{"dp_type": "Project", "free_text": "Snow Pits"}
[{"awards": "1745116 Scambos, Ted", "bounds_geometry": "POLYGON((-75 -69,-74 -69,-73 -69,-72 -69,-71 -69,-70 -69,-69 -69,-68 -69,-67 -69,-66 -69,-65 -69,-65 -69.5,-65 -70,-65 -70.5,-65 -71,-65 -71.5,-65 -72,-65 -72.5,-65 -73,-65 -73.5,-65 -74,-66 -74,-67 -74,-68 -74,-69 -74,-70 -74,-71 -74,-72 -74,-73 -74,-74 -74,-75 -74,-75 -73.5,-75 -73,-75 -72.5,-75 -72,-75 -71.5,-75 -71,-75 -70.5,-75 -70,-75 -69.5,-75 -69))", "dataset_titles": "Density, hydrology and geophysical measurements from the Wilkins Ice Shelf firn aquifer", "datasets": [{"dataset_uid": "601390", "doi": "10.15784/601390", "keywords": "Airborne Radar; Antarctica; Antarctic Peninsula; Firn; Firn Aquifer; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Hydrology; Snow/ice; Snow/Ice; Wilkins Ice Shelf", "people": "Mi\u00e8ge, Cl\u00e9ment; Koenig, Lora; Forster, Richard; Solomon, Kip; Miller, Olivia; Wallin, Bruce; Scambos, Ted; Miller, Julie; Montgomery, Lynn", "repository": "USAP-DC", "science_program": null, "title": "Density, hydrology and geophysical measurements from the Wilkins Ice Shelf firn aquifer", "url": "https://www.usap-dc.org/view/dataset/601390"}], "date_created": "Tue, 08 Sep 2020 00:00:00 GMT", "description": "Snow or firn aquifers are areas of subsurface meltwater storage that form in glaciated regions experiencing intense summer surface melting and high snowfall. Aquifers can induce hydrofracturing, and thereby accelerate flow or trigger ice-shelf instability leading to increased ice-sheet mass loss. Widespread aquifers have recently been discovered in Greenland. These have been modelled and mapped using new satellite and airborne remote-sensing techniques. In Antarctica, a series of catastrophic break-ups at the Wilkins Ice Shelf on the Antarctic Peninsula that was previously attributed to effects of surface melting and brine infiltration is now recognized as being consistent with a firn aquifer--possibly stimulated by long-period ocean swell--that enhanced ice-shelf hydrofracture. This project will verify inferences (from the same mapping approach used in Greenland) that such aquifers are indeed present in Antarctica. The team will survey two high-probability sites: the Wilkins Ice Shelf, and the southern George VI Ice Shelf. \u003cbr/\u003e\u003cbr/\u003eThis two-year study will characterize the firn at the two field sites, drill shallow (~60 m maximum) ice cores, examine snow pits (~2 m), and install two AMIGOS (Automated Met-Ice-Geophysics Observing System) stations that include weather, GPS, and firn temperature sensors that will collect and transmit measurements for at least a year before retrieval. Ground-penetrating radar survey in areas surrounding the field sites will track aquifer extent and depth variations. Ice and microwave model studies will be combined with the field-observed properties to further explore the range of firn aquifers and related upper-snow-layer conditions. This study will provide valuable experience for three early-career scientists. An outreach effort through field blogging, social media posts, K-12 presentations, and public lectures is planned to engage the public in the team\u0027s Antarctic scientific exploration and discovery.\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": -65.0, "geometry": "POINT(-70 -71.5)", "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e GPR", "is_usap_dc": true, "keywords": "USAP-DC; Firn Aquifer; USA/NSF; FIELD INVESTIGATION; AMD; GLACIERS/ICE SHEETS; Wilkens Ice Shelf; Antarctic Peninsula; Amd/Us", "locations": "Antarctic Peninsula; Wilkens Ice Shelf", "north": -69.0, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Scambos, Ted", "platforms": "LAND-BASED PLATFORMS \u003e FIELD SITES \u003e FIELD INVESTIGATION", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -74.0, "title": "Antarctic Firn Aquifers: Extent, Characteristics, and Comparison with Greenland Occurrences", "uid": "p0010126", "west": -75.0}, {"awards": "1341360 Steig, Eric", "bounds_geometry": "POINT(106 -77.5)", "dataset_titles": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "datasets": [{"dataset_uid": "601031", "doi": "10.15784/601031", "keywords": "Antarctica; Chemistry:ice; Chemistry:Ice; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Isotope; Lake