USAP-DC

{"dp_type": "Project", "free_text": "organic matter"}

[{"awards": "2147045 Learman, Deric", "bounds_geometry": "POLYGON((-180 -60,-168 -60,-156 -60,-144 -60,-132 -60,-120 -60,-108 -60,-96 -60,-84 -60,-72 -60,-60 -60,-60 -62,-60 -64,-60 -66,-60 -68,-60 -70,-60 -72,-60 -74,-60 -76,-60 -78,-60 -80,-72 -80,-84 -80,-96 -80,-108 -80,-120 -80,-132 -80,-144 -80,-156 -80,-168 -80,180 -80,171 -80,162 -80,153 -80,144 -80,135 -80,126 -80,117 -80,108 -80,99 -80,90 -80,90 -78,90 -76,90 -74,90 -72,90 -70,90 -68,90 -66,90 -64,90 -62,90 -60,99 -60,108 -60,117 -60,126 -60,135 -60,144 -60,153 -60,162 -60,171 -60,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Tue, 30 Aug 2022 00:00:00 GMT", "description": "Microbes in Antarctic surface marine sediments have an important role in degrading organic matter and releasing nutrients to the ocean. Organic matter degradation is at the center of the carbon cycle in the ocean, providing valuable information on nutrient recycling, food availability to animals and carbon dioxide release to the atmosphere. The functionality of these microbes has been inferred by their genomics, however these methods only address the possible function, not their actual rates. In this project the PIs plan to combine genomics methods with cellular estimates of enzyme abundance and activity as a way to determine the rates of carbon degradation. This project aims to sample in several regions of Antarctica to provide a large-scale picture of the processes under study and understand the importance of microbial community composition and environmental factors, such as primary productivity, have on microbial activity. The proposed work will combine research tools such as metagenomics, meta-transcriptomics, and metabolomics coupled with chemical data and enzyme assays to establish degradation of organic matter in Antarctic sediments. This project benefits NSFs goals of understanding the adaptation of Antarctic organisms to the cold and isolated environment, critical to predict effects of climate change to polar organisms, as well as contribute to our knowledge of how Antarctic organisms have adapted to this environment. Society will benefit from this project by education of 2 graduate students, undergraduates and K-12 students as well as increase public literacy through short videos production shared in YouTube.\r\n\r\nThe PIs propose to advance understanding of polar microbial community function, by measuring enzyme and gene function of complex organic matter degradation in several ocean regions, providing a circum-Antarctic description of sediment processes. Two hypotheses are proposed. The first hypothesis states that many genes for the degradation of complex organic matter will be shared in sediments throughout a sampling transect and that where variations in gene content occur, it will reflect differences in the quantity and quality of organic matter, not regional variability. The second hypothesis states that a fraction of gene transcripts for organic matter degradation will not result in measurable enzyme activity due to post-translational modification or rapid degradation of the enzymes. The PIs will analyze sediment cores already collected in a 2020 cruise to the western Antarctic Peninsula with the additional request of participating in a cruise in 2023 to East Antarctica. The PIs will analyze sediments for metagenomics, meta-transcriptomics, and metabolomics coupled with geochemical data and enzyme assays to establish microbial degradation of complex organic matter in Antarctic sediments. Organic carbon concentrations and content in sediments will be measured with \u03b413C, \u03b415N, TOC porewater fluorescence in bulk organic carbon. Combined with determination of geographical variability as well as dependence on carbon sources, results from this study could provide the basis for new hypotheses on how climate variability, with increased water temperature, affects geochemistry in the Southern Ocean.", "east": 90.0, "geometry": "POINT(-165 -70)", "instruments": null, "is_usap_dc": true, "keywords": "SEDIMENT CHEMISTRY; BENTHIC; ECOSYSTEM FUNCTIONS; R/V NBP; Weddell Sea; Antarctic Peninsula", "locations": "Antarctic Peninsula; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Learman, Deric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repositories": null, "science_programs": null, "south": -80.0, "title": "Collaborative Research: ANT LIA: Connecting Metagenome Potential to Microbial Function: Investigating Microbial Degradation of Complex Organic Matter Antarctic Benthic Sediments", "uid": "p0010373", "west": -60.0}, {"awards": "1847067 Levy, Joseph", "bounds_geometry": "POLYGON((161 -76,161.35 -76,161.7 -76,162.05 -76,162.4 -76,162.75 -76,163.1 -76,163.45 -76,163.8 -76,164.15 -76,164.5 -76,164.5 -76.2,164.5 -76.4,164.5 -76.6,164.5 -76.8,164.5 -77,164.5 -77.2,164.5 -77.4,164.5 -77.6,164.5 -77.8,164.5 -78,164.15 -78,163.8 -78,163.45 -78,163.1 -78,162.75 -78,162.4 -78,162.05 -78,161.7 -78,161.35 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76))", "dataset_titles": "Biogeochemical measurements of water tracks and adjacent dry soils from the McMurdo Dry Valleys", "datasets": [{"dataset_uid": "601684", "doi": "10.15784/601684", "keywords": "Antarctica; Cation Exchange; Chemistry:Soil; Cryosphere; Dry Valleys; organic matter; Salt; Soil", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemical measurements of water tracks and adjacent dry soils from the McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601684"}], "date_created": "Fri, 24 Dec 2021 00:00:00 GMT", "description": "Antarctic groundwater drives the regional carbon cycle, accelerates permafrost thaw, and shapes Antarctic climate response. However, groundwater extent, movement, and processes on a continent virtually locked in ice are poorly understood. The proposed work investigates the interplay between groundwater, sediment, and ice in Antarctica\u2019s cold desert landscapes to determine when, where, and why Antarctic groundwater is flowing, and how quickly it will switch Antarctic frozen deserts from dry and stable to wet and disintegrating. Little is known about the extent, chemistry, and duration of groundwater in Antarctic seasonal wetlands. Mapping the changing extent of Antarctic wetlands requires the ability to measure soil moisture rapidly and repeatedly and over large areas. Changing groundwater extent will be captured through an unmanned aerial vehicle (UAV)-based mapping approach. The project integrates a diverse range of sensors with new UAV technologies to provide a higher-resolution and more frequent assessment of Antarctic groundwater extent and composition than can be accomplished using satellite observations alone. To complement the research objectives, the PI will develop a new UAV summer field school, the Geosciences UAV Academy, focused on training undergraduate-level UAV pilots in conducting novel Earth science research using cutting edge imaging tools. The integration of research and technology will prepare students for careers in burgeoning UAV-related industries and research. The project will deliver new UAV tools and workflows for soil moisture mapping relevant to arid regions common not just to Antarctica but to temperate desert and dryland systems and will train student research pilots to tackle next generation airborne challenges. \r\n\r\nWater tracks are the basic hydrological unit that currently feeds the rapidly-changing polar and permafrost wetlands in the Antarctic McMurdo Dry Valleys (MDV). Despite the importance of water tracks in the MDV hydrologic cycle and their influence on biogeochemistry, little is known about how these water tracks control the unique brine processes operating in Antarctic ice-free areas. Both groundwater availability and geochemistry shape Antarctic microbial communities, connecting soil geology and hydrology to carbon cycling and ecosystem functioning. The objectives of this CAREER proposal are to 1) map water tracks to determine the spatial distribution and seasonal magnitude of groundwater impacts on the MDV near-surface environment to determine how water tracks drive irreversible permafrost thaw, how water tracks enhance chemical weathering and biogeochemical cycling, and how water tracks integrate and accelerate climate feedbacks between terrestrial Antarctic soils and the Southern Ocean; 2) establish a UAV academy training earth sciences students to answer geoscience questions using drone-based platforms and remote sensing techniques; and 3) provide a formative step in the development of the PI as a teacher-scholar. UAV-borne hyperspectral imaging complemented with field soil sampling will determine the aerial extent and timing of inundation, water level, and water budget of representative water tracks in the MDV. Soil moisture will be measured via near-infrared reflectance spectroscopy while bulk chemistry of soils and groundwater will be analyzed via ion chromatography and soil x-ray fluorescence. Sedimentological and hydrological properties (suction/matric potential, hydraulic conductivity, etc.) will be determined via analysis of intact core samples. These data will be used to test competing hypotheses regarding the origin of water track solutions and water movement through seasonal wetlands. The will provide a regional understanding of Antarctic groundwater sources, groundwater flux, and the influence of regional hydrogeology on solute export to the Southern Ocean and on soil/atmosphere linkages in earth\u2019s carbon budget. The UAV school will 1) provide comprehensive instruction at the undergraduate level in both how and why UAVs can be used in geoscience research and learning; and 2) provide a long-term piece of educational infrastructure in the form of an ultimately self-sustaining summer program for undergraduate UAV education. \r\n", "east": 164.5, "geometry": "POINT(162.75 -77)", "instruments": null, "is_usap_dc": true, "keywords": "USA/NSF; FIELD SURVEYS; AMD/US; AMD; USAP-DC; FROZEN GROUND; Taylor Valley", "locations": "Taylor Valley", "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Levy, Joseph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Linking Antarctic Cold Desert Groundwater to Thermokarst \u0026 Chemical Weathering in Partnership with the Geoscience UAV Academy", "uid": "p0010286", "west": 161.0}, {"awards": "1941327 Stammerjohn, Sharon; 1941304 Sherrell, Robert; 1941292 St-Laurent, Pierre; 