[{"awards": "2326960 Doddi, Abhiram", "bounds_geometry": "POLYGON((36 -68,36.9 -68,37.8 -68,38.7 -68,39.6 -68,40.5 -68,41.4 -68,42.3 -68,43.2 -68,44.1 -68,45 -68,45 -68.2,45 -68.4,45 -68.6,45 -68.8,45 -69,45 -69.2,45 -69.4,45 -69.6,45 -69.8,45 -70,44.1 -70,43.2 -70,42.3 -70,41.4 -70,40.5 -70,39.6 -70,38.7 -70,37.8 -70,36.9 -70,36 -70,36 -69.8,36 -69.6,36 -69.4,36 -69.2,36 -69,36 -68.8,36 -68.6,36 -68.4,36 -68.2,36 -68))", "dataset_titles": null, "datasets": null, "date_created": "Sat, 20 May 2023 00:00:00 GMT", "description": "This is an international collaboration between the University of Colorado, the University of Kyoto, and the National Institute of Polar Research (NIPR) in Tokyo, to carry out a 40-day observational field campaign as part of the Japanese Antarctic Research Expedition (JARE) to Syowa station (690S, 400E) located on the eastern Antarctic coast. This campaign will deploy 44 custom high-altitude in-situ instruments called HYFLITS (\u0027Hypersonic Flight in the Turbulent Stratosphere\u0027) to characterize turbulence in the troposphere and lower stratosphere, as well as conduct intercomparisons with the VHF PANSY radar (\u2018Program of the ANtarctic SYowa\u2019) observations and concurrently deployed LODEWAVE (LOng-Duration balloon Experiment of gravity WAVE over Antarctica) observations.\r\nThis research is motivated by the fact that the sources representing realistic multi-scale gravity wave (GW) drag, and Kelvin Helmholtz Instability (KHI) dynamics in enhanced shear flows, and their contributions to momentum/energy budgets due to turbulent transport/mixing, are largely missing in the current state-of-the-art General Circulation Model (GCM) parameterization schemes. This results in poor and unreliable model forecasts of flow features from local to synoptic scales at southern high latitudes. \r\nThe proposed research aims to utilize high-resolution in-situ turbulence instruments to characterize the multi-scale GW sources and breaking, KHI instabilities emerging in a wide range of scales, Reynolds and Richardson numbers, and background GW environments in the coastal Antarctic region and quantify their contributions to the momentum and turbulence energy budgets in the tropo-stratosphere. Specific research objectives include the following:\r\n1.\tCharacterize the large-scale dynamics of orographic GWs produced by katabatic forcing and non-orographic GWs produced by summer tropopause jets and low-pressure synoptic-scale events employing targeted HYFLITS and LODEWAVE measurements in conjunction with PANSY radar observations.\r\n2.\tQuantify the GW momentum fluxes using HYFLITS and LODEWAVE measurements, and the turbulence dissipation rates using HYFLITS and PANSY radar measurements for representative multi-scale GW and KHI events to assess the zonal and meridional energy and constituent transport, and the variability in turbulence intensities/mixing throughout the troposphere and lower stratosphere.\r\nThe project will deploy the low-cost HYFLITS systems equipped with custom in-situ turbulence and radiosonde instruments at Syowa station. These balloon payloads descend slowly from an apogee of 20 km to provide high-resolution, wake-free turbulence observations, with guidance from real-time PANSY radar echoes and in coordination with the LODEWAVE experiment, to profile the atmospheric states for representative dynamical events.", "east": 45.0, "geometry": "POINT(40.5 -69)", "instruments": null, "is_usap_dc": true, "keywords": "TURBULENCE; ATMOSPHERIC WINDS; VERTICAL PROFILES; ATMOSPHERIC PRESSURE; HUMIDITY; Syowa Station", "locations": "Syowa Station", "north": -68.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Doddi, Abhiram; Lawrence, Dale", "platforms": null, "repositories": null, "science_programs": null, "south": -70.0, "title": "RAPID: In-situ Observations to Characterize Multi-Scale Turbulent Atmospheric Processes Impacting Climate at Southern High Latitudes", "uid": "p0010420", "west": 36.0}, {"awards": "2135184 Arrigo, Kevin; 2135185 Resing, Joseph; 2135186 Baumberger, Tamara", "bounds_geometry": "POLYGON((155 -61,156.5 -61,158 -61,159.5 -61,161 -61,162.5 -61,164 -61,165.5 -61,167 -61,168.5 -61,170 -61,170 -61.2,170 -61.4,170 -61.6,170 -61.8,170 -62,170 -62.2,170 -62.4,170 -62.6,170 -62.8,170 -63,168.5 -63,167 -63,165.5 -63,164 -63,162.5 -63,161 -63,159.5 -63,158 -63,156.5 -63,155 -63,155 -62.8,155 -62.6,155 -62.4,155 -62.2,155 -62,155 -61.8,155 -61.6,155 -61.4,155 -61.2,155 -61))", "dataset_titles": null, "datasets": null, "date_created": "Fri, 30 Sep 2022 00:00:00 GMT", "description": "Part 1.\r\nPhytoplankton blooms throughout the world support critical marine ecosystems and help remove harmful CO2 from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either the continental margin or sea-ice. However, recent work demonstrates that hydrothermal vents may be an additional iron source for phytoplankton blooms. This enhancement of phytoplankton productivity by different iron sources supports rich marine ecosystems and leads to the sequestration of C in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton blooms along the southern boundary of the Antarctic Circumpolar Current just north of the Ross Sea. It will also lead towards a better understanding of the overall impact of hydrothermal activity on the C cycle in the Southern Ocean, which appears to trigger local hotspots of enhanced biological activity which are a potential as a sink for atmospheric CO2. This project will encourage the participation of underrepresented groups in ocean sciences, as well as providing educational opportunities for high school and undergraduate students, through three different programs. Stanford University\u2019s Summer Undergraduate Research in Geoscience and Engineering (SURGE) program provides undergraduates from different US universities and diverse cultural backgrounds the opportunity to spend a summer doing a research project at Stanford. The Stanford Earth Summer Undergraduate Research Program (SESUR) is for Stanford undergraduates who want to learn more about environmental science by performing original research. Finally, Stanford\u2019s School of Earth, Energy, and Environmental Sciences High School Internship Program enables young scientists to serve as mentors, prepares high school students for college, and serves to strengthen the partnership between Stanford and local schools. Students present their results at the Fall AGU meeting as part of the AGU Bright STaRS program. This project will form the basis of at least two Ph.D. dissertations. The Stanford student will participate in Stanford\u2019s Woods Institute Rising Environmental Leaders Program (RELP), a year-round program that helps graduate students hone their leadership and communication skills to maximize the impact of their research. The graduate student will also participate in Stanford\u2019s Grant Writing Academy where they will receive training in developing and articulating research strategies to tackle important scientific questions. \r\n\r\nPart 2.\r\nThis interdisciplinary program combines satellite and ship-based measurements of a large poorly understood phytoplankton bloom (the AAR bloom) in the northwestern Ross Sea sector of the Southern Ocean with a detailed modeling study of the physical processes linking deep dissolved iron (DFe) reservoirs to the surface phytoplankton bloom. Prior to the cruise, we will implement a numerical model (CROCO) for our study region so that we can better understand the circulation, plumes, turbulence, fronts, and eddy field around the AAR bloom and how they transport and mix hydrothermally produced DFe vertically. Post cruise, observations of the vertical distribution of 3He (combined with DMn and DFe), will be used as initial conditions for a passive tracer in the model, and tracer dispersal will be assessed to better quantify the role of the various turbulent processes in upwelling DFe-rich waters to the upper ocean. The satellite-based component of the program will characterize the broader sampling region before, during, and after our cruise. During the cruise, our automated software system at Stanford University will download and process images of sea ice concentration, Chl a concentration, sea surface temperature (SST), and SSH and send them electronically to the ship. Operationally, our goal is to use all available satellite data and preliminary model results to target shipboard sampling both geographically and temporally to optimize sampling of the AAR bloom. We will use available BGC-Argo float data to help characterize the AAR bloom. In collaboration with SOCCOM, we will deploy additional BGC-Argo floats (if available) during our transit through the study area to allow us to better characterize the bloom. The centerpiece of our program will be a 40-day process study cruise in austral summer. The cruise will consist of an initial \u201cradiator\u201d pattern of hydrographic surveys/sections along the AAR followed by CTDs to selected submarine volcanoes. When/if eddies are identified, they will be sampled either during or after the initial surveys. The radiator pattern, or parts thereof, will be repeated 2-3 times. Hydrographic survey stations will include vertical profiles of temperature, salinity, oxygen, oxidation-reduction potential, light scatter, and PAR (400-700 nm). Samples will be collected for trace metals, ligands, 3He, and total suspended matter. Where intense hydrothermal activity is identified, samples for pH and total CO2 will also be collected to characterize the hydrothermal system. Water samples will be collected for characterization of macronutrients, and phytoplankton physiology, abundance, species composition, and size. During transits, we will continuously measure atmospheric conditions, current speed and direction, and surface SST, salinity, pCO2, and fluorescence from the ship\u2019s systems to provide detailed maps of these parameters. The ship will be used as a platform for conducting phytoplankton DFe bioassay experiments at key stations throughout the study region both inside and outside the bloom. We will also perform detailed comparisons of algal taxonomic composition, physiology, and size structure inside and outside the bloom to determine the potential importance of each community on local biogeochemistry.", "east": 170.0, "geometry": "POINT(162.5 -62)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; TRACE ELEMENTS; BIOGEOCHEMICAL CYCLES; hydrothermal vent; Phytoplankton; Primary Production", "locations": "Antarctica", "north": -61.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph", "platforms": null, "repositories": null, "science_programs": null, "south": -63.0, "title": "Collaborative Research: Understanding the Massive Phytoplankton Blooms over the Australian-Antarctic Ridge", "uid": "p0010381", "west": 155.0}, {"awards": "2218996 Collins, Kristina", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": null, "datasets": null, "date_created": "Sun, 07 Aug 2022 00:00:00 GMT", "description": "Magnetic field variations on the Earth\u2019s surface can be used to remote sense and characterize electrical currents and plasma waves in the near-Earth space environment that can affect technology, for example by inducing currents in power grids. Asymmetries between the space environment in the polar regions of the northern and southern hemispheres can profoundly affect these magnetic field variations. Magnetometers, which measure the strength and direction of magnetic fields, have been installed in the Arctic and Antarctic at opposite ends of the Earth\u2019s magnetic field lines. By looking at data from both sets of magnetometers, researchers can determine whether disturbances in the Earth\u2019s magnetosphere (a region of near-Earth space dominated by the Earth\u2019s magnetic field) caused by the Sun impact the Northern hemisphere, the Southern hemisphere or both, and thus understand the sources of north-south hemisphere asymmetries. Some events that appear in the magnetometer data may be difficult for computers to identify, but easy for people to identify if the data is translated into sound. Researchers will develop a tool for listening to data in a virtual reality environment, so that data from various instruments can be played back, making it easier to explore datasets intuitively. This system will be prototyped using a mixed reality headset for use in both science and education and may be used to analyze data taken at the same time by sensors on the ground and on satellites.\r\n\r\nThis project will examine one particular type of disturbance \u2013 magnetosheath jets \u2013 and its relation to plasma waves by addressing the question \u201cDo magnetosheath jets routinely drive Pc5/Pc6 geomagnetic pulsations?\u201d via the analysis of magnetometer data from geomagnetically conjugate (based on the International Geomagnetic Reference Field, IGRF) Arctic and Antarctic magnetometers. This question will be approached first through traditional plotting and visual analysis, then by presenting datastreams as sound sources situated in a virtual audio environment developed in the Unity game engine and integrated with mixed reality presentation via the Microsoft Hololens platform. This approach will leverage human capabilities for spatial discrimination of sounds to identify geomagnetic pulsations (surface magnetic field variations related to plasma waves in outer space) related to magnetosheath jet events with potentially large north-south hemispheric asymmetries, spatially localized wave activity, and irregular waveforms. The resulting presentation modality will make use of existing repositories of magnetometer data and may potentially be extended to the presentation of synchronous datasets from multiple sensing networks.\r\n", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MAGNETIC FIELD", "locations": null, "north": -60.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": null, "persons": "Collins, Kristina", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "OPP-PRF: Conjugate Experiment to Explore Magnetospheric Phenomena Via Spatial Sonification and Mixed Reality", "uid": "p0010363", "west": -180.0}, {"awards": "1744767 Sanders, Robert", "bounds_geometry": "POLYGON((-68 -64,-67.4 -64,-66.8 -64,-66.2 -64,-65.6 -64,-65 -64,-64.4 -64,-63.8 -64,-63.2 -64,-62.6 -64,-62 -64,-62 -64.5,-62 -65,-62 -65.5,-62 -66,-62 -66.5,-62 -67,-62 -67.5,-62 -68,-62 -68.5,-62 -69,-62.6 -69,-63.2 -69,-63.8 -69,-64.4 -69,-65 -69,-65.6 -69,-66.2 -69,-66.8 -69,-67.4 -69,-68 -69,-68 -68.5,-68 -68,-68 -67.5,-68 -67,-68 -66.5,-68 -66,-68 -65.5,-68 -65,-68 -64.5,-68 -64))", "dataset_titles": "Companion datasets to Diversity of microbial eukaryotes along the West Antarctic peninsula in austral spring.; Expedition Data of NBP1910; NBP1910_protist_community_RNA Raw sequence reads", "datasets": [{"dataset_uid": "200320", "doi": "10.6084/m9.figshare.19514110.v3", "keywords": null, "people": null, "repository": "figshare", "science_program": null, "title": "Companion datasets to Diversity of microbial eukaryotes along the West Antarctic peninsula in austral spring.", "url": "https://doi.org/10.6084/m9.figshare.19514110.v3"}, {"dataset_uid": "200319", "doi": "", "keywords": null, "people": null, "repository": "NCBI", "science_program": null, "title": "NBP1910_protist_community_RNA Raw sequence reads", "url": "https://www.ncbi.nlm.nih.gov/search/all/?term=PRJNA807326"}, {"dataset_uid": "200325", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data of NBP1910", "url": "https://www.rvdata.us/search/cruise/NBP1910"}], "date_created": "Wed, 27 Jul 2022 00:00:00 GMT", "description": "Traditional models of oceanic food chains have consisted of photosynthetic algae (phytoplankton) being ingested by small animals (zooplankton), which were ingested by larger animals (fish). These traditional models changed as new methods allowed recognition of the importance of bacteria and other non-photosynthetic protozoa in more complex food webs. More recently, the wide-spread existence of mixotrophs (organisms that can both photosynthesize and ingest food particles) and their importance as microbial predators has been recognized in many oceanographic areas. In the Southern Ocean, the only two surveys of mixotrophs have suggested that there may be seasonal differences in their importance as predators. During the long polar night (winter), the ability of mixotrophs to ingest particulate food may aid in their survival thus ensuring a sufficient population in spring to support a phytoplankton bloom once photosynthesis rates can increase. Thus mixotrophs may provide a critical early food source upon which zooplankton and larger animals depend on for growth and reproduction. This project will advance understanding of mixotroph diversity and their ecological impact within the Southern Ocean microbial food web. Specifically, efforts will be focused on mixotrophy in the western Antarctica peninsula region during the austral spring and autumn when there are likely to be changes in the relative importance of photosynthesis and ingestion to mixotrophs. The project will provide research opportunities for undergraduate and graduate students and a post-doctoral researcher. There will be real-time outreach from the Southern Ocean to the public via blogs and interviews, and to high school art students through an established program that blends science and art education. Despite traditional views of protists as either \"phototrophic\" or \"heterotrophic,\" there are many photosynthetic protists that consume prey (mixotrophy). Mixotrophy is a widespread phenomenon in aquatic systems and phytoplankton groups with known mixotrophic species, notably chrysophytes, cryptophytes, prymnesiophytes, prasinophytes and dinoflagellates, are present and often abundant in Antarctic waters. However, in the Southern Ocean, the presence of mixotrophic phytoflagellates has been surveyed only twice prior to this project: in the Ross Sea during Austral spring 2008 and summer 2011. The primary goals of the project are to gain better understanding of mixotroph diversity and their ecological impact with respect to the Southern Ocean microbial food web. The contribution of mixotrophs to primary production and bacterial consumption is likely linked to the taxonomic composition of the community and the abundance of particular species. Abundances of novel mixotrophic species will be evaluated via qPCR, which will be coupled with assessments of rates of feeding and photosynthesis with the goal of describing how active mixotrophs direct the movement of carbon through food webs. These experiments will help the determination of how viable and widespread mixotrophy is as a nutritional strategy in polar waters and give direct information on the currently unknown diversity of mixotrophic taxa under different environmental conditions occurring in austral spring and autumn. Furthermore, the methods will simultaneously yield information on the whole communities of protists - mixotrophic, phototrophic and heterotrophic. In addition, a method to examine aspects of the taxonomic and functional diversities of the bacterivorous/mixotrophic community will be employed. A thymidine analog (BrdU) will be used to label DNA of eukaryotes feeding on bacteria. The BrdU-labeled eukaryotic DNA will be isolated using immunoprecipitation. High-throughput sequencing of the labeled DNA (bacterivores) versus unlabeled community DNA will determine the diversity of bacterivorous mixotrophs relative to other microeukaryotes. Flow cytometric sorting based on chlorophyll to focus on mixotrophic species. These approaches will elucidate a gap in current knowledge of the influence of microbial interactions in the Southern Ocean under different conditions. This award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -62.0, "geometry": "POINT(-65 -66.5)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctic Peninsula; PLANKTON; COASTAL", "locations": "Antarctic Peninsula", "north": -64.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Sanders, Robert; Gast, Rebecca; Jeffrey, Wade H.", "platforms": null, "repo": "figshare", "repositories": "Other", "science_programs": null, "south": -69.0, "title": "Collaborative Research: Diversity and ecological impacts of Antarctic mixotrophic phytoplankton", "uid": "p0010357", "west": -68.0}, {"awards": "1643285 Joughin, Ian; 1643174 Padman, Laurence", "bounds_geometry": "POLYGON((-104 -73,-102.2 -73,-100.4 -73,-98.6 -73,-96.8 -73,-95 -73,-93.2 -73,-91.4 -73,-89.6 -73,-87.8 -73,-86 -73,-86 -73.8,-86 -74.6,-86 -75.4,-86 -76.2,-86 -77,-86 -77.8,-86 -78.6,-86 -79.4,-86 -80.2,-86 -81,-87.8 -81,-89.6 -81,-91.4 -81,-93.2 -81,-95 -81,-96.8 -81,-98.6 -81,-100.4 -81,-102.2 -81,-104 -81,-104 -80.2,-104 -79.4,-104 -78.6,-104 -77.8,-104 -77,-104 -76.2,-104 -75.4,-104 -74.6,-104 -73.8,-104 -73))", "dataset_titles": "Beta Version of Plume Model; Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier; icepack; Pine Island Basin Scale Model", "datasets": [{"dataset_uid": "200313", "doi": "", "keywords": null, "people": null, "repository": "github", "science_program": null, "title": "Beta Version of Plume Model", "url": "https://github.com/icepack/plumes"}, {"dataset_uid": "200314", "doi": "", "keywords": null, "people": null, "repository": "github", "science_program": null, "title": "icepack", "url": "https://github.com/icepack/icepack"}, {"dataset_uid": "200290", "doi": "http://hdl.handle.net/1773/46687", "keywords": null, "people": null, "repository": "Uni. Washington ResearchWorks Archive", "science_program": null, "title": "Data associated with Ice-Shelf Retreat Drives Recent Pine Island Glacier Speedup and Ocean-Induced Melt Volume Directly Paces Ice Loss from Pine Island Glacier", "url": "https://doi.org/10.6069/2MZZ-6B61"}, {"dataset_uid": "200315", "doi": "", "keywords": null, "people": null, "repository": "github", "science_program": null, "title": "Pine Island Basin Scale Model", "url": "https://github.com/fastice/icesheetModels"}], "date_created": "Fri, 13 May 2022 00:00:00 GMT", "description": "Overview: Several recent studies indicate continuing and increasing ice loss from the Amundsen Sea region of West Antarctica (chiefly Pine Island and Thwaites glaciers). This loss is initiated by thinning of the floating ice shelves by basal melting driven by circulation of relatively warm ocean water under the ice shelves. This thinning triggers ice-dynamics related feedbacks, which leads to loss of ice from the grounded ice sheet. Models suggest that, even though long-term committed ice loss might be governed by ice dynamics, the magnitude of ocean-driven melting at the base of the ice shelves plays a critical role in controlling the rate of ice loss. These conclusions, however, are based on simple parameterized models for melt rate that do not take into account how ocean circulation will change in future as large-scale climate forcing changes, and as the ice shelves thin and retreat through both excess melting and accelerated ice flow. Given that present global climate models struggle to resolve the modern ocean state close to the ice shelves around Antarctica, their projections of future impacts on basal melting and time scale of ice loss have large uncertainties.