Vostok; Snow Pit; WAIS Divide Ice Core", "people": "Schoenemann, Spruce; Steig, Eric J.", "repository": "USAP-DC", "science_program": "WAIS Divide Ice Core", "title": "Seasonal 17O Isotope Data from Lake Vostok and WAIS Divide Snow Pits", "url": "https://www.usap-dc.org/view/dataset/601031"}], "date_created": "Tue, 06 Jun 2017 00:00:00 GMT", "description": "Steig/1341360\u003cbr/\u003e\u003cbr/\u003eThis award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher.", "east": 106.0, "geometry": "POINT(106 -77.5)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -77.5, "nsf_funding_programs": "Antarctic Instrumentation and Support; Antarctic Glaciology", "paleo_time": null, "persons": "Steig, Eric J.", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -77.5, "title": "Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores", "uid": "p0000316", "west": 106.0}, {"awards": "0538494 Meese, Debra", "bounds_geometry": null, "dataset_titles": "Microstructural Location and Composition of Impurities in Polar Ice Cores", "datasets": [{"dataset_uid": "609436", "doi": "10.7265/N5DF6P5P", "keywords": "Antarctica; Arctic; Byrd Glacier; Byrd Ice Core; Chemistry:ice; Chemistry:Ice; Geochemistry; GISP2; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Lake Vostok; Paleoclimate; Vostok Ice Core", "people": "Baker, Ian; Obbard, Rachel", "repository": "USAP-DC", "science_program": null, "title": "Microstructural Location and Composition of Impurities in Polar Ice Cores", "url": "https://www.usap-dc.org/view/dataset/609436"}], "date_created": "Thu, 03 Jun 2010 00:00:00 GMT", "description": "0538494\u003cbr/\u003eMeese\u003cbr/\u003eThis award supports a project for physical properties research on snow pits and firn/ice cores with specific objectives that include stratigraphic analysis including determination of accumulation rates, annual layers, depth hoar, ice and wind crusts and rates of grain growth with depth. Studies of firn densification rates and how these parameters relate to the meteorology and climatology over the last 200 years of snow accumulation in Antarctica will also be investigated. The project will also determine the seasonality of accumulation by co-registration of stratigraphy and chemistry and determination of chemical species at the grain boundaries, how these may change with depth/densification (and therefore temperature), precipitation, and may affect grain growth. Fabric analyses will be made, including variation with depth, location on undulations and if any variation exists with climate/chemistry. The large spatial coverage of the US ITASE program offers the opportunity to determine how these parameters are affected by a large range of temperature, precipitation and topographic effects. The intellectual merit of the project includes the fact that ITASE is the terrestrial equivalent of a polar research vessel that provides a unique, logistically efficient, multi-dimensional (x, y, z and time) view of the atmosphere, ice sheet and their histories. Physical properties measurements/ analyses are an integral part of understanding the dynamic processes to which the accumulated snow is subjected. Recent advancements in the field along with multiple core sites provide an excellent opportunity to gain a much broader understanding of the spatial, temporal and physical variables that impact firnification and the possible resultant impact on climatic interpretation. In terms of broader impacts, the data collected by US ITASE and its international ITASE partners is available to a broad scientific community. US ITASE has an extensive program of public outreach and provides significant opportunities for many students to experience multidisciplinary Antarctic research. A graduate student, a post-doctoral fellow and at least one undergraduate would be funded by this work. Dr. Meese is also a member of the New England Science Collaborative, an organization that educates the public on climate change based on recent scientific advancements.