USAP-DC

{"dp_type": "Project", "free_text": "Radioisotop"}

[{"awards": "2317997 Keogh, Molly", "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))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 17 Oct 2024 00:00:00 GMT", "description": "Climate change is disproportionately affecting polar regions, with the Arctic now warming nearly four times faster than the global average. Polar warming drives coastal erosion and increases sediment delivery to the coastal ocean, affecting ecosystem processes ranging from primary productivity to carbon sequestration. Tracking changes in sedimentation rate is urgently needed to determine current conditions and measure further change. In polar regions, however, two of the most globally reliable sediment tracers, the radioisotopes lead-210 (210Pb) and cesium-137 (137Cs), have yielded mixed results. To understand the distribution and usefulness of these radioisotopes at high latitudes, this research makes use of a wealth of polar sediment cores archived at the Oregon State University Marine and Geology Repository combined with data synthesized from the literature. Results provide the first systematic study of Arctic and Antarctic sediment accretion. Improving the tools we use to track changes in sedimentation will help coastal managers and decisionmakers understand how climate change is impacting polar coastlines and marine environments, and what local communities should expect in the future. Sediment cores will be subsampled and analyzed for the activities of 210Pb (half-life = 22.3 years) and 137Cs (half-life = 30.1 years) using alpha and gamma spectroscopy, respectively. To provide context related to depositional environment, select subsamples will also be analyzed for sediment bulk density, grain size distribution, and organic content. A subset of samples with no measurable 210Pb or 137Cs activity will be analyzed for 14C to determine whether the lack of radioisotopes in a sample is because the core is simply too old, the true surface layer is missing, or because the shorter-lived radioisotopes did not accumulate. By undertaking comprehensive spatial analysis of the distribution of 210Pb and 137Cs in Arctic and Antarctic sediments, this research will achieve three goals: first, measure the activity of short-lived radioisotopes in archived sediment cores, a service to the science community that is urgently needed before the isotopes decay beyond detection; second, produce a comprehensive pole-wide atlas of sediment accretion rates; and finally, conduct a temporal analysis of sedimentation rate changes over the last ~60 to 125 years along the Beaufort Sea coast of northern Alaska, an ecologically and economically important region experiencing environmental transformation due to climate warming. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Alpha Spectrometry; Sediment Dynamics; Polar; SEDIMENTATION; MARINE SEDIMENTS; Pb-210; Geochronology; SEDIMENTS", "locations": "Polar", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences; Post Doc/Travel", "paleo_time": null, "persons": "Keogh, Molly", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Postdoctoral Fellowship: OPP-PRF: Tracing Polar Sediments with Short-lived Radioisotopes in 75 years of Arctic and Antarctic Sediment Cores", "uid": "p0010484", "west": -180.0}, {"awards": "2423761 Blackburn, Terrence", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "datasets": [{"dataset_uid": "601918", "doi": "10.15784/601918", "keywords": "Antarctica; Carbon Isotopes; Cryosphere; East Antarctica; Elephant Moraine; Geochronology; Isotope Data; Subglacial", "people": "Piccione, Gavin", "repository": "USAP-DC", "science_program": null, "title": "Thermogenic Methane Production in Antarctic Subglacial Hydrocarbon Seeps", "url": "https://www.usap-dc.org/view/dataset/601918"}], "date_created": "Tue, 14 May 2024 00:00:00 GMT", "description": "Non-technical abstract Earth\u2019s climatic changes have been recorded in the ice core collected from the Antarctic ice sheet. While these records provide a high resolution view of how polar temperatures changed through time, it is not always clear what Earth process influence Antarctic climate. One likely contributor to Antarctic temperature changes is the cyclic changes in Earth\u2019s orientation as it orbits the sun. These so-called Milankovitch cycles control the amount and pattern of sunlight reaching the polar regions, that in turn result in periods of climatic warming or cooling. While the orbital variations and control on incoming solar energy remain well understood, how they influence Antarctic climate remains unresolved. It is the goal of this project to determine how variations in Earth\u2019s orbit may be locally influencing Antarctic temperatures. The researchers on this project are pursing this goal by identifying periods of past ice melting on the surface of Antarctica using minerals that precipitate from the meltwaters that resulted from past warm periods. The timing of this past melting will be determined by radioisotopic dating of the minerals using the natural radioactive decay of uranium to thorium. By dating numerous samples, collected in past scientific expeditions throughout the Antarctic continent, these researchers aim to reconstruct the frequency and spatial pattern of past warming and in doing so, determine what aspect of Earth\u2019s orbital variations influences Antarctic ice loss. Technical abstract Antarctic ice cores provide high resolution records of Pleistocene Southern Hemisphere temperatures that show an overall coherence with