USAP-DC

{"dp_type": "Project", "free_text": "CARBON DIOXIDE"}

[{"awards": "1745078 Brook, Edward", "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": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ; Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation; Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "datasets": [{"dataset_uid": "601735", "doi": null, "keywords": "Antarctica; Cryosphere; Greenland; Methane; West Antarctic Ice Sheet", "people": "Edwards, Jon S.; Rosen, Julia; Martin, Kaden; Riddell-Young, Benjamin; Brook, Edward; Lee, James", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric methane across the Last Glacial Maximum and deglaciation from the GISP2, NEEM and WAIS Divide ice cores ", "url": "https://www.usap-dc.org/view/dataset/601735"}, {"dataset_uid": "601736", "doi": null, "keywords": "Antarctica; Cryosphere; Greenland; Methane; Paleoclimate; West Antarctic Ice Sheet", "people": "Edwards, Jon S.; M\u00fchl, Michaela; Schmitt, Jochen; Fischer, Hubertus; Riddell-Young, Benjamin; Blunier, Thomas; Brook, Edward; Rosen, Julia; Buizert, Christo; Martin, Kaden; Lee, James", "repository": "USAP-DC", "science_program": null, "title": "Atmospheric methane interpolar difference and four-box troposphere model output across the Last Glacial Maximum and Deglaciation", "url": "https://www.usap-dc.org/view/dataset/601736"}, {"dataset_uid": "601683", "doi": "10.15784/601683", "keywords": "Antarctica; Cryosphere; Methane; West Antarctic Ice Sheet", "people": "Riddell-Young, Benjamin", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Carbon-13 isotopic composition of atmospheric methane across Heinrich Stadials 1 and 5, and Dansgaard Oesgher Event 12, WAIS Divide Ice Core, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601683"}], "date_created": "Mon, 01 May 2023 00:00:00 GMT", "description": "This project will develop methods to measure the ratios of carbon-13 to carbon-12, and heavy to light hydrogen in methane in air trapped in ice cores. The ratios of the different forms of carbon and hydrogen are \"fingerprints\" of different sources of this gas in the past--for example wetlands in the tropics versus methane frozen in the sea floor. Once the analysis method is developed, the measurements will be used to examine why methane changed abruptly in the past, both during the last ice age, and during previous warm periods. The data will be used to understand how methane sources like wildfires, methane hydrates, and wetlands respond to climate change. This information is needed to understand future risks of large changes in methane in the atmosphere as Earth warms. \u003cbr/\u003e\u003cbr/\u003eThe project involves two tasks. First, the investigators will build and test a gas extraction system for methane isotopic measurements using continuous flow methods, with the goal of equaling or bettering the precision attained by the few other laboratories that make these measurements. The system will be interfaced with existing mass spectrometers at Oregon State University. The system consists of a vacuum chamber and sequence of traps, purification columns, and furnaces that separate methane from other gases and convert it to carbon dioxide or hydrogen for mass spectrometry. Second, the team will measure the isotopic composition of methane across large changes in concentration associated with two past interglacial periods and during abrupt methane changes of the last ice age. These measurements will be used to understand if the main reason for these concentration changes is climate-driven changes in emissions from wetlands, or whether other sources are involved, for example methane hydrates or wildfires.\u003cbr/\u003e\u003cbr/\u003eThis 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; TRACE GASES/TRACE SPECIES; METHANE", "locations": "Antarctic Ice Sheet", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Tracing Past Methane Variations with Stable Isotopes in Antarctic Ice Cores", "uid": "p0010416", "west": -180.0}, {"awards": "1543511 Stephens, Britton; 1543457 Munro, David", "bounds_geometry": "POLYGON((-73 -53,-71.2 -53,-69.4 -53,-67.6 -53,-65.8 -53,-64 -53,-62.2 -53,-60.4 -53,-58.6 -53,-56.8 -53,-55 -53,-55 -54.4,-55 -55.8,-55 -57.2,-55 -58.6,-55 -60,-55 -61.4,-55 -62.8,-55 -64.2,-55 -65.6,-55 -67,-56.8 -67,-58.6 -67,-60.4 -67,-62.2 -67,-64 -67,-65.8 -67,-67.6 -67,-69.4 -67,-71.2 -67,-73 -67,-73 -65.6,-73 -64.2,-73 -62.8,-73 -61.4,-73 -60,-73 -58.6,-73 -57.2,-73 -55.8,-73 -54.4,-73 -53))", "dataset_titles": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the Southern Ocean, Drake Passage and South Atlantic Ocean in 2018, processed by NOAA (NCEI Accession 0184338); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, Drake Passage, South Atlantic Ocean in 2022 (NCEI Accession 0276577); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Atlantic Ocean in 2021 (NCEI Accession 0246983); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean from 2019-02-16 to 2020-02-11 (NCEI Accession 0208838); Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean in 2020 (NCEI Accession 0225445); Underway measurements of pCO2 in the Surface Waters and the Atmosphere During the ARSV Laurence M. Gould 2017 Expeditions processed by NOAA (NCEI Accession 0170337)", "datasets": [{"dataset_uid": "200348", "doi": "https://doi.org/10.7289/v5tq5zt1", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Underway measurements of pCO2 in the Surface Waters and the Atmosphere During the ARSV Laurence M. Gould 2017 Expeditions processed by NOAA (NCEI Accession 0170337)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200353", "doi": "https://doi.org/10.25921/fq0a-7y11", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, Drake Passage, South Atlantic Ocean in 2022 (NCEI Accession 0276577)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200350", "doi": "https://doi.org/10.25921/3ysc-pm11", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean from 2019-02-16 to 2020-02-11 (NCEI Accession 0208838)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200351", "doi": "https://doi.org/10.25921/z0pk-pv81", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Pacific Ocean, Drake Passage and South Atlantic Ocean in 2020 (NCEI Accession 0225445)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200352", "doi": "https://doi.org/10.25921/f94g-zp40", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the the Southern Ocean, South Atlantic Ocean in 2021 (NCEI Accession 0246983)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}, {"dataset_uid": "200349", "doi": "https://doi.org/10.25921/b4jn-ef56", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Surface underway measurements of partial pressure of carbon dioxide (pCO2) during the Antarctic Research and Supply Vessel (ARSV) Laurence M. Gould expeditions in the Southern Ocean, Drake Passage and South Atlantic Ocean in 2018, processed by NOAA (NCEI Accession 0184338)", "url": "https://www.ncei.noaa.gov/access/ocean-carbon-acidification-data-system/oceans/VOS_Program/LM_gould.html"}], "date_created": "Wed, 22 Feb 2023 00:00:00 GMT", "description": "The Southern Ocean plays a key role in modulating the global carbon cycle, but the size and even the sign of the flux of carbon dioxide between the ocean and atmosphere in this region is still uncertain. This is in part due to the lack of measurements in this remote region of the world ocean. This project continues a multi-year time series of shipboard chemical measurements in the Drake Passage to detect changes in the ocean carbon cycle and to improve the understanding of mechanisms driving natural variability and long-term change in the Southern Ocean. More specifically, this project is a continuation of the collection of underway upper ocean measurements of the surface partial pressure of carbon dioxide during crossings of the Drake Passage by the Antarctic Research and Supply Vessel Laurence M. Gould. This project also includes collection and analysis of discrete samples relevant to ocean carbon cycle studies including macronutrient concentrations, total carbon dioxide concentrations, and the carbon isotopic composition of total carbon dioxide. The Drake Passage data are made readily available to the international science community and serve as both validation and constraints of remotely sensed observations and numerical coupled earth systems models.", "east": -55.0, "geometry": "POINT(-64 -60)", "instruments": null, "is_usap_dc": true, "keywords": "Drake Passage; NUTRIENTS; BIOGEOCHEMICAL CYCLES; DISSOLVED GASES; TRACE GASES/TRACE SPECIES", "locations": "Drake Passage", "north": -53.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Munro, David; Sweeney, Colm; Lovenduski, Nicole S; Stephens, Britton", "platforms": null, "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Investigating Biogeochemical Fluxes and Linkages To Climate Change With Multi-Scale Observations In The Drake Passage", "uid": "p0010407", "west": -73.0}, {"awards": "2147045 Learman, Deric", "bounds_geometry": "POLYGON((-180 -60,-168 -60,-156 -60,-144 -60,-132 -60,-120 -60,-108 -60,-96 -60,-84 -60,-72 -60,-60 -60,-60 -62,-60 -64,-60 -66,-60 -68,-60 -70,-60 -72,-60 -74,-60 -76,-60 -78,-60 -80,-72 -80,-84 -80,-96 -80,-108 -80,-120 -80,-132 -80,-144 -80,-156 -80,-168 -80,180 -80,171 -80,162 -80,153 -80,144 -80,135 -80,126 -80,117 -80,108 -80,99 -80,90 -80,90 -78,90 -76,90 -74,90 -72,90 -70,90 -68,90 -66,90 -64,90 -62,90 -60,99 -60,108 -60,117 -60,126 -60,135 -60,144 -60,153 -60,162 -60,171 -60,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 30 Aug 2022 00:00:00 GMT", "description": "Microbes in Antarctic surface marine sediments have an important role in degrading organic matter and releasing nutrients to the ocean. Organic matter degradation is at the center of the carbon cycle in the ocean, providing valuable information on nutrient recycling, food availability to animals and carbon dioxide release to the atmosphere. The functionality of these microbes has been inferred by their genomics, however these methods only address the possible function, not their actual rates. In this project the PIs plan to combine genomics methods with cellular estimates of enzyme abundance and activity as a way to determine the rates of carbon degradation. This project aims to sample in several regions of Antarctica to provide a large-scale picture of the processes under study and understand the importance of microbial community composition and environmental factors, such as primary productivity, have on microbial activity. The proposed work will combine research tools such as metagenomics, meta-transcriptomics, and metabolomics coupled with chemical data and enzyme assays to establish degradation of organic matter in Antarctic sediments. This project benefits NSFs goals of understanding the adaptation of Antarctic organisms to the cold and isolated environment, critical to predict effects of climate change to polar organisms, as well as contribute to our knowledge of how Antarctic organisms have adapted to this environment. Society will benefit from this project by education of 2 graduate students, undergraduates and K-12 students as well as increase public literacy through short videos production shared in YouTube.\r\n\r\nThe PIs propose to advance understanding of polar microbial community function, by measuring enzyme and gene function of complex organic matter degradation in several ocean regions, providing a circum-Antarctic description of sediment processes. Two hypotheses are proposed. The first hypothesis states that many genes for the degradation of complex organic matter will be shared in sediments throughout a sampling transect and that where variations in gene content occur, it will reflect differences in the quantity and quality of organic matter, not regional variability. The second hypothesis states that a fraction of gene transcripts for organic matter degradation will not result in measurable enzyme activity due to post-translational modification or rapid degradation of the enzymes. The PIs will analyze sediment cores already collected in a 2020 cruise to the western Antarctic Peninsula with the additional request of participating in a cruise in 2023 to East Antarctica. The PIs will analyze sediments for metagenomics, meta-transcriptomics, and metabolomics coupled with geochemical data and enzyme assays to establish microbial degradation of complex organic matter in Antarctic sediments. Organic carbon concentrations and content in sediments will be measured with \u03b413C, \u03b415N, TOC porewater fluorescence in bulk organic carbon. Combined with determination of geographical variability as well as dependence on carbon sources, results from this study could provide the basis for new hypotheses on how climate variability, with increased water temperature, affects geochemistry in the Southern Ocean.", "east": 90.0, "geometry": "POINT(-165 -70)", "instruments": null, "is_usap_dc": true, "keywords": "BENTHIC; ECOSYSTEM FUNCTIONS; Weddell Sea; Antarctic Peninsula; SEDIMENT CHEMISTRY; R/V NBP", "locations": "Antarctic Peninsula; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Learman, Deric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repositories": null, "science_programs": null, "south": -80.0, "title": "Collaborative Research: ANT LIA: Connecting Metagenome Potential to Microbial Function: Investigating Microbial Degradation of Complex Organic Matter Antarctic Benthic Sediments", "uid": "p0010373", "west": -60.0}, {"awards": "2212904 Herbert, Lisa", "bounds_geometry": "POLYGON((-120 -71,-118 -71,-116 -71,-114 -71,-112 -71,-110 -71,-108 -71,-106 -71,-104 -71,-102 -71,-100 -71,-100 -71.4,-100 -71.8,-100 -72.2,-100 -72.6,-100 -73,-100 -73.4,-100 -73.8,-100 -74.2,-100 -74.6,-100 -75,-102 -75,-104 -75,-106 -75,-108 -75,-110 -75,-112 -75,-114 -75,-116 -75,-118 -75,-120 -75,-120 -74.6,-120 -74.2,-120 -73.8,-120 -73.4,-120 -73,-120 -72.6,-120 -72.2,-120 -71.8,-120 -71.4,-120 -71))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "The Amundsen Sea, near the fastest melting Antarctic glaciers, hosts one of the most productive polar ecosystems in the world. Phytoplankton serve as the base of the food chain, and their growth also removes carbon dioxide from the atmosphere. Phytoplankton growth is fertilized in this area by nutrient iron (Fe), which is only present at low concentrations in seawater. Prior studies have shown the seabed sediments may provide Fe to the Amundsen Sea ecosystem. However, sediment sources of Fe have never been studied here directly. This project fills this gap by analyzing sediments from the Amundsen Sea and investigating whether sediment Fe fertilizes plankton growth. The results will help scientists understand the basic ecosystem drivers and predict the effects of climate change on this vibrant, vulnerable region. This project also emphasizes inclusivity and openness to the public. The researchers will establish a mentoring network for diverse polar scientists through the Polar Impact Network and communicate their results to the public through CryoConnect.org. \r\n\r\nThis project leverages samples already collected from the Amundsen Sea (NBP22-02) to investigate sediment Fe cycling and fluxes. The broad questions driving this research are 1) does benthic Fe fertilize Antarctic coastal primary productivity, and 2) what are the feedbacks between benthic Fe release and carbon cycling in the coastal Antarctic? To answer these questions, the researchers will analyze pore water Fe content and speciation and calculate fluxes of Fe across the sediment-water interface. These results will be compared to sediment characteristics (e.g., organic carbon content, reactive Fe content, proximity to glacial sources) to identify controls on benthic Fe release. This research dovetails with and expands on the science goals of the \u201cAccelerating Thwaites Ecosystem Impacts for the Southern Ocean\u201d (ARTEMIS) project through which the field samples were collected. In turn, the findings of ARTEMIS regarding modeled and observed trace metal dynamics, surface water productivity, and carbon cycling will inform the conclusions of this project, allowing insight into the impact of benthic Fe in the whole system. This project represents a unique opportunity for combined study of the water column and sediment biogeochemistry which will be of great value to the marine biogeochemistry community and will inform future sediment-ocean studies in polar oceanography and beyond. \r\n", "east": -100.0, "geometry": "POINT(-110 -73)", "instruments": null, "is_usap_dc": true, "keywords": "TRACE ELEMENTS; Amundsen Sea Embayment; SEDIMENT CHEMISTRY", "locations": "Amundsen Sea Embayment", "north": -71.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": null, "persons": "Herbert, Lisa", "platforms": null, "repositories": null, "science_programs": null, "south": -75.0, "title": "OPP-PRF: Benthic Iron Fluxes and Cycling in the Amundsen Sea", "uid": "p0010362", "west": -120.0}, {"awards": "1643664 Severinghaus, Jeffrey; 1643669 Petrenko, Vasilii; 1643716 Buizert, Christo", "bounds_geometry": "POLYGON((112 -66,112.2 -66,112.4 -66,112.6 -66,112.8 -66,113 -66,113.2 -66,113.4 -66,113.6 -66,113.8 -66,114 -66,114 -66.1,114 -66.2,114 -66.3,114 -66.4,114 -66.5,114 -66.6,114 -66.7,114 -66.8,114 -66.9,114 -67,113.8 -67,113.6 -67,113.4 -67,113.2 -67,113 -67,112.8 -67,112.6 -67,112.4 -67,112.2 -67,112 -67,112 -66.9,112 -66.8,112 -66.7,112 -66.6,112 -66.5,112 -66.4,112 -66.3,112 -66.2,112 -66.1,112 -66))", "dataset_titles": "Concentration and isotopic composition of atmospheric N2O over the last century; Law Dome DE08-OH firn air 15N, O2/N2, Ar/N2, 18O of O2; Law Dome DE08-OH site noble gases in ice: testing the 86Krexcess proxy", "datasets": [{"dataset_uid": "601597", "doi": "10.15784/601597", "keywords": "Antarctica; Cryosphere; ice cores; Law Dome; noble gases", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Law Dome DE08-OH site noble gases in ice: testing the 86Krexcess proxy", "url": "https://www.usap-dc.org/view/dataset/601597"}, {"dataset_uid": "601693", "doi": "10.15784/601693", "keywords": "Antarctic; Antarctica; Anthropogenic Emission; Atmosphere; Cryosphere; Cryosphere; Greenhouse Gas; Greenland; Ice Core Data; Nitrification and Denitrification Processes; Nitrous Oxide; Site-specific 15N isotopomer; Styx Glacier", "people": "Etheridge, David; Ahn, Jinho ; Joong Kim, Seong; Yoshida, Naohiro ; Langenfelds, Ray L ; Buizert, Christo ; Toyoda, Sakae ; Ghosh, Sambit", "repository": "USAP-DC", "science_program": null, "title": "Concentration and isotopic composition of atmospheric N2O over the last century", "url": "https://www.usap-dc.org/view/dataset/601693"}, {"dataset_uid": "601598", "doi": "10.15784/601598", "keywords": "Antarctica; Cryosphere; Firn; firn densification; Gravitational Settling; Inert Gases; Law Dome", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Law Dome DE08-OH firn air 15N, O2/N2, Ar/N2, 18O of O2", "url": "https://www.usap-dc.org/view/dataset/601598"}], "date_created": "Fri, 17 Jun 2022 00:00:00 GMT", "description": "Hydroxyl radicals are responsible for removal of most atmospheric trace gases, including pollutants and important greenhouse gases. They have been called the \"detergent of the atmosphere\". Changes in hydroxyl radical concentration in response to large changes in reactive trace gas emissions, which may happen in the future, are uncertain. This project aims to provide the first estimates of the variability of atmospheric hydroxyl radicals since about 1880 AD when anthropogenic emissions of reactive trace gases were minimal. This will improve understanding of their stability in response to large changes in emissions. The project will also investigate whether ice cores record past changes in Southern Hemisphere westerly winds. These winds are a key component of the global climate system, and have an important influence on ocean circulation and possibly on atmospheric carbon dioxide concentrations. The project team will include three early career scientists, a postdoctoral researcher, and graduate and undergraduate students, working in collaboration with senior scientists and Australian collaborators. \u003cbr/\u003e \u003cbr/\u003eFirn air and shallow ice to a depth of about 233 m will be sampled at the Law Dome high-accumulation coastal site in East Antarctica. Trapped air will be extracted from the ice cores on site immediately after drilling. Carbon-14 of carbon monoxide (14CO) will be analyzed in firn and ice-core air samples. Corrections will be made for the in situ cosmogenic 14CO component in the ice, allowing for the atmospheric 14CO history to be reconstructed. This 14CO history will be interpreted with the aid of a chemistry-transport model to place the first observational constraints on the variability of Southern Hemisphere hydroxyl radical concentration after about 1880 AD. An additional component of the project will analyze Krypton-86 in the firn-air and ice-core samples. These measurements will explore whether ice-core Krypton-86 acts as a proxy for barometric pressure variability, and whether this proxy can be used in Antarctic ice cores to infer past movement of the Southern Hemisphere westerly winds.\u003cbr/\u003e\u003cbr/\u003eThis 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": 114.0, "geometry": "POINT(113 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; TRACE GASES/TRACE SPECIES; Law Dome; USAP-DC; LABORATORY; ICE CORE AIR BUBBLES; AMD/US; USA/NSF", "locations": "Law Dome", "north": -66.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Petrenko, Vasilii; Murray, Lee T; Buizert, Christo; Petrenko, Vasilii; Murray, Lee T", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Research: Reconstructing Carbon-14 of Atmospheric Carbon Monoxide from Law Dome, Antarctica to Constrain Long-Term Hydroxyl Radical Variability", "uid": "p0010341", "west": 112.0}, {"awards": "1951090 Stukel, Michael", "bounds_geometry": "POLYGON((-80 -63,-78.2 -63,-76.4 -63,-74.6 -63,-72.8 -63,-71 -63,-69.2 -63,-67.4 -63,-65.6 -63,-63.8 -63,-62 -63,-62 -63.7,-62 -64.4,-62 -65.1,-62 -65.8,-62 -66.5,-62 -67.2,-62 -67.9,-62 -68.6,-62 -69.3,-62 -70,-63.8 -70,-65.6 -70,-67.4 -70,-69.2 -70,-71 -70,-72.8 -70,-74.6 -70,-76.4 -70,-78.2 -70,-80 -70,-80 -69.3,-80 -68.6,-80 -67.9,-80 -67.2,-80 -66.5,-80 -65.8,-80 -65.1,-80 -64.4,-80 -63.7,-80 -63))", "dataset_titles": "BCO-DMO Project Page", "datasets": [{"dataset_uid": "200294", "doi": null, "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "BCO-DMO Project Page", "url": "https://www.bco-dmo.org/project/838048"}], "date_created": "Fri, 03 Jun 2022 00:00:00 GMT", "description": "Algae in the surface ocean convert carbon dioxide into organic carbon through photosynthesis. The biological carbon pump transports this organic carbon from the atmosphere to the deep ocean where it can be stored for tens to hundreds of years. Annually, the amount transported is similar to that humans are currently emitting by burning fossil fuels. However, at present we cannot predict how this important process will change with a warming ocean. These investigators plan to develop a 15+ year time-series of vertical carbon transfer for the Western Antarctic Peninsula; a highly productive Antarctic ecosystem. This region is also rapid transition to warmer temperatures leading to reduced sea ice coverage. This work will help researchers better understand how the carbon cycle in the Western Antarctic Peninsula will respond to climate change. The researchers will develop the first large-scale time-series of carbon flux anywhere in the ocean. This research will also support the education and training of a graduate student and support the integration of concepts in Antarctic research into two undergraduate courses designed for non-science majors and advanced earth science students. The researchers will also develop educational modules for introducing elementary and middle-school age students to important concepts such as gross and net primary productivity, feedbacks in the marine and atmospheric systems, and the differences between correlation and causation. Results from this proposal will also be incorporated into a children?s book, ?Plankton do the Strangest Things?, that is targeted at 5-7 year olds and is designed to introduce them to the incredible diversity and fascinating adaptations of microscopic marine organisms.\u003cbr/\u003e\u003cbr/\u003e This research seeks to leverage 6 years (2015-2020) of 234Th samples collected on Palmer LTER program, 5 years of prior measurements (2009-2010, 2012-2014), and upcoming cruises (2021-2023) to develop a time-series of summertime particle flux in the WAP that stretches for 15 years. The 238U-234Th disequilibrium approach utilizes changes in the activity of the particle-active radio-isotope 234Th relative to its parent nuclide 238U to quantify the flux of sinking carbon out of the surface ocean (over a time-scale of ~one month). This proposal will fund 234Th analyses from nine years? worth of cruises (2015-2023) and extensive analyses designed to investigate the processes driving inter-annual variability in the BCP. These include: 1) physical modeling to quantify the importance of advection and diffusion in the 234Th budget, 2) time-series analyses of particle flux, and 3) statistical modeling of the relationships between particle flux and multiple presumed drivers (biological, chemical, physical, and climate indices) measured by collaborators in the Palmer LTER program. This multi-faceted approach is critical for linking the measurements to models and for predicting responses to climate change. It will also test the hypothesis that export flux is decreasing in the northern WAP, increasing in the southern WAP, and increasing when integrated over the entire region as a result of earlier sea ice retreat and a larger ice-free zone. The project will also investigate relationships between carbon export and multiple potentially controlling factors including: primary productivity, algal biomass and taxonomic composition, biological oxygen saturation, zooplankton biomass and taxonomic composition, bacterial production, temperature, wintertime sea ice extent, date of sea ice retreat, and climate modes.\u003cbr/\u003e\u003cbr/\u003eThis 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": -62.0, "geometry": "POINT(-71 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; AMD/US; FIELD INVESTIGATION; Palmer Station; USAP-DC; BIOGEOCHEMICAL CYCLES; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Stukel, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -70.0, "title": "Quantifying Processes Driving Interannual Variability in the Biological Carbon Pump in the Western Antarctic Peninsula", "uid": "p0010332", "west": -80.0}, {"awards": "2019719 Brook, Edward J.", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report; Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "datasets": [{"dataset_uid": "601697", "doi": "10.15784/601697", "keywords": "Allan Hills; Antarctica; ApRES; Cryosphere; Ice Core; Ice Penetrating Radar; Temperature Profiles", "people": "Brook, Edward; Conway, Howard", "repository": "USAP-DC", "science_program": "COLDEX", "title": "2022-23 Allan Hills Intermediate Ice Core Site Selection Field Report", "url": "https://www.usap-dc.org/view/dataset/601697"}, {"dataset_uid": "601659", "doi": "10.15784/601659", "keywords": "Antarctica; Continuous Flow; Cryosphere; Glaciology; Greenland; Ice Core Data; Laser Spectroscopy; Oxygen Isotopes; Triple Oxygen Isotopes", "people": "Davidge, Lindsey", "repository": "USAP-DC", "science_program": "Hercules Dome Ice Core", "title": "Replicate O-17-excess by continuous flow laser spectroscopy for an ice core section at Summit, Greenland", "url": "https://www.usap-dc.org/view/dataset/601659"}], "date_created": "Sat, 21 May 2022 00:00:00 GMT", "description": "Cores drilled through the Antarctic ice sheet provide a remarkable window on the evolution of Earth\u2019s climate and unique samples of the ancient atmosphere. The clear link between greenhouse gases and climate revealed by ice cores underpins much of the scientific understanding of climate change. Unfortunately, the existing data do not extend far enough back in time to reveal key features of climates warmer than today. COLDEX, the Center for Oldest Ice Exploration, will solve this problem by exploring Antarctica for sites to collect the oldest possible record of past climate recorded in the ice sheet. COLDEX will provide critical information for understanding how Earth\u2019s near-future climate may evolve and why climate varies over geologic time. New technologies will be developed for exploration and analysis that will have a long legacy for future research. An archive of old ice will stimulate new research for the next generations of polar scientists. COLDEX programs will galvanize that next generation of polar researchers, bring new results to other scientific disciplines and the public, and help to create a more inclusive and diverse scientific community.\r\n\r\nKnowledge of Earth\u2019s climate history is grounded in the geologic record. This knowledge is gained by measuring chemical, biological and physical properties of geologic materials that reflect elements of climate. Ice cores retrieved from polar ice sheets play a central role in this science and provide the best evidence for a strong link between atmospheric carbon dioxide and climate on geologic timescales. The goal of COLDEX is to extend the ice-core record of past climate to at least 1.5 million years by drilling and analyzing a continuous ice core in East Antarctica, and to much older times using discontinuous ice sections at the base and margin of the ice sheet. COLDEX will develop and deploy novel radar and melt-probe tools to rapidly explore the ice, use ice-sheet models to constrain where old ice is preserved, conduct ice coring, develop new analytical systems, and produce novel paleoclimate records from locations across East Antarctica. The search for Earth\u2019s oldest ice also provides a compelling narrative for disseminating information about past and future climate change and polar science to students, teachers, the media, policy makers and the public. COLDEX will engage and incorporate these groups through targeted professional development workshops, undergraduate research experiences, a comprehensive communication program, annual scientific meetings, scholarships, and broad collaboration nationally and internationally. COLDEX will provide a focal point for efforts to increase diversity in polar science by providing field, laboratory, mentoring and networking experiences for students and early career scientists from groups underrepresented in STEM, and by continuous engagement of the entire COLDEX community in developing a more inclusive scientific culture.