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e MICROSCOPES; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e SCANNING ELECTRON MICROSCOPES", "is_usap_dc": false, "keywords": "LABORATORY; Grain Growth; FIELD SURVEYS; Accumulation Rate; Firn Core; FIELD INVESTIGATION; Chemistry; Snow Pit; Depth Hoar; Firn Density; Ice Core; Not provided; Stratigraphic Analysis; Firn; US ITASE; Annual Layers", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Meese, Deb; MEESE, DEBRA", "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": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "The Physical Properties of the US ITASE Firn and Ice Cores from South Pole to Taylor Dome", "uid": "p0000289", "west": null}, {"awards": "9526566 Bindschadler, Robert", "bounds_geometry": null, "dataset_titles": "Decadal-Length Composite West Antarctic Air Temperature Records", "datasets": [{"dataset_uid": "609097", "doi": "10.7265/N55D8PS0", "keywords": "Antarctica; Atmosphere; Automated Weather Station; Meteorology; Temperature; West Antarctica", "people": "Stearns, Charles R.; Shuman, Christopher A.", "repository": "USAP-DC", "science_program": null, "title": "Decadal-Length Composite West Antarctic Air Temperature Records", "url": "https://www.usap-dc.org/view/dataset/609097"}], "date_created": "Tue, 28 Nov 2006 00:00:00 GMT", "description": "This award is for support for a research program involving the use of passive microwave data to validate key paleoclimate indicators used in glaciologic research. The specific contributions of this research are: 1) to define the timing and spatial extent of hoar complexes, which may serve as visible, annual stratigraphic markers in ice cores, through a combination of satellite passive microwave data and field observations; and 2) to monitor temperature trends at the site with calibrated passive microwave brightness temperatures and to correlate these trends to proxy temperatures provided by oxygen and hydrogen stable isotope ratio profiles from snow pits and/or ice cores. The work will take place at Siple Dome, Antarctica as part of the field activities associated with the ice core drilling program there.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e RECORDERS/LOGGERS \u003e AWS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e SMMR; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e SPECTROMETERS/RADIOMETERS \u003e IMAGING SPECTROMETERS/RADIOMETERS \u003e SSM/I", "is_usap_dc": true, "keywords": "West Antarctica; Near-Surface Air Temperatures; Surface Temperatures; Special Sensor Microwave/imager; Passive Microwave Brightness Temperatures; Scanning Multichannel Microwave Radiometer; SSM/I; SSMR; AWS Byrd Station; NIMBUS-7; Emissivity Modeling; Antarctica; West Antarctic Ice Sheet; Not provided; DMSP; AWS Siple; Automated Weather Station; AWS Lynn; AWS Lettau; AWS", "locations": "Antarctica; West Antarctica; West Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Bindschadler, Robert; Shuman, Christopher A.; Stearns, Charles R.", "platforms": "Not provided; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e DEFENSE METEOROLOGICAL SATELLITE PROGRAM (DMSP) \u003e DMSP; SPACE-BASED PLATFORMS \u003e EARTH OBSERVATION SATELLITES \u003e NIMBUS \u003e NIMBUS-7", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Passive Microwave Remote Sensing for Paleoclimate Indicators at Siple Dome, Antarctica", "uid": "p0000191", "west": null}, {"awards": "9615347 Conway, Howard", "bounds_geometry": null, "dataset_titles": "Roosevelt Island Bedrock and Surface Elevations; Roosevelt Island Ice Core Density and Beta Count Data", "datasets": [{"dataset_uid": "609140", "doi": "10.7265/N51J97NB", "keywords": "Antarctica; Elevation; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; GPR; Roosevelt Island; Solid Earth", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Bedrock and Surface Elevations", "url": "https://www.usap-dc.org/view/dataset/609140"}, {"dataset_uid": "609139", "doi": "10.7265/N55718ZW", "keywords": "Antarctica; Beta Count; Density; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; Roosevelt Island", "people": "Conway, Howard", "repository": "USAP-DC", "science_program": null, "title": "Roosevelt Island Ice Core Density and Beta Count Data", "url": "https://www.usap-dc.org/view/dataset/609139"}], "date_created": "Fri, 23 May 2003 00:00:00 GMT", "description": "This award is for two years of support to perform radar investigations across former