1941483 Yager, Patricia; 1941308 Fitzsimmons, Jessica", "bounds_geometry": "POLYGON((-120 -71,-118 -71,-116 -71,-114 -71,-112 -71,-110 -71,-108 -71,-106 -71,-104 -71,-102 -71,-100 -71,-100 -71.4,-100 -71.8,-100 -72.2,-100 -72.6,-100 -73,-100 -73.4,-100 -73.8,-100 -74.2,-100 -74.6,-100 -75,-102 -75,-104 -75,-106 -75,-108 -75,-110 -75,-112 -75,-114 -75,-116 -75,-118 -75,-120 -75,-120 -74.6,-120 -74.2,-120 -73.8,-120 -73.4,-120 -73,-120 -72.6,-120 -72.2,-120 -71.8,-120 -71.4,-120 -71))", "dataset_titles": "Expedition Data of NBP2202", "datasets": [{"dataset_uid": "200311", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP2202", "url": "https://www.rvdata.us/search/cruise/NBP2202"}], "date_created": "Fri, 20 Aug 2021 00:00:00 GMT", "description": " The Amundsen Sea hosts the most productive polynya in all of Antarctica, with its vibrant green waters visible from space, and an atmospheric CO2 uptake density 10x higher than the Southern Ocean average. The region is vulnerable to climate change, experiencing rapid losses in sea ice, a changing icescape, and some of the fastest melting glaciers flowing from the West Antarctic Ice Sheet (WAIS). ARTEMIS aims to characterize the climate-sensitive nature of glacial meltwater-driven micronutrient (iron, Fe) contributions driving ecosystem productivity and CO2 uptake in the coastal Antarctic. We propose to integrate observations and ocean modeling of these processes to enhance predictive capabilities. Currently, basal melt resulting from warm deep waters penetrating ice shelf cavities dominates mass losses of WAIS, contributing to sea level rise. These physical melting processes are being studied by the International Thwaites Glacier Collaboration (ITGC). The impact of melting on the marine ecosystem has also been explored, and we know that productivity is due in part to Fe-rich, glacial meltwater-driven outflow. The biogeochemical composition of the outflow from the glaciers surrounding the Amundsen Sea is largely unstudied, however. Improved knowledge would provide keys to understanding meltwater\u0027s future impact on the ecosystem. An ongoing field program (TARSAN, part of the ITGC) offers the ideal physical oceanographic framework for our biogeochemical effort. We propose here to collaborate with TARSAN-supported UK scientists, providing value added to both team efforts. ARTEMIS will add shipboard measurements (trace metals, carbonate system, nutrients, organic matter, microorganisms) and biogeochemical sensors on autonomous vehicles to gather critical knowledge needed to understand the impact of the melting WAIS on both the coastal ecosystem and the regional carbon (C) cycle. Driving questions include: 1) what are the fluxes and chemical forms of Fe, C, and microorganisms in the ice shelf outflow? 2) what are the relative contributions to the ouflow from deep water, benthic, and glacial melt sources, and how do these inputs combine to affect the bioavailability of Fe? 3) How are Fe and C compounds modified as the outflow advects along the coastal current and mixes into the bloom region? and 4) what will be the effect of increased glacial melting, changes in the coastal icescape, and declining sea ice on theecosystem of the Amundsen Sea? Such questions fall outside the focus of the ITGC, but are of keen interest to Antarctic Organisms and Ecosystems and Antarctic Integrated System Science programs.", "east": -100.0, "geometry": "POINT(-110 -73)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; Amundsen Sea; AMD/US; BIOGEOCHEMICAL CYCLES; SHIPS; USA/NSF; USAP-DC", "locations": "Amundsen Sea", "north": -71.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Yager, Patricia; Medeiros, Patricia; Sherrell, Robert; St-Laurent, Pierre; Fitzsimmons, Jessica; Stammerjohn, Sharon", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "Other", "science_programs": "Thwaites (ITGC)", "south": -75.0, "title": "NSFGEO-NERC: Collaborative Research: Accelerating Thwaites Ecosystem Impacts for the Southern Ocean (ARTEMIS)", "uid": "p0010249", "west": -120.0}, {"awards": "2031442 Learman, Deric", "bounds_geometry": "POLYGON((-180 -60,-167.5 -60,-155 -60,-142.5 -60,-130 -60,-117.5 -60,-105 -60,-92.5 -60,-80 -60,-67.5 -60,-55 -60,-55 -62,-55 -64,-55 -66,-55 -68,-55 -70,-55 -72,-55 -74,-55 -76,-55 -78,-55 -80,-67.5 -80,-80 -80,-92.5 -80,-105 -80,-117.5 -80,-130 -80,-142.5 -80,-155 -80,-167.5 -80,180 -80,178 -80,176 -80,174 -80,172 -80,170 -80,168 -80,166 -80,164 -80,162 -80,160 -80,160 -78,160 -76,160 -74,160 -72,160 -70,160 -68,160 -66,160 -64,160 -62,160 -60,162 -60,164 -60,166 -60,168 -60,170 -60,172 -60,174 -60,176 -60,178 -60,-180 -60))", "dataset_titles": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "datasets": [{"dataset_uid": "601607", "doi": "10.15784/601607", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Grain Size; Grain Size Analysis; Marine Geoscience; Marine Sediments; Organic Matter Geochemistry; Sediment Core Data; Shelf Sediments; Weddell Sea", "people": "Learman, Deric", "repository": "USAP-DC", "science_program": null, "title": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "url": "https://www.usap-dc.org/view/dataset/601607"}], "date_created": "Wed, 28 Jul 2021 00:00:00 GMT", "description": "This proposal will provide genetic and enzymatic insight into how microbial communities in benthic sediments on the coastal shelf of Antarctica degrade complex organic matter. The current understanding of how benthic microbial communities respond and also degrade complex organic matter in Antarctica is fragmented. Recent work suggests benthic microbial communities are shaped by organic matter availability (encompassing both quantity and quality), however, these studies were observational and did not directly examine community function (e.g. enzyme activity and/or gene expression). Preliminary metagenomic data, collected from western Antarctica marine sediments, document gene potential for organic matter degradation throughout the entire sample set (spanning the Amundsen Sea, Bellingshausen Sea, and Ross Sea), but functional data was not collected. To date, studies have examined either enzyme activity or metagenomic potential but few have been able to directly connect the two. To address these gaps in knowledge, this proposal will utilize powerful tools such as metagenomics and metatranscriptomics, coupled with microcosm experiments, enzyme assays, and geochemical data. This hypothesis driven proposal will examine microbial communities from the continental shelf of Antarctica from two different regions (Bransfield Strait and Weddell Sea) to document the communities\u2019 enzymatic activity and genes used to degrade complex organic matter. These data will expand our current knowledge of genetic potential towards a more direct understanding of enzyme function as it relates to degradation of complex organic matter in marine sediments from Antarctica. ", "east": 160.0, "geometry": "POINT(-127.5 -70)", "instruments": null, "is_usap_dc": true, "keywords": "ECOSYSTEM FUNCTIONS; SEDIMENT CHEMISTRY; USAP-DC; Antarctic Peninsula; AMD; USA/NSF; Weddell Sea; BENTHIC; SHIPS; AMD/US", "locations": "Antarctic Peninsula; Weddell Sea", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Learman, Deric", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.0, "title": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments", "uid": "p0010235", "west": -55.0}, {"awards": "2000992 Romans, Brian", "bounds_geometry": "POINT(-172.873074 -74.274008)", "dataset_titles": null, "datasets": null, "date_created": "Tue, 06 Jul 2021 00:00:00 GMT", "description": "Geological records from the Antarctic Ice Sheet (AIS) margin demonstrate that the ice sheet oscillated in response to orbital variations in insolation (i.e., ~400, 100, 41, and 20 kyr), and it appears to be more sensitive to specific frequencies that regulate mean annual insolation (i.e., 41-kyr obliquity), particularly when the ice sheet extends into marine environments and is impacted by ocean circulation. However, the relationship between orbital forcing and the production of Antarctic Bottom Water (AABW) is unconstrained. Thus, a knowledge gap exists in understanding how changing insolation impacts ice marginal and Southern Ocean conditions that directly influence ventilation of the global ocean. We hypothesize that insolation-driven changes directly affected the production and export of AABW to the Southern Ocean from the Pliocene through the Pleistocene. For example, obliquity amplification during the warmer Pliocene may have led to enhanced production and export of dense waters from the shelf due to reduced AIS extent, which, in turn, led to greater AABW outflow. To determine the relationship of AABW production to orbital regime, we plan to reconstruct both from a single, continuous record from the levee of Hillary Canyon, a major conduit of AABW outflow, on the Ross Sea continental rise. \r\n\r\nTo test our hypothesis, we will analyze sediment from IODP Site U1524 (recovered in 2018 during International Ocean Discovery Program Expedition 374) and focus on three data sets. (1) We will use the occurrence, frequency, and character of mm-scale turbidite beds as a proxy of dense-shelf-water cascading outflow and AABW production. We will estimate the down-slope flux via numerical modeling of turbidity current properties using morphology, grain size, and bed thickness as input parameters. (2) We will use grain-size data, physical properties, XRF core scanning, CT imaging, and hyperspectral imaging to guide lithofacies analysis to infer processes occurring during glacial, deglacial, and interglacial periods. Statistical techniques and optimization methods will be applied to test for astronomical forcing of sedimentary packages in order to provide a cyclostratigraphic framework and interpret the orbital-forcing regime. (3) We will use bulk sedimentary carbon and nitrogen abundance and isotope data to determine how relative contributions of terrigenous and marine organic matter change in response to orbital forcing. We will integrate these data with sedimentological records to deconvolve organic matter production from its deposition or remobilization due to AABW outflow as a function of the oscillating extent of the AIS. These data sets will be integrated into a unified chronostratigraphy to determine the relationship between AABW outflow and orbital-forcing scenarios under the varying climate regimes of the Plio-Pleistocene.