USAP-DC

{"dp_type": "Project", "free_text": "data analysis"}

[{"awards": null, "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 12 Feb 2024 00:00:00 GMT", "description": "Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function.\u003cbr/\u003e \u003cbr/\u003e \u003cbr/\u003eTo understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "Palmer Station; BENTHIC; PENGUINS; FLUORESCENCE; PHYTOPLANKTON", "locations": "Palmer Station", "north": null, "nsf_funding_programs": null, "paleo_time": null, "persons": null, "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots", "uid": "p0010448", "west": null}, {"awards": "2317927 Hills, Benjamin", "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": "Mon, 07 Aug 2023 00:00:00 GMT", "description": "Ice flow is resisted by frictional forces that keep a glacier from immediately sliding into the ocean. Friction comes in two varieties: internal friction within the ice column which resists ice deformation and basal friction which resists ice sliding over its bedrock substrate. Partitioning between internal and basal friction is difficult since both have similar expressions at the most common target for data collection?the ice-sheet surface. However, understanding this partitioning is important because the physical processes that control internal and basal friction act and evolve at different timescales. This project combines spaceborne remote sensing observations from the ice-sheet surface with ice-penetrating radar data that images the internal structure of the ice sheet in order to partition the contribution of each source of friction. Results will advance the fundamental understanding of ice flow and will strengthen projections of future sea-level rise. Broader Impacts of the project include facilitating data reuse for the ice-sheet research community; the strategy for distributing the software toolkit includes student mentorship and hackathon teaching.\r\n\r\nThe researcher will expand the impact of existing ice-penetrating datasets by 1) developing new open-source algorithms for extraction of englacial stratigraphy; 2) creating stratigraphy data products that can be assimilated into future studies of ice motion; and 3) using statistical analyses to integrate radar datasets into larger-scale interpretations with remote sensing datasets of ice-surface velocity, altimetry, climate variables, and model-derived basal friction. The computational tools developed as part of this effort will be integrated and released as a reusable software toolkit for ice-penetrating radar data analysis. The toolkit will be validated and tested by deployment to cloud-hosted JupyterHub instances, which will serve as a singular interface to access radar and remote sensing data, load them into a unified framework, step through a predefined processing flow, and carry out statistical analyses. In some areas, the imaged englacial stratigraphy will deviate from the ice-dynamic setting expected based on surface measurements alone. There, the internal dynamics (or ice-dynamic history) are inconsistent with the surface dynamics, likely because internal friction is poorly constrained and misattributed to basal friction instead. This work will develop the data and statistical tools for constraining internal friction from ice-penetrating radar, making those data products and tools available for future work.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING", "is_usap_dc": true, "keywords": "GLACIER MOTION/ICE SHEET MOTION; BT-67; Antarctica; GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHY; DHC-6; ICE SHEETS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Post Doc/Travel", "paleo_time": null, "persons": "Hills, Benjamin", "platforms": "AIR-BASED PLATFORMS \u003e PROPELLER \u003e BT-67; AIR-BASED PLATFORMS \u003e PROPELLER \u003e DHC-6", "repositories": null, "science_programs": null, "south": -90.0, "title": "Postdoctoral Fellowship: OPP-PRF: Disentangling Ice-sheet Internal and Basal Processes through Novel Ice-penetrating Radar Integration Built on Scalable, Cloud-based Infrastructure", "uid": "p0010428", "west": -180.0}, {"awards": "2220968 Stewart, Andrew; 2220969 Manucharyan, Georgy", "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": "The world ocean is continuously in motion, and a large fraction of this motion takes the form of \"eddies\", nearly-horizontal swirls of water spanning tens to hundreds of kilometers. These eddies affect the ocean by mediating large-scale currents, redistributing heat, and supplying nutrients to oceanic ecosystems. Consequently, the ocean science community has historically invested substantial effort in characterizing the properties and impact of these eddies. In polar regions, the sea ice cover inhibits observations of eddies, and the relatively small horizontal size of the eddies hampers computer simulations of their behavior. Nonetheless, previous studies have identified an active population of eddies beneath the Arctic sea ice and shown that these eddies play a crucial role in maintaining the large-scale circulation in the Arctic seas. However, there has been no systematic attempt to study such eddies under Antarctic sea ice, leaving a significant gap in our understanding of eddies and their contribution to the large-scale ocean circulation around Antarctica.\r\n\r\nThe proposed research combines multiple approaches to improve our understanding of the eddy dynamics. Statistical characterizations of the sub-sea ice eddy field will be derived using hydrographic observations under Antarctic sea ice from Argo floats and instrumented seals. High-resolution global ocean and sea ice models will be used to track the simulated eddies back to their formation sites to identify the eddy formation mechanisms. Theoretical calculations will be conducted to test the hypothesis that the eddies primarily originate from hydrodynamic instabilities associated with subsurface density gradients. These theoretical, modeling, and data analysis approaches will be combined to estimate the eddies\u0027 contribution to lateral tracer transports and their impact on mean circulations of the near-Antarctic ocean. The proposed work will facilitate future scientific endeavors by providing publicly-available databases of detected eddy properties. This project will support the research of several junior scientists: an undergraduate student, two graduate students, and an early-career faculty member.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; OCEAN CURRENTS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Stewart, Andrew; Bianchi, Daniele", "platforms": null, "repositories": null, "science_programs": null, "south": -90.0, "title": "Collaborative Research: Characteristics and Origins of Eddies beneath Antarctic Sea Ice", "uid": "p0010366", "west": -180.0}, {"awards": "1745009 Kohut, Josh; 1745011 Klinck, John; 1745081 Bernard, Kim; 1745018 Fraser, William; 1745023 Hennon, Tyler; 1744884 Oliver, Matthew", "bounds_geometry": "POLYGON((-75 -60,-73 -60,-71 -60,-69 -60,-67 -60,-65 -60,-63 -60,-61 -60,-59 -60,-57 -60,-55 -60,-55 -61,-55 -62,-55 -63,-55 -64,-55 -65,-55 -66,-55 -67,-55 -68,-55 -69,-55 -70,-57 -70,-59 -70,-61 -70,-63 -70,-65 -70,-67 -70,-69 -70,-71 -70,-73 -70,-75 -70,-75 -69,-75 -68,-75 -67,-75 -66,-75 -65,-75 -64,-75 -63,-75 -62,-75 -61,-75 -60))", "dataset_titles": "Antarctic ACROBAT data; CTD Data from IFCB Sampling; Finite Time Lyapunov Exponent Results, Calculated from High Frequency Radar Observed Surface Currents; High Frequency Radar, Palmer Deep; IFCB Image Data; Relative Particle Density; SWARM AMLR moorings - acoustic data; SWARM Glider Data near Palmer Deep; WAP model float data; Winds from Joubin and Wauwerman Islands", "datasets": [{"dataset_uid": "200393", "doi": "10.26008/1912/bco-dmo.865002.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "IFCB Image Data", "url": "https://www.bco-dmo.org/dataset/865002"}, {"dataset_uid": "200396", "doi": "10.26008/1912/bco-dmo.867442.2", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "WAP model float data", "url": "https://www.bco-dmo.org/dataset/867442"}, {"dataset_uid": "200395", "doi": "10.26008/1912/bco-dmo.872729.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "SWARM AMLR moorings - acoustic data", "url": "https://www.bco-dmo.org/dataset/872729"}, {"dataset_uid": "200392", "doi": "10.26008/1912/bco-dmo.917884.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "High Frequency Radar, Palmer Deep", "url": "https://www.bco-dmo.org/dataset/917884"}, {"dataset_uid": "200398", "doi": "", "keywords": null, "people": null, "repository": "IOOS Glider DAAC", "science_program": null, "title": "SWARM Glider Data near Palmer Deep", "url": "https://gliders.ioos.us/erddap/search/index.html?page=1\u0026itemsPerPage=1000\u0026searchFor=swarm"}, {"dataset_uid": "200397", "doi": "10.26008/1912/bco-dmo.865098.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Winds from Joubin and Wauwerman Islands", "url": "https://www.bco-dmo.org/dataset/865098"}, {"dataset_uid": "200394", "doi": "10.26008/1912/bco-dmo.917926.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Relative Particle Density", "url": "https://www.bco-dmo.org/dataset/917926"}, {"dataset_uid": "200389", "doi": "", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Antarctic ACROBAT data", "url": "https://www.bco-dmo.org/dataset/916046"}, {"dataset_uid": "200390", "doi": "10.26008/1912/bco-dmo.865030.