USAP-DC

{"dp_type": "Project", "free_text": "Taylor Valley"}

[{"awards": "2137378 Varsani, Arvind; 2137377 Bergstrom, Anna; 2137375 Schmidt, Steven; 2137376 Porazinska, Dorota", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Wed, 10 May 2023 00:00:00 GMT", "description": "Cryoconite holes are sediment-filled melt holes in the surface of glaciers that can be important sites of active microbial life in an otherwise mostly frozen and barren landscape. Previous studies in the McMurdo Dry Valleys, Antarctica suggest that viral infections of microbes, and a general lack of fertilizers (i.e., nutrients), may be important factors shaping the development and functioning of microbial communities in cryoconite holes. The researchers propose an experimental approach to understand how nutrient limitation affects diversity (number of species) and overall abundance of microbes, and how the diversity and abundance of microbes in turn affects the diversity, abundance, and infection type of viruses that parasitize the microbes in cryoconite sediments. The researchers will use sediments previously collected from Antarctic glaciers that have varying concentrations of viruses and nutrients, to set up a nutrient-addition experiment to determine how nutrients affect microbial and viral population dynamics. The results will deepen our understanding of how microbial communities in general are shaped by nutrients and viruses and give new insights into the functioning of viruses in extremely cold environments. The researchers will publish their findings in scientific journals and will share their discoveries with K-12 students from rural schools in collaboration with the Pinhead Institute and will connect undergraduate students from under-represented minorities to polar research through participation in the universitys Science, Technology, Engineering \u0026 Mathematics Routes Uplift Research Program. Outreach will be achieved through videos produced and distributed by a professional science communicator. The research advances a National Science Foundation goal of expanding fundamental knowledge of Antarctic systems, biota, and processes by utilizing the unique characteristics of the Antarctic region as a science observing platform. \r\n\r\nThe Principal Investigators propose an experimental approach to understand how nutrient limitation affects microbial diversity and abundances and their cascading effects on virus diversity, abundance, and mode of infection (lysis vs. lysogeny) in Antarctic cryoconite holes. Cryoconite holes are ideal natural microcosms for manipulative studies, not available in other cryospheric ecosystems. The PIs will use previously collected cryoconite from across a gradient of both viral diversity and nutrient levels to address questions about key limiting nutrients and microbial-viral community dynamics in cryoconite sediments. Nutrient manipulation experiments will be conducted in a growth chamber that closely approximates the light and temperature regime of in situ cryoconite holes to test three core hypotheses: (1) phosphorus availability limits microbial productivity and abundance in cryoconite holes; (2) relaxing nutrient limitation in cryoconite from low-diversity glaciers will increase species diversity, leading microbial communities to resemble those found on more nutrient-rich glaciers; (3) relaxing nutrient limitation will increase the diversity and abundance of viruses by increasing the availability of suitable hosts, and decrease the prevalence of lysogenic infections. By manipulating nutrient limitation within a realistic range, this project will help verify hypothesized phosphorus limitation of Antarctic cryoconite holes and will extend understanding of the connections between nutrients, diversity, and viral infection dynamics in the cryosphere more generally. A better understanding of these dynamics in cryoconite sediments improves the ability of scientists to forecast future impacts of environmental changes in the cryosphere.\r\n\r\nThis award reflects NSF\u0027\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027\u0027s intellectual merit and broader impacts review criteria.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "AQUATIC ECOSYSTEMS; Taylor Valley", "locations": "Taylor Valley", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Varsani, Arvind; Porazinska, Dorota; Schmidt, Steven; Bergstrom, Anna", "platforms": null, "repositories": null, "science_programs": null, "south": null, "title": "Collaborative Research: Role of Nutrient Limitation and Viral Interactions on Antarctic Microbial Community Assembly: A Cryoconite Microcosm Study", "uid": "p0010418", "west": null}, {"awards": "1937546 Morgan-Kiss, Rachael; 1937595 Briggs, Brandon", "bounds_geometry": "POLYGON((162 -77.616667,162.1 -77.616667,162.2 -77.616667,162.3 -77.616667,162.4 -77.616667,162.5 -77.616667,162.6 -77.616667,162.7 -77.616667,162.8 -77.616667,162.9 -77.616667,163 -77.616667,163 -77.6283336,163 -77.6400002,163 -77.6516668,163 -77.6633334,163 -77.67500000000001,163 -77.68666660000001,163 -77.69833320000001,163 -77.7099998,163 -77.7216664,163 -77.733333,162.9 -77.733333,162.8 -77.733333,162.7 -77.733333,162.6 -77.733333,162.5 -77.733333,162.4 -77.733333,162.3 -77.733333,162.2 -77.733333,162.1 -77.733333,162 -77.733333,162 -77.7216664,162 -77.7099998,162 -77.69833320000001,162 -77.68666660000001,162 -77.67500000000001,162 -77.6633334,162 -77.6516668,162 -77.6400002,162 -77.6283336,162 -77.616667))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 27 Jul 2022 00:00:00 GMT", "description": " Microbial communities are of more than just a scientific curiosity. Microbes represent the single largest source of evolutionary and biochemical diversity on the planet. They are the major agents for cycling carbon, nitrogen, phosphorus, and other elements through the ecosystem. Despite their importance in ecosystem function, microbes are still generally overlooked in food web models and nutrient cycles. Moreover, microbes do not live in isolation: their growth and metabolism are influenced by complex interactions with other microorganisms. This project will focus on the ecology, activity and roles of microbial communities in Antarctic Lake ecosystems. The team will characterize the genetic underpinnings of microbial interactions and the influence of environmental gradients (e.g. light, nutrients, oxygen, sulfur) and seasons (e.g. summer vs. winter) on microbial networks in Lake Fryxell and Lake Bonney in the Taylor Valley within the McMurdo Dry Valley region. Finally, the project furthers the NSF goals of training new generations of scientists by including undergraduate and graduate students, a postdoctoral researcher and a middle school teacher in both lab and field research activities. This partnership will involve a number of other outreach training activities, including visits to classrooms and community events, participation in social media platforms, and webinars. \u003cbr/\u003e\u003cbr/\u003ePart II: Technical description: Ecosystem function in the extreme Antarctic Dry Valleys ecosystem is dependent on complex biogeochemical interactions between physiochemical environmental factors (e.g. light, nutrients, oxygen, sulfur), time of year (e.g. summer vs. winter) and microbes. Microbial network complexity can vary in relation to specific abiotic factors, which has important implications on the fragility and resilience of ecosystems under threat of environmental change. This project will evaluate the influence of biogeochemical factors on microbial interactions and network complexity in two Antarctic ice-covered lakes. The study will be structured by three main objectives: 1) infer positive and negative interactions from rich spatial and temporal datasets and investigate the influence of biogeochemical gradients on microbial network complexity using a variety of molecular approaches; 2) directly observe interactions among microbial eukaryotes and their partners using flow cytometry, single-cell sorting and microscopy; and 3) develop metabolic models of specific interactions using metagenomics. Outcomes from amplicon sequencing, meta-omics, and single-cell genomic approaches will be integrated to map specific microbial network complexity and define the role of interactions and metabolic activity onto trends in limnological biogeochemistry in different seasons. These studies will be essential to determine the relationship between network complexity and future climate conditions. Undergraduate researchers will be recruited from both an REU program with a track record of attracting underrepresented minorities and two minority-serving institutions. To further increase polar literacy training and educational impacts, the field team will include a teacher as part of a collaboration with the successful NSF-funded PolarTREC program and participation in activities designed for public outreach.