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; COLDEX; AMD; Antarctica; USAP-DC; FIELD SURVEYS; ICE DEPTH/THICKNESS; AMD/US", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Neff, P.; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -90.0, "title": "Center for Oldest Ice Exploration", "uid": "p0010321", "west": -180.0}, {"awards": "2053726 Hofmann, Gretchen", "bounds_geometry": "POLYGON((163 -77,163.4 -77,163.8 -77,164.2 -77,164.6 -77,165 -77,165.4 -77,165.8 -77,166.2 -77,166.6 -77,167 -77,167 -77.1,167 -77.2,167 -77.3,167 -77.4,167 -77.5,167 -77.6,167 -77.7,167 -77.8,167 -77.9,167 -78,166.6 -78,166.2 -78,165.8 -78,165.4 -78,165 -78,164.6 -78,164.2 -78,163.8 -78,163.4 -78,163 -78,163 -77.9,163 -77.8,163 -77.7,163 -77.6,163 -77.5,163 -77.4,163 -77.3,163 -77.2,163 -77.1,163 -77))", "dataset_titles": "Analyses combining ATAC-seq, RRBS, and RNA-seq data for purple urchins", "datasets": [{"dataset_uid": "200288", "doi": "", "keywords": null, "people": null, "repository": "GitHub", "science_program": null, "title": "Analyses combining ATAC-seq, RRBS, and RNA-seq data for purple urchins", "url": "https://github.com/snbogan/Sp_RRBS_ATAC"}], "date_created": "Thu, 14 Apr 2022 00:00:00 GMT", "description": "Part 1: Non-technical description:\r\n\tWith support from the Office of Polar Programs, this project will evaluate how an important part of the food web in the coastal ocean of Antarctica will respond to climate change. The focal study organism in the plankton is a shelled mollusk, the Antarctic pteropod, Limacina helicina antarctica, a Southern Ocean organism that this known to respond to climate driven changes in ocean acidification and ocean warming. Ocean acidification, the lowering of ocean pH via the absorption of atmospheric carbon dioxide in the surface of the ocean, is a change in the ocean that is expected to cross deleterious thresholds of pH within decades. This study will improve understanding of how pteropods will respond, which will provide insight into predicting the resilience of the Antarctic marine ecosystem during future changes, one of the planets last marine wildernesses. The project will use tools of molecular biology to examine specifically how gene expression is modulated in the pteropods, and further, how the changes and regulation of genes act to resist the stress of low pH and high temperature. In addition, this project supports the training of Ph.D. graduate students and advances the goal of inclusive excellence in STEM and in marine sciences, in particular. The students involved in this project are from groups traditionally under-represented in marine science including first-generation college students. Overall, the project contributes to the development of the U.S. work force and contributes to diversity and inclusive excellence in the geosciences.\r\n\r\nPart 2: Technical description: \r\nThe overarching goal of this project is to investigate the molecular response of the Antarctic thecosome pteropod, Limacina helicina antarctica to ocean acidification (OA) and ocean warming. The project will investigate changes in the epigenome of juvenile L. h. antarctica, by assessing the dynamics of DNA methylation in response to three scenarios of environmental conditions that were simulated in laboratory mesocosm CO2 experiments: (1) present-day pCO2 conditions for summer and winter, (2) future ocean acidification expected within 10-15 years, and (3) a multiple stressor experiment to investigate synergistic interaction of OA and high temperature stress. Recent lab-based mesocosm experiment research showed significant changes in the dynamics of global DNA methylation in the pteropod genome, along with variation in gene expression in response to abiotic changes. Thus, it is clear that juvenile L. h. antarctica are capable of mounting a substantial epigenetic response to ocean acidification. However, it is not known how DNA methylation, as an epigenetic process, is modulating changes in the transcriptome. In order to address this gap in the epigenetic knowledge regarding pteropods, the project will use next-generation sequencing approaches (e.g., RNA sequencing and reduced representation bisulfite sequencing) to integrate changes in methylation status with changes in gene expression in juvenile pteropods. Overall, this investigation is an important step in exploring environmental transcriptomics and phenotypic plasticity of an ecologically important member of Southern Ocean macrozoooplankton in response to anthropogenic climate change.\r\n\r\nThis 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": 167.0, "geometry": "POINT(165 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; McMurdo Sound; FIELD INVESTIGATION; AMD/US; USA/NSF; AMD; MARINE ECOSYSTEMS; ANIMALS/INVERTEBRATES", "locations": "McMurdo Sound", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hofmann, Gretchen", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "GitHub", "repositories": "GitHub", "science_programs": null, "south": -78.0, "title": "The Role of the Epigenetic Mechanism, DNA Methylation, in the Tolerance and Resistance of Antarctic Pteropods to Ocean Acidification and Warming", "uid": "p0010313", "west": 163.0}, {"awards": "2149500 Chambers, Don", "bounds_geometry": "POLYGON((-180 -30,-144 -30,-108 -30,-72 -30,-36 -30,0 -30,36 -30,72 -30,108 -30,144 -30,180 -30,180 -36,180 -42,180 -48,180 -54,180 -60,180 -66,180 -72,180 -78,180 -84,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -84,-180 -78,-180 -72,-180 -66,-180 -60,-180 -54,-180 -48,-180 -42,-180 -36,-180 -30))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 14 Mar 2022 00:00:00 GMT", "description": "The Southern Ocean accounts for ~40% of the total ocean uptake of anthropogenic CO2 despite covering only 20% of the global ocean surface, and is particularly rich in long-lived eddies. These eddies, or large ocean whirlpools which can be observed from space, can alter air-sea fluxes of CO2 in ways that are not yet fully understood. New observations from autonomous platforms measuring ocean carbon content suggest that there is significant heterogeneity in ocean carbon fluxes which can be linked to these dynamic eddy features. Due to computational and time limitations, ocean eddies are not explicitly represented in most climate models, limiting our ability to understand the role eddies play in the ocean carbon cycle. This work will explore the impact of eddies on ocean carbon content and air-sea CO2 fluxes in the Southern Ocean using both model- and observation-based strategies and the findings will improve our understanding of the ocean\u2019s role in the carbon cycle and in global climate. While this work will primarily be focused on the Southern Ocean, the results will be globally applicable. The researchers will also broaden interest in physical and chemical oceanography among middle school-age girls in the University of South Florida\u2019s Oceanography Camp for Girls by augmenting existing lessons with computational methods in oceanography. \r\n\r\nThis project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a \u201cModel STEM Program for Women and Girls\u201d focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; PH; BIOGEOCHEMICAL CYCLES; AMD; OCEAN CHEMISTRY; OCEAN MIXED LAYER; USA/NSF; NITROGEN; OCEAN CURRENTS; SALINITY/DENSITY; USAP-DC; OCEAN TEMPERATURE; MODELS; CHLOROPHYLL; DISSOLVED GASES; NUTRIENTS; AMD/US", "locations": "Southern Ocean", "north": -30.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Williams, Nancy; Chambers, Don; Tamsitt, Veronica", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Diagnosing the Role of Ocean Eddies in Carbon Cycling from a High-resolution Data Assimilating Ocean Biogeochemical Model", "uid": "p0010309", "west": -180.0}, {"awards": "2149501 Mazloff, Matthew", "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": "Fri, 04 Mar 2022 00:00:00 GMT", "description": "This project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a \u201cModel STEM Program for Women and Girls\u201d focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; AMD; USA/NSF; AMD/US; USAP-DC; MODELS; BIOGEOCHEMICAL CYCLES", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Mazloff, Matthew", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Diagnosing the role of ocean eddies in carbon cycling from a high- resolution data assimilating ocean biogeochemical model", "uid": "p0010304", "west": -180.0}, {"awards": "1643394 Buizert, Christo", "bounds_geometry": "POLYGON((-180 -65,-144 -65,-108 -65,-72 -65,-36 -65,0 -65,36 -65,72 -65,108 -65,144 -65,180 -65,180 -67.5,180 -70,180 -72.5,180 -75,180 -77.5,180 -80,180 -82.5,180 -85,180 -87.5,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.5,-180 -85,-180 -82.5,-180 -80,-180 -77.5,-180 -75,-180 -72.5,-180 -70,-180 -67.5,-180 -65))", "dataset_titles": "Antarctica 40,000 Year Temperature and Elevation Reconstructions; GISP2 and WAIS Divide Ice Cores 60,000 Year Surface Temperature Reconstructions; WAIS Divide 67-6ka nssS Data and EDML, EDC and TALDICE Volcanic Tie Points", "datasets": [{"dataset_uid": "200257", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "GISP2 and WAIS Divide Ice Cores 60,000 Year Surface Temperature Reconstructions", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/34133"}, {"dataset_uid": "200256", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "WAIS Divide 67-6ka nssS Data and EDML, EDC and TALDICE Volcanic Tie Points", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/24530"}, {"dataset_uid": "200255", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Antarctica 40,000 Year Temperature and Elevation Reconstructions", "url": "https://www.ncei.noaa.gov/access/paleo-search/study/32632"}], "date_created": "Wed, 10 Nov 2021 00:00:00 GMT", "description": "This award supports a project to use ice cores to study teleconnections between the northern hemisphere, tropics, and Antarctica during very abrupt climate events that occurred during the last ice age (from 70,000 to 11,000 years ago). The observations can be used to test scientific theories about the role of the westerly winds on atmospheric carbon dioxide. In a warming world, snow fall in Antarctica is expected to increase, which can reduce the Antarctic contribution to sea level rise, all else being equal. The study will investigate how snow fall changed in the past in response to changes in temperature and atmospheric circulation, which can help improve projections of future sea level rise. Antarctica is important for the future evolution of our planet in several ways; it has the largest inventory of land-based ice, equivalent to about 58 m of global sea level and currently contributes about 0.3 mm per year to global sea level rise, which is expected to increase in the future due to global warming. The oceans surrounding Antarctica help regulate the uptake of human-produced carbon dioxide. Shifts in the position and strength of the southern hemisphere westerly winds could change the amount of carbon dioxide that is absorbed by the ocean, which will influence the rate of global warming. The climate and winds near and over Antarctica are linked to the rest of our planet via so-called climatic teleconnections. This means that climate changes in remote places can influence the climate of Antarctica. Understanding how these climatic teleconnections work in both the ocean and atmosphere is an important goal of climate research. The funds will further contribute towards training of a postdoctoral researcher and an early-career researcher; outreach to public schools; and the communication of research findings to the general public via the media, local events, and a series of Wikipedia articles.\r\n\r\nThe project will help to fully characterize the timing and spatial pattern of millennial-scale Antarctic climate change during the deglaciation and Dansgaard-Oeschger (DO) cycles using multiple synchronized Antarctic ice cores. The phasing of Antarctic climate change relative to Greenland DO events can distinguish between fast atmospheric teleconnections on sub-decadal timescales, and slow oceanic ones on centennial time scales. Preliminary work suggests that the spatial pattern of Antarctic change can fingerprint specific changes to the atmospheric circulation; in particular, the proposed work will clarify past movements of the Southern Hemisphere westerly winds during the DO cycle, which have been hypothesized. The project will help resolve a discrepancy between two previous seminal studies on the precise timing of interhemispheric coupling between ice cores in both hemispheres. The study will further provide state-of-the-art, internally-consistent ice core chronologies for all US Antarctic ice cores, as well as stratigraphic ties that can be used to integrate them into a next-generation Antarctic-wide ice core chronological framework. Combined with ice-flow modeling, these chronologies will be used for a continent-wide study of the relationship between ice sheet accumulation and temperature during the last deglaciation.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; ISOTOPES; Antarctica; USA/NSF; AMD; ICE CORE RECORDS; USAP-DC; VOLCANIC DEPOSITS; MODELS", "locations": "Antarctica", "north": -65.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Buizert, Christo; Wettstein, Justin", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -90.0, "title": "Collaborative Research: The Timing and Spatial Expression of the Bipolar Seesaw in Antarctica from Synchronized Ice Cores", "uid": "p0010279", "west": -180.0}, {"awards": "2046800 Thurber, Andrew", "bounds_geometry": "POLYGON((162 -77,162.6 -77,163.2 -77,163.8 -77,164.4 -77,165 -77,165.6 -77,166.2 -77,166.8 -77,167.4 -77,168 -77,168 -77.1,168 -77.2,168 -77.3,168 -77.4,168 -77.5,168 -77.6,168 -77.7,168 -77.8,168 -77.9,168 -78,167.4 -78,166.8 -78,166.2 -78,165.6 -78,165 -78,164.4 -78,163.8 -78,163.2 -78,162.6 -78,162 -78,162 -77.9,162 -77.8,162 -77.7,162 -77.6,162 -77.5,162 -77.4,162 -77.3,162 -77.2,162 -77.1,162 -77))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 21 Aug 2021 00:00:00 GMT", "description": "Due to persistent cold temperatures, geographical isolation, and resulting evolutionary distinctness of Southern Ocean fauna, the study of Antarctic reducing habitats has the potential to fundamentally alter our understanding of the biologic processes that inhibit greenhouse gas emissions from our oceans. Marine methane, a greenhouse gas 25x as potent as carbon dioxide for warming our atmosphere, is currently a minor component of atmospheric forcing due to the microbial oxidation of methane within the oceans. Based on studies of persistent deep-sea seeps at mid- and northern latitudes we have learned that bacteria and archaea create a \u2018sediment filter\u2019 that oxidizes methane prior to its release. As increasing global temperatures have and will continue to alter the rate and variance of methane release, the ability of the microbial filter to respond to fluctuations in methane cycles is a critical yet unexplored avenue of research. Antarctica contains vast reservoirs of methane, equivalent to all of the permafrost in the Arctic, and yet we know almost nothing about the fauna that may mitigate its release, as until recently, we had not discovered an active methane seep.\r\n\r\nIn 2012, a methane seep was discovered in the Ross Sea, Antarctica that formed in 2011 providing the first opportunity to study an active Antarctic methane-fueled habitat and simultaneously the impact of microbial succession on the oxidation of methane, a critical ecosystem service. Previous work has shown that after 5 years of seepage, the community was at an early stage of succession and unable to mitigate the release of methane from the seafloor. In addition, additional areas of seepage had begun nearby. This research aims to quantify the community trajectory of these seeps in relation to their role in the Antarctic Ecosystem, from greenhouse gas mitigation through supporting the food web. Through the application of genomic and transcriptomic approaches, taxa involved in methane cycling and genes activated by the addition of methane will be identified and contrasted with those from other geographical locations. These comparisons will elucidate how taxa have evolved and adapted to the polar environment.\r\n\r\nThis research uses a \u2018genome to ecosystem\u2019 approach to advance our understanding of organismal and systems ecology in Antarctica. By quantifying the trajectory of community succession following the onset of methane emission, the research will decipher temporal shifts in biodiversity/ecosystem function relationships. Phylogenomic approaches focusing on taxa involved in methane cycling will advance the burgeoning field of microbial biogeography on a continent where earth\u2019s history may have had a profound yet unquantified impact on microbial evolution. Further, the research will empirically quantify the role of chemosynthesis as a form of export production from seeps and in non-seep habitats in the nearshore Ross Sea benthos, informing our understanding of Antarctic carbon cycling.\r\n", "east": 168.0, "geometry": "POINT(165 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; USA/NSF; USAP-DC; BACTERIA/ARCHAEA; McMurdo Sound; BENTHIC; FIELD SURVEYS; AMD/US; ECOSYSTEM FUNCTIONS", "locations": "McMurdo Sound", "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Thurber, Andrew", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -78.0, "title": "CAREER: Ecosystem Impacts of Microbial Succession and Production at Antarctic Methane Seeps", "uid": "p0010250", "west": 162.0}, {"awards": "1848887 McClintock, James", "bounds_geometry": "POINT(-64.0527 -64.77423)", "dataset_titles": "2020 daily seawater carbonate chemistry; 2023 daily seawater carbonate chemistry; Amphipod counts from 2020 ocean acidification experiment", "datasets": [{"dataset_uid": "601701", "doi": "10.15784/601701", "keywords": "Antarctica; Cryosphere; Palmer Station", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "2023 daily seawater carbonate chemistry", "url": "https://www.usap-dc.org/view/dataset/601701"}, {"dataset_uid": "601702", "doi": "10.15784/601702", "keywords": "Antarctica; Cryosphere; Palmer Station", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "Amphipod counts from 2020 ocean acidification experiment", "url": "https://www.usap-dc.org/view/dataset/601702"}, {"dataset_uid": "601700", "doi": "10.15784/601700", "keywords": "Antarctica; Cryosphere; Palmer Station", "people": "Amsler, Charles", "repository": "USAP-DC", "science_program": null, "title": "2020 daily seawater carbonate chemistry", "url": "https://www.usap-dc.org/view/dataset/601700"}], "date_created": "Mon, 21 Jun 2021 00:00:00 GMT", "description": "Undersea forests of seaweeds dominate the shallow waters of the central and northern coast of the western Antarctic Peninsula and provide critical structural habitat and carbon resources (food) for a host of marine organisms. Most of the seaweeds are chemically defended against herbivores yet support very high densities of herbivorous shrimp-like grazers (crustaceans, primarily amphipods) which greatly benefit their hosts by consuming filamentous and microscopic algae that otherwise overgrow the seaweeds. The amphipods benefit from the association with the chemically defended seaweeds by gaining an associational refuge from fish predation. The project builds on recent work that has demonstrated that several species of amphipods that are key members of crustacean assemblages associated with the seaweeds suffer significant mortality when chronically exposed to increased seawater acidity (reduced pH) and elevated temperatures representative of near-future oceans. By simulating these environmental conditions in the laboratory at Palmer Station, Antarctica, the investigators will test the overall hypothesis that ocean acidification will play a significant role in structuring crustacean assemblages associated with seaweeds. Broader impacts include expanding fundamental knowledge of the impacts of global climate change by focusing on a geographic region of the earth uniquely susceptible to climate change. This project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This includes training graduate students and early career scientists with an emphasis on diversity, presentations to K-12 groups and the general public, and a variety of social media-based outreach programs.\r\n\r\nThe project will compare population and assemblage-wide impacts of natural (ambient) and carbon dioxide enriched seawater on assemblages of seaweed-associated crustacean grazers. Based on prior results, it is likely that some species will be relative \"winners\" and some will be relative \"losers\" under the changed conditions. The project will then aim to carry out measurements of growth, calcification, mineralogy, the incidence of molts, and biochemical and energetic body composition for two key amphipod \"winners\" and two key amphipod \"losers\". These measurements will allow an assessment of what factors drive species-specific enhanced or diminished performance under conditions of ocean acidification and sea surface warming. The project will expand on what little is known about prospective impacts of changing conditions on benthic marine Crustacea, in Antarctica, a taxonomic group that faces the additional physiological stressor of molting. The project is likely to provide additional insight on the indirect regulation of the seaweeds that comprise Antarctic undersea forests that provide key architectural components of the coastal marine ecosystem.", "east": -64.0527, "geometry": "POINT(-64.0527 -64.77423)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; AMD; AMD/US; COASTAL; BENTHIC; USAP-DC; Palmer Station; ANIMALS/INVERTEBRATES; FIELD INVESTIGATION; MACROALGAE (SEAWEEDS)", "locations": "Palmer Station", "north": -64.77423, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Amsler, Charles; McClintock, James", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.77423, "title": "Assemblage-wide effects of ocean acidification and ocean warming on ecologically important macroalgal-associated crustaceans in Antarctica", "uid": "p0010193", "west": -64.0527}, {"awards": "2048840 Chambers, Don", "bounds_geometry": "POLYGON((0 -30,15 -30,30 -30,45 -30,60 -30,75 -30,90 -30,105 -30,120 -30,135 -30,150 -30,150 -33.5,150 -37,150 -40.5,150 -44,150 -47.5,150 -51,150 -54.5,150 -58,150 -61.5,150 -65,135 -65,120 -65,105 -65,90 -65,75 -65,60 -65,45 -65,30 -65,15 -65,0 -65,0 -61.5,0 -58,0 -54.5,0 -51,0 -47.5,0 -44,0 -40.5,0 -37,0 -33.5,0 -30))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 16 Jun 2021 00:00:00 GMT", "description": "We propose to better characterize the role of eddies in wintertime air-sea carbon dioxide (CO2) fluxes in the Indian sector of the Southern Ocean using two autonomous sailing vehicles called Saildrones during austral winter 2021. The Saildrones will carry sensors to directly measure atmospheric and oceanic concentrations of CO2 (pCO2), atmospheric pressure, and wind speed to allow calculation of air-sea CO2 flux at 5-km resolution and similar accuracy to an underway ship-based measurement. The Saildrone data from this mission, a 2019 mission, and BGC Argo float data from 2014\u20132020 will be co-located with eddies derived from satellite altimetry to quantify the relationships between eddies and ocean carbon content. The overall objectives of this project are to determine the relationship between wintertime pCO2 variability and the presence and structure of eddies and to use these relationships to create a better representation of mesoscale variability in Southern Ocean CO2 flux.\r\n", "east": 150.0, "geometry": "POINT(75 -47.5)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; OCEAN MIXED LAYER; Argo float; Southern Ocean; SHIPS; PH; OCEAN CHEMISTRY; AMD/US; CO2; DISSOLVED GASES; USAP-DC; Saildrone; AMD", "locations": "Southern Ocean", "north": -30.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Williams, Nancy; Chambers, Don; Lindstrom, Eric; Carter, Brendan", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repositories": null, "science_programs": null, "south": -65.0, "title": "The Role of Cyclonic Upwelling Eddies in Southern Ocean CO2 Flux", "uid": "p0010191", "west": 0.0}, {"awards": "1543344 Soreghan, Gerilyn", "bounds_geometry": null, "dataset_titles": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "datasets": [{"dataset_uid": "601599", "doi": "10.15784/601599", "keywords": "Antarctica; Anza Borrego; Cryosphere; Iceland; McMurdo Dry Valleys; Norway; Peru; Puerto Rico; Taylor Valley; Washington; Wright Valley", "people": "Demirel-Floyd, Cansu", "repository": "USAP-DC", "science_program": null, "title": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "url": "https://www.usap-dc.org/view/dataset/601599"}], "date_created": "Tue, 18 May 2021 00:00:00 GMT", "description": "As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high \"weatherability\" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth\u0027s carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential \"weather ability\" and investigate how sediment produced in these glacial systems could ultimately impact Earth\u0027s carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.\r\n\r\nPhysical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; FIELD INVESTIGATION; weathering ; USA/NSF; Dry Valleys; SEDIMENT CHEMISTRY; Antarctica; AMD/US", "locations": "Antarctica; Dry Valleys", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soreghan, Gerilyn; Elwood Madden, Megan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems", "uid": "p0010181", "west": null}, {"awards": "1744755 Ito, Takamitsu", "bounds_geometry": "POLYGON((-80 -45,-75 -45,-70 -45,-65 -45,-60 -45,-55 -45,-50 -45,-45 -45,-40 -45,-35 -45,-30 -45,-30 -47.5,-30 -50,-30 -52.5,-30 -55,-30 -57.5,-30 -60,-30 -62.5,-30 -65,-30 -67.5,-30 -70,-35 -70,-40 -70,-45 -70,-50 -70,-55 -70,-60 -70,-65 -70,-70 -70,-75 -70,-80 -70,-80 -67.5,-80 -65,-80 -62.5,-80 -60,-80 -57.5,-80 -55,-80 -52.5,-80 -50,-80 -47.5,-80 -45))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 23 Mar 2021 00:00:00 GMT", "description": "Current generation of coupled climate models, that are used to make climate projections, lack the resolution to adequately resolve ocean mesoscale (10 - 100km) processes, exhibiting significant biases in the ocean carbon uptake. Mesoscale processes include many features including jets, fronts and eddies that are crucial for bio-physical interactions, air-sea CO2 exchange and the supply of iron to the surface ocean. This modeling project will support the eddy resolving regional simulations to understand the mechanisms that drives bio-physical interaction and air-sea exchange of carbon dioxide. ", "east": -30.0, "geometry": "POINT(-55 -57.5)", "instruments": null, "is_usap_dc": true, "keywords": "COMPUTERS; OCEAN CHEMISTRY; AMD/US; Drake Passage; air-sea carbon transfer; AMD; USA/NSF; USAP-DC", "locations": "Drake Passage", "north": -45.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Ito, Takamitsu", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS", "repositories": null, "science_programs": null, "south": -70.0, "title": "A mechanistic study of bio-physical interaction and air-sea carbon transfer in the Southern Ocean", "uid": "p0010166", "west": -80.0}, {"awards": "1842115 Jahn, Alexandra; 1842176 Bizimis, Michael; 1842059 Huber, Matthew; 1842049 Kim, Sora", "bounds_geometry": "POLYGON((-56.693516 -64.209061,-56.6823452 -64.209061,-56.6711744 -64.209061,-56.6600036 -64.209061,-56.6488328 -64.209061,-56.637662 -64.209061,-56.6264912 -64.209061,-56.6153204 -64.209061,-56.6041496 -64.209061,-56.5929788 -64.209061,-56.581808 -64.209061,-56.581808 -64.2143344,-56.581808 -64.2196078,-56.581808 -64.2248812,-56.581808 -64.2301546,-56.581808 -64.235428,-56.581808 -64.2407014,-56.581808 -64.2459748,-56.581808 -64.2512482,-56.581808 -64.2565216,-56.581808 -64.261795,-56.5929788 -64.261795,-56.6041496 -64.261795,-56.6153204 -64.261795,-56.6264912 -64.261795,-56.637662 -64.261795,-56.6488328 -64.261795,-56.6600036 -64.261795,-56.6711744 -64.261795,-56.6823452 -64.261795,-56.693516 -64.261795,-56.693516 -64.2565216,-56.693516 -64.2512482,-56.693516 -64.2459748,-56.693516 -64.2407014,-56.693516 -64.235428,-56.693516 -64.2301546,-56.693516 -64.2248812,-56.693516 -64.2196078,-56.693516 -64.2143344,-56.693516 -64.209061))", "dataset_titles": "Data from: Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota", "datasets": [{"dataset_uid": "200183", "doi": "https://doi.org/10.6071/M34T1Z", "keywords": null, "people": null, "repository": "Dryad", "science_program": null, "title": "Data from: Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota", "url": "https://datadryad.org/stash/dataset/doi:10.6071/M34T1Z"}], "date_created": "Tue, 15 Dec 2020 00:00:00 GMT", "description": "The Earth\u0027s climate has changed through time and during the Eocene Epoch (56 to 34 million years ago) there was a transition from \u0027greenhouse\u0027 to \u0027icehouse\u0027 conditions. During the Eocene, a shift to cooler temperatures at high latitudes resulted in the inception of polar glaciation. This in turn affected the environment for living organisms. This project looks to uncover the interaction between biological, oceanographic, and climate systems for the Eocene in Antarctica using chemical analysis of fossil shark teeth collected during past expeditions. The combination of paleontological and geochemical analyses will provide insight to the past ecology and ocean conditions; climate models will be applied to test the role of tectonics, greenhouse gas concentration and ocean circulation on environmental change during this time period. The study contributes to understanding the interaction of increased atmospheric carbon dioxide and ocean circulation. This project also seeks to improve diversity, equity, and inclusion within the geosciences workforce with efforts targeted to undergraduate, graduate, postdoctoral, and early career faculty.\u003cbr/\u003e\u003cbr/\u003eThe research goal is to elucidate the processes leading from the Eocene greenhouse to Oligocene icehouse conditions. Previous explanations for this climate shift centers on Antarctica, where tectonic configurations influenced oceanic gateways, ocean circulation reduced heat transport, and/or greenhouse gas declines prompted glaciation. The team will reconstruct watermass, current, and climate fluctuations proximal to the Antarctic Peninsula using geochemical indicators (oxygen and neodymium isotope composition) from fossil shark teeth collected from Seymour Island. The approach builds on previous shark paleontological studies, incorporates geochemical analyses for environmental reconstruction (i.e., temperature gradients and ocean circulation), and tests hypotheses on Earth System dynamics using novel global climate model simulations with geochemical tracers. This project will advance global climate modeling capabilities with experiments that consider Eocene tectonic configuration within isotope-enabled climate model simulations. A comparison of geochemical results from Eocene climate simulations and empirical records of shark teeth will reveal processes and mechanisms central to the Eocene Antarctic climatic shift.