{"dp_type": "Dataset", "free_text": "Delta 13C"}
[{"awards": "2031442 Learman, Deric", "bounds_geometry": null, "date_created": "Thu, 08 Sep 2022 00:00:00 GMT", "description": "Shelf sediment samples were collected around the Antarctic Peninsular with the mega corer in 2020 (Nov. to Dec.). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set (10). ", "east": null, "geometry": null, "keywords": "Antarctica; Antarctic Peninsula; Grain Size; Grain Size Analysis; Marine Geoscience; Marine Sediments; Organic Matter Geochemistry; Sediment Core Data; Shelf Sediments; Weddell Sea", "locations": "Antarctic Peninsula; Weddell Sea; Antarctica", "north": null, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Learman, Deric", "project_titles": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments", "projects": [{"proj_uid": "p0010235", "repository": "USAP-DC", "title": "RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Physical and geochemical data from shelf sediments near the Antartic Pennisula", "uid": "601607", "west": null}, {"awards": "0732625 Leventer, Amy; 1433140 Domack, Eugene", "bounds_geometry": ["POLYGON((-69 -58,-67.7 -58,-66.4 -58,-65.1 -58,-63.8 -58,-62.5 -58,-61.2 -58,-59.9 -58,-58.6 -58,-57.3 -58,-56 -58,-56 -59,-56 -60,-56 -61,-56 -62,-56 -63,-56 -64,-56 -65,-56 -66,-56 -67,-56 -68,-57.3 -68,-58.6 -68,-59.9 -68,-61.2 -68,-62.5 -68,-63.8 -68,-65.1 -68,-66.4 -68,-67.7 -68,-69 -68,-69 -67,-69 -66,-69 -65,-69 -64,-69 -63,-69 -62,-69 -61,-69 -60,-69 -59,-69 -58))"], "date_created": "Mon, 15 Nov 2021 00:00:00 GMT", "description": "This data set contains an age vs depth model and measurements of magnetic susceptibility, benthic foraminifera Bulimina aculeata d18O and d13C, bulk sediment GDGT data, and diatom assemblage data from USAP LMG13-11 JKC-1 sediment core (0-100 cm) archived at the Oregon State University ACC repository. All stable isotope and GDGT measurements were made at the University of South Florida College of Marine Science. Diatom assemblages were counted at Colgate University. The data set includes all replicate measurements. Details of the entire data set and all relevant methods are provided in Browne et al (submitted, 2021)", "east": -56.0, "geometry": ["POINT(-62.5 -63)"], "keywords": "Antarctica; Antarctic Peninsula; Delta 13C; Delta 18O; Paleoceanography; Temperature", "locations": "Antarctic Peninsula; Antarctica", "north": -58.0, "nsf_funding_programs": "Antarctic Integrated System Science; Antarctic Integrated System Science", "persons": "Shevenell, Amelia", "project_titles": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans", "projects": [{"proj_uid": "p0000101", "repository": "USAP-DC", "title": "Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "LARISSA", "south": -68.0, "title": "LMG13-11 JKC-1 Paleoceanographic data", "uid": "601485", "west": -69.0}, {"awards": "1443386 Emslie, Steven", "bounds_geometry": ["POLYGON((-58.62 -62.257,-58.6199 -62.257,-58.6198 -62.257,-58.6197 -62.257,-58.6196 -62.257,-58.6195 -62.257,-58.6194 -62.257,-58.6193 -62.257,-58.6192 -62.257,-58.6191 -62.257,-58.619 -62.257,-58.619 -62.2571,-58.619 -62.2572,-58.619 -62.2573,-58.619 -62.2574,-58.619 -62.2575,-58.619 -62.2576,-58.619 -62.2577,-58.619 -62.2578,-58.619 -62.2579,-58.619 -62.258,-58.6191 -62.258,-58.6192 -62.258,-58.6193 -62.258,-58.6194 -62.258,-58.6195 -62.258,-58.6196 -62.258,-58.6197 -62.258,-58.6198 -62.258,-58.6199 -62.258,-58.62 -62.258,-58.62 -62.2579,-58.62 -62.2578,-58.62 -62.2577,-58.62 -62.2576,-58.62 -62.2575,-58.62 -62.2574,-58.62 -62.2573,-58.62 -62.2572,-58.62 -62.2571,-58.62 -62.257))"], "date_created": "Sun, 11 Oct 2020 00:00:00 GMT", "description": "Many types of animal tissues are increasingly being used for stable isotope analysis, with their application dependent on the time frame they reflect and their availability for collection. Here, we investigated the isotopic values (\u03b413C and \u03b415N) of four tissues (feather, skin, toenail, and bone) collected from fledgling-period chick carcasses of three species of pygoscelid penguins to compare the variability and accuracy of the data among tissues. Samples were collected at 25 de Mayo/King George Island during the 2017/18 austral summer. Chick carcasses are commonly found at active penguin colonies, and \u201copportunistic sampling\u201d can easily be performed without disturbing nesting penguins. A total of 25\u201336 carcasses per species were sampled at active colonies of Ad\u00e9lie Pygoscelis adeliae, Gentoo P. papua, and Chinstrap P. antarcticus penguins. A linear mixed model showed that \u03b413C values varied significantly between tissues, presumably due to tissue-specific isotopic discrimination. In contrast, the only tissue with significantly different \u03b415N values was toenail. Stable isotope data