\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": 163.0, "geometry": "POINT(162.5 -77.67500000000001)", "instruments": null, "is_usap_dc": true, "keywords": "MICROALGAE; AQUATIC ECOSYSTEMS; Antarctica; LAKE/POND; BACTERIA/ARCHAEA; COMMUNITY DYNAMICS", "locations": "Antarctica", "north": -77.616667, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Morgan-Kiss, Rachael; Briggs, Brandon", "platforms": null, "repositories": null, "science_programs": null, "south": -77.733333, "title": "ANT LIA: Collaborative Research: Genetic Underpinnings of Microbial Interactions in Chemically Stratified Antarctic Lakes", "uid": "p0010355", "west": 162.0}, {"awards": "2046260 Salvatore, Mark; 2045880 Sokol, Eric", "bounds_geometry": "POLYGON((161.88 -77.47,162.075 -77.47,162.27 -77.47,162.465 -77.47,162.66 -77.47,162.855 -77.47,163.05 -77.47,163.245 -77.47,163.44 -77.47,163.635 -77.47,163.83 -77.47,163.83 -77.501,163.83 -77.532,163.83 -77.563,163.83 -77.594,163.83 -77.625,163.83 -77.656,163.83 -77.687,163.83 -77.718,163.83 -77.749,163.83 -77.78,163.635 -77.78,163.44 -77.78,163.245 -77.78,163.05 -77.78,162.855 -77.78,162.66 -77.78,162.465 -77.78,162.27 -77.78,162.075 -77.78,161.88 -77.78,161.88 -77.749,161.88 -77.718,161.88 -77.687,161.88 -77.656,161.88 -77.625,161.88 -77.594,161.88 -77.563,161.88 -77.532,161.88 -77.501,161.88 -77.47))", "dataset_titles": null, "datasets": null, "date_created": "Thu, 21 Apr 2022 00:00:00 GMT", "description": "Part I: Non-technical description: \r\nWater is life and nowhere is it more notable than in deserts. Within the drylands on Earth, the Antarctic deserts, represented in this study by the McMurdo Dry Valleys, exemplify life in extreme environments with scarce water, low temperatures and long periods of darkness during the polar winter. There is a scarcity of methods to determine water availability, data necessary to predict which species are successful in the drylands, unless measurements are done manually or with field instruments. This project aims to develop a remote method of determining soil moisture and use the new data to identify locations suitable for life. Combining these habitats with known species distributions in the McMurdo Dry Valleys, results from this project will predict which species should be present, and also what is the expected species distribution in a changing environment. In this way the project takes advantage of a combination of methods, from recent remote sensing products, ecological models and 30 years of field collections to bring a prediction of how life might change in the McMurdo Dry Valleys in a warmer, and possibly, moister future climate. This project benefits the National Science Foundation goals of expanding fundamental knowledge of Antarctic biota and the processes that sustain life in extreme environments. The knowledge acquired in this project will be disseminated to other drylands through training in high-school curricular programming in Native American communities of the Southwest U.S. \r\nPart II: Technical description: \r\nTerrestrial environments in Antarctica are characterized by low liquid water supply, sub-zero temperatures and the polar night in winter months. During summer, melting of snow patches, seasonal steams from glacial melt and vicinity to lakes provide a variety of environments that maintain life, not yet studied at landscape-scale level for habitat suitability and the processes that drive them. This project proposes to integrate remote sensing, hydrological models and ecological models to establish habitat suitability for species in the McMurdo Dry Valleys based on water availability. The approach is at a landscape level in order to establish present-day and future scenarios of species distribution. There are four main objectives: remote sensing development of moisture levels in soils, combining biological and soil data, building and calibrating models of habitat suitability by combining species distribution and environmental variability and applying statistical species distribution model. The field data needed to develop habitat suitability and calibration of models will leverage a the 30-year dataset collected by the McMurdo Long-Term Ecological Research program. Mechanistic models developed will be essential to predict species distribution in future climate scenarios. Training of post-doctoral researchers and a graduate student will prepare for the next generation of Antarctic scientists. Results from this project will train high-school students from Native American communities in the Southwestern U.S., where similar desert conditions exist.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 163.83, "geometry": "POINT(162.855 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "ACTIVE LAYER; Taylor Valley; USAP-DC; Amd/Us; AMD; MODELS; USA/NSF", "locations": "Taylor Valley", "north": -77.47, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Salvatore, Mark; Gooseff, Michael N.; Sokol, Eric; Barrett, John", "platforms": "OTHER \u003e MODELS \u003e MODELS", "repositories": null, "science_programs": null, "south": -77.78, "title": "Collaborative Research: Moving Beyond the Margins: Modeling Water Availability and Habitable Terrestrial Ecosystems in the Polar Desert of the McMurdo Dry Valleys", "uid": "p0010316", "west": 161.88}, {"awards": "1946326 Doran, Peter", "bounds_geometry": "POLYGON((161 -77.4,161.3 -77.4,161.6 -77.4,161.9 -77.4,162.2 -77.4,162.5 -77.4,162.8 -77.4,163.1 -77.4,163.4 -77.4,163.7 -77.4,164 -77.4,164 -77.46,164 -77.52,164 -77.58,164 -77.64,164 -77.7,164 -77.76,164 -77.82,164 -77.88,164 -77.94,164 -78,163.7 -78,163.4 -78,163.1 -78,162.8 -78,162.5 -78,162.2 -78,161.9 -78,161.6 -78,161.3 -78,161 -78,161 -77.94,161 -77.88,161 -77.82,161 -77.76,161 -77.7,161 -77.64,161 -77.58,161 -77.52,161 -77.46,161 -77.4))", "dataset_titles": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: Infrared Stimulated Luminescence data; EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: in situ 14C data", "datasets": [{"dataset_uid": "601520", "doi": "10.15784/601520", "keywords": "Antarctica; Sample/collection Description; Sample/Collection Description; Sample Location; Taylor Valley", "people": "Doran, Peter; Stone, Michael", "repository": "USAP-DC", "science_program": "LTER", "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: Infrared Stimulated Luminescence data", "url": "https://www.usap-dc.org/view/dataset/601520"}, {"dataset_uid": "601521", "doi": "10.15784/601521", "keywords": "Antarctica; Carbon-14; Sample/collection Description; Sample/Collection Description; Sample Location; Taylor Valley", "people": "Doran, Peter; Stone, Michael", "repository": "USAP-DC", "science_program": null, "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers: in situ 14C data", "url": "https://www.usap-dc.org/view/dataset/601521"}], "date_created": "Mon, 31 Jan 2022 00:00:00 GMT", "description": "The closed basin lakes of Taylor Valley fluctuate in lake level, responding to the net balance of water gain and loss. Geomorphologic evidence suggests that past lake levels in Taylor Valley were once much higher than they are today. Past studies have largely targeted organic radiocarbon as a means for dating these past lake levels. However, an unconstrained radiocarbon reservoir effect in the region reduces the credibility of those data and the lake level chronologies they produce. Alternative geochronometers are therefore necessary to validify or augment the lake level records produced using organic radiocarbon. This research tests the overarching hypothesis that a multi-proxy geochronologic approach can constrain the timing of major changes in Taylor Valley lake levels. The goals of this study are to provide a coarse-scale absolute chronology for lake level fluctuation in Taylor Valley in order to test the validity of the lake level record hypothesized by the organic radiocarbon datasets, demonstrate that in situ 14C and OSL are effective means to understand the physical dynamics of ancient water bodies, and increase the current understanding of polar lacustrine and ice sheet responses to past and present climatic changes. ", "east": 164.0, "geometry": "POINT(162.5 -77.7)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Amd/Us; Taylor Valley; AGE DETERMINATIONS; USA/NSF; AMD; USAP-DC", "locations": "Taylor Valley", "north": -77.4, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Earth Sciences", "paleo_time": null, "persons": "Doran, Peter", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LTER", "south": -78.0, "title": "EAGER: Refining glacial lake history in Taylor Valley, East Antarctica with alternative geochronometers", "uid": "p0010294", "west": 161.0}, {"awards": "1847067 Levy, Joseph", "bounds_geometry": "POLYGON((161 -76,161.35 -76,161.7 -76,162.05 -76,162.4 -76,162.75 -76,163.1 -76,163.45 -76,163.8 -76,164.15 -76,164.5 -76,164.5 -76.2,164.5 -76.4,164.5 -76.6,164.5 -76.8,164.5 -77,164.5 -77.2,164.5 -77.4,164.5 -77.6,164.5 -77.8,164.5 -78,164.15 -78,163.8 -78,163.45 -78,163.1 -78,162.75 -78,162.4 -78,162.05 -78,161.7 -78,161.35 -78,161 -78,161 -77.8,161 -77.6,161 -77.4,161 -77.2,161 -77,161 -76.8,161 -76.6,161 -76.4,161 -76.2,161 -76))", "dataset_titles": "Biogeochemical measurements of water tracks and adjacent dry soils from the McMurdo Dry Valleys; Surface Water Geochemistry from the McMurdo Dry Valleys", "datasets": [{"dataset_uid": "601684", "doi": "10.15784/601684", "keywords": "Antarctica; Cation Exchange; Chemistry:soil; Chemistry:Soil; Dry Valleys; Organic Matter; Salt; Soil", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Biogeochemical measurements of water tracks and adjacent dry soils from the McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601684"}, {"dataset_uid": "601703", "doi": "10.15784/601703", "keywords": "Antarctica; Dry Valleys", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Surface Water Geochemistry from the McMurdo Dry Valleys", "url": "https://www.usap-dc.org/view/dataset/601703"}], "date_created": "Fri, 24 Dec 2021 00:00:00 GMT", "description": "Antarctic groundwater drives the regional carbon cycle, accelerates permafrost thaw, and shapes Antarctic climate response. However, groundwater extent, movement, and processes on a continent virtually locked in ice are poorly understood. The proposed work investigates the interplay between groundwater, sediment, and ice in Antarctica\u2019s cold desert landscapes to determine when, where, and why Antarctic groundwater is flowing, and how quickly it will switch Antarctic frozen deserts from dry and stable to wet and disintegrating. Little is known about the extent, chemistry, and duration of groundwater in Antarctic seasonal wetlands. Mapping the changing extent of Antarctic wetlands requires the ability to measure soil moisture rapidly and repeatedly and over large areas. Changing groundwater extent will be captured through an unmanned aerial vehicle (UAV)-based mapping approach. The project integrates a diverse range of sensors with new UAV technologies to provide a higher-resolution and more frequent assessment of Antarctic groundwater extent and composition than can be accomplished using satellite observations alone. To complement the research objectives, the PI will develop a new UAV summer field school, the Geosciences UAV Academy, focused on training undergraduate-level UAV pilots in conducting novel Earth science research using cutting edge imaging tools. The integration of research and technology will prepare students for careers in burgeoning UAV-related industries and research. The project will deliver new UAV tools and workflows for soil moisture mapping relevant to