Northern Hemisphere temperature variations. One explanation for this bi-hemispheric temperature covariance relies on changes in atmospheric CO2 that result from varying northern hemisphere insolation. An alternative posits that the apparent coherence of polar temperatures is due to the misleading covariance between northern hemisphere summer insolation and, the southern hemisphere summer duration. At present there is an insufficient understanding of the role that local insolation plays in Antarctic climate. The goal of this research project is to identify the temporal spatial patterns of solar forcing in Antarctica. To reach this goal, the project team will: 1) develop a way to identify periods of past surface melt production in Antarctica using U-Th dating of pedogenic carbonates; and 2) utilize the evidence of past surface melting to calibrate energy balance models and interrogate past Antarctic surface temperatures and; 3) compare the timing of Antarctic warm periods to potential solar forcing mechanisms such as peak summer insolation or summer duration. A means of identifying the spatial and temporal pattern at which local insolation influences Antarctic temperature would provide a transformative solution to the contradiction in current climate records. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Ice Sheet; PALEOCLIMATE RECONSTRUCTIONS", "locations": "Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Blackburn, Terrence", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "EAGER: Pedogenic Carbonates Record Insolation Driven Surface Melting in Antarctica", "uid": "p0010459", "west": -180.0}, {"awards": "1443585 Polito, Michael; 1443386 Emslie, Steven; 1826712 McMahon, Kelton; 1443424 McMahon, Kelton", "bounds_geometry": "POLYGON((-180 -60,-166 -60,-152 -60,-138 -60,-124 -60,-110 -60,-96 -60,-82 -60,-68 -60,-54 -60,-40 -60,-40 -61.8,-40 -63.6,-40 -65.4,-40 -67.2,-40 -69,-40 -70.8,-40 -72.6,-40 -74.4,-40 -76.2,-40 -78,-54 -78,-68 -78,-82 -78,-96 -78,-110 -78,-124 -78,-138 -78,-152 -78,-166 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -76.2,160 -74.4,160 -72.6,160 -70.8,160 -69,160 -67.2,160 -65.4,160 -63.6,160 -61.8,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions; Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s; Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica; Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009; Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula; 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.; 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; Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.; Receding ice drove parallel expansions in Southern Ocean penguin; SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".; Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica; Stable isotopes of Adelie Penguin chick bone collagen; The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "datasets": [{"dataset_uid": "601509", "doi": "10.15784/601509", "keywords": "Antarctica; Antarctic Fur Seal; Elemental Concentrations; King Penguin; Population Dynamics; South Atlantic Ocean; South Georgia Island; Stable Isotope Analysis; Sub-Antarctic", "people": "Maiti, Kanchan; Kristan, Allyson; McMahon, Kelton; Polito, Michael", "repository": "USAP-DC", "science_program": null, "title": "Radiometric dating, geochemical proxies, and predator biological remains obtained from aquatic sediment cores on South Georgia Island.", "url": "https://www.usap-dc.org/view/dataset/601509"}, {"dataset_uid": "601760", "doi": "10.15784/601760", "keywords": "Adelie Penguin; Amino Acids; Antarctica; Antarctic Peninsula; Ross Sea; Stable Isotope Analysis; Trophic Position", "people": "Emslie, Steven D.; McMahon, Kelton; Patterson, William; McCarthy, Matthew; Wonder, Michael; Polito, Michael; Michelson, Chantel", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of modern and ancient Ad\u00e9lie penguin eggshells from the Ross Sea and Antarctic Peninsula regions", "url": "https://www.usap-dc.org/view/dataset/601760"}, {"dataset_uid": "601364", "doi": "10.15784/601364", "keywords": "Antarctica; Antarctic Peninsula; Arctocephalus Gazella; Carbon; Holocene; Nitrogen; Paleoecology; Penguin; Pygoscelis Spp.; Stable Isotope Analysis; Weddell Sea", "people": "Clucas, Gemma; Herman, Rachael; Polito, Michael; Kalvakaalva, Rohit", "repository": "USAP-DC", "science_program": null, "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.", "url": "https://www.usap-dc.org/view/dataset/601364"}, {"dataset_uid": "601263", "doi": "10.15784/601263", "keywords": "Abandoned Colonies; Antarctica; Holocene; Penguin; Ross Sea; Stable Isotope Analysis", "people": "Kristan, Allyson; Emslie, Steven D.; Patterson, William", "repository": "USAP-DC", "science_program": null, "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", "url": "https://www.usap-dc.org/view/dataset/601263"}, {"dataset_uid": "200181", "doi": "10.6084/m9.figshare.c.4475300.v1", "keywords": null, "people": null, "repository": "Figshare", "science_program": null, "title": "SNP data from \"Receding ice drove parallel expansions in Southern Ocean penguins\".", "url": "https://doi.org/10.6084/m9.figshare.c.4475300.v1"}, {"dataset_uid": "601913", "doi": "10.15784/601913", "keywords": "Adelie Penguin; Antarctica; Cryosphere; Foraging; Polynya; Pygoscelis Adeliae; Ross Sea; Stable Isotopes", "people": "Emslie, Steven D.; Powers, Shannon; Reaves, Megan", "repository": "USAP-DC", "science_program": null, "title": "Stable isotopes of Adelie Penguin chick bone