USAP-DC

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

[{"awards": "2135695 Emslie, Steven; 2135696 Polito, Michael", "bounds_geometry": "POLYGON((-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70,-180 -70.8,-180 -71.6,-180 -72.4,-180 -73.2,-180 -74,-180 -74.8,-180 -75.6,-180 -76.4,-180 -77.2,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,-180 -78,180 -78,178 -78,176 -78,174 -78,172 -78,170 -78,168 -78,166 -78,164 -78,162 -78,160 -78,160 -77.2,160 -76.4,160 -75.6,160 -74.8,160 -74,160 -73.2,160 -72.4,160 -71.6,160 -70.8,160 -70,162 -70,164 -70,166 -70,168 -70,170 -70,172 -70,174 -70,176 -70,178 -70,-180 -70))", "dataset_titles": "Stable isotopes of Adelie Penguin chick bone collagen", "datasets": [{"dataset_uid": "601913", "doi": "10.15784/601913", "keywords": "Adelie Penguin; Antarctica; Cryosphere; Foraging; Polynya; Pygoscelis Adeliae; Ross Sea; Stable Isotopes", "people": "Powers, Shannon; Emslie, Steven D.; Reaves, Megan", "repository": "USAP-DC", "science_program": null, "title": "Stable isotopes of Adelie Penguin chick bone collagen", "url": "https://www.usap-dc.org/view/dataset/601913"}], "date_created": "Fri, 28 Oct 2022 00:00:00 GMT", "description": "The Ad\u00e9lie penguin (Pygoscelis adeliae) is the most abundant penguin in Antarctica, though its populations are currently facing threats from climate change, loss of sea ice habitat and food supplies. In the Ross Sea region, the cold, dry environment has allowed preservation of Ad\u00e9lie penguin bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (more than 45,000 years ago) to the present. A warming period at 4,000-2,000 years ago, known as the penguin \u2018optimum\u2019, reduced sea ice extent and allowed this species to access and reproduce in the southern Ross Sea. This coastline likely will be reoccupied in the future as marine conditions change with current warming trends. This project will investigate ecological responses in diet and foraging behavior of the Ad\u00e9lie penguin using well-preserved bones and other tissues that date from before, during and after the penguin \u2018optimum\u2019. The Principal investigators will collect and analyze bones, feathers and eggshells from colonies in the Ross Sea to determine changes in population size and feeding locations over millennia. Most of these colonies are associated with highly productive areas of open water surrounded by sea ice. Current warming trends are causing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Ad\u00e9lie penguins and their foraging grounds in this region from human impacts and knowledge on how this species has responded to climate change in the past will support this goal. This project benefits NSF\u2019s mission to expand fundamental knowledge of Antarctic systems, biota, and processes. In association with their research program, the Principal Investigators will create undergraduate opportunities for research-driven coursework, will design K-12 curriculum and assess the effectiveness of these activities. Two graduate students will be supported by this project to update and refine the curricula working with K-12 teachers. There is also training and partial support included for one doctorate, two master and eight undergraduate students. General public will be reached through social media and YouTube channel productions. A suite of three stable isotopes (carbon, nitrogen, and sulfur) will be analyzed in Adelie penguin bones and feathers from active and abandoned colonies to assess ecological shifts through time. Stable isotope analyses of carbon and nitrogen (\u03b413C and \u03b415N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. Sulfur (\u03b434S) is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. Using these three isotopes from collagen, ancient and modern penguin colonies will be investigated in the southern, central and northern Ross Sea to determine changes in populations and foraging locations over millennia. Most of these colonies are associated with one of three polynyas in the Ross Sea. This study will be the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today. Results from this project will also inform management on best practices for Adelie penguin conservation affected by climate change. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -180.0, "geometry": "POINT(170 -74)", "instruments": null, "is_usap_dc": true, "keywords": "Climate Change; Adelie Penguin; Foraging Ecology; Ross Sea; PENGUINS; Holocene; Stable Isotopes", "locations": "Ross Sea", "north": -70.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Lane, Chad S; Polito, Michael", "platforms": null, "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea", "uid": "p0010388", "west": 160.0}, {"awards": "1937546 Morgan-Kiss, Rachael; 1937595 Briggs, Brandon", "bounds_geometry": "POLYGON((162 -77.616667,162.1 -77.616667,162.2 -77.616667,162.3 -77.616667,162.4 -77.616667,162.5 -77.616667,162.6 -77.616667,162.7 -77.616667,162.8 -77.616667,162.9 -77.616667,163 -77.616667,163 -77.6283336,163 -77.6400002,163 -77.6516668,163 -77.6633334,163 -77.67500000000001,163 -77.68666660000001,163 -77.69833320000001,163 -77.7099998,163 -77.7216664,163 -77.733333,162.9 -77.733333,162.8 -77.733333,162.7 -77.733333,162.6 -77.733333,162.5 -77.733333,162.4 -77.733333,162.3 -77.733333,162.2 -77.733333,162.1 -77.733333,162 -77.733333,162 -77.7216664,162 -77.7099998,162 -77.69833320000001,162 -77.68666660000001,162 -77.67500000000001,162 -77.6633334,162 -77.6516668,162 -77.6400002,162 -77.6283336,162 -77.616667))", "dataset_titles": "18S rRNA from McMurdo Dry Valley lakes", "datasets": [{"dataset_uid": "200436", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "18S rRNA from McMurdo Dry Valley lakes", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA1125919/"}], "date_created": "Wed, 27 Jul 2022 00:00:00 GMT", "description": "Part I: Non-technical description: Microbial communities are of more than just a scientific curiosity. Microbes represent the single largest source of evolutionary and biochemical diversity on the planet. They are the major agents for cycling carbon, nitrogen, phosphorus, and other elements through the ecosystem. Despite their importance in ecosystem function, microbes are still generally overlooked in food web models and nutrient cycles. Moreover, microbes do not live in isolation: their growth and metabolism are influenced by complex interactions with other microorganisms. This project will focus on the ecology, activity and roles of microbial communities in Antarctic Lake ecosystems. The team will characterize the genetic underpinnings of microbial interactions and the influence of environmental gradients (e.g. light, nutrients, oxygen, sulfur) and seasons (e.g. summer vs. winter) on microbial networks in Lake Fryxell and Lake Bonney in the Taylor Valley within the McMurdo Dry Valley region. Finally, the project furthers the NSF goals of training new generations of scientists by including undergraduate and graduate students, a postdoctoral researcher and a middle school teacher in both lab and field research activities. This partnership will involve a number of other outreach training activities, including visits to classrooms and community events, participation in social media platforms, and webinars. Part II: Technical description: Ecosystem function in the extreme Antarctic Dry Valleys ecosystem is dependent on complex biogeochemical interactions between physiochemical environmental factors (e.g. light, nutrients, oxygen, sulfur), time of year (e.g. summer vs. winter) and microbes. Microbial network complexity can vary in relation to specific abiotic factors, which has important implications on the fragility and resilience of ecosystems under threat of environmental change. This project will evaluate the influence of biogeochemical factors on microbial interactions and network complexity in two Antarctic ice-covered lakes. The study will be structured by three main objectives: 1) infer positive and negative interactions from rich spatial and temporal datasets and investigate the influence of biogeochemical gradients on microbial network complexity using a variety of molecular approaches; 2) directly observe interactions among microbial eukaryotes and their partners using flow cytometry, single-cell sorting and microscopy; and 3) develop metabolic models of specific interactions using metagenomics. Outcomes from amplicon sequencing, meta-omics, and single-cell genomic approaches will be integrated to map specific microbial network complexity and define the role of interactions and metabolic activity onto trends in limnological biogeochemistry in different seasons. These studies will be essential to determine the relationship between network complexity and future climate conditions. Undergraduate researchers will be recruited from both an REU program with a track record of attracting underrepresented minorities and two minority-serving institutions. To further increase polar literacy training and educational impacts, the field team will include a teacher as part of a collaboration with the successful NSF-funded PolarTREC program and participation in activities designed for public outreach. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 163.0, "geometry": "POINT(162.5 -77.67500000000001)", "instruments": null, "is_usap_dc": true, "keywords": "MICROALGAE; AQUATIC ECOSYSTEMS; Antarctica; LAKE/POND; BACTERIA/ARCHAEA; COMMUNITY DYNAMICS", "locations": "Antarctica", "north": -77.616667, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Morgan-Kiss, Rachael; Briggs, Brandon", "platforms": null, "repo": "NCBI SRA", "repositories": "NCBI SRA", "science_programs": null, "south": -77.733333, "title": "ANT LIA: Collaborative Research: Genetic Underpinnings of Microbial Interactions in Chemically Stratified Antarctic Lakes", "uid": "p0010355", "west": 162.0}, {"awards": "1851022 Fudge, Tyler; 1851094 Baker, Ian", "bounds_geometry": null, "dataset_titles": "Code for calculating mean gradient for EDC sulfate data; EPICA Dome C Sulfate Data 7-3190m; Forward Diffusion Model used to calculate widening of volcanic layer widths; Volcanic Widths in Dome C Interglacials and Glacials", "datasets": [{"dataset_uid": "601855", "doi": "10.15784/601855", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Volcanic Widths in Dome C Interglacials and Glacials", "url": "https://www.usap-dc.org/view/dataset/601855"}, {"dataset_uid": "601759", "doi": "10.15784/601759", "keywords": "Antarctica", "people": "Fudge, T. J.; Severi, Mirko", "repository": "USAP-DC", "science_program": "COLDEX", "title": "EPICA Dome C Sulfate Data 7-3190m", "url": "https://www.usap-dc.org/view/dataset/601759"}, {"dataset_uid": "601857", "doi": "10.15784/601857", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Forward Diffusion Model used to calculate widening of volcanic layer widths", "url": "https://www.usap-dc.org/view/dataset/601857"}, {"dataset_uid": "601856", "doi": "10.15784/601856", "keywords": "Antarctica; Cryosphere", "people": "Fudge, T. J.", "repository": "USAP-DC", "science_program": null, "title": "Code for calculating mean gradient for EDC sulfate data", "url": "https://www.usap-dc.org/view/dataset/601856"}], "date_created": "Mon, 28 Jun 2021 00:00:00 GMT", "description": "The ice of the polar ice sheets is among the purest substances on Earth, yet the small amount of impurities --such as acids-- are important