arid regions common not just to Antarctica but to temperate desert and dryland systems and will train student research pilots to tackle next generation airborne challenges. \r\n\r\nWater tracks are the basic hydrological unit that currently feeds the rapidly-changing polar and permafrost wetlands in the Antarctic McMurdo Dry Valleys (MDV). Despite the importance of water tracks in the MDV hydrologic cycle and their influence on biogeochemistry, little is known about how these water tracks control the unique brine processes operating in Antarctic ice-free areas. Both groundwater availability and geochemistry shape Antarctic microbial communities, connecting soil geology and hydrology to carbon cycling and ecosystem functioning. The objectives of this CAREER proposal are to 1) map water tracks to determine the spatial distribution and seasonal magnitude of groundwater impacts on the MDV near-surface environment to determine how water tracks drive irreversible permafrost thaw, how water tracks enhance chemical weathering and biogeochemical cycling, and how water tracks integrate and accelerate climate feedbacks between terrestrial Antarctic soils and the Southern Ocean; 2) establish a UAV academy training earth sciences students to answer geoscience questions using drone-based platforms and remote sensing techniques; and 3) provide a formative step in the development of the PI as a teacher-scholar. UAV-borne hyperspectral imaging complemented with field soil sampling will determine the aerial extent and timing of inundation, water level, and water budget of representative water tracks in the MDV. Soil moisture will be measured via near-infrared reflectance spectroscopy while bulk chemistry of soils and groundwater will be analyzed via ion chromatography and soil x-ray fluorescence. Sedimentological and hydrological properties (suction/matric potential, hydraulic conductivity, etc.) will be determined via analysis of intact core samples. These data will be used to test competing hypotheses regarding the origin of water track solutions and water movement through seasonal wetlands. The will provide a regional understanding of Antarctic groundwater sources, groundwater flux, and the influence of regional hydrogeology on solute export to the Southern Ocean and on soil/atmosphere linkages in earth\u2019s carbon budget. The UAV school will 1) provide comprehensive instruction at the undergraduate level in both how and why UAVs can be used in geoscience research and learning; and 2) provide a long-term piece of educational infrastructure in the form of an ultimately self-sustaining summer program for undergraduate UAV education. \r\n", "east": 164.5, "geometry": "POINT(162.75 -77)", "instruments": null, "is_usap_dc": true, "keywords": "FIELD SURVEYS; Amd/Us; USA/NSF; AMD; USAP-DC; FROZEN GROUND; Taylor Valley", "locations": "Taylor Valley", "north": -76.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Levy, Joseph", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0, "title": "Linking Antarctic Cold Desert Groundwater to Thermokarst \u0026 Chemical Weathering in Partnership with the Geoscience UAV Academy", "uid": "p0010286", "west": 161.0}, {"awards": "1744785 Barrett, John", "bounds_geometry": "POLYGON((-180 -77.62,-145.683 -77.62,-111.366 -77.62,-77.049 -77.62,-42.732 -77.62,-8.415 -77.62,25.902 -77.62,60.219 -77.62,94.536 -77.62,128.853 -77.62,163.17 -77.62,163.17 -77.618,163.17 -77.616,163.17 -77.614,163.17 -77.612,163.17 -77.61,163.17 -77.608,163.17 -77.606,163.17 -77.604,163.17 -77.602,163.17 -77.6,128.853 -77.6,94.536 -77.6,60.219 -77.6,25.902 -77.6,-8.415 -77.6,-42.732 -77.6,-77.049 -77.6,-111.366 -77.6,-145.683 -77.6,180 -77.6,178.319 -77.6,176.638 -77.6,174.957 -77.6,173.276 -77.6,171.595 -77.6,169.914 -77.6,168.233 -77.6,166.552 -77.6,164.871 -77.6,163.19 -77.6,163.19 -77.602,163.19 -77.604,163.19 -77.606,163.19 -77.608,163.19 -77.61,163.19 -77.612,163.19 -77.614,163.19 -77.616,163.19 -77.618,163.19 -77.62,164.871 -77.62,166.552 -77.62,168.233 -77.62,169.914 -77.62,171.595 -77.62,173.276 -77.62,174.957 -77.62,176.638 -77.62,178.319 -77.62,-180 -77.62))", "dataset_titles": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica", "datasets": [{"dataset_uid": "200260", "doi": "doi:10.6073/pasta/9acbbde9abc1e013f8c9fd9c383327f4", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica", "url": "https://doi.org/10.6073/pasta/9acbbde9abc1e013f8c9fd9c383327f4"}], "date_created": "Tue, 30 Nov 2021 00:00:00 GMT", "description": "This package contains data collected from microbial mat surveys (i.e., percent cover, ash-free dry mass (AFDM), and pigment concentrations \u2013 chlorophyll-a, scytonemin, and carotenoids) associated with satellite-derived Normalized Difference Vegetation Index (NDVI) values from the Lake Fryxell Basin of Taylor Valley, located in the McMurdo Dry Valleys of Antarctica. The purpose of this study was to quantitatively compare key microbial mat characteristics to NDVI. Data were collected at seven plot locations within the Canada Glacier Antarctic Specially Protected Area (ASPA) near Canada Stream, as well as alongside Green Creek and McKnight Creek. NDVI values were derived from a WorldView-2 multispectral satellite image taken of the Lake Fryxell Basin on January 19, 2018, while biological ground surveying and sampling were conducted during the 2nd and 4th weeks of January 2018. ", "east": 163.19, "geometry": "POINT(-16.82 -77.61)", "instruments": null, "is_usap_dc": true, "keywords": "AMD; ECOSYSTEM FUNCTIONS; FIELD SURVEYS; USAP-DC; USA/NSF; Taylor Valley; Amd/Us", "locations": "Taylor Valley", "north": -77.6, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Barrett, John; Salvatore, Mark", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -77.62, "title": "Collaborative Research: Remote characterization of microbial mats in Taylor Valley, Antarctica through in situ sampling and spectral validation", "uid": "p0010281", "west": 163.17}, {"awards": "1644171 Blackburn, Terrence", "bounds_geometry": "POLYGON((162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163.2 -77.5,163.4 -77.5,163.6 -77.5,163.8 -77.5,164 -77.5,164 -77.525,164 -77.55,164 -77.575,164 -77.6,164 -77.625,164 -77.65,164 -77.675,164 -77.7,164 -77.725,164 -77.75,163.8 -77.75,163.6 -77.75,163.4 -77.75,163.2 -77.75,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,162 -77.725,162 -77.7,162 -77.675,162 -77.65,162 -77.625,162 -77.6,162 -77.575,162 -77.55,162 -77.525,162 -77.5))", "dataset_titles": "Isotopic ratios for subglacial precipitates from East Antarctica", "datasets": [{"dataset_uid": "200240", "doi": "10.26022/IEDA/111548 ", "keywords": null, "people": null, "repository": "EarthChem", "science_program": null, "title": "Isotopic ratios for subglacial precipitates from East Antarctica", "url": "https://doi.org/10.26022/IEDA/111548"}], "date_created": "Fri, 13 Aug 2021 00:00:00 GMT", "description": "The primary scientific goal of the proposed project is to test whether Taylor Valley, Antarctica has experienced glacial incision in the last ~1 million years in spite of cold climate conditions. One of the Dry Valleys of the Transantarctic Mountains, Taylor Valley exhibits over 2000 m of relief from sub sea-level troughs to high polar peaks. The Dry Valleys are characterized by low mean annual temperatures, paucity of precipitation and erosion that has allowed fragile glacial landforms, now subaerially exposed at high elevations, to be preserved for as long as 15 Ma. Two end member models can explain the timing of glacial incision and the observation that Quaternary advances of Taylor Glacier have left deposits at lower valley elevations with each advance. In the first scenario, all Valley relief is generated prior to 15 Ma when non-polar climates enabled warm-based glaciers to incise and widen fluvial channels more so than peaks. In this case, Quaternary drift deposits record advances of cold-based glaciers of decreasing ice volume. Limited glacial erosion and silt generation results in drift deposits composed primarily of recycled sediments. In the second scenario, selective erosion of the valley floor continues to deepen Taylor Valley over the last 2 Ma while high elevation peaks remain uneroded in polar conditions. The \u2018bathtub rings\u2019 of Quaternary drifts reaching a progressively lower elevation through time could be due to the lowering of the valley floor by subglacial erosion and with it, production of silt which is now incorporated into these drifts. While either scenario would result in the present day topography, they differ in the implied evolution of regional glacial ice volume over time and the timing of both valley relief production and generation of fine-grained particles. Here we propose to distinguish between these two models, by placing time constrains on fine particle production using U-series comminution dating. This new geochronologic tool exploits the loss of 234U due to alpha-recoil. The deficiency in 234U only becomes detectable in particles with a sufficiently high surface-area-to-volume ratio which can incur appreciable 234U loss (\u003c50 \uf0ecm). The timing of comminution and particle size controls the magnitude of 234U loss, up to 10% in silt-sized particles comminuted over 1.5 million years ago. And while this geochronologic tool is in its infancy, the scientific goal of this proposal can be achieved by resolving between ancient and recently comminuted fine particles, a binary question that our preliminary modeling and measured data show is readily resolved.", "east": 164.0, "geometry": "POINT(163 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "ICE SHEETS; Taylor Valley", "locations": "Taylor Valley", "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Blackburn, Terrence; Tulaczyk, Slawek", "platforms": null, "repo": "EarthChem", "repositories": "EarthChem", "science_programs": null, "south": -77.75, "title": "U-Series Comminution Age Constraints on Taylor Valley Erosion", "uid": "p0010243", "west": 162.0}, {"awards": "1543344 Soreghan, Gerilyn", "bounds_geometry": null, "dataset_titles": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "datasets": [{"dataset_uid": "601599", "doi": "10.15784/601599", "keywords": "Antarctica; Anza Borrego; Iceland; Mcmurdo Dry Valleys; Norway; Peru; Puerto