collagen", "url": "https://www.usap-dc.org/view/dataset/601913"}, {"dataset_uid": "200180", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "Receding ice drove parallel expansions in Southern Ocean penguin", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA589336"}, {"dataset_uid": "601232", "doi": "10.15784/601232", "keywords": "Amino Acids; Antarctica; Antarctic Peninsula; Biota; Isotope Data; Nitrogen Isotopes; Oceans; Penguin; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael; McMahon, Kelton", "repository": "USAP-DC", "science_program": null, "title": "Amino acid nitrogen isotope values of penguins from the Antarctic Peninsula region 1930s to 2010s", "url": "https://www.usap-dc.org/view/dataset/601232"}, {"dataset_uid": "601374", "doi": "10.15784/601374", "keywords": "Adelie Penguin; Antarctica; Cape Irizar; Drygalski Ice Tongue; Ross Sea; Stable Isotopes", "people": "Emslie, Steven D.", "repository": "USAP-DC", "science_program": null, "title": "Ancient Adelie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601374"}, {"dataset_uid": "601212", "doi": "10.15784/601212", "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", "people": "Emslie, Steven D.", "repository": "USAP-DC", "science_program": null, "title": "Radiocarbon dates from pygoscelid penguin tissues excavated at Stranger Point, King George Island, Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601212"}, {"dataset_uid": "601210", "doi": "10.15784/601210", "keywords": "Antarctica; Antarctic Krill; Antarctic Peninsula; Biota; Carbon Isotopes; Isotope Data; Krill; Nitrogen Isotopes; Oceans; Southern Ocean; Stable Isotope Analysis", "people": "Polito, Michael", "repository": "USAP-DC", "science_program": null, "title": "Carbon and nitrogen stable isotope values of Antarctic Krill from the South Shetland Islands and the northern Antarctic Peninsula 2007 and 2009", "url": "https://www.usap-dc.org/view/dataset/601210"}, {"dataset_uid": "601327", "doi": "10.15784/601327", "keywords": "Adelie Penguin; Antarctica; Biota; Cape Adare; East Antarctica; Population Movement; Pygoscelis Adeliae; Radiocarbon; Ross Sea; Sea Level Rise; Stable Isotopes", "people": "Emslie, Steven D.; McKenzie, Ashley; Patterson, William", "repository": "USAP-DC", "science_program": null, "title": "The rise and fall of an ancient Adelie penguin \u0027supercolony\u0027 at Cape Adare, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601327"}, {"dataset_uid": "601382", "doi": "10.15784/601382", "keywords": "25 De Mayo/King George Island; Antarctica; Biota; Delta 13C; Delta 15N; Dietary Shifts; Opportunistic Sampling; Penguin; Pygoscelis Penguins; Stranger Point", "people": "Emslie, Steven D.; Ciriani, Yanina", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica", "url": "https://www.usap-dc.org/view/dataset/601382"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (\u003c20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change. This research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.", "east": -40.0, "geometry": "POINT(-120 -69)", "instruments": null, "is_usap_dc": true, "keywords": "ANIMAL ECOLOGY AND BEHAVIOR; South Shetland Islands; Penguin; Stable Isotopes; Polar; Ross Sea; USA/NSF; Weddell Sea; AMD; MARINE ECOSYSTEMS; USAP-DC; Antarctica; PENGUINS; Southern Hemisphere; FIELD INVESTIGATION; Amd/Us; Krill; MACROFOSSILS", "locations": "Southern Hemisphere; Ross Sea; South Shetland Islands; Weddell Sea; Polar; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Polito, Michael; Kelton, McMahon; Patterson, William; McCarthy, Matthew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "Figshare; NCBI BioProject; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "uid": "p0010047", "west": 160.0}, {"awards": "1644073 DiTullio, Giacomo; 1643684 Saito, Mak", "bounds_geometry": "POLYGON((-180 -72,-173.6 -72,-167.2 -72,-160.8 -72,-154.4 -72,-148 -72,-141.6 -72,-135.2 -72,-128.8 -72,-122.4 -72,-116 -72,-116 -72.7,-116 -73.4,-116 -74.1,-116 -74.8,-116 -75.5,-116 -76.2,-116 -76.9,-116 -77.6,-116 -78.3,-116 -79,-122.4 -79,-128.8 -79,-135.2 -79,-141.6 -79,-148 -79,-154.4 -79,-160.8 -79,-167.2 -79,-173.6 -79,180 -79,178 -79,176 -79,174 -79,172 -79,170 -79,168 -79,166 -79,164 -79,162 -79,160 -79,160 -78.3,160 -77.6,160 -76.9,160 -76.2,160 -75.5,160 -74.8,160 -74.1,160 -73.4,160 -72.7,160 -72,162 -72,164 -72,166 -72,168 -72,170 -72,172 -72,174 -72,176 -72,178 -72,-180 -72))", "dataset_titles": "Algal pigment concentrations from the Ross Sea; Biogenic silica concentrations from the Ross Sea; NBP1801 Expedition data; Nutrients from NBP18-01 CICLOPS", "datasets": [{"dataset_uid": "601205", "doi": "10.15784/601205", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Chlorophyll; Chromatography; Liquid Chromatograph; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Seawater Measurements; Southern Ocean; Water Measurements; Water Samples", "people": "Ditullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Algal pigment concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601205"}, {"dataset_uid": "200056", "doi": "10.7284/907753", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1801 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1801"}, {"dataset_uid": "601225", "doi": "10.15784/601225", "keywords": "Antarctica; Biogenic Silica; Biogenic Silica Concentrations; Chemistry:Water; Geochemistry; NBP1801; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Water; Southern Ocean; Spectroscopy; Water Measurements; Water Samples", "people": "Schanke, Nicole; Ditullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Biogenic silica concentrations from