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "CTD Data from IFCB Sampling", "url": "https://www.bco-dmo.org/dataset/865030"}, {"dataset_uid": "200391", "doi": "10.26008/1912/bco-dmo.917914.1", "keywords": null, "people": null, "repository": "BCO-DMO", "science_program": null, "title": "Finite Time Lyapunov Exponent Results, Calculated from High Frequency Radar Observed Surface Currents", "url": "https://www.bco-dmo.org/dataset/917914"}], "date_created": "Tue, 05 Jul 2022 00:00:00 GMT", "description": "Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function.\u003cbr/\u003e \u003cbr/\u003e \u003cbr/\u003eTo understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.\u003cbr/\u003e\u003cbr/\u003eThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": -55.0, "geometry": "POINT(-65 -65)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CONDUCTIVITY SENSORS \u003e CONDUCTIVITY METERS; IN SITU/LABORATORY INSTRUMENTS \u003e RADIATION SENSORS", "is_usap_dc": true, "keywords": "MOORED; WATER TEMPERATURE; CONDUCTIVITY; FLUORESCENCE; UNCREWED VEHICLES; Palmer Station; PHOTOSYNTHETICALLY ACTIVE RADIATION; PELAGIC; OCEAN MIXED LAYER; SURFACE; SALINITY; WATER PRESSURE; LIVING ORGANISM; MODELS; ACOUSTIC SCATTERING", "locations": "Palmer Station", "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Integrated System Science; Antarctic Ocean and Atmospheric Sciences; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Instrumentation and Support", "paleo_time": "NOT APPLICABLE", "persons": "Bernard, Kim; Oliver, Matthew; Kohut, Josh; Fraser, William; Klinck, John M.; Statcewich, Hank", "platforms": "LIVING ORGANISM-BASED PLATFORMS \u003e LIVING ORGANISM; OTHER \u003e MODELS; WATER-BASED PLATFORMS \u003e BUOYS \u003e MOORED; WATER-BASED PLATFORMS \u003e UNCREWED VEHICLES; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE", "repo": "BCO-DMO", "repositories": "BCO-DMO; IOOS Glider DAAC", "science_programs": null, "south": -70.0, "title": "Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots", "uid": "p0010346", "west": -75.0}, {"awards": "2023303 Purkey, Sarah; 2023244 Stewart, Andrew; 2023259 Thompson, Andrew", "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": "Ocean CFC reconstructed data product", "datasets": [{"dataset_uid": "601752", "doi": "10.15784/601752", "keywords": "Antarctica; CFCs; GLODAP; Ocean Model; Ocean Ventilation; Southern Ocean", "people": "Purkey, Sarah; Cimoli, Laura; Gebbie, Jack", "repository": "USAP-DC", "science_program": null, "title": "Ocean CFC reconstructed data product", "url": "https://www.usap-dc.org/view/dataset/601752"}], "date_created": "Thu, 01 Jul 2021 00:00:00 GMT", "description": "The formation of dense Antarctic Bottom Water (AABW) and its export northward from the Antarctic continent is one of the key components of the global ocean overturning circulation, and plays a critical role in regulating Earth\u0027s climate on multi-decadal-to-millennial time scales. Recent studies of the global ocean overturning circulation have increasingly emphasized its three-dimensional structure: AABW is produced in a handful of distinct sites around the Antarctic continent, and there is a pronounced asymmetry in the allocation of AABW transports into the Atlantic, Indian and Pacific basins. The connectivity of AABW between the Antarctic continental shelf and the northern basins is mediated by the Antarctic Circumpolar Current (ACC), a circumpolar eastward flow that also serves as the primary route for inter-basin exchange.\r\n\r\nThe mapping from different shelf AABW sources to the northern basins dictates the response of the global MOC to localized variability or shifts in the state of the Antarctic shelf, for example due to major glacier calving events or modified inputs of freshwater from the Antarctic ice sheet. At present this mapping is not well constrained, with conflicting conclusions drawn in previous studies: at one extreme the ACC has been suggested to be a ``conduit\u0027\u0027 that simply allows each variety of AABW to transit directly northward; at the other extreme, it has been suggested that the ACC ``blends\u0027\u0027 all shelf AABW sources together before they reach the northern basins. Such conflicts arise, in part, because little is understood about the physics that determines AABW\u0027s pathways across the ACC.\r\n\r\nTo close this gap in understanding, this collaborative project draws on three complementary analytical tools: process-oriented modeling of AABW export across the ACC, a high-resolution global ocean model, and an observationally-constrained estimate of the global circulation. The PIs will first identify and quantify the pathways of AABW across the ACC by using these tools to propagate passive tracers that identify each of the four major AABW formation sites. They will then use a suite of process model sensitivity experiments to develop a theory for what controls meridional versus inter-basin transport of AABW in the ACC, and transfer this theory to interpret the AABW pathways simulated in the global model. Finally, they will combine the process model, global model and the observationally-constrained circulation product to map the rates at which AABW is transformed into lighter waters, and relate these transformation rates to the diagnosed pathways of AABW across the ACC. This combination of approaches allow the PIs to not only constrain the three-dimensional circulation of AABW from Antarctica to the northern basins, but also provides a mechanistic understanding of the circulation that can be transferred to past or future climates.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "AMD; MODELS; USAP-DC; WATER MASSES; Southern Ocean; Amd/Us; OCEAN CURRENTS; COMPUTERS; Antarctic Circumpolar Current; USA/NSF", "locations": "Southern Ocean", "north": -60.0, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences; Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Stewart, Andrew; Thompson, Andrew; Purkey, Sarah", "platforms": "OTHER \u003e MODELS \u003e COMPUTERS; OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: The Antarctic Circumpolar Current: A Conduit or Blender of Antarctic Bottom Waters?", "uid": "p0010220", "west": -180.0}, {"awards": "1937748 Sumner, Dawn", "bounds_geometry": "POINT(163.183333 -77.616667)", "dataset_titles": null, "datasets": null, "date_created": "Wed, 30 Jun 2021 00:00:00 GMT", "description": "This project focuses on understanding annual changes in microbial life that grows on the bottom of Lake Fryxell, Antarctica. Because of its polar latitude, photosynthesis can only occur during the summer. During summer, photosynthetic bacteria supply communities with energy and oxygen. However, it is unknown how the microbes behave in the dark winter, when observations are not possible. This project will perform laboratory experiments with a cyanobacterial mat grown from Lake Fryxell samples. Once fieldwork is allowed, we will install environmental monitors and light-blocking shades over small parts of the communities in Lake Fryxell. The shades will extend winter conditions into the spring to allow researchers to characterize the winter behavior of the microbial communities. Researchers will measure changes in the water chemistry due to their activities when they first receive light as the shades are removed. Results are expected to provide insights into how organisms interact with and change their environments. \r\n\r\nThe project extends these scientific results to building a better-prepared, more diverse workforce to perform scientific fieldwork. Fieldwork, including diving, will be performed in part by graduate students under the mentorship of world experts in Antarctic field science. In addition, the project will help students and early career scientists learn field skills by building an online \u201cGuide to Thrive.\u201d This web site will compile field tips ranging from basic gear use to advanced environmental protection techniques. Group leaders ranging from undergraduate teaching assistants to Antarctic expedition leaders will be able to choose appropriate components to build tailored guides for their participants to help them thrive in difficult field conditions. \r\n\r\nThe researchers will measure laboratory-based and field-based seasonal metabolic and biogeochemical changes in benthic mats using differential gene expression and geochemical gradients. They will identify seasonal phenotypic differences and ecosystem effects induced by spring oxygen production. To do so, researchers will install environmental sensors and opaque shades over mats at three depths in the lake. The following spring, they will sample shaded and unshaded mats, remove the shades, track changes in pore water O2, H2S, pH, and redox with microelectrodes, and sample mats for transcriptomic analyses at intervals guided by geochemical changes. Pore water will be sampled for nutrient analyses. Field research will be supplemented with: laboratory experiments to refine field techniques (expanded effort due to COVID field restrictions); gene expression data analysis; and integration of results into a seasonal model of productivity and nitrogen cycling in Lake Fryxell. Results will provide insights into several key priorities for NSF, including how biotic, abiotic and environmental components of the benthic mats interact to affect the regional ecosystem.