revealed dietary differences among species, with Gentoo Penguins having higher average isotopic values in tissues compared to Ad\u00e9lie and Chinstrap penguins. In addition, Chinstrap Penguins showed a consistent, but not statistically significant, trend in having higher \u03b413C values compared to Ad\u00e9lie Penguins. Gentoo Penguins displayed the highest isotopic variability of any species for all tissues. Isotopic composition was most variable in skin in all three species making skin the least reliable tissue for isotope analysis, whereas isotopic values were least variable in toenails. Comparison of isotopic values between two bones (tibiotarsus and coracoid) showed no significant differences in isotopic values, indicating that when the same bone is not available for sampling from carcasses, sampling of any major skeletal element is likely to provide a meaningful comparison. These results allow for more informed opportunistic sampling to accurately estimate and compare penguin diet among species and between ancient and active colonies.", "east": -58.619, "geometry": ["POINT(-58.6195 -62.2575)"], "keywords": "25 De Mayo/King George Island; Antarctica; Biota; Delta 13C; Delta 15N; Dietary Shifts; Opportunistic Sampling; Penguin; Pygoscelis Penguins; Stranger Point", "locations": "Stranger Point; 25 De Mayo/King George Island; Antarctica", "north": -62.257, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Ciriani, Yanina; Emslie, Steven", "project_titles": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators", "projects": [{"proj_uid": "p0010047", "repository": "USAP-DC", "title": "Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -62.258, "title": "Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica", "uid": "601382", "west": -58.62}, {"awards": "1443482 Mak, 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))"], "date_created": "Thu, 09 Jul 2020 00:00:00 GMT", "description": "Data from measurement of CO mixing ratios and stable isotopes from the South Pole Ice Core for the first ca 10,000 years BP", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; CO; Delta 13C; Delta 18O; South Pole; SPICEcore", "locations": "South Pole; Antarctica", "north": -60.0, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Mak, John", "project_titles": "Collaborative Research: Using Stable Isotopes to Constrain the Atmospheric Carbon Monoxide Budget over the Last 20,000 Years", "projects": [{"proj_uid": "p0010117", "repository": "USAP-DC", "title": "Collaborative Research: Using Stable Isotopes to Constrain the Atmospheric Carbon Monoxide Budget over the Last 20,000 Years"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "SPICEcore", "south": -90.0, "title": "Carbon monoxide mixing ratios and stable isotopic values, SPICE", "uid": "601356", "west": -180.0}, {"awards": "1245821 Brook, Edward J.", "bounds_geometry": ["POINT(162.167 -77.733)"], "date_created": "Fri, 01 Jan 2016 00:00:00 GMT", "description": "This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, and delta 18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, delta 13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of delta 13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica.", "east": 162.167, "geometry": ["POINT(162.167 -77.733)"], "keywords": "Antarctica; Atmosphere; Geochemistry; Ice Core Records; Isotope; Paleoclimate; Taylor Glacier; Transantarctic Mountains", "locations": "Taylor Glacier; Transantarctic Mountains; Antarctica", "north": -77.733, "nsf_funding_programs": null, "persons": "Brook, Edward J.", "project_titles": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "projects": [{"proj_uid": "p0000283", "repository": "USAP-DC", "title": "Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.733, "title": "The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive", "uid": "600163", "west": 162.167}, {"awards": "9980691 Wahlen, Martin", "bounds_geometry": ["POINT(-148.82 -81.66)"], "date_created": "Thu, 11 Dec 2003 00:00:00 GMT", "description": "These data are CO2 concentrations of the air occulded in Siple Dome ice core, Antarctica. The study was conducted between January 2001 and March 2003 on a deep ice core from Siple Dome Core A, located at 81.66 S, 148.82 W.", "east": -148.82, "geometry": ["POINT(-148.82 -81.66)"], "keywords": "Antarctica; Chemistry:fluid; Chemistry:Fluid; CO2; Geochemistry; Glaciers/ice Sheet; Glaciers/Ice Sheet; Ice Core Records; Paleoclimate; Siple Dome; Siple Dome Ice Core", "locations": "Siple Dome; Antarctica", "north": -81.66, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Ahn, Jinho; Wahlen, Martin; Deck, Bruce", "project_titles": "CO2 and Delta 13CO2 in Antarctic Ice Cores", "projects": [{"proj_uid": "p0000166", "repository": "USAP-DC", "title": "CO2 and Delta 13CO2 in Antarctic Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.66, "title": "Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica", "uid": "609202", "west": -148.82}]