\r\nThis project is aimed at reducing these uncertainties though two approaches: (i) assessing, for a given ocean state, how the melt rates will change as ice-shelf cavities evolve through melting and grounding-line retreat, and (ii) improving understanding of the sensitivity of melt rates beneath the Pine Island and Thwaites ice shelves to changes in ocean state on the Amundsen Sea continental shelf. These studies will provide more realistic bounds on ice loss and sea level rise, and lay the groundwork for development of future fully-coupled ice sheet-ocean simulations.\r\nIntellectual Merit: Rather than pursue a strategy of using fully coupled models, this project adopts a simpler semi-coupled approach to understand the sensitivity of ice-shelf melting to future forcing. Specifically, the project focuses on using regional ocean circulation models to understand current and future patterns of melting in ice-shelf cavities. The project\u2019s preliminary stage will focus on developing high-resolution ice-shelf cavity-circulation models driven by modern observed regional ocean state and validated with current patterns of melt inferred from satellite observations. Next, an ice-flow model will be used to estimate the future grounding line at various stages of retreat. Using these results, an iterative process with the ocean-circulation and ice-flow models will be applied to determine melt rates at each stage of grounding line retreat. These results will help assess whether more physically constrained melt-rate estimates substantially alter the hypothesis that unstable collapse of the Amundsen Sea sector of West Antarctica is underway. Further, by multiple simulations with modified open-ocean boundary conditions, this study will provide a better understanding of the sensitivity of melt to future changes in regional forcing. For example, what is the sensitivity of melt to changes in Circumpolar Deep Water temperature and to changes in the thermocline height driven be changes in wind forcing? Finally, several semi-coupled ice-ocean simulations will be used to investigate the influence of the ocean-circulation driven distribution of melt over the next several decades. These simulations will provide a much-improved understanding of the linkages between far-field ocean forcing, cavity circulation and melting, and ice-sheet response.\r\nBroader Impacts: Planning within the current large range of uncertainty in future sea level change leads to high social and economic costs for governments and businesses worldwide. Thus, our project to reduce sea-level rise uncertainty has strong societal as well as scientific interest. The findings and methods will be applicable to ice shelf cavities in other parts of Antarctica and northern Greenland, and will set the stage for future studies with fully coupled models as computational resources improve. This interdisciplinary work combines expertise of glaciologists and oceanographers, and will contribute to the education of new researchers in this field, with participation of graduate students and postdocs. Through several outreach activities, team members will help make the public aware of the dramatic changes occurring in Antarctica along with the likely consequences.\r\n\r\nThis proposal does not require fieldwork in the Antarctic.\r\n", "east": -86.0, "geometry": "POINT(-95 -77)", "instruments": null, "is_usap_dc": true, "keywords": "GLACIER MOTION/ICE SHEET MOTION; USA/NSF; ICE SHEETS; MODELS; AMD/US; AMD; USAP-DC; Pine Island Glacier", "locations": "Pine Island Glacier", "north": -73.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Integrated System Science; Antarctic Glaciology; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Joughin, Ian; Dutrieux, Pierre; Padman, Laurence; Springer, Scott", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "github", "repositories": "Other", "science_programs": null, "south": -81.0, "title": "Collaborative Research: Modeling ice-ocean interaction for the rapidly evolving ice shelf cavities of Pine Island and Thwaites glaciers, Antarctica ", "uid": "p0010318", "west": -104.0}, {"awards": "2148517 Hancock, Cathrine", "bounds_geometry": "POLYGON((-60 -55,-51 -55,-42 -55,-33 -55,-24 -55,-15 -55,-6 -55,3 -55,12 -55,21 -55,30 -55,30 -57,30 -59,30 -61,30 -63,30 -65,30 -67,30 -69,30 -71,30 -73,30 -75,21 -75,12 -75,3 -75,-6 -75,-15 -75,-24 -75,-33 -75,-42 -75,-51 -75,-60 -75,-60 -73,-60 -71,-60 -69,-60 -67,-60 -65,-60 -63,-60 -61,-60 -59,-60 -57,-60 -55))", "dataset_titles": "Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre", "datasets": [{"dataset_uid": "601652", "doi": "10.15784/601652", "keywords": "Antarctica; ANTXXIV/3; Argo Float; Artoa4Argo; Cryosphere; GPS Data; RAFOS; US Argo Program; Weddell Sea", "people": "Hancock, Cathrine", "repository": "USAP-DC", "science_program": null, "title": "Under ice trajectories for RAFOS enabled profiling floats in the Weddell Gyre", "url": "https://www.usap-dc.org/view/dataset/601652"}], "date_created": "Fri, 25 Mar 2022 00:00:00 GMT", "description": "The Weddell Gyre is one of the major components of the Southern Ocean circulation system, linking heat and carbon fluxes in the Antarctic Circumpolar Current to the continental margins. Water masses entering the Weddell Gyre are modified as they move in a great circular route around the gyre margin and change through processes involving air-sea-cryosphere interactions as well as through ocean eddies that mix properties across the gyre boundaries. Some of the denser water masses exit the gyre through pathways along the northern boundary, and ultimately ventilate the global deep ocean as Antarctic Bottom Water. While in-situ and satellite observations, as well as computer modeling efforts, provide estimates of the large-scale average flow within the gyre, details of the smaller-scale, or \"mesoscale\" eddy flow remain elusive. The proposed research will quantify mixing due to mesoscale eddies within the Weddell Gyre, as well as the transport of incoming deep water from the northeast, thought to be a result of transient eddies. Since the Weddell Gyre produces source water for about 40% of Antarctic Bottom Water formation, understanding the dynamics in this region helps to identify causes of documented changes in global bottom waters. This in turn, will give insight into how climate change is affecting global oceans, through modification of dense polar waters and Antarctic Bottom Water characteristics.\r\n\r\nThis project aims to track 153 RAFOS-enabled Argo floats in the ice-covered regions of the Weddell Gyre. The resultant tracks along with all available Argo and earlier float data will be used to calculate Eulerian and Lagrangian means and eddy statistics for the Weddell Gyre. The study will link RAFOS tracks with Argo profiles under ice, allowing one to characterize the importance of eddies in water column modification at critical ice-edge boundaries and leads. With RAFOS tracks near the northeastern limit of the gyre, the project will investigate the eddy-driven processes of incoming Circumpolar Deep Water, to understand better the mechanisms and volume fluxes involved. Previous work shows that a large fraction of the mean circulation in the southern and western limits of the gyre, where it contacts the Antarctic continent, occurs in a narrow boundary layer above the slope. The research here will integrate this flow structure into a complete interior and boundary layer mean circulation synthesis. The findings and products from the proposed work will improve the positioning of Argo profiles in the polar regions, which would allow for more accurate climatological maps and derived quantities. Estimates of meso-scale mixing may serve as a foundation for the development of new parameterization schemes employed in climate models, as well as local and global ocean circulation models in polar regions.", "east": 30.0, "geometry": "POINT(-15 -65)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; Weddell Sea; OCEAN CURRENTS; AMD; WATER MASSES; BUOYS; USA/NSF; USAP-DC", "locations": "Weddell Sea", "north": -55.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Hancock, Cathrine; Speer, Kevin", "platforms": "WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED \u003e BUOYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -75.0, "title": "Weddell Gyre Mean Circulation and Eddy Statistics from Floats", "uid": "p0010310", "west": -60.0}, {"awards": "2122248 Waters, Laura", "bounds_geometry": "POLYGON((-127.143608 -77.1380528,-127.1012394 -77.1380528,-127.0588708 -77.1380528,-127.0165022 -77.1380528,-126.9741336 -77.1380528,-126.931765 -77.1380528,-126.8893964 -77.1380528,-126.8470278 -77.1380528,-126.8046592 -77.1380528,-126.7622906 -77.1380528,-126.719922 -77.1380528,-126.719922 -77.14809141,-126.719922 -77.15813002,-126.719922 -77.16816863,-126.719922 -77.17820724,-126.719922 -77.18824585,-126.719922 -77.19828446,-126.719922 -77.20832307,-126.719922 -77.21836168,-126.719922 -77.22840029,-126.719922 -77.2384389,-126.7622906 -77.2384389,-126.8046592 -77.2384389,-126.8470278 -77.2384389,-126.8893964 -77.2384389,-126.931765 -77.2384389,-126.9741336 -77.2384389,-127.0165022 -77.2384389,-127.0588708 -77.2384389,-127.1012394 -77.2384389,-127.143608 -77.2384389,-127.143608 -77.22840029,-127.143608 -77.21836168,-127.143608 -77.20832307,-127.143608 -77.19828446,-127.143608 -77.18824585,-127.143608 -77.17820724,-127.143608 -77.16816863,-127.143608 -77.15813002,-127.143608 -77.14809141,-127.143608 -77.1380528))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 19 Aug 2021 00:00:00 GMT", "description": "Isotopic and sedimentary datasets reveal that volcanic activity typically increases during interglacial periods. However, the physical mechanisms through which changes in the surface loading affect volcanic magmatic plumbing systems remain unconstrained. Recently generated 40Ar/39Ar eruption ages indicate that 86% of the dated samples from Mt. Waesche, a late Quaternary volcano in Marie Byrd land, correlate with interglacial periods, suggesting this volcano uniquely responds to changes in the West Antarctic Ice Sheet. We propose to combine the petrology of Mount Waesche\u2019s volcanic record, constraints on changing ice loads through time, and geodynamic modelling to: (1) Determine how pre-eruptive storage conditions change during glacial and interglacial periods using whole rock and mineral compositions of volcanic rocks; (2) Conduct geodynamic modeling to elucidate the relationship between lithospheric structure, temporal variations in ice sheet thickness, and subsequent changes in crustal stresses and magmatic transport and, therefore, the mechanism(s) by which deglaciation impacts magmatic plumbing systems; (3) Use the outcomes of objectives (1) and (2) to provide new constraints on the changes in ice sheet thickness through time that could plausibly trigger future volcanic and magmatic activity in West Antarctica. This collaborative approach will provide a novel methodology to determine prior magnitudes and rates of ice load changes within the Marie Byrd Land region of Antarctica. Lastly, estimates of WAIS elevation changes from this study will be compared to ongoing studies at Mount Waesche focused on constraining last interglacial ice sheet draw down using cosmogenic exposure ages obtained from shallow drilling. The scope of work also includes a partnership with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online.", "east": -126.719922, "geometry": "POINT(-126.931765 -77.18824585)", "instruments": null, "is_usap_dc": true, "keywords": "Mt. Waesche; AMD/US; GEOCHEMISTRY; West Antarctica; Executive Committee Range; NOT APPLICABLE; USAP-DC; AMD; LITHOSPHERIC PLATE MOTION; MAJOR ELEMENTS; STRESS; USA/NSF; ROCKS/MINERALS/CRYSTALS", "locations": "West Antarctica; Mt. Waesche; Executive Committee Range", "north": -77.1380528, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Waters, Laura; Naliboff, John; Zimmerer, Matthew", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repositories": null, "science_programs": null, "south": -77.2384389, "title": "Integrating petrologic records and geodynamics: Quantifying the effects of glaciation on crustal stress and eruptive patterns at Mt. Waesche, Executive Committee Range, Antarctica", "uid": "p0010248", "west": -127.143608}, {"awards": "1947040 Postlethwait, John", "bounds_geometry": "POLYGON((-65.3 -63.3,-65 -63.3,-64.7 -63.3,-64.4 -63.3,-64.1 -63.3,-63.8 -63.3,-63.5 -63.3,-63.2 -63.3,-62.9 -63.3,-62.6 -63.3,-62.3 -63.3,-62.3 -63.47,-62.3 -63.64,-62.3 -63.81,-62.3 -63.98,-62.3 -64.15,-62.3 -64.32,-62.3 -64.49,-62.3 -64.66,-62.3 -64.83,-62.3 -65,-62.6 -65,-62.9 -65,-63.2 -65,-63.5 -65,-63.8 -65,-64.1 -65,-64.4 -65,-64.7 -65,-65 -65,-65.3 -65,-65.3 -64.83,-65.3 -64.66,-65.3 -64.49,-65.3 -64.32,-65.3 -64.15,-65.3 -63.98,-65.3 -63.81,-65.3 -63.64,-65.3 -63.47,-65.3 -63.3))", "dataset_titles": "18 SSU rDNA type sequences for Notoxcellia coronata (nov. sp.); 18 SSU rDNA type sequences for Notoxcellia picta (nov. sp.); Fish pictures and skin pathology of X-cell infection in Trematomus scotti.; Histopathology of X-cell xenomas in Trematomus scotti and Nototheniops larseni.; In situ hybridization of X-cell and host fish 18S SSU rRNA in alternate sections of tumor xenomas.; Metagenomic analysis of apparently healthy and tumor samples using Kaiju software ; microMRI analyses of Trematomus scotti Tsco_18_08 with X-cell xenomas; Morphological and pathological data of Trematomus scotti specimens captured on May 30th, 2018 in Andvord Bay.; Phylogenetic Analysis of Notoxcellia species.; Raw Illumina sequencing reads from skin tumors and visually healthy skins from Trematomus scotti and Nototheniops larseni; Temperature profiles at five fishing locations on the West Antarctic Peninsula during austral fall 2018.; Trematomus scotti with X-cell xenomas", "datasets": [{"dataset_uid": "601536", "doi": "10.15784/601536", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Cryosphere; Notoxcellia coronata; Notoxcellia picta; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; Murray, Katrina N. ; Desvignes, Thomas; Kent, Michael L. ", "repository": "USAP-DC", "science_program": null, "title": "Histopathology of X-cell xenomas in Trematomus scotti and Nototheniops larseni.", "url": "https://www.usap-dc.org/view/dataset/601536"}, {"dataset_uid": "601496", "doi": "10.15784/601496", "keywords": "Andvord Bay; Antarctica; Cryosphere; Fish", "people": "Postlethwait, John; Lauridsen, Henrik; Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Fish pictures and skin pathology of X-cell infection in Trematomus scotti.", "url": "https://www.usap-dc.org/view/dataset/601496"}, {"dataset_uid": "200276", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "18 SSU rDNA type sequences for Notoxcellia picta (nov. sp.)", "url": "https://www.ncbi.nlm.nih.gov/nuccore/OL630145"}, {"dataset_uid": "200275", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "18 SSU rDNA type sequences for Notoxcellia coronata (nov. sp.)", "url": "https://www.ncbi.nlm.nih.gov/nuccore/OL630144"}, {"dataset_uid": "200262", "doi": "", "keywords": null, "people": null, "repository": "MorphoSource", "science_program": null, "title": "Trematomus scotti with X-cell xenomas", "url": "https://www.morphosource.org/projects/000405843?locale=en"}, {"dataset_uid": "601539", "doi": "10.15784/601539", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Cryosphere; Notoxcellia coronata; Notoxcellia picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "In situ hybridization of X-cell and host fish 18S SSU rRNA in alternate sections of tumor xenomas.", "url": "https://www.usap-dc.org/view/dataset/601539"}, {"dataset_uid": "601538", "doi": "10.15784/601538", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Cryosphere; Notoxcellia coronata; Notoxcellia picta; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; Desvignes, Thomas; Lauridsen, Henrik", "repository": "USAP-DC", "science_program": null, "title": "microMRI analyses of Trematomus scotti Tsco_18_08 with X-cell xenomas", "url": "https://www.usap-dc.org/view/dataset/601538"}, {"dataset_uid": "601537", "doi": "10.15784/601537", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Cryosphere; Notoxcellia coronata; Notoxcellia picta; Perkinsozoa; Xcellidae", "people": "Desvignes, Thomas; Postlethwait, John; Varsani, Arvind; Kraberger, Simona ; Fontenele, Rafaela S. ", "repository": "USAP-DC", "science_program": null, "title": "Metagenomic analysis of apparently healthy and tumor samples using Kaiju software ", "url": "https://www.usap-dc.org/view/dataset/601537"}, {"dataset_uid": "601501", "doi": "10.15784/601501", "keywords": "Alveolata; Antarctica; Antarctic Peninsula; Biology; Biosphere; Cryosphere; Notoxcellia coronata; Notoxcellia picta; Oceans; Perkinsozoa; Xcellidae", "people": "Postlethwait, John; Desvignes, Thomas; Varsani, Arvind", "repository": "USAP-DC", "science_program": null, "title": "Phylogenetic Analysis of Notoxcellia species.", "url": "https://www.usap-dc.org/view/dataset/601501"}, {"dataset_uid": "200277", "doi": "", "keywords": null, "people": null, "repository": "NCBI SRA", "science_program": null, "title": "Raw Illumina sequencing reads from skin tumors and visually healthy skins from Trematomus scotti and Nototheniops larseni", "url": "https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA789574"}, {"dataset_uid": "601495", "doi": "10.15784/601495", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere", "people": "Desvignes, Thomas", "repository": "USAP-DC", "science_program": null, "title": "Temperature profiles at five fishing locations on the West Antarctic Peninsula during austral fall 2018.", "url": "https://www.usap-dc.org/view/dataset/601495"}, {"dataset_uid": "601494", "doi": "10.15784/601494", "keywords": "Andvord Bay; Antarctica; Cryosphere; Fish", "people": "Lauridsen, Henrik; Le Francois, Nathalie; Desvignes, Thomas; Postlethwait, John", "repository": "USAP-DC", "science_program": null, "title": "Morphological and pathological data of Trematomus scotti specimens captured on May 30th, 2018 in Andvord Bay.", "url": "https://www.usap-dc.org/view/dataset/601494"}], "date_created": "Thu, 01 Jul 2021 00:00:00 GMT", "description": "Overview:\r\nAntarctic biota face increasing stressors from warming oceans. A key question is: What will be the effect of warming waters on Antarctic biota? A gap in our knowledge is the identify of early harbingers of new stressors. In our recent field season, we unexpectedly discovered pink, wart-like neoplasms in Antarctic notothenioid fish, including Trematomus scotti (crowned notothen) and Nototheniops larseni (painted notothen). Neoplasms affected about 30% of T. scotti collected in Andvord Bay on the West Antarctic Peninsula and covered 10 to 30% of the bodies of affected individuals, usually in one contiguous patch. We collected samples from affected and apparently unaffected controls. We could not find evidence of any similar outbreak. Our overall goal is to learn the biological origins of this neoplasm and how it affects cellular function and organismal physiology. \r\nIntellectual Merit:\r\nAim 1: Pathogenic agents. Aim 1a: To test the hypothesis that a virus causes the neoplasm. Methods involve isolating and sequencing viral nucleic acids from neoplasms and from unaffected skin and comparing sequences to known viruses. Aim 1b: To test the hypothesis that neoplasms are hosts to parasites not present in healthy skin. Methods include tissue sections and DNA sequencing to find evidence of parasitic organisms. Significance: achieving Aim 1 will narrow down possible etiological agents. An untested possibility is that environmental contaminants cause the condition; exploring that hypothesis would require further sampling outside the limits of an EAGER proposal.\r\nAim 2: Cell-level pathology. Aim 2a: To test the hypothesis that the histopathology of the neoplasms is similar to other known skin neoplasias; alternatively, it might be a previously unknown type of neoplasia. Methods involve the examination of histological sections to identify pathology-specific characters. Aim 2b: To find effects of neoplasms on cell function. Methods involve performing whole-genome transcriptomics of affected and normal skin by RNA-seq and aligning reads to a T. scotti reference genome. Significance: achieving Aim 2 will define the cell biology and gene-expression phenotypes of the neoplasia, thus suggesting mechanisms that cause it.\r\n[Note: NSF deleted funds specifically to achieve the Aim 3, which nevertheless appears here to represent the original proposal.] Aim 3: Organismal pathology. Aim 3a: To test the hypothesis that the neoplasm has adverse effects on growth and physiology. Methods are to perform morphometrics in fish with neoplasms compared to age-matched controls from otolith studies. Aim 3b: To test the hypothesis that the neoplasia affects reproductive traits. Methods compare reproductive effort in affected and unaffected individuals. Significance: if the neoplasia has little consequences on growth and reproduction, our worry about its spread will be lessened, but if it is harmful, then Antarctic ecology, which largely depends on notothenioid fish, might be in danger.