to how the ice flows and what can be learned from ice cores about past climate. The goal of this project is to understand the role of such acids on the deformation of polycrystalline ice by comparing the deformation behavior of pure and sulfuric acid-doped samples. Sulfuric acid was chosen both because of its importance for interpreting past climate and because it can lead to water veins in ice at low temperatures. This work will focus on the location, movement, and impact of acids in polycrystalline ice that are more complex than in single crystals of ice. By deforming samples and performing microstructural characterization, the role of acids on deformation rate, grain evolution, and the movement of the acids themselves, will be assessed. The work will lead to the education of a Ph.D. student at Dartmouth College, introduce undergraduate students to research at both the University of Washington and Dartmouth College. Despite the ubiquitous use of the constitutive relation for ice commonly referred to as \"Glen\u0027s Flow Law\", significant uncertainty exists particularly with regard to the role of impurities and the development of oriented fabrics. The aim of this project is to improve the constitutive relationship for ice by performing deformation tests and microstructural characterization of pure and sulfuric acid-doped ice. The project will focus on sulfuric acid\u0027s impact on ice viscosity, fabric evolution, and diffusivity. Sulfuric acid can have both direct and indirect effects on the mechanical properties of polycrystalline ice. The direct effects change the dislocation velocity and/or density, and the indirect effects change the grain size and fabric. The complexity and interaction of these effects means that it is not possible to understand the effects of sulfuric acid by simply examining ice core specimens. In this project, the team will deform four types of ice: lab-grown ice samples doped with similar-to-natural concentrations of sulfuric acid, lab-grown high-purity ice, layered doped and pure ice, and natural ice from Antarctic ice cores. Deformation will be performed in both uniaxial compression and simple shear. The addition of simple shear tests is critical for relating the laboratory-observed deformation behavior to the behavior of polar ice sheets where the shear strain dominates ice motion in basal ice. After deformation to strains from 5 percent up to 25 percent, the microstructural development will be assessed with methods including a variety of scanning electron microscope techniques, Raman microscopy, synchrotron-based Nano-X-ray fluorescence, and ion chromatography. These analysis techniques will allow the determination of 1) the segregation and movement of impurities, 2) the rate of grain-boundary migration, 3) the number of recrystallized grains; and 4) the full orientation of the ice crystals. The results will enable both microstructural modeling of the effects of sulfuric acid and numerical modeling of diffusion in ice cores. The net result will be a better understanding of ice deformation that improves ice-core interpretation and ice-sheet modeling. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "AMD; Polycrystalline Ice; LABORATORY; Epica Dome C; SNOW/ICE; USA/NSF; USAP-DC; Ice Core; Amd/Us", "locations": "Epica Dome C", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Science and Technology; Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian; Fudge, T. J.", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Impact of Impurities and Stress State on Polycrystalline Ice Deformation", "uid": "p0010211", "west": null}, {"awards": "1643494 Saal, Alberto", "bounds_geometry": "POLYGON((-68.074 -57.345,-66.6033 -57.345,-65.1326 -57.345,-63.6619 -57.345,-62.1912 -57.345,-60.7205 -57.345,-59.2498 -57.345,-57.7791 -57.345,-56.3084 -57.345,-54.8377 -57.345,-53.367 -57.345,-53.367 -58.12517,-53.367 -58.90534,-53.367 -59.68551,-53.367 -60.46568,-53.367 -61.24585,-53.367 -62.02602,-53.367 -62.80619,-53.367 -63.58636,-53.367 -64.36653,-53.367 -65.1467,-54.8377 -65.1467,-56.3084 -65.1467,-57.7791 -65.1467,-59.2498 -65.1467,-60.7205 -65.1467,-62.1912 -65.1467,-63.6619 -65.1467,-65.1326 -65.1467,-66.6033 -65.1467,-68.074 -65.1467,-68.074 -64.36653,-68.074 -63.58636,-68.074 -62.80619,-68.074 -62.02602,-68.074 -61.24585,-68.074 -60.46568,-68.074 -59.68551,-68.074 -58.90534,-68.074 -58.12517,-68.074 -57.345))", "dataset_titles": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "datasets": [{"dataset_uid": "601519", "doi": "10.15784/601519", "keywords": "Antarctica; Antarctic Peninsula; Chemical Composition; Chemistry:rock; Chemistry:Rock; Geochemistry; Isotope Data; Trace Elements", "people": "Saal, Alberto", "repository": "USAP-DC", "science_program": null, "title": "Major, trace elements contents and radiogenic isotopes of erupted lavas Antarctic Peninsula and Phoenix Ridge", "url": "https://www.usap-dc.org/view/dataset/601519"}], "date_created": "Tue, 22 Jun 2021 00:00:00 GMT", "description": "The Earth\u0027s mantle influences the movement of tectonic plates and volcanism on the surface. One way to understand the composition and nature of the Earth\u0027s mantle is by studying the chemistry of basalts, which originate by volcanic eruptions of partially melting mantle rocks. This study will establish the budget and distribution of volatile elements (hydrogen, carbon, fluorine, chlorine, sulfur) in volcanic basalts to better understand the composition of the Earth\u0027s interior. Volatiles influence mantle melting, magma crystallization, magma migration and volcanic eruptions. Their abundances and spatial distribution provide important constraints on models of mantle flow and temperature. Moreover, volatiles are key constituents of the Earth\u0027s atmosphere and oceans. Establishing the cycles of volatiles between the Earth\u0027s interior and surface is of fundamental importance to understand the long-term evolution of our planet. This project supports a graduate student and research scientist at Brown University. It promotes the collaboration with geochemists from eleven institutions representing six different countries: USA, Germany, United Kingdom, Argentina, South Korea and Japan, and utilizes several NSF-funded USA analytical facilities. Communication of results will occur through: 1) peer-reviewed journals, presentations at conferences and invited university lectures, 2) hands-on science learning activities for local elementary and high school classes, and 3) outreach to the general audience through public lectures. Over the last 60 years of funded research, the Antarctic Peninsula and nearby ocean ridges have been extensively investigated providing information on the origin of the magmatism, and the composition, structure, temperature and evolution of the lithospheric and asthenospheric mantle. Diverse hypotheses have been proposed for the origin of the magmatism in the Antarctic Peninsula, from flux melting of the mantle wedge during devolatilization of the subducted Phoenix plate, to adiabatic decompression melting of a carbonated and hydrous asthenosphere, to melting of a volatile-rich metasomatized subcontinental lithospheric mantle. All proposed hypotheses invoke the role of volatiles. Surprisingly, data on the volatile contents of basalts and mantle from this region are non-existent. This is a significant omission from the geochemical data set, given the important role volatile elements play in the generation and composition of magmas and their sources. The focus of our research is to examine the regional variations in volatile contents (C, H, F, S, Cl) in geochemically well-characterized Pliocene-recent basalts from the Antarctic Peninsula and Phoenix ridge. Our goal is to establish the budget and distribution of volatiles in the mantle to understand 1) the processes responsible for the generation of chemically diverse basalts in close spatial and temporal proximity and 2) the nature (lithology, composition and temperature) of the heterogeneous mantle source beneath the Antarctic Peninsula and Phoenix ridge.", "east": -53.367, "geometry": "POINT(-60.7205 -61.24585)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; USA/NSF; USAP-DC; TRACE ELEMENTS; MAJOR ELEMENTS; Amd/Us; LABORATORY; ROCKS/MINERALS/CRYSTALS; Magmatic Volatiles; AMD", "locations": "Antarctic Peninsula", "north": -57.345, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Saal, Alberto", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -65.1467, "title": "Magmatic Volatiles, Unraveling the Reservoirs and Processes of the Volcanism in the Antarctic Peninsula", "uid": "p0010196", "west": -68.074}, {"awards": "1141411 Baker, Ian", "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": "Laboratory Experiments with H2SO4-Doped Ice; The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "datasets": [{"dataset_uid": "601081", "doi": "10.15784/601081", "keywords": null, "people": "Hammonds, Kevin", "repository": "USAP-DC", "science_program": null, "title": "Laboratory Experiments with H2SO4-Doped Ice", "url": "https://www.usap-dc.org/view/dataset/601081"}, {"dataset_uid": "600380", "doi": "10.15784/600380", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice; Physical Properties; Snow", "people": "Baker, Ian", "repository": "USAP-DC", "science_program": null, "title": "The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "url": "https://www.usap-dc.org/view/dataset/600380"}], "date_created": "Fri, 09 Oct 2020 00:00:00 GMT", "description": "Baker/1141411 This award supports a project to undertake a systematic examination of the effects of soluble impurities, particularly sulfuric acid, on the creep of polycrystalline ice as function of temperature, strain rate and impurity concentration. The working hypothesis is that soluble impurities will increase the flow rate of polycrystalline ice compared to high-purity ice, that this effect will be temperature dependent and that the impurities by affecting the re-crystallization and grain growth will change the fabric of the ice. Both H2SO4-doped and high-purity poly-crystalline ice will be produced by freezing sheets of ice, breaking them up, sieving the ice particles and then sintering them in a mold into fine-grained cylindrical specimens with at least ten grains across their diameter. The resulting microstructures (dislocation structure, grain size and shape, grain boundary character and micro-structural location of the acid) will be characterized using a variety of techniques including: optical microscopy, scanning electron microscopy, including secondary electron imaging, electron backscattered patterns, energy dispersive X-ray spectroscopy, electron channeling contrast imaging, and X-ray topography. The creep of both the H2SO4-doped and the high-purity polycrystalline ice will be undertaken at a range of temperatures and stresses. The ice?s response to the creep deformation (grain boundary sliding, dislocation motion, re-crystallization, grain boundary migration, impurity redistribution) will be studied using a combination of methods. The creep behavior will be modeled and related to the microstructure. Of particular interest is how impurities affect the activation energy for creep. The intellectual merit of the work is that it will lead to a better understanding of glacier ice and will enable glaciologists to model the influence of impurities on the flow and fabric development in polycrystalline ice. The broader impacts of the project include the knowledge that will be gained of the effects of impurities on the flow of ice which will allow paleoclimatologists to better interpret ice core data and will allow scientists developing predictive models to better address the flow of ice sheets under various climate change scenarios. The project will also lead to the education and training of a Ph.D. student, several undergraduates and some high school students. Results from the research will be published in refereed journals. Several undergraduates, typically two per year, will also perform the work. Dartmouth aggressively courts minority students at all degree levels, and we will seek women or minority group undergraduates for this project. The undergraduates will be supported by Dartmouth?s nationally-honored Women In Science Project or by REU funding. The undergraduates? research will integrate closely with the Ph.D. student?s studies. Hanover High School students will also be involved in the project and develop an educational kit to introduce students to the properties of ice. Results from the research will be published in refereed journals and presented at conferences.