\r\n", "east": 163.183333, "geometry": "POINT(163.183333 -77.616667)", "instruments": null, "is_usap_dc": true, "keywords": "Antarctica; Amd/Us; AMD; USA/NSF; FIELD SURVEYS; ECOSYSTEM FUNCTIONS; Lake Fryxell; USAP-DC; LAKE/POND", "locations": "Antarctica; Lake Fryxell", "north": -77.616667, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Integrated System Science", "paleo_time": null, "persons": "Sumner, Dawn; Mackey, Tyler", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repositories": null, "science_programs": null, "south": -77.616667, "title": "Seasonal Primary Productivity and Nitrogen Cycling in Photosynthetic Mats, Lake Fryxell, McMurdo Dry Valleys", "uid": "p0010219", "west": 163.183333}, {"awards": "1235094 Thurnherr, Andreas", "bounds_geometry": "POLYGON((-19 -19,-18.2 -19,-17.4 -19,-16.6 -19,-15.8 -19,-15 -19,-14.2 -19,-13.4 -19,-12.6 -19,-11.8 -19,-11 -19,-11 -19.4,-11 -19.8,-11 -20.2,-11 -20.6,-11 -21,-11 -21.4,-11 -21.8,-11 -22.2,-11 -22.6,-11 -23,-11.8 -23,-12.6 -23,-13.4 -23,-14.2 -23,-15 -23,-15.8 -23,-16.6 -23,-17.4 -23,-18.2 -23,-19 -23,-19 -22.6,-19 -22.2,-19 -21.8,-19 -21.4,-19 -21,-19 -20.6,-19 -20.2,-19 -19.8,-19 -19.4,-19 -19))", "dataset_titles": "Expedition Data; NBP1406 Expedition data; NBP1508 Expedition data; Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508; Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015); Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "datasets": [{"dataset_uid": "601354", "doi": "10.15784/601354", "keywords": "Current Measurements; LADCP; Mid-Ocean Ridge; NBP1508; Oceans; Physical Oceanography; R/v Nathaniel B. Palmer; South Atlantic Ocean", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601354"}, {"dataset_uid": "200153", "doi": "10.7284/903009", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1406 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "001408", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP1406"}, {"dataset_uid": "601353", "doi": null, "keywords": "CTD; CTD Data; Current Measurements; Current Meter; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508 (2015)", "url": "https://www.usap-dc.org/view/dataset/601353"}, {"dataset_uid": "601352", "doi": null, "keywords": "CTD; Mid-Ocean Ridge; Mooring; NBP1508; Oceans; Physical Oceanography; Pressure; R/v Nathaniel B. Palmer; Salinity; South Atlantic Ocean; Temperature", "people": "Thurnherr, Andreas", "repository": "USAP-DC", "science_program": null, "title": "Processed Current Measurement, Pressure, Salinity and Temperature Data from the Southern Mid-Atlantic Ridge Spreading acquired during R/V Nathaniel B. Palmer expedition NBP1508", "url": "https://www.usap-dc.org/view/dataset/601352"}, {"dataset_uid": "200154", "doi": "10.7284/906708", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1508 Expedition data", "url": "https://www.rvdata.us/search/cruise/NBP1508"}], "date_created": "Thu, 02 Jul 2020 00:00:00 GMT", "description": "Overview: In order to close the global overturning circulation, high-density deep- and bottom waters produced at high latitudes must be made less dense and upwell to shallower depths. Available observations from the subtropical South Atlantic indicate that the bulk of the mixing in the deep ocean there takes place over the topographically rough Mid-Atlantic Ridge, in particular in the quasi-regularly spaced \"fracture zone canyons\" corrugating the ridge flanks. There, dense water is advected toward the ridge crest (i.e. upwelled) by persistent along-valley currents that flow down the unidirectional density gradients, which are maintained by strong turbulence (diapycnal mixing). Most of the data on which these inferences are based were collected during the Brazil Basin Tracer Release Experiment (BBTRE) along a single ridge-flank canyon in the western South Atlantic near 22S where previous analyses have shown that both tidal mixing and overflow processes are important. Therefore, it is likely that both processes must be considered in order to understand and parameterize the effects of turbulence and mixing in the canyons corrugating the flanks of all slow-spreading ridges, which make up large fractions of the sea floor, in particular in the Atlantic, Indian and Southern Oceans. The primary aim of this follow-on project is to improve our understanding of the dynamics over the corrugated flanks of slow-spreading mid-ocean ridges. Due to the coarse sampling resolution and choice of station locations it is not possible to answer important questions, such as the relative importance of tidal and sill mixing, from the BBTRE data. Therefore, high-resolution surveys of hydrography, three-dimensional flow, turbulence and mixing will be carried out in two neighboring canyons and over the intervening topographic spur in the BBTRE region to determine the relative contributions of tidal and sill-related mixing. Furthermore, profiling moorings deployed on two nearby sill regions will be used to derive time series of spatially integrated mixing related buoyancy fluxes and to investigate the strong but unexplained sub-inertial variability of the along-canyon flow recorded previously. Additionally, three small moorings will be deployed in saddles between the two canyons to investigate inter-canyon exchange. The data analysis will include available data from previous experiments, including a set of tracer profiles that has not been analyzed before. Intellectual Merit: The corrugated flanks of slow-spreading ridges cover large areas of the sea floor of several major ocean basins. Therefore, understanding the dynamics in the ~100 km of ridge-flank canyons and its effects on the buoyancy and upwelling budget of the abyssal ocean is of global significance. In addition to determining the relative importance of tidal mixing and cross-sill flows in two canyons, the temporal variability of turbulence and mixing from tidal to yearly time scales will be investigated to gain insights into the forcing of the along-canyon flows, the exchange between neighboring canyons, and the eventual fate of the canyon waters. Broader Impacts: It is anticipated that insights gained during this project will improve our understanding of abyssal mixing in many different regions with similar bottom topography and provide the basis for better parameterizations of the effects of turbulence and mixing in large-scale circulation and climate models that cannot resolve these small-scale processes. As part of the project, a graduate student and a post-doctoral researcher will be trained in all aspects of observational physical oceanography, from data acquisition to interpretation. ", "east": -11.0, "geometry": "POINT(-15 -21)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CHEMICAL METERS/ANALYZERS \u003e FLUOROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MBES; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e THERMOSALINOGRAPHS", "is_usap_dc": true, "keywords": "OCEAN CURRENTS; South Atlantic Ocean; R/V NBP; WATER MASSES", "locations": "South Atlantic Ocean", "north": -19.0, "nsf_funding_programs": null, "paleo_time": null, "persons": "Thurnherr, Andreas", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "USAP-DC", "repositories": "R2R; USAP-DC", "science_programs": null, "south": -23.0, "title": "Collaborative Research: Flow, Turbulence and Mixing in Mid-Ocean Ridge Fracture Zone Canyons", "uid": "p0010114", "west": -19.0}, {"awards": "1443394 Pollard, David; 1443347 Condron, Alan", "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 Ice Sheet simulations for role of freshwater in future warming scenarios; Future climate response to Antarctic Ice Sheet melt caused by anthropogenic warming; Simulated changes in Southern Ocean salinity", "datasets": [{"dataset_uid": "601154", "doi": "10.15784/601154 ", "keywords": "Antarctic; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet; Ice Sheet Model; Meltwater; Model Data; Modeling; Model Output", "people": "Pollard, David", "repository": "USAP-DC", "science_program": null, "title": "Antarctic Ice Sheet simulations for role of freshwater in future warming scenarios", "url": "https://www.usap-dc.org/view/dataset/601154"}, {"dataset_uid": "601442", "doi": "10.15784/601442", "keywords": "Antarctica; Computer Model; Freshwater; Glaciers/ice Sheet; Glaciers/Ice Sheet; Model Data; Ocean Model; Oceans; Salinity", "people": "Condron, Alan", "repository": "USAP-DC", "science_program": null, "title": "Simulated changes in Southern Ocean salinity", "url": "https://www.usap-dc.org/view/dataset/601442"}, {"dataset_uid": "601449", "doi": "10.15784/601449", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Meltwater", "people": "Condron, Alan", "repository": "USAP-DC", "science_program": null, "title": "Future climate response to Antarctic Ice Sheet melt caused by anthropogenic warming", "url": "https://www.usap-dc.org/view/dataset/601449"}], "date_created": "Mon, 04 Feb 2019 00:00:00 GMT", "description": "A great deal of uncertainty remains over how changes in high-latitude freshwater forcing will impact the stability of global ocean circulation, and in particular the strength of the Atlantic Meridional Overturning Circulation (AMOC) in the next 100-300 years, especially in realistic models. Indeed, it is still not understood whether increased Southern Ocean