\r\nAchieving Aims 1-3 will advance knowledge by identifying the causes of a neoplasia outbreak in Antarctic fish. Work is potentially transformative because it might represent an early sign of Antarctic fish responses to the stress of global climate change. Proposed work would be the first to investigate a neoplasia outbreak in Antarctic fish. We will assess the project\u2019s success by whether we identify a causative agent and its effects on physiology.\r\nBroader Impacts:\r\nAim 4: Publicizing the neoplasia. We aim to raise awareness of the outbreak and publicize its distinct diagnostic features, including assays to detect it, by contributing to groups that track Antarctic ecosystems. \r\nAim 5: Inclusion. We will involve underrepresented groups in scientific research with authentic research experiences.\r\nAchieving Aims 4 and 5 will benefit society because they will disseminate to scientific and lay communities a potential early-warning system for the effects of an apparently new neoplasia affecting, at least locally, a large proportion of a fish population. Dissemination will stir research to determine whether this neoplasia outbreak is an isolated event or is becoming a general phenomenon, and thus a concern for Antarctic ecosystems. Proposed research will enhance research infrastructure by providing tools to identify the neoplasia. Finally, the project will broaden access to research careers by exposing underserved high school students and undergraduates to an exciting live research project.\r\n", "east": -62.3, "geometry": "POINT(-63.8 -64.15)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; PROTISTS; BENTHIC; FISH; Dallmann Bay; USAP-DC; Andvord Bay; NSF/USA; AMD/US; AMD", "locations": "Andvord Bay; Dallmann Bay", "north": -63.3, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Postlethwait, John; Varsani, Arvind; Desvignes, Thomas", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "GenBank; Other; USAP-DC", "science_programs": null, "south": -65.0, "title": "EAGER: Origin and Physiological Consequences of a Neoplasm Outbreak in Antarctic Fish ", "uid": "p0010221", "west": -65.3}, {"awards": "1543344 Soreghan, Gerilyn", "bounds_geometry": null, "dataset_titles": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "datasets": [{"dataset_uid": "601599", "doi": "10.15784/601599", "keywords": "Antarctica; Anza Borrego; Cryosphere; Iceland; McMurdo Dry Valleys; Norway; Peru; Puerto Rico; Taylor Valley; Washington; Wright Valley", "people": "Demirel-Floyd, Cansu", "repository": "USAP-DC", "science_program": null, "title": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "url": "https://www.usap-dc.org/view/dataset/601599"}], "date_created": "Tue, 18 May 2021 00:00:00 GMT", "description": "As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high \"weatherability\" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth\u0027s carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential \"weather ability\" and investigate how sediment produced in these glacial systems could ultimately impact Earth\u0027s carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.\r\n\r\nPhysical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; FIELD INVESTIGATION; weathering ; USA/NSF; Antarctica; AMD/US; Dry Valleys; SEDIMENT CHEMISTRY", "locations": "Antarctica; Dry Valleys", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soreghan, Gerilyn; Elwood Madden, Megan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems", "uid": "p0010181", "west": null}, {"awards": "1643618 Arrigo, Kevin; 1643652 Hofmann, Eileen", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Antarctic biological model output; Antarctic dFe model dyes", "datasets": [{"dataset_uid": "200211", "doi": "10.26008/1912/bco-dmo.858663.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic biological model output", "url": "https://www.bco-dmo.org/dataset/858663"}, {"dataset_uid": "200210", "doi": "10.26008/1912/bco-dmo.782848.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic dFe model dyes", "url": "https://www.bco-dmo.org/dataset/782848"}], "date_created": "Thu, 29 Apr 2021 00:00:00 GMT", "description": "Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail.\r\nThis project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings.\r\nThe project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts.\r\n\r\nPolynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers.\r\nIn this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for \u003e50% of the total Antarctic polynya production.\r\nThe research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent?\r\nThe Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "MICROALGAE; USA/NSF; trace metal; AMD; Polynas; TRACE ELEMENTS; PELAGIC; ICE SHEETS; Antarctica; AMD/US; POLYNYAS; PHYTOPLANKTON; MODELS; USAP-DC", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "van Dijken, Gert; Arrigo, Kevin; Dinniman, Michael; Hofmann, Eileen", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Elucidating Environmental Controls of Productivity in Polynas and the Western Antarctic Peninsula", "uid": "p0010175", "west": -180.0}, {"awards": "1543450 Countway, Peter", "bounds_geometry": "POLYGON((-66 -63,-65.7 -63,-65.4 -63,-65.1 -63,-64.8 -63,-64.5 -63,-64.2 -63,-63.9 -63,-63.6 -63,-63.3 -63,-63 -63,-63 -63.3,-63 -63.6,-63 -63.9,-63 -64.2,-63 -64.5,-63 -64.8,-63 -65.1,-63 -65.4,-63 -65.7,-63 -66,-63.3 -66,-63.6 -66,-63.9 -66,-64.2 -66,-64.5 -66,-64.8 -66,-65.1 -66,-65.4 -66,-65.7 -66,-66 -66,-66 -65.7,-66 -65.4,-66 -65.1,-66 -64.8,-66 -64.5,-66 -64.2,-66 -63.9,-66 -63.6,-66 -63.3,-66 -63))", "dataset_titles": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ; Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments; Western Antarctic Peninsula plankton raw sequence reads", "datasets": [{"dataset_uid": "601645", "doi": "10.15784/601645", "keywords": "Antarctica; Cryosphere; Nitrate; Nitrite; Palmer Station; Phosphate", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Inorganic Nutrient Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments ", "url": "https://www.usap-dc.org/view/dataset/601645"}, {"dataset_uid": "601647", "doi": "10.15784/601647", "keywords": "Antarctica; Cryosphere; Palmer Station; Phytoplankton", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Flow Cytometry Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601647"}, {"dataset_uid": "601646", "doi": "10.15784/601646", "keywords": "Antarctica; Carbon; Cryosphere; Dissolved Organic Carbon; DOC; Nitrogen; Palmer Station; TDN; Total Dissolved Nitrogen", "people": "Matrai, Patricia; Countway, Peter", "repository": "USAP-DC", "science_program": null, "title": "Dissolved Organic Carbon (DOC) and Total Dissolved Nitrogen (TDN) Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601646"}, {"dataset_uid": "601644", "doi": "10.15784/601644", "keywords": "3H-Leu; Antarctica; Bacteria; Biology; Cryosphere; DMSP; Heterotrophic Bacterial Production; Palmer Station", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Heterotrophic Bacterial Production Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601644"}, {"dataset_uid": "200337", "doi": "", "keywords": null, "people": null, "repository": "GenBank", "science_program": null, "title": "Western Antarctic Peninsula plankton raw sequence reads", "url": "https://dataview.ncbi.nlm.nih.gov/object/PRJNA870587?reviewer=bmud2tbbrqbus79i2n2hb83uio"}, {"dataset_uid": "601648", "doi": "10.15784/601648", "keywords": "Antarctica; Biology; Cryosphere; Dimethyl Sulfide; Dimethylsulfoniopropionate; Dimethylsulfoxide; DMSP; DMSP lyase; Palmer Station", "people": "Countway, Peter; Matrai, Patricia", "repository": "USAP-DC", "science_program": null, "title": "Biogenic Sulfur Samples from Station E (Palmer Station, Antarctica) and Associated Incubation Experiments", "url": "https://www.usap-dc.org/view/dataset/601648"}], "date_created": "Sat, 01 Aug 2020 00:00:00 GMT", "description": "The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\\DMS production. The project examined the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project interacted with elementary students in Maine and brought undergraduate students to Bigelow Laboratory. The project also engaged with a science writer and illustrator who joined the team in Palmer Station in 2018. Many posts are available at xxx\r\n\r\nThe project is examining (1) the extent to which the cycling of DMSP in southern ocean waters influenced the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influenced the magnitude and rates of DMSP cycling; we are awaiting results on (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to field experimental additions of DMSP; and, this year (2020-21), we will synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work was accomplished by conducting continuous growth experiments with DMSP-amended natural samples of different microbial communities present in summer (2016-17) and fall (2018) at Palmer Station, WAP. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis in the coming year (2020-21). ", "east": -63.0, "geometry": "POINT(-64.5 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "AMD/US; USAP-DC; COMMUNITY DYNAMICS; FIELD INVESTIGATION; BIOGEOCHEMICAL CYCLES; AMD; PLANKTON; Palmer Station; USA/NSF", "locations": "Palmer Station", "north": -63.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Countway, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "GenBank; USAP-DC", "science_programs": null, "south": -66.0, "title": "Microbial Community Structure and Expression of Functional Genes Involved in the Seasonal Cycling of DMSP in the Southern Ocean", "uid": "p0010120", "west": -66.0}, {"awards": "1543328 Van Mooy, Benjamin", "bounds_geometry": null, "dataset_titles": "Lipidomics of Antarctic waters. (TBD)", "datasets": [{"dataset_uid": "200149", "doi": "TBD", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Lipidomics of Antarctic waters. (TBD)", "url": "https://www.bco-dmo.org/data"}], "date_created": "Fri, 19 Jun 2020 00:00:00 GMT", "description": "The depletion of stratospheric ozone over Antarctica leads to abnormally high levels of ultraviolet radiation (UVR) from the sun reaching the surface of the ocean. This phenomenon is predicted to continue for the next half century, despite bans on ozone-destroying pollutants. Phytoplankton in the near surface ocean are subjected to variable amounts of UVR and contain a lot of lipids (fats). Because phytoplankton are at the base of the food chain their lipids makes their way into the Antarctic marine ecosystem\u0027s food web. The molecular structures of phytoplankton lipids are easily altered by UVR. When this happens, their lipids can be transformed from healthy molecules into potentially harmful molecules(oxylipins) known to be disruptive to reproductive and developmental processes. This project will use state-of-the-art molecular methods to answer questions about extent to which UVR damages lipid molecules in phytoplankton, and how these resultant molecules might effect the food chain in the ocean near Antarctica. \u003cbr/\u003e\u003cbr/\u003e\u003cbr/\u003eLipid peroxidation is often invoked as consequence of increased exposure of phytoplankton to UVR-produced reactive oxygen species (ROS), but the literature is practically silent on peroxidized lipids and their byproducts (i.e. oxylipins) in the ocean. In waters of the West Antarctic Peninsula (WAP), spring-time blooms of diatoms contribute significantly to overall marine primary production. Oxylipins from diatoms can be highly bioactive; their impact on zooplankton grazers, bacteria, and other phytoplankton has been the subject of intense study. However, almost all of this work has focused on the production of oxylipins via enzymatic pathways, not by pathways involving UVR and/or ROS. Furthermore, rigorous experimental work on the effects of oxylipins has been confined almost exclusively to pure cultures and artificial communities. Thus, the true potential of these molecules to disrupt carbon cycling is very poorly-constrained, and is entirely unknown in the waters of the WAP. Armed with new highly-sensitive, state-of-the-art analytical techniques based on high-mass-resolution mass spectrometry, the principal investigator and his research group have begun to uncover an exquisite diversity of oxylipins in natural WAP planktonic communities. These techniques will be applied to understand the connections between UVR, ROS, oxylipins, and carbon cycling. The project will answer the question of how UVR, via ROS, affects oxylipin production by diatoms in WAP surface waters in controlled experiments conducted at a field station. With the answer to this question in hand, the project will also seek to answer how this phenomenon impacts the flow of carbon, particularly the export of organic carbon from the system, during a research cruise. The level of UVR-induced stresses experienced by oxylipin-rich planktonic communities in the WAP is unique, making Antarctica the only location for answering these fundamental questions. Major activities will include laboratory experiments with artificial membranes and diatom cultures, as well field experiments with phytoplankton, zooplankton, and bacteria in WAP waters.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Oxylipins; USAP-DC; Palmer Station; West Antarctic Shelf; NOT APPLICABLE; AQUATIC SCIENCES; Phytoplankton ; UV Radiation", "locations": "West Antarctic Shelf; Palmer Station", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Van Mooy, Benjamin", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "BCO-DMO", "repositories": "BCO-DMO", "science_programs": null, "south": null, "title": "Production and Fate of Oxylipins in Waters of the Western Antarctic Peninsula: Linkages Between UV Radiation, Lipid Peroxidation, and Carbon Cycling", "uid": "p0010109", "west": null}, {"awards": "1341393 Denlinger, David; 1341385 Lee, Richard", "bounds_geometry": "POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))", "dataset_titles": "Alaskozetes antarcticus Raw sequence reads; Belgica antarctica Integrated Genome and Transcriptome Project; Data from: Rapid cold hardening protects against sublethal freezing injury in an Antarctic insect", "datasets": [{"dataset_uid": "200052", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Alaskozetes antarcticus Raw sequence reads", "url": "https://www.ncbi.nlm.nih.gov/bioproject/PRJNA428758"}, {"dataset_uid": "200053", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Belgica antarctica Integrated Genome and Transcriptome Project", "url": "https://www.ncbi.nlm.nih.gov/bioproject/175916"}, {"dataset_uid": "200054", "doi": " https://doi.org/10.5061/dryad.29p7ng2", "keywords": null, "people": null, "repository": "Dryad Digital Repository", "science_program": null, "title": "Data from: Rapid cold hardening protects against sublethal freezing injury in an Antarctic insect", "url": "https://datadryad.org/resource/doi:10.5061/dryad.29p7ng2"}], "date_created": "Mon, 12 Aug 2019 00:00:00 GMT", "description": "Polar regions are deserts that are not only cold but also lack access to free water. Antarctic insects have unique survival mechanisms including the ability to tolerate freezing and extensive dehydration, surviving the loss of 70% of their body water. How this is done is of interest not only for understanding seasonal adaptations of insects and how they respond to climate change, but the molecular and physiological mechanisms employed may offer valuable insights into more general mechanisms that might be exploited for cryopreservation and long-term storage of human tissues and organs for transplantation and other medical applications. The investigators will study the proteins that are responsible for removing water from the body, cell level consequences of this, and how the responsible genes vary between populations. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Each year a K-12 teacher will be a member of the field team and assist with fieldwork and outreach to school children and their teachers. Educational outreach efforts include presentations at local schools and national teacher meetings, providing lesson plans and podcasts on a website, and continuing to publish articles related to this research in education journals. In addition, undergraduate and graduate students will receive extensive training in all aspects of the research project with extended experiences that include publication of scientific papers and presentations at national meetings.\u003cbr/\u003e\u003cbr/\u003eThis project focuses on deciphering the physiological and molecular mechanisms that enable the Antarctic midge Belgica antarctica to survive environmental stress and the loss of most of its body water in the desiccating polar environment. This extremophile is an ideal system for investigating mechanisms of stress tolerance and local geographic adaptations and its genome has recently been sequenced. This project has three focal areas: 1) Evaluating the role of aquaporins (water channel proteins) in the rapid removal of water from the body by studying expression of their genes during dehydration; 2) Investigating the mechanism of metabolic depression and the role of autophagy (controlled breakdown of cellular components) as a mediator of stress tolerance by studying expression of the genes responsible for autophagy during the dehydration process; and 3) Evaluating the population structure, gene flow, and adaptive variation in physiological traits associated with stress tolerance using a genetic approach that takes advantage of the genomic sequence available for this species coupled with physiological and environmental data from the sampled populations and their habitats.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "Antarctica; USAP-DC; ARTHROPODS; NOT APPLICABLE", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Denlinger, David; Lee, Richard", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "Other", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Winter Survival Mechanisms and Adaptive Genetic Variation in an Antarctic Insect", "uid": "p0010048", "west": -180.0}, {"awards": "1247510 Detrich, H. William", "bounds_geometry": null, "dataset_titles": "E-MTAB-6759: RNA-seq across tissues in four Notothenioid species (Antarctic icefish); Expedition Data; Expedition data of LMG1003; Expedition data of LMG1004; PRJNA420419: Chaenocephalus aceratus Genome sequencing; PRJNA66471: Notothenia coriiceps Genome Sequencing Notothenia coriiceps isolate:Sejong01 (black rockcod); S-BSST 132: Assembled Transcriptomes for Berthelot et al. (2018); SRA091269: Notothenia coriiceps RNA Raw Sequence Reads; SRP047484: RAD-tag Sequences of Genetically Mapped Notothenia coriiceps Embryos ; SRP118539: RAD-tag Sequences of Genetically Mapped Chaenocephalus aceratus Embryos", "datasets": [{"dataset_uid": "200144", "doi": "", "keywords": null, "people": null, "repository": "Array Express", "science_program": null, "title": "E-MTAB-6759: RNA-seq across tissues in four Notothenioid species (Antarctic icefish)", "url": "https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-6759/"}, {"dataset_uid": "002685", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1004", "url": "https://www.rvdata.us/search/cruise/LMG1004"}, {"dataset_uid": "200145", "doi": "", "keywords": null, "people": null, "repository": "BioStudies", "science_program": null, "title": "S-BSST 132: Assembled Transcriptomes for Berthelot et al. (2018)", "url": "https://www.ebi.ac.uk/biostudies/studies/S-BSST132"}, {"dataset_uid": "002684", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG1003", "url": "https://www.rvdata.us/search/cruise/LMG1003"}, {"dataset_uid": "200093", "doi": "", "keywords": null, "people": null, "repository": "NCBI Sequence Read Archive", "science_program": null, "title": "SRP118539: RAD-tag Sequences of Genetically Mapped Chaenocephalus aceratus Embryos", "url": "https://www.ncbi.nlm.nih.gov/sra/SRP118539 "}, {"dataset_uid": "200146", "doi": "", "keywords": null, "people": null, "repository": "NCBI Sequence Read Archive", "science_program": null, "title": "SRP047484: RAD-tag Sequences of Genetically Mapped Notothenia coriiceps Embryos ", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRP047484"}, {"dataset_uid": "001508", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0807"}, {"dataset_uid": "001509", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0806"}, {"dataset_uid": "200026", "doi": "", "keywords": null, "people": null, "repository": "NCBI Sequence Read Archive", "science_program": null, "title": "SRA091269: Notothenia coriiceps RNA Raw Sequence Reads", "url": "https://www.ncbi.nlm.nih.gov/sra/?term=SRA091269"}, {"dataset_uid": "200142", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "PRJNA66471: Notothenia coriiceps Genome Sequencing Notothenia coriiceps isolate:Sejong01 (black rockcod)", "url": "https://www.ncbi.nlm.nih.gov/bioproject/66471"}, {"dataset_uid": "200143", "doi": "", "keywords": null, "people": null, "repository": "NCBI BioProject", "science_program": null, "title": "PRJNA420419: Chaenocephalus aceratus Genome sequencing", "url": "https://www.ncbi.nlm.nih.gov/bioproject/420419"}], "date_created": "Mon, 08 Apr 2019 00:00:00 GMT", "description": "Since the advent of Antarctic continental glaciation, the opening of the Drake Passage between South America and the Antarctic Peninsula, and the onset of cooling of the Southern Ocean ~40-25 million years ago, evolution of the Antarctic marine biota has been driven by the development of extreme cold temperatures. As circum-Antarctic coastal temperatures declined during this period from ~20\u00b0C to the modern -1.9 to +2.0\u00b0C (reached ~8-10 million years ago), the psychrophilic (cold-loving) ectotherms of the Southern Ocean evolved compensatory molecular, cellular, and physiological traits that enabled them to maintain normal metabolic function at cold temperatures. Today, these organisms are threatened by rapid warming of the Southern Ocean over periods measured in centuries (as much as 5\u00b0C/100 yr), a timeframe so short that re-adaptation and/or acclimatization to the \"new warm\" may not be possible. Thus, the long-term goals of this research project are: 1) to understand the biochemical and physiological capacities of the embryos of Antarctic notothenioid fish to resist or compensate for rapid oceanic warming; and 2) to assess the genetic toolkit available to support the acclimatization and adaptation of Antarctic notothenioid embryos to their warming habitat. The specific aims of this work are: 1) to determine the capacity of the chaperonin complex of notothenioid fishes to assist protein folding at temperatures between -4 and +20\u00b0C; and 2) to evaluate the genetic responses of notothenioid embryos, measured as global differential gene transcription, to temperature challenge, with -1.9\u00b0C as the \"normal\" control and +4 and +10\u00b0C as high temperature insults.