the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/601225"}, {"dataset_uid": "601428", "doi": "10.15784/601428", "keywords": "Amundsen Sea; Antarctica; NBP1801; Nitrate; Nitrite; Nutrients; Phosphate; Ross Sea; R/v Nathaniel B. Palmer; Silicic Acid; Terra Nova Bay", "people": "Saito, Mak", "repository": "USAP-DC", "science_program": null, "title": "Nutrients from NBP18-01 CICLOPS", "url": "https://www.usap-dc.org/view/dataset/601428"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "Phytoplankton blooms in the coastal waters of the Ross Sea, Antarctica are typically dominated by either diatoms or Phaeocystis Antarctica (a flagellated algae that often can form large colonies in a gelatinous matrix). The project seeks to determine if an association of bacterial populations with Phaeocystis antarctica colonies can directly supply Phaeocystis with Vitamin B12, which can be an important co-limiting micronutrient in the Ross Sea. The supply of an essential vitamin coupled with the ability to grow at lower iron concentrations may put Phaeocystis at a competitive advantage over diatoms. Because Phaeocystis cells can fix more carbon than diatoms and Phaeocystis are not grazed as efficiently as diatoms, the project will help in refining understanding of carbon dynamics in the region as well as the basis of the food web webs. Such understanding also has the potential to help refine predictive ecological models for the region. The project will conduct public outreach activities and will contribute to undergraduate and graduate research. Engagement of underrepresented students will occur during summer student internships. A collaboration with Italian Antarctic researchers, who have been studying the Terra Nova Bay ecosystem since the 1980s, aims to enhance the project and promote international scientific collaborations. The study will test whether a mutualistic symbioses between attached bacteria and Phaeocystis provides colonial cells a mechanism for alleviating chronic Vitamin B12 co-limitation effects thereby conferring them with a competitive advantage over diatom communities. The use of drifters in a time series study will provide the opportunity to track in both space and time a developing algal bloom in Terra Nova Bay and to determine community structure and the physiological nutrient status of microbial populations. A combination of flow cytometry, proteomics, metatranscriptomics, radioisotopic and stable isotopic labeling experiments will determine carbon and nutrient uptake rates and the role of bacteria in mitigating potential vitamin B12 and iron limitation. Membrane inlet and proton transfer reaction mass spectrometry will also be used to estimate net community production and release of volatile organic carbon compounds that are climatically active. Understanding how environmental parameters can influence microbial community dynamics in Antarctic coastal waters will advance an understanding of how changes in ocean stratification and chemistry could impact the biogeochemistry and food web dynamics of Southern Ocean ecosystems.", "east": 160.0, "geometry": "POINT(-158 -75.5)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; NBP1801; Amd/Us; USA/NSF; USAP-DC; NUTRIENTS; PIGMENTS; CHLOROPHYLL; R/V NBP; Ross Sea; AMD", "locations": "Ross Sea", "north": -72.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "DiTullio, Giacomo; Lee, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -79.0, "title": "Collaborative Research: Cobalamin and Iron Co-Limitation Of Phytoplankton Species in Terra Nova Bay", "uid": "p0010045", "west": -116.0}, {"awards": "1341669 DeMaster, David", "bounds_geometry": "POLYGON((-70 -62,-68.8 -62,-67.6 -62,-66.4 -62,-65.2 -62,-64 -62,-62.8 -62,-61.6 -62,-60.4 -62,-59.2 -62,-58 -62,-58 -62.6,-58 -63.2,-58 -63.8,-58 -64.4,-58 -65,-58 -65.6,-58 -66.2,-58 -66.8,-58 -67.4,-58 -68,-59.2 -68,-60.4 -68,-61.6 -68,-62.8 -68,-64 -68,-65.2 -68,-66.4 -68,-67.6 -68,-68.8 -68,-70 -68,-70 -67.4,-70 -66.8,-70 -66.2,-70 -65.6,-70 -65,-70 -64.4,-70 -63.8,-70 -63.2,-70 -62.6,-70 -62))", "dataset_titles": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data; Expedition Data of NBP1203; Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "datasets": [{"dataset_uid": "001438", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1203", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601304", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1203; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601304"}, {"dataset_uid": "601319", "doi": "10.15784/601319", "keywords": "Antarctica; Antarctic Peninsula; Biota; Bioturbation Coefficients; Diagenesis; Labile Organic Carbon; LOC Mean Residence Times; Marguerite Bay; Oceans; Organic Carbon Degradation Rates; Sediment Core", "people": "Isla, Enrique; Taylor, Richard; Smith, Craig; Thomas, Carrie; DeMaster, David", "repository": "USAP-DC", "science_program": null, "title": "Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf", "url": "https://www.usap-dc.org/view/dataset/601319"}, {"dataset_uid": "601082", "doi": "10.15784/601082", "keywords": null, "people": "DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data", "url": "https://www.usap-dc.org/view/dataset/601082"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}], "date_created": "Sat, 03 Feb 2018 00:00:00 GMT", "description": "Intellectual Merit: The PI requests support to analyze sediments from multi-cores and mega-cores previously collected from beneath the former Larsen B and Larsen A ice shelves. These unique cores will allow the PI to develop a time-integrated understanding of the