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; USAP-DC; SNOW/ICE; Amd/Us; LABORATORY; Antarctica; AMD", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "The Effects of Soluble Impurities on the Flow and Fabric of Polycrystalline Ice", "uid": "p0010133", "west": -180.0}, {"awards": "1543450 Countway, Peter", "bounds_geometry": "POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63))", "dataset_titles": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ; Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Western Antarctic Peninsula plankton raw sequence reads", "datasets": [{"dataset_uid": "601644", "doi": "10.15784/601644", "keywords": "3H-Leu; Antarctica; Bacteria; Biota; DMSP; Heterotrophic Bacterial Production; Palmer Station", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601644"}, {"dataset_uid": "200337", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Western Antarctic Peninsula plankton raw sequence reads", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA870587?reviewer=bmud2tbbrqbus79i2n2hb83uio"}, {"dataset_uid": "601645", "doi": "10.15784/601645", "keywords": "Antarctica; Nitrate; Nitrite; Palmer Station; Phosphate", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ", "url": "https://www.usap-dc.org/view/dataset/601645"}, {"dataset_uid": "601648", "doi": "10.15784/601648", "keywords": "Antarctica; Biota; Dimethyl Sulfide; Dimethylsulfoniopropionate; Dimethylsulfoxide; DMSP; DMSP Lyase; Palmer Station", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601648"}, {"dataset_uid": "601646", "doi": "10.15784/601646", "keywords": "Antarctica; Carbon; Dissolved Organic Carbon; Nitrogen; Palmer Station; TDN; Total Dissolved Nitrogen", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601646"}, {"dataset_uid": "601647", "doi": "10.15784/601647", "keywords": "Antarctica; Palmer Station; Phytoplankton", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601647"}], "date_created": "Sat, 01 Aug 2020 00:00:00 GMT", "description": "The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\\DMS production. The proposal aims to examine the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project will leverage the Antarctic research to introduce concepts and data linking microbial diversity and biogeochemistry to a range of audiences (including high school and undergraduate students in Maine). The project will also engage teacher and students in rural K-8 schools and will allow a collaboration with a science writer and illustrator who will join the team in the field. The writer will use the southern ocean experience as the setting for a poster and a book about the proposed research and the scientists studying extreme environments. The project will examine (1) the extent to which the cycling of DMSP in southern ocean waters influences the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influence the magnitude and rates of DMSP cycling; (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to additions of DMSP; and, to synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work will be accomplished by conducting continuous growth experiments with DMSP-amended natural samples during field sampling of different microbial communities present in summer and fall. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis.", "east": -63.0, "geometry": "POINT(-64.5 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; COMMUNITY DYNAMICS; FIELD INVESTIGATION; AMD; PLANKTON; Amd/Us; BIOGEOCHEMICAL CYCLES; Palmer Station; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Countway, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "GenBank; USAP-DC", "science_programs": null, "south": -66.0, "title": "Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean", "uid": "p0010120", "west": -66.0}, {"awards": "1543347 Rosenheim, Brad; 1543396 Christner, Brent; 1543405 Leventer, Amy; 1543453 Lyons, W. Berry; 1543537 Priscu, John; 1543441 Fricker, Helen", "bounds_geometry": "POLYGON((-163.611 -84.33543,-162.200034 -84.33543,-160.789068 -84.33543,-159.378102 -84.33543,-157.967136 -84.33543,-156.55617 -84.33543,-155.145204 -84.33543,-153.734238 -84.33543,-152.323272 -84.33543,-150.912306 -84.33543,-149.50134 -84.33543,-149.50134 -84.3659157,-149.50134 -84.3964014,-149.50134 -84.4268871,-149.50134 -84.4573728,-149.50134 -84.4878585,-149.50134 -84.5183442,-149.50134 -84.5488299,-149.50134 -84.5793156,-149.50134 -84.6098013,-149.50134 -84.640287,-150.912306 -84.640287,-152.323272 -84.640287,-153.734238 -84.640287,-155.145204 -84.640287,-156.55617 -84.640287,-157.967136 -84.640287,-159.378102 -84.640287,-160.789068 -84.640287,-162.200034 -84.640287,-163.611 -84.640287,-163.611 -84.6098013,-163.611 -84.5793156,-163.611 -84.5488299,-163.611 -84.5183442,-163.611 -84.4878585,-163.611 -84.4573728,-163.611 -84.4268871,-163.611 -84.3964014,-163.611 -84.3659157,-163.611 -84.33543))", "dataset_titles": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset; Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset; Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland; CTD data from Mercer Subglacial Lake and access borehole; Discrete bulk sediment properties data from Mercer Subglacial Lake; Isotopic data from Whillans Ice Stream grounding zone, West Antarctica; Mercer Subglacial Lake radiocarbon and stable isotope data ; Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995); Mercer Subglacial Lake (SLM) noble gas and isotopic data; Mercer Subglacial Lake water column viral metagenomic sequencing; Salsa sediment cores; Sediment porewater properties data from Mercer Subglacial Lake; Water column biogeochemical data from Mercer Subglacial Lake", "datasets": [{"dataset_uid": "200342", "doi": null, "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Mercer Subglacial Lake water column viral metagenomic sequencing", "url": "https://www.ncbi.nlm.nih.gov/biosample/32811410"}, {"dataset_uid": "200214", "doi": "10.7283/YW8Z-TK03", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA02-WIS_LAKES_02 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/YW8Z-TK03"}, {"dataset_uid": "200246", "doi": "", "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "Salsa sediment cores", "url": "https://osu-mgr.org"}, {"dataset_uid": "200215", "doi": "10.7283/C503-KS23", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA06-WIS_LAKES_06 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/C503-KS23"}, {"dataset_uid": "601663", "doi": "10.15784/601663", "keywords": "Antarctica; Carbon; Cell Counts; Geochemistry; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "people": "Priscu, John; Dore, John; Skidmore, Mark; Hawkings, Jon; Steigmeyer, August; Li, Wei; Barker, Joel; Tranter, Martyn; Science Team, SALSA", "repository": "USAP-DC", "science_program": null, "title": "Water column biogeochemical data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601663"}, {"dataset_uid": "200216", "doi": "10.7283/F8NH-CV04", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA07-WIS_LAKES_07 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F8NH-CV04"}, {"dataset_uid": "601672", "doi": "10.15784/601672", "keywords": "Antarctica; Isotope; Mercer Subglacial Lake; Radiocarbon; Subglacial Lake", "people": "Rosenheim, Brad; Venturelli, Ryan", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake radiocarbon and stable isotope data ", "url": "https://www.usap-dc.org/view/dataset/601672"}, {"dataset_uid": "200213", "doi": "10.7283/F7BB-JH05", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ13-WIS_GroundingZone_13 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/F7BB-JH05"}, {"dataset_uid": "200282", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Mercer Subglacial Lake (SLM) microbial composition: 16S rRNA genes (Sequence Read Archive; BioProject: PRJNA790995)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA790995"}, {"dataset_uid": "601661", "doi": "10.15784/601661", "keywords": "Antarctica; Carbon; Glacier; Glaciers/ice Sheet; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; Physical Properties; SALSA; Sediment Core; Sulfur; West Antarctic Ice Sheet", "people": "Campbell, Timothy; Michaud, Alexander; Hawkings, Jon; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Dore, John; Science Team, SALSA", "repository": "USAP-DC", "science_program": null, "title": "Discrete bulk sediment properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601661"}, {"dataset_uid": "200212", "doi": "10.7283/PT0Q-JB95", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - GZ01-WIS_GroundingZone_01 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/PT0Q-JB95"}, {"dataset_uid": "601360", "doi": "10.15784/601360", "keywords": "Antarctica; Radiocarbon; Sediment; Whillans Ice Stream", "people": "Venturelli, Ryan A", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Isotopic data from Whillans Ice Stream grounding zone, West Antarctica", "url": "https://www.usap-dc.org/view/dataset/601360"}, {"dataset_uid": "601472", "doi": "10.15784/601472", "keywords": "Antarctica; Bistatic Radar; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPS Data; Greenland; Lake Whillans; Radar; Store Glacier; Whillans Ice Stream; WISSARD", "people": "Schroeder, Dustin; Siegfried, Matthew; Peters, Sean; MacKie, Emma; Dawson, Eliza; Christoffersen, Poul; Bienert, Nicole", "repository": "USAP-DC", "science_program": "WISSARD", "title": "Bistatic Radar Sounding of Whillans Ice Stream, Antarctica and Store Glacier, Greenland", "url": "https://www.usap-dc.org/view/dataset/601472"}, {"dataset_uid": "601498", "doi": "10.15784/601498", "keywords": "Antarctica; Mercer Subglacial Lake; Noble Gas", "people": "Lyons, W. Berry; Gardner, Christopher B.", "repository": "USAP-DC", "science_program": null, "title": "Mercer Subglacial Lake (SLM) noble gas and isotopic data", "url": "https://www.usap-dc.org/view/dataset/601498"}, {"dataset_uid": "601657", "doi": "10.15784/601657", "keywords": "Antarctica; Conductivity; CTD; Depth; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Hot Water Drill; Mercer Subglacial Lake; Physical Properties; SALSA; Subglacial Lake; Temperature", "people": "Leventer, Amy; Dore, John; Priscu, John; Rosenheim, Brad", "repository": "USAP-DC", "science_program": null, "title": "CTD