\r\nThe physiology of embryonic development of marine stenotherms under future climate change scenarios is an important but understudied problem. This project will provide valuable insights into the capacity of Antarctic fish embryos to acclimatize and adapt to plausible climate change scenarios by examining multiple levels of biological organization, from the biochemical to the organismal. The results should also be broadly applicable to understanding the impact of global warming on marine biota worldwide. The research will also introduce graduate and undergraduate students to state-of-the-art biochemical, cellular, and molecular-biological research relevant to ecological and environmental issues of the Antarctic marine ecosystem.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e TRAWLS/NETS \u003e BOTTOM TRAWL", "is_usap_dc": false, "keywords": "AQUATIC SCIENCES; R/V LMG; USAP-DC; Southern Ocean", "locations": "Southern Ocean", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Detrich, H. William", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "Array Express", "repositories": "Other", "science_programs": null, "south": null, "title": "Protein Folding and Embryogenesis in Antarctic Fishes: A Comparative Approach to Environmental Stress", "uid": "p0010024", "west": null}, {"awards": "1743326 Kingslake, Jonathan", "bounds_geometry": null, "dataset_titles": "Report on Antarctic surface hydrology workshop, LDEO, 2018 ", "datasets": [{"dataset_uid": "601170", "doi": "10.15784/601170", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Hydrology; Ice-Sheet Stability; Ice Shelf; Report; Workshop", "people": "DeConto, Robert; Schoof, Christian; Lenaerts, Jan; Tedesco, Marco; Das, Indrani; Bell, Robin; Banwell, Alison; Trusel, Luke; Kingslake, Jonathan", "repository": "USAP-DC", "science_program": null, "title": "Report on Antarctic surface hydrology workshop, LDEO, 2018 ", "url": "https://www.usap-dc.org/view/dataset/601170"}], "date_created": "Tue, 26 Mar 2019 00:00:00 GMT", "description": "Ice shelves are the floating portions of glaciers that terminate in the ocean. They are common around the periphery of Antarctica. The accumulation of surface meltwater on or near the surface of ice shelves can play a role in ice-shelf collapse, which leads to accelerated loss of grounded ice and sea-level rise. Recent studies have showed that present-day meltwater generation and movement across the surface of Antarctica is more widespread than previously thought and is expected to increase. Consequently, there is a growing need to address the role of surface water in forecasts of ice-shelf behavior. While much progress has been made, understanding of the role of water in ice-shelf collapse is still in its infancy. This award supports a workshop that will bring together experts from multiple disciplines that, together, can advance understanding of Antarctic surface hydrology and its role in the future stability of ice shelves. This workshop will bring together U.S. and international scientists with expertise in ice-sheet dynamics, glacial hydrology, climatology, and other disciplines to identify critical knowledge gaps and move the community towards answering fundamental questions such as: What climate dynamics are responsible for surface meltwater generation in Antarctica? What controls the spatiotemporal distribution of meltwater ponds on Antarctic ice shelves? Where is meltwater generated, where does it pond today, and how will this change this century? How will meltwater impact ice shelves? How will surface hydrology impact sea-level this century? The deliberations will be captured in a workshop report.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; ICE SHEETS; North America; USAP-DC", "locations": "North America", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Kingslake, Jonathan; Tedesco, Marco; Trusel, Luke", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Workshop on Antarctic Surface Hydrology and Future Ice-shelf Stability", "uid": "p0010021", "west": null}, {"awards": "1245915 Ray, Laura", "bounds_geometry": null, "dataset_titles": "Ground Penetrating Radar Grid Survey of the McMurdo Shear Zone", "datasets": [{"dataset_uid": "601102", "doi": "10.15784/601102", "keywords": "Antarctica; Cryosphere; Firn; Folds; Geology/Geophysics - Other; Glaciers/Ice Sheet; Glaciology; GPR; Snow/Ice", "people": "Arcone, Steven; Kaluzienski, Lynn; Koons, Peter; Lever, Jim; Walker, Ben; Ray, Laura", "repository": "USAP-DC", "science_program": null, "title": "Ground Penetrating Radar Grid Survey of the McMurdo Shear Zone", "url": "https://www.usap-dc.org/view/dataset/601102"}], "date_created": "Thu, 27 Sep 2018 00:00:00 GMT", "description": "This award supports an integrated field observation, remote sensing and numerical modeling study of the McMurdo Shear Zone (SZ). The SZ is a 5-10 km wide strip of heavily crevassed ice that separates the McMurdo and Ross ice shelves, and is an important region of lateral support for the Ross Ice Shelf. Previous radar and remote sensing studies reveal an enigmatic picture of the SZ in which crevasses detected at depth have no apparent surface expression, and have orientations which are possibly inconsistent with the observed flow field. In the proposed work, we seek to test the hypothesis that the SZ is a zone of chaotic Lagrangian mixing with (intersecting) buried crevasses which leads to rheological instability, potentially allowing large scale velocity discontinuities. The work will involve detailed field-based observations of crevasse distributions and structure using ground-penetrating radar, and GPS and remote sensing observations of the flow and stress field in the SZ. Because of the hazardous nature of the SZ, the radar surveys will be conducted largely with the aid of a lightweight robotic vehicle. Observations will be used to develop a finite element model of ice shelf shear margin behavior. The intellectual merit of this project is an increased understanding of ice shelf shear margin dynamics. Shear margins play a key role in ice shelf stability, and ice shelves in turn modulate the flux of ice from the ice sheet across the grounding line to the ocean. Insights from this project will improve large-scale models being developed to predict ice sheet evolution and future rates of sea level rise, which are topics of enormous societal concern. The broader impacts of the project include an improved basis for US Antarctic Program logistics planning as well as numerous opportunities to engage K-12 students in scientific discovery. Intensified crevassing in the shear zone between the Ross and McMurdo ice shelves would preclude surface crossing by heavy traverse vehicles which would lead to increased costs of delivering fuel to South Pole and a concomitant loss of flight time provided by heavy-lift aircraft for science missions on the continent. Our multidisciplinary research combining glaciology, numerical modeling, and robotics engineering is an engaging way to show how robotics can assist scientists in collecting hazardous field measurements. Our outreach activities will leverage Dartmouth\u0027s current NSF GK-12 program, build on faculty-educator relationships established during University of Maine\u0027s recent GK-12 program, and incorporate project results into University of Maine\u0027s IDEAS initiative, which integrates computational modeling with the existing science curriculum at the middle school level. This award has field work in Antarctica.", "east": null, "geometry": null, "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Ray, Laura", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Flow and Fracture Dynamics in an Ice Shelf Lateral Margin: Observations and Modeling of the McMurdo Shear Zone", "uid": "p0000701", "west": null}, {"awards": "1141936 Foreman, Christine", "bounds_geometry": "POINT(112.085 -79.467)", "dataset_titles": "Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core", "datasets": [{"dataset_uid": "600133", "doi": "10.15784/600133", "keywords": "Antarctica; Biology; Biosphere; Cryosphere; Genetic Sequences; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Foreman, Christine", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core", "url": "https://www.usap-dc.org/view/dataset/600133"}], "date_created": "Thu, 05 Nov 2015 00:00:00 GMT", "description": "This award supports a detailed, molecular level characterization of dissolved organic carbon and microbes in Antarctic ice cores. Using the most modern biological (genomic), geochemical techniques, and advanced chemical instrumentation researchers will 1) optimize protocols for collecting, extracting and amplifying DNA from deep ice cores suitable for use in next generation pyrosequencing; 2) determine the microbial diversity within the ice core; and 3) obtain and analyze detailed molecular characterizations of the carbon in the ice by ultrahigh resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS). With this pilot study investigators will be able to quantify the amount of material (microbial biomass and carbon) required to perform these characterizations, which is needed to inform future ice coring projects. The ultimate goal will be to develop protocols that maximize the yield, while minimizing the amount of ice required. The broader impacts include education and outreach at both the local and national levels. As a faculty mentor with the American Indian Research Opportunities and BRIDGES programs at Montana State University, Foreman will serve as a mentor to a Native American student in the lab during the summer months. Susan Kelly is an Education and Outreach Coordinator with a MS degree in Geology and over 10 years of experience in science outreach. She will coordinate efforts for comprehensive educational collaboration with the Hardin School District on the Crow Indian Reservation in South-central Montana.", "east": 112.085, "geometry": "POINT(112.085 -79.467)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e ADS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "LABORATORY; Dissolved Organic Carbon; WAIS divide; FIELD SURVEYS; Microbes; Ice Core; Not provided; molecular; Antarctic; FIELD INVESTIGATION; Microbial Diversity; pyrosequencing; DNA", "locations": "Antarctic; WAIS divide", "north": -79.467, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Foreman, Christine", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -79.467, "title": "Molecular Level Characterization of Dissolved Organic Carbon and Microbial Diversity in the WAIS Divide Replicate Core", "uid": "p0000342", "west": 112.085}, {"awards": "1043421 Severinghaus, Jeffrey; 1043522 Brook, Edward", "bounds_geometry": "POINT(-112.09 -79.47)", "dataset_titles": "WAIS Divide Replicate Core Methane Isotopic Data Set", "datasets": [{"dataset_uid": "601059", "doi": "10.15784/601059", "keywords": "Antarctica; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Paleoclimate; WAIS divide; WAIS Divide Ice Core", "people": "Brook, Edward J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "WAIS Divide Replicate Core Methane Isotopic Data Set", "url": "https://www.usap-dc.org/view/dataset/601059"}], "date_created": "Mon, 13 Jul 2015 00:00:00 GMT", "description": "1043421/Severinghaus\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to obtain samples of ice in selected intervals for replication and verification of the validity and spatial representativeness of key results in the WAIS Divide ice core, and to obtain additional ice samples in areas of intense scientific interest where demand is high. The US Ice Core Working Group recommended in 2003 that NSF pursue the means to take replicate samples, termed \"replicate coring\". This recommendation was part of an agreement to reduce the diameter of the (then) new drilling system (the DISC drill) core to 12.2 cm to lighten logistics burdens, and the science community accepted the reduction in ice sample with the understanding that replicate coring would be able to provide extra sample volume in key intervals. The WAIS Divide effort would particularly benefit from replicate coring, because of the unique quality of the expected gas record and the large samples needed for gases and gas isotopes; thus this proposal to employ replicate coring at WAIS Divide. In addition, scientific demand for ice samples has been, and will continue to be, very unevenly distributed, with the ice core archive being completely depleted in depth intervals of high scientific interest (abrupt climate changes, volcanic sulfate horizons, meteor impact horizons, for example). The broader impacts of the proposed research may include identification of leads and lags between Greenland, tropical, and Antarctic climate change, enabling critical tests of hypotheses for the mechanism of abrupt climate change. Improved understanding of volcanic impacts on atmospheric chemistry and climate may also emerge. This understanding may ultimately help improve climate models and prediction of the Earth System feedback response to ongoing human perturbation in coming centuries. Outreach and public education about climate change are integral components of the PIs\u0027 activities and the proposed work will enhance these efforts. Broader impacts also include education and training of 2 postdoctoral scholars and 1 graduate student, and invaluable field experience for the graduate and undergraduate students who will likely make up the core processing team at WAIS Divide.", "east": -112.09, "geometry": "POINT(-112.09 -79.47)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": false, "keywords": "FIELD SURVEYS; mass spectrometery; Not provided; Ice Core Gas Records; Firn Air Isotopes; WAIS divide; FIELD INVESTIGATION; LABORATORY; Ice Core", "locations": "WAIS divide", "north": -79.47, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Glaciology; Antarctic Earth Sciences; Antarctic Glaciology", "paleo_time": null, "persons": "Severinghaus, Jeffrey P.; Brook, Edward J.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -79.47, "title": "Collaborative Research: Replicate Coring at WAIS Divide to Obtain Additional Samples at Events of High Scientific Interest", "uid": "p0000751", "west": -112.09}, {"awards": "0944193 MacAyeal, Douglas", "bounds_geometry": null, "dataset_titles": "Iceberg Capsize Kinematics and Energetics", "datasets": [{"dataset_uid": "609590", "doi": "10.7265/N56H4FCJ", "keywords": "Antarctica; Cryosphere; Glaciology; Iceberg; Kinetics", "people": "MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Iceberg Capsize Kinematics and Energetics", "url": "https://www.usap-dc.org/view/dataset/609590"}], "date_created": "Mon, 25 Aug 2014 00:00:00 GMT", "description": "This award supports a project to examine and test a 3-step process model for explosive ice-shelf disintegration that emerged in the wake of the recent 2008 and 2009 events of the Wilkins Ice Shelf. The model is conditioned on Summer melt-driven increase in free-surface water coupled with surface and basal crevasse density growth necessary to satisfy an \"enabling condition\". Once met, the collapse proceeds through three steps: (Step 1), calving of a \"leading phalanx\" of tabular icebergs from the seaward ice front of the ice shelf which creates in its wake a region, called a \"mosh pit\" (located between the phalanx and the edge of the intact ice shelf), where ocean surface-gravity waves are trapped by reflection (a fast mechanically enabled process), (Step 2), and a rapid, runaway conversion of gravitational potential energy into ocean-wave energy by iceberg capsize and fragmentation within the \"mosh pit\" which leads to further wave-induced calving, capsize and fragmentation (Step 3). The project will be conducted by a multidisciplinary team and will focus on theoretical model development, numerical method development and application and new observations. The project will participate in both the Research Experience for Undergraduates program in the Physics Department and the Summer Research Early Identification Program (SR-EIP) that fosters participation in research by underrepresented minorities. The PIs, postdoctoral scholar, graduate students and unfunded participants will develop a graduate-level seminar/tutorial to introduce advanced computational methods to glaciology. A postdoctoral scholar and graduate student will be trained in new research techniques during the project.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e CAMERAS \u003e VIDEO CAMERA", "is_usap_dc": true, "keywords": "AGDC-project; LABORATORY; iceberg velocity; iceberg kinetic engergy", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "MacAyeal, Douglas", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Collaborative Research: Explosive Ice-Shelf Disintegration", "uid": "p0000005", "west": null}, {"awards": "0944475 Kaplan, Michael", "bounds_geometry": "POLYGON((-149.7 -84.1,-118.61 -84.1,-87.52 -84.1,-56.43 -84.1,-25.34 -84.1,5.75 -84.1,36.84 -84.1,67.93 -84.1,99.02 -84.1,130.11 -84.1,161.2 -84.1,161.2 -84.43,161.2 -84.76,161.2 -85.09,161.2 -85.42,161.2 -85.75,161.2 -86.08,161.2 -86.41,161.2 -86.74,161.2 -87.07,161.2 -87.4,130.11 -87.4,99.02 -87.4,67.93 -87.4,36.84 -87.4,5.75 -87.4,-25.34 -87.4,-56.43 -87.4,-87.52 -87.4,-118.61 -87.4,-149.7 -87.4,-149.7 -87.07,-149.7 -86.74,-149.7 -86.41,-149.7 -86.08,-149.7 -85.75,-149.7 -85.42,-149.7 -85.09,-149.7 -84.76,-149.7 -84.43,-149.7 -84.1))", "dataset_titles": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "datasets": [{"dataset_uid": "600115", "doi": "10.15784/600115", "keywords": "Antarctica; Cosmogenic Dating; Cryosphere; Sample/Collection Description; Solid Earth; Transantarctic Mountains", "people": "Kaplan, Michael", "repository": "USAP-DC", "science_program": null, "title": "Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "url": "https://www.usap-dc.org/view/dataset/600115"}], "date_created": "Thu, 17 Jul 2014 00:00:00 GMT", "description": "The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica?s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed \u003c2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. \u003cbr/\u003e\u003cbr/\u003eBroader Impact \u003cbr/\u003eThe proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.", "east": 161.2, "geometry": "POINT(5.75 -85.75)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD INVESTIGATION", "locations": null, "north": -84.1, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Kaplan, Michael", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -87.4, "title": "Collaborative Research: Pleistocene East Antarctic Ice Sheet History as Recorded in Sediment Provenance and Chronology of High-elevation TAM Moraines", "uid": "p0000459", "west": -149.7}, {"awards": "0944248 MacAyeal, Douglas", "bounds_geometry": "POLYGON((-63.72 -63.73,-62.893 -63.73,-62.066 -63.73,-61.239 -63.73,-60.412 -63.73,-59.585 -63.73,-58.758 -63.73,-57.931 -63.73,-57.104 -63.73,-56.277 -63.73,-55.45 -63.73,-55.45 -64.0876,-55.45 -64.4452,-55.45 -64.8028,-55.45 -65.1604,-55.45 -65.518,-55.45 -65.8756,-55.45 -66.2332,-55.45 -66.5908,-55.45 -66.9484,-55.45 -67.306,-56.277 -67.306,-57.104 -67.306,-57.931 -67.306,-58.758 -67.306,-59.585 -67.306,-60.412 -67.306,-61.239 -67.306,-62.066 -67.306,-62.893 -67.306,-63.72 -67.306,-63.72 -66.9484,-63.72 -66.5908,-63.72 -66.2332,-63.72 -65.8756,-63.72 -65.518,-63.72 -65.1604,-63.72 -64.8028,-63.72 -64.4452,-63.72 -64.0876,-63.72 -63.73))", "dataset_titles": "Go to the NSIDC and search for the data.; Standing Water Depth on Larsen B Ice Shelf", "datasets": [{"dataset_uid": "001996", "doi": "", "keywords": null, "people": null, "repository": "NSIDC", "science_program": null, "title": "Go to the NSIDC and search for the data.", "url": "http://nsidc.org"}, {"dataset_uid": "609584", "doi": "10.7265/N500002K", "keywords": "Antarctica; Antarctic Peninsula; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Shelf; Larsen B Ice Shelf; Sample/Collection Description; Supraglacial Meltwater", "people": "MacAyeal, Douglas", "repository": "USAP-DC", "science_program": null, "title": "Standing Water Depth on Larsen B Ice Shelf", "url": "https://www.usap-dc.org/view/dataset/609584"}], "date_created": "Sat, 21 Dec 2013 00:00:00 GMT", "description": "MacAyeal/0944248\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a better understanding of the processes and conditions that trigger ice shelf instability and explosive disintegration. A significant product of the proposed research will be the establishment of parameterizations of micro- and meso-scale ice-shelf surface processes needed in large scale ice-sheet models designed to predict future sea level rise. The proposed research represents a 3-year effort to conduct numerical model studies of 6 aspects of surface-water evolution on Antarctic ice shelves. These 