\u003cbr/\u003e\u003cbr/\u003eThis 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": -56.581808, "geometry": "POINT(-56.637662 -64.235428)", "instruments": null, "is_usap_dc": true, "keywords": "FISH; USA/NSF; OXYGEN ISOTOPE ANALYSIS; WATER MASSES; AMD/US; AMD; USAP-DC; OXYGEN ISOTOPES; LABORATORY; Striatolamia macrota; Seymour Island; Sharks", "locations": "Seymour Island", "north": -64.209061, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE \u003e EOCENE", "persons": "Kim, Sora; Scher, Howard; Huber, Matthew; Jahn, Alexandra", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "Dryad", "repositories": "Dryad", "science_programs": null, "south": -64.261795, "title": "Collaborative Research: Integrating Eocene Shark Paleoecology and Climate Modeling to reveal Southern Ocean Circulation and Antarctic Glaciation", "uid": "p0010146", "west": -56.693516}, {"awards": "1043623 Miller, Scott", "bounds_geometry": "POLYGON((117.5 -47,120.35 -47,123.2 -47,126.05 -47,128.9 -47,131.75 -47,134.6 -47,137.45 -47,140.3 -47,143.15 -47,146 -47,146 -49.04,146 -51.08,146 -53.12,146 -55.16,146 -57.2,146 -59.24,146 -61.28,146 -63.32,146 -65.36,146 -67.4,143.15 -67.4,140.3 -67.4,137.45 -67.4,134.6 -67.4,131.75 -67.4,128.9 -67.4,126.05 -67.4,123.2 -67.4,120.35 -67.4,117.5 -67.4,117.5 -65.36,117.5 -63.32,117.5 -61.28,117.5 -59.24,117.5 -57.2,117.5 -55.16,117.5 -53.12,117.5 -51.08,117.5 -49.04,117.5 -47))", "dataset_titles": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1210; Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1402; Expedition Data", "datasets": [{"dataset_uid": "001427", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1210"}, {"dataset_uid": "001414", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1402"}, {"dataset_uid": "601308", "doi": null, "keywords": "Air-Sea Flux; Air Temperature; Antarctica; Atmosphere; CO2; CO2 concentrations; Cryosphere; East Antarctica; Flux; Meteorology; NBP1402; Oceans; Relative Humidity; Salinity; Totten Glacier; Water Measurements; Water Temperature; Weather Station Data; Wind Direction; Wind Speed", "people": "Miller, Scott; Butterworth, Brian", "repository": "USAP-DC", "science_program": null, "title": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1402", "url": "https://www.usap-dc.org/view/dataset/601308"}, {"dataset_uid": "601309", "doi": "10.15784/601309", "keywords": "Air-Sea Flux; Air Temperature; Amundsen Sea; Antarctica; Antarctic Peninsula; Atmosphere; CO2; Flux; Meteorology; NBP1210; Oceans; Ross Sea; R/V Nathaniel B. Palmer; Southern Ocean; Water Temperature; Wind Direction; Wind Speed", "people": "Miller, Scott; Butterworth, Brian", "repository": "USAP-DC", "science_program": null, "title": "Eddy covariance air-sea momentum, heat, and carbon dioxide fluxes in the Southern Ocean from the N.B. Palmer cruise NBP1210", "url": "https://www.usap-dc.org/view/dataset/601309"}], "date_created": "Fri, 09 Oct 2020 00:00:00 GMT", "description": "Accurate parameterizations of the air-sea fluxes of CO2 into the Southern Ocean, in particular at high wind velocity, are needed to better assess how projections of global climate warming in a windier world could affect the ocean carbon uptake, and alter the ocean heat budget at high latitudes. \u003cbr/\u003e\u003cbr/\u003eAir-sea fluxes of momentum, sensible and latent heat (water vapor) and carbon dioxide (CO2) are to be measured continuously underway on cruises using micrometeorological eddy covariance techniques adapted to ship-board use. The measured gas transfer velocity (K) is then to be related to other parameters known to affect air-sea-fluxes.\u003cbr/\u003e\u003cbr/\u003eA stated goal of this work is the collection of a set of direct air-sea flux measurements at high wind speeds, conditions where parameterization of the relationship of gas exchange to wind-speed remains contentious. The studies will be carried out at sites in the Southern Ocean using the USAP RV Nathaniel B Palmer as measurment platform. Co-located pCO2 data, to be used in the overall analysis and enabling internal consistency checks, are being collected from existing underway systems aboard the USAP research vessel under other NSF awards.", "east": 146.0, "geometry": "POINT(131.75 -57.2)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "HEAT FLUX; DISSOLVED GASES; Antarctica; USAP-DC; NOT APPLICABLE", "locations": "Antarctica", "north": -47.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Miller, Scott", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.4, "title": "Air-Sea Fluxes of Momentum, Heat, and Carbon Dioxide at High Wind Speeds in the Southern Ocean", "uid": "p0010137", "west": 117.5}, {"awards": "1542962 Anderson, Robert", "bounds_geometry": "POLYGON((-171 -57,-170.8 -57,-170.6 -57,-170.4 -57,-170.2 -57,-170 -57,-169.8 -57,-169.6 -57,-169.4 -57,-169.2 -57,-169 -57,-169 -57.72,-169 -58.44,-169 -59.16,-169 -59.88,-169 -60.6,-169 -61.32,-169 -62.04,-169 -62.76,-169 -63.48,-169 -64.2,-169.2 -64.2,-169.4 -64.2,-169.6 -64.2,-169.8 -64.2,-170 -64.2,-170.2 -64.2,-170.4 -64.2,-170.6 -64.2,-170.8 -64.2,-171 -64.2,-171 -63.48,-171 -62.76,-171 -62.04,-171 -61.32,-171 -60.6,-171 -59.88,-171 -59.16,-171 -58.44,-171 -57.72,-171 -57))", "dataset_titles": "Expedition Data of NBP1702; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ; Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "datasets": [{"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "200166", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean ", "url": "https://www.ncdc.noaa.gov/paleo/study/31312"}, {"dataset_uid": "200165", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean (SNOWBIRDS)", "url": "https://www.bco-dmo.org/dataset/813379/data"}], "date_created": "Fri, 25 Sep 2020 00:00:00 GMT", "description": "General:\r\nScientists established more than 30 years ago that the climate-related variability of carbon dioxide levels in the atmosphere over Earth\u2019s ice-age cycles was regulated by the ocean. Hypotheses to explain how the ocean that regulates atmospheric carbon dioxide have long been debated, but they have proven to be difficult to test. This project was designed test one leading hypothesis, specifically that the ocean experienced greater density stratification during the ice ages. That is, with greater stratification during the ice ages and the slower replacement of deep water by cold dense water formed near the poles, the deep ocean would have held more carbon dioxide, which is produced by biological respiration of the organic carbon that constantly rains to the abyss in the form of dead organisms and organic debris that sink from the sunlit surface ocean. To test this hypothesis, the degree of ocean stratification during the last ice age and the rate of deep-water replacement was to be constrained by comparing the radiocarbon ages of organisms that grew in the surface ocean and at the sea floor within a critical region around Antarctica, where most of the replacement of deep waters occurs. Completing this work was expected to contribute toward improved models of future climate change. Climate scientists rely on models to estimate the amount of fossil fuel carbon dioxide that will be absorbed by the ocean in the future. Currently the ocean absorbs about 25% of the carbon dioxide produced by burning fossil fuels. Most of this carbon is absorbed in the Southern Ocean (the region around Antarctica). How this will change in the future is poorly known. Models have difficulty representing physical conditions in the Southern Ocean accurately, thereby adding substantial uncertainty to projections of future ocean uptake of carbon dioxide. Results of the proposed study will provide a benchmark to test the ability of models to simulate ocean processes under climate conditions distinctly different from those that occur today, ultimately leading to improvement of the models and to more reliable projections of future absorption of carbon dioxide by the ocean. \r\n\r\nTechnical:\r\nThe project added a research component to an existing scientific expedition to the Southern Ocean, in the region between the Ross Sea and New Zealand, that collected sediment cores at locations down the northern flank of the Pacific-Antarctic Ridge at approximately 170\u00b0W. The goal was to collect sediments at each location deposited since early in the peak of the last ice age. This region is unusual in the Southern Ocean in that sediments deposited during the last ice age contain foraminifera, tiny organisms with calcium carbonate shells, in much greater abundance than in other regions of the Southern Ocean. Foraminifera are widely used as an archive of several geochemical tracers of past ocean conditions. We proposed to compare the radiocarbon age of foraminifera that inhabited the surface ocean with the age of contemporary specimens that grew on the seabed. The difference in age between surface and deep-swelling organisms would have been used to discriminate between two proposed mechanisms of deep water renewal during the ice age: formation in coastal polynyas around the edge of Antarctica, much as occurs today, versus formation by open-ocean convection in deep-water regions far from the continent. If the latter mechanism prevails, then it was expected that surface and deep-dwelling foraminifera would exhibit similar radiocarbon ages. In the case of dominance of deep-water formation in coastal polynyas, one expects to find very different radiocarbon ages in the two populations of foraminifera. In the extreme case of greater ocean stratification during the last ice age, one even expects the surface dwellers to appear to be older than contemporary bottom dwellers because the targeted core sites lie directly under the region where the oldest deep waters outcrop at the surface following their long circuitous transit through the deep ocean. The primary objective of the proposed work was to reconstruct the water mass age structure of the Southern Ocean during the last ice age, which, in turn, is a primary factor that controls the amount of carbon dioxide stored in the deep sea. In addition, the presence of foraminifera in the cores to be recovered provides a valuable resource for many other paleoceanographic applications, such as: 1) the application of nitrogen isotopes to constrain the level of nutrient utilization in the Southern Ocean and, thus, the efficiency of the ocean\u2019s biological pump, 2) the application of neodymium isotopes to constrain the transport history of deep water masses, 3) the application of boron isotopes and boron/calcium ratios to constrain the pH and inorganic carbon system parameters of ice-age seawater, and 4) the exploitation of metal/calcium ratios in foraminifera to reconstruct the temperature (Mg/Ca) and nutrient content (Cd/Ca) of deep waters during the last ice age at a location near their source near Antarctica. \r\n\r\nUnfortunately, the cores were shipped to the core repository in a horizontal orientation and there was sufficient distortion of the sediment that the radiocarbon ages of benthic foraminifera were uninterpretable. Therefore, we report only the radiocarbon dates for planktonic foraminifera as well as the total counts of elemental relative abundance from X-ray Fluorescence analysis of the cores. In addition, we used the expedition as an opportunity to collect water samples from which dissolved concentrations of long-lived isotope of thorium and protactinium were determined. Results from those analyses showed that lateral transport by isopycnal mixing dominates the supply of Pa to the Southern Ocean. We have also developed a new algorithm to correct for supply of Th by isopycnal mixing and thereby derive estimates of dust flux to the Southern Ocean. \r\n", "east": -169.0, "geometry": "POINT(-170 -60.6)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; SEDIMENT CHEMISTRY; South Pacific Ocean; SHIPS", "locations": "South Pacific Ocean", "north": -57.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Fleisher, Martin; Pavia, Frank", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "BCO-DMO; NCEI; R2R", "science_programs": null, "south": -64.2, "title": "Water Mass Structure and Bottom Water Formation in the Ice-age Southern Ocean", "uid": "p0010130", "west": -171.0}, {"awards": "1935755 Lamp, Jennifer; 1935945 Tremblay, Marissa; 1935907 Balco, Gregory", "bounds_geometry": "POLYGON((160 -77.25,160.4 -77.25,160.8 -77.25,161.2 -77.25,161.6 -77.25,162 -77.25,162.4 -77.25,162.8 -77.25,163.2 -77.25,163.6 -77.25,164 -77.25,164 -77.325,164 -77.4,164 -77.475,164 -77.55,164 -77.625,164 -77.7,164 -77.775,164 -77.85,164 -77.925,164 -78,163.6 -78,163.2 -78,162.8 -78,162.4 -78,162 -78,161.6 -78,161.2 -78,160.8 -78,160.4 -78,160 -78,160 -77.925,160 -77.85,160 -77.775,160 -77.7,160 -77.625,160 -77.55,160 -77.475,160 -77.4,160 -77.325,160 -77.25))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 25 Aug 2020 00:00:00 GMT", "description": "Part I: Nontechnical\r\nScientists study the Earth\u0027s past climate in order to understand how the climate will respond to ongoing global change in the future. One of the best analogs for future climate might the period that occurred approximately 3 million years ago, during an interval known as the mid-Pliocene Warm Period. During this period, the concentration of carbon dioxide in the atmosphere was similar to today\u0027s and sea level was 15 or more meters higher, due primarily to warming and consequent ice sheet melting in polar regions. However, the temperatures in polar regions during the mid-Pliocene Warm Period are not well determined, in part because we do not have records like ice cores that extend this far back in time. This project will provide constraints on surface temperatures in Antarctica during the mid-Pliocene Warm Period using a new type of climate proxy, known as cosmogenic noble gas paleothermometry. This project focuses on an area of Antarctica called the McMurdo Dry Valleys. In this area, climate models suggest that temperatures were more than 10 \u00baC warmer during the mid-Pliocene than they are today, but indirect geologic observations suggest that temperatures may have been similar to today. The McMurdo Dry Valleys are also a place where rocks have been exposed to Earth surface conditions for several million years, and where this new climate proxy can be readily applied. The team will reconstruct temperatures in the McMurdo Dry Valleys during the mid-Pliocene Warm Period in order to resolve the discrepancy between models and indirect geologic observations and provide much-needed constraints on the sensitivity of Antarctic ice sheets to warming temperatures. The temperature reconstructions generated in this project will have scientific impact in multiple disciplines, including climate science, glaciology, geomorphology, and planetary science. In addition, the project will (1) broaden the participation of underrepresented groups by supporting two early-career female principal investigators, (2) build STEM talent through the education and training of a graduate student, (3) enhance infrastructure for research via publication of a publicly-accessible, open-source code library, and (4) be broadly disseminated via social media, blog posts, publications, and conference presentations. \r\n\r\nPart II: Technical Description\r\nThe mid-Pliocene Warm Period (3\u20133.3 million years ago) is the most recent interval of the geologic past when atmospheric CO2 concentrations exceeded 400 ppm, and is widely considered an analog for how Earths climate system will respond to current global change. Climate models predict polar amplification the occurrence of larger changes in temperatures at high latitudes than the global average due to a radiative forcing both during the mid-Pliocene Warm Period and due to current climate warming. However, the predicted magnitude of polar amplification is highly uncertain in both cases. The magnitude of polar amplification has important implications for the sensitivity of ice sheets to warming and the contribution of ice sheet melting to sea level change. Proxy-based constraints on polar surface air temperatures during the mid-Pliocene Warm Period are sparse to non-existent. In Antarctica, there is only indirect evidence for the magnitude of warming during this time. This project will provide constraints on surface temperatures in the McMurdo Dry Valleys of Antarctica during the mid-Pliocene Warm Period using a newly developed technique called cosmogenic noble gas (CNG) paleothermometry. CNG paleothermometry utilizes the diffusive behavior of cosmogenic 3He in quartz to quantify the temperatures rocks experience while exposed to cosmic-ray particles within a few meters of the Earths surface. The very low erosion rates and subzero temperatures characterizing the McMurdo Dry Valleys make this region uniquely suited for the application of CNG paleothermometry for addressing the question: what temperatures characterized the McMurdo Dry Valleys during the mid-Pliocene Warm Period? To address this question, the team will collect bedrock samples at several locations in the McMurdo Dry Valleys where erosion rates are known to be low enough that cosmic ray exposure extends into the mid-Pliocene or earlier. They will pair cosmogenic 3He measurements, which will record the thermal histories of our samples, with measurements of cosmogenic 10Be, 26Al, and 21Ne, which record samples exposure and erosion histories. We will also make in situ measurements of rock and air temperatures at sample sites in order to quantify the effect of radiative heating and develop a statistical relationship between rock and air temperatures, as well as conduct diffusion experiments to quantify the kinetics of 3He diffusion specific to each sample. This suite of observations will be used to model permissible thermal histories and place constraints on temperatures during the mid-Pliocene Warm Period interval of cosmic-ray exposure.", "east": 164.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; AMD/US; AMD; LABORATORY; USA/NSF; ISOTOPES; Dry Valleys; AIR TEMPERATURE RECONSTRUCTION; GEOCHEMISTRY; USAP-DC", "locations": "Dry Valleys", "north": -77.25, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Tremblay, Marissa; Granger, Darryl; Balco, Gregory; Lamp, Jennifer", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -78.0, "title": "Collaborative \r\nResearch: Reconstructing Temperatures during the Mid-Pliocene Warm \r\nPeriod in the McMurdo Dry Valleys with Cosmogenic Noble Gases", "uid": "p0010123", "west": 160.0}, {"awards": "1543483 Sedwick, Peter", "bounds_geometry": "POLYGON((-180 -66,-179.5 -66,-179 -66,-178.5 -66,-178 -66,-177.5 -66,-177 -66,-176.5 -66,-176 -66,-175.5 -66,-175 -66,-175 -67.2,-175 -68.4,-175 -69.6,-175 -70.8,-175 -72,-175 -73.2,-175 -74.4,-175 -75.6,-175 -76.8,-175 -78,-175.5 -78,-176 -78,-176.5 -78,-177 -78,-177.5 -78,-178 -78,-178.5 -78,-179 -78,-179.5 -78,180 -78,178.5 -78,177 -78,175.5 -78,174 -78,172.5 -78,171 -78,169.5 -78,168 -78,166.5 -78,165 -78,165 -76.8,165 -75.6,165 -74.4,165 -73.2,165 -72,165 -70.8,165 -69.6,165 -68.4,165 -67.2,165 -66,166.5 -66,168 -66,169.5 -66,171 -66,172.5 -66,174 -66,175.5 -66,177 -66,178.5 -66,-180 -66))", "dataset_titles": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle; NBP1704 Expedition Data", "datasets": [{"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}, {"dataset_uid": "200150", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "url": "https://www.bco-dmo.org/project/815403"}], "date_created": "Mon, 22 Jun 2020 00:00:00 GMT", "description": "The waters of the Ross Sea continental shelf are among the most productive in the Southern Ocean, and may comprise a significant regional oceanic sink for atmospheric carbon dioxide. In this region, primary production can be limited by the supply of dissolved iron to surface waters during the growing season. Water-column observations, sampling and measurements are to be carried out in the late autumn-early winter time frame on the Ross Sea continental shelf and coastal polynyas (Terra Nova Bay and Ross Ice Shelf polynyas), in order to better understand what drives the biogeochemical redistribution of micronutrient iron species during the onset of convective mixing and sea-ice formation at this time of year, thereby setting conditions for primary production during the following spring. The spectacular field setting and remote, hostile conditions that accompany the proposed field study present exciting possibilities for STEM education and training. At the K-12 level, the project seeks to support the development of educational outreach materials targeting elementary and middle school students, pre-service science teachers, and in-service science teachers.", "east": 165.0, "geometry": "POINT(175 -72)", "instruments": null, "is_usap_dc": true, "keywords": "POLYNYAS; USAP-DC; NBP1704; Iron; Ross Sea; TRACE ELEMENTS; SALINITY/DENSITY; R/V NBP; MARINE ECOSYSTEMS; BIOGEOCHEMICAL CYCLES", "locations": "Ross Sea", "north": -66.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sedwick, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -78.0, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "uid": "p0010111", "west": -175.0}, {"awards": "1246465 Brook, Edward", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "WAIS Divide Ice Core Marine Isotope Stage 3 CO2 record", "datasets": [{"dataset_uid": "601337", "doi": "10.15784/601337", "keywords": "Antarctica; Carbon Cycle; CO2; Cryosphere; Gas Chromatograph; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; WAIS divide", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice Core Marine Isotope Stage 3 CO2 record", "url": "https://www.usap-dc.org/view/dataset/601337"}], "date_created": "Mon, 22 Jun 2020 00:00:00 GMT", "description": "This award supports a project to measure the carbon dioxide (CO2) concentration in the WAIS Divide ice core covering the time period 25,000 to 60,000 years before present, and to analyze the isotopic composition of CO2 in selected time intervals. The research will improve understanding of how and why atmospheric CO2 varied during the last ice age, focusing particularly on abrupt transitions in the concentration record that are associated with abrupt climate change. These events represents large perturbations to the global climate system and better information about the CO2 response should inform our understanding of carbon cycle-climate feedbacks and radiative forcing of climate. The research will also improve analytical methods in support of these goals, including completing development of sublimation methods to replace laborious mechanical crushing of ice to release air for analysis. The intellectual merit of the proposed work is that it will increase knowledge about the magnitude and timing of atmospheric CO2 variations during the last ice age, and their relationship to regional climate in Antarctica, global climate history, and the history of abrupt climate change in the Northern Hemisphere. The temporal resolution of the proposed record will in most intervals be ~ 4 x higher than previous data sets for this time period, and for selected intervals up to 8-10 times higher. Broader impacts of the proposed work include a significant addition to the amount of data documenting the history of the most important long-lived greenhouse gas in the atmosphere and more information about carbon cycle-climate feedbacks - important parameters for predicting future climate change. The project will contribute to training a postdoctoral researcher, research experience for an undergraduate and a high school student, and outreach to local middle school and other students. It will also improve the analytical infrastructure at OSU, which will be available for future projects.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ice Core Records; USAP-DC; CO2; FIELD INVESTIGATION; CARBON DIOXIDE; WAIS divide; LABORATORY; Carbon Cylce", "locations": "WAIS divide", "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Completing the WAIS Divide Ice Core CO2 record", "uid": "p0010110", "west": -112.1115}, {"awards": "1643722 Brook, Edward", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "South Pole Ice Core Methane Data and Gas Age Time Scale; South Pole ice core (SPC14) total air content (TAC)", "datasets": [{"dataset_uid": "601329", "doi": "10.15784/601329", "keywords": "Antarctica; Cryosphere; Gas Chromatography; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; South Pole", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Methane Data and Gas Age Time Scale", "url": "https://www.usap-dc.org/view/dataset/601329"}, {"dataset_uid": "601546", "doi": "10.15784/601546", "keywords": "Antarctica; Cryosphere; South Pole", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) total air content (TAC)", "url": "https://www.usap-dc.org/view/dataset/601546"}], "date_created": "Tue, 02 Jun 2020 00:00:00 GMT", "description": "This award supports a project to measure the concentration of the gas methane in air trapped in an ice core collected from the South Pole. The data will provide an age scale (age as a function of depth) by matching the South Pole methane changes with similar data from other ice cores for which the age vs. depth relationship is well known. The ages provided will allow all other gas measurements made on the South Pole core (by the PI and other NSF supported investigators) to be interpreted accurately as a function of time. This is critical because a major goal of the South Pole coring project is to understand the history of rare gases in the atmosphere like carbon monoxide, carbon dioxide, ethane, propane, methyl chloride, and methyl bromide. Relatively little is known about what controls these gases in the atmosphere despite their importance to atmospheric chemistry and climate. Undergraduate assistants will work on the project and be introduced to independent research through their work. The PI will continue visits to local middle schools to introduce students to polar science, and other outreach activities (e.g. laboratory tours, talks to local civic or professional organizations) as part of the project. \u003cbr/\u003e\u003cbr/\u003eMethane concentrations from a major portion (2 depth intervals, excluding the brittle ice-zone which is being measured at Penn State University) of the new South Pole ice core will be used to create a gas chronology by matching the new South Pole ice core record with that from the well-dated WAIS Divide ice core record. In combination with measurements made at Penn State, this will provide gas dating for the entire 50,000-year record. Correlation will be made using a simple but powerful mid-point method that has been previously demonstrated, and other methods of matching records will be explored. The intellectual merit of this work is that the gas chronology will be a fundamental component of this ice core project, and will be used by the PI and other investigators for dating records of atmospheric composition, and determining the gas age-ice age difference independently of glaciological models, which will constrain processes that affected firn densification in the past. The methane data will also provide direct stratigraphic markers of important perturbations to global biogeochemical cycles (e.g., rapid methane variations synchronous with abrupt warming and cooling in the Northern Hemisphere) that will tie other ice core gas records directly to those perturbations. A record of the total air content will also be produced as a by-product of the methane measurements and will contribute to understanding of this parameter. The broader impacts include that the work will provide a fundamental data set for the South Pole ice core project and the age scale (or variants of it) will be used by all other investigators working on gas records from the core. The project will employ an undergraduate assistant(s) in both years who will conduct an undergraduate research project which will be part of the student\u0027s senior thesis or other research paper. The project will also offer at least one research position for the Oregon State University Summer REU site program. Visits to local middle schools, and other outreach activities (e.g. laboratory tours, talks to local civic or professional organizations) will also be part of the project.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "AMD; LABORATORY; METHANE; ICE CORE RECORDS; Gas Chromatography; South Pole; USAP-DC", "locations": "South Pole", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "A High Resolution Atmospheric Methane Record from the South Pole Ice Core", "uid": "p0010102", "west": 0.0}, {"awards": "1443470 Aydin, Murat", "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": "South Pole ice core (SPC14) discrete methane data; SP19 Gas Chronology; SPC14 carbonyl sulfide, methyl chloride, and methyl bromide measurements from South Pole, Antarctica", "datasets": [{"dataset_uid": "601270", "doi": "10.15784/601270", "keywords": "Antarctica; Cryosphere", "people": "Aydin, Murat", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPC14 carbonyl sulfide, methyl chloride, and methyl bromide measurements from South Pole, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601270"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Winski, Dominic A.; Kennedy, Joshua A.; Ferris, David G.; Kalk, Michael; Severinghaus, Jeffrey P.; Hood, Ekaterina; Fudge, T. J.; Steig, Eric J.; Osterberg, Erich; Epifanio, Jenna; Brook, Edward J.; Buizert, Christo; Kreutz, Karl; Aydin, Murat; Edwards, Jon S.; Sowers, Todd A.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}], "date_created": "Thu, 26 Mar 2020 00:00:00 GMT", "description": "In the past, Earth\u0027s climate underwent dramatic changes that influenced physical, chemical, geological, and biological processes on a global scale. Such changes left an imprint in Earth\u0027s atmosphere, as shown by the variability in abundances of trace gases like carbon dioxide and methane. In return, changes in the atmospheric trace gas composition affected Earth\u0027s climate. Studying compositional variations of the past atmosphere helps us understand the history of interactions between global biogeochemical cycles and Earth?s climate. The most reliable information on past atmospheric composition comes from analysis of air entrapped in polar ice cores. This project aims to generate ice-core records of relatively short-lived, very-low-abundance trace gases to determine the range of past variability in their atmospheric levels and investigate the changes in global biogeochemical cycles that caused this variability. This project measures three such gases: carbonyl sulfide, methyl chloride, and methyl bromide. Changes in carbonyl sulfide can indicate changes in primary productivity and photosynthetic update of carbon dioxide. Changes in methyl chloride and methyl bromide significantly impact natural variability in stratospheric ozone. In addition, the processes that control atmospheric levels of methyl chloride and methyl bromide are shared with those controlling levels of atmospheric methane. The measurements will be made in the new ice core from the South Pole, which is expected to provide a 40,000-year record.\u003cbr/\u003e\u003cbr/\u003eThe primary focus of this project is to develop high-quality trace gas records for the entire Holocene period (the past 11,000 years), with additional, more exploratory measurements from the last glacial period including the period from 29,000-36,000 years ago when there were large changes in atmospheric methane. Due to the cold temperatures of the South Pole ice, the proposed carbonyl sulfide measurements are expected to provide a direct measure of the past atmospheric variability of this gas without the large hydrolysis corrections that are necessary for interpretation of measurements from ice cores in warmer settings. Furthermore, we will test the expectation that contemporaneous measurements from the last glacial period in the deep West Antarctic Ice Sheet Divide ice core will not require hydrolysis loss corrections. With respect to methyl chloride, we aim to verify and improve the existing Holocene atmospheric history from the Taylor Dome ice core in Antarctica. The higher resolution of our measurements compared with those from Taylor Dome will allow us to derive a more statistically significant relationship between methyl chloride and methane. With respect to methyl bromide, we plan to extend the existing 2,000-year database to 11,000 years. Together, the methyl bromide and methyl chloride records will provide strong measurement-based constraints on the natural variability of stratospheric halogens during the Holocene period. In addition, the methyl bromide record will provide insight into the correlation between methyl chloride and methane during the Holocene period due to common sources and sinks.