freshwater forcing will act to intensify the AMOC and warm the Northern Hemisphere or weaken it and trigger a cooling. The requirement to accurately assess climate sensitivity to freshwater forcing is heightened by increasing evidence that the marine-based West Antarctic Ice Sheet (WAIS) is vulnerable to rapid retreat and collapse on multidecadal-to-centennial timescales. Observations collected over the last 30 years indicate that WAIS is losing ice at an accelerated rate and may signal that the ice sheet has already begun a rapid and irreversible collapse. In addition, future simulations of the Antarctic ice sheet by members of our Project Team show the potential for far more rapid Antarctic ice sheet retreat in the future than previously simulated, suggesting that the discharge of enormous fluxes of icebergs and freshwater to the Southern Ocean should be considered a possibility in the near-future. Here, we performed a suite of coupled numerical climate model simulations to more accurately determine the sensitivity of global ocean circulation to freshwater and iceberg discharge from the Antarctic Ice Sheet (AIS) in the future under IPCC RCP scenarios 4.5 and 8.5. In our model, the input of freshwater and ice was provided by a dynamic ice sheet-shelf model that predicts a full collapse of the WAIS in the next ~100 years. Significantly, we find that accounting for Antarctic discharge raises subsurface ocean temperatures by \u003e1\u00b0C at the ice sheet grounding line, relative to model simulations that are unable to capture this discharge. In contrast, we find that the increased meltwater causes a dramatic expansion of sea ice and a 2\u00b0 - 10\u00b0C cooling of the surface air and surface ocean temperatures over the Southern Ocean that would have the potential to stabilize/reduce projected future ice sheet melt rates. Our work thus highlights that the future stability of the Antarctic ice sheet will likely be governed by whether any surface cooling can counteract any increased rates of subsurface melt.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "USAP-DC; USA/NSF; AMD; MODELS; Amd/Us; Antarctica; GLACIERS/ICE SHEETS", "locations": "Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Pollard, David; Condron, Alan; DeConto, Robert", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Assessing the Global Climate Response to Melting of the Antarctic Ice Sheet", "uid": "p0010007", "west": -180.0}, {"awards": "1341311 Timmermann, Axel", "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": "784 ka transient Antarctic ice-sheet model simulation data", "datasets": [{"dataset_uid": "000247", "doi": "", "keywords": null, "people": null, "repository": "IBS Center for Climate Physics ICCP", "science_program": null, "title": "784 ka transient Antarctic ice-sheet model simulation data", "url": "http://climatedata.ibs.re.kr/grav/data/psu-love/antarctic-ice-sheet"}], "date_created": "Tue, 26 Jun 2018 00:00:00 GMT", "description": "This award supports a project to study the physical processes that synchronize glacial-scale variability between the Northern Hemisphere ice sheets and the Antarctic ice-sheet. Using a coupled numerical ice-sheet earth-system model, the research team will explore the cryospheric responses to past changes in greenhouse gas concentrations and variations in earth\u0027s orbit and tilt. First capturing the sensitivity of each individual ice-sheet to these forcings and then determining their joint variability induced by changes in sea level, ocean temperatures and atmospheric circulation, the researchers will quantify the relative roles of local versus remote effects on long-term ice volume variability. The numerical experiments will provide deeper physical insights into the underlying dynamics of past Antarctic ice-volume changes and their contribution to global sea level. Output from the transient earth system model simulations will be directly compared with ice-core data from previous and ongoing drilling efforts, such as West Antarctic Ice Sheet (WAIS) Divide. Specific questions that will be addressed include: 1) Did the high-latitude Southern Hemispheric atmospheric and oceanic climate, relevant to Antarctic ice sheet forcing, respond to local insolation variations, CO2, Northern Hemispheric changes, or a combination thereof?; 2) How did WAIS and East Antarctic Ice Sheet (EAIS) vary through the Last Glacial Termination and into the Holocene (21 ka- present)?; 3) Did the WAIS (or EAIS) contribute to rapid sea-level fluctuations during this period, such as Meltwater Pulse 1A? 4) Did WAIS collapse fully at Stage 5e (~ 125 ka), and what was its timing relative to the maximum Greenland retreat?; and 5) How did the synchronized behavior of Northern Hemisphere and Southern Hemisphere ice-sheet variations affect the strength of North Atlantic Deep Water and Antarctic Bottom Water formation and the respective overturning cells? The transient earth-system model simulations conducted as part of this project will be closely compared with paleo-climate reconstructions from ice cores, sediment cores and terrestrial data. This will generate an integrated understanding of the hemispheric contributions of deglacial climate change, the origin of meltwater pulses, and potential thresholds in the coupled ice-sheet climate system in response to different types of forcings. A well-informed long-term societal response to sea level rise requires a detailed understanding of ice-sheet sensitivities to external forcing. The proposed research will strongly contribute to this task through numerical modeling and paleo-data analysis. The research team will make the resulting model simulations available on the web-based data server at the Asia Pacific Data Research Center (APDRC) to enable further analysis by the scientific community. As part of this project a female graduate student and a postdoctoral researcher will receive training in earth-system and ice-sheet modeling and paleo-climate dynamics. This award has no field work in Antarctica.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Timmermann, Axel", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "IBS Center for Climate Physics ICCP", "repositories": "IBS Center for Climate Physics ICCP", "science_programs": null, "south": -90.0, "title": "Collaborative Research: Bipolar Coupling of late Quaternary Ice Sheet Variability", "uid": "p0000379", "west": -180.0}, {"awards": "1341362 Gast, Rebecca", "bounds_geometry": "POLYGON((-180 -65,-176 -65,-172 -65,-168 -65,-164 -65,-160 -65,-156 -65,-152 -65,-148 -65,-144 -65,-140 -65,-140 -66.5,-140 -68,-140 -69.5,-140 -71,-140 -72.5,-140 -74,-140 -75.5,-140 -77,-140 -78.5,-140 -80,-144 -80,-148 -80,-152 -80,-156 -80,-160 -80,-164 -80,-168 -80,-172 -80,-176 -80,180 -80,178 -80,176 -80,174 -80,172 -80,170 -80,168 -80,166 -80,164 -80,162 -80,160 -80,160 -78.5,160 -77,160 -75.5,160 -74,160 -72.5,160 -71,160 -69.5,160 -68,160 -66.5,160 -65,162 -65,164 -65,166 -65,168 -65,170 -65,172 -65,174 -65,176 -65,178 -65,-180 -65))", "dataset_titles": "Dinoflagellate sequende data", "datasets": [{"dataset_uid": "000240", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "Dinoflagellate sequende data", "url": "http://www.ncbi.nlm.nih.gov/bioproject/428208"}], "date_created": "Mon, 12 Feb 2018 00:00:00 GMT", "description": "Kleptoplasty, the temporary acquisition and use of functional chloroplasts derived from algal prey, is viewed as an important model for the early evolution of the permanent, endosymbiotically-derived chloroplasts found in all permanently photosynthetic eukaryotes. This project will study the evolutionary history and expression of plastid-targeted genes in an abundant Antarctic dinoflagellate that steals chloroplasts from an ecologically important alga, the haptophyte Phaeocystis. Algae play an important role in the fixation and export of CO2 in the Southern Ocean, and this project will explore the genetic basis for the function of these chimeric cells with regard to their functional adaptation to extreme environments and will study the evolutionary history and expression of plastid-targeted genes in both the host and recipient. The project seeks to determine whether the kleptoplastidic dinoflagellate utilizes ancestral plastid proteins to regulate its stolen plastid, and how their transcription is related to environmental factors that are relevant to the Southern Ocean environment (temperature and light). To accomplish these goals, the project will utilize high throughput transcriptome analysis and RNA-sequencing experiments with the dinoflagellate and Phaeocystis. \u003cbr/\u003e\u003cbr/\u003eThis work will help biologists understand the environmental success of this alternative nutritional strategy, and to assess the potential impact of anthropogenic climate change on the organism. The project will also contribute to the maintenance of a culture collection of heterotrophic, phototrophic and mixotrophic Antarctic protists that are available to the scientific community, and it will support the mentoring of a graduate student and a postdoctoral fellow. The work is being accomplished as an international collaboration between US and Canadian scientists, and in addition to publishing results in peer-reviewed journals, the investigators will incorporate aspects of this work into public outreach activities. These include field data analysis opportunities for middle school students and science-based art projects with local schools and museums.", "east": -140.0, "geometry": "POINT(-170 -72.5)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -65.