\r\n", "east": -172.873074, "geometry": "POINT(-172.873074 -74.274008)", "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; LABORATORY; USA/NSF; SEDIMENTS; AMD/US; AMD; Ross Sea", "locations": "Ross Sea", "north": -74.274008, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Romans, Brian; Patterson, Molly; Ash, Jeanine; Kulhanek, Denise; Ash, Jeannie", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -74.274008, "title": "COLLABORATIVE RESEARCH: Orbital-scale Variability of the West Antarctic Ice Sheet and the Formation of Bottom Water in the Ross Sea during the Pliocene-Pleistocene", "uid": "p0010227", "west": -172.873074}, {"awards": "1341376 Tabor, Neil; 1341645 Makovicky, Peter; 1341304 Sidor, Christian; 1341475 Smith, Nathan; 2001033 Makovicky, Peter", "bounds_geometry": "POLYGON((-180 -84,-178 -84,-176 -84,-174 -84,-172 -84,-170 -84,-168 -84,-166 -84,-164 -84,-162 -84,-160 -84,-160 -84.3,-160 -84.6,-160 -84.9,-160 -85.2,-160 -85.5,-160 -85.8,-160 -86.1,-160 -86.4,-160 -86.7,-160 -87,-162 -87,-164 -87,-166 -87,-168 -87,-170 -87,-172 -87,-174 -87,-176 -87,-178 -87,180 -87,178.5 -87,177 -87,175.5 -87,174 -87,172.5 -87,171 -87,169.5 -87,168 -87,166.5 -87,165 -87,165 -86.7,165 -86.4,165 -86.1,165 -85.8,165 -85.5,165 -85.2,165 -84.9,165 -84.6,165 -84.3,165 -84,166.5 -84,168 -84,169.5 -84,171 -84,172.5 -84,174 -84,175.5 -84,177 -84,178.5 -84,-180 -84))", "dataset_titles": "Lower Triassic Antarctic vertebrate fossils at Field Museum, Chicago, IL", "datasets": [{"dataset_uid": "601511", "doi": "10.15784/601511", "keywords": "Allan Hills; Antarctica; Cryosphere; Fremouw Formation; Lystrosaurus; Permo-Triassic Extinction; Prolacerta; Sample Location; Thrinaxofon; Triassic", "people": "Makovicky, Peter", "repository": "USAP-DC", "science_program": null, "title": "Lower Triassic Antarctic vertebrate fossils at Field Museum, Chicago, IL", "url": "https://www.usap-dc.org/view/dataset/601511"}], "date_created": "Tue, 29 Jun 2021 00:00:00 GMT", "description": "This project will advance our understanding of Antarctic life during the Permian and Triassic. We will apply an interdisciplinary approach to address relationships between environmental change, faunal composition, and biogeographic patterns in the context of the high-latitude strata preserved in the Buckley and Fremouw formations in the Shackleton Glacier region. We will use multiple types of data to assess paleoenvironment, including: 1) paleosol morphology; 2) paleosol geochemistry; 3) pedogenic organic matter; and 4) fossil wood chronology and stable isotopes. The Fremouw Formation of Antarctica preserves the highest paleolatitude tetrapod fauna of the entire Triassic (~70\u00b0 S) and thus has the potential to shed important light on the evolution of polar life during the early Mesozoic. We will collect new fossils from known localities to understand the relationship between Antarctic and southern African tetrapod faunas. Furthermore, we will refine the stratigraphic, sedimentological, and geochronological framework for these Mesozoic faunas, which will include using U/Pb detrital zircon dating to provide the first dates for these vertebrate assemblages. In the lab, we will examine the biology of Triassic vertebrates from Antarctica by comparing their bone and tusk histology to conspecifics from lower paleolatitudes. In addition, we will test Bergmann\u2019s Rule with six species (viz. Lystrosaurus curvatus, L. maccaigi, L. murrayi, Prolacerta broomi, Procolophon trigoniceps, and Thrinaxodon liorhinus). The Early Triassic presents a unique opportunity to perform such investigations as there is no other geologic interval in which species occurring in Antarctica can be compared to conspecifics across a range of paleolatitudes.", "east": -160.0, "geometry": "POINT(-177.5 -85.5)", "instruments": null, "is_usap_dc": true, "keywords": "REPTILES; FIELD SURVEYS; USAP-DC; TERRESTRIAL ECOSYSTEMS; MACROFOSSILS; Shackleton Glacier; fossils; USA/NSF; LAND RECORDS; AMD/US; ANIMALS/VERTEBRATES; PALEOCLIMATE RECONSTRUCTIONS; AMD; Triassic", "locations": "Shackleton Glacier", "north": -84.0, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": null, "persons": "Sidor, Christian; Smith, Nathan; Makovicky, Peter; Tabor, Neil", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.0, "title": "Collaborative Research: Understanding the evolution of high-latitude Permo-Triassic paleoenvironments and their vertebrate communities", "uid": "p0010213", "west": 165.0}, {"awards": "1643345 Popp, Brian; 1643466 Hollibaugh, James", "bounds_geometry": "POLYGON((-78.20206667 -64.03195833,-76.785055836 -64.03195833,-75.368045002 -64.03195833,-73.951034168 -64.03195833,-72.534023334 -64.03195833,-71.1170125 -64.03195833,-69.700001666 -64.03195833,-68.282990832 -64.03195833,-66.865979998 -64.03195833,-65.448969164 -64.03195833,-64.03195833 -64.03195833,-64.03195833 -64.554377497,-64.03195833 -65.076796664,-64.03195833 -65.599215831,-64.03195833 -66.121634998,-64.03195833 -66.644054165,-64.03195833 -67.166473332,-64.03195833 -67.688892499,-64.03195833 -68.211311666,-64.03195833 -68.733730833,-64.03195833 -69.25615,-65.448969164 -69.25615,-66.865979998 -69.25615,-68.282990832 -69.25615,-69.700001666 -69.25615,-71.1170125 -69.25615,-72.534023334 -69.25615,-73.951034168 -69.25615,-75.368045002 -69.25615,-76.785055836 -69.25615,-78.20206667 -69.25615,-78.20206667 -68.733730833,-78.20206667 -68.211311666,-78.20206667 -67.688892499,-78.20206667 -67.166473332,-78.20206667 -66.644054165,-78.20206667 -66.121634998,-78.20206667 -65.599215831,-78.20206667 -65.076796664,-78.20206667 -64.554377497,-78.20206667 -64.03195833))", "dataset_titles": "\"Collaborative research: Chemoautotrophy in Antarctic bacterioplankton communities supported by the oxidation of urea-derived nitrogen\"; Expedition data of LMG1801", "datasets": [{"dataset_uid": "200124", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1801", "url": "https://www.rvdata.us/search/cruise/LMG1801"}, {"dataset_uid": "200193", "doi": "Not yet assigned", "keywords": null, "people": null, "repository": "Biological \u0026 Chemical Oceanography Data Management Office (BCO_DMO)", "science_program": null, "title": "\"Collaborative research: Chemoautotrophy in Antarctic bacterioplankton communities supported by the oxidation of urea-derived nitrogen\"", "url": "https://www.bco-dmo.org/project/775717"}], "date_created": "Fri, 18 Dec 2020 00:00:00 GMT", "description": "The project addressed fundamental questions regarding the role of nitrification (the conversion of ammonium to nitrate by a two-step process involving two different guilds of microorganisms: ammonia- and nitrite-oxidizers) in the Antarctic marine ecosystem. Specifically, the project evaluated the contribution of carbon fixation supported by energy derived from the oxidation of nitrogen compounds (chemoautotrophy) to the overall supply of organic carbon to the food web of the Southern Ocean. Additionally, the project aimed to determine the significance of the contribution of other sources of reduced nitrogen, specifically organic nitrogen and urea, to nitrification because these contributions may not be assessed by standard protocols. \n\n\u003cbr\u003e\u003cbr\u003eWe quantified the oxidation rates of 15N supplied as ammonium, urea and nitrite, which allowed us to estimate the contribution of urea-derived N and complete nitrification (ammonia to nitrate, N-3 to N+5) to chemoautotrophy in Antarctic coastal waters. We compared these estimates to direct measurements of the incorporation of dissolved inorganic 14C into organic matter in the dark for an independent estimate of chemoautotrophy. We made measurements on samples taken from the major water masses: surface water (~10 m), winter water (35-174 m), circumpolar deep water (175-1000 m) and slope water (\u003e1000 m); on a cruise surveying the continental shelf and slope west of the Antarctic Peninsula in the austral summer of 2018 (LMG18-01). Samples were also taken to measure the concentrations of nitrite, ammonia, urea and polyamines; for qPCR analysis of the abundance of relevant marker genes; and for studies of processes related to the core questions of the study. The project relied on collaboration with the Palmer LTER for ancillary data (bacterioplankton abundance and production, chlorophyll, physical and additional chemical variables). The synergistic activities of this project along with the LTER activities provides a unique opportunity to assess chemoautotrophy in context of the overall ecosystem\u0027s dynamics, including both primary and secondary production processes.\n\u003cbr\u003e\u003cbr\u003eThis project resulted in the training of a postdoctoral researcher and provide undergraduate students opportunities to gain hand-on experience with research on microbial geochemistry. This project contributed substantially to understanding an important aspect of nitrogen cycling and bacterioplankton production in the study area. Both PIs participate fully in the education and outreach efforts of the Palmer LTER, including making highlights of the findings available for posting to the LTER project web site, posting material to web sites at their respective departments, and incorporating material from the study in lectures and seminars presented at their respective institutions. \n", "east": -64.03195833, "geometry": "POINT(-71.1170125 -66.644054165)", "instruments": null, "is_usap_dc": true, "keywords": "NITROGEN; SHIPS; BIOGEOCHEMICAL CYCLES; AMD/US; West Antarctic Shelf; USAP-DC; MARINE ECOSYSTEMS; USA/NSF; PAL-LTER; AMD; BACTERIA/ARCHAEA", "locations": "West Antarctic Shelf", "north": -64.03195833, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Hollibaugh, James T.; Popp, Brian", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e SHIPS", "repo": "R2R", "repositories": "Other", "science_programs": null, "south": -69.25615, "title": "Collaborative Research: Chemoautotrophy in Antarctic Bacterioplankton Communities Supported by the Oxidation of Urea-derived Nitrogen", "uid": "p0010150", "west": -78.20206667}, {"awards": "1543441 Fricker, Helen; 1543453 Lyons, W. Berry; 1543405 Leventer, Amy; 1543347 Rosenheim, Brad; 1543396 Christner, Brent; 1543537 Priscu, John", "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": "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": "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": "601661", "doi": "10.15784/601661", "keywords": "Antarctica; Carbon; Cryosphere; Glacier; Glaciers/Ice