6 model-study areas include energy balance models of melting ice-shelf surfaces, with treatment of surface ponds and water-filled crevasses, distributed, Darcian water flow modeling to simulate initial firn melting, brine infiltration, pond drainage and crevasse filling, ice-shelf surface topography evolution modeling by phase change (surface melting and freezing), surface-runoff driven erosion and seepage flows, mass loading and flexure effects of ice-shelf and iceberg surfaces; feedbacks between surface-water loads and flexure stresses; possible seiche phenomena of the surface water, ice and underlying ocean that constitute a mechanism for, inducing surface crevassing., surface pond and crevasse convection, and basal crevasse thermohaline convection (as a phenomena related to area 5 above). The broader impacts of the proposed work bears on the socio-environmental concerns of climate change and sea-level rise, and will contribute to the important goal of advising public policy. The project will form the basis of a dissertation project of a graduate student whose training will contribute to the scientific workforce of the nation and the PI and graduate student will additionally participate in a summer science-enrichment program for high-school teachers organized by colleagues at the University of Chicago.", "east": -55.45, "geometry": "POINT(-59.585 -65.518)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e ETM+; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e PHOTON/OPTICAL DETECTORS \u003e PHOTOMETERS \u003e SPECTROPHOTOMETERS", "is_usap_dc": true, "keywords": "melt ponds; standing water depth; Breakup of Larsen B Ice Shelf; ice shelf stability; LANDSAT-7; supraglacial lake", "locations": null, "north": -63.73, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "MacAyeal, Douglas", "platforms": "SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e LANDSAT \u003e LANDSAT-7", "repo": "NSIDC", "repositories": "NSIDC; USAP-DC", "science_programs": null, "south": -67.306, "title": "Model Studies of Surface Water Behavior on Ice Shelves", "uid": "p0000052", "west": -63.72}, {"awards": "1043367 Aciego, Sarah", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Fri, 01 Nov 2013 00:00:00 GMT", "description": "Aciego/1043367\u003cbr/\u003e\u003cbr/\u003eThis award supports the development of a new method for determining the absolute age of samples from deep ice cores. The project will: (1) prove the efficacy of the Uranium-series dating method on a high accumulation rate ice core, and (2) address the uncertainties in the age dating of the EPICA Dronning-Maud Land (EDML) ice core in the lower 300 m. The well-dated upper section of the ice core (down to 150,000 years at 2415.7 m) will provide excellent constraints to validate the ages determined by the U-series method. After verification, and possible adjustments to the laboratory chemistry, the method will be applied to a suite of ice samples of unknown age in the lower part of the EDML ice core. Within the lower 300 m of this ice core, the climate records are disturbed by tilting and folding of the ice, and, due to the uncertainties in how the ice has flowed, it is impossible to determine if accurate age dates can be obtained to access the record of climate change, or if mixing of the ice is too incoherent. As part of the methodology, the PI will measure surface area of dust included in the ice using a gas adsorption technique developed for ultra-small samples; these measurements will be made on a BET nano-scale which is to be purchased from the funding of this project. Intellectual Merit: The proposed research will contribute to our understanding of geophysical processes that fold and tilt ice. This will allow new paleoclimate records to be recovered from ice cores that have been physically deformed and disturbed and previously did not permit accurate dating. Broader Impacts: This funding will provide support for one PhD graduate student and contribute to their training as a researcher in geochemistry and paleoclimate studies. The PI will teach classes in earth surface processes (including glaciology) and in advanced isotope geochemistry. Work related to this research will be integrated as a teaching tool into the classroom to provide a hands-on, relevant learning experience. Furthermore, samples examined as part of this research will be made available from the AWI archive in Bremerhaven, Germany as part of the collaboration between the PI in the United States and the European ice core community.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Instrumentation and Support", "paleo_time": null, "persons": "Aciego, Sarah", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Detangling Flow Regimes and Paleoclimate in the Deepest Section of the EDML Ice Core using U-series Ages.", "uid": "p0000712", "west": null}, {"awards": "0125890 Sidell, Bruce", "bounds_geometry": "POLYGON((-68.1413 -52.6755,-67.47503 -52.6755,-66.80876 -52.6755,-66.14249 -52.6755,-65.47622 -52.6755,-64.80995 -52.6755,-64.14368 -52.6755,-63.47741 -52.6755,-62.81114 -52.6755,-62.14487 -52.6755,-61.4786 -52.6755,-61.4786 -53.8957,-61.4786 -55.1159,-61.4786 -56.3361,-61.4786 -57.5563,-61.4786 -58.7765,-61.4786 -59.9967,-61.4786 -61.2169,-61.4786 -62.4371,-61.4786 -63.6573,-61.4786 -64.8775,-62.14487 -64.8775,-62.81114 -64.8775,-63.47741 -64.8775,-64.14368 -64.8775,-64.80995 -64.8775,-65.47622 -64.8775,-66.14249 -64.8775,-66.80876 -64.8775,-67.47503 -64.8775,-68.1413 -64.8775,-68.1413 -63.6573,-68.1413 -62.4371,-68.1413 -61.2169,-68.1413 -59.9967,-68.1413 -58.7765,-68.1413 -57.5563,-68.1413 -56.3361,-68.1413 -55.1159,-68.1413 -53.8957,-68.1413 -52.6755))", "dataset_titles": "Expedition Data; Expedition data of LMG0304; Expedition data of LMG0304A", "datasets": [{"dataset_uid": "001704", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0304"}, {"dataset_uid": "002708", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0304A", "url": "https://www.rvdata.us/search/cruise/LMG0304A"}, {"dataset_uid": "002707", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0304A", "url": "https://www.rvdata.us/search/cruise/LMG0304A"}, {"dataset_uid": "002706", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0304", "url": "https://www.rvdata.us/search/cruise/LMG0304"}, {"dataset_uid": "001596", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0506"}, {"dataset_uid": "001597", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0505"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "Notothenioid fishes that dominate the fish fauna surrounding Antarctica have been evolving for 10-14 million years at a nearly constant body temperature of ~0C throughout their life histories. As a result, this group of animals is uniquely suited to studies aimed at understanding and identifying features of physiology and biochemistry that result from the process of evolution at cold body temperature. This project has three major objectives aimed at examining adaptations for life in cold environments: \u003cbr/\u003e\u003cbr/\u003e1. Identify the amino acid substitutions in the fatty acid-binding pocket of fatty acyl CoA synthetase (FACS) that explain its substrate specificity. Fatty acids are a major fuel of energy metabolism in Antarctic fishes. FACS catalyzes the condensation of CoASH and fatty acids to fatty acyl CoA esters, a step required for subsequent metabolism of these important compounds. This research may permit us to resolve the specific amino acid substitutions that explain both substrate specificity and preservation of catalytic rate of notothenioid FACS at cold physiological temperatures.\u003cbr/\u003e\u003cbr/\u003e2. Produce a rigorous biochemical and biophysical characterization of the intracellular calcium-binding protein, parvalbumin, from white axial musculature of Antarctic fishes. Parvalbumin plays a pivotal role in facilitating the relaxation phase of fast-contracting muscles and is a likely site of strong selective pressure. Preliminary data strongly indicate that the protein from Antarctic fishes has been modified to ensure function at cold temperature. A suite of physical techniques will be used to determine dissociation constants of Antarctic fish parvalbumins for calcium and magnesium and unidirectional rate constants of ion-dissociation from the protein. Full-length cDNA clones for Antarctic fish parvalbumin(s) will permit deduction of primary amino acid sequence These data will yield insight into structural elements that permit the protein from notothenioid fishes to function at very cold body temperature.\u003cbr/\u003e\u003cbr/\u003e3. Conduct a broad survey of the pattern of cardiac myoglobin expression in the Suborder Notothenoidei. Previous work has indicated a variable pattern of presence or absence of the intracellular oxygen-binding protein, myoglobin (Mb), in hearts of one family of Antarctic notothenioid fishes (Channichthyidae; icefishes). Because Mb is of physiological value in species that express the protein, the observed pattern of interspecific expression has been attributed to unusually low niche competition in the Southern Ocean. This leads to the prediction that similar loss of cardiac Mb should be observed in other notothenioid taxa. This part of the project will survey for the presence and absence of cardiac Mb in as many notothenioid species as possible and, if Mb-lacking species are detected, will extend analyses to determine the mechanism(s) responsible for loss of its expression using molecular biological techniques.", "east": -61.4786, "geometry": "POINT(-64.80995 -58.7765)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": -52.6755, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Sidell, Bruce; Detrich, H. William", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "Other", "science_programs": null, "south": -64.8775, "title": "Cold Body Temperature as an Evolutionary Shaping force in the Physiology of Antarctic Fishes", "uid": "p0000241", "west": -68.1413}, {"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": "0551163 Sidor, Christian; 0440954 Miller, Molly; 0440919 Isbell, John", "bounds_geometry": "POLYGON((159.3 -76.59,159.542 -76.59,159.784 -76.59,160.026 -76.59,160.268 -76.59,160.51 -76.59,160.752 -76.59,160.994 -76.59,161.236 -76.59,161.478 -76.59,161.72 -76.59,161.72 -76.811,161.72 -77.032,161.72 -77.253,161.72 -77.474,161.72 -77.695,161.72 -77.916,161.72 -78.137,161.72 -78.358,161.72 -78.579,161.72 -78.8,161.478 -78.8,161.236 -78.8,160.994 -78.8,160.752 -78.8,160.51 -78.8,160.268 -78.8,160.026 -78.8,159.784 -78.8,159.542 -78.8,159.3 -78.8,159.3 -78.579,159.3 -78.358,159.3 -78.137,159.3 -77.916,159.3 -77.695,159.3 -77.474,159.3 -77.253,159.3 -77.032,159.3 -76.811,159.3 -76.59))", "dataset_titles": "Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617; Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "datasets": [{"dataset_uid": "600045", "doi": "10.15784/600045", "keywords": "Allan Hills; Antarctica; Paleontology; Sample/Collection Description; Solid Earth", "people": "Miller, Molly", "repository": "USAP-DC", "science_program": "Allan Hills", "title": "Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600045"}, {"dataset_uid": "000124", "doi": "", "keywords": null, "people": null, "repository": "Burke Museum", "science_program": null, "title": "Burke Museum of Natural History and Culture, University of Washington ID#s UWBM 88593-88601, UWBM 88617", "url": "http://www.washington.edu/burkemuseum/collections/"}], "date_created": "Mon, 12 Oct 2009 00:00:00 GMT", "description": "This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate.\u003cbr/\u003e\u003cbr/\u003eIn terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.", "east": 161.72, "geometry": "POINT(160.51 -77.695)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.59, "nsf_funding_programs": "Antarctic Earth Sciences; Antarctic Earth Sciences; Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e PALEOZOIC \u003e CARBONIFEROUS \u003e PENNSYLVANIAN; PHANEROZOIC \u003e PALEOZOIC \u003e PERMIAN; PHANEROZOIC \u003e MESOZOIC \u003e TRIASSIC", "persons": "Miller, Molly; Sidor, Christian; Isbell, John", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "Other; USAP-DC", "science_programs": "Allan Hills", "south": -78.8, "title": "Collaborative Research: Reconstructing the High Latitude Permian-Triassic: Life, Landscapes, and Climate Recorded in the Allan Hills, South Victoria Land, Antarctica", "uid": "p0000207", "west": 159.3}, {"awards": "0124049 Berger, Glenn", "bounds_geometry": "POLYGON((161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.20000000000002 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.20000000000002 -77.5,163.4 -77.5,163.4 -77.52,163.4 -77.54,163.4 -77.56,163.4 -77.58,163.4 -77.6,163.4 -77.62,163.4 -77.64,163.4 -77.66,163.4 -77.68,163.4 -77.7,163.20000000000002 -77.7,163 -77.7,162.8 -77.7,162.6 -77.7,162.4 -77.7,162.20000000000002 -77.7,162 -77.7,161.8 -77.7,161.6 -77.7,161.4 -77.7,161.4 -77.68,161.4 -77.66,161.4 -77.64,161.4 -77.62,161.4 -77.6,161.4 -77.58,161.4 -77.56,161.4 -77.54,161.4 -77.52,161.4 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 25 Aug 2008 00:00:00 GMT", "description": "0124049\u003cbr/\u003eBerger\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.", "east": 163.4, "geometry": "POINT(162.4 -77.6)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e LIDAR/LASER SOUNDERS \u003e LASERS", "is_usap_dc": false, "keywords": "Dry Valleys; lake cores; luminescence geochronology; Antarctic lake-level; Stratigraphy; Climate Variability; shoreline deposits; Grain Size; Paleoclimate; Antarctica; LABORATORY", "locations": "Dry Valleys; Antarctica", "north": -77.5, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Berger, Glenn; Hall, Brenda; Doran, Peter", "platforms": "OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repositories": null, "science_programs": null, "south": -77.7, "title": "Collaborative Research: Millennial Scale Fluctuations of Dry Valleys Lakes: Implications for Regional Climate Variability and the Interhemispheric (a)Synchrony of Climate Change", "uid": "p0000219", "west": 161.4}, {"awards": "0230448 Severinghaus, Jeffrey; 0230260 Bender, Michael", "bounds_geometry": "POLYGON((-75.34 86.6,-68.742 86.6,-62.144 86.6,-55.546 86.6,-48.948 86.6,-42.35 86.6,-35.752 86.6,-29.154 86.6,-22.556 86.6,-15.958 86.6,-9.36 86.6,-9.36 83.618,-9.36 80.636,-9.36 77.654,-9.36 74.672,-9.36 71.69,-9.36 68.708,-9.36 65.726,-9.36 62.744,-9.36 59.762,-9.36 56.78,-15.958 56.78,-22.556 56.78,-29.154 56.78,-35.752 56.78,-42.35 56.78,-48.948 56.78,-55.546 56.78,-62.144 56.78,-68.742 56.78,-75.34 56.78,-75.34 59.762,-75.34 62.744,-75.34 65.726,-75.34 68.708,-75.34 71.69,-75.34 74.672,-75.34 77.654,-75.34 80.636,-75.34 83.618,-75.34 86.6))", "dataset_titles": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001; Trapped Gas Composition and Chronology of the Vostok Ice Core", "datasets": [{"dataset_uid": "609290", "doi": "10.7265/N5FJ2DQC", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochemistry; Glaciology; Paleoclimate; Siple Dome; Snow/Ice; South Pole", "people": "Battle, Mark; Severinghaus, Jeffrey P.; Bender, Michael", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Firn Air Inert Gas and Oxygen Observations from Siple Dome, 1996, and the South Pole, 2001", "url": "https://www.usap-dc.org/view/dataset/609290"}, {"dataset_uid": "609311", "doi": "10.7265/N5P26W12", "keywords": "Antarctica; Atmosphere; Chemistry:Fluid; Cryosphere; Geochronology; Glaciers/Ice Sheet; Ice Core Records; Lake Vostok; Paleoclimate; Vostok; Vostok Ice Core", "people": "Suwa, Makoto; Bender, Michael", "repository": "USAP-DC", "science_program": null, "title": "Trapped Gas Composition and Chronology of the Vostok Ice Core", "url": "https://www.usap-dc.org/view/dataset/609311"}], "date_created": "Wed, 18 Jan 2006 00:00:00 GMT", "description": "High latitude deep ice cores contain fundamental records of polar temperatures, atmospheric dust loads (and continental aridity), greenhouse gas concentrations, the status of the biosphere, and other essential properties of past environments. An accurate chronology for these records is needed if their significance is to be fully realized. The dating challenge has stimulated efforts at orbital tuning. In this approach, one varies a timescale, within allowable limits, to optimize the match between a paleoenvironmental property and a curve of insolation through time. The ideal property would vary with time due to direct insolation forcing. It would be unaffected by complex climate feedbacks and teleconnections, and it would give a clean record with high signal/noise ratio. It is argued strongly that the O2/N2 ratio of ice core trapped gases is such a property, and evidence is presented that this property, whose atmospheric ratio is nearly constant, is tied to local summertime insolation. This award will support a project to analyze the O2/N2 ratios at 1 kyr intervals from ~ 115-400 ka in the Vostok ice core. Ancillary measurements will be made of Ar/N2, and Ne/N2 and heavy noble gas ratios, in order to understand bubble close-off fractionation and its manifestation in the Vostok trapped gas record. O2/N2 variations will be matched with summertime insolation at Vostok to achieve a high-accuracy chronology for the Vostok core. The Vostok and other correlatable climate records will then be reexamined to improve our understanding of the dynamics of Pleistocene climate change.", "east": 106.8, "geometry": "POINT(106.8 -72.4667)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SAMPLERS \u003e BOTTLES/FLASKS/JARS \u003e FLASKS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Paleoclimate; Siple Dome; Ice Age; Trapped Gases; Not provided; Shallow Firn Air; LABORATORY; Vostok; Firn Air Isotopes; Firn Air Isotope Measurements; ice sample gas integrity; noble gases; Thermal Fractionation; Polar Firn Air; Ice Core Chemistry; Trapped Air Bubbles; Oxygen Isotopes; Ice Core; Antarctica; South Pole; Ice Core Data; GROUND-BASED OBSERVATIONS; Gas Age; Firn Isotopes; Ice Core Gas Records; Atmospheric Gases", "locations": "Antarctica; Vostok; Siple Dome; South Pole", "north": -72.4667, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Battle, Mark; Bender, Michael; Suwa, Makoto; Severinghaus, Jeffrey P.", "platforms": "Not provided; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -72.4667, "title": "Collaborative Research: Trapped Gas Composition and the Chronology of the Vostok Ice Core", "uid": "p0000257", "west": 106.8}, {"awards": "9527262 Gow, Anthony", "bounds_geometry": null, "dataset_titles": "Physical and Structural Properties of the Siple Dome Ice Cores", "datasets": [{"dataset_uid": "609128", "doi": "10.7265/N5668B34", "keywords": "Antarctica; Cryosphere; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Photo/Video; Siple Dome; Siple Dome Ice Core; WAISCORES", "people": "Gow, Tony; Meese, Deb", "repository": "USAP-DC", "science_program": "Siple Dome Ice Core", "title": "Physical and Structural Properties of the Siple Dome Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609128"}], "date_created": "Wed, 14 May 2003 00:00:00 GMT", "description": "This award is for support for a program to investigate the visual stratigraphy, index physical properties, relaxation characteristics and crystalline structure of ice cores from Siple Dome, West Antarctica. This investigation will include measurements of a time-priority nature that must be initiated at the drill site on freshly-drilled cores. This will be especially true of cores from the brittle ice zone, which is expected to comprise a significant fraction of the ice core. The brittle zone includes ice in which relaxation , resulting from the release of confining pressure is maximized and leads to significant changes in the mechanical condition of the core that must be considered in relation to the processing and analysis of ice samples for entrapped gas and chemical studies. This relaxation will be monitored via precision density measurements made initially at the drill site and repeated at intervals back in the U.S. Other studies will include measurement of the annual layering in the core to as great a depth as visual stratigraphy can be deciphered, crystal size measurements as a function of depth and age, c-axis fabric studies, and analysis of the physical properties of any debris-bearing basal ice and its relationship to the underlying bedrock. Only through careful documentation and analysis of these key properties can we hope to accurately assess the dynamic state of the ice and the age-depth relationships essential to deciphering the paleoclimate record at this location.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Chemical Composition; Siple Coast; volcanic deposits; Siple Dome; WAISCORES; Antarctica; Not provided; GROUND STATIONS; Stratigraphy; Ice Sheet; PICO; GROUND-BASED OBSERVATIONS; Ice Core; Density; Siple; NSIDC; Tephra; Fabric; Glaciology; Snow", "locations": "Antarctica; Siple Coast; Siple Dome", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Gow, Tony; Meese, Deb", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": null, "title": "Physical and Structural Properties of the Siple Dome Core", "uid": "p0000064", "west": null}]
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This is an international collaboration between the University of Colorado, the University of Kyoto, and the National Institute of Polar Research (NIPR) in Tokyo, to carry out a 40-day observational field campaign as part of the Japanese Antarctic Research Expedition (JARE) to Syowa station (690S, 400E) located on the eastern Antarctic coast. This campaign will deploy 44 custom high-altitude in-situ instruments called HYFLITS ('Hypersonic Flight in the Turbulent Stratosphere') to characterize turbulence in the troposphere and lower stratosphere, as well as conduct intercomparisons with the VHF PANSY radar (‘Program of the ANtarctic SYowa’) observations and concurrently deployed LODEWAVE (LOng-Duration balloon Experiment of gravity WAVE over Antarctica) observations.