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Gast, Rebecca", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "NCBI GenBank", "repositories": "NCBI GenBank", "science_programs": null, "south": -80.0, "title": "You are what you eat: The Role of Kleptoplasty in an Antarctic Dinoflagellate", "uid": "p0000302", "west": 160.0}, {"awards": "1245879 Nitsche, Frank O.", "bounds_geometry": null, "dataset_titles": "NBP1503 data collected during field expedition", "datasets": [{"dataset_uid": "200001", "doi": "10.7284/901478", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "NBP1503 data collected during field expedition", "url": "https://www.rvdata.us/search/cruise/NBP1503"}], "date_created": "Sun, 30 Jul 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThis project will determine the potential vulnerability of key ice streams to incursions of warmer ocean water onto the continental shelf and if this mechanism could already explain any of the observed thinning of the ice sheet. It will provide important constrains on ice dynamic of the investigated section of the EAIS, and thus will be critical for future ice sheet models and provide mechanisms for EAIS contributions to past sea level high-stand. The PI proposes to investigate four key ice stream systems on the continental shelf between ~90\u00c2\u00b0E and 160\u00c2\u00b0E. They will use multibeam bathymetry to identify if and where cross-shelf troughs exist to help determine whether these troughs could provide potential pathways for warmer ocean water. Furthermore, detailed analysis of morphological features of these troughs could provide information on past ice dynamic, maximum extent, and flow direction of related paleo ice streams. The PIs will also conduct water column measurements along these troughs and on the continental slope to determine whether warmer ocean water could enter the shelf in the near future, or if such water has already entered any troughs, and thus might be causing the observed thinning of some ice streams.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis project includes the participation and support of undergraduate and graduate students in field work and data analysis. The possible involvement of a PolarTREC teacher and the Earth2Class teachers program will reach out to K-12 students.", "east": 134.6, "geometry": "POINT(125.05 -64.5)", "instruments": null, "is_usap_dc": true, "keywords": "WATER TEMPERATURE; Polar; SALINITY; Antarctica; Southern Ocean; R/V NBP; BATHYMETRY", "locations": "Polar; Antarctica; Southern Ocean", "north": -63.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Nitsche, Frank O.", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -66.0, "title": "Vulnerability of East Antarctic Ice Streams to warm Ocean Water Incursions", "uid": "p0000394", "west": 115.5}, {"awards": "1148982 Hansen, Samantha", "bounds_geometry": "POLYGON((153.327 -73.032547,154.5063012 -73.032547,155.6856024 -73.032547,156.8649036 -73.032547,158.0442048 -73.032547,159.223506 -73.032547,160.4028072 -73.032547,161.5821084 -73.032547,162.7614096 -73.032547,163.9407108 -73.032547,165.120012 -73.032547,165.120012 -73.3530275,165.120012 -73.673508,165.120012 -73.9939885,165.120012 -74.314469,165.120012 -74.6349495,165.120012 -74.95543,165.120012 -75.2759105,165.120012 -75.596391,165.120012 -75.9168715,165.120012 -76.237352,163.9407108 -76.237352,162.7614096 -76.237352,161.5821084 -76.237352,160.4028072 -76.237352,159.223506 -76.237352,158.0442048 -76.237352,156.8649036 -76.237352,155.6856024 -76.237352,154.5063012 -76.237352,153.327 -76.237352,153.327 -75.9168715,153.327 -75.596391,153.327 -75.2759105,153.327 -74.95543,153.327 -74.6349495,153.327 -74.314469,153.327 -73.9939885,153.327 -73.673508,153.327 -73.3530275,153.327 -73.032547))", "dataset_titles": "Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins; Shear Wave Splitting Analysis and Seismic Anisotropy beneath the Northern Transantarctic Mountains; Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography; Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains", "datasets": [{"dataset_uid": "601194", "doi": "10.15784/601194", "keywords": "Antarctica; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Crustal Structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for Tectonic Origins", "url": "https://www.usap-dc.org/view/dataset/601194"}, {"dataset_uid": "601018", "doi": "10.15784/601018", "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Upper Mantle Shear Wave Velocity Structure beneath the Northern Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/601018"}, {"dataset_uid": "601019", "doi": "10.15784/601019", "keywords": "Antarctica; Geology/Geophysics - Other; GPS; Sample/collection Description; Sample/Collection Description; Seismology; Shearwave Spitting; Solid Earth; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Shear Wave Splitting Analysis and Seismic Anisotropy beneath the Northern Transantarctic Mountains", "url": "https://www.usap-dc.org/view/dataset/601019"}, {"dataset_uid": "601017", "doi": "10.15784/601017", "keywords": "Antarctica; Geology/Geophysics - Other; Model; Seismology; Solid Earth; Tomography; Transantarctic Mountains", "people": "Hansen, Samantha", "repository": "USAP-DC", "science_program": null, "title": "Upper Mantle Seismic Structure beneath the Northern Transantarctic Mountains from Regional P- and S-wave Tomography", "url": "https://www.usap-dc.org/view/dataset/601017"}], "date_created": "Sun, 04 Jun 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eTo understand Antarctica\u0027s geodynamic development, origin of the Transantarctic Mountains (TAMs) and the Wilkes Subglacial Basin (WSB) must be determined. Current constraints on the crustal thickness and seismic velocity structure beneath the TAMs and the WSB are limited, leading to uncertainties over competing geologic models that have been suggested to explain their formation. The PI proposes to broaden the investigation of this region with a new seismic deployment, the Transantarctic Mountains Northern Network (TAMNNET), a 15-station array across the northern TAMs and the WSB that will fill a major gap in seismic coverage. Data from TAMNNET will be combined with that from other previous and ongoing seismic initiatives and will be analyzed using proven modeling techniques to generate a detailed image of the seismic structure beneath the TAMs and the WSB. These data will be used to test three fundamental hypotheses: the TAMs are underlain by thickened crust, the WSB is characterized by thin crust and thick sedimentary layers, and slow seismic velocities are prevalent along strike beneath the TAMs. Results from the proposed study will provide new information about the nature and formation of the Antarctic continent and will help to advance our understanding of important global processes, such as mountain building and basin formation. The proposed research also has important implications for other fields of Antarctic science. Constraints on the origin of the TAMs uplift are critical for climate and ice sheet models, and new information acquired about variations in the thermal and lithospheric structure beneath the TAMs and the WSB will be used to estimate critical ice sheet boundary conditions. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThis project incorporates three educational strategies to promote the integration of teaching and research. Graduate students will be trained in Antarctic tectonics and seismic processing through hands-on fieldwork and data analysis techniques. Through NSF\u0027s PolarTREC program, the PI will work with K-12 educators. The PI will develop a three-week summer field program for recent high school graduates and early-career undergraduate students from Minority-Serving Institutions in Alabama. Teaching materials and participant experiences will be shared with individuals outside the program via a course website. Following the summer program, participants who were particularly engaged will be offered internship opportunities to analyze TAMNNET data. In successive years, the students could assist with fieldwork and could be recruited into the graduate program under the PI\u0027s supervision. Ultimately, this program would not only serve to educate undergraduates but would also generate a pipeline of underrepresented students into the geosciences.", "east": 165.120012, "geometry": "POINT(159.223506 -74.6349495)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "NOT APPLICABLE; USAP-DC", "locations": null, "north": -73.032547, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Hansen, Samantha", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -76.237352, "title": "CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin", "uid": "p0000300", "west": 153.327}, {"awards": "1043485 Curtice, Josh; 1043517 Clark, Peter; 1043018 Pollard, David", "bounds_geometry": "POLYGON((163.5 -77.57,163.685 -77.57,163.87 -77.57,164.055 -77.57,164.24 -77.57,164.425 -77.57,164.61 -77.57,164.795 -77.57,164.98 -77.57,165.165 -77.57,165.35 -77.57,165.35 -77.645,165.35 -77.72,165.35 -77.795,165.35 -77.87,165.35 -77.945,165.35 -78.02,165.35 -78.095,165.35 -78.17,165.35 -78.245,165.35 -78.32,165.165 -78.32,164.98 -78.32,164.795 -78.32,164.61 -78.32,164.425 -78.32,164.24 -78.32,164.055 -78.32,163.87 -78.32,163.685 -78.32,163.5 -78.32,163.5 -78.245,163.5 -78.17,163.5 -78.095,163.5 -78.02,163.5 -77.945,163.5 -77.87,163.5 -77.795,163.5 -77.72,163.5 -77.645,163.5 -77.57))", "dataset_titles": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea; Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "datasets": [{"dataset_uid": "600123", "doi": "10.15784/600123", "keywords": "Antarctica; Cosmogenic Dating; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean; WAIS", "people": "Curtice, Josh; Kurz, Mark D.", "repository": "USAP-DC", "science_program": null, "title": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "url": "https://www.usap-dc.org/view/dataset/600123"}, {"dataset_uid": "609639", "doi": "10.7265/N5NC5Z53", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Sheet Model", "people": "Pollard, David", "repository": "USAP-DC", "science_program": null, "title": "Ice Sheet Model Output, West Antarctic Ice Sheet Deglaciation", "url": "https://www.usap-dc.org/view/dataset/609639"}], "date_created": "Sat, 15 Oct 2016 00:00:00 GMT", "description": "1043517/Clark\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.", "east": 165.35, "geometry": "POINT(164.425 -77.945)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e DATA ANALYSIS \u003e ENVIRONMENTAL MODELING \u003e COMPUTER", "is_usap_dc": true, "keywords": "Ocean Depth; Not provided; Bed Elevation; Model Output; Sea Level Rise; Surface Accumulation Rate; Surface Melt Rate; Ocean Melt Rate; Total Ice Volume; Modeling; Calving Rate; Total Ice Area; LABORATORY", "locations": null, "north": -77.57, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Pollard, David; Curtice, Josh; Clark, Peter; Kurz, Mark D.", "platforms": "Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.32, "title": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "uid": "p0000194", "west": 163.5}, {"awards": "1142963 Warren, Stephen; 0739779 Warren, Stephen", "bounds_geometry": "POLYGON((157 -76,158.1 -76,159.2 -76,160.3 -76,161.4 -76,162.5 -76,163.6 -76,164.7 -76,165.8 -76,166.9 -76,168 -76,168 -76.2,168 -76.4,168 -76.6,168 -76.8,168 -77,168 -77.2,168 -77.4,168 -77.6,168 -77.8,168 -78,166.9 -78,165.8 -78,164.7 -78,163.6 -78,162.5 -78,161.4 -78,160.3 -78,159.2 -78,158.1 -78,157 -78,157 -77.8,157 -77.6,157 -77.4,157 -77.2,157 -77,157 -76.8,157 -76.6,157 -76.4,157 -76.2,157 -76))", "dataset_titles": "Ice on the Oceans of Snowball Earth Project Data", "datasets": [{"dataset_uid": "000183", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Ice on the Oceans of Snowball Earth Project Data", "url": "https://digital.lib.washington.edu/researchworks/handle/1773/37320"}], "date_created": "Wed, 10 Jul 2013 00:00:00 GMT", "description": "The climatic changes of late Precambrian time, 600-800 million years ago, included episodes of extreme glaciation, during which ice may have covered nearly the entire ocean for several million years, according to the Snowball Earth hypothesis. These episodes would hold an important place in Earth?s evolutionary history; they could have encouraged biodiversity by trapping life forms in small isolated ice-free areas, or they could have caused massive extinctions that cleared the path for new life forms to fill empty niches. What caused the Earth to become iced over, and what later caused the ice to melt? Scientific investigation of these questions will result in greater understanding of the climatic changes that the Earth can experience, and will enable better predictions of future climate. This project involves Antarctic field observations as well as laboratory studies and computer modeling.\u003cbr/\u003e\u003cbr/\u003eThe aim of this project is not to prove or disprove the Snowball Earth hypothesis but rather to quantify processes that are important for simulating snowball events in climate models. The principal goal is to identify the types of ice that would have been present on the frozen ocean, and to determine how much sunlight they would reflect back to space. Reflection of sunlight by bright surfaces of snow and ice is what would maintain the cold climate at low latitudes. The melting of the ocean required buildup of greenhouse gases, but it was probably aided by deposition of desert dust and volcanic ash darkening the snow and ice. With so much ice on the Earth?s surface, even small differences in the amount of light that the ice absorbed or reflected could cause significant changes in climate. The properties of the ice would also determine where, and in what circumstances, photosynthetic life could have survived. Some kinds of ice that are rare on the modern Earth may have been pivotal in allowing the tropical ocean to freeze. The ocean surfaces would have included some ice types that now exist only in Antarctica: bare cold sea ice with precipitated salts, and \"blue ice\" areas of the Transantarctic Mountains that were exposed by sublimation and have not experienced melting. Field expeditions were mounted to examine these ice types, and the data analysis is underway. A third ice type, sea ice with a salt crust, is being studied in a freezer laboratory. Modeling will show how sunlight would interact with ice containing light-absorbing dust and volcanic ash. Aside from its reflection of sunlight, ice on the Snowball ocean would have been thick enough to flow under its own weight, invading all parts of the ocean. Yet evidence for the survival of photosynthetic life indicates that some regions of liquid water were maintained at the ocean surface. One possible refuge for photosynthetic organisms is a bay at the far end of a nearly enclosed tropical sea, formed by continental rifting and surrounded by desert, such as the modern Red Sea. A model of glacier flow is being developed to determine the dimensions of the channel, connecting the sea to the ocean, necessary to prevent invasion by the flowing ice yet maintain a water supply to replenish evaporation.", "east": 168.0, "geometry": "POINT(162.5 -77)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -76.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Warren, Stephen; Light, Bonnie; Campbell, Adam; Carns, Regina; Dadic, Ruzica; Mullen, Peter; Brandt, Richard; Waddington, Edwin D.", "platforms": "Not provided", "repo": "PI website", "repositories": "PI website", "science_programs": null, "south": -78.0, "title": "Ocean Surfaces on Snowball Earth", "uid": "p0000402", "west": 157.0}, {"awards": "0739743 Bay, Ryan", "bounds_geometry": "POINT(123.35 -75.1)", "dataset_titles": "Dome C optical logging data", "datasets": [{"dataset_uid": "000234", "doi": "", "keywords": null, "people": null, "repository": "PI website", "science_program": null, "title": "Dome C optical logging data", "url": "http://icecube.berkeley.edu/~bay/edc99/"}], "date_created": "Wed, 27 Jun 2012 00:00:00 GMT", "description": "Bay 0739743\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to make high-resolution logs of dust and ash in the Dome C borehole using an optical dust logger. Logging at 20-50 cm/sec, in a matter of hours, mm-scale depth resolution of dust concentration and volcanic ash layers over the entire 3270 m borehole back to ~800 ka can be provided. The logger probes an area of order m2 of the horizon compared to the ~0.02 m2 core, greatly suppressing depositional noise and making the technique immune to core damage or loss. The method achieves unprecedented resolution of climate variations for matching or comparing ice core records, can detect particulate layers from explosive fallout which are invisible or missing in the core, and often reveals subtle trend changes which can elude standard core analyses. With the highly resolved dust record, it is expected to find new synchronous age markers between East Antarctica, West Antarctica and Greenland. The data could be instrumental in unifying global climate records, or resolving mysteries such as the transition from 41-kyr glacial cycles to apparent 100-kyr cycles. The project will extend previous finding, which make the most convincing case to date for a causal relationship between explosive volcanic events and abrupt climate change on millennial timescales. A search will also be made for evidence that some of the worldwide explosive fallout events that have been identified may have resulted from impacts by comets or asteroids. The investigators will evaluate the reliability of terrestrial impact crater records and the possibility that Earth impacts are considerably more frequent than is generally appreciated. Better understanding of the factors which force abrupt climate changes, the recurrence rate and triggering mechanisms of large volcanic eruptions, and the frequency of Gt to Tt-energy bolide impacts are of vital interest for civilization. The work plan for 2008-11 comprises modifying and testing of existing hardware in year one; logging field work, most likely in year two; data analysis and publication of results in year three. Because the EPICA collaborators will provide a suitable logging winch onsite, the logistical needs of this project are modest and can be accommodated by Twin Otter from McMurdo. The proposal is in the spirit of the International Polar Year (IPY) by forging an international