Sheet; Iron; Mercer Subglacial Lake; Mineralogy; Particle Size; physical properties; SALSA; Sediment Core; sulfur; West Antarctic Ice Sheet", "people": "Dore, John; Skidmore, Mark; Tranter, Martyn; Venturelli, Ryan A; Science Team, SALSA; Hawkings, Jon; Michaud, Alexander; Campbell, Timothy", "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": "601498", "doi": "10.15784/601498", "keywords": "Antarctica; Cryosphere; 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": "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": "601657", "doi": "10.15784/601657", "keywords": "Antarctica; Conductivity; Cryosphere; CTD; Depth; Glaciers/Ice Sheet; Glaciology; Hot Water Drill; Mercer Subglacial Lake; physical properties; SALSA; subglacial lake; Temperature", "people": "Priscu, John; Rosenheim, Brad; Leventer, Amy; Dore, John", "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": "601360", "doi": "10.15784/601360", "keywords": "Antarctica; Cryosphere; 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": "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": "601663", "doi": "10.15784/601663", "keywords": "Antarctica; Carbon; Cell Counts; Cryosphere; geochemistry; Glacier; Glaciers/Ice Sheet; Mercer Subglacial Lake; Microbes; Nutrients; SALSA; Stable Isotopes; Trace Elements; West Antarctic Ice Sheet", "people": "Skidmore, Mark; Science Team, SALSA; Priscu, John; Tranter, Martyn; Hawkings, Jon; Steigmeyer, August; Dore, John; Li, Wei; Barker, Joel", "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": "601472", "doi": "10.15784/601472", "keywords": "Antarctica; Bistatic Radar; Cryosphere; Glaciers/Ice Sheet; Glaciology; GPS Data; Greenland; Lake Whillans; Radar; Store Glacier; Whillans Ice Stream; WISSARD", "people": "Siegfried, Matthew; Christoffersen, Poul; Peters, Sean; MacKie, Emma; Bienert, Nicole; Schroeder, Dustin; Dawson, Eliza", "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": "601664", "doi": "10.15784/601664", "keywords": "Antarctica; Cryosphere; gases; geochemistry; Glacier; Glaciology; Mercer Subglacial Lake; Methane; SALSA; Sediment Core; West Antarctic Ice Sheet", "people": "Steigmeyer, August; Dore, John; Tranter, Martyn; Science Team, SALSA; Michaud, Alexander; Skidmore, Mark", "repository": "USAP-DC", "science_program": null, "title": "Sediment porewater properties data from Mercer Subglacial Lake", "url": "https://www.usap-dc.org/view/dataset/601664"}, {"dataset_uid": "601672", "doi": "10.15784/601672", "keywords": "Antarctica; Cryosphere; isotopes; Mercer Subglacial Lake; Radiocarbon; Subglacial lakes", "people": "Venturelli, Ryan; Rosenheim, Brad", "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": "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": "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": "200246", "doi": "", "keywords": null, "people": null, "repository": "OSU-MGR", "science_program": null, "title": "Salsa sediment cores", "url": "https://osu-mgr.org"}, {"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": "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"}], "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.\u003cbr/\u003e\u003cbr/\u003eSubglacial 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": "SALSA; SEDIMENTS; Antarctica; ISOTOPES; ECOSYSTEM FUNCTIONS; RADIOCARBON; FIELD INVESTIGATION; AMD/US; USAP-DC; VIRUSES; ICE MOTION; subglacial lake; PALEOCLIMATE RECONSTRUCTIONS; BACTERIA/ARCHAEA; LABORATORY; Radiocarbon; Mercer Ice Stream; USA/NSF; Whillans Ice Stream; AMD; GLACIERS/ICE SHEETS", "locations": "Antarctica; Mercer Ice Stream; Whillans Ice Stream", "north": -84.33543, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology; Antarctic Instrumentation and Support; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Rosenheim, Brad; Fricker, Helen; Priscu, John; Leventer, Amy; Dore, John; Lyons, W. Berry; Christner, Brent", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "UNAVCO", "repositories": "GenBank; Other; 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": "1544526 Omelon, Christopher", "bounds_geometry": "POLYGON((160 -76.5,160.37 -76.5,160.74 -76.5,161.11 -76.5,161.48 -76.5,161.85 -76.5,162.22 -76.5,162.59 -76.5,162.96 -76.5,163.33 -76.5,163.7 -76.5,163.7 -76.63,163.7 -76.76,163.7 -76.89,163.7 -77.02,163.7 -77.15,163.7 -77.28,163.7 -77.41,163.7 -77.54,163.7 -77.67,163.7 -77.8,163.33 -77.8,162.96 -77.8,162.59 -77.8,162.22 -77.8,161.85 -77.8,161.48 -77.8,161.11 -77.8,160.74 -77.8,160.37 -77.8,160 -77.8,160 -77.67,160 -77.54,160 -77.41,160 -77.28,160 -77.15,160 -77.02,160 -76.89,160 -76.76,160 -76.63,160 -76.5))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 09 May 2019 00:00:00 GMT", "description": "Cryptoendoliths are organisms that colonize microscopic cavities of rocks, which give them protection and allow them to inhabit extreme environments, such as the cold, arid desert of the Dry Valleys of Antarctica. Fossilized cryptoendoliths preserve the forms and features of organisms from the past and thus provide a unique opportunity to study the organisms\u0027 life histories and environments. To study this fossil record, there needs to be a better understanding of what environmental conditions allow these fossils to form. A climate gradient currently exists in the Dry Valleys that allows us to study living, dead, and fossilized cryptoendoliths from mild to increasingly harsh environments; providing insight to the limits of life and how these fossils are formed. This project will develop instruments to detect the biological activity of the live microorganisms and conduct laboratory experiments to determine the environmental limits of their survival. The project also will characterize the chemical and structural features of the living, dead, and fossilized cryptoendoliths to understand how they become fossilized. Knowing how microorganisms are preserved as fossils in cold and dry environments like Antarctica can help to refine methods that can be used to search for and identify evidence for extraterrestrial life in similar habitats on planets such as Mars. This project includes training of graduate and undergraduate students.\r\n\r\nLittle is known about cryptoendolithic microfossils and their formation processes in cold, arid terrestrial habitats of the Dry Valleys of Antarctica, where a legacy of activity is discernible in the form of biosignatures including inorganic materials and microbial fossils that preserve and indicate traces of past biological activity. The overarching goals of the proposed work are: (1) to determine how rates of microbial respiration and biodegradation of organic matter control microbial fossilization; and (2) to characterize microbial fossils and their living counterparts to elucidate mechanisms for fossilization. Using samples collected across an increasingly harsher (more cold and dry) climatic gradient that encompasses living, dead, and fossilized cryptoendolithic microorganisms, the proposed work will: (1) develop an instrument to be used in the field that can measure small concentrations of CO2 in cryptoendolithic habitats in situ; (2) use microscopy techniques to characterize endolithic microorganisms as well as the chemical and morphological characteristics of biosignatures and microbial fossils. A metagenomic survey of microbial communities in these samples will be used to characterize differences in diversity, identify if specific microorganisms (e.g. prokaryotes, eukaryotes) are more capable of surviving under these harsh climatic conditions, and to corroborate microscopic observations of the viability states of these microorganisms.", "east": 163.7, "geometry": "POINT(161.85 -77.15)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Antarctica; USAP-DC; NOT APPLICABLE; TERRESTRIAL ECOSYSTEMS", "locations": "Antarctica", "north": -76.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Omelon, Christopher; Breecker, Daniel; Bennett, Philip", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -77.8, "title": "Activity, Preservation and Fossilization of Cryptoendolithic Microorganisms in Antarctica", "uid": "p0010028", "west": 160.0}, {"awards": "1341669 DeMaster, David", "bounds_geometry": "POLYGON((-70 -62,-68.8 -62,-67.6 -62,-66.4 -62,-65.2 -62,-64 -62,-62.8 -62,-61.6 -62,-60.4 -62,-59.2 -62,-58 -62,-58 -62.6,-58 -63.2,-58 -63.8,-58 -64.4,-58 -65,-58 -65.6,-58 -66.2,-58 -66.8,-58 -67.4,-58 -68,-59.2 -68,-60.4 -68,-61.6 -68,-62.8 -68,-64 -68,-65.2 -68,-66.4 -68,-67.6 -68,-68.8 -68,-70 -68,-70 -67.4,-70 -66.8,-70 -66.2,-70 -65.6,-70 -65,-70 -64.4,-70 -63.8,-70 -63.2,-70 -62.6,-70 -62))", "dataset_titles": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data; Expedition Data of NBP1203; Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf; Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf; Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "datasets": [{"dataset_uid": "001438", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1203", "url": "https://www.rvdata.us/search/cruise/NBP1203"}, {"dataset_uid": "601336", "doi": "10.15784/601336", "keywords": "Antarctica; Carbon-14; Cryosphere; Larsen Ice Shelf; Lead-210; Marine Sediments; Radioisotope Analysis", "people": "Taylor, Richard; DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Radioisotope data (C-14 and Pb-210) from bulk sediments, Larsen A Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/601336"}, {"dataset_uid": "601304", "doi": null, "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Box Corer; Cryosphere; LARISSA; Larsen Ice Shelf; Macrofauna; Megafauna; NBP1203; Oceans; R/V Nathaniel B. Palmer; Seafloor Sampling; Species Abundance", "people": "Smith, Craig", "repository": "USAP-DC", "science_program": "LARISSA", "title": "Species Abundance Data from the Larsen Ice Shelf Ice acquired during R/V Nathaniel B. Palmer expedition NBP1203", "url": "https://www.usap-dc.org/view/dataset/601304"}, {"dataset_uid": "601319", "doi": "10.15784/601319", "keywords": "Antarctica; Antarctic Peninsula; Biology; Biosphere; Bioturbation Coefficients; Diagenesis; Labile Organic Carbon (LOC); LOC Mean Residence Times; Marguerite Bay; Oceans; Organic Carbon Degradation Rates; Sediment Core", "people": "DeMaster, David; Thomas, Carrie; Isla, Enrique; Smith, Craig; Taylor, Richard", "repository": "USAP-DC", "science_program": null, "title": "Labile Organic Carbon distributions on