This research is motivated by the fact that the sources representing realistic multi-scale gravity wave (GW) drag, and Kelvin Helmholtz Instability (KHI) dynamics in enhanced shear flows, and their contributions to momentum/energy budgets due to turbulent transport/mixing, are largely missing in the current state-of-the-art General Circulation Model (GCM) parameterization schemes. This results in poor and unreliable model forecasts of flow features from local to synoptic scales at southern high latitudes.
The proposed research aims to utilize high-resolution in-situ turbulence instruments to characterize the multi-scale GW sources and breaking, KHI instabilities emerging in a wide range of scales, Reynolds and Richardson numbers, and background GW environments in the coastal Antarctic region and quantify their contributions to the momentum and turbulence energy budgets in the tropo-stratosphere. Specific research objectives include the following:
1. Characterize the large-scale dynamics of orographic GWs produced by katabatic forcing and non-orographic GWs produced by summer tropopause jets and low-pressure synoptic-scale events employing targeted HYFLITS and LODEWAVE measurements in conjunction with PANSY radar observations.
2. Quantify the GW momentum fluxes using HYFLITS and LODEWAVE measurements, and the turbulence dissipation rates using HYFLITS and PANSY radar measurements for representative multi-scale GW and KHI events to assess the zonal and meridional energy and constituent transport, and the variability in turbulence intensities/mixing throughout the troposphere and lower stratosphere.
The project will deploy the low-cost HYFLITS systems equipped with custom in-situ turbulence and radiosonde instruments at Syowa station. These balloon payloads descend slowly from an apogee of 20 km to provide high-resolution, wake-free turbulence observations, with guidance from real-time PANSY radar echoes and in coordination with the LODEWAVE experiment, to profile the atmospheric states for representative dynamical events.
Arrigo, Kevin; Thomas, Leif N; Baumberger, Tamara; Resing, Joseph
No dataset link provided
Part 1.
Phytoplankton blooms throughout the world support critical marine ecosystems and help remove harmful CO2 from the atmosphere. Traditionally, it has been assumed that phytoplankton blooms in the Southern Ocean are stimulated by iron from either the continental margin or sea-ice. However, recent work demonstrates that hydrothermal vents may be an additional iron source for phytoplankton blooms. This enhancement of phytoplankton productivity by different iron sources supports rich marine ecosystems and leads to the sequestration of C in the deep ocean. Our proposed work will uncover the importance of hydrothermal activity in stimulating a large phytoplankton blooms along the southern boundary of the Antarctic Circumpolar Current just north of the Ross Sea. It will also lead towards a better understanding of the overall impact of hydrothermal activity on the C cycle in the Southern Ocean, which appears to trigger local hotspots of enhanced biological activity which are a potential as a sink for atmospheric CO2. This project will encourage the participation of underrepresented groups in ocean sciences, as well as providing educational opportunities for high school and undergraduate students, through three different programs. Stanford University’s Summer Undergraduate Research in Geoscience and Engineering (SURGE) program provides undergraduates from different US universities and diverse cultural backgrounds the opportunity to spend a summer doing a research project at Stanford. The Stanford Earth Summer Undergraduate Research Program (SESUR) is for Stanford undergraduates who want to learn more about environmental science by performing original research. Finally, Stanford’s School of Earth, Energy, and Environmental Sciences High School Internship Program enables young scientists to serve as mentors, prepares high school students for college, and serves to strengthen the partnership between Stanford and local schools. Students present their results at the Fall AGU meeting as part of the AGU Bright STaRS program. This project will form the basis of at least two Ph.D. dissertations. The Stanford student will participate in Stanford’s Woods Institute Rising Environmental Leaders Program (RELP), a year-round program that helps graduate students hone their leadership and communication skills to maximize the impact of their research. The graduate student will also participate in Stanford’s Grant Writing Academy where they will receive training in developing and articulating research strategies to tackle important scientific questions.
Part 2.
This interdisciplinary program combines satellite and ship-based measurements of a large poorly understood phytoplankton bloom (the AAR bloom) in the northwestern Ross Sea sector of the Southern Ocean with a detailed modeling study of the physical processes linking deep dissolved iron (DFe) reservoirs to the surface phytoplankton bloom. Prior to the cruise, we will implement a numerical model (CROCO) for our study region so that we can better understand the circulation, plumes, turbulence, fronts, and eddy field around the AAR bloom and how they transport and mix hydrothermally produced DFe vertically. Post cruise, observations of the vertical distribution of 3He (combined with DMn and DFe), will be used as initial conditions for a passive tracer in the model, and tracer dispersal will be assessed to better quantify the role of the various turbulent processes in upwelling DFe-rich waters to the upper ocean. The satellite-based component of the program will characterize the broader sampling region before, during, and after our cruise. During the cruise, our automated software system at Stanford University will download and process images of sea ice concentration, Chl a concentration, sea surface temperature (SST), and SSH and send them electronically to the ship. Operationally, our goal is to use all available satellite data and preliminary model results to target shipboard sampling both geographically and temporally to optimize sampling of the AAR bloom. We will use available BGC-Argo float data to help characterize the AAR bloom. In collaboration with SOCCOM, we will deploy additional BGC-Argo floats (if available) during our transit through the study area to allow us to better characterize the bloom. The centerpiece of our program will be a 40-day process study cruise in austral summer. The cruise will consist of an initial “radiator” pattern of hydrographic surveys/sections along the AAR followed by CTDs to selected submarine volcanoes. When/if eddies are identified, they will be sampled either during or after the initial surveys. The radiator pattern, or parts thereof, will be repeated 2-3 times. Hydrographic survey stations will include vertical profiles of temperature, salinity, oxygen, oxidation-reduction potential, light scatter, and PAR (400-700 nm). Samples will be collected for trace metals, ligands, 3He, and total suspended matter. Where intense hydrothermal activity is identified, samples for pH and total CO2 will also be collected to characterize the hydrothermal system. Water samples will be collected for characterization of macronutrients, and phytoplankton physiology, abundance, species composition, and size. During transits, we will continuously measure atmospheric conditions, current speed and direction, and surface SST, salinity, pCO2, and fluorescence from the ship’s systems to provide detailed maps of these parameters. The ship will be used as a platform for conducting phytoplankton DFe bioassay experiments at key stations throughout the study region both inside and outside the bloom. We will also perform detailed comparisons of algal taxonomic composition, physiology, and size structure inside and outside the bloom to determine the potential importance of each community on local biogeochemistry.
Magnetic field variations on the Earth’s surface can be used to remote sense and characterize electrical currents and plasma waves in the near-Earth space environment that can affect technology, for example by inducing currents in power grids. Asymmetries between the space environment in the polar regions of the northern and southern hemispheres can profoundly affect these magnetic field variations. Magnetometers, which measure the strength and direction of magnetic fields, have been installed in the Arctic and Antarctic at opposite ends of the Earth’s magnetic field lines. By looking at data from both sets of magnetometers, researchers can determine whether disturbances in the Earth’s magnetosphere (a region of near-Earth space dominated by the Earth’s magnetic field) caused by the Sun impact the Northern hemisphere, the Southern hemisphere or both, and thus understand the sources of north-south hemisphere asymmetries. Some events that appear in the magnetometer data may be difficult for computers to identify, but easy for people to identify if the data is translated into sound. Researchers will develop a tool for listening to data in a virtual reality environment, so that data from various instruments can be played back, making it easier to explore datasets intuitively. This system will be prototyped using a mixed reality headset for use in both science and education and may be used to analyze data taken at the same time by sensors on the ground and on satellites.
This project will examine one particular type of disturbance – magnetosheath jets – and its relation to plasma waves by addressing the question “Do magnetosheath jets routinely drive Pc5/Pc6 geomagnetic pulsations?” via the analysis of magnetometer data from geomagnetically conjugate (based on the International Geomagnetic Reference Field, IGRF) Arctic and Antarctic magnetometers. This question will be approached first through traditional plotting and visual analysis, then by presenting datastreams as sound sources situated in a virtual audio environment developed in the Unity game engine and integrated with mixed reality presentation via the Microsoft Hololens platform. This approach will leverage human capabilities for spatial discrimination of sounds to identify geomagnetic pulsations (surface magnetic field variations related to plasma waves in outer space) related to magnetosheath jet events with potentially large north-south hemispheric asymmetries, spatially localized wave activity, and irregular waveforms. The resulting presentation modality will make use of existing repositories of magnetometer data and may potentially be extended to the presentation of synchronous datasets from multiple sensing networks.
Traditional models of oceanic food chains have consisted of photosynthetic algae (phytoplankton) being ingested by small animals (zooplankton), which were ingested by larger animals (fish). These traditional models changed as new methods allowed recognition of the importance of bacteria and other non-photosynthetic protozoa in more complex food webs. More recently, the wide-spread existence of mixotrophs (organisms that can both photosynthesize and ingest food particles) and their importance as microbial predators has been recognized in many oceanographic areas. In the Southern Ocean, the only two surveys of mixotrophs have suggested that there may be seasonal differences in their importance as predators. During the long polar night (winter), the ability of mixotrophs to ingest particulate food may aid in their survival thus ensuring a sufficient population in spring to support a phytoplankton bloom once photosynthesis rates can increase. Thus mixotrophs may provide a critical early food source upon which zooplankton and larger animals depend on for growth and reproduction. This project will advance understanding of mixotroph diversity and their ecological impact within the Southern Ocean microbial food web. Specifically, efforts will be focused on mixotrophy in the western Antarctica peninsula region during the austral spring and autumn when there are likely to be changes in the relative importance of photosynthesis and ingestion to mixotrophs. The project will provide research opportunities for undergraduate and graduate students and a post-doctoral researcher. There will be real-time outreach from the Southern Ocean to the public via blogs and interviews, and to high school art students through an established program that blends science and art education. Despite traditional views of protists as either "phototrophic" or "heterotrophic," there are many photosynthetic protists that consume prey (mixotrophy). Mixotrophy is a widespread phenomenon in aquatic systems and phytoplankton groups with known mixotrophic species, notably chrysophytes, cryptophytes, prymnesiophytes, prasinophytes and dinoflagellates, are present and often abundant in Antarctic waters. However, in the Southern Ocean, the presence of mixotrophic phytoflagellates has been surveyed only twice prior to this project: in the Ross Sea during Austral spring 2008 and summer 2011. The primary goals of the project are to gain better understanding of mixotroph diversity and their ecological impact with respect to the Southern Ocean microbial food web. The contribution of mixotrophs to primary production and bacterial consumption is likely linked to the taxonomic composition of the community and the abundance of particular species. Abundances of novel mixotrophic species will be evaluated via qPCR, which will be coupled with assessments of rates of feeding and photosynthesis with the goal of describing how active mixotrophs direct the movement of carbon through food webs. These experiments will help the determination of how viable and widespread mixotrophy is as a nutritional strategy in polar waters and give direct information on the currently unknown diversity of mixotrophic taxa under different environmental conditions occurring in austral spring and autumn. Furthermore, the methods will simultaneously yield information on the whole communities of protists - mixotrophic, phototrophic and heterotrophic. In addition, a method to examine aspects of the taxonomic and functional diversities of the bacterivorous/mixotrophic community will be employed. A thymidine analog (BrdU) will be used to label DNA of eukaryotes feeding on bacteria. The BrdU-labeled eukaryotic DNA will be isolated using immunoprecipitation. High-throughput sequencing of the labeled DNA (bacterivores) versus unlabeled community DNA will determine the diversity of bacterivorous mixotrophs relative to other microeukaryotes. Flow cytometric sorting based on chlorophyll to focus on mixotrophic species. These approaches will elucidate a gap in current knowledge of the influence of microbial interactions in the Southern Ocean under different conditions. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
Overview: Several recent studies indicate continuing and increasing ice loss from the Amundsen Sea region of West Antarctica (chiefly Pine Island and Thwaites glaciers). This loss is initiated by thinning of the floating ice shelves by basal melting driven by circulation of relatively warm ocean water under the ice shelves. This thinning triggers ice-dynamics related feedbacks, which leads to loss of ice from the grounded ice sheet. Models suggest that, even though long-term committed ice loss might be governed by ice dynamics, the magnitude of ocean-driven melting at the base of the ice shelves plays a critical role in controlling the rate of ice loss. These conclusions, however, are based on simple parameterized models for melt rate that do not take into account how ocean circulation will change in future as large-scale climate forcing changes, and as the ice shelves thin and retreat through both excess melting and accelerated ice flow. Given that present global climate models struggle to resolve the modern ocean state close to the ice shelves around Antarctica, their projections of future impacts on basal melting and time scale of ice loss have large uncertainties.
This project is aimed at reducing these uncertainties though two approaches: (i) assessing, for a given ocean state, how the melt rates will change as ice-shelf cavities evolve through melting and grounding-line retreat, and (ii) improving understanding of the sensitivity of melt rates beneath the Pine Island and Thwaites ice shelves to changes in ocean state on the Amundsen Sea continental shelf. These studies will provide more realistic bounds on ice loss and sea level rise, and lay the groundwork for development of future fully-coupled ice sheet-ocean simulations.
Intellectual Merit: Rather than pursue a strategy of using fully coupled models, this project adopts a simpler semi-coupled approach to understand the sensitivity of ice-shelf melting to future forcing. Specifically, the project focuses on using regional ocean circulation models to understand current and future patterns of melting in ice-shelf cavities. The project’s preliminary stage will focus on developing high-resolution ice-shelf cavity-circulation models driven by modern observed regional ocean state and validated with current patterns of melt inferred from satellite observations. Next, an ice-flow model will be used to estimate the future grounding line at various stages of retreat. Using these results, an iterative process with the ocean-circulation and ice-flow models will be applied to determine melt rates at each stage of grounding line retreat. These results will help assess whether more physically constrained melt-rate estimates substantially alter the hypothesis that unstable collapse of the Amundsen Sea sector of West Antarctica is underway. Further, by multiple simulations with modified open-ocean boundary conditions, this study will provide a better understanding of the sensitivity of melt to future changes in regional forcing. For example, what is the sensitivity of melt to changes in Circumpolar Deep Water temperature and to changes in the thermocline height driven be changes in wind forcing? Finally, several semi-coupled ice-ocean simulations will be used to investigate the influence of the ocean-circulation driven distribution of melt over the next several decades. These simulations will provide a much-improved understanding of the linkages between far-field ocean forcing, cavity circulation and melting, and ice-sheet response.
Broader Impacts: Planning within the current large range of uncertainty in future sea level change leads to high social and economic costs for governments and businesses worldwide. Thus, our project to reduce sea-level rise uncertainty has strong societal as well as scientific interest. The findings and methods will be applicable to ice shelf cavities in other parts of Antarctica and northern Greenland, and will set the stage for future studies with fully coupled models as computational resources improve. This interdisciplinary work combines expertise of glaciologists and oceanographers, and will contribute to the education of new researchers in this field, with participation of graduate students and postdocs. Through several outreach activities, team members will help make the public aware of the dramatic changes occurring in Antarctica along with the likely consequences.
This proposal does not require fieldwork in the Antarctic.
The Weddell Gyre is one of the major components of the Southern Ocean circulation system, linking heat and carbon fluxes in the Antarctic Circumpolar Current to the continental margins. Water masses entering the Weddell Gyre are modified as they move in a great circular route around the gyre margin and change through processes involving air-sea-cryosphere interactions as well as through ocean eddies that mix properties across the gyre boundaries. Some of the denser water masses exit the gyre through pathways along the northern boundary, and ultimately ventilate the global deep ocean as Antarctic Bottom Water. While in-situ and satellite observations, as well as computer modeling efforts, provide estimates of the large-scale average flow within the gyre, details of the smaller-scale, or "mesoscale" eddy flow remain elusive. The proposed research will quantify mixing due to mesoscale eddies within the Weddell Gyre, as well as the transport of incoming deep water from the northeast, thought to be a result of transient eddies. Since the Weddell Gyre produces source water for about 40% of Antarctic Bottom Water formation, understanding the dynamics in this region helps to identify causes of documented changes in global bottom waters. This in turn, will give insight into how climate change is affecting global oceans, through modification of dense polar waters and Antarctic Bottom Water characteristics.