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; CARBONYL SULFIDE; HALOCARBONS AND HALOGENS; TRACE GASES/TRACE SPECIES; Antarctic; USAP-DC", "locations": "Antarctic", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Carbonyl Sulfide, Methyl Chloride, and Methyl Bromide Measurements in the New Intermediate-depth South Pole Ice Core", "uid": "p0010089", "west": -180.0}, {"awards": "1341464 Robinson, Rebecca; 1341432 Brzezinski, Mark", "bounds_geometry": "POLYGON((-175 -54,-174 -54,-173 -54,-172 -54,-171 -54,-170 -54,-169 -54,-168 -54,-167 -54,-166 -54,-165 -54,-165 -55.3,-165 -56.6,-165 -57.9,-165 -59.2,-165 -60.5,-165 -61.8,-165 -63.1,-165 -64.4,-165 -65.7,-165 -67,-166 -67,-167 -67,-168 -67,-169 -67,-170 -67,-171 -67,-172 -67,-173 -67,-174 -67,-175 -67,-175 -65.7,-175 -64.4,-175 -63.1,-175 -61.8,-175 -60.5,-175 -59.2,-175 -57.9,-175 -56.6,-175 -55.3,-175 -54))", "dataset_titles": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments; Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S; Expedition Data of NBP1702; Particle composition measurements from along 170\u00b0W between 67-54\u00b0S; Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean; Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "datasets": [{"dataset_uid": "200126", "doi": "10.7284/907211", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1702", "url": "https://www.rvdata.us/search/cruise/NBP1702"}, {"dataset_uid": "601523", "doi": "10.15784/601523", "keywords": "Antarctica; Biology; Carboy Growouts; Cryosphere; Diatom; Diatom Assemblage Data; NBP1702; Oceans; R/V Nathaniel B. Palmer; Southern Ocean; Southern Ocean Summer", "people": "Jones, Colin; Robinson, Rebecca ; Robinson, Rebecca; Riesselman, Christina", "repository": "USAP-DC", "science_program": null, "title": "Diatom assemblage counts from NBP17-02 shipboard carboy experiments", "url": "https://www.usap-dc.org/view/dataset/601523"}, {"dataset_uid": "601522", "doi": "10.15784/601522", "keywords": "Antarctica; Cryosphere; Nitrogen Isotopes; Oceans; Paleoproxies; Southern Ocean", "people": "Robinson, Rebecca; Brzezinski, Mark; Kelly, Roger; Robinson, Rebecca ; Closset, Ivia; Riesselman, Christina; Jones, Colin", "repository": "USAP-DC", "science_program": null, "title": "Surface Southern Ocean community growouts to evaluate the diatom bound N isotope proxy", "url": "https://www.usap-dc.org/view/dataset/601522"}, {"dataset_uid": "601562", "doi": "10.15784/601562", "keywords": "Antarctica; Biogenic Silica; Chemistry:Sediment; Cryosphere; Lithogenic Silica; Marine Geoscience; NBP1702; Pore Water Biogeochemistry; Sediments; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Jones, Janice L.; Brzezinski, Mark; Closset, Ivia", "repository": "USAP-DC", "science_program": null, "title": "Silicon concentration and isotopic composition measurements in pore waters and sediments from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601562"}, {"dataset_uid": "601576", "doi": "10.15784/601576", "keywords": "Antarctica; Biogenic Silica; Chemistry:Sediment; Cryosphere; Diatom; Diatom Bound; Lithogenic Silica; Marine Geoscience; NBP1702; Nitrogen Isotopes; Nitrogen Stable Isotope; Silicon Cycle; Silicon Stable Isotope; Southern Ocean", "people": "Closset, Ivia; Robinson, Rebecca; Brzezinski, Mark; Jones, Janice L.", "repository": "USAP-DC", "science_program": null, "title": " Particulate silicon and nitrogen concentrations and isotopic composition measurements in McLane pump profiles from 67\u00b0S to 55\u00b0S latitude in the Pacific Sector of the Southern Ocean", "url": "https://www.usap-dc.org/view/dataset/601576"}, {"dataset_uid": "601276", "doi": "10.15784/601276", "keywords": "Antarctica; Biogenic Silica; Cryosphere; Nitrogen Isotopes; Southern Ocean", "people": "Brzezinski, Mark; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Particle composition measurements from along 170\u00b0W between 67-54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601276"}, {"dataset_uid": "601269", "doi": "10.15784/601269", "keywords": "Antarctica; Chlorophyll; Cryosphere; Southern Ocean", "people": "Brzezinski, Mark; Robinson, Rebecca", "repository": "USAP-DC", "science_program": null, "title": "Dissolved nutrient profiles from along 170\u00b0W between 67 and 54\u00b0S", "url": "https://www.usap-dc.org/view/dataset/601269"}], "date_created": "Wed, 26 Feb 2020 00:00:00 GMT", "description": "The rise in atmospheric carbon dioxide concentrations and associated climate changes make understanding the role of the ocean in large scale carbon cycle a priority. Geologic samples allow exploration of potential mechanisms for carbon dioxide drawdown during glacial periods through the use of geochemical proxies. Nitrogen and silicon isotope signatures from fossil diatoms (microscopic plants) are used to investigate changes in the physical supply and biological demand for nutrients (like nitrogen and silicon and carbon) in the Southern Ocean. The project will evaluate the use the nitrogen and silicon isotope proxies through a series of laboratory experiments and Southern Ocean field sampling. The results will provide quantification of real relationships between nitrogen and silicon isotopes and nutrient usage in the Southern Ocean and allow exploration of the role of other factors, including biological diversity, ice cover, and mixing, in altering the chemical signatures recorded by diatoms. Seafloor sediment samples will be used to evaluate how well the signal created in the water column is recorded by fossil diatoms buried in the seafloor. Improving the nutrient isotope proxies will allow for a more quantitative understanding of the role of polar biology in regulating natural variation in atmospheric carbon dioxide. The project will also result in the training of a graduate student and development of outreach materials targeting a broad popular audience.\r\n\r\nThis project seeks to test the fidelity of the diatom nitrogen and silicon isotope proxies, two commonly used paleoceanographic tools for investigating the role of the Southern Ocean biological pump in regulating atmospheric CO2 concentrations on glacial-interglacial timescales. Existing ground-truthing data, including culture experiments, surface sediment data and downcore reconstructions, all suggest that nutrient utilization is the primary driver of isotopic variation in the Southern Ocean. However, strong contribution of interspecific variation is implied by recent culture results. Moreover, field and laboratory studies present some contradictory results in terms of the relative importance of interspecific variation and of inferred post-depositional alteration of the nutrient isotope signals. Here, a first order test of the N and Si diatom nutrient isotope paleo-proxies, involving water column dissolved and particulate sampling and laboratory culturing of field-isolates, is proposed. Southern Ocean water, biomass, live diatoms and fossil diatom sampling will be conducted to investigate species and assemblage related variability in diatom nitrogen and silicon isotopes and their relationship to surface nutrient fields and early diagenesis. Access to fresh materials produced in an analogous environmental context to the sediments of primary interest is critical for making robust paleoceanographic reconstructions. Field sampling will occur along 175\u00b0W, transecting the Antarctic Circumpolar Current from the subtropics to the marginal ice edge. Collection of water, sinking/suspended particles and multi-core samples from 13 stations and 3 shipboard incubation experiments will be used to test four proposed hypotheses that together evaluate the significance of existing culture results and seek to allow the best use of diatom nutrient isotope proxies in evaluating the biological pump.", "east": -165.0, "geometry": "POINT(-170 -60.5)", "instruments": null, "is_usap_dc": true, "keywords": "Southern Ocean; AMD; NITROGEN ISOTOPES; R/V NBP; AMD/US; NSF/USA; NUTRIENTS; USAP-DC", "locations": "Southern Ocean", "north": -54.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Robinson, Rebecca; Brzezinski, Mark", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -67.0, "title": "Collaborative Proposal: A Field and Laboratory Examination of the Diatom N and Si Isotope Proxies: Implications for Assessing the Southern Ocean Biological Pump", "uid": "p0010083", "west": -175.0}, {"awards": "1341494 Gao, Yuan", "bounds_geometry": "POINT(-64.05 -64.77)", "dataset_titles": "Concentrations and Particle Size Distributions of Aerosol Trace Elements; Particle sizes of aerosol iron", "datasets": [{"dataset_uid": "601257", "doi": "10.15784/601257", "keywords": "Aerosol Concentration; Antarctica; Chemistry:Gas; Cryosphere; Iron; Palmer Station; Particle Size", "people": "Gao, Yuan", "repository": "USAP-DC", "science_program": null, "title": "Particle sizes of aerosol iron", "url": "https://www.usap-dc.org/view/dataset/601257"}, {"dataset_uid": "601370", "doi": "10.15784/601370", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Palmer Station; Trace Elements", "people": "Gao, Yuan", "repository": "USAP-DC", "science_program": null, "title": "Concentrations and Particle Size Distributions of Aerosol Trace Elements", "url": "https://www.usap-dc.org/view/dataset/601370"}], "date_created": "Thu, 20 Feb 2020 00:00:00 GMT", "description": "The research seeks to further quantify the input of atmospheric Fe into the sparsely sampled Southern Ocean (SO), specifically in the vicinity of the West Antarctic Peninsula (WAP) and adjacent continental shelf waters in the Drake Passage. This is typically a high nutrient low chlorophyll region where surface trace metal and primary productivity data are suggestive of Fe limitation. The WAP is characterized by high productivity in the austral summer, and at this time may be in the path of northern dust (aeolian Fe) input or subject to melt influx of elevated Fe accumulated from glacial and present-day sea ice sources.\u003cbr/\u003e\u003cbr/\u003ePrimary scientific questions are: (1) to what extent does atmospheric Fe contribute to nutrient cycles and ecosystem dynamics in the SO? (2) How is warming climate occurring in the WAP affecting the aerosol composition of the maritime atmosphere. The primary productivity of the Southern Ocean is key to understanding oceanic uptake of anthropogenic greenhouse gases such as carbon dioxide.", "east": -64.05, "geometry": "POINT(-64.05 -64.77)", "instruments": null, "is_usap_dc": true, "keywords": "Aerosol Concentration; TRACE GASES/TRACE SPECIES; Particle Size; Palmer Station; FIELD INVESTIGATION; Trace Elements; Iron; AEROSOL OPTICAL DEPTH/THICKNESS; USAP-DC", "locations": "Palmer Station", "north": -64.77, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Gao, Yuan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.77, "title": "Quantifying Atmospheric Iron Properties over West Antarctic Peninsula", "uid": "p0010082", "west": -64.05}, {"awards": "1401489 Sigman, Daniel", "bounds_geometry": "POLYGON((-180 -45,-144 -45,-108 -45,-72 -45,-36 -45,0 -45,36 -45,72 -45,108 -45,144 -45,180 -45,180 -47.5,180 -50,180 -52.5,180 -55,180 -57.5,180 -60,180 -62.5,180 -65,180 -67.5,180 -70,144 -70,108 -70,72 -70,36 -70,0 -70,-36 -70,-72 -70,-108 -70,-144 -70,-180 -70,-180 -67.5,-180 -65,-180 -62.5,-180 -60,-180 -57.5,-180 -55,-180 -52.5,-180 -50,-180 -47.5,-180 -45))", "dataset_titles": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age; Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.; Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.; GOSHIP section IO8S and P18S", "datasets": [{"dataset_uid": "200048", "doi": "doi.pangaea.de/10.1594/PANGAEA.891436.", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound nitrogen isotope and opal flux records over the Holocene period in Southern Ocean sediment cores MD12-3396, MD11-3353 and PS75/072-4.", "url": "https://doi.pangaea.de/10.1594/PANGAEA.891436"}, {"dataset_uid": "200049", "doi": "doi.org/10.1594/PANGAEA.848271", "keywords": null, "people": null, "repository": "PANGAEA", "science_program": null, "title": "Diatom-bound N isotope records over the last two glacial cycles in sediment core PS75/072-4.", "url": "https://doi.org/10.1594/PANGAEA.848271"}, {"dataset_uid": "200050", "doi": "", "keywords": null, "people": null, "repository": "CLIVAR", "science_program": null, "title": "GOSHIP section IO8S and P18S", "url": "https://cchdo.ucsd.edu/"}, {"dataset_uid": "200051", "doi": "", "keywords": null, "people": null, "repository": "Publication", "science_program": null, "title": "Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age", "url": "https://www.pnas.org/content/suppl/2017/03/14/1615718114.DCSupplemental"}], "date_created": "Thu, 08 Aug 2019 00:00:00 GMT", "description": "ABSTRACT\u003cbr/\u003eIntellectual Merit:\u003cbr/\u003eThe high concentration of the major nutrients nitrate and phosphate is a fundamental characteristic of the Antarctic Zone in the Southern Ocean and is central to its role in global ocean fertility and the global carbon cycle. The isotopic composition of diatom-bound organic nitrogen is one of the best hopes for reconstructing the nutrient status of polar surface waters over glacial cycles, which in turn may hold the explanation for the decline in atmospheric carbon dioxide during ice ages. The PIs propose to generate detailed diatom-bound nitrogen isotope (\u0026#948;15Ndb) records from high sedimentation rate cores from the Kerguelen Plateau. Because the cores were collected at relatively shallow seafloor depths, they have adequate planktonic and benthic foraminifera to develop accurate age models. The resulting data could be compared with climate records from Antarctic ice cores and other archives to investigate climate-related changes, including the major steps into and out of ice ages and the millennial-scale events that occur during ice ages and at their ends. The records generated in this project will provide a critical test of hypotheses for the cause of lower ice age CO2.\u003cbr/\u003e\u003cbr/\u003eBroader impacts:\u003cbr/\u003eThis study will contribute to the goal of understanding ice ages and past CO2 changes, which both have broad implications for future climate. Undergraduates will undertake summer internships, with the possibility of extending their work into junior year projects and senior theses. In addition, the PI will lead modules for two Princeton programs for middle school teachers and will host a teacher for a six-week summer research project.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; South Pacific Ocean; USAP-DC; NOT APPLICABLE", "locations": "South Pacific Ocean", "north": -45.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Sigman, Daniel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "PANGAEA", "repositories": "CLIVAR; PANGAEA; Publication", "science_programs": null, "south": -70.0, "title": "High-resolution, Assemblage-specific Records of Diatom-bound N Isotopes from the Indian Sector of the Antarctic Ocean", "uid": "p0010046", "west": -180.0}, {"awards": "1443420 Dodd, Justin", "bounds_geometry": "POLYGON((167.07 -77.87,167.073 -77.87,167.076 -77.87,167.079 -77.87,167.082 -77.87,167.085 -77.87,167.088 -77.87,167.091 -77.87,167.094 -77.87,167.097 -77.87,167.1 -77.87,167.1 -77.873,167.1 -77.876,167.1 -77.879,167.1 -77.882,167.1 -77.885,167.1 -77.888,167.1 -77.891,167.1 -77.894,167.1 -77.897,167.1 -77.9,167.097 -77.9,167.094 -77.9,167.091 -77.9,167.088 -77.9,167.085 -77.9,167.082 -77.9,167.079 -77.9,167.076 -77.9,167.073 -77.9,167.07 -77.9,167.07 -77.897,167.07 -77.894,167.07 -77.891,167.07 -77.888,167.07 -77.885,167.07 -77.882,167.07 -77.879,167.07 -77.876,167.07 -77.873,167.07 -77.87))", "dataset_titles": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "datasets": [{"dataset_uid": "601220", "doi": "10.15784/601220", "keywords": "AND-1B; ANDRILL; Antarctica; Chemistry:Sediment; Cryosphere; Delta 18O; Diatom; Mass Spectrometer; Oxygen Isotopes; Paleoclimate; Pliocene; Sediment; WAIS; West Antarctic Ice Sheet", "people": "Abbott, Tirzah; Dodd, Justin", "repository": "USAP-DC", "science_program": "ANDRILL", "title": "Diatom Oxygen Isotope Evidence of Pliocene (~4.68 to 3.44 Ma) Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "url": "https://www.usap-dc.org/view/dataset/601220"}], "date_created": "Tue, 06 Aug 2019 00:00:00 GMT", "description": "Abstract\u003cbr/\u003eDuring the Early Pliocene, 4.8 to 3.4 million years ago, warmer-than-present global temperatures resulted in a retreat of the Ross Ice Shelf and West Antarctic Ice Sheet. Understanding changes in ocean dynamics during times of reduced ice volume and increased temperatures in the geologic past will improve the predictive models for these conditions. The primary goal of the proposed research is to develop a new oxygen isotope record of Pliocene oceanographic conditions near the Antarctic continent. Oxygen isotope values from the carbonate tests of benthic foraminifera have become the global standard for paleo-oceanographic studies, but foraminifera are sparse in high-latitude sediment cores. This research will instead make use of oxygen isotope measurements from diatom silica preserved in a marine sediment core from the Ross Sea. The project is the first attempt at using this method and will advance understanding of global ocean dynamics and ice sheet-ocean interactions during the Pliocene. The project will foster the professional development of two early-career scientists and serve as training for graduate and undergraduate student researchers. The PIs will use this project to introduce High School students to polar/oceanographic research, as well as stable isotope geochemistry. Collaboration with teachers via NSTA and Polar Educators International will ensure the implementation of excellent STEM learning activities and curricula for younger students. \u003cbr/\u003e\u003cbr/\u003eTechnical Description\u003cbr/\u003eThis project will produce a high-resolution oxygen isotope record from well-dated diatom rich sediments that have been cross-correlated with global benthic foraminifera oxygen isotope records. Diatom silica frustules deposited during the Early Pliocene and recovered by the ANDRILL Project (AND-1B) provide ideal material for this objective. Diatomite unites in the AND-1B core are nearly pure, with little evidence of opal formation. A diatom oxygen isotope record from this core offers the potential to constrain lingering uncertainties about Ross Sea and Southern Ocean paleoceanography and Antarctic Ice Sheet history during a time of high atmospheric carbon dioxide concentrations. Specifically, oxygen isotope variations will be used to constrain changes in the water temperature and/or freshwater flux in the Pliocene Ross Sea. Diatom species data from the AND-1B core have been used to infer variations in the extent and duration of seasonal sea ice coverage, sea surface temperatures, and mid-water advection onto the continental shelf. However, the diatom oxygen isotope record will provide the first direct measure of water/oxygen isotope values at the Antarctic continental margin during the Pliocene.", "east": 167.1, "geometry": "POINT(167.085 -77.885)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "OXYGEN ISOTOPES; USAP-DC; Antarctica; NOT APPLICABLE", "locations": "Antarctica", "north": -77.87, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Dodd, Justin; Scherer, Reed Paul; Warnock, Jonathan", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "ANDRILL", "south": -77.9, "title": "Diatom and Oxygen Isotope Evidence of Pliocene Antarctic Ice Sheet Dynamics and Ross Sea Paleoceanography", "uid": "p0010042", "west": 167.07}, {"awards": "1443550 Brook, Edward", "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": "Polar Ice Cores 3,000 Year Nitrous Oxide d15N and d18O Data; SPICEcore Holocene CO2 and N2O data", "datasets": [{"dataset_uid": "200055", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Polar Ice Cores 3,000 Year Nitrous Oxide d15N and d18O Data", "url": "https://www.ncdc.noaa.gov/paleo-search/study/25530"}, {"dataset_uid": "601197", "doi": "10.15784/601197", "keywords": "Antarctica; Carbon Dioxide; Cryosphere; Ice Core Gas Records; Nitrous Oxide; South Pole; SPICEcore", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SPICEcore Holocene CO2 and N2O data", "url": "https://www.usap-dc.org/view/dataset/601197"}], "date_created": "Tue, 06 Aug 2019 00:00:00 GMT", "description": "The temperature of the earth is controlled, in part, by heat trapping gases that include carbon dioxide, methane, and nitrous oxide. Despite their importance to climate, direct measurements of these gases in the atmosphere are limited to the last 50 years at best. Air trapped in ice cores extends those data back hundreds of millennia, and measurements of greenhouse gases in ice cores underpin much of our understanding of global chemical cycles relevant to modern climate change. Existing records vary in quality and detail. The proposed work fills gaps in our knowledge of nitrous oxide and carbon dioxide over the last 10,000 years. New measurements from an ice core from the South Pole will be used to determine what role changes in ocean and land based processes played in controlling these gases, which decreased during the first 2,000 years of this time period, then gradually increased toward the present. The work will address a major controversy over whether early human activities could have impacted the atmosphere, and provide data to improve mathematical models of the land-ocean-atmosphere system that predict how future climate change will impact the composition of the atmosphere and climate. \u003cbr/\u003e\u003cbr/\u003eFor nitrous oxide the work will improve on existing concentration records It will also develop measurement of the isotopomers of nitrous oxide and explore their utility for understanding aspects of the Holocene nitrous oxide budget. The primary goal is to determine if marine and/or terrestrial emissions of nitrous oxide change in response to changes in Holocene climate. A new Holocene isotopic record for carbon dioxide (stable carbon and oxygen isotopes), will improve the precision of existing records by a factor 5 and increase the temporal resolution. These data will be used to evaluate controversial hypotheses about why carbon dioxide concentrations changed in the Holocene and provide insight into millennial scale processes in the carbon cycle, which are not resolved by current isotopic data. A graduate student and post doc will receive advanced training during and the student and principle investigator will conduct outreach efforts targeted at local middle school students. The proposed work will also contribute to teaching efforts by the PI and to public lectures on climate and climate change. The results will be disseminated through publications, data archive, and the OSU Ice Core Lab web site. New analytical methods of wide utility will also be developed and documented.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Antarctica; ICE CORE RECORDS; CARBON DIOXIDE; NOT APPLICABLE; USAP-DC; TRACE GASES/TRACE SPECIES; NITROUS OXIDE", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Brook, Edward J.", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCEI", "repositories": "NCEI; USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Controls on Variations in Atmospheric Carbon Dioxide and Nitrous Oxide During the Last 10,000 years", "uid": "p0010043", "west": -180.0}, {"awards": "1341513 Maksym, Edward; 1341725 Guest, Peter; 1341606 Stammerjohn, Sharon; 1543483 Sedwick, Peter; 1341717 Ackley, Stephen", "bounds_geometry": "POLYGON((-180 -55,-177 -55,-174 -55,-171 -55,-168 -55,-165 -55,-162 -55,-159 -55,-156 -55,-153 -55,-150 -55,-150 -57.3,-150 -59.6,-150 -61.9,-150 -64.2,-150 -66.5,-150 -68.8,-150 -71.1,-150 -73.4,-150 -75.7,-150 -78,-153 -78,-156 -78,-159 -78,-162 -78,-165 -78,-168 -78,-171 -78,-174 -78,-177 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -75.7,160 -73.4,160 -71.1,160 -68.8,160 -66.5,160 -64.2,160 -61.9,160 -59.6,160 -57.3,160 -55,162 -55,164 -55,166 -55,168 -55,170 -55,172 -55,174 -55,176 -55,178 -55,-180 -55))", "dataset_titles": "ASPeCt Visual Ice Observations on PIPERS Cruise NBP1704 April-June 2017; Expedition data of NBP1704; Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle; NBP1704 CTD sensor data; NBP1704 Expedition Data; PIPERS airborne lidar; PIPERS lidar data; PIPERS Meteorology Rawinsonde Data; PIPERS Meteorology Time Series; PIPERS Noble Gases; Sea Ice Layer Cakes, PIPERS 2017; SUMO unmanned aerial system (UAS) atmospheric data", "datasets": [{"dataset_uid": "200101", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "PIPERS lidar data", "url": "http://wonder.ldeo.columbia.edu/data/publicationData/PIPERS/"}, {"dataset_uid": "001363", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1704 Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1704"}, {"dataset_uid": "601609", "doi": "10.15784/601609", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Mass Spectrometer; NBP1704; Noble Gas; Oceans; Ross Sea; R/V Nathaniel B. Palmer", "people": "Loose, Brice", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Noble Gases", "url": "https://www.usap-dc.org/view/dataset/601609"}, {"dataset_uid": "601207", "doi": "10.15784/601207", "keywords": "Antarctica; Cryosphere; Digital Elevation Model (DEM); Glaciology; Ice; Ice Thickness; Ice Thickness Distribution; LIDAR; NBP1704; PIPERS; Ross Sea; R/V Nathaniel B. Palmer; Sea Ice; Snow; Snow Depth; Surface Elevation", "people": "Maksym, Edward; Mei, M. Jeffrey; Jeffrey Mei, M.", "repository": "USAP-DC", "science_program": null, "title": "Sea Ice Layer Cakes, PIPERS 2017", "url": "https://www.usap-dc.org/view/dataset/601207"}, {"dataset_uid": "200150", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Impact of Convective Processes and Sea Ice Formation on the Distribution of Iron in the Ross Sea: Closing the Seasonal Cycle", "url": "https://www.bco-dmo.org/project/815403"}, {"dataset_uid": "002663", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1704", "url": "https://www.rvdata.us/search/cruise/NBP1704"}, {"dataset_uid": "601191", "doi": "10.15784/601191", "keywords": "Air Temperature; Antarctica; Atmosphere; Cryosphere; Meteorology; NBP1704; PIPERS; R/V Nathaniel B. Palmer; Southern Ocean; Temperature Profiles; UAV; Unmanned Aircraft", "people": "Cassano, John", "repository": "USAP-DC", "science_program": null, "title": "SUMO unmanned aerial system (UAS) atmospheric data", "url": "https://www.usap-dc.org/view/dataset/601191"}, {"dataset_uid": "601188", "doi": "", "keywords": "Aerogeophysics; Airborne Laser Altimetry; Antarctica; Cryosphere; LIDAR; PIPERS; Ross Sea; Sea Ice", "people": "Bell, Robin", "repository": "USAP-DC", "science_program": null, "title": "PIPERS airborne lidar", "url": "https://www.usap-dc.org/view/dataset/601188"}, {"dataset_uid": "601185", "doi": "10.15784/601185 ", "keywords": "Air Temperature; Antarctica; Atmosphere; Atmospheric Surface Winds; Cryosphere; Meteorology; NBP1704; PIPERS; Pressure; Radiosonde ; Rawinsonde ; Relative Humidity; Ross Sea; R/V Nathaniel B. Palmer; Wind Direction; Wind Speed", "people": "Guest, Peter", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Meteorology Rawinsonde Data", "url": "https://www.usap-dc.org/view/dataset/601185"}, {"dataset_uid": "601184", "doi": "10.15784/601184 ", "keywords": "Air Temperature; Antarctica; Atmosphere; Cryosphere; Meteorology; Near-surface Air Temperatures; PIPERS; Radiation; Sea Ice Temperatures; Temperature; Weather Station Data; Wind Direction; Wind Speed", "people": "Guest, Peter", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Meteorology Time Series", "url": "https://www.usap-dc.org/view/dataset/601184"}, {"dataset_uid": "601183", "doi": "10.15784/601183", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Concentration; Ice Thickness; Ice Type; NBP1704; Oceans; Ross Sea; R/V Nathaniel B. Palmer; Sea Ice; Snow Depth; Snow Depth; Snow/Ice; Visual Observations", "people": "Ackley, Stephen", "repository": "USAP-DC", "science_program": null, "title": "ASPeCt Visual Ice Observations on PIPERS Cruise NBP1704 April-June 2017", "url": "https://www.usap-dc.org/view/dataset/601183"}, {"dataset_uid": "601422", "doi": "10.15784/601422", "keywords": "Antarctica; Cryosphere; CTD; CTD Data; NBP1704; Ocean Profile Data; Ross Sea; R/V Nathaniel B. Palmer; Salinity; Temperature", "people": "Stammerjohn, Sharon", "repository": "USAP-DC", "science_program": null, "title": "NBP1704 CTD sensor data", "url": "https://www.usap-dc.org/view/dataset/601422"}], "date_created": "Mon, 10 Jun 2019 00:00:00 GMT", "description": "The one place on Earth consistently showing increases in sea ice area, duration, and concentration is the Ross Sea in Antarctica. Satellite imagery shows about half of the Ross Sea increases are associated with changes in the austral fall, when the new sea ice is forming. The most pronounced changes are also located near polynyas, which are areas of open ocean surrounded by sea ice. To understand the processes driving the sea ice increase, and to determine if the increase in sea ice area is also accompanied by a change in ice thickness, this project will conduct an oceanographic cruise to the polynyas of the Ross Sea in April and May, 2017, which is the austral fall. The team will deploy state of the art research tools including unmanned airborne systems (UASs, commonly called drones), autonomous underwater vehicles (AUVs), and remotely operated underwater vehicles (ROVs). Using these tools and others, the team will study atmospheric, oceanic, and sea ice properties and processes concurrently. A change in sea ice production will necessarily change the ocean water below, which may have significant consequences for global ocean circulation patterns, a topic of international importance. All the involved institutions will be training students, and all share the goal of expanding climate literacy in the US, emphasizing the role high latitudes play in the Earth\u0027s dynamic climate.\u003cbr/\u003e\u003cbr/\u003eThe main goal of the project is to improve estimates of sea ice production and water mass transformation in the Ross Sea. The team will fully capture the spatial and temporal changes in air-ice-ocean interactions when they are initiated in the austral fall, and then track the changes into the winter and spring using ice buoys, and airborne mapping with the newly commissioned IcePod instrument system, which is deployed on the US Antarctic Program\u0027s LC-130 fleet. The oceanographic cruise will include stations in and outside of both the Terra Nova Bay and Ross Ice Shelf polynyas. Measurements to be made include air-sea boundary layer fluxes of heat, freshwater, and trace gases, radiation, and meteorology in the air; ice formation processes, ice thickness, snow depth, mass balance, and ice drift within the sea ice zone; and temperature, salinity, and momentum in the ocean below. Following collection of the field data, the team will improve both model parameterizations of air-sea-ice interactions and remote sensing algorithms. Model parameterizations are needed to determine if sea-ice production has increased in crucial areas, and if so, why (e.g., stronger winds or fresher oceans). The remote sensing validation will facilitate change detection over wider areas and verify model predictions over time. Accordingly this project will contribute to the international Southern Ocean Observing System (SOOS) goal of measuring essential climate variables continuously to monitor the state of the ocean and ice cover into the future.", "east": -150.0, "geometry": "POINT(-175 -66.