collaboration with potential societal benefit. The project will provide interdisciplinary training to students and postdoctoral fellows from the U.S. and other countries.", "east": 123.35, "geometry": "POINT(123.35 -75.1)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e OPTICAL DUST LOGGERS", "is_usap_dc": false, "keywords": "Ash Layer; LABORATORY; Not provided; FIELD INVESTIGATION; Climate; Antarctica; Ice Core; Bolides; Borehole; Climate Change; Paleoclimate; FIELD SURVEYS; Volcanic", "locations": "Antarctica", "north": -75.1, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bay, Ryan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "PI website", "repositories": "PI website", "science_programs": null, "south": -75.1, "title": "Dust Logging at Dome C for Abrupt Climate Changes, Large Volcanic Eruptions and Bolide Impacts", "uid": "p0000717", "west": 123.35}, {"awards": "9726186 Pilskaln, Cynthia", "bounds_geometry": null, "dataset_titles": "Expedition data of NBP0101", "datasets": [{"dataset_uid": "002641", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0101", "url": "https://www.rvdata.us/search/cruise/NBP0101"}, {"dataset_uid": "002580", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0101", "url": "https://www.rvdata.us/search/cruise/NBP0101"}], "date_created": "Thu, 03 Mar 2011 00:00:00 GMT", "description": "This proposed work is a study of the biological production and export flux of biogenic matter in response to ventilation of intermediate and deep water masses within the Polar Front zone. It is a collaborative work between the University of Maine and the Chinese Antarctic Research Expedition (CHINARE). The shipboard work is proposed for the Chinese antarctic resupply vessel off Prydz Bay in the Indian Ocean sector. In the austral Spring, this region experiences phytoplankton blooms that are thought to be the result of nutrient transport by the ventilation of intermediate and deep water masses. On an annual basis, it is believed that such blooms are the primary source of particulate organic carbon and biogenic silica flux to the ocean bottom. At this time however no data exists on the amount of particulate organic matter that sinks through the water column, leaving the quantitative relationships between production and export largely undefined in this region. The initial phase of the work consists of setting out a time-series sediment trap mooring at approximately 64 deg S latitude and 73 deg E longitude to take advantage of the historical data set that CHINARE has obtained in this area over the past decade. The biweekly to monthly trap samples will be analyzed for their organic constituents, and in conjunction with primary productivity observations will provide the basic data from which export values can be derived. This work will be carried out in collaboration with the State Oceanic Administration of the People\u0027s Republic of China, and the Chinese Antarctic Research Expedition. In addition to providing time on the antarctic resupply vessel, the SOA will sponsor the shipboard primary productivity experiments and the supporting hydrographic measurements. The collaborating American scientists will provide guidance in making these observations to standards developed for the Joint Global Ocean Flux Study, and provide the hardware for the moored sediment trap. There will be a mutual sharing between the U.S. and Chinese investigators of all samples and data sets, and the data analysis will be carried out jointly. ***", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS", "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Leventer, Amy", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "POC Production and Export in the Indian Ocean Sector of the Southern Ocean: A US-China Collaborative Research Program", "uid": "p0000800", "west": null}, {"awards": "0538097 Anandakrishnan, Sridhar", "bounds_geometry": "POLYGON((140 -89.8,144 -89.8,148 -89.8,152 -89.8,156 -89.8,160 -89.8,164 -89.8,168 -89.8,172 -89.8,176 -89.8,180 -89.8,180 -89.82,180 -89.84,180 -89.86,180 -89.88,180 -89.9,180 -89.92,180 -89.94,180 -89.96,180 -89.98,180 -90,176 -90,172 -90,168 -90,164 -90,160 -90,156 -90,152 -90,148 -90,144 -90,140 -90,140 -89.98,140 -89.96,140 -89.94,140 -89.92,140 -89.9,140 -89.88,140 -89.86,140 -89.84,140 -89.82,140 -89.8))", "dataset_titles": "IRIS Data Management Center (DMC) holds the full resolution seismic data. Keyword: POLELAKE. Dataset ID: 10-019; seismic data. Keyword: POLELAKE. Dataset ID: 10-019", "datasets": [{"dataset_uid": "000102", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "seismic data. Keyword: POLELAKE. Dataset ID: 10-019", "url": "http://ds.iris.edu/ds/nodes/dmc/"}, {"dataset_uid": "001466", "doi": "", "keywords": null, "people": null, "repository": "IRIS", "science_program": null, "title": "IRIS Data Management Center (DMC) holds the full resolution seismic data. Keyword: POLELAKE. Dataset ID: 10-019", "url": "http://www.iris.edu/dms/dmc"}], "date_created": "Wed, 08 Sep 2010 00:00:00 GMT", "description": "0538097\u003cbr/\u003eAnandakrishnan\u003cbr/\u003e\u003cbr/\u003eThis award supports a project to intensively study a subglacial Antarctic lake near the geographic South Pole using seismic and radar methods. These ground-based experiments are better suited to determine the presence of water and its thickness than are airborne methods. We hypothesize that there are two end-member explanations for this feature: either the lake is thawed, but freezing on (and likely to have been freezing on through much of the current interglacial period), or it is a frozen, relict lake for which the high basal radar reflectivity is due to intergranular water in a permafrost-like layer beneath the ice. The seismic experiment we propose is ideally suited to examine these alternatives. Intermediate cases of, e.g., a thawed saturated sedimentary base or a smooth crystalline basement layer would also be resolved by this experiment. Seismic reflections are sensitive to changes in acoustic impedance which is strongly variable with fluid content, porosity, and lithology. Water has low density relative to most rocks and low seismic velocity (and nil shear wave velocity) relative to both ice and rock. Thus, discriminating between subglacial water and subglacial rock is a task ideally suited to the seismic reflection technique. This project has significant impacts outside the directly affected fields of Antarctic glaciology and geology. The lake (either thawed or sediments with thin liquid layers around the matrix particles) will have the potential for harboring novel life forms. The experiment has the potential for expanding our information about the newest frontier in life on Earth. The collaboration between PIs in the seismic community and the marine acoustics community will foster cross-disciplinary pollination of ideas, techniques, and tools. In addition to traditional seismic techniques, new methods of data analysis that have been developed by acousticians will be applied to this problem as an independent measure of lake properties. We will train students who will have a wider view of seismology than would be possible in a traditional ocean acoustics or traditional geoscience seismology program of study.", "east": 180.0, "geometry": "POINT(160 -89.9)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e SEISMIC REFLECTION PROFILERS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOGRAPHS; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e SEISMOMETERS \u003e SEISMOMETERS", "is_usap_dc": false, "keywords": "Antarctica; South Pole; Porosity; Not provided; Seismic; Lithology; FIELD INVESTIGATION; Subglacial; Subglacial Lake; FIELD SURVEYS; LABORATORY; Fluid Content; Acoustic Impedance", "locations": "Antarctica; South Pole", "north": -89.8, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Anandakrishnan, Sridhar; Holland, Charles", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS; Not provided; OTHER \u003e PHYSICAL MODELS \u003e LABORATORY", "repo": "IRIS", "repositories": "IRIS", "science_programs": null, "south": -90.0, "title": "Characterization of Lake Amundsen-Scott, S. Pole: A Ground Geophysical Program", "uid": "p0000693", "west": 140.0}, {"awards": "9117721 Jeffries, Martin", "bounds_geometry": "POLYGON((-110.149 -52.353,-104.86076 -52.353,-99.57252 -52.353,-94.28428 -52.353,-88.99604 -52.353,-83.7078 -52.353,-78.41956 -52.353,-73.13132 -52.353,-67.84308 -52.353,-62.55484 -52.353,-57.2666 -52.353,-57.2666 -54.17539,-57.2666 -55.99778,-57.2666 -57.82017,-57.2666 -59.64256,-57.2666 -61.46495,-57.2666 -63.28734,-57.2666 -65.10973,-57.2666 -66.93212,-57.2666 -68.75451,-57.2666 -70.5769,-62.55484 -70.5769,-67.84308 -70.5769,-73.13132 -70.5769,-78.41956 -70.5769,-83.7078 -70.5769,-88.99604 -70.5769,-94.28428 -70.5769,-99.57252 -70.5769,-104.86076 -70.5769,-110.149 -70.5769,-110.149 -68.75451,-110.149 -66.93212,-110.149 -65.10973,-110.149 -63.28734,-110.149 -61.46495,-110.149 -59.64256,-110.149 -57.82017,-110.149 -55.99778,-110.149 -54.17539,-110.149 -52.353))", "dataset_titles": "Expedition Data", "datasets": [{"dataset_uid": "002253", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9405"}, {"dataset_uid": "002283", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/NBP9305"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This project is an examination of the