,-177.3907 -84.873953334,-177.3907 -84.771631668,-177.3907 -84.669310002,-177.3907 -84.566988336,-177.3907 -84.46466667))"], "date_created": "Sat, 02 Jan 2021 00:00:00 GMT", "description": "Soil samples were collected from the Shackleton Glacier region, located in the Queen Maud Mountains during the 2017-2018 austral summer. A subset of 27 samples were analyzed for stable isotopes of S, N, C, and O in nitrate, sulfate, and (bi)carbonate. ). \u03b415N-NO3 values ranged from -47.8 to 20.4\u2030 and, while all \u039417O-NO3 values are positive, they ranged from 15.7 to 45.9\u2030. \u03b434S-SO4 and \u03b418O-SO4 values ranged from 12.5 and 17.9\u2030 and -14.5 to -7.1\u2030, respectively. Total inorganic carbon isotopes ((bi)carbonate) in bulk soil samples ranged from 0.2 to 8.5\u2030 for \u03b413C and -38.8 to -9.6\u2030 for \u03b418O.", "east": -174.1338, "geometry": ["POINT(-175.76225 -84.976275)"], "keywords": "Antarctica; Geochemistry; Nitrate; Shackleton Glacier; Stable Isotopes; Sulfate; Transantarctic Mountains", "locations": "Transantarctic Mountains; Shackleton Glacier; Antarctica", "north": -84.46466667, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "persons": "Diaz, Melisa A.; Lyons, W. Berry; Gardner, Christopher B.", "project_titles": "Collaborative Research: The Role of Glacial History on the Structure and Functioning of Ecological Communities in the Shackleton Glacier Region of the Transantarctic Mountains", "projects": [{"proj_uid": "p0010140", "repository": "USAP-DC", "title": "Collaborative Research: The Role of Glacial History on the Structure and Functioning of Ecological Communities in the Shackleton Glacier Region of the Transantarctic Mountains"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -85.48788333, "title": "Shackleton Glacier region water-soluble salt isotopes", "uid": "601419", "west": -177.3907}, {"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": "0732917 McCormick, Michael", "bounds_geometry": ["POLYGON((299.4 -63.1,299.92 -63.1,300.44 -63.1,300.96 -63.1,301.48 -63.1,302 -63.1,302.52 -63.1,303.04 -63.1,303.56 -63.1,304.08 -63.1,304.6 -63.1,304.6 -63.29,304.6 -63.48,304.6 -63.67,304.6 -63.86,304.6 -64.05,304.6 -64.24,304.6 -64.43,304.6 -64.62,304.6 -64.81,304.6 -65,304.08 -65,303.56 -65,303.04 -65,302.52 -65,302 -65,301.48 -65,300.96 -65,300.44 -65,299.92 -65,299.4 -65,299.4 -64.81,299.4 -64.62,299.4 -64.43,299.4 -64.24,299.4 -64.05,299.4 -63.86,299.4 -63.67,299.4 -63.48,299.4 -63.29,299.4 -63.1))"], "date_created": "Sun, 17 Dec 2017 00:00:00 GMT", "description": "Ice-shelf loss along the east coast of the Antarctic Peninsula over recent decades has brought new sources of carbon and energy to the marine benthos likely affecting sediment geochemistry and microbial community composition. To better understand the long-term effects of ice-shelf loss on benthic microbial communities, we conducted a five-station survey along a 160 km transect following the historic path of retreat of the Larsen A ice shelf. All microbial community sequence data is publicly available through the Metagenomics Analysis Server at Argonne National Laboratory (MG-RAST). The project title is \"Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula\". A key word search using terms from this title at the MG-RAST portal (http://metagenomics.anl.gov/) will return the complete sample list. This submitted dataset summarizes the measured environmental parameters for these same samples (lat., long., water depth, sediment depth, pH, alkalinity, dissolved oxygen, silicate, phosphate, nitrate, nitrite, and ammonium).", "east": 304.6, "geometry": ["POINT(-58 -64.05)"], "keywords": "Antarctica; Antarctic Peninsula; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; LARISSA; Microbiology", "locations": "Antarctic Peninsula; Antarctica", "north": -63.1, "nsf_funding_programs": "Antarctic Integrated System Science", "persons": "McCormick, Michael", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems.", "projects": [{"proj_uid": "p0010135", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach - Marine Ecosystems."}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.0, "title": "LARISSA: Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula", "uid": "601073", "west": 299.4}, {"awards": "1246223 Hastings, Meredith", "bounds_geometry": ["POINT(-112.1115 -79.481)"], "date_created": "Wed, 26 Apr 2017 00:00:00 GMT", "description": "This dataset contains nitrate concentration and isotopic composition (d15N, d18O, D17O) measurements on the WAIS Divide WDC06A ice core.", "east": -112.1115, "geometry": ["POINT(-112.1115 -79.481)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Nitrate; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.481, "nsf_funding_programs": null, "persons": "Buffen, Aron; Hastings, Meredith", "project_titles": "Investigating Source, Chemistry and Climate changes using the Isotopic Composition of Nitrate in Antarctic Snow and