the West Antarctic Peninsula Shelf", "url": "https://www.usap-dc.org/view/dataset/601319"}, {"dataset_uid": "601082", "doi": "10.15784/601082", "keywords": null, "people": "DeMaster, David", "repository": "USAP-DC", "science_program": "LARISSA", "title": "DeMaster Compiled Larsen Ice Shelf and the West Antarctic Peninsula C14 Data", "url": "https://www.usap-dc.org/view/dataset/601082"}], "date_created": "Sat, 03 Feb 2018 00:00:00 GMT", "description": "The PI requests support to analyze sediments from multi-cores and mega-cores previously collected from beneath the former Larsen B and Larsen A ice shelves. These unique cores will allow the PI to develop a time-integrated understanding of the benthic response to ice shelf collapse off the East Antarctic Peninsula over time periods as short as 5 years following ice shelf collapse up to \u003e170 years after collapse. High latitudes are responding to climate change more rapidly than the rest of the planet and the disappearance of ice shelves are a key manifestation of climate warming. The PI will investigate the newly created benthic environments and associated ecosystems that have resulted from the re-initiation of fresh planktonic material to the sediment-water interface. This proposal will use a new geochemical technique, based on naturally occurring 14C that can be used to assess the distribution and inventory of recently produced organic carbon accumulating in the sediments beneath the former Larsen A and B ice shelves. The PI will couple 14C measurements with 210Pb analyses to assess turnover times for sedimentary labile organic matter. By comparing the distributions and inventories of labile organic matter as well as the bioturbation intensities among different locations as a function of time following ice shelf collapse/retreat, the nature and timing of the benthic response to ice shelf collapse can be assessed.", "east": -58.0, "geometry": "POINT(-64 -65)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "USAP-DC; R/V NBP; Pb-210; Species Abundance; Labile Organic Carbon; C-14; LABORATORY; NBP1203; USAP-1341669; Radioisotop", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Earth Sciences", "paleo_time": null, "persons": "DeMaster, David; Smith, Craig", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "Other; USAP-DC", "science_programs": "LARISSA", "south": -68.0, "title": "Using Radiochemical Data from Collapsed Ice Shelf Sediments to Understand the Nature and Timing of the Benthic Response to High-Latitude Climate Change", "uid": "p0000382", "west": -70.0}, {"awards": "1103428 Thurber, Andrew", "bounds_geometry": "POLYGON((165 -77,165.5 -77,166 -77,166.5 -77,167 -77,167.5 -77,168 -77,168.5 -77,169 -77,169.5 -77,170 -77,170 -77.1,170 -77.2,170 -77.3,170 -77.4,170 -77.5,170 -77.6,170 -77.7,170 -77.8,170 -77.9,170 -78,169.5 -78,169 -78,168.5 -78,168 -78,167.5 -78,167 -78,166.5 -78,166 -78,165.5 -78,165 -78,165 -77.9,165 -77.8,165 -77.7,165 -77.6,165 -77.5,165 -77.4,165 -77.3,165 -77.2,165 -77.1,165 -77))", "dataset_titles": "McMurdo Spiophanes beds 16s V4 region community composition from sediment cores at McMurdo Station, Antarctia on Sept 9th, 2012 (McMurdo Benthos project); Stable isotopic composition of McMurdo Benthos", "datasets": [{"dataset_uid": "000201", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Stable isotopic composition of McMurdo Benthos", "url": "https://www.bco-dmo.org/dataset/716462"}, {"dataset_uid": "000202", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "McMurdo Spiophanes beds 16s V4 region community composition from sediment cores at McMurdo Station, Antarctia on Sept 9th, 2012 (McMurdo Benthos project)", "url": "https://www.bco-dmo.org/dataset/716443"}], "date_created": "Tue, 10 Oct 2017 00:00:00 GMT", "description": "The biota of the world\u0027s seafloor is fueled by bursts of seasonal primary production. For food-limited sediment communities to persist, a balance must exist between metazoan consumption of and competition with bacteria, a balance which likely changes through the seasons. Polar marine ecosystems are ideal places to study such complex interactions due to stark seasonal shifts between heterotrophic and autotrophic communities, and temperatures that may limit microbial processing of organic matter. The research will test the following hypotheses: 1) heterotrophic bacteria compete with macrofauna for food; 2) as phytoplankton populations decline macrofauna increasingly consume microbial biomass to sustain their populations; and 3) in the absence of seasonal photosynthetic inputs, macrofaunal biodiversity will decrease unless supplied with microbially derived nutrition. Observational and empirical studies will test these hypotheses at McMurdo Station, Antarctica, where a high-abundance macro-infaunal community is adapted to this boom-and-bust cycle of productivity. The investigator will mentor undergraduates from a predominantly minority-serving institution, in the fields of invertebrate taxonomy and biogeochemistry. The general public and young scientists will be engaged through lectures at local K-12 venues and launch of an interactive website. The results will better inform scientists and managers about the effects of climate change on polar ecosystems and the mechanisms of changing productivity patterns on global biodiversity.", "east": 170.0, "geometry": "POINT(167.5 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Thurber, Andrew", "platforms": "Not provided", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -78.0, "title": "PostDoctoral Research Fellowship", "uid": "p0000416", "west": 165.0}, {"awards": "1141993 Rich, Jeremy", "bounds_geometry": "POLYGON((-60 -70,-59.3 -70,-58.6 -70,-57.9 -70,-57.2 -70,-56.5 -70,-55.8 -70,-55.1 -70,-54.4 -70,-53.7 -70,-53 -70,-53 -70.9,-53 -71.8,-53 -72.7,-53 -73.6,-53 -74.5,-53 -75.4,-53 -76.3,-53 -77.2,-53 -78.1,-53 -79,-53.7 -79,-54.4 -79,-55.1 -79,-55.8 -79,-56.5 -79,-57.2 -79,-57.9 -79,-58.6 -79,-59.3 -79,-60 -79,-60 -78.1,-60 -77.2,-60 -76.3,-60 -75.4,-60 -74.5,-60 -73.6,-60 -72.7,-60 -71.8,-60 -70.9,-60 -70))", "dataset_titles": "Seasonal Succession of Bacterial Communities in Coastal Waters of the Western Antarctic Peninsula", "datasets": [{"dataset_uid": "601032", "doi": "10.15784/601032", "keywords": "Antarctica; Antarctic Peninsula; Bacteria; Biology; Cryosphere; Genetic; Geochemistry; Palmer Station; Sample/Collection Description; Sea Water; Southern Ocean", "people": "Rich, Jeremy", "repository": "USAP-DC", "science_program": null, "title": "Seasonal Succession of Bacterial Communities in Coastal Waters of the Western Antarctic Peninsula", "url": "https://www.usap-dc.org/view/dataset/601032"}], "date_created": "Thu, 15 Jun 2017 00:00:00 GMT", "description": "The Western Antarctic Peninsula (WAP) has experienced unprecedented warming and shifts in sea ice cover over the past fifty years. How these changes impact marine microbial communities, and subsequently how these shifts in the biota may affect the carbon cycle in surface waters is unknown. This work will examine how these ecosystem-level changes affect microbial community structure and function. This research will use modern metagenomic and transcriptomic approaches to test the hypothesis that the introduction of organic matter from spring phytoplankton blooms drives turnover in microbial communities. This research will characterize patterns in bacterial and archaeal succession during the transition from the austral winter at two long-term monitoring sites: Palmer Station in the north and Rothera Station in the south. This project will also include microcosm incubations to directly assess the effects of additions of organic carbon and melted sea ice on microbial community structure and function. The results of this work will provide a broader understanding of the roles of both rare and abundant microorganisms in carbon cycling within the WAP region, and how these communities may shift in structure and function in response to climate change. Results will be widely disseminated through publications as well as through presentations at national and international meetings. The research will provide training opportunities for both graduate and undergraduate students and will enhance international collaborations with the British Antarctic Survey.", "east": -53.0, "geometry": "POINT(-56.5 -74.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -70.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Rich, Jeremy", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.0, "title": "Collaborative Research: Microbial Community Assembly in Coastal Waters of the Western Antarctic Peninsula", "uid": "p0000409", "west": -60.0}, {"awards": "1141978 Foreman, Christine", "bounds_geometry": "POLYGON((160 -76,160.1 -76,160.2 -76,160.3 -76,160.4 -76,160.5 -76,160.6 -76,160.7 -76,160.8 -76,160.9 -76,161 -76,161 -76.1,161 -76.2,161 -76.3,161 -76.4,161 -76.5,161 -76.6,161 -76.7,161 -76.8,161 -76.9,161 -77,160.9 -77,160.8 -77,160.7 -77,160.6 -77,160.5 -77,160.4 -77,160.3 -77,160.2 -77,160.1 -77,160 -77,160 -76.9,160 -76.8,160 -76.7,160 -76.6,160 -76.5,160 -76.4,160 -76.3,160 -76.2,160 -76.1,160 -76))", "dataset_titles": "FT-ICR MS Metadata; Respiration Metadata; UPLC-Q-TOF data of Cotton Glacier exometabolites", "datasets": [{"dataset_uid": "601089", "doi": "10.15784/601089", "keywords": "Antarctica; Biology; Biosphere; Exometabolites; Mass Spectrometry; Microbes; Microbiology", "people": "Foreman, Christine; Tigges, Michelle; Bothner, Brian", "repository": "USAP-DC", "science_program": null, "title": "UPLC-Q-TOF data of Cotton Glacier exometabolites", "url": "https://www.usap-dc.org/view/dataset/601089"}, {"dataset_uid": "601077", "doi": "10.15784/601077", "keywords": "Antarctica; Biology; Biosphere; Chemistry:Fluid; Cryosphere; Fluorescence spectroscopy; Mass Spectrometry", "people": "Foreman, Christine; D\u0027Andrilli, Juliana", "repository": "USAP-DC", "science_program": null, "title": "FT-ICR MS Metadata", "url": "https://www.usap-dc.org/view/dataset/601077"}, {"dataset_uid": "601076", "doi": "10.15784/601076", "keywords": "Antarctica; Biology; Biosphere; Chemistry:Fluid; Cryosphere; Fluorescence spectroscopy; Mass Spectrometry", "people": "Foreman, Christine; Smith, Heidi", "repository": "USAP-DC", "science_program": null, "title": "Respiration Metadata", "url": "https://www.usap-dc.org/view/dataset/601076"}], "date_created": "Tue, 25 Apr 2017 00:00:00 GMT", "description": "Uncovering the dynamics of dissolved organic matter (DOM) is central to an understanding of the global carbon cycle, as organic material from lakes, streams, oceans and soils passes through this pool. DOM acts as a key energy source for microbes in many ecosystems and therefore can affect regional nutrient cycling patterns. For example, preliminary results suggest that organisms isolated from a supraglacial stream on Cotton Glacier, Antarctica, may be important in DOM cycling in this relatively simple, low temperature system. However, little is known about the functional attributes of the microbes that interact with DOM in the environment. This project will use state-of-the-art genomics, proteomics and metabolomics approaches to understand the mechanisms by which two microbial isolates, CG3 and CG9_1, affect DOM cycling. Liquid chromatography-mass spectrometry will also be used to better characterize the microbially-derived DOM from this ecosystem. This project will support the research and training of one undergraduate and two graduate students. Results will be widely disseminated through publications as well as through presentations at national and international meetings. In addition, raw data will be made available through open-access databases. Understanding the relationship between cold-adapted microbial metabolisms and DOM pools is important as more than 90% of the Earth?s oceans are below 5 degrees Celsius.", "east": 161.0, "geometry": "POINT(160.5 -76.