benthic response to ice shelf collapse off the East Antarctic Peninsula over time periods as short as 5 years following ice shelf collapse up to \u003e170 years after collapse. High latitudes are responding to climate change more rapidly than the rest of the planet and the disappearance of ice shelves are a key manifestation of climate warming. The PI will investigate the newly created benthic environments and associated ecosystems that have resulted from the re-initiation of fresh planktonic material to the sediment-water interface. This proposal will use a new geochemical technique, based on naturally occurring 14C that can be used to assess the distribution and inventory of recently produced organic carbon accumulating in the sediments beneath the former Larsen A and B ice shelves. The PI will couple 14C measurements with 210Pb analyses to assess turnover times for sedimentary labile organic matter. By comparing the distributions and inventories of labile organic matter as well as the bioturbation intensities among different locations as a function of time following ice shelf collapse/retreat, the nature and timing of the benthic response to ice shelf collapse can be assessed. Broader impacts: This study will provide important information characterizing changes occurring on the seafloor after the collapse of ice shelves. This research will support the research project of a graduate student. This project brings together researchers from both the European community and the LARISSA Project.", "east": -58.0, "geometry": "POINT(-64 -65)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Pb-210; C-14; NBP1203; Radioisotop; USAP-DC; R/V NBP; Species Abundance; Labile Organic Carbon; LABORATORY", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "DeMaster, David; Smith, Craig", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": "LARISSA", "south": -68.0, "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "uid": "p0000382", "west": -70.0}, {"awards": "0732602 Truffer, Martin; 0732655 Mosley-Thompson, Ellen; 0732651 Gordon, Arnold; 0732625 Leventer, Amy; 0732711 Smith, Craig; 0732983 Vernet, Maria", "bounds_geometry": "POLYGON((-68 -57.8,-66.78 -57.8,-65.56 -57.8,-64.34 -57.8,-63.12 -57.8,-61.9 -57.8,-60.68 -57.8,-59.46 -57.8,-58.24 -57.8,-57.02 -57.8,-55.8 -57.8,-55.8 -58.8,-55.8 -59.8,-55.8 -60.8,-55.8 -61.8,-55.8 -62.8,-55.8 -63.8,-55.8 -64.8,-55.8 -65.8,-55.8 -66.8,-55.8 -67.8,-57.02 -67.8,-58.24 -67.8,-59.46 -67.8,-60.68 -67.8,-61.9 -67.8,-63.12 -67.8,-64.34 -67.8,-65.56 -67.8,-66.78 -67.8,-68 -67.8,-68 -66.8,-68 -65.8,-68 -64.8,-68 -63.8,-68 -62.8,-68 -61.8,-68 -60.8,-68 -59.8,-68 -58.8,-68 -57.8))", "dataset_titles": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems; Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203; Bruce Plateau Accumulation O18 2009-1900; Easten Antarctic Peninsula Surface Sediment Diatom Data; LMG13-11 JKC-1 Paleoceanographic data; Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001; NBP1001 cruise data; NBP1203 cruise data; Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001; Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Sediment samples (full data link not provided)", "datasets": [{"dataset_uid": "601305", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Megafauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601305"}, {"dataset_uid": "601348", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed CTD Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601348"}, {"dataset_uid": "601347", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; LARISSA; Larsen Ice Shelf; NBP1203; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": null, "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf near Antarctica acquired during the Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601347"}, {"dataset_uid": "601346", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Current Measurements; LADCP; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer", "people": "Gordon, Arnold; Huber, Bruce", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed ship-based LADCP Sonar Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601346"}, {"dataset_uid": "000143", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1203 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601345", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; CTD; CTD Data; LARISSA; Larsen Ice Shelf; NBP1001; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; Salinity; Temperature", "people": "Huber, Bruce; Gordon, Arnold", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Processed CTD Data from the Larsen Ice Shelf in Antarctica acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601345"}, {"dataset_uid": "600167", "doi": "10.15784/600167", "keywords": "Antarctica; Antarctic Peninsula; Bruce Plateau; Glaciology; Ice Core Records; Isotope; LARISSA; Paleoclimate; Sample/collection Description; Sample/Collection Description; Snow Accumulation", "people": "Mosley-Thompson, Ellen; Thompson, Lonnie G.", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Bruce Plateau Accumulation O18 2009-1900", "url": "https://www.usap-dc.org/view/dataset/600167"}, {"dataset_uid": "000142", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1001 cruise data", "url": "https://www.rvdata.us/search/cruise/NBP1001"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}, {"dataset_uid": "601485", "doi": "10.15784/601485", "keywords": "Antarctica; Antarctic Peninsula; Delta 13C; Delta 18O; Paleoceanography; Temperature", "people": "Shevenell, Amelia", "repository": "USAP-DC", "science_program": "LARISSA", "title": "LMG13-11 