Ice", "projects": [{"proj_uid": "p0000399", "repository": "USAP-DC", "title": "Investigating Source, Chemistry and Climate changes using the Isotopic Composition of Nitrate in Antarctic Snow and Ice"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "WAIS Divide WDC06A Nitrate Isotope Record", "uid": "601022", "west": -112.1115}, {"awards": "0538049 Steig, Eric", "bounds_geometry": ["POINT(-112.085 -79.5)"], "date_created": "Thu, 09 Mar 2017 00:00:00 GMT", "description": "This data set contain oxygen isotopes of sulfate and nitrate and nitrogen isotopes of nitrate from the WAIS Divide ice core from the surface to 577 m depth at varying resolution", "east": -112.085, "geometry": ["POINT(-112.085 -79.5)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Nitrate; Oxygen Isotope; Sulfate; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.5, "nsf_funding_programs": null, "persons": "Alexander, Becky; Steig, Eric J.", "project_titles": "Collaborative Research: Multiple-isotope Analysis of Nitrate and Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "projects": [{"proj_uid": "p0000020", "repository": "USAP-DC", "title": "Collaborative Research: Multiple-isotope Analysis of Nitrate and Sulfate in the West Antarctic Ice Sheet Divide Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.5, "title": "WAIS Divide sulfate and nitrate isotopes", "uid": "601007", "west": -112.085}, {"awards": "0636929 Bales, Roger", "bounds_geometry": ["POINT(-112.085 -79.467)"], "date_created": "Mon, 17 Mar 2014 00:00:00 GMT", "description": "This data set contains atmospheric mixing ratios of nitric oxide, ozone, hydrogen peroxide, methylhydroperoxide, and concentrations in surface snow and in snow pits of nitrate, nitrite, and hydrogen peroxide at the WAIS Divide deep ice-coring site.", "east": -112.085, "geometry": ["POINT(-112.085 -79.467)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -79.467, "nsf_funding_programs": null, "persons": "Bales, Roger", "project_titles": "Atmospheric, Snow and Firn Chemistry Studies for Interpretation of WAIS-Divide Cores", "projects": [{"proj_uid": "p0000041", "repository": "USAP-DC", "title": "Atmospheric, Snow and Firn Chemistry Studies for Interpretation of WAIS-Divide Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Measurements of Air and Snow Photochemical Species at WAIS Divide, Antarctica", "uid": "609585", "west": -112.085}, {"awards": "0337933 Cole-Dai, Jihong", "bounds_geometry": ["POINT(0 -90)"], "date_created": "Tue, 19 Nov 2013 00:00:00 GMT", "description": "A 180 m ice core drilled at South Pole in 2004/2005 was analyzed for concentrations of major ions at a depth resolution of approximately 2 cm. Measured ions are chloride, nitrate, sulfate, sodium, potassium, magnesium and calcium. The bottom of the core has been dated to 1830 years before 2004.", "east": 0.0, "geometry": ["POINT(0 -90)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ion Chromatograph; South Pole", "locations": "South Pole; Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Cole-Dai, Jihong", "project_titles": "Collaborative Research: Investigating Atmospheric Chemistry and Dynamics through Oxygen and Sulfur Isotopes in Volcanic Sulfate from South Pole Ice Cores", "projects": [{"proj_uid": "p0000031", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Atmospheric Chemistry and Dynamics through Oxygen and Sulfur Isotopes in Volcanic Sulfate from South Pole Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Major Ion Concentrations in 2004 South Pole Ice Core", "uid": "609542", "west": 0.0}, {"awards": "0230288 Anastasio, Cort", "bounds_geometry": ["POINT(-123.3 -75.1)"], "date_created": "Tue, 26 Jun 2012 00:00:00 GMT", "description": "This data set contains light absorption coefficients for soluble chromophores (light-absorbing chemicals) and concentrations of hydrogen peroxide (HOOH) and nitrate (NO3-) in ten snow samples that were collected in 2003 at Dome C, Antarctica.\n\nData are available via FTP.", "east": -123.3, "geometry": ["POINT(-123.3 -75.1)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Dome C Ice Core; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Physical Properties; Snow/ice; Snow/Ice", "locations": "Antarctica", "north": -75.1, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Anastasio, Cort; Robles, Tony", "project_titles": "Laboratory Studies of Photochemistry in Antarctic Snow and Ice", "projects": [{"proj_uid": "p0000175", "repository": "USAP-DC", "title": "Laboratory Studies of Photochemistry in Antarctic Snow and Ice"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Dome C Ice Core", "south": -75.1, "title": "Light Absorption Coefficients for Soluble Species in Snow, Dome C, Antarctica", "uid": "609519", "west": -123.3}, {"awards": "0538520 Thiemens, Mark", "bounds_geometry": ["POINT(-114.216667 -78.916667)"], "date_created": "Mon, 01 Nov 2010 00:00:00 GMT", "description": "This data set contains measurements of multiple sulfur and oxygen isotopes from sulfates, from an ice core drilled at the West Antarctic Ice Sheet (WAIS) Divide site in 2005. The initial sulfate measurements, analyzed in 2008 from the 70 meter WAIS 2005A core, are 12 meter averages and span the pre-industrial to industrial transition, from the late 1700s to 2005. This data set is part of the West Antarctic Ice Sheet Divide Ice Core (WAISCORES) project.