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Foreman, Christine; Bothner, Brian", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.0, "title": "Multidimensional \"omics\" characterization of microbial metabolism and dissolved organic matter in Antarctica", "uid": "p0000408", "west": 160.0}, {"awards": "1142117 Hansell, Dennis; 1142065 DiTullio, Giacomo; 1142044 Dunbar, Robert; 1142097 Bochdansky, Alexander", "bounds_geometry": "POLYGON((165 -52,166 -52,167 -52,168 -52,169 -52,170 -52,171 -52,172 -52,173 -52,174 -52,175 -52,175 -54.65,175 -57.3,175 -59.95,175 -62.6,175 -65.25,175 -67.9,175 -70.55,175 -73.2,175 -75.85,175 -78.5,174 -78.5,173 -78.5,172 -78.5,171 -78.5,170 -78.5,169 -78.5,168 -78.5,167 -78.5,166 -78.5,165 -78.5,165 -75.85,165 -73.2,165 -70.55,165 -67.9,165 -65.25,165 -62.6,165 -59.95,165 -57.3,165 -54.650000000000006,165 -52))", "dataset_titles": "Carbon chemistry from CTD; Deployment: NBP1302; NBP1302 data; Video Particle Profiler (VPP) and Digital Inline Holographic Microscopy (DIHM) data from cruise NBP1302", "datasets": [{"dataset_uid": "000221", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Deployment: NBP1302", "url": "http://www.bco-dmo.org/deployment/547873"}, {"dataset_uid": "600388", "doi": "10.15784/600388", "keywords": "Antarctica; Biology; Cryosphere; Holographic Microscopy; Oceans; Photo/Video; Phytoplankton; Ross Sea; Sample/Collection Description; Southern Ocean; Video Particle Profiler", "people": "Bochdansky, Alexander", "repository": "USAP-DC", "science_program": null, "title": "Video Particle Profiler (VPP) and Digital Inline Holographic Microscopy (DIHM) data from cruise NBP1302", "url": "https://www.usap-dc.org/view/dataset/600388"}, {"dataset_uid": "000179", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1302 data", "url": "https://www.rvdata.us/search/cruise/NBP1302"}, {"dataset_uid": "000220", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Carbon chemistry from CTD", "url": "http://www.bco-dmo.org/dataset/658394"}], "date_created": "Wed, 26 Aug 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eSinking particles are a major element of the biological pump and they are commonly assigned to two fates: mineralization in the water column and accumulation at the seafloor. However, there is another fate of export hidden within the vertical decline of carbon, the transformation of sinking organic matter to fine suspended and/or dissolved organic fractions. This process has been suggested but has rarely been observed or quantified. As a result, it is presumed that the solubilized fraction is largely mineralized over short time scales. However, global ocean surveys of dissolved organic carbon are demonstrating a significant water column accumulation of organic matter under high productivity environments. This proposal will investigate the transformation of organic particles from sinking to solubilized phases of the export flux in the Ross Sea. The Ross Sea experiences high export particle production, low dissolved organic carbon export with overturning circulation, and the area has a predictable succession of production and export events. In addition, the basin is shallow (\u003c 000 m) so the products the PIs will target are relatively concentrated. To address the proposed hypothesis, the PIs will use both well-established and novel biochemical and optical measures of export production and its fate. The outcomes of this work will help researchers close the carbon budget in the Ross Sea.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis research will support graduate and undergraduate students and will provide undergraduates and pre-college students with field-based research experience. Scientifically, this research will increase understanding of carbon sinks in the Ross Sea and will help develop new tools for identifying, quantifying, and tracking that carbon. The PIs will interface with K-12 students through daily reports from the field and through educational modules developed by several of the PIs in collaboration with science education specialists and college students. A K-12 educator will be included on the research cruises. Outreach will be through COSEE Florida and the Maritime Center in Norfolk, VA.", "east": 175.0, "geometry": "POINT(170 -65.25)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e DIHM; 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 PROFILERS/SOUNDERS \u003e PROFILERS; 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": "Not provided; NBP1302; R/V NBP; Phaeocystis", "locations": null, "north": -52.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Bochdansky, Alexander; Dunbar, Robert; DiTullio, Giacomo; Ditullio, Giacomo; Harry, Dennis L.; HANSELL, DENNIS", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP; Not provided", "repo": "BCO-DMO", "repositories": "BCO-DMO; Other; USAP-DC", "science_programs": null, "south": -78.5, "title": "Collaborative research: TRacing the fate of Algal Carbon Export in the Ross Sea (TRACERS)", "uid": "p0000307", "west": 165.0}, {"awards": "1141275 Warren, Stephen", "bounds_geometry": null, "dataset_titles": "Antarctic field campaign data page", "datasets": [{"dataset_uid": "001399", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Antarctic field campaign data page", "url": "http://www.atmos.washington.edu/articles/EastAntarctica_SeaIceAlbedos_SnowImpurities/"}], "date_created": "Fri, 30 Jan 2015 00:00:00 GMT", "description": "The albedo, or reflection coefficient, is a measure of the diffuse reflectivity of an irradiated surface. With the sunlit atmosphere as a light source, and sea-ice as a diffuse reflecting surface, the albedo would be the fraction of incident light that is returned to the atmosphere. A perfect (white) reflecting surface would have an albedo of 1; a perfect (black) absorbing surface would have an albedo of 0. The albedo of sea-ice is needed to assess the solar energy budget of the marginal ice zone, to compute the partial solar bands in radiation budgets in general circulation and earth system models, and is also needed to interpret remote sensing imagery data products.\u003cbr/\u003eApplications requiring albedos further into the near IR, out to 2500nm, are assumed or approximated. Modern spectral radiometers, such as will be used in this campaign on a Southern Ocean voyage from Hobart to Antarctica, can extend these measurements of albedo from 350 to 2500nm, allowing earlier estimates to be verified, or corrected. \u003cbr/\u003e\u003cbr/\u003eSurfaces to be encountered on this research cruise are expected to include open water, grease ice, nila ice, pancake ice, young grey ice, young grey-white ice, along with first year ice. The presence of variable amounts of snow on these surfaces is also of interest. Light absorbing impurities in the snow and ice, including black carbon and organic matter (brown carbon) are different from those found in Arctic Sea ice, the Antarctic being so remote from combustion sources. This may allow better understanding of the seasonal cycles, energy budgets and their recent trends in spatial extent and thickness. The project will also broaden the educational experiences of both US and Australian students participating in the measurement campaign", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "reflecting surface; LABORATORY; Sea Ice; Antarctica; Snow Temperature; albedo; Snow Density; impurities; energy budgets; COMPUTERS; radiometers; R/V AA; spectral; radiation budgets", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Warren, Stephen; Zatko, Maria", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V AA", "repo": "PI website", "repositories": "Other", "science_programs": null, "south": null, "title": "Spectral and Broadband Albedo of Antarctic Sea-ice Types", "uid": "p0000375", "west": null}, {"awards": "0838970 Foreman, Christine", "bounds_geometry": "POINT(161.667 -77.117)", "dataset_titles": "The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica", "datasets": [{"dataset_uid": "600104", "doi": "10.15784/600104", "keywords": "Antarctica; Biology; Biosphere; Cryosphere; Glaciers/Ice Sheet; Glaciology; Microbiology", "people": "Foreman, Christine", "repository": "USAP-DC", "science_program": null, "title": "The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600104"}], "date_created": "Fri, 10 Oct 2014 00:00:00 GMT", "description": "Dissolved organic matter (DOM) comprises a significant pool of Earth\u0027s organic carbon that dwarfs the amount present in living aquatic organisms. The properties and reactivity of DOM are not well defined, and the evolution of autochthonous DOM from its precursor materials in freshwater has not been observed. Recent sampling of a supraglacial stream formed on the Cotton Glacier in the Transantarctic Mountains revealed DOM that more closely resembles an assemblage of recognizable precursor organic compounds, based upon its UV-VIS and fluorescence spectra. It is suggested