physical and structural properties of the antarctic ice pack in the Amundsen, Bellingshausen, and Ross Seas, with the goal of defining the geographical variability of various ice types, the deformation processes that are active in the antarctic ice pack, and the large-scale thermodynamics and heat exchange processes of the ice- covered Southern Ocean. An additional goal is to relate specific characteristics of antarctic sea ice to its synthetic aperture radar (SAR) signature as observed from satellites. Physical properties include the salinity, temperature, and brine volumes, while structural properties include the fraction of frazil, platelet, and congelation ice of the seasonal antarctic pack ice. Differences in ice types are the result of differences in the environment in which the ice forms: frazil ice is formed in supercooled sea water, normally through wind or wave-induced turbulence, while platelet and congelation ice is formed under quiescent conditions. The fraction of frazil ice (which has been observed to be generally in excess of 50% in Weddell Sea ice floes) is an important variable in the energy budget of the upper ocean, and contributes significantly to the stabilization of the surface layers. The integration of sea ice field observations and synthetic aperture radar data analysis and modeling studies will contribute to a better understanding of sea ice parameters and their geophysical controls, and will be useful in defining the kind of air-ice-ocean interactions that can be studied using SAR data, as well as having broader relevance and application to atmospheric, biological, and oceanographic investigations of the Southern Ocean.", "east": -57.2666, "geometry": "POINT(-83.7078 -61.46495)", "instruments": null, "is_usap_dc": false, "keywords": "R/V NBP", "locations": null, "north": -52.353, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Jeffries, Martin", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -70.5769, "title": "Sea Ice Physical-Structrual Characteristics: Development and SAR Signature in the Pacific Sector of the Southern Ocean", "uid": "p0000647", "west": -110.149}, {"awards": "0636706 Sivjee, Gulamabas", "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": "NCAR Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) Data System ID# 5700 (full data link not provided)", "datasets": [{"dataset_uid": "000137", "doi": "", "keywords": null, "people": null, "repository": "NCAR", "science_program": null, "title": "NCAR Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) Data System ID# 5700 (full data link not provided)", "url": "http://cedarweb.hao.ucar.edu/"}], "date_created": "Thu, 23 Oct 2008 00:00:00 GMT", "description": "This project will provide for the continued operation and data analysis of an electro-optical remote sensing facility at South Pole Station. The facility will be used to examine 1) the source(s) and propagation of patches of enhanced plasma density in the F-region of the Antarctic ionosphere, 2) changes in the Antarctic E-region O/N2 ratio in the center of the night-sector of the auroral oval and compare the ratios with those found in the sun-aligned auroral arcs in the Polar Cap region, 3) Antarctic middle atmosphere disturbances generated by Stratospheric Warming Events (SWE), 4) quantitative characterization of the effects of solar variability on the temperature of the upper mesosphere region, 5) Antarctic thermospheric response to Solar Magnetic Cloud/Coronal Mass Ejection (SMC/CME) events, and 6) the effects of Joule heating on the thermodynamics of the Antarctic F-region. Data for all these studies will come from two sets of remote-sensing facilities at SPS: 1) Auroral emissions brightness measurements from the sun-synchronous Meridian Scanning Photon Counting Multichannel photometer; 2) Airglow and Auroral emission spectra recorded continuously during Austral winter at SPS with the high throughput, high resolution Infrared Michelson Interferometer as well as Visible - Near Infrared CCD spectrographs. \u003cbr/\u003e\u003cbr/\u003eMeridional variations in the brightness of F-region\u0027s auroral emissions provide the necessary data for investigations of the dynamics and IMF control, as well as the excitation mechanism(s), of the F-region patches. The brightness of auroral emissions from O and N relative to those from molecular species (O2 and N2) can be analyzed to assess, quantitatively, changes in the thermospheric composition. These data (from continuous (24 hours a day) measurements during the totally dark six months of each Austral winter at SPS) will be used to investigate the effects of solar-terrestrial disturbances on Antarctic thermospheric composition and thermodynamics, including response of the mesopause to solar cycle variations. Changes in airglow temperature (derived from OH and O2 bands), from different mesosphere/lower-thermosphere (MLT) heights, permit studies of the dynamical effects of Planetary, Tidal and Gravity waves propagating in the MLT regions as well as non-linear interactions among these waves. Coupling of different atmospheric regions over SPS, through enhanced gravity wave activities during SWE that lead to a precursor as Mesospheric cooling, will be investigated through the observed changes in MLT kinetic air temperature and density. \u003cbr/\u003e\u003cbr/\u003eThe project will enhance the infrastructure for research and education at Embry-Riddle Aeronautical University, bringing together the PI/Co-I and students from Departments of Physical Sciences and Aerospace Engineering. Graduate and undergraduate students will participate in modern research and software development.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Astrophysics and Geospace Sciences", "paleo_time": null, "persons": "Gulamabas, Sivjee; Azeem, Syed", "platforms": "Not provided", "repo": "NCAR", "repositories": "NCAR", "science_programs": null, "south": -90.0, "title": "Observations of Upper Atmospheric Energetics, Dynamics, and Long-Term Variations over the South Pole Station", "uid": "p0000292", "west": -180.0}, {"awards": "0088047 Bell, Robin", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Tue, 03 Jan 2006 00:00:00 GMT", "description": "0088047\u003cbr/\u003eBell\u003cbr/\u003e\u003cbr/\u003eThis award supports a two year project to address fundamental questions about the mass and energy flux through Lake Vostok, a subglacial lake in East Antarctica, sealed beneath almost 4 kilometers of ice. The project will involve developing lake circulation models, complemented by the analysis of new ice penetrating radar data over the lake and surrounding regions. This project will help to accurately define the regions of melting and freezing within the lake and help to provide an improved estimate of the form of the lake. The combined data analysis and modeling effort will provide a critical framework for developing international plans to sample the waters of Lake Vostok for biota and to recover sediments from Lake Vostok for paleoclimate studies.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": false, "keywords": "Paleoclimate; Circulation Models; Lake Vostok; Data Analysis; Subglacial; Modeling; Not provided", "locations": "Lake Vostok", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bell, Robin; Tremblay, Bruno; Hohmann, Roland; Clarke, Garry; Studinger, Michael S.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Mass and Energy Fluxes Through Lake Vostok: Observations and Models", "uid": "p0000093", "west": null}, {"awards": "9909167 Rust, David", "bounds_geometry": "POLYGON((-180 -62.83,-144 -62.83,-108 -62.83,-72 -62.83,-36 -62.83,0 -62.83,36 -62.83,72 -62.83,108 -62.83,144 -62.83,180 -62.83,180 -65.547,180 -68.264,180 -70.981,180 -73.698,180 -76.415,180 -79.132,180 -81.849,180 -84.566,180 -87.283,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87.283,-180 -84.566,-180 -81.849,-180 -79.132,-180 -76.415,-180 -73.698,-180 -70.981,-180 -68.264,-180 -65.547,-180 -62.83))", "dataset_titles": "Solar Magnetograms and Filtergrams", "datasets": [{"dataset_uid": "600022", "doi": "", "keywords": null, "people": "Rust, David M.", "repository": "USAP-DC", "science_program": null, "title": "Solar Magnetograms and Filtergrams", "url": "https://www.usap-dc.org/view/dataset/600022"}], "date_created": "Wed, 19 Oct 2005 00:00:00 GMT", "description": "This award provides funding for one year of data analysis of the solar images produced by the Flare Genesis Experiment telescope during a long-duration balloon flight over Antarctica in early 2000, near the peak of solar activity for this solar cycle. The telescope produced many thousands of images and maps of solar magnetic fields with unprecedented resolution. It is expected that the detailed analysis of the data will improve understanding of how energy stored in solar magnetic fields is converted to high temperatures and velocities associated with solar activity. \u003cbr/\u003e\u003cbr/\u003eThis project is jointly supported by NASA, NSF/OPP and NSF/ATM.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": -62.83, "nsf_funding_programs": "Antarctic Ocean and Atmospheric Sciences", "paleo_time": null, "persons": "Rust, David M.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Flare Genesis Experiment", "uid": "p0000245", "west": -180.0}]

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