data from Mercer Subglacial Lake and access borehole", "url": "https://www.usap-dc.org/view/dataset/601657"}, {"dataset_uid": "200217", "doi": "10.7283/3JMY-Y504", "keywords": null, "people": null, "repository": "UNAVCO", "science_program": null, "title": "Antarctica - PI Continuous - LA09-WIS_LAKES_09 P.S. - GPS/GNSS Observations Dataset", "url": "https://www.unavco.org/data/doi/10.7283/3JMY-Y504"}, {"dataset_uid": "601664", "doi": "10.15784/601664", "keywords": "Antarctica; Gas; Geochemistry; Glacier; Glaciology; Mercer Subglacial Lake; Methane; SALSA; Sediment Core; West Antarctic Ice Sheet", "people": "Skidmore, Mark; Science Team, SALSA; Steigmeyer, August; Tranter, Martyn; Michaud, Alexander; Dore, John", "repository": "USAP-DC", "science_program": null, "title": "Sediment porewater properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601664"}], "date_created": "Thu, 16 Jul 2020 00:00:00 GMT", "description": "The Antarctic subglacial environment remains one of the least explored regions on Earth. This project will examine the physical and biological characteristics of Subglacial Lake Mercer, a lake that lies 1200m beneath the West Antarctic Ice Sheet. This study will address key questions relating to the stability of the ice sheet, the subglacial hydrological system, and the deep-cold subglacial biosphere. The education and outreach component aims to widely disseminate results to the scientific community and to the general public through short films, a blog, and a website. Subglacial Lake Mercer is one of the larger hydrologically active lakes in the southern basin of the Whillans Ice Plain, West Antarctica. It receives about 25 percent of its water from East Antarctica with the remainder originating from West Antarctica, is influenced by drain/fill cycles in a lake immediately upstream (Subglacial Lake Conway), and lies about 100 km upstream of the present grounding line of the Ross Ice Shelf. This site will yield information on the history of the Whillans and Mercer Ice Streams, and on grounding line migration. The integrated study will include direct sampling of basal ice, water, and sediment from the lake in concert with surface geophysical surveys over a three-year period to define the hydrological connectivity among lakes on the Whillans Ice Plain and their flow paths to the sea. The geophysical surveys will furnish information on subglacial hydrology, aid the site selection for hot-water drilling, and provide spatial context for interpreting findings. The hot-water-drilled boreholes will be used to collect basal ice samples, provide access for direct measurement of subglacial physical, chemical, and biological conditions in the water column and sediments, and to explore the subglacial water cavities using a remotely operated vehicle equipped with sensors, cameras, and sampling equipment. Data collected from this study will address the overarching hypothesis \"Contemporary biodiversity and carbon cycling in hydrologically-active subglacial environments associated with the Mercer and Whillans ice streams are regulated by the mineralization and cycling of relict marine organic matter and through interactions among ice, rock, water, and sediments\". The project will be undertaken by a collaborative team of scientists, with expertise in microbiology, biogeochemistry, hydrology, geophysics, glaciology, marine geology, paleoceanography, and science communication.", "east": -149.50134, "geometry": "POINT(-156.55617 -84.4878585)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENTS; Antarctica; ISOTOPES; Subglacial Lake; USAP-DC; VIRUSES; PALEOCLIMATE RECONSTRUCTIONS; BACTERIA/ARCHAEA; LABORATORY; Radiocarbon; Whillans Ice Stream; AMD; SALSA; ECOSYSTEM FUNCTIONS; RADIOCARBON; FIELD INVESTIGATION; ICE MOTION; Mercer Ice Stream; Amd/Us; USA/NSF; GLACIERS/ICE SHEETS", "locations": "Antarctica; Mercer Ice Stream; Whillans Ice Stream", "north": -84.33543, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Instrumentation and Support; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Integrated System Science", "paleo_time": null, "persons": "Rosenheim, Brad; Fricker, Helen; Priscu, John; Leventer, Amy; Dore, John; Lyons, W. Berry; Christner, Brent", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "GenBank", "repositories": "GenBank; NCBI GenBank; OSU-MGR; UNAVCO; USAP-DC", "science_programs": null, "south": -84.640287, "title": "Collaborative Research: Subglacial Antarctic Lakes Scientific Access (SALSA): Integrated Study of Carbon Cycling in Hydrologically-active Subglacial Environments", "uid": "p0010119", "west": -163.611}, {"awards": "1551195 Burdige, David", "bounds_geometry": "POLYGON((-71 -64,-70.1 -64,-69.2 -64,-68.3 -64,-67.4 -64,-66.5 -64,-65.6 -64,-64.7 -64,-63.8 -64,-62.9 -64,-62 -64,-62 -64.4,-62 -64.8,-62 -65.2,-62 -65.6,-62 -66,-62 -66.4,-62 -66.8,-62 -67.2,-62 -67.6,-62 -68,-62.9 -68,-63.8 -68,-64.7 -68,-65.6 -68,-66.5 -68,-67.4 -68,-68.3 -68,-69.2 -68,-70.1 -68,-71 -68,-71 -67.6,-71 -67.2,-71 -66.8,-71 -66.4,-71 -66,-71 -65.6,-71 -65.2,-71 -64.8,-71 -64.4,-71 -64))", "dataset_titles": "Expedition data of NBP1601; Project: Organic Carbon Oxidation and Iron Remobilization by West Antarctic Shelf Sediments", "datasets": [{"dataset_uid": "200148", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Project: Organic Carbon Oxidation and Iron Remobilization by West Antarctic Shelf Sediments", "url": "https://www.bco-dmo.org/project/806864"}, {"dataset_uid": "002665", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP1601", "url": "https://www.rvdata.us/search/cruise/NBP1601"}], "date_created": "Tue, 16 Jun 2020 00:00:00 GMT", "description": "General Statement: The continental shelf region west of the Antarctic Peninsula has recently undergone dramatic changes and ecosystem shifts, and the community of organisms that live in, or feed off, the sea floor sediments is being impacted by species invasions from the north. Previous studies of these sediments indicate that this community may consume much more of the regional productivity than previously estimated, suggesting that sediments are a rich and important component of this ecosystem and one that may be ripe for dramatic change. Furthermore, under richer sediment conditions, iron is mobilized and released back to the water column. Since productivity in this ecosystem is thought to be limited by the availability of iron, increased rates of iron release from these sediments could stimulate productivity and promote greater overall ecosystem change. In this research, a variety of sites across the shelf region will be sampled to accurately evaluate the role of sediments in consuming ecosystem productivity and to estimate the current level of iron release from the sediments. This project will provide a baseline set of sediment results that will present a more complete picture of the west Antarctic shelf ecosystem, will allow for comparison with water column measurements and for evaluation of the fundamental workings of this important ecosystem. This is particularly important since high latitude systems may be vulnerable to the effects of climate fluctuations. Both graduate and undergraduate students will be trained. Presentations will be made at scientific meetings, at other universities, and at outreach events. A project web site will present key results to the public and explain how this new information improves understanding of Antarctic ecosystems. Technical Description of Project: In order to determine the role of sediments within the west Antarctic shelf ecosystem, this project will determine the rates of sediment organic matter oxidation at a variety of sites across the Palmer Long Term Ecosystem Research (LTER) study region. To estimate the rates of release of iron and manganese from the sediments, these same sites will be sampled for detailed vertical distributions of the concentrations of these metals both in the porewaters and in important mineral phases. Since sediment sampling will be done at LTER sites, the sediment data can be correlated with the rich productivity data set from the LTER. In detail, the project: a) will determine the rates of oxygen consumption, organic carbon oxidation, nutrient release, and iron mobilization by shelf sediments west of the Antarctic Peninsula; b) will investigate the vertical distribution of diagenetic reactions within the sediments; and c) will assess the regional importance of these sediment rates. Sediment cores will be used to determine sediment-water fluxes of dissolved oxygen, total carbon dioxide, nutrients, and the vertical distributions of these dissolved compounds, as well as iron and manganese in the pore waters. Bulk sediment properties of porosity, organic carbon and nitrogen content, carbonate content, biogenic silica content, and multiple species of solid-phase iron, manganese, and sulfur species will also be determined. These measurements will allow determination of total organic carbon oxidation and denitrification rates, and the proportion of aerobic versus anaerobic respiration at each site. Sediment diagenetic modeling will link the processes of organic matter oxidation to metal mobilization. Pore water and solid phase iron and manganese distributions will be used to model iron diagenesis in these sediments and to estimate the iron flux from the sediments to the overlying waters. Finally, the overall regional average and distribution of the sediment processes will be compared with the distributions of seasonally averaged chlorophyll biomass and productivity.", "east": -62.0, "geometry": "POINT(-66.5 -66)", "instruments": null, "is_usap_dc": true, "keywords": "BIOGEOCHEMICAL CYCLES; Iron Remobilization; R/V NBP; NBP1601; SEDIMENT CHEMISTRY; USAP-DC; West Antarctic Shelf", "locations": "West Antarctic Shelf", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Burdige, David; Christensen, John", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "BCO-DMO", "repositories": "BCO-DMO; R2R", "science_programs": null, "south": -68.0, "title": "Organic carbon oxidation and iron remobilization by West Antarctic shelf sediments ", "uid": "p0010108", "west": -71.0}, {"awards": "1341717 Ackley, Stephen; 1341606 Stammerjohn, Sharon; 1341513 Maksym, Edward; 1543483 Sedwick, Peter; 1341725 Guest, Peter", "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 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": "601609", "doi": "10.15784/601609", "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; 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": "601422", "doi": "10.15784/601422", "keywords": "Antarctica; 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"}, {"dataset_uid": "601183", "doi": "10.15784/601183", "keywords": "Antarctica; Glaciology; Ice Concentration; Ice Thickness; Ice Type; NBP1704; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Sea Ice; Snow Depth; Snow/ice; 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": "601184", "doi": "10.15784/601184 ", "keywords": "Air Temperature; Antarctica; Atmosphere; 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": "601185", "doi": "10.15784/601185 ", "keywords": "Air Temperature; Antarctica; Atmosphere; Atmospheric Surface Winds; 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": "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": "601188", "doi": "10.15784/601188", "keywords": "Aerogeophysics; Airborne Laser Altimetry; Antarctica; LIDAR; PIPERS; Ross Sea; Sea Ice", "people": "Bertinato, Christopher; Locke, Caitlin; Bell, Robin; Xie, Hongjie; Dhakal, Tejendra", "repository": "USAP-DC", "science_program": null, "title": "PIPERS Airborne LiDAR Data", "url": "https://www.usap-dc.org/view/dataset/601188"}, {"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": "601191", "doi": "10.15784/601191", "keywords": "Air Temperature; Antarctica; Atmosphere; 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": "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": "601207", "doi": "10.15784/601207", "keywords": "Antarctica; Digital Elevation Model; 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; Jeffrey Mei, M.; Mei, M. Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "Sea Ice Layer Cakes, PIPERS 2017", "url": "https://www.usap-dc.org/view/dataset/601207"}], "date_created": "Mon, 10 Jun 2019 00:00:00 GMT", "description": "Proposal Title: Collaborative Research: Seasonal Sea Ice Production in the Ross Sea, Antarctica (working title changed from submitted title) Institutions: UT-San Antonio; Columbia University; Naval Postgraduate School; Woods Hole Oceanographic Institute; UC@Boulder 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. The 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; METHANE; POLYNYAS; CONDUCTIVITY; SEA ICE; Ross Sea; WATER MASSES; TURBULENCE; USAP-DC; Amd/Us", "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; Nuss, Wendell; Maksym, Edward; Stammerjohn, Sharon; Cassano, John; Guest, Peter; Sedwick, Peter; Xie, Hongjie", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "BCO-DMO; 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": "0944659 Kiene, Ronald; 0944686 Kieber, David", "bounds_geometry": "POLYGON((-180 -68,-177 -68,-174 -68,-171 -68,-168 -68,-165 -68,-162 -68,-159 -68,-156 -68,-153 -68,-150 -68,-150 -69,-150 -70,-150 -71,-150 -72,-150 -73,-150 -74,-150 -75,-150 -76,-150 -77,-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 -77,160 -76,160 -75,160 -74,160 -73,160 -72,160 -71,160 -70,160 -69,160 -68,162 -68,164 -68,166 -68,168 -68,170 -68,172 -68,174 -68,176 -68,178 -68,-180 -68))", "dataset_titles": "Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "datasets": [{"dataset_uid": "600150", "doi": "10.15784/600150", "keywords": "Antarctica; Biota; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Oceans; Ross Sea", "people": "Kiene, Ronald", "repository": "USAP-DC", "science_program": null, "title": "Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "url": "https://www.usap-dc.org/view/dataset/600150"}, {"dataset_uid": "600117", "doi": "10.15784/600117", "keywords": "Biota; Ross Sea; Southern Ocean", "people": "Kieber, David John", "repository": "USAP-DC", "science_program": null, "title": "Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "url": "https://www.usap-dc.org/view/dataset/600117"}], "date_created": "Wed, 16 Dec 2015 00:00:00 GMT", "description": "Spectacular blooms of Phaeocystis antarctica in the Ross Sea, Antarctica are the source of some of the world\u0027s highest concentrations of dimethylsulfoniopropionate (DMSP) and its volatile degradation product, dimethylsulfide (DMS). The flux of DMS from the oceans to the atmosphere in this region and its subsequent gas phase oxidation generates aerosols that have a strong influence on cloud properties and possibly climate. In the oceans, DMS and DMSP are quantitatively significant components of the carbon, sulfur, and energy flows in marine food webs, especially in the Ross Sea. Despite its central role in carbon and sulfur biogeochemistry in the Ross Sea, surprisingly little is known about the physiological functions of DMSP in P. Antarctica. The research will isolate and characterize DMSP lyases from P. antarctica, with the goal of obtaining amino acid and gene sequence information on these important enzymes. The physiological studies will focus on the effects of varying intensities of photosynthetically active radiation, with and without ultraviolet radiation as these are factors that we have found to be important controls on DMSP and DMS dynamics. The research also will examine the effects of prolonged darkness on the dynamics of DMSP and related compounds in P. antarctica, as survival of this species during the dark Antarctic winter and at sub-euphotic depths appears to be an important part of the Phaeocystis? ecology. A unique aspect of this work is the focus on measurements of intracellular MSA, which if detected, would provide strong evidence for in vivo radical scavenging functions for methyl sulfur compounds. The study will advance understanding of what controls DMSP cycling and ultimately DMS emissions from the Ross Sea and also provide information on what makes P. antarctica so successful in this extreme environment. The research will directly benefit and build on several interrelated ocean-atmosphere programs including the International Surface Ocean Lower Atmosphere Study (SOLAS) program. The PIs will participate in several activities involving K-12 education, High School teacher training, public education and podcasting through the auspices of the Dauphin Island Sea Lab Discovery Hall program and SUNY ESF. Two graduate students will be employed full time, and six undergraduates (2 each summer) will be trained as part of this project.", "east": -150.0, "geometry": "POINT(-175 -73)", "instruments": null, "is_usap_dc": true, "keywords": "Amd/Us; Not provided; Ecophysiology; AMD; USAP-DC; FIELD SURVEYS", "locations": null, "north": -68.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald; Kieber, David John", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Collaborative Research: Ecophysiology of DMSP and related compounds and their contributions to carbon and sulfur dynamics in Phaeocystis antarctica", "uid": "p0000085", "west": 160.0}, {"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": "609659", "doi": "10.7265/N5CV4FPK", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; 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"}, {"dataset_uid": "601361", "doi": "10.15784/601361", "keywords": "Antarctica; Carbonyl Sulfide; Trace Gases", "people": "Saltzman, Eric; Aydin, Murat", "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"}], "date_created": "Tue, 27 Oct 2015 00:00:00 GMT", "description": "Aydin/1043780 This 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 Earth Sciences; Antarctic Glaciology", "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": "0939628 Barletta, Robert", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 06 Aug 2015 00:00:00 GMT", "description": "Biogenic sulfur compounds, such as dimethyl sulfide (DMS), its precursors dimethyl sulfoniopropionate (DMSP) and dimethyl sulfoxide (DMSO), and its atmospheric oxidation product, methane sulfonic acid (MSA), are important components of the global sulfur cycle that significantly impact global climate. The roles of DMSP and DMSO within the organisms that produce them, as well as their intracellular concentrations, are poorly understood. DMSO has been speculated to play a role in intracellular osmoregulation, cryoprotection and scavenging of reactive oxygen species, but its intracellular concentration in plankton has only been inferred. Quantitative measurement of the concentration of biogenic sulfur compounds in vivo is necessary to more completely understand their biogeochemistry. The principal investigator has developed methods for the quantitative analysis of biogenic sulfur compounds using Raman spectroscopy, which have resulted in the detection of DMSO with a sensitivity of \u003c10 mM - far lower than the current estimates of its intracellular concentrations. The research will extend this technique to DMSP. The direct determination of the intracellular DMSP and DMSO, will allow the proposed roles of these compounds in phytoplankton to be investigated. Lastly, using field-collected cores, measurements will be made of the intracellular sulfur compounds as well as the concentration of molecular anions in the sea ice micro-environment. As an RUI project, successful completion of this work will have a substantial impact on undergraduate education in the Chemistry Department at the University of South Alabama, exposing undergraduates and, particularly, under-represented minorities in the sciences to cutting-edge research. It will provide financial support for their education and allow them to present research in journal articles and at technical meetings. Contacts with scientists in the field of Antarctic research at other institutions will give students the opportunity to interact with researchers in related fields, broadening their experience base.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Barletta, Robert", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -90.0, "title": "RUI: Analysis of Intracellular Biogenic Sulfur Using micro-Raman Spectroscopy", "uid": "p0000403", "west": -180.0}, {"awards": "0739684 Hatcher, Patrick", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 26 Sep 2012 00:00:00 GMT", "description": "This award supports a project to fully develop the analytical protocols needed to exploit a relatively new technique for the analysis of soluble organic matter in ice core samples. The technique couples Electrospray ionization to high resolution Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS). Sample volume will be reduced and pre-concentration steps will be eliminated. Following method optimization a suite of ice core samples will be studied from several Antarctic and Greenland locations to address several hypothesis driven research questions. Preliminary results show that a vast record of relatively high molecular weight organic material exists in ice core samples and intriguing results from a few samples warrant further investigation. Several important questions related to developing a better understanding of the nature and paleo record of organic matter in ice cores will be addressed. These include developing a better understanding of the origin of nitrogen and sulfur isotopes in pre-industrial vs. modern samples, developing the methods to apply molecular biomarker techniques, routinely used by organic geochemists for sediment analyses, to the analysis of organic matter in ice cores, tracking the level of oxidation of homologous series of compounds and using them as a proxy for atmospheric oxidant levels in the past and determining whether or not high resolution FTICR mass spectral analysis can provide the ice core community with a robust method to analyze organic materials at the molecular level. The intellectual merit of this work is that this analytical method will provide a new understanding of the nature of organic matter in ice, possibly leading to the discovery of multitudes of molecular species indicative of global change processes whose abundances can be compared with other change proxies. The proposed studies are of an exploratory nature and potentially transformative for the field of ice core research and cryobiology. The broader impacts of these studies are that they should provide compelling evidence regarding organic matter sources, atmospheric processing and anthropogenic inputs to polar ice and how these have varied over time. The collaborative work proposed here will partner atmospheric chemistry/polar ice chemistry expertise with organic geochemistry expertise, resulting in significant contributions to both fields of study and significant advances in ice core analysis. Training of both graduate and undergraduate students will be a key component of the project and students will be involved in collaborative research using advanced analytical instrumentation, presentation of research results at national meetings, and will participate in manuscript preparation.