shear margins at Roosevelt Island and Ice Stream C in order to measure changes in the configuration and continuity of internal layers and the bed. The broad goal of these investigations is to gain an understanding of ice stream flow and the timing and mechanisms of ice stream shutdown. A high-resolution short-pulse radar system will be used for detailed examination of the uppermost hundred meters of the firn and ice, and a monopulse sounding-radar system will be used to image the rest of the ice column (including internal layers) and the bed. Changes in the shape and continuity of layers will be used to interpret mechanisms and modes of ice stream flow including the possible migration of stagnation fronts and rates of shut-down. Variations in bed reflectivity will be used to deduce basal hydrology conditions across lineations. Accumulation rates deduced from snow pits and shallow cores will be used to estimate near-surface depth-age profiles. Improved understanding of ice stream history opens the possibility of linking changes in the West Antarctic ice sheet with the geologic evidence from Northern Victoria Land and the ocean record of the retreat of the grounding line in the Ross Sea.", "east": null, "geometry": null, "instruments": "EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e ALTIMETERS \u003e RADAR ALTIMETERS \u003e RA; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR; EARTH REMOTE SENSING INSTRUMENTS \u003e ACTIVE REMOTE SENSING \u003e PROFILERS/SOUNDERS \u003e RADAR SOUNDERS \u003e RADAR ECHO SOUNDERS; IN SITU/LABORATORY INSTRUMENTS \u003e CORERS \u003e CORING DEVICES", "is_usap_dc": true, "keywords": "Radioactive Decay; Radar Echo Sounder; Antarctica; Radar Altimetry; Densification; Bedrock Elevation; Ice Sheet Elevation; Satellite Radar Data; GROUND-BASED OBSERVATIONS; Radar; Ice Core; Snow Stratigraphy; Terrain Elevation; Antarctic Ice Sheet; Stable Isotopes; Ice Surface Elevation; Surface Elevation; Glaciology; Snow Densification; Ice Core Data; GROUND STATIONS; Not provided; Altimetry; Antarctic; Ice Core Stratigraphy; Ice Stratigraphy", "locations": "Antarctic; Antarctica; Antarctic Ice Sheet", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "paleo_time": null, "persons": "Conway, Howard", "platforms": "LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND-BASED OBSERVATIONS; LAND-BASED PLATFORMS \u003e PERMANENT LAND SITES \u003e GROUND STATIONS; Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Radar Investigations of Former Shear Margins: Roosevelt Island and Ice Stream C", "uid": "p0000164", "west": null}]
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Project Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Dataset Links and Repositories | Abstract | Bounds Geometry | Geometry | Selected | Visible | |||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Antarctic Firn Aquifers: Extent, Characteristics, and Comparison with Greenland Occurrences
|
1745116 |
2020-09-08 | Scambos, Ted |
|
Snow or firn aquifers are areas of subsurface meltwater storage that form in glaciated regions experiencing intense summer surface melting and high snowfall. Aquifers can induce hydrofracturing, and thereby accelerate flow or trigger ice-shelf instability leading to increased ice-sheet mass loss. Widespread aquifers have recently been discovered in Greenland. These have been modelled and mapped using new satellite and airborne remote-sensing techniques. In Antarctica, a series of catastrophic break-ups at the Wilkins Ice Shelf on the Antarctic Peninsula that was previously attributed to effects of surface melting and brine infiltration is now recognized as being consistent with a firn aquifer--possibly stimulated by long-period ocean swell--that enhanced ice-shelf hydrofracture. This project will verify inferences (from the same mapping approach used in Greenland) that such aquifers are indeed present in Antarctica. The team will survey two high-probability sites: the Wilkins Ice Shelf, and the southern George VI Ice Shelf. <br/><br/>This two-year study will characterize the firn at the two field sites, drill shallow (~60 m maximum) ice cores, examine snow pits (~2 m), and install two AMIGOS (Automated Met-Ice-Geophysics Observing System) stations that include