{"dp_type": "Dataset", "free_text": "cosmogenic nuclides"}
[{"awards": "1142162 Stone, John", "bounds_geometry": ["POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a reconnaissance geological and radar-sounding study of promising sites in West Antarctica for a future project to measure cosmogenic nuclides in subglacial bedrock. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain the highest possible surface detail. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public.", "east": -85.14, "geometry": ["POINT(-94.64 -81.755)"], "keywords": "Antarctica; Be-10; Chemistry:rock; Chemistry:Rock; Cosmogenic Dating; Glaciology; Nunataks; Sample/collection Description; Sample/Collection Description; Solid Earth; Whitmore Mountains", "locations": "Whitmore Mountains; Antarctica", "north": -81.07, "nsf_funding_programs": null, "persons": "Stone, John", "project_titles": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "projects": [{"proj_uid": "p0000335", "repository": "USAP-DC", "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -82.44, "title": "Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling", "uid": "600162", "west": -104.14}, {"awards": "1043485 Curtice, Josh", "bounds_geometry": ["POLYGON((163.4 -77.47989,163.9848 -77.47989,164.5696 -77.47989,165.1544 -77.47989,165.7392 -77.47989,166.324 -77.47989,166.9088 -77.47989,167.4936 -77.47989,168.0784 -77.47989,168.6632 -77.47989,169.248 -77.47989,169.248 -77.565701,169.248 -77.651512,169.248 -77.737323,169.248 -77.823134,169.248 -77.908945,169.248 -77.994756,169.248 -78.080567,169.248 -78.166378,169.248 -78.252189,169.248 -78.338,168.6632 -78.338,168.0784 -78.338,167.4936 -78.338,166.9088 -78.338,166.324 -78.338,165.7392 -78.338,165.1544 -78.338,164.5696 -78.338,163.9848 -78.338,163.4 -78.338,163.4 -78.252189,163.4 -78.166378,163.4 -78.080567,163.4 -77.994756,163.4 -77.908945,163.4 -77.823134,163.4 -77.737323,163.4 -77.651512,163.4 -77.565701,163.4 -77.47989))"], "date_created": "Thu, 01 Jan 2015 00:00:00 GMT", "description": "This award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.\n", "east": 169.248, "geometry": ["POINT(166.324 -77.908945)"], "keywords": "Antarctica; Cosmogenic Dating; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean; WAIS", "locations": "Ross Sea; WAIS; Antarctica; Southern Ocean", "north": -77.47989, "nsf_funding_programs": null, "persons": "Kurz, Mark D.; Curtice, Josh", "project_titles": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "projects": [{"proj_uid": "p0000194", "repository": "USAP-DC", "title": "Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.338, "title": "A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea", "uid": "600123", "west": 163.4}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling
|
1142162 |
2016-01-01 | Stone, John |
Glacial-interglacial History of West Antarctic Nunataks and Site Reconnaissance for Subglacial Bedrock Sampling |
This award supports a reconnaissance geological and radar-sounding study of promising sites in West Antarctica for a future project to measure cosmogenic nuclides in subglacial bedrock. Field work will take place in the Whitmore Mountains, close to the WAIS divide, and on the Nash and Pirrit Hills, downflow from the divide in the Weddell Sea drainage. At each site geological indicators of higher (and lower) ice levels in the past will be mapped and evidence of subglacial erosion or its absence will be documented. Elevation transects of both glacial erratics and adjacent bedrock samples will be collected to establish the timing of recent deglaciation at the sites and provide a complement to similar measurements on material from depth transects obtained by future subglacial drilling. At each site, bedrock ridges will be traced into the subsurface with closely-spaced ice-penetrating radar surveys, using a combination of instruments and frequencies to obtain the highest possible surface detail. Collectively the results will define prospective sites for subglacial sampling, and maximize the potential information to be obtained from such samples in future studies. The intellectual merit of this project is that measurements of cosmogenic nuclides in subglacial bedrock hold promise for resolving the questions of whether the West Antarctic ice sheet collapsed completely in the past, whether it is prone to repeated large deglaciations, and if so, what is their magnitude and frequency. Such studies will require careful choice of targets, to locate sites where bedrock geology is favorable, cosmogenic nuclide records are likely to have been protected from subglacial erosion, and the local ice-surface response is indicative of large-scale ice sheet behavior. The broader impacts of this work include helping to determine whether subglacial surfaces in West Antarctica were ever exposed to cosmic rays, which will provide unambiguous evidence for or against a smaller ice sheet in the past. This is an important step towards establishing whether the WAIS is vulnerable to collapse in future, and will ultimately help to address uncertainty in forecasting sea level change. The results will also provide ground truth for models of ice-sheet dynamics and long-term ice sheet evolution, and will help researchers use these models to identify paleoclimate conditions responsible for WAIS deglaciation. The education and training of students (both undergraduate and graduate students) will play an important role in the project, which will involve Antarctic fieldwork, technically challenging labwork, data collection and interpretation, and communication of the outcome to scientists and the general public. | ["POLYGON((-104.14 -81.07,-102.24 -81.07,-100.34 -81.07,-98.44 -81.07,-96.54 -81.07,-94.64 -81.07,-92.74 -81.07,-90.84 -81.07,-88.94 -81.07,-87.04 -81.07,-85.14 -81.07,-85.14 -81.207,-85.14 -81.344,-85.14 -81.481,-85.14 -81.618,-85.14 -81.755,-85.14 -81.892,-85.14 -82.029,-85.14 -82.166,-85.14 -82.303,-85.14 -82.44,-87.04 -82.44,-88.94 -82.44,-90.84 -82.44,-92.74 -82.44,-94.64 -82.44,-96.54 -82.44,-98.44 -82.44,-100.34 -82.44,-102.24 -82.44,-104.14 -82.44,-104.14 -82.303,-104.14 -82.166,-104.14 -82.029,-104.14 -81.892,-104.14 -81.755,-104.14 -81.618,-104.14 -81.481,-104.14 -81.344,-104.14 -81.207,-104.14 -81.07))"] | ["POINT(-94.64 -81.755)"] | false | false |
A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea
|
1043485 |
2015-01-01 | Kurz, Mark D.; Curtice, Josh |
Collaborative Research: A New Reconstruction of the Last West Antarctic Ice Sheet Deglaciation in the Ross Sea |
This award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation. | ["POLYGON((163.4 -77.47989,163.9848 -77.47989,164.5696 -77.47989,165.1544 -77.47989,165.7392 -77.47989,166.324 -77.47989,166.9088 -77.47989,167.4936 -77.47989,168.0784 -77.47989,168.6632 -77.47989,169.248 -77.47989,169.248 -77.565701,169.248 -77.651512,169.248 -77.737323,169.248 -77.823134,169.248 -77.908945,169.248 -77.994756,169.248 -78.080567,169.248 -78.166378,169.248 -78.252189,169.248 -78.338,168.6632 -78.338,168.0784 -78.338,167.4936 -78.338,166.9088 -78.338,166.324 -78.338,165.7392 -78.338,165.1544 -78.338,164.5696 -78.338,163.9848 -78.338,163.4 -78.338,163.4 -78.252189,163.4 -78.166378,163.4 -78.080567,163.4 -77.994756,163.4 -77.908945,163.4 -77.823134,163.4 -77.737323,163.4 -77.651512,163.4 -77.565701,163.4 -77.47989))"] | ["POINT(166.324 -77.908945)"] | false | false |