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": false, "keywords": "Ice Core; Isotope; Organic Matter; Nitrogen; Sulfur; Not provided; LABORATORY; Mass Spectrometry; COMPUTERS; Molecular", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Hatcher, Patrick; Grannas, Amanda", "platforms": "Not provided; OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Molecular Level Characterization of Organic Matter in Ice Cores using High-resolution FTICR mass spectrometry", "uid": "p0000707", "west": null}, {"awards": "0230499 Kieber, David", "bounds_geometry": "POLYGON((-179.99998 -43.58056,-143.999984 -43.58056,-107.999988 -43.58056,-71.999992 -43.58056,-35.999996 -43.58056,0 -43.58056,35.999996 -43.58056,71.999992 -43.58056,107.999988 -43.58056,143.999984 -43.58056,179.99998 -43.58056,179.99998 -46.971468,179.99998 -50.362376,179.99998 -53.753284,179.99998 -57.144192,179.99998 -60.5351,179.99998 -63.926008,179.99998 -67.316916,179.99998 -70.707824,179.99998 -74.098732,179.99998 -77.48964,143.999984 -77.48964,107.999988 -77.48964,71.999992 -77.48964,35.999996 -77.48964,0 -77.48964,-35.999996 -77.48964,-71.999992 -77.48964,-107.999988 -77.48964,-143.999984 -77.48964,-179.99998 -77.48964,-179.99998 -74.098732,-179.99998 -70.707824,-179.99998 -67.316916,-179.99998 -63.926008,-179.99998 -60.5351,-179.99998 -57.144192,-179.99998 -53.753284,-179.99998 -50.362376,-179.99998 -46.971468,-179.99998 -43.58056))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "001616", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0409"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world\u0027s highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. \u003cbr/\u003e\u003cbr/\u003eThis project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. \u003cbr/\u003e\u003cbr/\u003eBoth Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.", "east": 179.99998, "geometry": "POINT(0 -89.999)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -43.58056, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -77.48964, "title": "Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica", "uid": "p0000582", "west": -179.99998}, {"awards": "0230497 Kiene, Ronald", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0409", "datasets": [{"dataset_uid": "002640", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0409", "url": "https://www.rvdata.us/search/cruise/NBP0409"}, {"dataset_uid": "001616", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0409"}], "date_created": "Tue, 17 Jan 2012 00:00:00 GMT", "description": "Areas of the Southern Ocean have spectacular blooms of phytoplankton during the austral spring and early summer. One of the dominant phytoplankton species, the haptophyte Phaeocystis antarctica, is a prolific producer of the organic sulfur compound dimethylsulfoniopropionate (DMSP) and Phaeocystis blooms are associated with some of the world\u0027s highest concentrations of DMSP and its volatile degradation product, dimethylsulfide (DMS). Sulfur, in the form of DMS, is transferred from the oceans to the atmosphere and can affect the chemistry of precipitation and influence cloud properties and possibly climate. DMSP and DMS are also quantitatively significant components of the carbon, sulfur and energy flows in many marine food webs, although very little information is available on these processes in high latitude systems. \u003cbr/\u003e\u003cbr/\u003eThis project will study how solar radiation and iron cycling affect DMSP and DMS production by phytoplankton, and the subsequent utilization of these labile forms of organic matter by the microbial food web. Four interrelated hypotheses will be tested in field-based experiments and in situ observations: 1) solar radiation, including enhanced UV-B due to seasonal ozone depletion, plays an important role in determining the net ecosystem production of DMS in the Ross Sea; 2) development of shallow mixed layers promotes the accumulation of DMS in surface waters, because of enhanced exposure of plankton communities to high doses of solar radiation; 3) DMSP production and turnover represent a significant part of the carbon and sulfur flux through polar food webs; 4) bloom development and resulting nutrient depletion (e.g., iron) will result in high production rates of DMSP and high DMS concentrations and atmospheric fluxes. Results from this study will greatly improve understanding of the underlying mechanisms controlling DMSP and DMS concentrations in polar waters, thereby improving our ability to predict DMS fluxes to the atmosphere from this important climatic region. \u003cbr/\u003e\u003cbr/\u003eBoth Drs. Kieber and Kiene actively engage high school, undergraduate and graduate students in their research and are involved in formal programs that target underrepresented groups (NSF-REU and the American Chemical Society-SEED). This project will continue this type of educational outreach. The PIs also teach undergraduate and graduate courses and incorporation of research experiences into their classes will enrich student learning experiences.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Kiene, Ronald", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Collaborative Research: Impact of Solar Radiation and Nutrients on Biogeochemical Cycling of DMSP and DMS in the Ross Sea, Antarctica", "uid": "p0000832", "west": null}, {"awards": "0739598 Aydin, Murat; 0739491 Sowers, Todd", "bounds_geometry": null, "dataset_titles": "Alkanes in Firn Air Samples, Antarctica and Greenland; Methane Isotopes in South Pole Firn Air, 2008", "datasets": [{"dataset_uid": "609504", "doi": "10.7265/N5X9287C", "keywords": "Antarctica; Arctic; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Greenland; Snow/ice; Snow/Ice; South Pole; WAIS Divide", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": null, "title": "Alkanes in Firn Air Samples, Antarctica and Greenland", "url": "https://www.usap-dc.org/view/dataset/609504"}, {"dataset_uid": "609502", "doi": "10.7265/N55T3HFP", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Isotope; Paleoclimate; Snow/ice; Snow/Ice; South Pole", "people": "Sowers, Todd A.", "repository": "USAP-DC", "science_program": null, "title": "Methane Isotopes in South Pole Firn Air, 2008", "url": "https://www.usap-dc.org/view/dataset/609502"}], "date_created": "Thu, 18 Aug 2011 00:00:00 GMT", "description": "This award supports a project to make measurements of methane and other trace gases in firn air collected at South Pole, Antarctica. The analyses will include: methane isotopes (delta-13CH4 and delta-DCH4), light non-methane hydrocarbons (ethane, propane, and n-butane), sulfur gases (COS, CS2), and methyl halides (CH3Cl and CH3Br). The atmospheric burdens of these trace gases reflect changes in atmospheric OH, biomass burning, biogenic activity in terrestrial, oceanic, and wetland ecosystems, and industrial/agricultural activity. The goal of this project is to develop atmospheric histories for these trace gases over the last century through examination of depth profiles of these gases in South Pole firn air. The project will involve two phases: 1) a field campaign at South Pole, Antarctica to drill two firn holes and fill a total of ~200 flasks from depths reaching 120 m, 2) analysis of firn air at University of California, Irvine, Penn State University, and several other collaborating laboratories. Atmospheric histories will be inferred from the measurements using a one dimensional advective/diffusive model of firn air transport. This study will provide new information about the recent changes in atmospheric levels of these gases, providing about a 90 year long time series record that connects the earlier surface and firn air measurements to present day. The project will also explore the possibility of in- situ production of light non-methane hydrocarbons in firn air that is relevant to the interpretation of ice core records. The broader impacts of this research are that it has the potential for significant societal impact by improving our understanding of climate change and man\u0027s input to the atmosphere. The results of this work will be disseminated through the peer review process, and will contribute to environmental assessments, such as the Inter-governmental Panel on Climate Change (IPCC) Climate Assessment and the Word Meteorological Organization (WMO) Stratospheric Ozone Assessment. This research will provide educational opportunities for graduate and undergraduate students, and will contribute to a teacher training program for K-12 teachers in minority school districts.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GC-MS", "is_usap_dc": true, "keywords": "FIELD INVESTIGATION; Isotope; Firn Air Chemistry; Firn Air Isotope Measurements; Not provided; LABORATORY; South Pole; Firn; Delta 13C; Carbon-13; Mass Spectrometer; Deuterium; Mass Spectrometry; Firn Air Samples; Carbon; Gas Chromatography; Polar Firn Air; GROUND-BASED OBSERVATIONS; Methane; Antarctica; Firn Air Isotopes; Delta Deuterium; FIELD SURVEYS; Firn Air; Chromatography; Methane Isotopes; Carbon Isotopes; Stable Isotopes", "locations": "Antarctica; South Pole", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Aydin, Murat; Saltzman, Eric; Sowers, Todd A.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; 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": "Collaborative Research: Methane Isotopes, Hydrocarbons, and other Trace Gases in South Pole Firn Air", "uid": "p0000162", "west": null}, {"awards": "0127037 Neale, Patrick; 0741411 Hutchins, David; 0338097 DiTullio, Giacomo; 0338157 Smith, Walker; 0338350 Dunbar, Robert", "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. Palmer expedition NBP0601", "datasets": [{"dataset_uid": "601340", "doi": null, "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; Fluid Chemistry Data; Geochemistry; NBP0601; Niskin Bottle; Oceans; Ross Sea; R/v Nathaniel B. Palmer; Southern Ocean; Water Measurements", "people": "Smith, Walker; DiTullio, Giacomo", "repository": "USAP-DC", "science_program": null, "title": "Processed Fluid Chemistry Data from the Ross Sea acquired during the Nathaniel B. Palmer expedition NBP0601", "url": "https://www.usap-dc.org/view/dataset/601340"}, {"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": "001687", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0305"}, {"dataset_uid": "001545", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP0608"}, {"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": "600036", "doi": "10.15784/600036", "keywords": "Biota; Chemistry:fluid; 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"}], "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": 177.71042, "geometry": "POINT(175.514375 -57.50998)", "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 PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FRRF", "is_usap_dc": true, "keywords": "B-15J; OCEAN PLATFORMS; FIELD SURVEYS; R/V NBP", "locations": "B-15J", "north": -46.5719, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ditullio, Giacomo; Smith, Walker; Dryer, Jennifer; Neale, Patrick", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; WATER-BASED