Rico; Taylor Valley; Washington; Wright Valley", "people": "Demirel-Floyd, Cansu", "repository": "USAP-DC", "science_program": null, "title": "Data and metadata for \"Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems\"", "url": "https://www.usap-dc.org/view/dataset/601599"}], "date_created": "Tue, 18 May 2021 00:00:00 GMT", "description": "As glaciers creep across the landscape, they can act as earthmovers, plucking up rocks and grinding them into fine sediments. Glaciers have moved across the Antarctic landscape over thousands to millions of years, leaving these ground-up sediments in their wake. This study builds on pilot discoveries by the investigators that revealed remarkably large and variable measurements of surface area in glacially-derived fine-grained sediments found in the McMurdo Dry Valleys (MDV), one of the few landscapes on the Antarctic continent not currently covered by ice. Surface area is key to chemical weathering, the process by which rock is converted to soils as ions are carried away in streams and groundwater. These chemical weathering processes are also one of the primary means by which the Earth system naturally removes carbon dioxide from the atmosphere. Hence, high surface areas observed in sediments implies high \"weatherability\" which in turn translates to more potential carbon dioxide removed from the atmosphere. Therefore, chemical weathering in high surface area glacial sediments may have significant impacts on Earth\u0027s carbon cycle. The researchers will measure the chemical and physical properties of sediments previously collected from the Dry Valleys to understand what factors lead to production of sediment with high-surface area and potential \"weather ability\" and investigate how sediment produced in these glacial systems could ultimately impact Earth\u0027s carbon budget. Results from this research will help scientists (including modelers) refine predictions of the effects of melting glaciers- and attendant exposure of glacial sediment? on atmospheric carbon levels. These results may also contribute to applied research efforts on development of carbon-dioxide removal technologies utilizing principles of rock weathering. In addition to the scientific benefits, this research will involve several students at the undergraduate, graduate, and post-doctoral levels, including science education undergraduates, thus contributing to training of the next-generation STEM workforce.\r\n\r\nPhysical weathering produces fresh surfaces, greatly enhancing specific surface area (SSA) and reactive surface area (RSA) of primary minerals. Quantifying SSA and RSA of sediments is key to determining dissolution and leaching rates during natural weathering, but few data exist on distribution of sediment SA, particularly in glacial and fluvial systems. Pilot data from glacial stream systems in Taylor Valley and Wright Valley (located in the MDV) exhibit remarkably high and variable values in both SSA and RSA, values that in some cases greatly exceed values from muds in temperate glacial systems. This discovery motivates the current research, which aims to investigate the hypothesis that high and variable SAs of muds within Wright and Taylor Valleys reflect textural and/or compositional inheritance from the differing depositional settings within the MDV, biologic controls, dust additions, and/or pedogenic processes. These hypotheses will be tested by sedimentologically, mineralogically, and geochemically characterizing muds from glacially derived sediment deposited in various environments (cold vs. wet based glaciation; fluvial, lacustrine, dust, and drift deposits) and of varying age (Miocene to Modern) from the MDV and quantifying variation of SA and reactivity. Comparisons with analyzed muds from temperate glacial systems will enable polar-temperate comparisons. Analyses will focus on muds of previously collected sediment from the MDVs. Grain size and SSA will be measured by Laser Analysis and N2 adsorption BET, respectively. After carbonate removal, samples will be re-analyzed for SSA, and muds characterized geochemically. Mineralogy and bulk chemistry will also be assessed on co-occurring sand fractions, and textural attributes documented. SSA-normalized dissolution experiments will be used to compare solutes released from sediments to determine RSAs. Results will be integrated with the various sedimentologic and geochemical analyses to test the posed hypotheses. Ultimately, this research should shed light on how weathering in Antarctic systems contributes to global carbon cycling.", "east": null, "geometry": null, "instruments": null, "is_usap_dc": true, "keywords": "USAP-DC; AMD; FIELD INVESTIGATION; USA/NSF; Dry Valleys; SEDIMENT CHEMISTRY; Amd/Us; Antarctica; Weathering", "locations": "Antarctica; Dry Valleys", "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Soreghan, Gerilyn; Elwood Madden, Megan", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Quantifying surface area in muds from the Antarctic Dry Valleys: Implications for weathering in glacial systems", "uid": "p0010181", "west": null}, {"awards": "1745053 Salvatore, Mark; 1744849 Sokol, Eric; 1744785 Barrett, John", "bounds_geometry": "POLYGON((162.92 -77.56,162.971 -77.56,163.022 -77.56,163.073 -77.56,163.124 -77.56,163.175 -77.56,163.226 -77.56,163.277 -77.56,163.328 -77.56,163.379 -77.56,163.43 -77.56,163.43 -77.571,163.43 -77.582,163.43 -77.593,163.43 -77.604,163.43 -77.615,163.43 -77.626,163.43 -77.637,163.43 -77.648,163.43 -77.659,163.43 -77.67,163.379 -77.67,163.328 -77.67,163.277 -77.67,163.226 -77.67,163.175 -77.67,163.124 -77.67,163.073 -77.67,163.022 -77.67,162.971 -77.67,162.92 -77.67,162.92 -77.659,162.92 -77.648,162.92 -77.637,162.92 -77.626,162.92 -77.615,162.92 -77.604,162.92 -77.593,162.92 -77.582,162.92 -77.571,162.92 -77.56))", "dataset_titles": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica, January 2018", "datasets": [{"dataset_uid": "200344", "doi": "10.6073/pasta/9acbbde9abc1e013f8c9fd9c383327f4", "keywords": null, "people": null, "repository": "EDI", "science_program": null, "title": "McMurdo Dry Valleys LTER: Microbial mat biomass and Normalized Difference Vegetation Index (NDVI) values from Lake Fryxell Basin, Antarctica, January 2018", "url": "https://portal.edirepository.org/nis/mapbrowse?packageid=knb-lter-mcm.263.1"}], "date_created": "Wed, 03 Jul 2019 00:00:00 GMT", "description": "Microbial mats are found throughout the McMurdo Dry Valleys where summer snowmelt provides liquid water that allows these mats to flourish. Researchers have long studied the environmental conditions microbial mats need to grow. Despite these efforts, it has been difficult to develop a broad picture of these unique ecosystems. Recent advances in satellite technology now provide researchers an exciting new tool to study these special Antarctic ecosystems from space using the unique spectral signatures associated with microbial mats. This new technology not only offers the promise that microbial mats can be mapped and studied from space, this research will also help protect these delicate environments from potentially harmful human impacts that can occur when studying them from the ground. This project will use satellite imagery and spectroscopic techniques to identify and map microbial mat communities and relate their properties and distributions to both field and lab-based measurements. This research provides an exciting new tool to help document and understand the distribution of a major component of the Antarctic ecosystem in the McMurdo Dry Valleys.\r\n\r\nThe goal of this project is to establish quantitative relationships between spectral signatures derived from orbit and the physiological status and biogeochemical properties of microbial mat communities in Taylor Valley, Antarctica, as measured by field and laboratory analyses on collected samples. The goal will be met by (1) refining atmospheric correction techniques using in situ radiometric rectification to derive accurate surface spectra; (2) collecting multispectral orbital images concurrent with in situ sampling and spectral measurements in the field to ensure temporal comparability; (3) measuring sediment, water, and microbial mat samples for organic and inorganic carbon content, essential biogeochemical nutrients, and chlorophyll-a to determine relevant mat characteristics; and (4) quantitatively associating these laboratory-derived characteristics with field-derived and orbital spectral signatures and parameters. The result of this work will be a more robust quantitative link between the distribution of microbial mat communities and their biogeochemical properties to landscape-scale spectral signatures.\r\n\r\nThis award reflects NSF\u0027s statutory mission and has been deemed worthy of support through evaluation using the Foundation\u0027s intellectual merit and broader impacts review criteria.", "east": 163.43, "geometry": "POINT(163.175 -77.615)", "instruments": null, "is_usap_dc": true, "keywords": "RIVERS/STREAM; CYANOBACTERIA (BLUE-GREEN ALGAE); USAP-DC; Taylor Valley; INFRARED IMAGERY; WORLDVIEW-2; WORLDVIEW-3; Antarctica; FIELD INVESTIGATION; Amd/Us; ACTIVE LAYER", "locations": "Antarctica; Taylor Valley", "north": -77.56, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Salvatore, Mark; Barrett, John; Sokol, Eric", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e WORLDVIEW \u003e WORLDVIEW-2; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e WORLDVIEW \u003e WORLDVIEW-3", "repo": "EDI", "repositories": "EDI", "science_programs": null, "south": -77.67, "title": "COLLABORATIVE RESEARCH: Remote Characterization of Microbial Mats in Taylor Valley, Antarctica, through In Situ Sampling and Spectral Validation", "uid": "p0010036", "west": 162.92}, {"awards": "1246342 Fountain, Andrew; 1245749 Levy, Joseph; 1246203 Gooseff, Michael", "bounds_geometry": "POLYGON((160.105465 -77.2119,160.7907435 -77.2119,161.476022 -77.2119,162.1613005 -77.2119,162.846579 -77.2119,163.5318575 -77.2119,164.217136 -77.2119,164.9024145 -77.2119,165.587693 -77.2119,166.2729715 -77.2119,166.95825 -77.2119,166.95825 -77.3189628,166.95825 -77.4260256,166.95825 -77.5330884,166.95825 -77.6401512,166.95825 -77.747214,166.95825 -77.8542768,166.95825 -77.9613396,166.95825 -78.0684024,166.95825 -78.1754652,166.95825 -78.282528,166.2729715 -78.282528,165.587693 -78.282528,164.9024145 -78.282528,164.217136 -78.282528,163.5318575 -78.282528,162.846579 -78.282528,162.1613005 -78.282528,161.476022 -78.282528,160.7907435 -78.282528,160.105465 -78.282528,160.105465 -78.1754652,160.105465 -78.0684024,160.105465 -77.9613396,160.105465 -77.8542768,160.105465 -77.747214,160.105465 -77.6401512,160.105465 -77.5330884,160.105465 -77.4260256,160.105465 -77.3189628,160.105465 -77.2119))", "dataset_titles": "2014-2015 lidar survey of the McMurdo Dry Valleys, Antarctica; Active Layer Temperatures from Crescent Stream banks, Taylor Valley Antarctica", "datasets": [{"dataset_uid": "000209", "doi": "", "keywords": null, "people": null, "repository": "OpenTopo", "science_program": null, "title": "2014-2015 lidar survey of the McMurdo Dry Valleys, Antarctica", "url": "http://opentopo.sdsc.edu/datasetMetadata?otCollectionID=OT.112016.3294.1"}, {"dataset_uid": "601075", "doi": "10.15784/601075", "keywords": "Antarctica; Dry Valleys; Glaciology; Paleoclimate; Permafrost; Soil Temperature; Taylor Valley", "people": "Gooseff, Michael N.", "repository": "USAP-DC", "science_program": null, "title": "Active Layer Temperatures from Crescent Stream banks, Taylor Valley Antarctica", "url": "https://www.usap-dc.org/view/dataset/601075"}], "date_created": "Wed, 20 Dec 2017 00:00:00 GMT", "description": "Collaborative Research: THE MCMURDO DRY VALLEYS: A Landscape on the Threshold of Change is supported by the Antarctic Integrated System Science (AISS) program in the Antarctic Sciences Section of the Division of Polar Programs within the Geosciences Directorate of the National Sciences Foundation (NSF). The funds will support the collection of state-of-the-art high resolution LIDAR (combining the terms light and radar) imagery of the Dry Valleys of Antarctica in the 2014/2015 Antarctic field season, with LIDAR data collection and processing being provided by the NSF-supported NCALM (National Center for Airborne Laser Mapping) facility. LIDAR images collected in 2014/2015 will be compared to images from 2001 in order to detect decadal change. Additional fieldwork will look at the distribution of buried massive ice, and the impacts that major changes like slumping are having on the biota. All field data will be used to improve models on energy balance, and hydrology.\u003cbr/\u003e\u003cbr/\u003eIntellectual Merit: There have been dramatic changes over the past decade in the McMurdo Dry Valleys: rivers are incising by more than three meters, and thermokarst slumps are appearing near several streams and lakes. These observations have all been made by researchers in the field, but none of the changes have been mapped on a valley-wide scale. This award will provide a new baseline map for the entire Dry Valley system, with high-resolution imagery provided for the valley floors, and lower resolution imagery available for the higher elevation areas that are undergoing less change. The project will test the idea that sediment-covered ice is associated with the most dramatic changes, due to differential impacts of the increased solar radiation on sediment-covered compared to clean ice, and despite the current trend of slightly cooling air temperatures within the Dry Valleys. Information collected on the topography, coupled with the GPR determined buried ice distributions, will also be incorporated into improved energy and hydrological models. In addition to providing the new high-resolution digital elevation model (DEM), the project will ultimately result in identification of areas that are susceptible to sediment-enhanced melt-driven change, providing a powerful prediction tool for the impacts of climate change.\u003cbr/\u003e\u003cbr/\u003eBroader Impacts: The new DEM will be immediately useful to a wide range of disciplines, and will provide a comprehensive new baseline against which future changes will be compared. The project will provide a tool for the whole community to use, and the investigators will work with the community to make them aware of the new assets via public presentations, and perhaps via a workshop. The map will have international interest, and will also serve as a tool for environmental managers to draw on as they consider conservation plans. Several undergraduate and graduate students will participate in the project, and one of the co-PIs is a new investigator. The imagery collected is expected to be of interest to the general public in addition to scientific researchers, and venues for outreach such as museum exhibits and the internet will be explored. The proposed work is synergistic with 1) the co-located McMurdo LTER program, and 2) the NCALM facility that is also funded by the Geosciences Directorate.", "east": 166.95825, "geometry": "POINT(163.5318575 -77.747214)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e LIDAR/LASER ALTIMETERS \u003e AIRBORNE LASER SCANNER", "is_usap_dc": true, "keywords": "USAP-DC; Antarctica; Not provided; LANDFORMS; NOT APPLICABLE", "locations": "Antarctica", "north": -77.2119, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science; Antarctic Integrated System Science", "paleo_time": null, "persons": "Levy, Joseph; Gooseff, Michael N.; Fountain, Andrew", "platforms": "Not provided; OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "OpenTopo", "repositories": "OpenTopo; USAP-DC", "science_programs": null, "south": -78.282528, "title": "Collaborative Research: THE MCMURDO DRY VALLEYS: A landscape on the Threshold of Change", "uid": "p0000076", "west": 160.105465}, {"awards": "1341284 Swanger, Kate", "bounds_geometry": "POLYGON((161 -77.5,161.2 -77.5,161.4 -77.5,161.6 -77.5,161.8 -77.5,162 -77.5,162.2 -77.5,162.4 -77.5,162.6 -77.5,162.8 -77.5,163 -77.5,163 -77.525,163 -77.55,163 -77.575,163 -77.6,163 -77.625,163 -77.65,163 -77.675,163 -77.7,163 -77.725,163 -77.75,162.8 -77.75,162.6 -77.75,162.4 -77.75,162.2 -77.75,162 -77.75,161.8 -77.75,161.6 -77.75,161.4 -77.75,161.2 -77.75,161 -77.75,161 -77.725,161 -77.7,161 -77.675,161 -77.65,161 -77.625,161 -77.6,161 -77.575,161 -77.55,161 -77.525,161 -77.5))", "dataset_titles": null, "datasets": null, "date_created": "Mon, 09 Oct 2017 00:00:00 GMT", "description": "Paragraph for Laypersons:\u003cbr/\u003eThis research focuses on the history of rock glaciers and buried glacial ice in the McMurdo Dry Valleys region of Antarctica. Rock glaciers are flowing mixtures of ice and sediments common throughout alpine and high-latitude regions on Earth and Mars. Despite similar appearances, rock glaciers can form under highly variable environmental and hydrological conditions. The main research questions addressed here are: 1) what environmental and climatological conditions foster long-term preservation of rock glaciers in Antarctica, 2) what role do rock glaciers play in Antarctic landscape evolution and the local water cycle, and 3) what can rock glaciers reveal about the extent and timing of previous glacial advances? The project will involve two Antarctic field seasons to image the interior of Antarctic rock glaciers using ground-penetrating radar, to gather ice cores for chemical analyses, and to gather surface sediments for dating. The Dry Valleys host the world?s southernmost terrestrial ecosystem (soil, stream and lake micro-organisms and mosses); rock glaciers and ground-ice are an important and poorly-studied source of meltwater and nutrients for these ecosystems. This research will shed light on the glacial and hydrological history of the Dry Valleys region and the general environmental conditions the foster rock glaciers, features that generally occur in warmer and/or wetter locations. The research will provide support for five graduate/undergraduate students, who will actively gather data in the field, followed by interpretation, dissemination and presentation of the data. Additionally, the researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities. A series of time-lapse images of hydrological processes, and videos of researchers in the field, will serve as a dramatic centerpiece in community and school presentations.\u003cbr/\u003e\u003cbr/\u003eParagraph for Scientific Community:\u003cbr/\u003eRock glaciers are common in the McMurdo Dry Valleys, but are concentrated in a few isolated regions: western Taylor Valley, western Wright Valley, Pearse Valley and Bull Pass. The investigators hypothesize that the origin and age of these features varies by region: that rock glaciers in Pearse and Taylor valley originated as buried glacier ice, whereas rock glaciers in Wright Valley formed through permafrost processes, such as mobilization of ice-rich talus. To address these hypotheses, the project will: 1) develop relative and absolute chronologies for the rock glaciers through field mapping and optically stimulated luminescence dating of overlying sediments, 2) assess the origin of clean-ice cores through stable isotopic analyses, and 3) determine if present-day soil-moisture and temperature conditions are conducive to rock glacier formation/preservation. The proposed research will provide insight into the spatial and temporal distribution of buried glacier ice and melt-water-derived ground ice in the McMurdo Dry Valleys, with implications for glacial history, as well as the potential role of rock glaciers in the regional hydrologic cycle (and the role of ground-ice as a source for moisture and nutrient for local ecosystems). The project will provide general constraints on the climatic and hydrologic conditions that foster permafrost rock glaciers, features that generally occur under warmer and wetter conditions than those found in the present-day McMurdo Dry Valleys. The application of OSL and cosmogenic exposure\u003cbr/\u003edating is novel to rock glaciers, geomorphic features that have proven difficult to date, despite their ubiquity in Antarctica and their potential scientific importance. The research will provide support for five graduate/undergraduate students, who will participate in the field work, followed by interpretation, dissemination and presentation of the data. The researchers will participate in a range of educational activities including outreach with local K-12 in the Lowell, MA region, such as