\n\nData are available via FTP in Microsoft Excel (.xlsx) format.", "east": -114.216667, "geometry": ["POINT(-114.216667 -78.916667)"], "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS Divide; WAIS Divide Ice Core", "locations": "WAIS Divide; Antarctica", "north": -78.916667, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Thiemens, Mark H.", "project_titles": "Collaborative Research: Multiple-isotope Analysis of Nitrate and Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "projects": [{"proj_uid": "p0000020", "repository": "USAP-DC", "title": "Collaborative Research: Multiple-isotope Analysis of Nitrate and Sulfate in the West Antarctic Ice Sheet Divide Ice Core"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.916667, "title": "Multiple Isotope Analysis of Sulfate in the West Antarctic Ice Sheet Divide Ice Core", "uid": "609479", "west": -114.216667}, {"awards": "0125761 Thiemens, Mark", "bounds_geometry": ["POINT(139.2728 -89.9975)"], "date_created": "Wed, 01 Nov 2006 00:00:00 GMT", "description": "This data set contains snow pit measurements of oxygen isotopes, \u003csup\u003e17\u003c/sup\u003eO and \u003csup\u003e18\u003c/sup\u003eO, in nitrate and ion concentrations, and surface measurements of oxygen isotopes in nitrate and in nitrate aerosols from the Amundsen-Scott South Pole Station, Antarctica. The 6-meter snow pit provides investigators with a 25-year record of nitrate isotope variations and ion concentrations for a period spanning from 1979 to 2004. Monthly surface snow and weekly aerosol collections yield a year-long record of nitrate isotopic composition starting 01 December 2003 and ending 31 December 2004.\n\nLittle is known about the past denitrification of the stratosphere in high latitude regions. Such knowledge is important to understanding the chemical state of the ancient atmospheres and evaluating the present climate models. With this research, investigators aim to understand the denitrification of the Antarctic stratosphere and quantify the sources of nitrate aerosols over time.\n\nData are in Microsoft Excel format and are available via FTP.", "east": 139.2728, "geometry": ["POINT(139.2728 -89.9975)"], "keywords": "Aerosol; Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; NBP1502; Snow/ice; Snow/Ice; South Pole Station", "locations": "South Pole Station; Antarctica", "north": -89.9975, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Thiemens, Mark H.; Savarino, Joel", "project_titles": "South Pole Atmospheric Nitrate Isotopic Analysis (SPANIA)", "projects": [{"proj_uid": "p0000242", "repository": "USAP-DC", "title": "South Pole Atmospheric Nitrate Isotopic Analysis (SPANIA)"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -89.9975, "title": "Atmospheric Nitrate Isotopic Analysis at Amundsen-Scott South Pole Station, A Twenty-Five Year Record", "uid": "609281", "west": 139.2728}, {"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": "XXXXXXX Palais, Julie", "bounds_geometry": ["POLYGON((-120 -80,-118.5 -80,-117 -80,-115.5 -80,-114 -80,-112.5 -80,-111 -80,-109.5 -80,-108 -80,-106.5 -80,-105 -80,-105 -80.5,-105 -81,-105 -81.5,-105 -82,-105 -82.5,-105 -83,-105 -83.5,-105 -84,-105 -84.5,-105 -85,-106.5 -85,-108 -85,-109.5 -85,-111 -85,-112.5 -85,-114 -85,-115.5 -85,-117 -85,-118.5 -85,-120 -85,-120 -84.5,-120 -84,-120 -83.5,-120 -83,-120 -82.5,-120 -82,-120 -81.5,-120 -81,-120 -80.5,-120 -80))"], "date_created": "Thu, 16 Oct 2003 00:00:00 GMT", "description": "Glaciochemical and accumulation rate records developed from four ice cores in central West Antarctica are used to reconstruct former atmospheric circulation patterns in this region for the last 40 years with extended records (150-250 years) at two sites. The sites lie on a 200 km traverse from 82 degrees 22 minutes south, 119 degrees 17 minutes west to 81 degrees 22 minutes south, 107 degrees 17 minutes west, gaining elevation from 950 to 1930 m. The glaciochemical records represent the major ionic species present in Antarctic snow: sodium, potassium, magnesium, calcium, chloride, nitrate, and sulfate.", "east": -105.0, "geometry": ["POINT(-112.5 -82.5)"], "keywords": "Accumulation Rate; Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Snow/ice; Snow/Ice; West Antarctica", "locations": "West Antarctica; Antarctica", "north": -80.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Reusch, David", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": -85.0, "title": "Central West Antarctic Glaciochemistry from Ice Cores", "uid": "609093", "west": -120.0}]

View results on map Help on results map