PLATFORMS \u003e FIXED PLATFORMS \u003e SURFACE \u003e OCEAN PLATFORMS; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -68.44806, "title": "Collaborative Research: Interactive Effects of Iron, Light and Carbon Dioxide on Phytoplankton Community Dynamics in the Ross Sea", "uid": "p0000540", "west": 173.31833}, {"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": "9980379 Baker, Ian", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 15 Feb 2010 00:00:00 GMT", "description": "This award is for support for three years of funding to study the effects of impurities on the flow of poly- crystalline ice. It has been known for thirty years that both hydrofluoric acid (HF) and hydrochloric acid (HCl) dramatically decrease the strength of ice and recent work by the author\u0027s group has shown that sulfuric acid (H2SO4) produces a similar reduction in strength. However, these data are for single crystals at strain rates and stresses that far exceed those found in glaciers and ice sheets, and often at concentrations that far exceed those in natural ice. Therefore, it is not known how impurities found in nature affect the flow of polycrystalline ice at slow strain rates. In this research, the effects of nitric acid and sulfuric acid (which are naturally occurring impurities in ice) on the microstructure (dislocation structure, grain boundary structure and location of the acids) and creep of polycrystalline ice (at a range of temperatures and stresses) will be determined. The ice\u0027s response to creep deformation will be studied using a combination of x-ray topography, optical microscopy and scanning electron microscopy. X-ray microanalysis in an environmental scanning electron microscope will be used to study the location of impurities. The structure and creep behavior of the acid-doped ice will be compared with those of both high-purity laboratory-grown ice and ice from Byrd Station, Antarctica. The end-result of this project will be to elucidate the effects of naturally-occurring acid impurities on the mechanical properties of polycrystalline ice under conditions relevant to the deformation of glaciers and ice sheets, including and understanding of how impurities affect the underlying deformation mechanisms.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PARTICLE DETECTORS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES", "is_usap_dc": true, "keywords": "Ice Core Data; Ice Core; Microstructure; Ice Sheet; Ice Core Chemistry; Antarctic Ice Sheet; LABORATORY", "locations": "Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Baker, Ian; Obbard, Rachel", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": null, "title": "The Effects of Impurities on the Flow of Polycrystalline Ice", "uid": "p0000015", "west": null}, {"awards": "0440478 Tang, Kam", "bounds_geometry": "POINT(166.66267 -77.85067)", "dataset_titles": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "datasets": [{"dataset_uid": "600043", "doi": "10.15784/600043", "keywords": "Biota; McMurdo Sound; Oceans; Phytoplankton; Ross Sea; Southern Ocean; Zooplankton", "people": "Tang, Kam; Smith, Walker", "repository": "USAP-DC", "science_program": null, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial Forms of Phaeocystis Antarctica", "url": "https://www.usap-dc.org/view/dataset/600043"}], "date_created": "Mon, 04 May 2009 00:00:00 GMT", "description": "Phaeocystis Antarctica is a widely distributed phytoplankton that forms dense blooms and aggregates in the Southern Ocean. This phytoplankton and plays important roles in polar ecology and biogeochemistry, in part because it is a dominant primary producer, a main component of organic matter vertical fluxes, and the principal producer of volatile organic sulfur in the region. Yet P. Antarctica is also one of the lesser known species in terms of its physiology, life history and trophic relationships with other organisms; furthermore, information collected on other Phaeocystis species and from different locations may not be applicable to P. Antarctica in the Ross Sea. P. Antarctica occurs mainly as two morphotypes: solitary cells and mucilaginous colonies, which differ significantly in size, architecture and chemical composition. Relative dominance between solitary cells and colonies determines not only the size spectrum of the population, but also its carbon dynamics, nutrient uptake and utilization. Conventional thinking of the planktonic trophic processes is also challenged by the fact that colony formation could effectively alter the predator-prey interactions and interspecific competition. However, the factors that regulate the differences between solitary and colonial forms of P. Antarctica are not well-understood. The research objective of this proposal is therefore to address these over-arching questions:\u003cbr/\u003eo Do P. Antarctica solitary cells and colonies differ in growth, composition and\u003cbr/\u003ephotosynthetic rates?\u003cbr/\u003eo How do nutrients and grazers affect colony development and size distribution of P. \u003cbr/\u003eAntarctica?\u003cbr/\u003eo How do nutrients and grazers act synergistically to affect the long-term population\u003cbr/\u003edynamics of P. Antarctica? Experiments will be conducted in the McMurdo station with natural P. Antarctica assemblages and co-occurring grazers. Laboratory experiments will be conducted to study size-specific growth and photosynthetic rates of P. Antarctica, size-specific grazing mortality due to microzooplankton and mesozooplankton, the effects of macronutrients on the (nitrogen compounds) relative dominance of solitary cells and colonies, and the effects of micronutrient (Fe) and grazing related chemical signals on P. Antarctica colony development. Because this species is of critical importance in the Southern Ocean, and because this research will provide critical information on factors that regulate the role of P.Antarctica in food webs and biogeochemical cycles, a major gap in knowledge will be addressed. This project will train two marine science PhD students. The investigators will also collaborate with the School of Education and a marine science museum to communicate polar science to a broader audience.", "east": 166.66267, "geometry": "POINT(166.66267 -77.85067)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.85067, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Tang, Kam; Smith, Walker", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.85067, "title": "Environmental and Ecological Regulation of Differences and Interactions between Solitary and Colonial forms of Phaeocystis antarctica", "uid": "p0000214", "west": 166.66267}, {"awards": "0338363 Thiemens, Mark; 0337933 Cole-Dai, Jihong", "bounds_geometry": null, "dataset_titles": "Major Ion Concentrations in 2004 South Pole Ice Core", "datasets": [{"dataset_uid": "609542", "doi": "10.7265/N5HX19N8", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Ion Chromatograph; South Pole", "people": "Cole-Dai, Jihong", "repository": "USAP-DC", "science_program": null, "title": "Major Ion Concentrations in 2004 South Pole Ice Core", "url": "https://www.usap-dc.org/view/dataset/609542"}], "date_created": "Fri, 11 Aug 2006 00:00:00 GMT", "description": "This award supports a collaborative study between South Dakota State University (SDSU) and University of California, San Diego (UCSD) to investigate the oxygen and sulfur isotope composition of sulfates from a number of large volcanic eruptions in the past 1000 years. The project aims to drill a number of shallow ice cores at South Pole and return them to SDSU and UCSD lab for chemical and isotope analysis. Preliminary results from measurements of isotopes in sulfate samples from several volcanic eruptions in Antarctic snow and ice indicate that isotopic composition of volcanic sulfate contains abundant valuable information on atmospheric chemical and dynamic processes that have not been previously investigated. One tentative conclusion is that mass-independently fractionated sulfur isotopes reveal that atmospheric photolysis of sulfur compounds occurs at longer UV wavelengths than those in the Archean atmosphere, possibly reflecting the atmospheric ozone and/or oxygen concentration. This suggests that isotopic composition of atmospheric sulfate may be used to understand the role of UV radiation in sulfur dioxide conversion in the atmosphere and to track the evolution (i.e., oxygenation) of the atmosphere and the origin of life on Earth. Other major research objectives include understanding what impact massive volcanic eruptions have on the oxidative capacity of the atmosphere, what oxidants and mechanisms are involved in the oxidation or conversion of volcanic sulfur dioxide to sulfate in the stratosphere and what isotopic criteria may be used to differentiate ice core signals of stratospheric eruptions from those of tropospheric eruptions. By providing educational and research opportunities to graduate and undergraduate students at both SDSU and UCSD, the proposed project will promote the integration of research and education and contribute to human resource development in science and engineering. The project will contribute to a proposed REU chemistry site program at SDSU. This collaboration will utilize the complementary strengths of both labs and promote exchange between the two institutions. International collaboration will enhance scientific cooperation between France and US.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ION CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Not provided; Ion Chromatograph; Ions; LABORATORY; GROUND-BASED OBSERVATIONS", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Cole-Dai, Jihong", "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": "Collaborative Research: Investigating Atmospheric Chemistry and Dynamics through Oxygen and Sulfur Isotopes in Volcanic Sulfate from South Pole Ice Cores", "uid": "p0000031", "west": null}, {"awards": "0338359 Saltzman, Eric", "bounds_geometry": "POINT(-148.81 -81.65)", "dataset_titles": "Analysis of Siple Dome Ice Core: Carbonyl Sulfide (COS), Methyl Chloride (CH3Cl), and Methyl Bromide (CH3Br); Antarctic Ice Cores: Methyl Chloride and Methyl Bromide; Ice Core Air Carbonyl Sulfide Measurements - SPRESSO Ice Core; Methane and Carbonyl Sulfide Analysis of Siple Dome Ice Core Subsamples", "datasets": [{"dataset_uid": "609279", "doi": "10.7265/N53B5X3G", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Aydin, Murat; Saltzman, Eric", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Analysis of Siple Dome Ice Core: Carbonyl Sulfide (COS), Methyl Chloride (CH3Cl), and Methyl Bromide (CH3Br)", "url": "https://www.usap-dc.org/view/dataset/609279"}, {"dataset_uid": "609131", "doi": "10.7265/N5P848VP", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Methane; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Methane and Carbonyl Sulfide Analysis of Siple Dome Ice Core Subsamples", "url": "https://www.usap-dc.org/view/dataset/609131"}, {"dataset_uid": "601357", "doi": "10.15784/601357", "keywords": "Antarctica; Atmospheric Gases; Gas Measurement; Ice Core; Ice Core Gas Records; Trace Gases", "people": "Saltzman, Eric; Aydin, Murat", "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": "609313", "doi": "10.7265/N5DN430Q", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core; Ice