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LIDAR; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN MIXED LAYER; TRACE ELEMENTS; CARBON DIOXIDE; ATMOSPHERIC RADIATION; ICE GROWTH/MELT; AMD; BOUNDARY LAYER TEMPERATURE; SULFUR COMPOUNDS; NBP1704; HEAT FLUX; ICE DEPTH/THICKNESS; R/V NBP; USA/NSF; BOUNDARY LAYER WINDS; SNOW DEPTH; VERTICAL PROFILES; AMD/US; METHANE; POLYNYAS; CONDUCTIVITY; SEA ICE; Ross Sea; WATER MASSES; TURBULENCE; USAP-DC", "locations": "Ross Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Instrumentation and Support; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Ackley, Stephen; Bell, Robin; Weissling, Blake; Xie , Hongjie; Nuss, Wendell; Maksym, Edward; Stammerjohn, Sharon; Cassano, John; Guest, Peter; Sedwick, Peter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "PI website", "repositories": "BCO-DMO; PI website; R2R; USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Seasonal Sea Ice Production in the Ross Sea, Antarctica", "uid": "p0010032", "west": 160.0}, {"awards": "1443710 Severinghaus, Jeffrey; 1443464 Sowers, Todd; 1443472 Brook, Edward", "bounds_geometry": "POINT(0 -90)", "dataset_titles": "South Pole CH4 data for termination; South Pole Ice Core Isotopes of N2 and Ar; South Pole ice core (SPC14) discrete methane data; South Pole ice core total air content; South Pole (SPICECORE) 15N, 18O, O2/N2 and Ar/N2; SP19 Gas Chronology", "datasets": [{"dataset_uid": "601230", "doi": "10.15784/601230", "keywords": "Antarctica; Atmospheric CH4; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Data; Methane; Methane Concentration; Snow/Ice; South Pole; SPICEcore", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole CH4 data for termination", "url": "https://www.usap-dc.org/view/dataset/601230"}, {"dataset_uid": "601381", "doi": "10.15784/601381", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Methane; South Pole; SPICEcore", "people": "Winski, Dominic A.; Kennedy, Joshua A.; Ferris, David G.; Kalk, Michael; Severinghaus, Jeffrey P.; Hood, Ekaterina; Fudge, T. J.; Steig, Eric J.; Osterberg, Erich; Epifanio, Jenna; Brook, Edward J.; Buizert, Christo; Kreutz, Karl; Aydin, Murat; Edwards, Jon S.; Sowers, Todd A.; Kahle, Emma", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core (SPC14) discrete methane data", "url": "https://www.usap-dc.org/view/dataset/601381"}, {"dataset_uid": "601380", "doi": "10.15784/601380", "keywords": "Antarctica; CH4; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ice Core Stratigraphy; Methane; South Pole; SPICEcore", "people": "Epifanio, Jenna", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "SP19 Gas Chronology", "url": "https://www.usap-dc.org/view/dataset/601380"}, {"dataset_uid": "601517", "doi": "10.15784/601517", "keywords": "Antarctica; Argon; Argon Isotopes; Cryosphere; Firn; Firn Temperature Gradient; Firn Thickness; Gas Isotopes; Gas Isotopes; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Nitrogen; Nitrogen Isotopes; South Pole; SPICEcore", "people": "Morgan, Jacob; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole Ice Core Isotopes of N2 and Ar", "url": "https://www.usap-dc.org/view/dataset/601517"}, {"dataset_uid": "601231", "doi": "10.15784/601231", "keywords": "Air Content; Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Records; Snow/Ice; South Pole; SPICEcore", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole ice core total air content", "url": "https://www.usap-dc.org/view/dataset/601231"}, {"dataset_uid": "601152", "doi": "10.15784/601152", "keywords": "Antarctica; Antarctic Ice Sheet; Chemistry:Gas; Chemistry:Ice; Cryosphere; Delta 18O; Dole Effect; Firn Thickness; Gas Isotopes; Geochemistry; Glaciers/Ice Sheet; Glaciology; Gravitational Settling; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; Inert Gases; Nitrogen; Nitrogen Isotopes; Oxygen; Oxygen Isotopes; Snow/Ice; South Pole; SPICECORE", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": "SPICEcore", "title": "South Pole (SPICECORE) 15N, 18O, O2/N2 and Ar/N2", "url": "https://www.usap-dc.org/view/dataset/601152"}], "date_created": "Sat, 02 Feb 2019 00:00:00 GMT", "description": "Gases trapped in ice cores have revealed astonishing things about the greenhouse gas composition of the past atmosphere, including the fact that carbon dioxide concentrations never rose above 300 parts per million during the last 800,000 years. This places today\u0027s concentration of 400 parts per million in stark contrast. Furthermore, these gas records show that natural sources of greenhouse gas such as oceans and ecosystems act as amplifiers of climate change by increasing emissions of gases during warmer periods. Such amplification is expected to occur in the future, adding to the human-produced gas burden. The South Pole ice core will build upon these prior findings by expanding the suite of gases to include, for the first time, those potent trace gases that both trapped heat and depleted ozone during the past 40,000 years. The present project on inert gases and methane in the South Pole ice core will improve the dating of this crucial record, to unprecedented precision, so that the relative timing of events can be used to learn about the mechanism of trace gas production and destruction, and consequent climate change amplification. Ultimately, this information will inform predictions of future atmospheric chemical cleansing mechanisms and climate in the context of our rapidly changing atmosphere. This award also engages young people in the excitement of discovery and polar research, helping to entrain the next generations of scientists and educators. Education of graduate students, a young researcher (Buizert), and training of technicians, will add to the nation?s human resource base. \u003cbr/\u003e \u003cbr/\u003eThis award funds the construction of the gas chronology for the South Pole 1500m ice core, using measured inert gases (d15N and d40Ar--Nitrogen and Argon isotope ratios, respectively) and methane in combination with a next-generation firn densification model that treats the stochastic nature of air trapping and the role of impurities on densification. The project addresses fundamental gaps in scientific understanding that limit the accuracy of gas chronologies, specifically a poor knowledge of the controls on ice-core d15N and the possible role of layering and impurities in firn densification. These gaps will be addressed by studying the gas enclosure process in modern firn at the deep core site. The work will comprise the first-ever firn air pumping experiment that has tightly co-located measurements of firn structural properties on the core taken from the same borehole.\u003cbr/\u003e\u003cbr/\u003eThe project will test the hypothesis that the lock-in horizon as defined by firn air d15N, CO2, and methane is structurally controlled by impermeable layers, which are in turn created by high-impurity content horizons in which densification is enhanced. Thermal signals will be sought using the inert gas measurements, which improve the temperature record with benefits to the firn densification modeling. Neon, argon, and oxygen will be measured in firn air and a limited number of deep core samples to test whether glacial period layering was enhanced, which could explain low observed d15N in the last glacial period. Drawing on separate volcanic and methane synchronization to well-dated ice cores to create independent ice and gas tie points, independent empirical estimates of the gas age-ice age difference will be made to check the validity of the firn densification model-inert gas approach to calculating the gas age-ice age difference. These points will also be used to test whether the anomalously low d15N seen during the last glacial period in east Antarctic ice cores is due to deep air convection in the firn, or a missing impurity dependence in the firn densification models. \u003cbr/\u003e\u003cbr/\u003eThe increased physical understanding gained from these studies, combined with new high-precision measurements, will lead to improved accuracy of the gas chronology of the South Pole ice core, which will enhance the overall science return from this gas-oriented core. This will lead to clarification of timing of atmospheric gas variations and temperature, and aid in efforts to understand the biogeochemical feedbacks among trace gases. These feedbacks bear on the future response of the Earth System to anthropogenic forcing. Ozone-depleting substances will be measured in the South Pole ice core record, and a precise gas chronology will add value. Lastly, by seeking a better understanding of the physics of gas entrapment, the project aims to have an impact on ice-core science in general.", "east": 0.0, "geometry": "POINT(0 -90)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "AMD/US; USAP-DC; AMD; LABORATORY; Antarctica; NITROGEN ISOTOPES; USA/NSF; METHANE; FIELD INVESTIGATION", "locations": "Antarctica", "north": -90.0, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Sowers, Todd A.; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Collaborative Research: Inert Gas and Methane Based Climate Records throughout the South Pole Deep Ice Core", "uid": "p0010005", "west": 0.0}, {"awards": "1443306 Mayewski, Paul; 1443263 Higgins, John", "bounds_geometry": null, "dataset_titles": "Carbon dioxide concentration and its stable carbon isotope composition in Allan Hills ice cores; Elemental and isotopic composition of heavy noble gases in Allan Hills ice cores; Elemental and isotopic composition of nitrogen, oxygen, and argon in Allan Hills ice cores; Greenhouse gas composition in the Allan Hills S27 ice core; Methane concentration in Allan Hills ice cores; Stable isotope composition of the trapped air in the Allan Hills S27 ice core; Stable water isotope data for the AH-1502 ice core drilled at the Allan Hills Blue ice area; Stable water isotope data for the AH-1503 ice core drilled at the Allan Hills Blue ice area; Stable water isotope data for the surface samples collected at the Allan Hills Blue ice area", "datasets": [{"dataset_uid": "601425", "doi": "10.15784/601425", "keywords": "Allan Hills; Antarctica; Blue Ice; Carbon Dioxide; Cryosphere; Ice Core; Methane", "people": "Yan, Yuzhen; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Greenhouse gas composition in the Allan Hills S27 ice core", "url": "https://www.usap-dc.org/view/dataset/601425"}, {"dataset_uid": "601201", "doi": "10.15784/601201", "keywords": "Allan Hills; Allan Hills project; Antarctica; Argon; Chemistry:Ice; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Data; Ice Core Gas Records; Krypton; Mass Spectrometer; Noble Gas; Snow/Ice; Xenon", "people": "Yan, Yuzhen; Severinghaus, Jeffrey P.; Ng, Jessica; Higgins, John; Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Elemental and isotopic composition of heavy noble gases in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601201"}, {"dataset_uid": "601483", "doi": "10.15784/601483", "keywords": "AGDC-project; Allan Hills; Antarctica; Argon; Cryosphere; Ice; Ice Core Data; Ice Core Gas Records; Isotope; Mass Spectrometry; Nitrogen; Oxygen", "people": "Yan, Yuzhen; Bender, Michael; Higgins, John", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Elemental and isotopic composition of nitrogen, oxygen, and argon in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601483"}, {"dataset_uid": "601130", "doi": "10.15784/601130", "keywords": "Allan Hills; Allan Hills project; Antarctica; Blue Ice Area; Chemistry:Ice; Cryosphere; Delta 18O; Delta Deuterium; Glaciers/Ice Sheet; Glaciology; Ice Core Gas Records; Ice Core Records; Oxygen; Snow/Ice; Stable water isotopes; Transantarctic Mountains", "people": "Kurbatov, Andrei V.; Yan, Yuzhen; Introne, Douglas; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the surface samples collected at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601130"}, {"dataset_uid": "601129", "doi": "10.15784/601129", "keywords": "Allan Hills; Allan Hills project; Antarctica; Blue Ice Area; Cryosphere; Delta 18O; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Chemistry; Ice Core Records; isotope data; Oxygen; Snow/Ice; Stable water isotopes; Transantarctic Mountains", "people": "Kurbatov, Andrei V.; Mayewski, Paul A.; Introne, Douglas; Yan, Yuzhen", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the AH-1502 ice core drilled at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601129"}, {"dataset_uid": "601128", "doi": "10.15784/601128", "keywords": "Allan Hills; Antarctica; Blue Ice Area; Chemistry:Ice; Cryosphere; Delta 18O; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope record; Mass Spectrometry; Stable water isotopes", "people": "Kurbatov, Andrei V.; Yan, Yuzhen; Introne, Douglas; Mayewski, Paul A.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable water isotope data for the AH-1503 ice core drilled at the Allan Hills Blue ice area", "url": "https://www.usap-dc.org/view/dataset/601128"}, {"dataset_uid": "601512", "doi": "10.15784/601512", "keywords": "Allan Hills; Antarctica; Blue Ice; Cryosphere; Ice Core; Ice Core Gas Records; Isotope; Nitrogen; Oxygen", "people": "Bender, Michael; Higgins, John; Yan, Yuzhen", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Stable isotope composition of the trapped air in the Allan Hills S27 ice core", "url": "https://www.usap-dc.org/view/dataset/601512"}, {"dataset_uid": "601203", "doi": "10.15784/601203", "keywords": "Allan Hills; Allan Hills project; Antarctica; Chemistry:Ice; Cryosphere; Gas Chromatography; Glaciers/Ice Sheet; Glaciology; Greenhouse Gases; Ice; Ice Core Data; Ice Core Gas Records; Methane; Snow/Ice", "people": "Brook, Edward J.; Yan, Yuzhen; Higgins, John; Bender, Michael", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Methane concentration in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601203"}, {"dataset_uid": "601202", "doi": "10.15784/601202", "keywords": "Allan Hills; Allan Hills project; Antarctica; Carbon Dioxide; Carbon Isotopes; Chemistry:Ice; CO2; Cryosphere; Gas Chromatography; Glaciers/Ice Sheet; Glaciology; Greenhouse Gases; Ice; Ice Core Data; Ice Core Gas Records; Ice Core Records; Mass Spectrometer; Mass Spectrometry; Methane; Snow/Ice", "people": "Higgins, John; Yan, Yuzhen; Bender, Michael; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Carbon dioxide concentration and its stable carbon isotope composition in Allan Hills ice cores", "url": "https://www.usap-dc.org/view/dataset/601202"}], "date_created": "Thu, 18 Oct 2018 00:00:00 GMT", "description": "Bubbles of ancient air trapped in ice cores permit the direct reconstruction of atmospheric composition and allow us to link greenhouse gases and global climate over the last 800,000 years. Previous field expeditions to the Allan Hills blue ice area, Antarctica, have recovered ice cores that date to one million years, the oldest ice cores yet recovered from Antarctica. These records have revealed that interglacial CO2 concentrations decreased by 800,000 years ago and that, in the warmer world 1 million years ago, CO2 and Antarctic temperature were linked as during the last 800,000 years. This project will return to the Allan Hills blue ice area to recover additional ice cores that date to 1 million years or older. The climate records developed from the drilled ice cores will provide new insights into the chemical composition of the atmosphere and Antarctic climate during times of comparable or even greater warmth than the present day. Our results will help answer questions about issues associated with anthropogenic change. These include the relationship between temperature change and the mass balance of Antarctic ice; precipitation and aridity variations associated with radiatively forced climate change; and the climate significance of sea ice extent. The project will entrain two graduate students and a postdoctoral scholar, and will conduct outreach including workshops to engage teachers in carbon science and ice cores.\u003cbr/\u003e\u003cbr/\u003eBetween about 2.8-0.9 million years ago, Earth\u0027s climate was characterized by 40,000-year cycles, driven or paced by changes in the tilt of Earth\u0027s spin axis. Much is known about the \"40,000-year\" world from studies of deep-sea sediments, but our understanding of climate change during this period is incomplete because we lack records of Antarctic climate and direct records of atmospheric greenhouse gas concentrations. We propose to address these issues by building on our recent studies of ancient ice from the Main Ice Field, Allan Hills, Antarctica. During previous field seasons we recovered ice extending, discontinuously, from 0.1-1.0 million years old. Ice was dated by measuring the 40Ar/38Ar (Argon) ratio of the trapped gases. Our discovery of million year-old ice demonstrates that there is gas-record-quality ice from the 40,000-year world in the Allan Hills Main Ice Field. We have identified two different sites, each overlying bedrock at ~ 200 m depth, that are attractive targets for coring ice dating to 1 million years and older. This project aims to core the ice at these two sites, re-occupy a previous site with million year-old ice and drill it down to the bedrock, and generate 10-20 short (~10-meter) cores in areas where our previous work and terrestrial meteorite ages suggest ancient surface ice. We plan to date the ice using the 40Ar/38Ar ages of trapped Argon. We also plan to characterize the continuity of our cores by measuring the deuterium and oxygen isotope ratios in the ice, methane, ratios of Oxygen and Argon to Nitrogen in trapped gas, the Nitrogen-15 isotope (d15N) of Nitrogen, and the Oxygen-18 isotope (d18O) of Oxygen. As the ice may be stratigraphically disturbed, these measurements will provide diagnostic properties for assessing the continuity of the ice-core records. Successful retrieval of ice older than one million years will provide the opportunity for follow-up work to measure the CO2 concentration and other properties within the ice to inform on the temperature history of the Allan Hills region, dust sources and source-area aridity, moisture sources, densification conditions, global average ocean temperature, and greenhouse gas concentrations. We will analyze the data in the context of leading hypotheses of the 40,000-year world and the Mid-Pleistocene Transition to the 100,000-year world. We expect to advance understanding of climate dynamics during these periods.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "AMD; Allan Hills; ice cores; AMD/US; USA/NSF; FIELD INVESTIGATION; USAP-DC; LABORATORY", "locations": "Allan Hills", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Mayewski, Paul A.; Kurbatov, Andrei V.; Higgins, John; Bender, Michael", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Allan Hills", "south": null, "title": "Collaborative Research: Window into the World with 40,000-year Glacial Cycles from Climate Records in Million Year-old Ice from the Allan Hills Blue Ice Area", "uid": "p0000760", "west": null}, {"awards": "1246293 Saba, Grace", "bounds_geometry": null, "dataset_titles": "2014 Antarctic krill growth experiment - submitted", "datasets": [{"dataset_uid": "002572", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "2014 Antarctic krill growth experiment - submitted", "url": "https://www.bco-dmo.org/project/721363"}], "date_created": "Fri, 14 Sep 2018 00:00:00 GMT", "description": "Climate change projections for this century suggest that the Southern Ocean will be the first region to be affected by seawater chemistry changes associated with enhanced carbon dioxide (CO2). Additionally, regions of the Southern Ocean are warming faster than any other locations on the planet. Ocean acidification and warming may act synergistically to impair the performance of different organisms by simultaneously increasing metabolic needs and reducing oxygen transport. However, no studies have measured krill acid-base regulation, metabolism, growth, or reproduction in the context of ocean acidification or synergistic \u0027greenhouse\u0027 conditions of elevated CO2 and temperature. In the present project, the investigators will conduct both short and prolonged exposure experiments at Palmer Station, Antarctica to determine the responses of Euphausia superba to elevated CO2 and temperature. The investigators will test hypotheses related to acid-base compensation and acclimation of various life stages of krill to elevated CO2 and temperature. Furthermore, they will determine these impacts on feeding, respiration, metabolism, growth, and reproduction.\u003cbr/\u003e\u003cbr/\u003eThe Antarctic krill, Euphausia superba, is a key component of Antarctic food webs as they are a primary food source for many of the top predators in the Southern Ocean including baleen whales, seals, penguins, and other sea birds. This project will determine the responses of Antarctic krill exposed to elevated CO2 and temperature and whether or not krill have the capacity to fully compensate under future ocean conditions. The proposed field effort will be complemented by an extensive broader impact effort focused on bringing marine science to both rural and urban high school students in the Midwest (Kansas). The core educational objectives of this proposal are to 1) instruct students about potential careers in marine science, 2) engage students and promote their interest in the scientific process, critical thinking, and applications of science, mathematics, and technology, and 3) and increase student and teacher awareness and understanding of the oceans and global climate change, with special focus on the Western Antarctic Peninsula region. Finally, this project will engage undergraduate and graduate students in the production, analysis, presentation and publication of datasets.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; NOT APPLICABLE", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Saba, Grace", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": null, "title": "Collaborative Research: Synergistic effects of Elevated Carbon Dioxide (CO2) and Temperature on the Metabolism, Growth, and Reproduction of Antarctic Krill (Euphausia Superba)", "uid": "p0000700", "west": null}, {"awards": "1443474 Jenkins, Bethany", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1608", "datasets": [{"dataset_uid": "002664", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1608", "url": "https://www.rvdata.us/search/cruise/NBP1608"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "This project focuses on an important group of photosynthetic algae in the Southern Ocean (SO), diatoms, and the roles associated bacterial communities play in modulating their growth. Diatom growth fuels the SO food web and balances atmospheric carbon dioxide by sequestering the carbon used for growth to the deep ocean on long time scales as cells sink below the surface. The diatom growth is limited by the available iron in the seawater, most of which is not freely available to the diatoms but instead is tightly bound to other compounds. The nature of these compounds and how phytoplankton acquire iron from them is critical to understanding productivity in this region and globally. The investigators will conduct experiments to characterize the relationship between diatoms, their associated bacteria, and iron in open ocean and inshore waters. Experiments will involve supplying nutrients at varying nutrient ratios to natural phytoplankton assemblages to determine how diatoms and their associated bacteria respond to different conditions. This will provide valuable data that can be used by climate and food web modelers and it will help us better understand the relationship between iron, a key nutrient in the ocean, and the organisms at the base of the food web that use iron for photosynthetic growth and carbon uptake. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. The project supports early career senior investigators and the training of graduate and undergraduate students as well as outreach activities with middle school Girl Scouts in Rhode Island, inner city middle and high school age girls in Virginia, and middle school girls in Florida.\u003cbr/\u003e\u003cbr/\u003eThe project combines trace metal biogeochemistry, phytoplankton cultivation, and molecular biology to address questions regarding the production of iron-binding compounds and the role of diatom-bacterial interactions in this iron-limited region. Iron is an essential micronutrient for marine phytoplankton. Phytoplankton growth in the SO is limited by a lack of sufficient iron, with important consequences for carbon cycling and climate in this high latitude regime. Some of the major outstanding questions in iron biogeochemistry relate to the organic compounds that bind \u003e99.9% of dissolved iron in surface oceans. The investigators\u0027 prior research in this region suggests that production of strong iron-binding compounds in the SO is linked to diatom blooms in waters with high nitrate to iron ratios. The sources of these compounds are unknown but the investigators hypothesize that they may be from bacteria, which are known to produce such compounds for their own use. The project will test three hypotheses concerning the production of these iron-binding compounds, limitations on the biological availability of iron even if present in high concentrations, and the roles of diatom-associated bacteria in these processes. Results from this project will provide fundamental information about the biogeochemical trigger, and biological sources and function, of natural strong iron-binding compound production in the SO, where iron plays a critical role in phytoplankton productivity, carbon cycling, and climate regulation.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP; NBP1608", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Jenkins, Bethany", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Investigating Iron-inding Ligands in Southern Ocean Diatom Communities: The Role of Diatom-Bacteria Associations", "uid": "p0000852", "west": null}, {"awards": "1543380 Shadwick, Elizabeth", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG1704", "datasets": [{"dataset_uid": "002732", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1704", "url": "https://www.rvdata.us/search/cruise/LMG1704"}, {"dataset_uid": "001364", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG1704"}], "date_created": "Fri, 29 Dec 2017 00:00:00 GMT", "description": "Interest in the reduced alkalinity of high latitude waters under conditions of enhanced CO2 uptake from the atmosphere have been the impetus of numerous recent studies of bio-stressors in the polar marine environment. The project seeks to improve our understanding of the variance of coastal Southern Ocean carbonate species (CO2 system), its diurnal and inter-annual variability, by acquiring autonomous, high frequency observations from an Antarctic coastal mooring(s). \u003cbr/\u003e\u003cbr/\u003eA moored observing system co-located within the existing Palmer LTER array will measure pH, CO2 partial pressure, temperature, salinity and dissolved oxygen with 3-hour frequency in this region of the West Antarctic Peninsula continental shelf. Such observations will help estimate the dominant physical and biological controls on the seasonal variations in the CO2 system in coastal Antarctic waters, including the sign, seasonality and the flux of the net annual air-sea exchange of carbon dioxide. The Palmer LTER site is experiencing rapid ecological change in the West Antarctic Peninsula, a region that is warming at rates faster than any other region of coastal Antarctica.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e XBT; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V LMG; LMG1704", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Shadwick, Elizabeth; Shadwick, Elizabeth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Resolving CO2 System Seasonality in the West Antarctic Peninsula with Autonomous Observations", "uid": "p0000875", "west": null}, {"awards": "1043471 Kaplan, Michael", "bounds_geometry": "POLYGON((-112.5 -79.468,-112.4586 -79.468,-112.4172 -79.468,-112.3758 -79.468,-112.3344 -79.468,-112.293 -79.468,-112.2516 -79.468,-112.2102 -79.468,-112.1688 -79.468,-112.1274 -79.468,-112.086 -79.468,-112.086 -79.4712,-112.086 -79.4744,-112.086 -79.4776,-112.086 -79.4808,-112.086 -79.484,-112.086 -79.4872,-112.086 -79.4904,-112.086 -79.4936,-112.086 -79.4968,-112.086 -79.5,-112.1274 -79.5,-112.1688 -79.5,-112.2102 -79.5,-112.2516 -79.5,-112.293 -79.5,-112.3344 -79.5,-112.3758 -79.5,-112.4172 -79.5,-112.4586 -79.5,-112.5 -79.5,-112.5 -79.4968,-112.5 -79.4936,-112.5 -79.4904,-112.5 -79.4872,-112.5 -79.484,-112.5 -79.4808,-112.5 -79.4776,-112.5 -79.4744,-112.5 -79.4712,-112.5 -79.468))", "dataset_titles": "List of samples of WAIS Divide and Byrd (deep) ice that were analyzed for radiogenic isotopes at LDEO", "datasets": [{"dataset_uid": "601065", "doi": "10.15784/601065", "keywords": "Antarctica; Cryosphere; Dust; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Sample/Collection Description; WAIS divide; WAIS Divide Ice Core", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "List of samples of WAIS Divide and Byrd (deep) ice that were analyzed for radiogenic isotopes at LDEO", "url": "https://www.usap-dc.org/view/dataset/601065"}], "date_created": "Sun, 29 Oct 2017 00:00:00 GMT", "description": "This award supports a project to obtain the first set of isotopic-based provenance data from the WAIS divide ice core. A lack of data from the WAIS prevents even a basic knowledge of whether different sources of dust blew around the Pacific and Atlantic sectors of the southern latitudes. Precise isotopic measurements on dust in the new WAIS ice divide core are specifically warranted because the data will be synergistically integrated with other high frequency proxies, such as dust concentration and flux, and carbon dioxide, for example. Higher resolution proxies will bridge gaps between our observations on the same well-dated, well-preserved core. The intellectual merit of the project is that the proposed analyses will contribute to the WAIS Divide Project science themes. Whether an active driver or passive recorder, dust is one of the most important but least understood components of regional and global climate. Collaborative and expert discussion with dust-climate modelers will lead to an important progression in understanding of dust and past atmospheric circulation patterns and climate around the southern latitudes, and help to exclude unlikely air trajectories to the ice sheets. The project will provide data to help evaluate models that simulate the dust patterns and cycle and the relative importance of changes in the sources, air trajectories and transport processes, and deposition to the ice sheet under different climate states. The results will be of broad interest to a range of disciplines beyond those directly associated with the WAIS ice core project, including the paleoceanography and dust- paleoclimatology communities. The broader impacts of the project include infrastructure and professional development, as the proposed research will initiate collaborations between LDEO and other WAIS scientists and modelers with expertise in climate and dust. Most of the researchers are still in the early phase of their careers and hence the project will facilitate long-term relationships. This includes a graduate student from UMaine, an undergraduate student from Columbia University who will be involved in lab work, in addition to a LDEO Postdoctoral scientist, and possibly an additional student involved in the international project PIRE-ICETRICS. The proposed research will broaden the scientific outlooks of three PIs, who come to Antarctic ice core science from a variety of other terrestrial and marine geology perspectives. Outreach activities include interaction with the science writers of the Columbia\u0027s Earth Institute for news releases and associated blog websites, public speaking, and involvement in an arts/science initiative between New York City\u0027s arts and science communities to bridge the gap between scientific knowledge and public perception.", "east": -112.086, "geometry": "POINT(-112.293 -79.484)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.468, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kaplan, Michael; Winckler, Gisela; Goldstein, Steven L.