summer workshops and classroom visits with hands-on activities.", "east": 163.0, "geometry": "POINT(162 -77.625)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Swanger, Kate", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.75, "title": "Origin and Climatic Significance of Rock Glaciers in the McMurdo Dry Valleys: Assessing Spatial and Temporal Variability", "uid": "p0000297", "west": 161.0}, {"awards": "1245580 Castro, M. Clara", "bounds_geometry": "POINT(162.167 -77.733)", "dataset_titles": "Developing a New Paleoclimate Proxy for Polar and Alpine Glacial Regions Based on Noble Gases", "datasets": [{"dataset_uid": "600389", "doi": "10.15784/600389", "keywords": "Antarctica; Atmosphere; Chemistry:fluid; Chemistry:Fluid; Critical Zone; Geochemistry; Noble Gas; Paleoclimate; Ross Ice Shelf; Ross Sea; Taylor Valley", "people": "Castro, M. Clara", "repository": "USAP-DC", "science_program": null, "title": "Developing a New Paleoclimate Proxy for Polar and Alpine Glacial Regions Based on Noble Gases", "url": "https://www.usap-dc.org/view/dataset/600389"}], "date_created": "Mon, 30 Jan 2017 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eNoble gases in groundwater systems can indicate past climates in ice-free regions through estimation of noble gas temperatures. Traditional noble gas temperatures cannot be derived in ice-covered regions where water is not in contact with the atmosphere. The goal of the proposed work is to take advantage of noble gas properties in ice covered lakes at the ice/water interface to develop a new paleoclimate proxy with the potential to be routinely used in both polar and alpine glacial regions. The evolution of the Taylor Valley lakes is intimately connected to the dynamics of nearby glaciers, as well as the advance and retreat of the Ross Ice Shelf, both of which are dictated by climate change. The perennial ice cover of the lakes form at the water/ice interface and sublimate at the top rendering these lakes ideal to test and develop this new proxy. The proposed research involves conducting an extensive noble gas sampling campaign of lake water, stream water, ice covers and glacial ice. This data set, together with data continuously collected in the area will provide a solid basis to develop, test and refine mathematical models capable of accurately describing heavy noble gas concentration profiles as well as their overall inventory in the lakes over time. These will provide information on the occurrence of major climatic events while simultaneously providing temporal constraints on such events. \u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eThe findings of this work will be inserted into a new class that the PI has created at the University of Michigan targeted at non-science majors. It will create research opportunities for 1-2 undergraduates each year and will support a PhD student. The outcomes of this research could have strong societal relevance.", "east": 162.167, "geometry": "POINT(162.167 -77.733)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.733, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Castro, M. Clara; Doran, Peter; Kenig, Fabien", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.733, "title": "Developing a New Paleoclimate Proxy for Polar and Alpine Glacial Regions Based on Noble Gases", "uid": "p0000388", "west": 162.167}, {"awards": "1343649 Levy, Joseph", "bounds_geometry": "POLYGON((162.852 -77.6111,162.9893 -77.6111,163.1266 -77.6111,163.2639 -77.6111,163.4012 -77.6111,163.5385 -77.6111,163.6758 -77.6111,163.8131 -77.6111,163.9504 -77.6111,164.0877 -77.6111,164.225 -77.6111,164.225 -77.65331,164.225 -77.69552,164.225 -77.73773,164.225 -77.77994,164.225 -77.82215,164.225 -77.86436,164.225 -77.90657,164.225 -77.94878,164.225 -77.99099,164.225 -78.0332,164.0877 -78.0332,163.9504 -78.0332,163.8131 -78.0332,163.6758 -78.0332,163.5385 -78.0332,163.4012 -78.0332,163.2639 -78.0332,163.1266 -78.0332,162.9893 -78.0332,162.852 -78.0332,162.852 -77.99099,162.852 -77.94878,162.852 -77.90657,162.852 -77.86436,162.852 -77.82215,162.852 -77.77994,162.852 -77.73773,162.852 -77.69552,162.852 -77.65331,162.852 -77.6111))", "dataset_titles": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "datasets": [{"dataset_uid": "600139", "doi": "10.15784/600139", "keywords": "Antarctica; Chemistry:soil; Chemistry:Soil; Critical Zone; Dry Valleys; Permafrost; Sample/collection Description; Sample/Collection Description; Well Measurements", "people": "Levy, Joseph", "repository": "USAP-DC", "science_program": null, "title": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600139"}], "date_created": "Mon, 05 Oct 2015 00:00:00 GMT", "description": "Intellectual Merit: \u003cbr/\u003eThe PIs propose to quantify the hillslope water, solute, and carbon budgets for Taylor Valley in the McMurdo Dry Valleys, using water tracks to investigate near-surface geological processes and challenge the paradigm that shallow groundwater is minimal or non-exixtant. Water tracks are linear zones of high soil moisture that route shallow groundwater downslope in permafrost dominated soils. Four hypotheses will be tested: 1) water tracks are important pathways for water and solute transport; 2) water tracks transport more dissolved silica than streams in Taylor Valley indicating they are the primary site of chemical weathering for cold desert soils and bedrock; 3) water tracks that drain highland terrains are dominated by humidity-separated brines while water tracks that drain lowland terrains are dominated by marine aerosols; 4) water tracks are the sites of the highest terrestrial soil carbon concentrations and the strongest CO2 fluxes in Taylor Valley and their carbon content increases with soil age, while carbon flux decreases with age. To test these hypotheses the PIs will carry out a suite of field measurements supported by modeling and remote sensing. They will install shallow permafrost wells in water tracks that span the range of geological, climatological, and topographic conditions in Taylor Valley. Multifrequency electromagnetic induction sounding of the upper ~1 m of the permafrost will create the first comprehensive map of soil moisture in Taylor Valley, and will permit direct quantification of water track discharge across the valley. The carbon contents of water track soils will be measured and linked to global carbon dynamics.\u003cbr/\u003e\u003cbr/\u003eBroader impacts: \u003cbr/\u003eNon-science majors at Oregon State University will be integrated into the proposed research through a new Global Environmental Change course focusing on the scientific method in Antarctica. Three undergraduate students, members of underrepresented minorities, will be entrained in the research, will contribute to all aspects of field and laboratory science, and will present results at national meetings.", "east": 164.225, "geometry": "POINT(163.5385 -77.82215)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.6111, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Levy, Joseph", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.0332, "title": "Cryptic Hydrology of the McMurdo Dry Valleys: Water Track Contributions to Water and Geochemical Budgets in Taylor Valley, Antarctica", "uid": "p0000407", "west": 162.852}, {"awards": "0631659 Morgan-Kiss, Rachael; 0631494 Priscu, John", "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": "GenBank (NCBI) 18S rRNA genes: GU969060 to GU969102, rbcL genes: GU132860 to GU132939; McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) Program", "datasets": [{"dataset_uid": "000125", "doi": "", "keywords": null, "people": null, "repository": "LTER", "science_program": null, "title": "McMurdo Dry Valleys Long-Term Ecological Research (MCM LTER) Program", "url": "http://www.mcmlter.org/"}, {"dataset_uid": "000126", "doi": "", "keywords": null, "people": null, "repository": "NCBI GenBank", "science_program": null, "title": "GenBank (NCBI) 18S rRNA genes: GU969060 to GU969102, rbcL genes: GU132860 to GU132939", "url": "http://www.ncbi.nlm.nih.gov/genbank/"}], "date_created": "Fri, 08 Oct 2010 00:00:00 GMT", "description": "Data collected on the permanently ice-covered lakes of the McMurdo Dry Valleys (MCM) during the late 1950\u0027s as part of the International Geophysical Year (IGY) showed that they were the only year round liquid water environments on the continent. Organisms in the lakes must possess novel physiological strategies that allow them to survive at low temperature and under extended darkness. Subsequent research has now shown that most organisms in the lakes are not just \"surviving the extremes\" but are actively feeding, growing and reproducing. However, nearly all research on the MCM lakes is restricted to the austral spring and summer when logistical support is provided. The unique aspects of physiological adaptation and metabolic function during the permanently cold and prolonged darkness of the Antarctic winter remain unknown. As part of the \"International Polar Year 2007-2008\" (IPY), the proposed research will study lakes within the Taylor Valley during the transition to polar night to test the overarching hypothesis that the onset of darkness induces a cascade of physiological changes that alters the functional role of autotrophic and heterotrophic microplankton within the lakes. This overarching theme will be addressed through an interdisciplinary study of selected biological components of the lake ecosystems using genomic and physiological tools to understand not only how individual organisms survive, but how they control ecosystem function during this seasonal transition. \u003cbr/\u003e\u003cbr/\u003eThis project is directly relevant to IPY objectives as it addresses a major identified theme (Adaptations to Life in Extreme Cold and Prolonged Darkness) with an international (UK, NZ),\u003cbr/\u003emultidisciplinary team. The research has substantial broader impacts, as it will add to the body of long-term data accumulated by the MCM LTER and MCM Microbial Observatory projects in a synergistic manner; and it will include three undergraduates, a graduate student and two young female investigators. The project is linked to a highly visible education, outreach and human diversity programs supported by the McMurdo LTER, and initiates new outreach programs, including the Passport to Knowledge program.", "east": 180.0, "geometry": "POINT(0 -89.999)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -60.