Core Records; ITASE; Paleoclimate; Siple Dome Ice Core; South Pole; SPRESSO; SPRESSO Ice Core", "people": "Williams, Margaret; Tatum, Cheryl; Saltzman, Eric; Aydin, Murat", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Ice Cores: Methyl Chloride and Methyl Bromide", "url": "https://www.usap-dc.org/view/dataset/609313"}], "date_created": "Wed, 16 Nov 2005 00:00:00 GMT", "description": "This award supports the analysis, in Antarctic ice cores, of the ozone depleting substances methyl bromide (CH3Br) and methyl chloride (CH3Cl), and the sulfur-containing gas, carbonyl sulfide (OCS). The broad scientific goal is to assess the level and variability of these gases in the preindustrial atmosphere. This information will allow testing of current models for sources and sinks of these gases from the atmosphere, and to indirectly assess the impact of anthropogenic activities on their biogeochemical cycles. Longer-term records will shed light on the climatic sensitivity of the atmospheric burden of these gases, and ultimately on the biogeochemical processes controlling them. These gases are present in ice at parts per trillion levels, and the current database consists entirely of a small number of measurements made in from a shallow ice core from Siple Dome, Antarctica. This project will involve studies of ice core samples from three Antarctic sites: Siple Station, Siple Dome, and South Pole. The sampling strategy is designed to accomplish several objectives: 1) to verify the atmospheric mixing ratios previously observed in shallow Siple Dome ice for OCS, CH3Br, and CH3Cl at sites with very different accumulation rates and surface temperatures; 2) to obtain a well-dated, high resolution record from a high accumulation rate site (Siple Station), that can provide overlap in mean gas age with Antarctic firn air samples; 3) explore Holocene variability in trace gas mixing ratios; and 4) to make the first measurements of these trace gases in Antarctic glacial ice. In terms of broader impact on society, this research will help to provide a stronger scientific basis for policy decisions regulating the production and use of ozone-depleting and climate-active gases. Specifically, the methyl bromide results will contribute to the current debate on the impact of recent regulation (via the Montreal Protocol and its Amendments) on atmospheric levels. Determination of pre-industrial atmospheric variability of ozone-depleting substances will help place more realistic constraints on scenarios used for future projections of stratospheric ozone and its climatic impacts. This research will involve the participation of both graduate and undergraduate students.", "east": -148.81, "geometry": "POINT(-148.81 -81.65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e GAS CHROMATOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Ice Core Gas Records; Carbonyl Sulfide; Siple Coast; Chloride; Trapped Gases; Snow; Ice Core Chemistry; Chromatography; Siple; GROUND STATIONS; Atmospheric Gases; Ozone Depletion; AWS Siple; Ice Sheet; Ice Core Data; Antarctica; Glaciology; West Antarctica; Atmospheric Chemistry; Ice Core; Stratigraphy; LABORATORY; Methane; Mass Spectrometer; GROUND-BASED OBSERVATIONS; WAISCORES; Msa; Mass Spectrometry; Not provided; Siple Dome; Gas Measurement", "locations": "Antarctica; Siple Coast; Siple Dome; West Antarctica; Siple", "north": -81.65, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Saltzman, Eric; Aydin, Murat; Williams, Margaret; Tatum, Cheryl", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.65, "title": "Methyl chloride and methyl bromide in Antarctic ice cores", "uid": "p0000032", "west": -148.81}, {"awards": "9615333 Saltzman, Eric", "bounds_geometry": "POINT(-148.8 -81.7)", "dataset_titles": "Biogenic Sulfur in the Siple Dome Ice Core", "datasets": [{"dataset_uid": "609201", "doi": "10.7265/N5S180F1", "keywords": "Antarctica; Biota; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Saltzman, Eric; Dioumaeva, Irina; Finley, Brandon", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Biogenic Sulfur in the Siple Dome Ice Core", "url": "https://www.usap-dc.org/view/dataset/609201"}], "date_created": "Tue, 09 Mar 2004 00:00:00 GMT", "description": "This award is for support for four years of funding for a program of biogenic sulfur measurements on the Siple Dome ice core. Biogenic sulfur is a major aerosol-forming constituent of the atmosphere and has potentially important links to the earth\u0027s radiation budget. Previous work on the Vostok ice core has demonstrated a remarkable climate-related variability in biogenic sulfur, suggesting that the sulfur cycle may act to stabilize climate (keep the glacial atmosphere cool and the interglacial atmosphere warm) in the Southern Hemisphere. In this study, methane-sulfonate (MSA) will be measured on the Siple Dome ice core as part of the West Antarctic ice sheet program (WAIS). Siple Dome is located in a region which is strongly impacted by the incursion of marine air onto the Antarctic plateau. Because of its proximity to the coast and meteorological setting, it is expected that variability in high-latitude marine biogenic sulfur emissions should dominate the MSA record at this site. In addition to the deep ice core record, samples from shallow cores will also be analyzed to provide information about regional variability and decadal-to-centennial scale variability in the deposition of sulfur-containing aerosols from high latitude source regions over the past 200 years.", "east": -148.8, "geometry": "POINT(-148.8 -81.7)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "FIELD SURVEYS; Siple Dome; GROUND-BASED OBSERVATIONS; Biogenic Sulfur; FIELD INVESTIGATION; Not provided; LABORATORY; Methane Sulfonate", "locations": "Siple Dome", "north": -81.7, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Saltzman, Eric; Dioumaeva, Irina; Finley, Brandon", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; 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": "Siple Dome Ice Core", "south": -81.7, "title": "Biogenic Sulfur in the Siple Dome Ice Core", "uid": "p0000251", "west": -148.8}, {"awards": "9615167 Dunbar, Nelia; 9527373 Dunbar, Nelia", "bounds_geometry": null, "dataset_titles": "Blue Ice Tephra II - Brimstone Peak; Blue Ice Tephra II - Mt. DeWitt; Tephra in Siple and Taylor Dome Ice Cores; Volcanic Records in the Siple and Taylor Dome Ice Cores", "datasets": [{"dataset_uid": "609110", "doi": "10.7265/N50P0WXF", "keywords": "Antarctica; Backscattered Electron Images; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Siple Dome; Siple Dome Ice Core; Taylor Dome Ice Core; WAIS", "people": "Dunbar, Nelia", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Tephra in Siple and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609110"}, {"dataset_uid": "609126", "doi": "10.7265/N5FQ9TJG", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome Ice Core; Taylor Dome Ice Core; Tephra; WAIS; WAISCORES", "people": "Zielinski, Gregory; Dunbar, Nelia", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Volcanic Records in the Siple and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609126"}, {"dataset_uid": "609126", "doi": "10.7265/N5FQ9TJG", "keywords": "Antarctica; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; Siple Dome Ice Core; Taylor Dome Ice Core; Tephra; WAIS; WAISCORES", "people": "Zielinski, Gregory; Dunbar, Nelia", "repository": "USAP-DC", "science_program": "Taylor Dome Ice Core", "title": "Volcanic Records in the Siple and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609126"}, {"dataset_uid": "609114", "doi": "10.7265/N5MG7MDK", "keywords": "Antarctica; Blue Ice; Brimstone Peak; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Petrography; Tephra", "people": "Dunbar, Nelia", "repository": "USAP-DC", "science_program": null, "title": "Blue Ice Tephra II - Brimstone Peak", "url": "https://www.usap-dc.org/view/dataset/609114"}, {"dataset_uid": "609115", "doi": "10.7265/N5GQ6VPV", "keywords": "Antarctica; Blue Ice; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Mount Dewitt; Petrography; Tephra", "people": "Dunbar, Nelia", "repository": "USAP-DC", "science_program": null, "title": "Blue Ice Tephra II - Mt. DeWitt", "url": "https://www.usap-dc.org/view/dataset/609115"}, {"dataset_uid": "609110", "doi": "10.7265/N50P0WXF", "keywords": "Antarctica; Backscattered Electron Images; Chemistry:rock; Chemistry:Rock; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Siple Dome; Siple Dome Ice Core; Taylor Dome Ice Core; WAIS", "people": "Dunbar, Nelia", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Tephra in Siple and Taylor Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609110"}], "date_created": "Sat, 01 Jun 2002 00:00:00 GMT", "description": "Dunbar/Kyle OPP 9527373 Zielinski OPP 9527824 Abstract The Antarctic ice sheets are ideal places to preserve a record the volcanic ash (tephra) layers and chemical aerosol signatures of volcanic eruptions. This record, which is present both in areas of bare blue ice, as well as in deep ice cores, consists of a combination of local eruptions, as well as eruptions from more distant volcanic sources from which glassy shards can be chemically fingerprinted and related to a source volcano. Field work carried out during the 1994/1995 Antarctic field season in the Allan Hills area of Antarctica, and subsequent microbeam chemical analysis and 40Ar/39Ar dating has shown that tephra layers in deep Antarctic ice preserve a coherent, systematic stratigraphy, and can be successfully mapped, dated, chemically fingerprinted and tied to source volcanoes. The combination of chemical fingerprinting of glass shards, and chemical analysis of volcanic aerosols associated with ash layers will allow establishment of a high-resolution chronology of local and distant volcanism that can help understand patterns of significant explosive volcanisms and atmospheric loading and climactic effects associated with volcanic eruptions. Correlation of individual tephra layers, or sets of layers, in blue ice areas, which have been identified in many places the Transantarctic Mountains, will allow the geometry of ice flow in these areas to be better understood and will provide a useful basis for interpreting ice core records.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e PROBES \u003e ELECTRON MICROPROBES", "is_usap_dc": true, "keywords": "USAP-DC; Siple Coast; Sulfur Dioxide; Siple Dome; Taylor Dome; Chlorine; WAISCORES; Ice Core; Tephra; Geochemistry; Volcanic Deposits; GROUND STATIONS; Brimstone Peak; GROUND-BASED OBSERVATIONS; Magnesium Oxide; Glaciology; Mount Dewitt; Silicon Dioxide; Glass Shards; Ice Sheet; Siple; Nickel Oxide; Potassium Dioxide; Not provided; Manganese Oxide; Volcanic; Snow; Nitrogen; Iron Oxide; Titanium Dioxide; Stratigraphy; Antarctica", "locations": "Antarctica; Siple; Siple Coast; Siple Dome; Taylor Dome; Brimstone Peak; Mount Dewitt", "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Dunbar, Nelia; Zielinski, Gregory", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Taylor Dome Ice Core", "south": null, "title": "Collaborative Research: Volcanic Record in Antarctic Ice: Implications for Climatic and Eruptive History and Ice Sheet Dynamics of the South Polar Region", "uid": "p0000065", "west": null}]

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