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.5, "title": "A Study of Atmospheric Dust in the WAIS Divide Ice Core Based on Sr-Nd-Pb-He Isotopes", "uid": "p0000081", "west": -112.5}, {"awards": "0944266 Twickler, Mark; 0944348 Taylor, Kendrick", "bounds_geometry": "POINT(-112.1115 -79.481)", "dataset_titles": "Summary of Results from the WAIS Divide Ice Core Project; WAIS Divide WDC06A Core Quality Versus Depth", "datasets": [{"dataset_uid": "601021", "doi": "10.15784/601021", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide Ice Core", "people": "Taylor, Kendrick C.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Summary of Results from the WAIS Divide Ice Core Project", "url": "https://www.usap-dc.org/view/dataset/601021"}, {"dataset_uid": "601030", "doi": "10.15784/601030", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS Divide Ice Core", "people": "Souney, Joseph Jr.; Twickler, Mark; Taylor, Kendrick C.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide WDC06A Core Quality Versus Depth", "url": "https://www.usap-dc.org/view/dataset/601030"}], "date_created": "Fri, 09 Jun 2017 00:00:00 GMT", "description": "Taylor/0944348\u003cbr/\u003e\u003cbr/\u003eThis award supports renewal of funding of the WAIS Divide Science Coordination Office (SCO). The Science Coordination Office (SCO) was established to represent the research community and facilitates the project by working with support organizations responsible for logistics, drilling, and core curation. During the last five years, 26 projects have been individually funded to work on this effort and 1,511 m of the total 3,470 m of ice at the site has been collected. This proposal seeks funding to continue the SCO and related field operations needed to complete the WAIS Divide ice core project. Tasks for the SCO during the second five years include planning and oversight of logistics, drilling, and core curation; coordinating research activities in the field; assisting in curation of the core in the field; allocating samples to individual projects; coordinating the sampling effort; collecting, archiving, and distributing data and other information about the project; hosting an annual science meeting; and facilitating collaborative efforts among the research groups. The intellectual merit of the WAIS Divide project is to better predict how human-caused increases in greenhouse gases will alter climate requires an improved understanding of how previous natural changes in greenhouse gases influenced climate in the past. Information on previous climate changes is used to validate the physics and results of climate models that are used to predict future climate. Antarctic ice cores are the only source of samples of the paleo-atmosphere that can be used to determine previous concentrations of carbon dioxide. Ice cores also contain records of other components of the climate system such as the paleo air and ocean temperature, atmospheric loading of aerosols, and indicators of atmospheric transport. The WAIS Divide ice core project has been designed to obtain the best possible record of greenhouse gases during the last glacial cycle (last ~100,000 years). The site was selected because it has the best balance of high annual snowfall (23 cm of ice equivalent/year), low dust Antarctic ice that does not compromise the carbon dioxide record, and favorable glaciology. The main science objectives of the project are to investigate climate forcing by greenhouse gases, initiation of climate changes, stability of the West Antarctic Ice Sheet, and cryobiology in the ice core. The project has numerous broader impacts. An established provider of educational material (Teachers? Domain) will develop and distribute web-based resources related to the project and climate change for use in K?12 classrooms. These resources will consist of video and interactive graphics that explain how and why ice cores are collected, and what they tell us about future climate change. Members of the national media will be included in the field team and the SCO will assist in presenting information to the general public. Video of the project will be collected and made available for general use. Finally, an opportunity will be created for cryosphere students and early career scientists to participate in field activities and core analysis. An ice core archive will be available for future projects and scientific discoveries from the project can be used by policy makers to make informed decisions.", "east": -112.1115, "geometry": "POINT(-112.1115 -79.481)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -79.481, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Mark, Twickler; Taylor, Kendrick C.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.481, "title": "Collaborative Research: Climate, Ice Dynamics and Biology using a Deep Ice Core from the West Antarctic Ice Sheet Ice Divide", "uid": "p0000080", "west": -112.1115}, {"awards": "0838936 Brook, Edward; 0839031 Severinghaus, Jeffrey", "bounds_geometry": "POINT(161.75 -77.75)", "dataset_titles": "Measurements of 14C-methane for the Younger Dryas - Preboreal Transition from Taylor Glacier, Antarctica; Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica; Taylor Glacier chemistry data and Taylor Dome TD2015 time scale; Taylor Glacier CO2 record; Taylor Glacier Gas Isotope Data", "datasets": [{"dataset_uid": "600165", "doi": "10.15784/600165", "keywords": "Antarctica; Cosmogenic; Cryosphere; Geochemistry; Ice Core Records; Paleoclimate; Radiocarbon; Taylor Glacier; Transantarctic Mountains", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Measurements of in situ cosmogenic 14C from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600165"}, {"dataset_uid": "601033", "doi": "10.15784/601033", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciology; Ice Core Records; Isotope; Solid Earth; Taylor Glacier; Transantarctic Mountains", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier Gas Isotope Data", "url": "https://www.usap-dc.org/view/dataset/601033"}, {"dataset_uid": "601029", "doi": "10.15784/601029", "keywords": "Antarctica; Chemistry:Rock; Critical Zone; Cryosphere; Geochemistry; Methane; Paleoclimate; Sample/Collection Description; Solid Earth; Taylor Glacier; Transantarctic Mountains; Younger Dryas", "people": "Severinghaus, Jeffrey P.; Petrenko, Vasilii", "repository": "USAP-DC", "science_program": null, "title": "Measurements of 14C-methane for the Younger Dryas - Preboreal Transition from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601029"}, {"dataset_uid": "000158", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Taylor Glacier CO2 record", "url": "ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/taylor/taylor2016d13co2.txt"}, {"dataset_uid": "601103", "doi": "10.15784/601103", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Horizontal Ice Core; Ice Core Records; Taylor Dome; Taylor Dome Ice Core", "people": "Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier chemistry data and Taylor Dome TD2015 time scale", "url": "https://www.usap-dc.org/view/dataset/601103"}], "date_created": "Tue, 29 Mar 2016 00:00:00 GMT", "description": "Severinghaus/0839031 \u003cbr/\u003e\u003cbr/\u003eThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a precise gas-based chronology for an archive of large-volume samples of the ancient atmosphere, which would enable ultra-trace gas measurements that are currently precluded by sample size limitations of ice cores. The intellectual merit of the proposed work is that it will provide a critical test of the \"clathrate hypothesis\" that methane clathrates contributed to the two abrupt atmospheric methane concentration increases during the last deglaciation 15 and 11 kyr ago. This approach employs large volumes of ice (\u003e1 ton) to measure carbon-14 on past atmospheric methane across the abrupt events. Carbon-14 is an ideal discriminator of fossil sources of methane to the atmosphere, because most methane sources (e.g., wetlands, termites, biomass burning) are rich in carbon-14, whereas clathrates and other fossil sources are devoid of carbon-14. The proposed work is a logical extension to Taylor Glacier, Antarctica, of an approach pioneered at the margin of the Greenland ice sheet over the past 7 years. The Greenland work found higher-than-expected carbon-14 values, likely due in part to contaminants stemming from the high impurity content of Greenland ice and the interaction of the ice with sediments from the glacier bed. The data also pointed to the possibility of a previously unknown process, in-situ cosmogenic production of carbon-14 methane (radiomethane) in the ice matrix. Antarctic ice in Taylor Glacier is orders of magnitude cleaner than the ice at the Greenland site, and is much colder and less stratigraphically disturbed, offering the potential for a clear resolution of this puzzle and a definitive test of the cosmogenic radiomethane hypothesis. Even if cosmogenic radiomethane in ice is found, it still may be possible to reconstruct atmospheric radiomethane with a correction enabled by a detailed understanding of the process, which will be sought by co-measuring carbon-14 in carbon monoxide and carbon dioxide. The broader impacts of the proposed work are that the clathrate test may shed light on the stability of the clathrate reservoir and its potential for climate feedbacks under human-induced warming. Development of Taylor Glacier as a \"horizontal ice core\" would provide a community resource for other researchers. Education of one postdoc, one graduate student, and one undergraduate, would add to human resources. This award has field work in Antarctica.", "east": 161.75, "geometry": "POINT(161.75 -77.75)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; Not provided; USAP-DC", "locations": null, "north": -77.75, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e PLEISTOCENE", "persons": "Brook, Edward J.; Severinghaus, Jeffrey P.", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "NCEI; USAP-DC", "science_programs": null, "south": -77.75, "title": "Collaborative Research: A \"Horizontal Ice Core\" for Large-Volume Samples of the Past Atmosphere, Taylor Glacier, Antarctica", "uid": "p0000099", "west": 161.75}, {"awards": "1043780 Aydin, Murat", "bounds_geometry": null, "dataset_titles": "Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core; Ultra-trace Measurements in the WAIS Divide 06A Ice Core", "datasets": [{"dataset_uid": "601361", "doi": "10.15784/601361", "keywords": "Antarctica; Carbonyl Sulfide; Cryosphere; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - Taylor Dome M3C1 Ice Core", "url": "https://www.usap-dc.org/view/dataset/601361"}, {"dataset_uid": "609659", "doi": "10.7265/N5CV4FPK", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; WAIS divide; WAIS Divide Ice Core", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Ultra-trace Measurements in the WAIS Divide 06A Ice Core", "url": "https://www.usap-dc.org/view/dataset/609659"}], "date_created": "Tue, 27 Oct 2015 00:00:00 GMT", "description": "Aydin/1043780\u003cbr/\u003eThis award supports the analysis of the trace gas carbonyl sulfide (COS) in a deep ice core from West Antarctic Ice Sheet Divide (WAIS-D), Antarctica. COS is the most abundant sulfur gas in the troposphere and a precursor of stratospheric sulfate. It has a large terrestrial COS sink that is tightly coupled to the photosynthetic uptake of atmospheric carbon dioxide (CO2). The primary goal of this project is to develop high a resolution Holocene record of COS from the WAIS-D 06A ice core. The main objectives are 1) to assess the natural variability of COS and the extent to which its atmospheric variability was influenced by climate variability, and 2) to examine the relationship between changes in atmospheric COS and CO2. This project also includes low-resolution sampling and analysis of COS from 10,000-30,000 yrs BP, covering the transition from the Last Glacial Maximum into the early Holocene. The goal of this work is to assess the stability of COS in ice core air over long time scales and to establish the COS levels during the last glacial maximum and the magnitude of the change between glacial and interglacial conditions. The results of this work will be disseminated via peer-review publications and will contribute to environmental assessments such as the WMO Stratospheric Ozone Assessment and IPCC Climate Assessment. This project will support a PhD student and undergraduate researcher in the Department of Earth System Science at the University of California, Irvine, and will create summer research opportunities for undergraduates from non-research active Universities.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Ethane; LABORATORY; n-butane; Carbonyl Sulfide; Propane; Methyl Bromide; Methyl Chloride; Carbon Disulfide", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Earth Sciences", "paleo_time": null, "persons": "Aydin, Murat; Saltzman, Eric", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": null, "title": "Carbonyl Sulfide Measurements in the Deep West Antarctic Ice Sheet Divide Ice Core", "uid": "p0000055", "west": null}, {"awards": "1246148 Severinghaus, Jeffrey; 1245659 Petrenko, Vasilii; 1245821 Brook, Edward", "bounds_geometry": "POINT(162.167 -77.733)", "dataset_titles": "Gas and Dust Measurements for Taylor Glacier and Taylor Dome Ice Cores; Last Interglacial Mean Ocean Temperature; Mean Ocean Temperature in Marine Isotope Stage 4; Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation; N2O Concentration and Isotope Data for 74-59 ka from Taylor Glacier, Antarctica; Taylor Glacier CO2 Isotope Data 74-59 kyr; Taylor Glacier Noble Gases - Younger Dryas; The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "datasets": [{"dataset_uid": "600163", "doi": "10.15784/600163", "keywords": "Antarctica; Atmosphere; Cryosphere; Geochemistry; Ice Core Records; Isotope; Paleoclimate; Taylor Glacier; Transantarctic Mountains", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": null, "title": "The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "url": "https://www.usap-dc.org/view/dataset/600163"}, {"dataset_uid": "601260", "doi": "10.15784/601260", "keywords": "Antarctica; Carbon-14; Cosmogenic; Cryosphere; Ice Core; Methane", "people": "Petrenko, Vasilii; Dyonisius, Michael", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Measurements of 14CH4 and 14CO in ice from Taylor Glacier: Last Deglaciation", "url": "https://www.usap-dc.org/view/dataset/601260"}, {"dataset_uid": "601600", "doi": "10.15784/601600", "keywords": "Antarctica; Cryosphere; Taylor Glacier", "people": "Dyonisius, Michael; Bauska, Thomas; Petrenko, Vasilii; Shackleton, Sarah; Menking, Andy; Buffen, Aron; Severinghaus, Jeffrey P.; Barker, Stephen; Brook, Edward J.; Menking, James", "repository": "USAP-DC", "science_program": null, "title": "Taylor Glacier CO2 Isotope Data 74-59 kyr", "url": "https://www.usap-dc.org/view/dataset/601600"}, {"dataset_uid": "601176", "doi": "10.15784/601176", "keywords": "Antarctica; CO2; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Methane; Noble Gas; Noble Gas Isotopes; Snow/Ice; Taylor Glacier; Younger Dryas", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Glacier Noble Gases - Younger Dryas", "url": "https://www.usap-dc.org/view/dataset/601176"}, {"dataset_uid": "601198", "doi": "10.15784/601198", "keywords": "Antarctica; Blue Ice Area; Chemistry:Ice; CO2; Cryosphere; Dust; Gas; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; Mass Spectrometer; Methane; Nitrogen Isotopes; Oxygen Isotopes; Paleoclimate; Snow/Ice; Taylor Dome; Taylor Dome Ice Core", "people": "Petrenko, Vasilii; Baggenstos, Daniel; Bauska, Thomas; Rhodes, Rachel; McConnell, Joseph; Severinghaus, Jeffrey P.; Dyonisius, Michael; Shackleton, Sarah; Barker, Stephen; Marcott, Shaun; Brook, Edward J.; Menking, James", "repository": "USAP-DC", "science_program": null, "title": "Gas and Dust Measurements for Taylor Glacier and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/601198"}, {"dataset_uid": "601218", "doi": "10.15784/601218", "keywords": "Antarctica; Carbon-14; Carbon Dioxide; Chemistry:Ice; CO2; Cryosphere; Dome C Ice Core; EPICA; EPICA Dome C; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; isotope data; Last Interglacial; Mass Spectrometer; Mass Spectrometry; Methane; Oxygen; Oxygen Isotopes; Paleotemperature; Pleistocene; Snow/Ice; Taylor Dome Ice Core; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Dome C Ice Core", "title": "Last Interglacial Mean Ocean Temperature", "url": "https://www.usap-dc.org/view/dataset/601218"}, {"dataset_uid": "601415", "doi": "10.15784/601415", "keywords": "Antarctica; Cryosphere; Glaciology; Ice Core Data; Ice Core Records; Paleoclimate; Paleotemperature; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": null, "title": "Mean Ocean Temperature in Marine Isotope Stage 4", "url": "https://www.usap-dc.org/view/dataset/601415"}, {"dataset_uid": "601218", "doi": "10.15784/601218", "keywords": "Antarctica; Carbon-14; Carbon Dioxide; Chemistry:Ice; CO2; Cryosphere; Dome C Ice Core; EPICA; EPICA Dome C; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice; Ice Core Chemistry; Ice Core Data; Ice Core Gas Records; Ice Core Records; isotope data; Last Interglacial; Mass Spectrometer; Mass Spectrometry; Methane; Oxygen; Oxygen Isotopes; Paleotemperature; Pleistocene; Snow/Ice; Taylor Dome Ice Core; Taylor Glacier", "people": "Shackleton, Sarah", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Last Interglacial Mean Ocean Temperature", "url": "https://www.usap-dc.org/view/dataset/601218"}, {"dataset_uid": "601398", "doi": "10.15784/601398", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Data; Ice Core Gas Records; Ice Core Records; Marine Isotope Stage 4; MIS 4; Nitrous Oxide; Pleistocene; Taylor Dome Ice Core; Taylor Glacier", "people": "Petrenko, Vasilii; Shackleton, Sarah; Brook, Edward J.; Schilt, Adrian; Dyonisius, Michael; Severinghaus, Jeffrey P.; Menking, James", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "N2O Concentration and Isotope Data for 74-59 ka from Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/601398"}], "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, \u0026#948;18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, \u0026#948;13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of \u0026#948;13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.", "east": 162.167, "geometry": "POINT(162.167 -77.733)", "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 SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Not provided; USAP-DC; FIELD INVESTIGATION; Stratigraphy; FIELD SURVEYS; Antarctica; Methane; Ice Core; paleoenvironmental; Carbon Dioxide; FIXED OBSERVATION STATIONS; Stable Isotopes; Ablation Zone; Taylor Glacier; Nitrous Oxide; USA/NSF; LABORATORY; AMD; Cosmogenic; AMD/US", "locations": "Taylor Glacier; Antarctica", "north": -77.733, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Petrenko, Vasilii; Brook, Edward J.; Severinghaus, Jeffrey P.; PETRENKO, VASILLI", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e FIXED OBSERVATION STATIONS; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": -77.733, "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "uid": "p0000283", "west": 162.167}, {"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: \u003cbr/\u003eRecent 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.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe 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; K ICE: Testing the Cretaceous Glaciation Hypothesis", "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": "0944343 Severinghaus, Jeffrey", "bounds_geometry": "POINT(-112.05 -79.28)", "dataset_titles": null, "datasets": null, "date_created": "Fri, 15 Aug 2014 00:00:00 GMT", "description": "Severinghaus/0944343\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop both a record of past local temperature change at the WAIS Divide site, and past mean ocean temperature using solubility effects on atmospheric krypton and xenon. The two sets of products share some of the same measurements, because the local temperature is necessary to make corrections to krypton and xenon, and thus synergistically support each other. Further scientific synergy is obtained by the fact that the mean ocean temperature is constrained to vary rather slowly, on a 1000-yr timescale, due to the mixing time of the deep ocean. Thus rapid changes are not expected, and can be used to flag methodological problems if they appear in the krypton and xenon records. The mean ocean temperature record produced will have a temporal resolution of 500 years, and will cover the entire 3400 m length of the core. This record will be used to test hypotheses regarding the cause of atmospheric carbon dioxide (CO2) variations, including the notion that deep ocean stratification via a cold salty stagnant layer caused atmospheric CO2 drawdown during the last glacial period. The local surface temperature record that results will synergistically combine with independent borehole thermometry and water isotope records to produce a uniquely precise and accurate temperature history for Antarctica, on a par with the Greenland temperature histories. This history will be used to test hypotheses that the ?bipolar seesaw? is forced from the North Atlantic Ocean, which makes a specific prediction that the timing of Antarctic cooling should slightly lag abrupt Greenland warming. The WAIS Divide ice core is expected to be the premier atmospheric gas record of the past 100,000 years for the foreseeable future, and as such, making this set of high precision noble gas measurements adds value to the other gas records because they all share a common timescale and affect each other in terms of physical processes such as gravitational fractionation. Broader impact of the proposed work: The clarification of timing of atmospheric CO2 and Antarctic surface temperature, along with deep ocean temperature, will aid in efforts to understand the feedbacks among CO2, temperature, and ocean circulation. These feedbacks bear on the future response of the Earth System to anthropogenic forcing. A deeper understanding of the mechanism of deglaciation, and the role of atmospheric CO2, will go a long way towards clarifying a topic that has become quite confused in the public mind in the public debate over climate change. Elucidating the role of the bipolar seesaw in ending glaciations and triggering CO2 increases may also provide an important warning that this represents a potential positive feedback, not currently considered by IPCC. Education of one graduate student, and training of one technician, will add to the nation?s human resource base. Outreach activities will be enhanced and will to continue to entrain young people in discovery, and excitement will enhance the training of the next generation of scientists and educators.", "east": -112.05, "geometry": "POINT(-112.05 -79.28)", "instruments": null, "is_usap_dc": false, "keywords": "Nobel gases; FIELD INVESTIGATION; Climate; Xenon; FIELD SURVEYS; Ice Core; Antarctica; Krypton; LABORATORY", "locations": "Antarctica", "north": -79.28, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repositories": null, "science_programs": null, "south": -79.28, "title": "Noble Gases in the WAIS Divide Ice Core as Indicators of Local and Mean-ocean Temperature", "uid": "p0000430", "west": -112.05}, {"awards": "1232962 Ledwell, James", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP1310A", "datasets": [{"dataset_uid": "002658", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1310A", "url": "https://www.rvdata.us/search/cruise/NBP1310A"}], "date_created": "Fri, 07 Feb 2014 00:00:00 GMT", "description": "Intellectual Merit: The Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) is a study of ocean mixing in the Antarctic Circumpolar Current (ACC) which runs west to east all around the continent of Antarctica, south of the other continents. This current system is somewhat of a barrier to transport of heat, carbon dioxide and other important ocean constituents between the far south and the rest of the ocean, and mixing processes play an important role in those transports. DIMES is a multi-investigator cooperative project, led by physical oceanographers in the U.S. and in the U.K. A passive tracer and an array of sub-surface floats were deployed early in 2009 more than 2000 km west of Drake Passage on a surface of constant density about 1500 m deep between the Sub Antarctic Front and the Polar Front of the ACC. In early 2010 a U.S. led research cruise sampled the tracer, turbulence levels, and the velocity and density profiles that govern the generation of that turbulence, and additional U.K. led research cruises in 2011 and 2012 continue this sampling as the tracer has made its way through Drake Passage, into the Scotia Sea, and over the North Scotia Ridge, a track of more than 3000 km. The initial results show that diapycnal, i.e., vertical, mixing west of Drake Passage where the bottom is relatively smooth is no larger than in most other regions of the open ocean. In contrast, there are strong velocity shears and intense turbulence levels over the rough topography in Drake Passage and diapycnal diffusivity of the tracer more than 10 times larger in Drake Passage and to the east than west of Drake Passage.\u003cbr/\u003e\u003cbr/\u003eThe DIMES field program continues with the U.S. team collecting new velocity and turbulence data in the Scotia Sea. It is anticipated that the tracer will continue passing through the Scotia Sea until at least early 2014. The U.K. partners have scheduled sampling of the tracer on cruises at the North Scotia Ridge and in the eastern and central Scotia Sea in early 2013 and early 2014. The current project will continue the time series of the tracer at Drake Passage on two more U.S. led cruises, in late 2012 and late 2013. Trajectories through the Scotia Sea estimated from the tracer observations, from neutrally buoyant floats, and from numerical models will be used to accurately estimate mixing rates of the tracer and to locate where the mixing is concentrated. During the 2013 cruise the velocity and turbulence fields along high-resolution transects along the ACC and across the ridges of Drake Passage will be measured to see how far downstream of the ridges the mixing is enhanced, and to test the hypothesis that mixing is enhanced by breaking lee waves generated by flow over the rough topography.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts: DIMES (see web site at http://dimes.ucsd.edu) involves many graduate students and post-doctoral researchers. Two graduate students, who would become expert in ocean turbulence and the processes generating it, will continue be trained on this project. The work in DIMES is ultimately motivated by the need to understand the overturning circulation of the global ocean. This circulation governs the transport and storage of heat and carbon dioxide within the huge oceanic reservoir, and thus plays a major role in regulating the earth?s climate. Understanding the circulation and how it changes in reaction to external forces is necessary to the understanding of past climate change and of how climate might change in the future, and is therefore of great importance to human well-being. The data collected and analyzed by the DIMES project will be assembled and made publicly available at the end of the project.\u003cbr/\u003e\u003cbr/\u003eThe DIMES project is a process experiment sponsored by the U.S. CLIVAR (Climate variability and predictability) program.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": "Ledwell, James", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Studies of Turbulence and Mixing in the Antarctic Circumpolar Current, a Continuation of DIMES", "uid": "p0000846", "west": null}, {"awards": "0944764 Brook, Edward", "bounds_geometry": null, "dataset_titles": "Abrupt Change in Atmospheric CO2 During the Last Ice Age; High-resolution Atmospheric CO2 during 7.4-9.0 ka", "datasets": [{"dataset_uid": "609539", "doi": "10.7265/N5F47M23", "keywords": "Antarctica; Arctic; Byrd; Chemistry:Fluid; CO2; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; Siple Dome Ice Core; Taylor Dome; Taylor Dome Ice Core", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Abrupt Change in Atmospheric CO2 During the Last Ice Age", "url": "https://www.usap-dc.org/view/dataset/609539"}, {"dataset_uid": "609527", "doi": "10.7265/N5QF8QT5", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Geochronology; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; South Pole; WAISCORES", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "High-resolution Atmospheric CO2 during 7.4-9.0 ka", "url": "https://www.usap-dc.org/view/dataset/609527"}, {"dataset_uid": "609539", "doi": "10.7265/N5F47M23", "keywords": "Antarctica; Arctic; Byrd; Chemistry:Fluid; CO2; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; Siple Dome Ice Core; Taylor Dome; Taylor Dome Ice Core", "people": "Ahn, Jinho; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Abrupt Change in Atmospheric CO2 During the Last Ice Age", "url": "https://www.usap-dc.org/view/dataset/609539"}, {"dataset_uid": "609539", "doi": "10.7265/N5F47M23", "keywords": "Antarctica; Arctic; Byrd; Chemistry:Fluid; CO2; Cryosphere; Geochemistry; GISP2; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Paleoclimate; Siple Dome Ice Core; Taylor Dome; Taylor Dome Ice Core", "people": "Brook, Edward J.; Ahn, Jinho", "repository": "USAP-DC", "science_program": "Byrd Ice Core", "title": "Abrupt Change in Atmospheric CO2 During the Last Ice Age", "url": "https://www.usap-dc.org/view/dataset/609539"}], "date_created": "Thu, 08 Aug 2013 00:00:00 GMT", "description": "This award supports a project to create new, unprecedented high-resolution atmospheric carbon dioxide (CO2) records spanning intervals of abrupt climate changes during the last glacial period and the early Holocene. The proposed work will utilize high-precision methods on existing ice cores from high accumulation sites such as Siple Dome and Byrd Station, Antarctica and will improve our understanding of how fast CO2 can change naturally, how its variations are linked with climate, and, combined with a coupled climate-carbon cycle model, will clarify the role of terrestrial and oceanic processes during past abrupt changes of climate and CO2. The intellectual merit of this work is that CO2 is the most important anthropogenic greenhouse gas and understanding its past variations, its sources and sinks, and how they are linked to climate change is a major goal of the climate research community. This project will produce high quality data on centennial to multi-decadal time scales. Such high-resolution work has not been conducted before because of insufficient analytical precision, slow experimental procedures in previous studies, or lack of available samples. The proposed research will complement future high-resolution studies from WAIS Divide ice cores and will provide ice core CO2 records for the target age intervals, which are in the zone of clathrate formation in the WAIS ice cores. Clathrate hydrate is a phase composed of air and ice. CO2 analyses have historically been less precise in clathrate ice than in ?bubbly ice? such as the Siple Dome ice core that will be analyzed in the proposed project. High quality, high-resolution results from specific intervals in Siple Dome that we propose to analyze will provide important data for verifying the WAIS Divide record. The broader impacts of the work are that current models show a large uncertainty of future climate-carbon cycle interactions. The results of this proposed work will be used for testing coupled carbon cycle-climate models and may contribute to reducing this uncertainty. The project will contribute to the training of several undergraduate students and a full-time technician. Both will learn analytical techniques and the basic science involved. Minorities and female students will be highly encouraged to participate in this project. Outreach efforts will include participation in news media interviews, at a local festival celebrating art, science and technology, and giving seminar presentations in the US and foreign countries. The OSU ice core laboratory has begun a collaboration with a regional science museum and is developing ideas to build an exhibition booth to make public be aware of climate change and ice core research. All data will be archived at the National Snow and Ice Data Center and at other similar archives per the OPP data policy.