weather, GPS, and firn temperature sensors that will collect and transmit measurements for at least a year before retrieval. Ground-penetrating radar survey in areas surrounding the field sites will track aquifer extent and depth variations. Ice and microwave model studies will be combined with the field-observed properties to further explore the range of firn aquifers and related upper-snow-layer conditions. This study will provide valuable experience for three early-career scientists. An outreach effort through field blogging, social media posts, K-12 presentations, and public lectures is planned to engage the public in the team's Antarctic scientific exploration and discovery.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. | POLYGON((-75 -69,-74 -69,-73 -69,-72 -69,-71 -69,-70 -69,-69 -69,-68 -69,-67 -69,-66 -69,-65 -69,-65 -69.5,-65 -70,-65 -70.5,-65 -71,-65 -71.5,-65 -72,-65 -72.5,-65 -73,-65 -73.5,-65 -74,-66 -74,-67 -74,-68 -74,-69 -74,-70 -74,-71 -74,-72 -74,-73 -74,-74 -74,-75 -74,-75 -73.5,-75 -73,-75 -72.5,-75 -72,-75 -71.5,-75 -71,-75 -70.5,-75 -70,-75 -69.5,-75 -69)) | POINT(-70 -71.5) | false | false | |||||
Development of a Laser Spectroscopy System for Analysis of 17Oexcess on Ice Cores
|
1341360 |
2017-06-06 | Steig, Eric J. |
|
Steig/1341360<br/><br/>This award supports a two-year project to develop a method for rapid and precise measurements of the difference in 18O/16O and 17O/16O isotope ratios in water, referred to as the 17O-excess. Measurement of 17O-excess is a recent innovation in geochemistry, complementing traditional measurements of the ratios of hydrogen (D/H) and oxygen (18O/16O). Conventional measurements of 17O/16O are limited in number because of the time-consuming and laborious nature of the analyses, which involves the conversion of water to oxygen via fluorination, followed by high-precision mass spectrometry. This project will use a novel cavity ring-down spectroscopy (CRDS) system developed by a joint effort of the University of Washington and Picarro, Inc. (Santa Clara, CA), along with the Centre for Ice and Climate (Neils Bohr Institute, Copenhagen). The primary intellectual merit of the research is the improvement of the CRDS method for measurements of 17Oexcess of discrete samples of water, to obtain precision and accuracy competitive with conventional methods using mass spectrometry. This will be achieved by quantification of the effects of water vapor concentration variability and instrument memory, precise calibration of the instrument against standard waters, and improvements to the spectroscopic analyses. The CRDS system will also be coupled to continuous-flow systems for ice core analysis, in collaboration with the University of Colorado, Boulder. The goal is to have an operational system available for ice core processing associated with the next major U.S.-led ice core project at South Pole, in 2015-2017. The broader impacts of the research include the ability to measure 17O-excess in ambient atmospheric water vapor, which can be used to improve understanding of convection, moisture transport, and condensation. The instrument development work proposed here is relevant to research supported by several NSF-GEO programs, including Hydrology, Climate and Large Scale Dynamics, Paleoclimate, Atmosphere Chemistry, and both the Arctic and Antarctic Programs. This proposal will support a postdoctoral researcher. | POINT(106 -77.5) | POINT(106 -77.5) | false | false | |||||
The Physical Properties of the US ITASE Firn and Ice Cores from South Pole to Taylor Dome
|
0538494 |
2010-06-03 | Meese, Deb; MEESE, DEBRA |
|