JKC-1 Paleoceanographic data", "url": "https://www.usap-dc.org/view/dataset/601485"}, {"dataset_uid": "600073", "doi": "10.15784/600073", "keywords": "Antarctica; Antarctic Peninsula; Araon1304; Biota; LARISSA; Larsen B Ice Shelf; NBP1001; NBP1203; Oceans; Physical Oceanography; Southern Ocean; Weddell Sea", "people": "Vernet, Maria", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Abrupt Environmental Change in the Larsen Ice Shelf System (LARISSA) - Marine Ecosystems", "url": "https://www.usap-dc.org/view/dataset/600073"}, {"dataset_uid": "000226", "doi": "", "keywords": null, "people": null, "repository": "MGDS", "science_program": null, "title": "Biology Species Abundance from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expeditions NBP1001 and NBP1203", "url": "https://doi.org/10.1594/ieda/320821"}, {"dataset_uid": "601211", "doi": "10.15784/601211", "keywords": "Antarctica; Antarctic Peninsula; Benthos; Biota; Diatom; Geology/Geophysics - Other; LMG0502; Marine Geoscience; Marine Sediments; Microscope; NBP0003; NBP0107; NBP0603; NBP1203; R/v Nathaniel B. Palmer; Surface Sediment", "people": "Leventer, Amy", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Easten Antarctic Peninsula Surface Sediment Diatom Data", "url": "https://www.usap-dc.org/view/dataset/601211"}, {"dataset_uid": "000145", "doi": "", "keywords": null, "people": null, "repository": "AMGRF", "science_program": null, "title": "Sediment samples (full data link not provided)", "url": "http://arf.fsu.edu/"}, {"dataset_uid": "601306", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biota; Box Corer; LARISSA; Larsen Ice Shelf; Macrofauna; NBP1001; Oceans; R/v Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Macrofauna Species Abundance Raw Data from the Larsen Ice Shelf acquired during the Nathaniel B. Palmer expedition NBP1001", "url": "https://www.usap-dc.org/view/dataset/601306"}], "date_created": "Thu, 01 Feb 2018 00:00:00 GMT", "description": "Like no other region on Earth, the northern Antarctic Peninsula represents a spectacular natural laboratory of climate change and provides the opportunity to study the record of past climate and ecological shifts alongside the present-day changes in one of the most rapidly warming regions on Earth. This award supports the cryospheric and oceano-graphic components of an integrated multi-disciplinary program to address these rapid and fundamental changes now taking place in Antarctic Peninsula (AP). By making use of a marine research platform (the RV NB Palmer and on-board helicopters) and additional logistical support from the Argentine Antarctic program, the project will bring glaciologists, oceanographers, marine geologists and biologists together, working collaboratively to address fundamentally interdisciplinary questions regarding climate change. The project will include gathering a new, high-resolution paleoclimate record from the Bruce Plateau of Graham Land, and using it to compare Holocene- and possibly glacial-epoch climate to the modern period; investigating the stability of the remaining Larsen Ice Shelf and rapid post-breakup glacier response ? in particular, the roles of surface melt and ice-ocean interactions in the speed-up and retreat; observing the contribution of, and response of, oceanographic systems to ice shelf disintegration and ice-glacier interactions. Helicopter support on board will allow access to a wide range of glacial and geological areas of interest adjacent to the Larsen embayment. At these locations, long-term in situ glacial monitoring, isostatic uplift, and ice flow GPS sites will be established, and high-resolution ice core records will be obtained using previously tested lightweight drilling equipment. Long-term monitoring of deep water outflow will, for the first time, be integrated into changes in ice shelf extent and thickness, bottom water formation, and multi-level circulation by linking near-source observations to distal sites of concentrated outflow. The broader impacts of this international, multidisciplinary effort are that it will significantly advance our understanding of linkages amongst the earth\u0027s systems in the Polar Regions, and are proposed with international participation (UK, Spain, Belgium, Germany and Argentina) and interdisciplinary engagement in the true spirit of the International Polar Year (IPY). It will also provide a means of engaging and educating the public in virtually all aspects of polar science and the effects of ongoing climate change. The research team has a long record of involving undergraduates in research, educating high-performing graduate students, and providing innovative and engaging outreach products to the K-12 education and public media forums. Moreover, forging the new links both in science and international Antarctic programs will provide a continuing legacy, beyond IPY, of improved understanding and cooperation in Antarctica.", "east": -55.8, "geometry": "POINT(-61.9 -62.8)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e BOX CORE; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e ICE AUGERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SNOW DENSITY CUTTER", "is_usap_dc": true, "keywords": "Paleoclimate; Megafauna; USAP-DC; AMD; Amd/Us; Antarctica; Climate Change; LABORATORY; Climate Variability; Multi-Disciplinary; Cryosphere; NBP1001; FIELD SURVEYS; Not provided; Antarctic Peninsula; R/V NBP; FIELD INVESTIGATION; USA/NSF; Ice Core; Holocene", "locations": "Antarctica; Antarctic Peninsula", "north": -57.8, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Organisms and Ecosystems", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Truffer, Martin; Gordon, Arnold; Huber, Bruce; Mosley-Thompson, Ellen; Leventer, Amy; Vernet, Maria; Smith, Craig; Thompson, Lonnie G.