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e CO2 ANALYZERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "GROUND-BASED OBSERVATIONS; AGDC-project; CH4 concentrations; Ice Core Gas Age; CO2 concentrations; CO2 Uncertainty; LABORATORY; Ice Core Depth; Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "NOT APPLICABLE; NOT APPLICABLE", "persons": "Ahn, Jinho; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Atmospheric CO2 and Abrupt Climate Change", "uid": "p0000179", "west": null}, {"awards": "0739766 Brook, Edward", "bounds_geometry": "POINT(-112.08 -79.47)", "dataset_titles": "WAIS Divide Ice Core CO2", "datasets": [{"dataset_uid": "609651", "doi": "10.7265/N5DV1GTZ", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Marcott, Shaun; Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Ice Core CO2", "url": "https://www.usap-dc.org/view/dataset/609651"}], "date_created": "Wed, 30 May 2012 00:00:00 GMT", "description": "Brook 0739766\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to create a 25,000-year high-resolution record of atmospheric CO2 from the WAIS Divide ice core. The site has high ice accumulation rate, relatively cold temperatures, and annual layering that should be preserved back to 40,000 years, all prerequisite for preserving a high quality, well-dated CO2 record. The new record will be used to examine relationships between Antarctic climate, Northern Hemisphere climate, and atmospheric CO2 on glacial-interglacial to centennial time scales, at unprecedented temporal resolution. The intellectual merit of the proposed work is simply that CO2 is the most important greenhouse gas that humans directly impact, and understanding the sources, sinks, and controls of atmospheric CO2 is a major goal for the global scientific community. Accurate chronology and detailed records are primary requirements for developing and testing models that explain and predict CO2 variability. The proposed work has several broader impacts. It contributes to the training of a post-doctoral researcher, who will transfer to a research faculty position during the award period and who will participate in graduate teaching and guest lecture in undergraduate courses. An undergraduate researcher will gain valuable lab training and conduct independent research. Bringing the results of\u003cbr/\u003ethe proposed work to the classroom will enrich courses taught by the PI. Outreach efforts will expose pre-college students to ice core research. The proposed work will enhance the laboratory facilities for ice core research at OSU, insuring that the capability for CO2 measurements exists for future projects. All data will be archived at the National Snow and Ice Data Center and other similar archives, per OPP policy. Highly significant results will be disseminated to the news media through OSU?s very effective News and Communications group. Carbon dioxide is the most important greenhouse gas that humans are directly changing. Understanding how CO2 and climate are linked on all time scales is necessary for predicting the future behavior of the carbon cycle and climate system, primarily to insure that the appropriate processes are represented in carbon cycle/climate models. Part of the proposed work emphasizes the relationship of CO2 and abrupt climate change. Understanding how future abrupt change might impact the carbon cycle is an important issue for society.", "east": -112.08, "geometry": "POINT(-112.08 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": true, "keywords": "Carbon Dioxide; FIELD INVESTIGATION; Antarctic ice core; AGDC-project; CO2; Ice Core; Antarctica; Climate; Gas Chromatography; WAIS Divide-project; LABORATORY", "locations": "Antarctica", "north": -79.47, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Marcott, Shaun; Ahn, Jinho; Brook, Edward J.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.47, "title": "Atmospheric Carbon Dioxide and Climate Change: The WAIS Divide Ice Core Record", "uid": "p0000044", "west": -112.08}, {"awards": "0836112 Smith, Walker; 0836144 Yager, Patricia; 0836061 Dennett, Mark", "bounds_geometry": "POLYGON((100 -69,107 -69,114 -69,121 -69,128 -69,135 -69,142 -69,149 -69,156 -69,163 -69,170 -69,170 -70,170 -71,170 -72,170 -73,170 -74,170 -75,170 -76,170 -77,170 -78,170 -79,163 -79,156 -79,149 -79,142 -79,135 -79,128 -79,121 -79,114 -79,107 -79,100 -79,100 -78,100 -77,100 -76,100 -75,100 -74,100 -73,100 -72,100 -71,100 -70,100 -69))", "dataset_titles": "Amundsen Sea Polynya International Research Expedition (ASPIRE) data; Controls on Climate-Active Gases by Amundsen Sea Ice Biota", "datasets": [{"dataset_uid": "600092", "doi": "10.15784/600092", "keywords": "Amundsen Sea; Antarctica; Chemistry:Fluid; Cryosphere; CTD Data; Oceans; Oden; Oden2008; Sea Ice; Sea Surface; Southern Ocean", "people": "Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Controls on Climate-Active Gases by Amundsen Sea Ice Biota", "url": "https://www.usap-dc.org/view/dataset/600092"}, {"dataset_uid": "600091", "doi": "10.15784/600091", "keywords": "Amundsen Sea; Antarctica; Biology; Biosphere; Cryosphere; Oceans; Oden; Oden2008; Plankton; Sea Ice; Southern Ocean", "people": "Dennett, Mark", "repository": "USAP-DC", "science_program": null, "title": "Controls on Climate-Active Gases by Amundsen Sea Ice Biota", "url": "https://www.usap-dc.org/view/dataset/600091"}, {"dataset_uid": "000146", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Amundsen Sea Polynya International Research Expedition (ASPIRE) data", "url": "https://www.bco-dmo.org/project/2132"}], "date_created": "Sun, 24 Apr 2011 00:00:00 GMT", "description": "Convincing evidence now confirms that polar regions are changing rapidly in response to human activities. Changes in sea ice extent and thickness will have profound implications for productivity, food webs and carbon fluxes at high latitudes, since sea ice biota are a significant source of biogenic matter for the ecosystem. While sea ice is often thought to be a barrier to gas exchange between the ocean and the atmosphere, it more likely functions as a source or sink for climate-active gases such as carbon dioxide and ozone-depleting organohalogens, due in part to activities of microbes embedded in the sea ice matrix. This project brings together experienced US and Swedish investigators to examine the controls by sea-ice biota on the production and degradation of key climate-active gases in the Pacific sector of the Southern Ocean. We hypothesize that 1) the physical properties of the sea-ice environment will determine the community structure and activities of the sea ice biota; 2) the productivity, biomass, physiological state and species composition of ice algae will determine the production of specific classes of organic carbon, including organohalogens; 3) heterotrophic co-metabolism within the ice will break down these compounds to some extent, depending on the microbial community structure and productivity, and 4) the sea ice to atmosphere fluxes of CO2 and organohalogens will be inversely related. This project will build close scientific collaborations between US and Swedish researchers and also train young scientists, including members of underrepresented groups. Dissemination of results will include the scientific literature, and public outreach venues including interactions with a PolarTrec teacher.", "east": 170.0, "geometry": "POINT(135 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -69.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker; Yager, Patricia; Dennett, Mark", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "BCO-DMO; USAP-DC", "science_programs": null, "south": -79.0, "title": "Collaborative Research: Controls on climate-active gases by Amundsen Sea ice biota", "uid": "p0000137", "west": 100.0}, {"awards": "0538479 Seibel, Brad", "bounds_geometry": "POLYGON((166 -77,166.1 -77,166.2 -77,166.3 -77,166.4 -77,166.5 -77,166.6 -77,166.7 -77,166.8 -77,166.9 -77,167 -77,167 -77.1,167 -77.2,167 -77.3,167 -77.4,167 -77.5,167 -77.6,167 -77.7,167 -77.8,167 -77.9,167 -78,166.9 -78,166.8 -78,166.7 -78,166.6 -78,166.5 -78,166.4 -78,166.3 -78,166.2 -78,166.1 -78,166 -78,166 -77.9,166 -77.8,166 -77.7,166 -77.6,166 -77.5,166 -77.4,166 -77.3,166 -77.2,166 -77.1,166 -77))", "dataset_titles": "Impacts of Elevated pCO2 on a Dominant Aragonitic Pteropod (Thecosomata) and its Specialist Predator (Gymnosomata) in the Ross Sea", "datasets": [{"dataset_uid": "600055", "doi": "10.15784/600055", "keywords": "Biology; Biosphere; CO2; McMurdo Station; Oceans; Ross Island; Sample/Collection Description; Shell fish; Southern Ocean", "people": "Seibel, Brad", "repository": "USAP-DC", "science_program": null, "title": "Impacts of Elevated pCO2 on a Dominant Aragonitic Pteropod (Thecosomata) and its Specialist Predator (Gymnosomata) in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600055"}], "date_created": "Sat, 18 Dec 2010 00:00:00 GMT", "description": "Rising atmospheric carbon dioxide concentrations have resulted in greater oceanic uptake of anthropogenic carbon dioxide. Elevated partial pressure of carbon dioxide can impact marine organisms both via decreased carbonate saturation that affects calcification rates and via disturbance to acid-base (metabolic) physiology. Pteropod molluscs (Thecosomata) form shells made of aragonite, a type of calcium carbonate that is highly soluble, suggesting that these organisms may be particularly sensitive to increasing carbon dioxide and reduced carbonate ion concentration. Thecosome pteropods, which dominate the calcium carbonate export south of the Antarctic Polar Front, will be the first major group of marine calcifying organisms to experience carbonate undersaturation within parts of their present-day geographical ranges as a result of anthropogenic carbon dioxide. An unusual, co-evolved relationship between thecosomes and their specialized gymnosome predators provides a unique backdrop against which to assess the physiological and ecological importance of elevated partial pressure of carbon dioxide. Pteropods are functionally important components of the Antarctic ecosystem with potential to influence phytoplankton stocks, carbon export, and dimethyl sulfide levels that, in turn, influence global climate through ocean-atmosphere feedback loops. The research will quantify the impact of elevated carbon dioxide on a dominant aragonitic pteropod, Limacina helicina, and its specialist predator, the gymnosome Clione antarctica, in the Ross Sea through laboratory experimentation. Results will be disseminated broadly to enhance scientific understanding in this field. The project involves collaboration between researchers at a predominantly undergraduate institution with a significant enrollment of students that are typically underrepresented in the research environment (California State University San Marcos - CSUSM) and at a Ph.D.-granting institution (University of Rhode Island - URI). The program will promote education and learning through the joint education of undergraduate students and graduate students at CSUSM and URI as part of a research team, as well as through the teaching activities of the principal investigators. Dr. Keating, CSUSM professor of science education, will participate in the McMurdo fieldwork and lead the outreach opportunities for the project.", "east": 167.0, "geometry": "POINT(166.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Seibel, Brad", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Impacts of Elevated pCO2 on a Dominant Aragonitic Pteropod (Thecosomata) and its Specialist Predator (Gymnosomata) in the Ross Sea", "uid": "p0000694", "west": 166.0}, {"awards": "0338157 Smith, Walker; 0338350 Dunbar, Robert; 0338097 DiTullio, Giacomo; 0741411 Hutchins, David; 0127037 Neale, Patrick", "bounds_geometry": "POLYGON((173.31833 -46.5719,173.757539 -46.5719,174.196748 -46.5719,174.635957 -46.5719,175.075166 -46.5719,175.514375 -46.5719,175.953584 -46.5719,176.392793 -46.5719,176.832002 -46.5719,177.271211 -46.5719,177.71042 -46.5719,177.71042 -48.759516,177.71042 -50.947132,177.71042 -53.134748,177.71042 -55.322364,177.71042 -57.50998,177.71042 -59.697596,177.71042 -61.885212,177.71042 -64.072828,177.71042 -66.260444,177.71042 -68.44806,177.271211 -68.44806,176.832002 -68.44806,176.392793 -68.44806,175.953584 -68.44806,175.514375 -68.44806,175.075166 -68.44806,174.635957 -68.44806,174.196748 -68.44806,173.757539 -68.44806,173.31833 -68.44806,173.31833 -66.260444,173.31833 -64.072828,173.31833 -61.885212,173.31833 -59.697596,173.31833 -57.50998,173.31833 -55.322364,173.31833 -53.134748,173.31833 -50.947132,173.31833 -48.759516,173.31833 -46.5719))", "dataset_titles": "Expedition Data; Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea; Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. 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Palmer expedition NBP0601", "url": "https://www.usap-dc.org/view/dataset/601340"}, {"dataset_uid": "001687", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0305"}, {"dataset_uid": "600036", "doi": "10.15784/600036", "keywords": "Biology; Biosphere; Chemistry:Fluid; Diatom; Oceans; Phytoplankton; Ross Sea; Southern Ocean", "people": "DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600036"}, {"dataset_uid": "001584", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0508"}, {"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. 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It builds upon earlier successful studies of the inflow of intermediate water masses into the Eastern Weddell Sea, their modification within the Weddell Gyre, and their interaction with bottom water formation processes in the western Weddell Sea. The study is called Deep Ocean Ventilation Through Antarctic Intermediate Layers (DOVETAIL) and includes six components involving hydrographic measurements, natural tracer experiments, and modeling studies. The study will be centered east of the Drake Passage where water masses from the Weddell Sea and the Scotia Sea come together in the Weddell-Scotia Confluence, and will be carried out in cooperation with the national antarctic programs of Germany and Spain. This particular component concerns observations of the temperature and salinity structure, as well as the chemical nature of the water column in the confluence region. The study has four related objectives. The first is to assess the quantity and the physical and chemical characteristics of Weddell Sea source waters for the confluence. The second is to describe the dominant processes associated with spreading and sinking of dense antarctic waters within the Weddell-Scotia Confluence. The third is to estimate the ventilation rate of the world ocean, and the fourth is to estimate seasonal fluctuations in the regional ocean transport and hydrographic structure and to assess the likely influence of seasonal to interannual variability on rates of ventilation by Weddell Sea waters. Ventilation of the deep ocean -- the rising of sub-surface water masses to the surface to be recharged with atmospheric gases and to give up heat to the atmosphere -- is a uniquely antarctic phenomenon that has significant consequences for global change by affecting the g lobal reservoir of carbon dioxide, and by modulating the amount and extent of seasonal sea ice in the southern hemisphere. This component will make systematic observations of the temperature salinity structure of the water and undertake an extensive sampling program for other chemical studies. The purpose is to identify the individual water masses and to relate their temperature and salinity characteristics to the modification processes within the Weddell Sea. ***", "east": -39.4436, "geometry": "POINT(-54.514955 -58.31195)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.35405, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Gordon, Arnold", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.26985, "title": "Deep Ocean Ventilation Through Antarctic Intermediate Layers (DOVETAIL)", "uid": "p0000630", "west": -69.58631}, {"awards": "0338164 Sedwick, Peter", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0601", "datasets": [{"dataset_uid": "001580", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0601"}, {"dataset_uid": "002619", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0601", "url": "https://www.rvdata.us/search/cruise/NBP0601"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The objectives of this proposal are to investigate the controls on the large-scale distribution and production of the two major bloom-forming phytoplankton taxa in the Southern Ocean, diatoms and Phaeocystis Antarctica. These two groups, through their involvement in the biogeochemical cycles of carbon, sulfur and nutrient elements, may have played important roles in the climate variations of the late Quaternary, and they also may be key players in future environmental change. A current paradigm is that irradiance and iron availability drive phytoplankton dynamics in the Southern Ocean. Recent work, however, suggests that carbon dioxide (CO2) concentrations may also be important in structuring algal assemblages, due to species-specific differences in the physiology. This proposal examines the interactive effects of iron, light and CO2 on the physiology, ecology and relative dominance of Phaeocystis and diatoms in the Southern Ocean. The Ross Sea is an ideal system in which to investigate the environmental factors that regulate the distribution and production of these two algal groups, since it is characterized by seasonal blooms of both P. Antarctica and diatoms that are typically separated in both space and time. This study will take the form of an interdisciplinary investigation that includes a field survey and statistical analysis of algal assemblage composition, iron, mixed layer depth, and CO2 levels in the southern Ross Sea, coupled with shipboard experiments to examine the response of diatom and P. Antarctica assemblages to high and low levels of iron, light and CO2 during spring and summer. \u003cbr/\u003eThis project will provide information on some of the major factors controlling the production and distribution of the two major bloom forming phytoplankton in the Southern Ocean and the related biogeochemical cycling of carbon, sulfur and nutrient elements. The results may ultimately advance the ability to predict how the Southern Ocean will be affected by and possibly modulate future climate change. This project will also make significant educational contributions at several levels, including the planned research involvement of graduate and undergraduate students, postdoctoral associates, a student teacher, and community outreach and educational activities. A number of activities are planned to interface the project with K-12 education. Presentations will be made at local schools to discuss the research and events of the research cruise. During the cruise there will be daily interactive email contact with elementary classrooms. Established websites will be used to allow students to learn about the ongoing research, and to allow researchers to communicate with students through text and downloaded images.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e WATER BOTTLES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Interactive Effects of Iron, Light and CO2 on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000831", "west": null}, {"awards": "9317379 Foster, Theodore", "bounds_geometry": "POLYGON((143.4953 -43.56287,146.46757 -43.56287,149.43984 -43.56287,152.41211 -43.56287,155.38438 -43.56287,158.35665 -43.56287,161.32892 -43.56287,164.30119 -43.56287,167.27346 -43.56287,170.24573 -43.56287,173.218 -43.56287,173.218 -46.238515,173.218 -48.91416,173.218 -51.589805,173.218 -54.26545,173.218 -56.941095,173.218 -59.61674,173.218 -62.292385,173.218 -64.96803,173.218 -67.643675,173.218 -70.31932,170.24573 -70.31932,167.27346 -70.31932,164.30119 -70.31932,161.32892 -70.31932,158.35665 -70.31932,155.38438 -70.31932,152.41211 -70.31932,149.43984 -70.31932,146.46757 -70.31932,143.4953 -70.31932,143.4953 -67.643675,143.4953 -64.96803,143.4953 -62.292385,143.4953 -59.61674,143.4953 -56.941095,143.4953 -54.26545,143.4953 -51.589805,143.4953 -48.91416,143.4953 -46.238515,143.4953 -43.56287))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002240", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9502"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9317379 Foster This project is study of the deep and bottom water formation processes of the antarctic continental shelf off Wilkes Land between 145 deg E longitude and 160 deg E longitude. The project is to be carried out jointly with an Australian oceanographic project. Preliminary work in 1985 has shown that hydrographic sections in this area are quite similar to those of known deep water formation regions in the southern Weddell Sea. This project will include the year-long deployment of six current meter moorings, and tracer studies (oxygen, carbon dioxide, chlorofluorocarbons, stable isotopes, and nutrients) to test whether shelf waves and tides are the principal mechanism for mixing shelf water with the off-shore intermediate water. Two oceanographic cruises are planned for this work: a cruise of the RVIB Nathaniel B. Palmer in February 1995, and a cruise of the Australian ship R/V Aurora Australis in February 1996. ***", "east": 173.218, "geometry": "POINT(158.35665 -56.941095)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.56287, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Foster, Theodore; Foster, Ted", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.31932, "title": "Deep Water Formation off the Eastern Wilkes Land Coast of Antarctica", "uid": "p0000645", "west": 143.4953}, {"awards": "0338248 Takahashi, Taro", "bounds_geometry": "POLYGON((-68.0051 -52.7573,-67.35191 -52.7573,-66.69872 -52.7573,-66.04553 -52.7573,-65.39234 -52.7573,-64.73915 -52.7573,-64.08596 -52.7573,-63.43277 -52.7573,-62.77958 -52.7573,-62.12639 -52.7573,-61.4732 -52.7573,-61.4732 -53.96927,-61.4732 -55.18124,-61.4732 -56.39321,-61.4732 -57.60518,-61.4732 -58.81715,-61.4732 -60.02912,-61.4732 -61.24109,-61.4732 -62.45306,-61.4732 -63.66503,-61.4732 -64.877,-62.12639 -64.877,-62.77958 -64.877,-63.43277 -64.877,-64.08596 -64.877,-64.73915 -64.877,-65.39234 -64.877,-66.04553 -64.877,-66.69872 -64.877,-67.35191 -64.877,-68.0051 -64.877,-68.0051 -63.66503,-68.0051 -62.45306,-68.0051 -61.24109,-68.0051 -60.02912,-68.0051 -58.81715,-68.0051 -57.60518,-68.0051 -56.39321,-68.0051 -55.18124,-68.0051 -53.96927,-68.0051 -52.7573))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001572", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0603"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This proposal is for the continuation and expansion of an underway program on the R/V Laurence M. Gould to measure dissolved carbon dioxide gas (pCO2) along with occasional total carbon dioxide (TCO2) in surface waters on transects of Drake Passage. The added observations include dissolved oxygen, as well as nutrient and carbon-13. The proposed work is similar to the underway measurement program made aboard R/V Nathaniel B. Palmer, and complements similar surface temperature and current data.\u003cbr/\u003eThe Southern Ocean is an important component of the global carbon budget. Low surface temperatures with consequently low vertical stability, ice formation, and high winds produce a very active environment for the exchange of gaseous carbon dioxide between the atmospheric and oceanic reservoirs. The Drake Passage is the narrowest point through which the Antarctic Circumpolar Current and its associated fronts must pass, and is the most efficient location for the measurement of latitudinal gradients of gas exchange. The generated time series will contribute towards two scientific goals: the quantification of the spatial and temporal variability and trends of surface carbon dioxide, oxygen, nutrients and C-13, and an understanding of the dominant processes that contribute to the observed variability.", "east": -61.4732, "geometry": "POINT(-64.73915 -58.81715)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.7573, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Takahashi, Taro", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.877, "title": "Collaborative Research: Processes Driving Spatial and Temporal Variability of Surface pCO2 in the Drake Passage", "uid": "p0000572", "west": -68.0051}, {"awards": "0636975 Sweeney, Colm", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG0909", "datasets": [{"dataset_uid": "002721", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0909", "url": "https://www.rvdata.us/search/cruise/LMG0909"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The proposed project will expand the suite of observations and lengthen the existing time series of underway surface dissolved carbon dioxide (pCO2) measurements transects across the Drake Passage on the R/VIB L.M. Gould. The additional observations include oxygen, nutrients and total CO2 (TCO2) concentrations, and the 13C to 12C ratio of TCO2. The continued and expanded time series will contribute towards two main scientific goals: the quantification of the spatial and temporal variability and the trends of surface carbon dioxide species in four major water mass regimes in the Drake Passage, and the understanding of the dominant processes and changes in those processes that contribute to the variability in surface pCO2 and the resulting air-sea flux of CO2 in the Drake Passage. The expanded program will also include the analysis of the 14C/12C of TCO2 and the specific study of the observations on one short wintertime cruise, with the objective of testing the hypothesis that the dissolved carbon dioxide in surface waters of the Drake Passage is determined by the degree of winter mixing. This is of special significance in light of two scenarios that may be affecting the ventilation of Southern Ocean deep water now and in the future: a decrease in water column stratification with the observations of higher zonal winds, or an increase in stratification due to higher precipitation and warming from climate change. If winter mixing determines the mean annual pCO2 in the Drake Passage, the increasing trend in atmospheric pCO2 should have little effect on sea surface pCO2.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sweeney, Colm; Sweeney, Colm", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Surface pCO2 and the effects of Winter Time Overturning in the Drake Passage", "uid": "p0000872", "west": null}, {"awards": "9317587 Smith, Walker", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP9406", "datasets": [{"dataset_uid": "002582", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP9406", "url": "https://www.rvdata.us/search/cruise/NBP9406"}, {"dataset_uid": "002252", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9406"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "The growing season for phytoplankton in polar oceans is short, but intense. There is an increasing body of evidence that in many Antarctic habitats, the most active period may be very early in the season, a period that has not been emphasized in previous investigations. This project is part of an interdisciplinary program that focuses on the dynamics of the spring phytoplankton bloom in a highly productive subsystem of the Antarctic, the Ross Sea. The overall program will test hypotheses related to the initiation of the phytoplankton bloom shortly after the onset of ice melt, the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions. This component will conduct a set of process-oriented experiments designed to elucidate the controls of phytoplankton productivity, growth and accumulation as well as the mechanisms which control bacterial abundance and productivity in Antarctic waters. Specifically, the relative photosynthetic and nutrient (nitrate, ammonium) characteristics of diatom- vs. Phaeocystis- dominated assemblages will be examined to test if Phaeocystis simply grows faster under spring conditions in the Ross Sea. Phytoplankton and bacterial biomass, productivity and their interactions will be measured to elucidate the complex physical-chemical-biological interactions which occur. Substantial understanding of the mechanisms controlling phytoplankton growth and productivity in spring, the implications and short-term fate of high productivity in spring, and the transition from spring to midsummer conditions will result from this research. Finally, because the Antarctic is the ocean\u0027s largest high-nutrient, low biomass system, and hence has the greatest potential for sequestering carbon dioxide, knowledge of the dynamics of the Ross Sea phytoplankton will also increase our understanding of the carbo n cycle of the Southern Ocean.