0538494<br/>Meese<br/>This award supports a project for physical properties research on snow pits and firn/ice cores with specific objectives that include stratigraphic analysis including determination of accumulation rates, annual layers, depth hoar, ice and wind crusts and rates of grain growth with depth. Studies of firn densification rates and how these parameters relate to the meteorology and climatology over the last 200 years of snow accumulation in Antarctica will also be investigated. The project will also determine the seasonality of accumulation by co-registration of stratigraphy and chemistry and determination of chemical species at the grain boundaries, how these may change with depth/densification (and therefore temperature), precipitation, and may affect grain growth. Fabric analyses will be made, including variation with depth, location on undulations and if any variation exists with climate/chemistry. The large spatial coverage of the US ITASE program offers the opportunity to determine how these parameters are affected by a large range of temperature, precipitation and topographic effects. The intellectual merit of the project includes the fact that ITASE is the terrestrial equivalent of a polar research vessel that provides a unique, logistically efficient, multi-dimensional (x, y, z and time) view of the atmosphere, ice sheet and their histories. Physical properties measurements/ analyses are an integral part of understanding the dynamic processes to which the accumulated snow is subjected. Recent advancements in the field along with multiple core sites provide an excellent opportunity to gain a much broader understanding of the spatial, temporal and physical variables that impact firnification and the possible resultant impact on climatic interpretation. In terms of broader impacts, the data collected by US ITASE and its international ITASE partners is available to a broad scientific community. US ITASE has an extensive program of public outreach and provides significant opportunities for many students to experience multidisciplinary Antarctic research. A graduate student, a post-doctoral fellow and at least one undergraduate would be funded by this work. Dr. Meese is also a member of the New England Science Collaborative, an organization that educates the public on climate change based on recent scientific advancements. | None | None | false | false | |||||
Passive Microwave Remote Sensing for Paleoclimate Indicators at Siple Dome, Antarctica
|
9526566 |
2006-11-28 | Bindschadler, Robert; Shuman, Christopher A.; Stearns, Charles R. |
|
This award is for support for a research program involving the use of passive microwave data to validate key paleoclimate indicators used in glaciologic research. The specific contributions of this research are: 1) to define the timing and spatial extent of hoar complexes, which may serve as visible, annual stratigraphic markers in ice cores, through a combination of satellite passive microwave data and field observations; and 2) to monitor temperature trends at the site with calibrated passive microwave brightness temperatures and to correlate these trends to proxy temperatures provided by oxygen and hydrogen stable isotope ratio profiles from snow pits and/or ice cores. The work will take place at Siple Dome, Antarctica as part of the field activities associated with the ice core drilling program there. | None | None | false | false | |||||
Radar Investigations of Former Shear Margins: Roosevelt Island and Ice Stream C
|
9615347 |
2003-05-23 | Conway, Howard |
|
This award is for two years of support to perform radar investigations across former shear margins at Roosevelt Island and Ice Stream C in order to measure changes in the configuration and continuity of internal layers and the bed. The broad goal of these investigations is to gain an understanding of ice stream flow and the timing and mechanisms of ice stream shutdown. A high-resolution short-pulse radar system will be used for detailed examination of the uppermost hundred meters of the firn and ice, and a monopulse sounding-radar system will be used to image the rest of the ice column (including internal layers) and the bed. Changes in the shape and continuity of layers will be used to interpret mechanisms and modes of ice stream flow including the possible migration of stagnation fronts and rates of shut-down. Variations in bed reflectivity will be used to deduce basal hydrology conditions across lineations. Accumulation rates deduced from snow pits and shallow cores will be used to estimate near-surface depth-age profiles. Improved understanding of ice stream history opens the possibility of linking changes in the West Antarctic ice sheet with the geologic evidence from Northern Victoria Land and the ocean record of the retreat of the grounding line in the Ross Sea. | None | None | false | false |