This project aims to track 153 RAFOS-enabled Argo floats in the ice-covered regions of the Weddell Gyre. The resultant tracks along with all available Argo and earlier float data will be used to calculate Eulerian and Lagrangian means and eddy statistics for the Weddell Gyre. The study will link RAFOS tracks with Argo profiles under ice, allowing one to characterize the importance of eddies in water column modification at critical ice-edge boundaries and leads. With RAFOS tracks near the northeastern limit of the gyre, the project will investigate the eddy-driven processes of incoming Circumpolar Deep Water, to understand better the mechanisms and volume fluxes involved. Previous work shows that a large fraction of the mean circulation in the southern and western limits of the gyre, where it contacts the Antarctic continent, occurs in a narrow boundary layer above the slope. The research here will integrate this flow structure into a complete interior and boundary layer mean circulation synthesis. The findings and products from the proposed work will improve the positioning of Argo profiles in the polar regions, which would allow for more accurate climatological maps and derived quantities. Estimates of meso-scale mixing may serve as a foundation for the development of new parameterization schemes employed in climate models, as well as local and global ocean circulation models in polar regions.
Isotopic and sedimentary datasets reveal that volcanic activity typically increases during interglacial periods. However, the physical mechanisms through which changes in the surface loading affect volcanic magmatic plumbing systems remain unconstrained. Recently generated 40Ar/39Ar eruption ages indicate that 86% of the dated samples from Mt. Waesche, a late Quaternary volcano in Marie Byrd land, correlate with interglacial periods, suggesting this volcano uniquely responds to changes in the West Antarctic Ice Sheet. We propose to combine the petrology of Mount Waesche’s volcanic record, constraints on changing ice loads through time, and geodynamic modelling to: (1) Determine how pre-eruptive storage conditions change during glacial and interglacial periods using whole rock and mineral compositions of volcanic rocks; (2) Conduct geodynamic modeling to elucidate the relationship between lithospheric structure, temporal variations in ice sheet thickness, and subsequent changes in crustal stresses and magmatic transport and, therefore, the mechanism(s) by which deglaciation impacts magmatic plumbing systems; (3) Use the outcomes of objectives (1) and (2) to provide new constraints on the changes in ice sheet thickness through time that could plausibly trigger future volcanic and magmatic activity in West Antarctica. This collaborative approach will provide a novel methodology to determine prior magnitudes and rates of ice load changes within the Marie Byrd Land region of Antarctica. Lastly, estimates of WAIS elevation changes from this study will be compared to ongoing studies at Mount Waesche focused on constraining last interglacial ice sheet draw down using cosmogenic exposure ages obtained from shallow drilling. The scope of work also includes a partnership with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online.
Overview:
Antarctic biota face increasing stressors from warming oceans. A key question is: What will be the effect of warming waters on Antarctic biota? A gap in our knowledge is the identify of early harbingers of new stressors. In our recent field season, we unexpectedly discovered pink, wart-like neoplasms in Antarctic notothenioid fish, including Trematomus scotti (crowned notothen) and Nototheniops larseni (painted notothen). Neoplasms affected about 30% of T. scotti collected in Andvord Bay on the West Antarctic Peninsula and covered 10 to 30% of the bodies of affected individuals, usually in one contiguous patch. We collected samples from affected and apparently unaffected controls. We could not find evidence of any similar outbreak. Our overall goal is to learn the biological origins of this neoplasm and how it affects cellular function and organismal physiology.
Intellectual Merit:
Aim 1: Pathogenic agents. Aim 1a: To test the hypothesis that a virus causes the neoplasm. Methods involve isolating and sequencing viral nucleic acids from neoplasms and from unaffected skin and comparing sequences to known viruses. Aim 1b: To test the hypothesis that neoplasms are hosts to parasites not present in healthy skin. Methods include tissue sections and DNA sequencing to find evidence of parasitic organisms. Significance: achieving Aim 1 will narrow down possible etiological agents. An untested possibility is that environmental contaminants cause the condition; exploring that hypothesis would require further sampling outside the limits of an EAGER proposal.
Aim 2: Cell-level pathology. Aim 2a: To test the hypothesis that the histopathology of the neoplasms is similar to other known skin neoplasias; alternatively, it might be a previously unknown type of neoplasia. Methods involve the examination of histological sections to identify pathology-specific characters. Aim 2b: To find effects of neoplasms on cell function. Methods involve performing whole-genome transcriptomics of affected and normal skin by RNA-seq and aligning reads to a T. scotti reference genome. Significance: achieving Aim 2 will define the cell biology and gene-expression phenotypes of the neoplasia, thus suggesting mechanisms that cause it.
[Note: NSF deleted funds specifically to achieve the Aim 3, which nevertheless appears here to represent the original proposal.] Aim 3: Organismal pathology. Aim 3a: To test the hypothesis that the neoplasm has adverse effects on growth and physiology. Methods are to perform morphometrics in fish with neoplasms compared to age-matched controls from otolith studies. Aim 3b: To test the hypothesis that the neoplasia affects reproductive traits. Methods compare reproductive effort in affected and unaffected individuals. Significance: if the neoplasia has little consequences on growth and reproduction, our worry about its spread will be lessened, but if it is harmful, then Antarctic ecology, which largely depends on notothenioid fish, might be in danger.
Achieving Aims 1-3 will advance knowledge by identifying the causes of a neoplasia outbreak in Antarctic fish. Work is potentially transformative because it might represent an early sign of Antarctic fish responses to the stress of global climate change. Proposed work would be the first to investigate a neoplasia outbreak in Antarctic fish. We will assess the project’s success by whether we identify a causative agent and its effects on physiology.
Broader Impacts:
Aim 4: Publicizing the neoplasia. We aim to raise awareness of the outbreak and publicize its distinct diagnostic features, including assays to detect it, by contributing to groups that track Antarctic ecosystems.
Aim 5: Inclusion. We will involve underrepresented groups in scientific research with authentic research experiences.
Achieving Aims 4 and 5 will benefit society because they will disseminate to scientific and lay communities a potential early-warning system for the effects of an apparently new neoplasia affecting, at least locally, a large proportion of a fish population. Dissemination will stir research to determine whether this neoplasia outbreak is an isolated event or is becoming a general phenomenon, and thus a concern for Antarctic ecosystems. Proposed research will enhance research infrastructure by providing tools to identify the neoplasia. Finally, the project will broaden access to research careers by exposing underserved high school students and undergraduates to an exciting live research project.
As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high "weatherability" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth's carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential "weather ability" and investigate how sediment produced in these glacial systems could ultimately impact Earth's carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.
Physical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.
Coastal waters surrounding Antarctica represent some of the most biologically rich and most untouched ecosystems on Earth. In large part, this biological richness is concentrated within the numerous openings that riddle the expansive sea ice (these openings are known as polynyas) near the Antarctic continent. These polynyas represent regions of enhanced production known as hot-spots and support the highest animal densities in the Southern Ocean. Many of them are also located adjacent to floating extensions of the vast Antarctic Ice Sheet and receive a substantial amount of meltwater runoff each year during the summer. However, little is known about the specific processes that make these ecosystems so biologically productive. Of the 46 Antarctic coastal polynyas that are presently known, only a handful have been investigated in detail.
This project will develop ecosystem models for the Ross Sea polynya, Amundsen polynya, and Pine Island polynya; three of the most productive Antarctic coastal polynyas. The primary goal is to use these models to better understand the fundamental physical, chemical, and biological interacting processes and differences in these processes that make these systems so biologically productive yet different in some respects (e.g. size and productivity) during the present day settings. Modeling efforts will also be extended to potentially assess how these ecosystems may have functioned in the past and how they might change in the future under different physical and chemical and climatic settings.
The project will advance the education of underrepresented minorities through Stanford?s Summer Undergraduate Research in Geoscience and Engineering (SURGE) Program. SURGE will provide undergraduates the opportunity to gain mentored research experiences at Stanford University in engineering and the geosciences. Old Dominion University also will utilize an outreach programs for local public and private schools as well as an ongoing program supporting the Boy Scout Oceanography merit badge program to create outreach and education impacts.
Polynyas (areas of open water surrounded by sea ice) are disproportionately productive regions of polar ecosystems, yet controls on their high rates of production are not well understood. This project will provide quantitative assessments of the physical and chemical processes that control phytoplankton abundance and productivity within polynyas, how these differ for different polynyas, and how polynyas may change in the future. Of particular interest are the interactions among processes within the polynyas and the summertime melting of nearby ice sheets, including the Thwaites and Pine Island glaciers.
In this proposed study, we will develop a set of comprehensive, high resolution coupled physical-biological models and implement these for three major, but diverse, Antarctic polynyas. These polynyas, the Ross Sea polynya, the Amundsen polynya, and Pine Island polynya, account for >50% of the total Antarctic polynya production.
The research questions to be addressed are: 1) What environmental factors exert the greatest control of primary production in polynyas around Antarctica? 2) What are the controlling physics that leads to the heterogeneity of dissolved iron (dFe) supply to the euphotic zone in polynyas around the Antarctic continental shelf? What effect does this have on local rates of primary production? 3) What are the likely changes in the supply of dFe to the euphotic zone in the next several decades due to climate-induced changes in the physics (winds, sea-ice, ice shelf basal melt, cross-shelf exchange, stratification and vertical mixing) and how will this affect primary productivity around the continent?
The Ross Sea, Amundsen, and Pine Island polynyas are some of the best-sampled polynyas in Antarctica, facilitating model parameterization and validation. Furthermore, these polynyas differ widely in their size, location, sea ice dynamics, relationship to melting ice shelves, and distance from the continental shelf break, making them ideal case studies. For comparison, the western Antarctic Peninsula (wAP), a productive continental shelf where polynyas are a relatively minor contributor to biological production, will also be modeled. Investigating specific processes within different types Antarctic coastal waters will provide a better understand of how these important biological oases function and how they might change under different environmental conditions.
The Southern Ocean in the vicinity of Antarctica is a region characterized by seasonally-driven marine phytoplankton blooms that are often dominated by microalgal species which produce large amounts of dimethylsulfoniopropionate (DMSP). DMSP can be converted to the compound dimethylsulfide (DMS) which is a molecule that can escape into the atmosphere where it is known to have strong condensation properties that are involved in regional cloud formation. Production of DMSP can influence the diversity and composition of microbial assemblages in seawater and the types and activities of microbes in the seawater will likely affect the magnitude of DMSP\DMS production. The project examined the role of DMSP in structuring the microbial communities in Antarctic waters and how this structuring may influence DMSP cycling. The project interacted with elementary students in Maine and brought undergraduate students to Bigelow Laboratory. The project also engaged with a science writer and illustrator who joined the team in Palmer Station in 2018. Many posts are available at xxx
The project is examining (1) the extent to which the cycling of DMSP in southern ocean waters influenced the composition and diversity of bacterial and protistan assemblages; (2) conversely, whether the composition and diversity of southern ocean protistan and bacterial assemblages influenced the magnitude and rates of DMSP cycling; we are awaiting results on (3) the expression of DMSP degradation genes by marine bacteria seasonally and in response to field experimental additions of DMSP; and, this year (2020-21), we will synthesize these results by quantifying (4) the microbial networks resulting from the presence of DMSP-producers and DMSP-consumers along with their predators, all involved in the cycling of DMSP in southern ocean waters. The work was accomplished by conducting continuous growth experiments with DMSP-amended natural samples of different microbial communities present in summer (2016-17) and fall (2018) at Palmer Station, WAP. Data from the molecular (such as 16S/ 18S tag sequences, DMSP-cycle gene transcripts) and biogeochemical (such as biogenic sulfur cycling, bacterial production, microbial biomass) investigations will be integrated via network analysis in the coming year (2020-21).
The depletion of stratospheric ozone over Antarctica leads to abnormally high levels of ultraviolet radiation (UVR) from the sun reaching the surface of the ocean. This phenomenon is predicted to continue for the next half century, despite bans on ozone-destroying pollutants. Phytoplankton in the near surface ocean are subjected to variable amounts of UVR and contain a lot of lipids (fats). Because phytoplankton are at the base of the food chain their lipids makes their way into the Antarctic marine ecosystem's food web. The molecular structures of phytoplankton lipids are easily altered by UVR. When this happens, their lipids can be transformed from healthy molecules into potentially harmful molecules(oxylipins) known to be disruptive to reproductive and developmental processes. This project will use state-of-the-art molecular methods to answer questions about extent to which UVR damages lipid molecules in phytoplankton, and how these resultant molecules might effect the food chain in the ocean near Antarctica. <br/><br/><br/>Lipid peroxidation is often invoked as consequence of increased exposure of phytoplankton to UVR-produced reactive oxygen species (ROS), but the literature is practically silent on peroxidized lipids and their byproducts (i.e. oxylipins) in the ocean. In waters of the West Antarctic Peninsula (WAP), spring-time blooms of diatoms contribute significantly to overall marine primary production. Oxylipins from diatoms can be highly bioactive; their impact on zooplankton grazers, bacteria, and other phytoplankton has been the subject of intense study. However, almost all of this work has focused on the production of oxylipins via enzymatic pathways, not by pathways involving UVR and/or ROS. Furthermore, rigorous experimental work on the effects of oxylipins has been confined almost exclusively to pure cultures and artificial communities. Thus, the true potential of these molecules to disrupt carbon cycling is very poorly-constrained, and is entirely unknown in the waters of the WAP. Armed with new highly-sensitive, state-of-the-art analytical techniques based on high-mass-resolution mass spectrometry, the principal investigator and his research group have begun to uncover an exquisite diversity of oxylipins in natural WAP planktonic communities. These techniques will be applied to understand the connections between UVR, ROS, oxylipins, and carbon cycling. The project will answer the question of how UVR, via ROS, affects oxylipin production by diatoms in WAP surface waters in controlled experiments conducted at a field station. With the answer to this question in hand, the project will also seek to answer how this phenomenon impacts the flow of carbon, particularly the export of organic carbon from the system, during a research cruise. The level of UVR-induced stresses experienced by oxylipin-rich planktonic communities in the WAP is unique, making Antarctica the only location for answering these fundamental questions. Major activities will include laboratory experiments with artificial membranes and diatom cultures, as well field experiments with phytoplankton, zooplankton, and bacteria in WAP waters.
Polar regions are deserts that are not only cold but also lack access to free water. Antarctic insects have unique survival mechanisms including the ability to tolerate freezing and extensive dehydration, surviving the loss of 70% of their body water. How this is done is of interest not only for understanding seasonal adaptations of insects and how they respond to climate change, but the molecular and physiological mechanisms employed may offer valuable insights into more general mechanisms that might be exploited for cryopreservation and long-term storage of human tissues and organs for transplantation and other medical applications. The investigators will study the proteins that are responsible for removing water from the body, cell level consequences of this, and how the responsible genes vary between populations. The project will also further the NSF goals of making scientific discoveries available to the general public and of training new generations of scientists. Each year a K-12 teacher will be a member of the field team and assist with fieldwork and outreach to school children and their teachers. Educational outreach efforts include presentations at local schools and national teacher meetings, providing lesson plans and podcasts on a website, and continuing to publish articles related to this research in education journals. In addition, undergraduate and graduate students will receive extensive training in all aspects of the research project with extended experiences that include publication of scientific papers and presentations at national meetings.<br/><br/>This project focuses on deciphering the physiological and molecular mechanisms that enable the Antarctic midge Belgica antarctica to survive environmental stress and the loss of most of its body water in the desiccating polar environment. This extremophile is an ideal system for investigating mechanisms of stress tolerance and local geographic adaptations and its genome has recently been sequenced. This project has three focal areas: 1) Evaluating the role of aquaporins (water channel proteins) in the rapid removal of water from the body by studying expression of their genes during dehydration; 2) Investigating the mechanism of metabolic depression and the role of autophagy (controlled breakdown of cellular components) as a mediator of stress tolerance by studying expression of the genes responsible for autophagy during the dehydration process; and 3) Evaluating the population structure, gene flow, and adaptive variation in physiological traits associated with stress tolerance using a genetic approach that takes advantage of the genomic sequence available for this species coupled with physiological and environmental data from the sampled populations and their habitats.
Since the advent of Antarctic continental glaciation, the opening of the Drake Passage between South America and the Antarctic Peninsula, and the onset of cooling of the Southern Ocean ~40-25 million years ago, evolution of the Antarctic marine biota has been driven by the development of extreme cold temperatures. As circum-Antarctic coastal temperatures declined during this period from ~20°C to the modern -1.9 to +2.0°C (reached ~8-10 million years ago), the psychrophilic (cold-loving) ectotherms of the Southern Ocean evolved compensatory molecular, cellular, and physiological traits that enabled them to maintain normal metabolic function at cold temperatures. Today, these organisms are threatened by rapid warming of the Southern Ocean over periods measured in centuries (as much as 5°C/100 yr), a timeframe so short that re-adaptation and/or acclimatization to the "new warm" may not be possible. Thus, the long-term goals of this research project are: 1) to understand the biochemical and physiological capacities of the embryos of Antarctic notothenioid fish to resist or compensate for rapid oceanic warming; and 2) to assess the genetic toolkit available to support the acclimatization and adaptation of Antarctic notothenioid embryos to their warming habitat. The specific aims of this work are: 1) to determine the capacity of the chaperonin complex of notothenioid fishes to assist protein folding at temperatures between -4 and +20°C; and 2) to evaluate the genetic responses of notothenioid embryos, measured as global differential gene transcription, to temperature challenge, with -1.9°C as the "normal" control and +4 and +10°C as high temperature insults.
The physiology of embryonic development of marine stenotherms under future climate change scenarios is an important but understudied problem. This project will provide valuable insights into the capacity of Antarctic fish embryos to acclimatize and adapt to plausible climate change scenarios by examining multiple levels of biological organization, from the biochemical to the organismal. The results should also be broadly applicable to understanding the impact of global warming on marine biota worldwide. The research will also introduce graduate and undergraduate students to state-of-the-art biochemical, cellular, and molecular-biological research relevant to ecological and environmental issues of the Antarctic marine ecosystem.
Ice shelves are the floating portions of glaciers that terminate in the ocean. They are common around the periphery of Antarctica. The accumulation of surface meltwater on or near the surface of ice shelves can play a role in ice-shelf collapse, which leads to accelerated loss of grounded ice and sea-level rise. Recent studies have showed that present-day meltwater generation and movement across the surface of Antarctica is more widespread than previously thought and is expected to increase. Consequently, there is a growing need to address the role of surface water in forecasts of ice-shelf behavior. While much progress has been made, understanding of the role of water in ice-shelf collapse is still in its infancy. This award supports a workshop that will bring together experts from multiple disciplines that, together, can advance understanding of Antarctic surface hydrology and its role in the future stability of ice shelves. This workshop will bring together U.S. and international scientists with expertise in ice-sheet dynamics, glacial hydrology, climatology, and other disciplines to identify critical knowledge gaps and move the community towards answering fundamental questions such as: What climate dynamics are responsible for surface meltwater generation in Antarctica? What controls the spatiotemporal distribution of meltwater ponds on Antarctic ice shelves? Where is meltwater generated, where does it pond today, and how will this change this century? How will meltwater impact ice shelves? How will surface hydrology impact sea-level this century? The deliberations will be captured in a workshop report.