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "AMGRF; MGDS; R2R; USAP-DC", "science_programs": "LARISSA", "south": -67.8, "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "uid": "p0000101", "west": -68.0}, {"awards": "1241460 Barbeau, David; 1241574 Hemming, Sidney", "bounds_geometry": "POLYGON((-67 -63.2,-65.97 -63.2,-64.94 -63.2,-63.91 -63.2,-62.88 -63.2,-61.85 -63.2,-60.82 -63.2,-59.79 -63.2,-58.76 -63.2,-57.73 -63.2,-56.7 -63.2,-56.7 -63.54,-56.7 -63.88,-56.7 -64.22,-56.7 -64.56,-56.7 -64.9,-56.7 -65.24,-56.7 -65.58,-56.7 -65.92,-56.7 -66.26,-56.7 -66.6,-57.73 -66.6,-58.76 -66.6,-59.79 -66.6,-60.82 -66.6,-61.85 -66.6,-62.88 -66.6,-63.91 -66.6,-64.94 -66.6,-65.97 -66.6,-67 -66.6,-67 -66.26,-67 -65.92,-67 -65.58,-67 -65.24,-67 -64.9,-67 -64.56,-67 -64.22,-67 -63.88,-67 -63.54,-67 -63.2))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 03 Dec 2014 00:00:00 GMT", "description": "Intellectual Merit: Recent geochemical, sequence stratigraphic, and integrated investigations of marine strata from several continental margins and ocean basins suggest that ephemeral ice sheets may have existed on Antarctica during parts of the Cretaceous and early Paleogene. However, atmospheric carbon dioxide estimates for this time are as much as four times modern levels. With such greenhouse conditions, the presence of Antarctic ice sheets would imply that our current understanding of Earth?s climate system, and specifically the interpreted thresholds of Antarctic glaciation and deglaciation should be reconsidered. The proposed research will compare the quantity and provenance of Cretaceous sediments in the Larsen basin of the eastern Antarctic Peninsula with the exhumation chronology and composition of potential sediment source terranes on the peninsula and in adjacent regions. New outcrop stratigraphic analyses with improvements in the age models from radioisotopic approaches will be integrated to determine the amount of detrital sediment fluxed to the Larsen basin between key chronostratigraphic surfaces. Microtextural analysis of quartz sand and silt grains will help determine whether the Larsen basin detrital sediment originated from glacial weathering. These preliminary results will test the viability of the proposed approach to assess the controversial Cretaceous Antarctic glaciation hypothesis. Broader impacts: The proposed work will partially support a PhD, a MSc, and three undergraduate students at the University of South Carolina. The PIs will publicize this work through volunteer speaking engagements and the development of videos and podcasts. They also commit to prompt publication of the results and timely submission of data to archives. The development/improvement of the Larsen basin age model will benefit ongoing research in paleobiology, paleoclimate and biogeography. Development of the glauconite K-Ar and Rb-Sr chronometers could be an important outcome beyond the direct scope of the proposed research.", "east": -56.7, "geometry": "POINT(-61.85 -64.9)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e LA-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MC-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e IRMS", "is_usap_dc": true, "keywords": "Not provided; Noble-Gas Mass Spectrometer; Antarctic Peninsula", "locations": "Antarctic Peninsula", "north": -63.2, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PROTEROZOIC; PHANEROZOIC \u003e PALEOZOIC; PHANEROZOIC \u003e MESOZOIC; PHANEROZOIC \u003e CENOZOIC; PHANEROZOIC \u003e MESOZOIC \u003e CRETACEOUS; PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE", "persons": "Barbeau, David; Hemming, Sidney R.; Barbeau, David Jr", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -66.6, "title": "Collaborative Research: EAGER: Evaluating the Larsen basin\u0027s suitability for testing the Cretaceous Glaciation Hypothesis", "uid": "p0000369", "west": -67.0}, {"awards": "0636705 Marchant, David; 0636731 Bender, Michael", "bounds_geometry": "POLYGON((160.48705 -77.84513,160.501913 -77.84513,160.516776 -77.84513,160.531639 -77.84513,160.546502 -77.84513,160.561365 -77.84513,160.576228 -77.84513,160.591091 -77.84513,160.605954 -77.84513,160.620817 -77.84513,160.63568 -77.84513,160.63568 -77.8515624,160.63568 -77.8579948,160.63568 -77.8644272,160.63568 -77.8708596,160.63568 -77.877292,160.63568 -77.8837244,160.63568 -77.8901568,160.63568 -77.8965892,160.63568 -77.9030216,160.63568 -77.909454,160.620817 -77.909454,160.605954 -77.909454,160.591091 -77.909454,160.576228 -77.909454,160.561365 -77.909454,160.546502 -77.909454,160.531639 -77.909454,160.516776 -77.909454,160.501913 -77.909454,160.48705 -77.909454,160.48705 -77.9030216,160.48705 -77.8965892,160.48705 -77.8901568,160.48705 -77.8837244,160.48705 -77.877292,160.48705 -77.8708596,160.48705 -77.8644272,160.48705 -77.8579948,160.48705 -77.8515624,160.48705 -77.84513))", "dataset_titles": "Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica; Measurements of Trapped Air from Mullins Valley, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "600069", "doi": "10.15784/600069", "keywords": "Antarctica; Dry Valleys; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope Record; Lake Vostok; Paleoclimate", "people": "Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600069"}, {"dataset_uid": "609597", "doi": "10.7265/N50R9MBM", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Dry Valleys; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Paleoclimate; Radar Interferometer", "people": "Bender, Michael; Yau, Audrey M.