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Bloom Dynamics and Food Web Structure in the Ross Sea: Primary Productivity, New Production and Bacterial Growth", "uid": "p0000802", "west": null}, {"awards": "0741380 Smith, Walker", "bounds_geometry": "POLYGON((100 -65,106 -65,112 -65,118 -65,124 -65,130 -65,136 -65,142 -65,148 -65,154 -65,160 -65,160 -66.5,160 -68,160 -69.5,160 -71,160 -72.5,160 -74,160 -75.5,160 -77,160 -78.5,160 -80,154 -80,148 -80,142 -80,136 -80,130 -80,124 -80,118 -80,112 -80,106 -80,100 -80,100 -78.5,100 -77,100 -75.5,100 -74,100 -72.5,100 -71,100 -69.5,100 -68,100 -66.5,100 -65))", "dataset_titles": "Small Grants for Exploratory Research - Oceanographic Research in the Amundsen and Ross Seas", "datasets": [{"dataset_uid": "600085", "doi": "10.15784/600085", "keywords": "Amundsen Sea; Chemistry:Fluid; CTD Data; Geochemistry; Oceans; Oden; OSO2007; Sea Surface; Southern Ocean", "people": "Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Small Grants for Exploratory Research - Oceanographic Research in the Amundsen and Ross Seas", "url": "https://www.usap-dc.org/view/dataset/600085"}], "date_created": "Mon, 22 Jun 2009 00:00:00 GMT", "description": "The research will examine the relative importance of the physical and chemical controls on phytoplankton dynamics and carbon flux in continental margin regions of the Southern Ocean, and elucidate mechanisms by which plankton populations and carbon export might be altered by climate change. We specifically will address (1) how the phytoplankton on the continental margins of the southern Ocean respond to spatial and temporal changes in temperature, light, iron supply, and carbon dioxide levels, (2) how these factors initiate changes in phytoplankton assemblage structure, and (3) how carbon export and the efficiency of the biological pump are impacted by the biomass and composition of the phytoplankton. Two regions of study (the Amundsen and Ross Seas) will be investigated, one well studied (Ross Sea) and one poorly described (Amundsen Sea). It is hypothesized that each region will have markedly different physical forcing, giving rise to distinct chemical conditions and therefore biological responses. As such, the comparison of the two may give us insights into the mechanisms of how Antarctic continental margins will respond under changing environmental conditions. Broader impacts include participation by an international graduate student from Brazil, outreach via seminars to the general public, collaboration with the teachers-in-residence on the cruise, development of a cruise web site and interactive email exchanges with local middle school students while at sea", "east": 160.0, "geometry": "POINT(130 -72.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Smith, Walker", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "Small Grants for Exploratory Research - Oceanographic Research in the Amundsen and Ross Seas:", "uid": "p0000217", "west": 100.0}, {"awards": "0742057 Gallager, Scott", "bounds_geometry": "POLYGON((-168.291 -64.846,-165.018 -64.846,-161.745 -64.846,-158.472 -64.846,-155.199 -64.846,-151.926 -64.846,-148.653 -64.846,-145.38 -64.846,-142.107 -64.846,-138.834 -64.846,-135.561 -64.846,-135.561 -66.0269,-135.561 -67.2078,-135.561 -68.3887,-135.561 -69.5696,-135.561 -70.7505,-135.561 -71.9314,-135.561 -73.1123,-135.561 -74.2932,-135.561 -75.4741,-135.561 -76.655,-138.834 -76.655,-142.107 -76.655,-145.38 -76.655,-148.653 -76.655,-151.926 -76.655,-155.199 -76.655,-158.472 -76.655,-161.745 -76.655,-165.018 -76.655,-168.291 -76.655,-168.291 -75.4741,-168.291 -74.2932,-168.291 -73.1123,-168.291 -71.9314,-168.291 -70.7505,-168.291 -69.5696,-168.291 -68.3887,-168.291 -67.2078,-168.291 -66.0269,-168.291 -64.846))", "dataset_titles": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "datasets": [{"dataset_uid": "600086", "doi": "10.15784/600086", "keywords": "Amundsen Sea; Biosphere; Microbiology; Navigation; Oceans; Oden; OSO2007; Sample/Collection Description; Southern Ocean", "people": "Gallager, Scott; Dennett, Mark", "repository": "USAP-DC", "science_program": null, "title": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "url": "https://www.usap-dc.org/view/dataset/600086"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe research will continue and extend the study in the Southern Ocean that was initiated during the Oden Southern Ocean 2006 expedition in collaboration with Swedish scientist Mellissa Chierici. We will quantify carbon flux through the food web in the marginal ice zone (MIZ) by measuring size fractionated primary and secondary production, grazing and carbon flux through nanoplankton (2-20 um), microplankton (20-200um), and mesoplankton (200-2000 um). Community structure, species abundance and size specific grazing rates will be quantified using a variety of techniques both underway and at ice stations along the MIZ. The proposed cruise track extends across the Drake Passage to the Western Antarctic Peninsula (WAP) with three station transects along a gradient from the open ocean through the marginal ice zone (MIZ) in the Bellinghausen and Amundsen Seas and into the Ross Sea Polynya. Ice stations along each transect will provide material to characterize production associated with annual ice. Underway measurements of primary and secondary production (chlorophyll, CDOM, microplankton, and mesoplankton) and hydrography (temperature, salinity, pH, DO, turbidity) will establish a baseline for future cruises and as support for other projects such as biogeochemical studies on carbon dioxide drawdown and trace metal work on primary production. The outcome of these measurements will be a description of nano to mesoplankton standing stocks, community structure, and carbon flux along the MIZ in the Bellinghausen and Amundsen Seas and the Ross Sea Polynya.", "east": -135.561, "geometry": "POINT(-151.926 -70.7505)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.846, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gallager, Scott; Dennett, Mark", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.655, "title": "SGER: Primary and Secondary Production and Carbon Flux Through the Microbial Community Along the Western Antarctic Marginal Ice Zone on the Oden Southern Ocean 2007 Expeditions", "uid": "p0000563", "west": -168.291}, {"awards": "0741403 Sherrell, Robert", "bounds_geometry": "POLYGON((-180 -69,-172.5 -69,-165 -69,-157.5 -69,-150 -69,-142.5 -69,-135 -69,-127.5 -69,-120 -69,-112.5 -69,-105 -69,-105 -69.9,-105 -70.8,-105 -71.7,-105 -72.6,-105 -73.5,-105 -74.4,-105 -75.3,-105 -76.2,-105 -77.1,-105 -78,-112.5 -78,-120 -78,-127.5 -78,-135 -78,-142.5 -78,-150 -78,-157.5 -78,-165 -78,-172.5 -78,180 -78,178.8 -78,177.6 -78,176.4 -78,175.2 -78,174 -78,172.8 -78,171.6 -78,170.4 -78,169.2 -78,168 -78,168 -77.1,168 -76.2,168 -75.3,168 -74.4,168 -73.5,168 -72.6,168 -71.7,168 -70.8,168 -69.9,168 -69,169.2 -69,170.4 -69,171.6 -69,172.8 -69,174 -69,175.2 -69,176.4 -69,177.6 -69,178.8 -69,-180 -69))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 10 Mar 2009 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThe research objective is (1) to determine the distributions and dynamics of a full suite of bioactive trace metals in dissolved and suspended particulate forms, along sampling transects of the Amundsen and Ross Seas. And (2) to test the sensitivity of overall cellular metal stoichiometry (metal/carbon ratios) to natural gradients in species assemblage and Fe availability. Our earlier findings from a single Ross Sea station and from a Drake Passage crossing suggest that Fe-limited phytoplankton cells are unusually enriched in Zn, Cu and Cd relative to biomass carbon, with strong implications for the biogeochemical cycling of these elements relative to carbon fluxes in the Southern Ocean. In collaboration with other researchers on the cruise, we will also measure metal stoichiometry of cells exposed to predicted 2010 temperature and carbon dioxide levels in shipboard incubation studies, as a window into possible effects of climate change on metals biogeochemistry in these regions. This proposal will support close international collaborations and lasting infrastructure development as US and Swedish scientists, and more importantly, their students, work toward shared the shared goal of understanding a region that is experiencing one of the fastest rates of climate change on the globe. Trace metal micro-nutrients are a key control on the productivity of Antarctic marine ecosystems. Our results will be made widely available through research publications and internet-available databases, and public outreach through COSEE at Rutgers University.", "east": -105.0, "geometry": "POINT(-148.5 -73.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -69.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Sherrell, Robert", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -78.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden: Bioactive trace metals in the Amundsen and Ross Seas", "uid": "p0000561", "west": 168.0}, {"awards": "0440615 Brook, Edward; 0440498 White, James; 0440602 Saltzman, Eric; 0440759 Sowers, Todd; 0440701 Severinghaus, Jeffrey; 0440509 Battle, Mark", "bounds_geometry": "POINT(-112.085 -79.467)", "dataset_titles": "Gases in Firn Air and Shallow Ice at the WAIS Drilling Site, Antarctica; Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core; Methane Isotopes from the WAIS Divide Ice Core; Surface Temperature Reconstruction from Borehole Temperature Measurement in WDC05A; WAIS ice core Methane Data, Carbon Dioxide Data", "datasets": [{"dataset_uid": "601357", "doi": "10.15784/601357", "keywords": "Antarctica; Atmospheric Gases; Cryosphere; gas measurement; Ice Core; Ice Core Gas Records; Trace Gases", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core", "url": "https://www.usap-dc.org/view/dataset/601357"}, {"dataset_uid": "609638", "doi": "10.7265/N56971HF", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Temperature; WAIS divide; WAIS Divide Ice Core", "people": "Orsi, Anais J.; Severinghaus, Jeffrey P.", "repository": "USAP-DC", "science_program": null, "title": "Surface Temperature Reconstruction from Borehole Temperature Measurement in WDC05A", "url": "https://www.usap-dc.org/view/dataset/609638"}, {"dataset_uid": "609493", "doi": "10.7265/N5319SV3", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Brook, Edward J.; Sowers, Todd A.; Taylor, Kendrick C.; McConnell, Joseph; Mitchell, Logan E", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS ice core Methane Data, Carbon Dioxide Data", "url": "https://www.usap-dc.org/view/dataset/609493"}, {"dataset_uid": "609435", "doi": "10.7265/N5J67DW0", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; Methane; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Methane Isotopes from the WAIS Divide Ice Core", "url": "https://www.usap-dc.org/view/dataset/609435"}, {"dataset_uid": "609412", "doi": "10.7265/N5251G40", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Snow/Ice; WAIS divide; WAIS Divide Ice Core", "people": "Saltzman, Eric", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Gases in Firn Air and Shallow Ice at the WAIS Drilling Site, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609412"}], "date_created": "Tue, 03 Feb 2009 00:00:00 GMT", "description": "This award supports a project to measure the elemental and isotopic composition of firn air and occluded air in shallow boreholes and ice cores from the WAIS Divide site, the location of a deep ice-coring program planned for 2006-07 and subsequent seasons. The three primary objectives are: 1) to establish the nature of firn air movement and trapping at the site to aid interpretations of gas data from the deep core; 2) to expand the suite of atmospheric trace gas species that can be measured in ice and replicate existing records of other species; and 3) to inter-calibrate all collaborating labs to insure that compositional and isotopic data sets are inter-comparable. The program will be initiated with a shallow drilling program during the 05/06 field season which will recover two 300+m cores and firn air samples. The ice core and firn air will provide more than 700 years of atmospheric history that will be used to address a number of important questions related to atmospheric change over this time period. The research team consists of six US laboratories that also plan to participate in the deep core program. This collaborative research program has a number of advantages. First, the scientists will be able to coordinate sample allocation a priori to maximize the resolution and overlap of records of interrelated species. Second, sample registration will be exact, allowing direct comparison of all records. Third, a coherent data set will be produced at the same time and all PI.s will participate in interpreting and publishing the results. This will insure that the best possible understanding of gas records at the WAIS Divide site will be achieved, and that all work necessary to interpret the deep core is conducted in a timely fashion. The collaborative structure created by the proposal will encourage sharing of techniques, equipment, and ideas between the laboratories. The research will identify impacts of various industrial/agricultural activities and help to distinguish them from natural variations, and will include species for which there are no long records of anthropogenic impact. The work will also help to predict future atmospheric loadings. The project will contribute to training scientists at several levels, including seven undergraduates, two graduate students and one post doctoral fellow.", "east": -112.085, "geometry": "POINT(-112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GC-MS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e SPECTROMETERS \u003e SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e THERMISTORS \u003e THERMISTORS", "is_usap_dc": true, "keywords": "Ice Core Chemistry; Firn; LABORATORY; Ice Core; Firn Air Isotope Measurements; Shallow Firn Air; FIELD INVESTIGATION; Ice Core Gas Records; GROUND-BASED OBSERVATIONS; Firn Isotopes; gas data; Polar Firn Air; Not provided; Trapped Gases; West Antarctic Ice Sheet; Ice Sheet; Gas; deep core; Firn Air Isotopes; AGDC-project; WAIS Divide-project; FIELD SURVEYS; bore hole; NSIDC \u003e National Snow and Ice Data Center; Atmospheric Gases; Isotope; trace gas species; Ice Core Data; Surface Temperatures; Firn Air; isotopic; air samples; Atmospheric; cores; NSIDC; AGDC; WAIS divide; Antarctica", "locations": "West Antarctic Ice Sheet; Antarctica; WAIS divide", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE; PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Battle, Mark; Mischler, John; Saltzman, Eric; Aydin, Murat; White, James; Brook, Edward J.; Orsi, Anais J.; Severinghaus, Jeffrey P.; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Collaborative Research: Gases in Firn Air and Shallow Ice at the Proposed WAIS Divide Drilling Site", "uid": "p0000368", "west": -112.085}, {"awards": "0230268 Anderson, Robert", "bounds_geometry": "POLYGON((-180 -50,-169 -50,-158 -50,-147 -50,-136 -50,-125 -50,-114 -50,-103 -50,-92 -50,-81 -50,-70 -50,-70 -51.5,-70 -53,-70 -54.5,-70 -56,-70 -57.5,-70 -59,-70 -60.5,-70 -62,-70 -63.5,-70 -65,-81 -65,-92 -65,-103 -65,-114 -65,-125 -65,-136 -65,-147 -65,-158 -65,-169 -65,180 -65,177 -65,174 -65,171 -65,168 -65,165 -65,162 -65,159 -65,156 -65,153 -65,150 -65,150 -63.5,150 -62,150 -60.5,150 -59,150 -57.5,150 -56,150 -54.5,150 -53,150 -51.5,150 -50,153 -50,156 -50,159 -50,162 -50,165 -50,168 -50,171 -50,174 -50,177 -50,-180 -50))", "dataset_titles": "Southern Ocean Deglacial Opal, Radionuclide, and Diatom Upwelling Data", "datasets": [{"dataset_uid": "000199", "doi": "", "keywords": null, "people": null, "repository": "NCEI", "science_program": null, "title": "Southern Ocean Deglacial Opal, Radionuclide, and Diatom Upwelling Data", "url": "https://www.ncdc.noaa.gov/paleo/study/8439"}], "date_created": "Mon, 12 Jan 2009 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the \"Silicic Acid Leakage Hypothesis\" as it relates to global carbon dioxide fluctuations during glacial-interglacial cycles.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit\u003cbr/\u003eThis project will evaluate the burial rate of biogenic opal in the Pacific sector of the Southern Ocean, both during the Last Glacial Maximum (LGM) and during the Holocene, as a critical test of the \"Silicic Acid Leakage Hypothesis\". \u003cbr/\u003e\u003cbr/\u003eThe \"Silicic Acid Leakage Hypothesis\" has been proposed recently to explain the glacial reduction in the carbon dioxide content of the atmosphere that has been reconstructed from Antarctic ice cores. Vast amounts of dissolved Si (silicic acid) are supplied to surface waters of the Southern Ocean by wind-driven upwelling of deep waters. Today, that dissolved Si is consumed almost quantitatively by diatoms who form skeletal structures composed of biogenic opal (a mineral form of silicon). According to the \"Silicic Acid Leakage Hypothesis\", environmental conditions in the Southern Ocean during glacial periods were unfavorable for diatom growth, leading to reduced (compared to interglacials) efficiency of dissolved Si utilization. Dissolved Si that was not consumed biologically in the glacial Southern ocean was then exported to the tropics in waters that sink in winter to depths of a few hundred meters along the northern fringes of the Antarctic Circumpolar Current, and return some decades later to the sunlit surface in tropical regions of wind-driven upwelling. \u003cbr/\u003e\u003cbr/\u003eAn increase in the amount of dissolved Si that \"leaks\" out of the Southern Ocean and later upwells at low latitudes could shift the global average composition of phytoplankton toward a greater abundance of diatoms and fewer CaCO3-secreting taxa (especially coccolithophorids). Consequences of such a taxonomic shift in the ocean\u0027s phytoplankton assemblage include:\u003cbr/\u003e a) an increase in the global average organic carbon/calcium carbonate ratio of particulate biogenic material sinking into the deep sea;\u003cbr/\u003e b) a reduction in the preservation and burial of calcium carbonate in marine sediments;\u003cbr/\u003e c) an increase in ocean alkalinity as a consequence of the first two changes mentioned above, and;\u003cbr/\u003e d) a lowering of atmospheric CO2 concentrations in response to increased alkalinity of ocean waters. \u003cbr/\u003e\u003cbr/\u003eA complete assessment of the Silicic acid leakage hypothesis will require an evaluation of: (1) Si utilization efficiencies using newly-developed stable isotopic techniques; (2) opal burial rates in low-latitude upwelling regions; and (3) opal burial rates in the Southern Ocean. This project addresses the last of these topics. \u003cbr/\u003e\u003cbr/\u003ePrevious work has shown that there was little change in opal burial rate between the LGM and the Holocene in the Atlantic and Indian sectors of the Southern Ocean. Preliminary results (summarized in this proposal) suggest that the Pacific may have been different, however, in that opal burial rates in the Pacific sector seem to have been lower during the LGM than during the Holocene, allowing for the possibility of \"Si leakage\" from this region. However, available results are too sparse to make any quantitative conclusions at this time. For that reason, we propose to make a comprehensive evaluation of opal burial rates in the Pacific sector of the Southern Ocean. \u003cbr/\u003e\u003cbr/\u003eSignificance and Broader Impacts\u003cbr/\u003eDetermining the mechanism(s) by which the ocean has regulated climate-related changes in the CO2 content of the atmosphere has been the focus of a substantial effort by paleoceanographers over the past two decades. The Silicic Acid Leakage Hypothesis is a viable new candidate mechanism that warrants further exploration and testing. Completion of the proposed work will contribute significantly to that effort. \u003cbr/\u003e\u003cbr/\u003eDuring the course of this work, several undergraduates will be exposed to paleoclimate research through their involvement in this project. Burckle and Anderson are both dedicated to the education and training of young scientists, and to the recruitment of women and under-represented minorities. To illustrate, two summer students (undergraduates) worked in Burckle\u0027s lab during the summer of 2002. One was a woman and the other (male) was a member of an under-represented minority. Anderson and Burckle will continue with similar recruitment efforts during the course of the proposed study. A minority student who has expressed an interest in working on this research during the summer of 2003 has already been identified.", "east": -70.0, "geometry": "POINT(-140 -57.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -50.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Anderson, Robert; Burckle, Lloyd", "platforms": "Not provided", "repo": "NCEI", "repositories": "NCEI", "science_programs": null, "south": -65.0, "title": "Opal Burial in the Pacific Sector of the Southern Ocean: A Test of the \"Silicic Acid Leakage Hypothesis.\"", "uid": "p0000457", "west": 150.0}, {"awards": "0741428 Hutchins, David", "bounds_geometry": "POINT(-106 -73)", "dataset_titles": null, "datasets": null, "date_created": "Sun, 23 Nov 2008 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003eThis Small Grants for Exploratory Research (SGER) proposal describes global change-related experimental research designed to take full advantage of a unique science opportunity on short notice, the leasing of the Oden to conduct ice-breaking operations in McMurdo Sound. \u003cbr/\u003e\u003cbr/\u003eOur emphasis will be on using this opportunistic research platform to ask two questions about present day and future controls on Antarctic margin phytoplankton communities. These are: 1. How will expected alterations in pCO2, pH, and Fe availability in the Southern Ocean, due to future anthropogenic climate change affect phytoplankton species assemblages, carbon and nutrient biogeochemistry, and remineralization processes? 2. What is the current role of organic co-factors (vitamins) in limiting or co-limiting (along with iron ) phytoplankton growth and production in the Antarctic margin? The research approach includes experimental incubations with variation in iron enrichment, carbon dioxide concentration, and temperature. A second suite of experiments will examine co-limitation effects between vitamin B12 and Fe and B12 uptake kinetics. Changes in phytoplankton community structure, and carbon and nutrient cycling will be determined, in collaboration with many of the participating U.S. and Swedish investigators. Together, these two main objectives should allow us to obtain novel insights into the current and future controls on Antarctic margin phytoplankton growth, productivity, and carbon and nutrient biogeochemistry. In particular, the experiments in the Amundsen Sea represent a one-of-a-kind opportunity to understand algal dynamics and potential future responses to climate change in this little-studied ecosystem, and compare these results to those from the better-known Ross Sea. An important result of this study will be to build strong international collaborations with the Swedish marine science community. Additional broader impacts include participatin of an Hispanic Ph.D. student in cruise work and post-cruise analyses, and integration of results into graduate courses at the USC Catalina Lab facility. Public outreach will include presentations on global change impacts on the ocean targeted at audiences ranging from legislators and policymakers to the general public.", "east": -106.0, "geometry": "POINT(-106 -73)", "instruments": null, "is_usap_dc": true, "keywords": "SHIPS", "locations": null, "north": -73.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Hutchins, David", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repositories": null, "science_programs": null, "south": -73.0, "title": "SGER: Science-of-Opportunity Aboard Icebreaker Oden - Phytoplankton Global Change Experiments and Vitamin/Iron Co-Limitation in the Amundsen and Ross Seas", "uid": "p0000224", "west": -106.0}, {"awards": "0126194 Harder, Susan", "bounds_geometry": null, "dataset_titles": "Access to data", "datasets": [{"dataset_uid": "001336", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Access to data", "url": "http://nsidc.org/data/agdc_investigators.html"}], "date_created": "Tue, 20 Feb 2007 00:00:00 GMT", "description": "This award supports a two-year project to continue work developing the techniques to make carbon monoxide (CO) measurements in ice core samples. Carbon monoxide is an important atmospheric chemical constituent as it is a primary sink for hydroxyl radical (OH) (and therefore influences the oxidizing capacity of the atmosphere) and because the concentrations of three major greenhouses gases , carbon dioxide (CO2), methane (CH4) and ozone (O3) are directly tied to the concentration of CO. In light of recent anthropogenic increases in the emissions of CO, CO2, CH4 and NOx, it is desirable to understand this complex chemical system and the changes in the greenhouse forcing resulting from perturbation. Because it is difficult to test the accuracy of models for past and future conditions for which no direct atmospheric measurements of trace gas concentrations are available these measurements must be obtained in other ways. Polar ice cores provide a means to make these measurements. Further work is necessary to refine the analytical technique and additional measurements are necessary to investigate the accuracy of these results and to establish the nature of temporal trends in CO. It is anticipated that the CO record, combined with existing or new data for CO2, CH4 , N2O and other paleoclimate variables, will provide further constraints on model studies of the effect of changing atmospheric chemistry on greenhouse forcing.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Harder, Susan", "platforms": "Not provided", "repo": "NSIDC", "repositories": "NSIDC", "science_programs": null, "south": null, "title": "Ice Core Records of Atmospheric Carbon Monoxide", "uid": "p0000706", "west": null}, {"awards": "0125468 Severinghaus, Jeffrey", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 01 Feb 2005 00:00:00 GMT", "description": "This award supports the continued measurements of gas isotopes in the Vostok ice core, from Antarctica. One objective is to identify the phasing of carbon dioxide variations and temperature variations, which may place constraints on hypothesized cause and effect relationships. Identification of phasing has in the past been hampered by the large and uncertain age difference between the gases trapped in air bubbles and the surrounding ice. This work will circumvent this issue by employing an indicator of temperature in the gas phase. It is argued that 40Ar/39Ar behaves as a qualitative indicator of temperature, via an indirect relationship between temperature, accumulation rate, firn thickness, and gravitational fractionation of the gas isotopes. The proposed research will make nitrogen and argon isotope measurements on ~ 200 samples of ice covering Termination II (130,000 yr B.P.) and Termination IV (340,000 yr BP). The broader impacts may include a better understanding of the role of atmospheric carbon dioxide concentrations in climate change.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Vostok; Isotope; Ice Core; Not provided", "locations": "Vostok", "north": -62.83, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "Argon and nitrogen isotope measurements in the Vostok ice core as aconstraint on phasing of CO2 and temperature changes", "uid": "p0000752", "west": -180.0}, {"awards": "9980691 Wahlen, Martin", "bounds_geometry": null, "dataset_titles": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "datasets": [{"dataset_uid": "609202", "doi": "10.7265/N5N877Q9", "keywords": "Antarctica; Chemistry:Fluid; CO2; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "people": "Wahlen, Martin; Ahn, Jinho; Deck, Bruce", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609202"}], "date_created": "Thu, 11 Dec 2003 00:00:00 GMT", "description": "9980691\u003cbr/\u003eWahlen\u003cbr/\u003e\u003cbr/\u003eThis award is for support for three years of funding to reconstruct the atmospheric carbon dioxide (CO2) and carbon-13 isotope (d13C) concentration in ice cores from Antarctica over several climatic periods. Samples from the Holocene, the Last Glacial Maximum (LGM)-Holocene transition and glacial stadial/interstadial episodes will be examined. Samples from the Siple Dome ice core drilled in 1998/99 will be made, in addition to measurements from the Taylor Dome and Vostok ice cores. The major objectives are to investigate the phase relationships between variations in the concentration of atmospheric CO2, its carbon isotope composition, and temperature changes (indicated by 18dO and dD of the ice) during deglaciations as well as across rapid climate change events (e.g. Dansgaard-Oeschger events). This will help to determine systematic changes in the global carbon cycle during and between different climatic periods, and to ascertain if the widely spread northern hemisphere temperature stadial/interstadial events produced a global atmospheric carbon dioxide signal. Proven experimental techniques will be used.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Siple Dome; Ice Core; USAP-DC; Carbon Dioxide", "locations": "Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Wahlen, Martin; Ahn, Jinho; Deck, Bruce", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "CO2 and Delta 13CO2 in Antarctic Ice Cores", "uid": "p0000166", "west": null}, {"awards": "9615292 Wahlen, Martin", "bounds_geometry": null, "dataset_titles": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum; Taylor Dome Ice Core Chemistry, Ion, and Isotope Data", "datasets": [{"dataset_uid": "609246", "doi": "", "keywords": "Antarctica; Chemistry:Ice; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Ice Core Records; Isotope; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Steig, Eric J.; Mayewski, Paul A.; Indermuhle, A.; Sowers, Todd A.; Smith, Jesse; Brook, Edward J.", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Taylor Dome Ice Core Chemistry, Ion, and Isotope Data", "url": "https://www.usap-dc.org/view/dataset/609246"}, {"dataset_uid": "609108", "doi": "10.7265/N54F1NN5", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Taylor Dome; Taylor Dome Ice Core", "people": "Wahlen, Martin", "repository": "USAP-DC", "science_program": null, "title": "Carbon-Isotopic Composition of Atmospheric CO2 since the Last Glacial Maximum", "url": "https://www.usap-dc.org/view/dataset/609108"}], "date_created": "Tue, 01 Jan 2002 00:00:00 GMT", "description": "This award is for support of a program to reconstruct the record of atmospheric carbon dioxide (and the carbon-13 isotopes of carbon dioxide) over several intervals, including the Last Glacial Maximum-Holocene transition, interstadial episodes, the mid-Holocene, the last 1000 years and the penultimate glacial period, using ice from the Taylor Dome and Vostok ice cores. The major objective of this study is to investigate the phase relationship between variations of the greenhouse gases occluded in the ice cores and temperature changes (indicated by oxygen and deuterium isotopes) during the last deglaciation. In addition, the concentration of atmospheric carbon dioxide over the past 1000 years and during the mid-Holocene will be determined in these cores.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "USAP-DC; Ice Core; isotopes; GROUND-BASED OBSERVATIONS; Carbon; Trapped Gases; Glaciology; GROUND STATIONS; Taylor Dome; Carbon Dioxide; Antarctica; Nitrogen", "locations": "Antarctica; Taylor Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.; Wahlen, Martin; Smith, Jesse; Brook, Edward J.; Indermuhle, A.; Mayewski, Paul A.; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": null, "title": "Carbon Dioxide and Carbon Isotopes in the Taylor Dome and Vostok Ice Cores", "uid": "p0000153", "west": null}]

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