that the DOM from this water evolved over time to resemble materials present in marine and many inland surface waters. The transient nature of the system i.e., it reforms seasonally, also prevents any accumulation of the refractory DOM present in most surface waters. Thus, the Cotton Glacier provides us with a unique environment to study the formation of DOM from precursor materials. An interdisciplinary team will study the biogeochemistry of this progenitor DOM and how microbes modify it. By focusing on the chemical composition of the DOM as it shifts from precursor material to the more humified fractions, the investigators will relate this transition to bioavailability, enzymatic activity, community composition and microbial growth efficiency. This project will support education at all levels, K-12, high school, undergraduate, graduate and post-doc and will increase participation by under-represented groups in science. Towards these goals, the investigators have established relationships with girls\u0027 schools and Native American programs. Additional outreach will be carried out in coordination with PolarTREC, PolarPalooza, and if possible, an Antarctic Artist and Writer.", "east": 161.667, "geometry": "POINT(161.667 -77.117)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.117, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Foreman, Christine", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.117, "title": "Collaborative Research: The Biogeochemical Evolution of Dissolved Organic Matter in a Fluvial System on the Cotton Glacier, Antarctica", "uid": "p0000458", "west": 161.667}, {"awards": "0838830 Cottrell, Matthew", "bounds_geometry": "POLYGON((-64.079666 -64.77966,-64.07576590000001 -64.77966,-64.0718658 -64.77966,-64.0679657 -64.77966,-64.0640656 -64.77966,-64.06016550000001 -64.77966,-64.0562654 -64.77966,-64.0523653 -64.77966,-64.04846520000001 -64.77966,-64.0445651 -64.77966,-64.040665 -64.77966,-64.040665 -64.78326100000001,-64.040665 -64.786862,-64.040665 -64.790463,-64.040665 -64.794064,-64.040665 -64.797665,-64.040665 -64.801266,-64.040665 -64.804867,-64.040665 -64.808468,-64.040665 -64.812069,-64.040665 -64.81567,-64.0445651 -64.81567,-64.04846520000001 -64.81567,-64.0523653 -64.81567,-64.0562654 -64.81567,-64.06016550000001 -64.81567,-64.0640656 -64.81567,-64.0679657 -64.81567,-64.0718658 -64.81567,-64.07576590000001 -64.81567,-64.079666 -64.81567,-64.079666 -64.812069,-64.079666 -64.808468,-64.079666 -64.804867,-64.079666 -64.801266,-64.079666 -64.797665,-64.079666 -64.794064,-64.079666 -64.790463,-64.079666 -64.786862,-64.079666 -64.78326100000001,-64.079666 -64.77966))", "dataset_titles": "Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem", "datasets": [{"dataset_uid": "600097", "doi": "10.15784/600097", "keywords": "Antarctic Peninsula; Biology; Biosphere; LTER Palmer Station; Microbiology; Oceans; Southern Ocean", "people": "Kirchman, David; Cottrell, Matthew", "repository": "USAP-DC", "science_program": null, "title": "Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem", "url": "https://www.usap-dc.org/view/dataset/600097"}], "date_created": "Mon, 16 Dec 2013 00:00:00 GMT", "description": "This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\u003cbr/\u003e\u003cbr/\u003eLight quality and availability are likely to change in polar ecosystems as ice coverage and thickness decrease. How microbes adjust to these and other changes will have huge impacts on the polar marine ecosystems. Little is known about photoheterotrophic prokaryotes, which are hypothesized to gain a metabolic advantage by harvesting light energy in addition to utilizing dissolved organic matter (DOM). Photoheterotrophy is not included in current models of carbon cycling and energy flow. This research will examine three questions: 1. Are photoheterotrophic microbes present and active in Antarctic waters in winter and summer? 2. Does community structure of photoheterotrophs shift between summer and winter? 3. Which microbial groups assimilate more DOM in light than in the dark? The research will test hypotheses about activity of photoheterotrophs in winter and in summer, shifts in community structure between light and dark seasons and the potentially unique impacts of photoheterotrophs on biogeochemical processes in the Antarctic. The project will directly support a graduate student, will positively impact the NSF REU program at the College of Marine and Earth Studies, and will include students from the nation?s oldest historical minority college. The results will be featured during weekly tours of Lewes facilities (about 1000 visitors per year) and during Coast Day, an annual open-house that attracts about 10,000 visitors.", "east": -64.040665, "geometry": "POINT(-64.0601655 -64.797665)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -64.77966, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Cottrell, Matthew; David, Kirchman", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.81567, "title": "Photoheterotrophic Microbes in the West Antarctic Peninsula Marine Ecosystem", "uid": "p0000473", "west": -64.079666}, {"awards": "1039365 Rimmer, Susan", "bounds_geometry": null, "dataset_titles": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "datasets": [{"dataset_uid": "600121", "doi": "10.15784/600121", "keywords": "Antarctica; Chemistry:Rock; Geochemistry; Solid Earth; Transantarctic Mountains", "people": "Rimmer, Susan", "repository": "USAP-DC", "science_program": null, "title": "The Permian-Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuations in Terrestrial Organic Matter", "url": "https://www.usap-dc.org/view/dataset/600121"}], "date_created": "Wed, 30 Jan 2013 00:00:00 GMT", "description": "This project studies the Permian-Triassic extinction event as recorded in sedimentary rocks from the Transantarctic Mountains of Antarctica. Two hundred and fifty million years ago most life on Earth was wiped out in a geologic instant. The cause is a subject of great debate. Researchers have identified a unique stratigraphic section near Shackleton glacier laid down during the extinction event. Organic matter from these deposits will be analyzed by density gradient centrifugation (DGC), which will offer detailed information on the carbon isotope composition. The age of these layers will be precisely dated by U/Pb-zircon-dating of intercalated volcanics. Combined, these results will offer detailed constraints on the timing and duration of carbon isotope excursions during the extinction, and offer insight into the coupling of marine and terrestrial carbon cycles. \u003cbr/\u003eThe broader impacts of this project include graduate and undergraduate student research, K12 outreach and teacher involvement, and societal relevance of the results, since the P/T extinction may have been caused by phenomena such as methane release, which could accompany global warming.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Rimmer, Susan", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: The Permian -Triassic Transition in Antarctica: Evaluating the Rates and Variability of Carbon Isotope Fluctuatios in Terrestrial Organic Matter", "uid": "p0000507", "west": null}, {"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 cores; Not provided; LABORATORY; sulfur; Mass Spectrometry; COMPUTERS; isotopes; molecular; Nitrogen; organic matter", "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": "0230497 Kiene, Ronald", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of NBP0409", "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"}, {"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"}], "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": "Other", "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": "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": "Other", "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": "0838866 Buesseler, Ken", "bounds_geometry": "POLYGON((-75 -62,-74 -62,-73 -62,-72 -62,-71 -62,-70 -62,-69 -62,-68 -62,-67 -62,-66 -62,-65 -62,-65 -62.8,-65 -63.6,-65 -64.4,-65 -65.2,-65 -66,-65 -66.8,-65 -67.6,-65 -68.4,-65 -69.2,-65 -70,-66 -70,-67 -70,-68 -70,-69 -70,-70 -70,-71 -70,-72 -70,-73 -70,-74 -70,-75 -70,-75 -69.2,-75 -68.4,-75 -67.6,-75 -66.8,-75 -66,-75 -65.2,-75 -64.4,-75 -63.6,-75 -62.8,-75 -62))", "dataset_titles": "data deposited with Palmer Long-Term Ecological Research (LTER) repository.", "datasets": [{"dataset_uid": "000215", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "data deposited with Palmer Long-Term Ecological Research (LTER) repository.", "url": "http://pal.lternet.edu/data/"}], "date_created": "Wed, 31 Aug 2011 00:00:00 GMT", "description": "Abstract\u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eBy using a tool-box of particle flux and characterization techniques appropriate to the study of particulate organic carbon fluxes out of the upper sunlit zone, WHOI researchers will attempt to evaluate the so called \u0027biological pump\u0027 term at the Palmer Long Term Ecological Research (PAL) site in the Western Antarctic Peninsula (WAP). The goal of these measurements is to describe the seasonal dynamics of production, export (sinking) and at-depth remineralization rates of organic matter produced in the Antarctic photic zone. This should lead to a better understanding of the biogeochemical controls on the carbon cycle in this difficult to access region. Additionally, how much of the newly fixed organic carbon is exported off the shelf, effectively driving an influx of atmospheric (including anthropogenic) CO2 to be sequestered into the deep ocean is not presently known. Comparison of prior time series sediment traps in the WAP seem to indicate smaller sinking C fluxes than other, as equally as productive Antarctic coastal regions, e.g. the Ross Sea. New observations and modeling activities will attempt to explain this discrepancy, and to account for the apparently inefficient particle export. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003e\"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).\"", "east": -65.0, "geometry": "POINT(-70 -66)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -62.