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of Trapped Air from Mullins Valley, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609597"}], "date_created": "Thu, 03 Feb 2011 00:00:00 GMT", "description": "This project studies ancient ice buried in the Dry Valleys of Antarctica. The ice, which may approach ten million years in age, will be dated using argon and uranium radioisotope techniques. High-risk work, if successful it will offer the first and perhaps only samples of the Earth\u0027s atmosphere from millions of years in the past. These samples could offer critically important tests of paleoclimate records and proxies, as well as a glimpse into the characteristics of a past world much like the predicted future, warmer Earth. The broader impacts are graduate student education, and potentially contributing to society\u0027s understanding of global climate change and sea level rise.", "east": 160.63568, "geometry": "POINT(160.561365 -77.877292)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Elemental Ratios; Oxygen Isotope; Not provided; Nitrogen Isotopes; LABORATORY; Argon Isotopes; FIELD INVESTIGATION", "locations": null, "north": -77.84513, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Bender, Michael; Yau, Audrey M.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.909454, "title": "Collaborative Research: Dating and Paleoenvironmental Studies on Ancient Ice in the Dry Valleys, Antarctica", "uid": "p0000039", "west": 160.48705}, {"awards": "0230348 Dunbar, Nelia; 0230021 Sowers, Todd; 0230316 White, James", "bounds_geometry": "POINT(135.1333 -76.05)", "dataset_titles": "Mount Moulton Isotopes and Other Ice Core Data", "datasets": [{"dataset_uid": "609640", "doi": "10.7265/N5FT8J0N", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Epica Dome C; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Mount Moulton; Paleoclimate; Talos Dome; Taylor Dome", "people": "Steig, Eric J.; White, James; Popp, Trevor", "repository": "USAP-DC", "science_program": null, "title": "Mount Moulton Isotopes and Other Ice Core Data", "url": "https://www.usap-dc.org/view/dataset/609640"}], "date_created": "Tue, 01 Aug 2006 00:00:00 GMT", "description": "The summit crater of Mt. Moulton, in West Antarctica, contains a 600-m thick horizontally-exposed section of ice with intercalated tephra layers from nearby Mt Berlin. Argon-40/Argon-39 dating of the thick, near-source tephra indicates that the age of the horizontal ice section ranges between 15,000 and 492,000 years. Thus, the Mt Moulton site offers an unparalleled repository of ancient West Antarctic snow and trapped air that can be used to investigate West Antarctic climate over much of the past 500,000 years. The planar nature and consistent dips of the tephra layers suggests that, although the ice section has thinned, it is otherwise undeformed. The Mt. Moulton site was visited during the 1999/2000 field season, at which time a horizontal ice core representing approximately 400 meters of ice was collected, ranging in age from 15,000 to older than 480,000 years. In addition to this horizontal core, samples of ice at a range of depths were collected in order to test the quality of the climate record in the ice. Forty tephra layers intercalated in the ice were also collected in order to provide chronology for the ice section. The results of this first effort are extremely encouraging. Based on the d?18 O of ice, for example, there is clearly a useable record of past climate at Mt. Moulton extending back beyond 140,000 years. There is work to do, however, to realize the full potential of this horizontal ice core. The elemental and isotopic composition of trapped gases suggest some contamination with modern air, for example. As gas cross-dating of ice cores is the current standard by which climate records are intercompared, we need to understand why and how the gas record is compromised before adding Moulton to our arsenal of ice core paleoclimate records. This award supports a collaborative effort between three institutions with following objectives: 1) to evaluate more thoroughly the integrity of the climatic record through shallow drilling of the blue ice area, as well as the snow field upslope from the blue ice; 2) to improve the radioisotopic dating of specific tephra layers; 3) to obtain baseline information about modern snowfall deposition, mean annual temperature, and wind pumping around the summit of Mt. Moulton; and 4) to study how firn densification differs when surface accumulation changes from net accumulation to net ablation.", "east": 135.1333, "geometry": "POINT(135.1333 -76.05)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES", "is_usap_dc": true, "keywords": "LABORATORY; Climate; Argon-40; 40Ar; Argon-39; FIELD SURVEYS; Chronology; Ice Core Gas Age; Gas Record; Ice Core; FIELD INVESTIGATION; Tephra; Mount Moulton; Not provided; Caldera; 39Ar; Stratigraphy; Ice Core Depth", "locations": "Mount Moulton", "north": -76.05, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "White, James; Popp, Trevor; Dunbar, Nelia; Sowers, Todd A.; Steig, Eric J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.05, "title": "Collaborative Research: Refining a 500-kry Climate Record From the Moulton Blue Ice Field in West Antarctica", "uid": "p0000755", "west": 135.1333}]

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