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems; Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Morgan-Kiss, Rachael; Priscu, John; Mikucki, Jill", "platforms": "Not provided", "repo": "LTER", "repositories": "LTER; NCBI GenBank", "science_programs": "LTER", "south": -90.0, "title": "Collaborative Research: IPY- Plankton Dynamics in the McMurdo Dry Valley Lakes During the Transition to Polar Night", "uid": "p0000525", "west": -180.0}, {"awards": "0737168 Prentice, Michael; 0541054 Sletten, Ronald", "bounds_geometry": "POLYGON((162.2335 -77.5047,162.3803 -77.5047,162.5271 -77.5047,162.6739 -77.5047,162.8207 -77.5047,162.9675 -77.5047,163.1143 -77.5047,163.2611 -77.5047,163.4079 -77.5047,163.5547 -77.5047,163.7015 -77.5047,163.7015 -77.52814,163.7015 -77.55158,163.7015 -77.57502,163.7015 -77.59846,163.7015 -77.6219,163.7015 -77.64534,163.7015 -77.66878,163.7015 -77.69222,163.7015 -77.71566,163.7015 -77.7391,163.5547 -77.7391,163.4079 -77.7391,163.2611 -77.7391,163.1143 -77.7391,162.9675 -77.7391,162.8207 -77.7391,162.6739 -77.7391,162.5271 -77.7391,162.3803 -77.7391,162.2335 -77.7391,162.2335 -77.71566,162.2335 -77.69222,162.2335 -77.66878,162.2335 -77.64534,162.2335 -77.6219,162.2335 -77.59846,162.2335 -77.57502,162.2335 -77.55158,162.2335 -77.52814,162.2335 -77.5047))", "dataset_titles": null, "datasets": null, "date_created": "Wed, 06 Oct 2010 00:00:00 GMT", "description": "This award supports a project to examine the stratigraphy of near-surface sediments in Taylor Valley, Antarctica. Two contrasting hypotheses have been proposed for surface sediments in lower Taylor Valley, which have important and very different implications for how the West Antarctic Ice Sheet (WAIS) responded to the sea-level rise of the last deglaciation and Holocene environmental changes. One hypothesis holds that the sediments, designated Ross I drift, directly reflect \u003e10,000 14C-years of WAIS shrinkage in the Ross Sea during and perhaps driven by deglacial sea-level rise. The other hypothesis, holds that the Taylor sediments have little significance for WAIS change during the deglaciation. These two hypotheses reflect fundamentally different interpretations of the sediment record. Over the course of two field seasons and a third year at the home institutions, the project will test these two hypotheses using glacial geology, geochemistry, ground penetrating radar (GPR) at both 100 MHz and 400 MHz, and portable sediment coring. The intellectual merit of the proposed work is that it will test these two hypotheses and make novel use of the subsurface record that may result in new insights into WAIS sensitivity during the deglaciation. The study will also directly test the conclusion that Glacial Lake Washburn was much larger than previously proposed during the Last Glacial Maximum (LGM). This occurrence, if real, represents a stunning climate anomaly. Answers to these local ice sheet and lake questions directly pertain to larger scale issues concerning the influences of sea-level rise, climate change, and internal ice-sheet dynamics on the recession of the WAIS since the LGM. There are numerous broader impacts to this project. Understanding the glacial and lake history in the McMurdo Sound region has important implications for the role that the WAIS will play in future sea-level and global climate change. Moreover, the history of Taylor Valley has significance for the ecosystem studies currently being conducted by the LTER group. Lastly, during the course of the proposed research, the project will train two graduate and undergraduate students and the research will be featured prominently in the teaching of students.", "east": 163.7015, "geometry": "POINT(162.9675 -77.6219)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR", "is_usap_dc": false, "keywords": "Not provided; Salt", "locations": null, "north": -77.5047, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Prentice, Michael; Sletten, Ronald S.", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": -77.7391, "title": "Collaborative Research: Fluctuations of the West Antarctic Ice Sheet in Relation to Lake History in Taylor Valley, Antarctica, Since the Last Glacial Maximum", "uid": "p0000656", "west": 162.2335}, {"awards": "0230276 Ward, Bess", "bounds_geometry": "POLYGON((162 -77.2,162.16 -77.2,162.32 -77.2,162.48 -77.2,162.64 -77.2,162.8 -77.2,162.96 -77.2,163.12 -77.2,163.28 -77.2,163.44 -77.2,163.6 -77.2,163.6 -77.26,163.6 -77.32,163.6 -77.38,163.6 -77.44,163.6 -77.5,163.6 -77.56,163.6 -77.62,163.6 -77.68,163.6 -77.74,163.6 -77.8,163.44 -77.8,163.28 -77.8,163.12 -77.8,162.96 -77.8,162.8 -77.8,162.64 -77.8,162.48 -77.8,162.32 -77.8,162.16 -77.8,162 -77.8,162 -77.74,162 -77.68,162 -77.62,162 -77.56,162 -77.5,162 -77.44,162 -77.38,162 -77.32,162 -77.26,162 -77.2))", "dataset_titles": "What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "datasets": [{"dataset_uid": "600033", "doi": "10.15784/600033", "keywords": "Antarctica; Biota; CTD Data; Dry Valleys; Lake Bonney; Lake Vanda; Microbiology; Taylor Valley", "people": "Ward, Bess", "repository": "USAP-DC", "science_program": null, "title": "What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "url": "https://www.usap-dc.org/view/dataset/600033"}], "date_created": "Sun, 18 Jan 2009 00:00:00 GMT", "description": "Denitrification is the main process by which fixed nitrogen is lost from ecosystems and the regulation of this process may directly affect primary production and carbon cycling over short and long time scales. Previous investigations of the role of bioactive metals in regulating denitrification in bacteria from permanently ice-covered Lake Bonney in the Taylor Valley of East Antarctica indicated that denitrifying bacteria can be negatively affected by metals such as copper, iron, cadmium, lead, chromium, nickel, silver and zinc; and that there is a distinct difference in denitrifying activity between the east and west lobes of the lake. Low iron concentrations were found to exacerbate the potential toxicity of the other metals, while silver has the potential to specifically inhibit denitrification because of its ability to interfere with copper binding in redox proteins, such as nitrite reductase and nitrous oxide reductase. High silver concentrations might prevent the functioning of nitrous oxide reductase in the same way that simple copper limitation does, thereby causing the buildup of nitrous oxide and resulting in a nonfunctional nitrogen cycle. Other factors, such as oxygen concentration, are likely also to affect bacterial activity in Lake Bonney. This project will investigate silver toxicity, general metal toxicity and oxygen concentration to determine their effect on denitrification in the lake by using a suite of \"sentinel\" strains of denitrifying bacteria (isolated from the lake) incubated in Lake Bonney water and subjected to various treatments. The physiological responses of these strains to changes in metal and oxygen concentration will be quantified by flow cytometric detection of single cell molecular probes whose sensitivity and interpretation have been optimized for the sentinel strains. Understanding the relationships between metals and denitrification is expected to enhance our understanding of not only Lake Bonney\u0027s unusual nitrogen cycle, but more generally, of the potential role of metals in the regulation of microbial nitrogen transformations.\u003cbr/\u003e\u003cbr/\u003eThe broader impacts of this work include not only a better understanding of regional biogeochemistry and global perspectives on these processes; but also the training of graduate students and a substantial outreach effort for school children.", "east": 163.6, "geometry": "POINT(162.8 -77.5)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD", "is_usap_dc": true, "keywords": "FIELD SURVEYS", "locations": null, "north": -77.2, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Ward, Bess", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD SURVEYS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.8, "title": "Collaborative Research: What Limits Denitrification and Bacterial Growth in Lake Bonney, Taylor Valley, Antarctica?", "uid": "p0000223", "west": 162.0}, {"awards": "0228052 Kreutz, Karl", "bounds_geometry": "POLYGON((161.0434 -77.3002,161.241645 -77.3002,161.43989 -77.3002,161.638135 -77.3002,161.83638 -77.3002,162.034625 -77.3002,162.23287 -77.3002,162.431115 -77.3002,162.62936 -77.3002,162.827605 -77.3002,163.02585 -77.3002,163.02585 -77.3784846,163.02585 -77.4567692,163.02585 -77.5350538,163.02585 -77.6133384,163.02585 -77.691623,163.02585 -77.7699076,163.02585 -77.8481922,163.02585 -77.9264768,163.02585 -78.0047614,163.02585 -78.083046,162.827605 -78.083046,162.62936 -78.083046,162.431115 -78.083046,162.23287 -78.083046,162.034625 -78.083046,161.83638 -78.083046,161.638135 -78.083046,161.43989 -78.083046,161.241645 -78.083046,161.0434 -78.083046,161.0434 -78.0047614,161.0434 -77.9264768,161.0434 -77.8481922,161.0434 -77.7699076,161.0434 -77.691623,161.0434 -77.6133384,161.0434 -77.5350538,161.0434 -77.4567692,161.0434 -77.3784846,161.0434 -77.3002))", "dataset_titles": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "datasets": [{"dataset_uid": "609399", "doi": "10.7265/N5FF3Q92", "keywords": "Antarctica; Borehole Temperature; Chemistry:ice; Chemistry:Ice; Dry Valleys; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Mass Balance; Paleoclimate; Physical Properties", "people": "Mayewski, Paul A.; Kreutz, Karl", "repository": "USAP-DC", "science_program": null, "title": "Late Holocene Climate Variability, Dry Valleys, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609399"}], "date_created": "Tue, 21 Oct 2008 00:00:00 GMT", "description": "This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit of the project. We plan to collect intermediate-length ice cores (100-200m) at four sites along transects in Taylor Valley and Wright Valley, and analyze each core at high resolution for stable isotopes (d18O, dD), major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, SO42-, MSA), and trace elements (Al, Fe, S, Sr, B). A suite of statistical techniques will be applied to the multivariate glaciochemical dataset to identify chemical associations and to calibrate the time-series records with available instrumental data. Broader impacts of the project include: 1) contributions to several ongoing interdisciplinary Antarctic research programs; 2) graduate and undergraduate student involvement in field, laboratory, and data interpretation activities; 3) use of project data and ideas in several UMaine courses and outreach activities; and 4) data dissemination through peer-reviewed publications, UMaine and other paleoclimate data archive websites, and presentations at national and international meetings.", "east": 163.02585, "geometry": "POINT(162.034625 -77.691623)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MC-ICP-MS; IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e HUMIDITY SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; IN SITU/LABORATORY INSTRUMENTS \u003e TEMPERATURE/HUMIDITY SENSORS \u003e TEMPERATURE SENSORS", "is_usap_dc": true, "keywords": "Holocene; Climate Research; AWS Climate Data; Paleoclimate; Climate Variation; Dry Valleys; Wright Valley; Little Ice Age; Stable Isotopes; Glaciochemical; Ice Core; FIELD INVESTIGATION; Enso; Antarctic Oscillation; Climate; GPS; El Nino-Southern Oscillation; LABORATORY; Not provided; Climate Change; Ice Core Records; Antarctica; Taylor Valley; FIELD SURVEYS; Variability", "locations": "Antarctica; Dry Valleys; Taylor Valley; Wright Valley", "north": -77.3002, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY \u003e HOLOCENE", "persons": "Kreutz, Karl; Arcone, Steven; Mayewski, Paul A.", "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; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.083046, "title": "Dry Valleys Late Holocene Climate Variability", "uid": "p0000155", "west": 161.0434}, {"awards": "0126202 Blankenship, Donald; 0125579 Cuffey, Kurt", "bounds_geometry": "POLYGON((160 -77.6,160.25 -77.6,160.5 -77.6,160.75 -77.6,161 -77.6,161.25 -77.6,161.5 -77.6,161.75 -77.6,162 -77.6,162.25 -77.6,162.5 -77.6,162.5 -77.63,162.5 -77.66,162.5 -77.69,162.5 -77.72,162.5 -77.75,162.5 -77.78,162.5 -77.81,162.5 -77.84,162.5 -77.87,162.5 -77.9,162.25 -77.9,162 -77.9,161.75 -77.9,161.5 -77.9,161.25 -77.9,161 -77.9,160.75 -77.9,160.5 -77.9,160.25 -77.9,160 -77.9,160 -77.87,160 -77.84,160 -77.81,160 -77.78,160 -77.75,160 -77.72,160 -77.69,160 -77.66,160 -77.63,160 -77.6))", "dataset_titles": "Ablation Rates of Taylor Glacier, Antarctica; Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica; Surface Velocities of Taylor Glacier, Antarctica", "datasets": [{"dataset_uid": "609324", "doi": "10.7265/N5RV0KM7", "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Velocity; Taylor Glacier", "people": "Bliss, Andrew; Aciego, Sarah; Cuffey, Kurt M.; Kavanaugh, Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "Surface Velocities of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609324"}, {"dataset_uid": "609326", "doi": "10.7265/N5N29TW8", "keywords": "Ablation Poles; Ablation Rates; Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Taylor Glacier", "people": "Cuffey, Kurt M.; Kavanaugh, Jeffrey; Bliss, Andrew", "repository": "USAP-DC", "science_program": null, "title": "Ablation Rates of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609326"}, {"dataset_uid": "609323", "doi": "10.7265/N5WM1BBZ", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Isotope; Taylor Glacier", "people": "Bliss, Andrew; Aciego, Sarah; Cuffey, Kurt M.; Kavanaugh, Jeffrey", "repository": "USAP-DC", "science_program": null, "title": "Stable Isotopes of Ice on the Surface of Taylor Glacier, Antarctica", "url": "https://www.usap-dc.org/view/dataset/609323"}], "date_created": "Tue, 13 Feb 2007 00:00:00 GMT", "description": "This award supports a project to significantly improve our understanding of how Taylor Glacier flows and responds to climate changes. Taylor Glacier drains the Taylor Dome region of the East Antarctic Ice Sheet and terminates in Taylor Valley, one of the Dry Valleys of Victoria Land. It provides a crucial and unique link between two intensively studied Antarctic environments: the Taylor Dome, from which a 130 kyr ice core paleoclimate record has recently been extracted, and the Dry Valleys, a pivotal Long-Term Ecological Research (LTER) site and a focus of research on geomorphology and glacial geology. The proposed work will thus make an important contribution to ongoing efforts to exploit the Taylor Dome - Dry Valleys system to build a uniquely comprehensive view of regional long-term environmental changes. The proposed work has two complementary components: field research and numerical modelling. Two field seasons will be used to measure velocity, surface strain rate, mass balance, ice thickness, glacier bed reflectance, and subglacial topography, along a nearly complete longitudinal transect of the Taylor Glacier, and along select cross-valley transects. This information will be used to constrain numerical models of ice and heat flow for the Taylor Dome - Taylor Glacier system. These calibrated models will be used to analyze the time-dependent response of the Taylor Glacier to climate changes. The synthesis of results will be aimed to improve understanding of the glacial geomorphology of Taylor Valley, and to illuminate impacts on the Taylor Valley lakes ecosystem. The project will have a major role in furthering the careers of a doctoral-level graduate student and a post-doctoral researcher.", "east": 162.5, "geometry": "POINT(161.25 -77.75)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS RECEIVERS; IN SITU/LABORATORY INSTRUMENTS \u003e SPECTROMETERS/RADIOMETERS \u003e MASS SPECTROMETERS", "is_usap_dc": true, "keywords": "Glacier; Glacier Surface; Glacier Surface Ablation; Ice Velocity; Velocity Measurements; Taylor Glacier; Isotope; GPS; Ice Sheet Elevation; Not provided; FIELD INVESTIGATION; Ice Surface Elevation; Ablation; Oxygen Isotope; Elevation; Deuterium; GROUND-BASED OBSERVATIONS; Glacier Surface Ablation Rate; Surface Elevation", "locations": "Taylor Glacier", "north": -77.6, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "paleo_time": null, "persons": "Bliss, Andrew; Kavanaugh, Jeffrey; Aciego, Sarah; Cuffey, Kurt M.; Morse, David L.; Blankenship, Donald D.", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; Not provided; SPACE-BASED PLATFORMS \u003e NAVIGATION SATELLITES \u003e GLOBAL POSITIONING SYSTEM (GPS) \u003e GPS", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.9, "title": "Collaborative Research: Dynamics and Climatic Response of the Taylor Glacier System", "uid": "p0000084", "west": 160.0}, {"awards": "0126270 Doran, Peter", "bounds_geometry": null, "dataset_titles": null, "datasets": null, "date_created": "Mon, 05 Feb 2007 00:00:00 GMT", "description": "Polar Programs, provides funds for a study of sediment cores from the McMurdo Dry Valley lakes. The Dry Valley lakes have a long history of fluctuating levels reflecting regional climate change. The history of lake level fluctuations is generally known from the LGM to early Holocene through 14C dates of buried organic matter in paleolake deposits. However, the youngest paleolake deposits available are between 8000 to 9000 14C yr BP, suggesting that lake levels were at or below current levels for much of the Holocene. Thus, any information about the lake history and climate controls for the Holocene is largely contained in bottom sediments. This project will attempt to extract paleoclimatic information from sediment cores for a series of closed-basin dry valley lakes under study by the McMurdo LTER site. This work involves multiple approaches to dating the sediments and use of several climate proxy approaches to extract century to millennial scale chronologies from Antarctic lacustrine deposits. This research uses knowledge on lake processes gained over the past eight years by the LTER to calibrate climate proxies from lake sediments. Proxies for lake depth and ice thickness, which are largely controlled by summer climate, are the focus of this work. This study focuses on four key questions: 1. How sensitively do dry valley lake sediments record Holocene environmental and climate variability? 2. What is the paleoclimatic variability in the dry valleys on a century and millennial scale throughout the Holocene? Especially, is the 1200 yr evaporative event unique, or are there other such events in the record? 3. Does a mid-Holocene (7000 to 5000 yr BP) climate shift occur in the dry valleys as documented elsewhere in the polar regions? 4. Is there evidence, in the dry valley lake record of the 1500 yr Holocene periodicities recently recognized in the Taylor Dome record? Core collection will be performed with LTER support using a state-of-the-art percussion/piston corer system that has been used successfully to retrieve long cores (10 to 20 m) from other remote polar locations. Analyses to be done include algal pigments, biogenic silica, basic geochemistry, organic and inorganic carbon and nitrogen content, stable isotopes of carbon, nitrogen, and oxygen, carbonate phases, salt content and mineralogy, and grain size. In addition this project will pursue a multi-chronometer approach to assess the age of the core through optically-stimulated luminescence, 226Ra/230Th , 230Th/234U, and 14C techniques. New experimentation with U-series techniques will be performed to allow for greater precision in the dry valley lake sediments. Compound specific isotopes and lipid biomarkers , which are powerful tools for inferring past lake conditions, will also be assessed. Combined, these analyses will provide a new century to millennial scale continuous record of the Holocene climate change in the Ross Sea region.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e SEDIMENT CORERS", "is_usap_dc": false, "keywords": "Not provided", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e QUATERNARY", "persons": "Doran, Peter", "platforms": "Not provided", "repositories": null, "science_programs": null, "south": null, "title": "Paleoclimate Inferred from Lake Sediment Cores in Taylor Valley, Antarctica", "uid": "p0000092", "west": null}]

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