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Buesseler, Ken; Valdes, James", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER", "science_programs": "LTER", "south": -70.0, "title": "WAPflux - New Tools to Study the Fate of Phytoplankton Production in the West Antarctic Peninsula", "uid": "p0000686", "west": -75.0}, {"awards": "9726186 Pilskaln, Cynthia", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0101", "datasets": [{"dataset_uid": "002641", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0101", "url": "https://www.rvdata.us/search/cruise/NBP0101"}, {"dataset_uid": "002580", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0101", "url": "https://www.rvdata.us/search/cruise/NBP0101"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "This proposed work is a study of the biological production and export flux of biogenic matter in response to ventilation of intermediate and deep water masses within the Polar Front zone. It is a collaborative work between the University of Maine and the Chinese Antarctic Research Expedition (CHINARE). The shipboard work is proposed for the Chinese antarctic resupply vessel off Prydz Bay in the Indian Ocean sector. In the austral Spring, this region experiences phytoplankton blooms that are thought to be the result of nutrient transport by the ventilation of intermediate and deep water masses. On an annual basis, it is believed that such blooms are the primary source of particulate organic carbon and biogenic silica flux to the ocean bottom. At this time however no data exists on the amount of particulate organic matter that sinks through the water column, leaving the quantitative relationships between production and export largely undefined in this region. The initial phase of the work consists of setting out a time-series sediment trap mooring at approximately 64 deg S latitude and 73 deg E longitude to take advantage of the historical data set that CHINARE has obtained in this area over the past decade. The biweekly to monthly trap samples will be analyzed for their organic constituents, and in conjunction with primary productivity observations will provide the basic data from which export values can be derived. This work will be carried out in collaboration with the State Oceanic Administration of the People\u0027s Republic of China, and the Chinese Antarctic Research Expedition. In addition to providing time on the antarctic resupply vessel, the SOA will sponsor the shipboard primary productivity experiments and the supporting hydrographic measurements. The collaborating American scientists will provide guidance in making these observations to standards developed for the Joint Global Ocean Flux Study, and provide the hardware for the moored sediment trap. There will be a mutual sharing between the U.S. and Chinese investigators of all samples and data sets, and the data analysis will be carried out jointly. ***", "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 Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Leventer, Amy", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "Other", "science_programs": null, "south": null, "title": "POC Production and Export in the Indian Ocean Sector of the Southern Ocean: A US-China Collaborative Research Program", "uid": "p0000800", "west": null}, {"awards": "9527255 Mopper, Kenneth", "bounds_geometry": null, "dataset_titles": "Expedition data of LMG9809", "datasets": [{"dataset_uid": "002719", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG9809", "url": "https://www.rvdata.us/search/cruise/LMG9809"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "ACT K. Mopper \u0026 D. Kieber OPP 9527255 \u0026 OPP 9527314 PHOTOCHEMICAL AND OPTICAL PROPERTIES OF ANTARCTIC WATERS IN RESPONSE TO CHANGING UV-B FLUXES The decrease in stratospheric ozone over the Antarctic results in an increase in the UV-B flux in the euphotic zone. The increase leads to cellular damage to aquatic organisms, as documented by photo-inhibition and decreased productivity. Cellular damage can occur either intracellularly, or externally at the cell surface from biomolecular reactions with externally-generated reactive transients. The extent of this extracellular damage will depend on the photochemistry of the seawater surrounding the cell. Until recently, nothing was known about the type of photochemical processes, rates, and steady state concentrations of transients in Antarctic waters. It is proposed that field experiments be performed which will allow the construction of predictive models of photochemical production rates in surface waters and with depth. These studies will involve further quantum yield measurementts, development of a sensitive underwater actinometer system, and use of a new underwater multichannel photometer. The model will allow the prediction of the impact of varying levels of UV-B on the photoproduction and steady state concentration of several key reactive transient species in the upper water column. In addition to this effort, experiments will also be performed to study the photodegradation of dissolved organic matter and to determine whether biologically utilizable substrates that are formed photochemically can enhance secondary productivity in Antarctic waters.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Mopper, Kenneth", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "Other", "science_programs": null, "south": null, "title": "Collaborative Research: Photochemical and Optical Properties of Antarctic Waters in Response to Changing UV-B Fluxes", "uid": "p0000870", "west": null}, {"awards": "9221598 Mopper, Kenneth", "bounds_geometry": null, "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002282", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9306"}], "date_created": "Fri, 19 Jun 2009 00:00:00 GMT", "description": "Decreases in stratospheric ozone over the Antarctic result in an increase in the ultraviolet radiation flux in the euphotic zone of the ocean. This increase may lead to cellular damage in aquatic organisms resulting in photo-inhibition and decreased productivity. Cellular damage can occur either intracellularly, or externally at the cell surface from biomolecular reactions with externally-generated reactive transient species. Extracellular damage will depend to a large degree on the photochemistry of the seawater surrounding the cell. To date, little is known about the photochemistry of the unique Antarctic waters. This project integrates a field and laboratory approach to obtain baseline information regarding the marine photochemistry of the euphotic zone in Antarctica waters as related to changes in ultraviolet radiation levels. In situ photochemical production rates and steady state concentrations of a suite of reactive species and dissolved organic matter degradation products as well as downwelling ultraviolet radiation will be measured. Additionally, flux by in situ chemical actinometry, action spectra for photochemical production of various reactive species and dissolved organic matter degradation products, and fluorescence and absorbance properties of dissolved organic matter will be determined. This information will serve as a basis for understanding and predicting the effects of ultraviolet radiation-induced marine photochemical processes on the productivity and ecology in the euphotic zone of the Antarctic Ocean.", "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": "Mopper, Kenneth; Neale, Patrick", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "Other", "science_programs": null, "south": null, "title": "Photochemistry of Antarctic Waters in Repsonse to Changing Ultraviolet Radiation Fluxes", "uid": "p0000649", "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": "Biology; Biosphere; McMurdo Sound; Oceans; Phytoplankton; Ross Sea; Southern Ocean; Zooplankton", "people": "Smith, Walker; Tang, Kam", "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": "0338342 Foreman, Christine; 0338260 Chin, Yu-Ping", "bounds_geometry": "POINT(166.167 -77.55)", "dataset_titles": "Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "datasets": [{"dataset_uid": "600168", "doi": "10.15784/600168", "keywords": "Antarctica; Chemistry:Fluid; Critical Zone; Cryosphere; Ross Island; Sample/Collection Description; Water Samples", "people": "Chin, Yu-Ping; Foreman, Christine", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "url": "https://www.usap-dc.org/view/dataset/600168"}], "date_created": "Mon, 16 Mar 2009 00:00:00 GMT", "description": "Dissolved organic matter (DOM) is a significant chemical component in aquatic systems because it acts as an important carbon source for microorganisms, absorbs harmful radiation in sunlight, is able to complex metals, and can participate in important biogeochemical reactions. This study will investigate the biogeochemical cycling of DOM in a small coastal Antarctic pond, Pony Lake, located on Cape Royds, Ross Island. Because there are no higher plants present at this site all of the DOM in this lake is derived from microorganisms. Thus, Pony Lake is an ideal site to study the effect of physical, chemical, and microbial processes on the composition and character of the DOM pool. Finally, Pony Lake is also an ideal site to collect an International Humic Substances Society (IHSS) fulvic acid standard. Unlike other IHSS standards, this standard will not contain DOM components derived from higher land plants. To better understand the role of physical influences, the project will study the changes in the DOM pool as the lake evolves from ice-covered to ice-free conditions during the summer, as well as the relationship of DOM to the observed turnover of dominant microbial communities in the lake. Scientists will also monitor changes in microbial abundance, diversity, and productivity that may occur during the ice to open-water transition period. This research will provide much needed information regarding the relationship between microbial diversity and DOM biogeochemistry. Middle school science students will be active participants in this project through the Internet, while scientists are in the field, and in the lab.", "east": 166.167, "geometry": "POINT(166.167 -77.55)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided; FIELD SURVEYS", "locations": null, "north": -77.55, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Foreman, Christine; Chin, Yu-Ping", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.55, "title": "Collaborative Research: Biogeochemistry of Dissolved Organic Matter in Pony Lake, Ross Island", "uid": "p0000548", "west": 166.167}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}]

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