This award supports an integrated field observation, remote sensing and numerical modeling study of the McMurdo Shear Zone (SZ). The SZ is a 5-10 km wide strip of heavily crevassed ice that separates the McMurdo and Ross ice shelves, and is an important region of lateral support for the Ross Ice Shelf. Previous radar and remote sensing studies reveal an enigmatic picture of the SZ in which crevasses detected at depth have no apparent surface expression, and have orientations which are possibly inconsistent with the observed flow field. In the proposed work, we seek to test the hypothesis that the SZ is a zone of chaotic Lagrangian mixing with (intersecting) buried crevasses which leads to rheological instability, potentially allowing large scale velocity discontinuities. The work will involve detailed field-based observations of crevasse distributions and structure using ground-penetrating radar, and GPS and remote sensing observations of the flow and stress field in the SZ. Because of the hazardous nature of the SZ, the radar surveys will be conducted largely with the aid of a lightweight robotic vehicle. Observations will be used to develop a finite element model of ice shelf shear margin behavior. The intellectual merit of this project is an increased understanding of ice shelf shear margin dynamics. Shear margins play a key role in ice shelf stability, and ice shelves in turn modulate the flux of ice from the ice sheet across the grounding line to the ocean. Insights from this project will improve large-scale models being developed to predict ice sheet evolution and future rates of sea level rise, which are topics of enormous societal concern. The broader impacts of the project include an improved basis for US Antarctic Program logistics planning as well as numerous opportunities to engage K-12 students in scientific discovery. Intensified crevassing in the shear zone between the Ross and McMurdo ice shelves would preclude surface crossing by heavy traverse vehicles which would lead to increased costs of delivering fuel to South Pole and a concomitant loss of flight time provided by heavy-lift aircraft for science missions on the continent. Our multidisciplinary research combining glaciology, numerical modeling, and robotics engineering is an engaging way to show how robotics can assist scientists in collecting hazardous field measurements. Our outreach activities will leverage Dartmouth's current NSF GK-12 program, build on faculty-educator relationships established during University of Maine's recent GK-12 program, and incorporate project results into University of Maine's IDEAS initiative, which integrates computational modeling with the existing science curriculum at the middle school level. This award has field work in Antarctica.
This award supports a detailed, molecular level characterization of dissolved organic carbon and microbes in Antarctic ice cores. Using the most modern biological (genomic), geochemical techniques, and advanced chemical instrumentation researchers will 1) optimize protocols for collecting, extracting and amplifying DNA from deep ice cores suitable for use in next generation pyrosequencing; 2) determine the microbial diversity within the ice core; and 3) obtain and analyze detailed molecular characterizations of the carbon in the ice by ultrahigh resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS). With this pilot study investigators will be able to quantify the amount of material (microbial biomass and carbon) required to perform these characterizations, which is needed to inform future ice coring projects. The ultimate goal will be to develop protocols that maximize the yield, while minimizing the amount of ice required. The broader impacts include education and outreach at both the local and national levels. As a faculty mentor with the American Indian Research Opportunities and BRIDGES programs at Montana State University, Foreman will serve as a mentor to a Native American student in the lab during the summer months. Susan Kelly is an Education and Outreach Coordinator with a MS degree in Geology and over 10 years of experience in science outreach. She will coordinate efforts for comprehensive educational collaboration with the Hardin School District on the Crow Indian Reservation in South-central Montana.
1043421/Severinghaus<br/><br/>This award supports a project to obtain samples of ice in selected intervals for replication and verification of the validity and spatial representativeness of key results in the WAIS Divide ice core, and to obtain additional ice samples in areas of intense scientific interest where demand is high. The US Ice Core Working Group recommended in 2003 that NSF pursue the means to take replicate samples, termed "replicate coring". This recommendation was part of an agreement to reduce the diameter of the (then) new drilling system (the DISC drill) core to 12.2 cm to lighten logistics burdens, and the science community accepted the reduction in ice sample with the understanding that replicate coring would be able to provide extra sample volume in key intervals. The WAIS Divide effort would particularly benefit from replicate coring, because of the unique quality of the expected gas record and the large samples needed for gases and gas isotopes; thus this proposal to employ replicate coring at WAIS Divide. In addition, scientific demand for ice samples has been, and will continue to be, very unevenly distributed, with the ice core archive being completely depleted in depth intervals of high scientific interest (abrupt climate changes, volcanic sulfate horizons, meteor impact horizons, for example). The broader impacts of the proposed research may include identification of leads and lags between Greenland, tropical, and Antarctic climate change, enabling critical tests of hypotheses for the mechanism of abrupt climate change. Improved understanding of volcanic impacts on atmospheric chemistry and climate may also emerge. This understanding may ultimately help improve climate models and prediction of the Earth System feedback response to ongoing human perturbation in coming centuries. Outreach and public education about climate change are integral components of the PIs' activities and the proposed work will enhance these efforts. Broader impacts also include education and training of 2 postdoctoral scholars and 1 graduate student, and invaluable field experience for the graduate and undergraduate students who will likely make up the core processing team at WAIS Divide.
This award supports a project to examine and test a 3-step process model for explosive ice-shelf disintegration that emerged in the wake of the recent 2008 and 2009 events of the Wilkins Ice Shelf. The model is conditioned on Summer melt-driven increase in free-surface water coupled with surface and basal crevasse density growth necessary to satisfy an "enabling condition". Once met, the collapse proceeds through three steps: (Step 1), calving of a "leading phalanx" of tabular icebergs from the seaward ice front of the ice shelf which creates in its wake a region, called a "mosh pit" (located between the phalanx and the edge of the intact ice shelf), where ocean surface-gravity waves are trapped by reflection (a fast mechanically enabled process), (Step 2), and a rapid, runaway conversion of gravitational potential energy into ocean-wave energy by iceberg capsize and fragmentation within the "mosh pit" which leads to further wave-induced calving, capsize and fragmentation (Step 3). The project will be conducted by a multidisciplinary team and will focus on theoretical model development, numerical method development and application and new observations. The project will participate in both the Research Experience for Undergraduates program in the Physics Department and the Summer Research Early Identification Program (SR-EIP) that fosters participation in research by underrepresented minorities. The PIs, postdoctoral scholar, graduate students and unfunded participants will develop a graduate-level seminar/tutorial to introduce advanced computational methods to glaciology. A postdoctoral scholar and graduate student will be trained in new research techniques during the project.
The proposed work will investigate changes in the compositional variation of glacial tills over time across two concentric sequences of Pleistocene moraines located adjacent to the heads of East Antarctic outlet glaciers in the Transantarctic Mountains (TAM). The chronologic framework for this work will be generated from cosmogenic exposure ages of boulders on prominent morainal ridges. The PIs hypothesize that variations in till composition may indicate a change in ice flow direction or a change in the composition of the original source area, while ages of the moraines provide a long-term terrestrial perspective on ice sheet dynamics. Both results are vital for modeling experiments that aim to reconstruct the East Antarctic Ice Sheet and assess its role in the global climate system and its potential impact on global sea level rise. The variation of till compositions through time also allows for a more accurate interpretation of sediment cores from the Ross Sea and the Southern Ocean. Additionally, till exposures at the head of some East Antarctic outlet glaciers have been shown to contain subglacial material derived from East Antarctic bedrock, providing a window through the ice to view East Antarctica?s inaccessible bedrock. Till samples will be collected from two well-preserved sequences of moraine crests at Mt. Howe (head of Scott Glacier) and Mt. Achernar (between Beardmore and Nimrod Glaciers). Each size fraction in glacial till provides potentially valuable information, and the PIs will measure the petrography of the clast and sand fractions, quantitative X-ray diffraction on the crushed <2mm fraction, elemental abundance of the silt/clay fraction, and U/Pb of detrital zircons in the sand fraction. Data collection will rely on established methods previously used in this region and the PIs will also explore new methods to assess their efficacy. On the same moraines crests sampled for provenance studies, the PIs will sample for cosmogenic surface exposure analyses to provide a chronologic framework at the sites for provenance changes through time. <br/><br/>Broader Impact <br/>The proposed research involves graduate and undergraduate training in a diverse array of laboratory methods. Students and PIs will be make presentations to community and campus groups, as well as conduct interviews with local news outlets. The proposed work also establishes a new, potentially long-term, collaboration between scientists at IUPUI and LDEO and brings a new PI (Kaplan) into the field of Antarctic Earth Sciences.
MacAyeal/0944248<br/><br/>This award supports a project to develop a better understanding of the processes and conditions that trigger ice shelf instability and explosive disintegration. A significant product of the proposed research will be the establishment of parameterizations of micro- and meso-scale ice-shelf surface processes needed in large scale ice-sheet models designed to predict future sea level rise. The proposed research represents a 3-year effort to conduct numerical model studies of 6 aspects of surface-water evolution on Antarctic ice shelves. These 6 model-study areas include energy balance models of melting ice-shelf surfaces, with treatment of surface ponds and water-filled crevasses, distributed, Darcian water flow modeling to simulate initial firn melting, brine infiltration, pond drainage and crevasse filling, ice-shelf surface topography evolution modeling by phase change (surface melting and freezing), surface-runoff driven erosion and seepage flows, mass loading and flexure effects of ice-shelf and iceberg surfaces; feedbacks between surface-water loads and flexure stresses; possible seiche phenomena of the surface water, ice and underlying ocean that constitute a mechanism for, inducing surface crevassing., surface pond and crevasse convection, and basal crevasse thermohaline convection (as a phenomena related to area 5 above). The broader impacts of the proposed work bears on the socio-environmental concerns of climate change and sea-level rise, and will contribute to the important goal of advising public policy. The project will form the basis of a dissertation project of a graduate student whose training will contribute to the scientific workforce of the nation and the PI and graduate student will additionally participate in a summer science-enrichment program for high-school teachers organized by colleagues at the University of Chicago.
Aciego/1043367<br/><br/>This award supports the development of a new method for determining the absolute age of samples from deep ice cores. The project will: (1) prove the efficacy of the Uranium-series dating method on a high accumulation rate ice core, and (2) address the uncertainties in the age dating of the EPICA Dronning-Maud Land (EDML) ice core in the lower 300 m. The well-dated upper section of the ice core (down to 150,000 years at 2415.7 m) will provide excellent constraints to validate the ages determined by the U-series method. After verification, and possible adjustments to the laboratory chemistry, the method will be applied to a suite of ice samples of unknown age in the lower part of the EDML ice core. Within the lower 300 m of this ice core, the climate records are disturbed by tilting and folding of the ice, and, due to the uncertainties in how the ice has flowed, it is impossible to determine if accurate age dates can be obtained to access the record of climate change, or if mixing of the ice is too incoherent. As part of the methodology, the PI will measure surface area of dust included in the ice using a gas adsorption technique developed for ultra-small samples; these measurements will be made on a BET nano-scale which is to be purchased from the funding of this project. Intellectual Merit: The proposed research will contribute to our understanding of geophysical processes that fold and tilt ice. This will allow new paleoclimate records to be recovered from ice cores that have been physically deformed and disturbed and previously did not permit accurate dating. Broader Impacts: This funding will provide support for one PhD graduate student and contribute to their training as a researcher in geochemistry and paleoclimate studies. The PI will teach classes in earth surface processes (including glaciology) and in advanced isotope geochemistry. Work related to this research will be integrated as a teaching tool into the classroom to provide a hands-on, relevant learning experience. Furthermore, samples examined as part of this research will be made available from the AWI archive in Bremerhaven, Germany as part of the collaboration between the PI in the United States and the European ice core community.
Notothenioid fishes that dominate the fish fauna surrounding Antarctica have been evolving for 10-14 million years at a nearly constant body temperature of ~0C throughout their life histories. As a result, this group of animals is uniquely suited to studies aimed at understanding and identifying features of physiology and biochemistry that result from the process of evolution at cold body temperature. This project has three major objectives aimed at examining adaptations for life in cold environments: <br/><br/>1. Identify the amino acid substitutions in the fatty acid-binding pocket of fatty acyl CoA synthetase (FACS) that explain its substrate specificity. Fatty acids are a major fuel of energy metabolism in Antarctic fishes. FACS catalyzes the condensation of CoASH and fatty acids to fatty acyl CoA esters, a step required for subsequent metabolism of these important compounds. This research may permit us to resolve the specific amino acid substitutions that explain both substrate specificity and preservation of catalytic rate of notothenioid FACS at cold physiological temperatures.<br/><br/>2. Produce a rigorous biochemical and biophysical characterization of the intracellular calcium-binding protein, parvalbumin, from white axial musculature of Antarctic fishes. Parvalbumin plays a pivotal role in facilitating the relaxation phase of fast-contracting muscles and is a likely site of strong selective pressure. Preliminary data strongly indicate that the protein from Antarctic fishes has been modified to ensure function at cold temperature. A suite of physical techniques will be used to determine dissociation constants of Antarctic fish parvalbumins for calcium and magnesium and unidirectional rate constants of ion-dissociation from the protein. Full-length cDNA clones for Antarctic fish parvalbumin(s) will permit deduction of primary amino acid sequence These data will yield insight into structural elements that permit the protein from notothenioid fishes to function at very cold body temperature.<br/><br/>3. Conduct a broad survey of the pattern of cardiac myoglobin expression in the Suborder Notothenoidei. Previous work has indicated a variable pattern of presence or absence of the intracellular oxygen-binding protein, myoglobin (Mb), in hearts of one family of Antarctic notothenioid fishes (Channichthyidae; icefishes). Because Mb is of physiological value in species that express the protein, the observed pattern of interspecific expression has been attributed to unusually low niche competition in the Southern Ocean. This leads to the prediction that similar loss of cardiac Mb should be observed in other notothenioid taxa. This part of the project will survey for the presence and absence of cardiac Mb in as many notothenioid species as possible and, if Mb-lacking species are detected, will extend analyses to determine the mechanism(s) responsible for loss of its expression using molecular biological techniques.
ACT K. Mopper & D. Kieber OPP 9527255 & 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.
This project studies fossils from two to three hundred million year old rocks in the Allan Hills area of Antarctica. Similar deposits from lower latitudes have been used to develop a model of Permo-Triassic climate, wherein melting of continental glaciers in the early Permian leads to the establishment of forests in a cold, wet climate. Conditions became warmer and dryer by the early Triassic, inhibiting plant growth until a moistening climate in the late Triassic allowed plant to flourish once again. This project will test and refine this model and investigate the general effects of climate change on landscapes and ecosystems using the unique exposures and well-preserved fossil and sediment records in the Allan Hills area. The area will be searched for fossil forests, vertebrate tracks and burrows, arthropod trackways, and subaqueously produced biogenic structures, which have been found in other areas of Antarctica. Finds will be integrated with previous paleobiologic studies to reconstruct and interpret ecosystems and their changes. Structures and rock types documenting the end phases of continental glaciation and other major episodic sedimentations will also be described and interpreted. This project contributes to understanding the: (1) evolution of terrestrial and freshwater ecosystems and how they were affected by the end-Permian extinction, (2) abundance and diversity of terrestrial and aquatic arthropods at high latitudes, (3) paleogeographic distribution and evolution of vertebrates and invertebrates as recorded by trace and body fossils; and (3) response of landscapes to changes in climate.<br/><br/>In terms of broader impacts, this project will provide an outstanding introduction to field research for graduate and undergraduate students, and generate related opportunities for several undergraduates. It will also stimulate exchange of ideas among research and primarily undergraduate institutions. Novel outreach activities are also planned to convey Earth history to the general public, including a short film on the research process and products, and paintings by a professional scientific illustrator of Permo-Traissic landscapes and ecosystems.
0124049<br/>Berger<br/><br/>This award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the Dry Valleys of the McMurdo Sound region of Antarctica. Using a modified Livingstone corer, transects of long cores will be obtained from Lakes Fryxell, Bonney, Joyce, and Vanda. A multiparameter approach will be employed which is designed to extract the greatest possible amount of former water-level, glaciological, and paleoenvironmental data from Dry Valleys lakes. Estimates of hydrologic changes will come from different proxies, including grain size, stratigraphy, evaporite mineralogy, stable isotope and trace element chemistry, and diatom assemblage analysis. The chronology, necessary to integrate the cores with the geomorphological record, as well as for comparisons with Antarctic ice-core and glacial records, will come from Uranium-Thorium, Uranium-Helium, and Carbon-14 dating of carbonates, as well as luminescence sediment dating. Evaluation of the link between lake-level and climate will come from hydrological and energy-balance modelling. Combination of the more continuous lake-core sequences with the spatially extensive geomorphological record will result in an integrated Antarctic lake-level and paleoclimate dataset that extends back at least 30,000 years. This record will be compared to Dry Valleys glacier records and to the Antarctic ice cores to address questions of regional climate variability, and then to other Southern Hemisphere and Northern Hemisphere records to assess interhemispheric synchrony or asynchrony of climate change.
High latitude deep ice cores contain fundamental records of polar temperatures, atmospheric dust loads (and continental aridity), greenhouse gas concentrations, the status of the biosphere, and other essential properties of past environments. An accurate chronology for these records is needed if their significance is to be fully realized. The dating challenge has stimulated efforts at orbital tuning. In this approach, one varies a timescale, within allowable limits, to optimize the match between a paleoenvironmental property and a curve of insolation through time. The ideal property would vary with time due to direct insolation forcing. It would be unaffected by complex climate feedbacks and teleconnections, and it would give a clean record with high signal/noise ratio. It is argued strongly that the O2/N2 ratio of ice core trapped gases is such a property, and evidence is presented that this property, whose atmospheric ratio is nearly constant, is tied to local summertime insolation. This award will support a project to analyze the O2/N2 ratios at 1 kyr intervals from ~ 115-400 ka in the Vostok ice core. Ancillary measurements will be made of Ar/N2, and Ne/N2 and heavy noble gas ratios, in order to understand bubble close-off fractionation and its manifestation in the Vostok trapped gas record. O2/N2 variations will be matched with summertime insolation at Vostok to achieve a high-accuracy chronology for the Vostok core. The Vostok and other correlatable climate records will then be reexamined to improve our understanding of the dynamics of Pleistocene climate change.
This award is for support for a program to investigate the visual stratigraphy, index physical properties, relaxation characteristics and crystalline structure of ice cores from Siple Dome, West Antarctica. This investigation will include measurements of a time-priority nature that must be initiated at the drill site on freshly-drilled cores. This will be especially true of cores from the brittle ice zone, which is expected to comprise a significant fraction of the ice core. The brittle zone includes ice in which relaxation , resulting from the release of confining pressure is maximized and leads to significant changes in the mechanical condition of the core that must be considered in relation to the processing and analysis of ice samples for entrapped gas and chemical studies. This relaxation will be monitored via precision density measurements made initially at the drill site and repeated at intervals back in the U.S. Other studies will include measurement of the annual layering in the core to as great a depth as visual stratigraphy can be deciphered, crystal size measurements as a function of depth and age, c-axis fabric studies, and analysis of the physical properties of any debris-bearing basal ice and its relationship to the underlying bedrock. Only through careful documentation and analysis of these key properties can we hope to accurately assess the dynamic state of the ice and the age-depth relationships essential to deciphering the paleoclimate record at this location.