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Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
---|---|---|---|---|---|---|---|---|---|
Physical and geochemical data from shelf sediments near the Antartic Pennisula
|
2031442 |
2022-09-08 | Learman, Deric |
RAPID: Meta-genomic and Transcriptomic Investigation of Complex Organic Matter Degradation in Antarctic Benthic Sediments |
Shelf sediment samples were collected around the Antarctic Peninsular with the mega corer in 2020 (Nov. to Dec.). The sample locations and water depths are recorded in this dataset. These samples were used to collect data on organic matter (total organic carbon, total nitrogen, delta 13C (organic), delta 15N, and C to N ratios). Nutrient data (nitrate, nitrite, sulfate, and ammonia) and grain size analysis were collected on a subsample set (10). | [] | [] | false | false |
LMG13-11 JKC-1 Paleoceanographic data
|
0732625 1433140 |
2021-11-15 | Shevenell, Amelia |
Collaborative Research in IPY: Abrupt Environmental Change in the Larsen Ice Shelf System, a Multidisciplinary Approach -- Cryosphere and Oceans |
This data set contains an age vs depth model and measurements of magnetic susceptibility, benthic foraminifera Bulimina aculeata d18O and d13C, bulk sediment GDGT data, and diatom assemblage data from USAP LMG13-11 JKC-1 sediment core (0-100 cm) archived at the Oregon State University ACC repository. All stable isotope and GDGT measurements were made at the University of South Florida College of Marine Science. Diatom assemblages were counted at Colgate University. The data set includes all replicate measurements. Details of the entire data set and all relevant methods are provided in Browne et al (submitted, 2021) | ["POLYGON((-69 -58,-67.7 -58,-66.4 -58,-65.1 -58,-63.8 -58,-62.5 -58,-61.2 -58,-59.9 -58,-58.6 -58,-57.3 -58,-56 -58,-56 -59,-56 -60,-56 -61,-56 -62,-56 -63,-56 -64,-56 -65,-56 -66,-56 -67,-56 -68,-57.3 -68,-58.6 -68,-59.9 -68,-61.2 -68,-62.5 -68,-63.8 -68,-65.1 -68,-66.4 -68,-67.7 -68,-69 -68,-69 -67,-69 -66,-69 -65,-69 -64,-69 -63,-69 -62,-69 -61,-69 -60,-69 -59,-69 -58))"] | ["POINT(-62.5 -63)"] | false | false |
Stable isotope analysis of multiple tissues from chick carcasses of three pygoscelid penguins in Antarctica
|
1443386 |
2020-10-11 | Ciriani, Yanina; Emslie, Steven |
Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators |
Many types of animal tissues are increasingly being used for stable isotope analysis, with their application dependent on the time frame they reflect and their availability for collection. Here, we investigated the isotopic values (δ13C and δ15N) of four tissues (feather, skin, toenail, and bone) collected from fledgling-period chick carcasses of three species of pygoscelid penguins to compare the variability and accuracy of the data among tissues. Samples were collected at 25 de Mayo/King George Island during the 2017/18 austral summer. Chick carcasses are commonly found at active penguin colonies, and “opportunistic sampling” can easily be performed without disturbing nesting penguins. A total of 25–36 carcasses per species were sampled at active colonies of Adélie Pygoscelis adeliae, Gentoo P. papua, and Chinstrap P. antarcticus penguins. A linear mixed model showed that δ13C values varied significantly between tissues, presumably due to tissue-specific isotopic discrimination. In contrast, the only tissue with significantly different δ15N values was toenail. Stable isotope data revealed dietary differences among species, with Gentoo Penguins having higher average isotopic values in tissues compared to Adélie and Chinstrap penguins. In addition, Chinstrap Penguins showed a consistent, but not statistically significant, trend in having higher δ13C values compared to Adélie Penguins. Gentoo Penguins displayed the highest isotopic variability of any species for all tissues. Isotopic composition was most variable in skin in all three species making skin the least reliable tissue for isotope analysis, whereas isotopic values were least variable in toenails. Comparison of isotopic values between two bones (tibiotarsus and coracoid) showed no significant differences in isotopic values, indicating that when the same bone is not available for sampling from carcasses, sampling of any major skeletal element is likely to provide a meaningful comparison. These results allow for more informed opportunistic sampling to accurately estimate and compare penguin diet among species and between ancient and active colonies. | ["POLYGON((-58.62 -62.257,-58.6199 -62.257,-58.6198 -62.257,-58.6197 -62.257,-58.6196 -62.257,-58.6195 -62.257,-58.6194 -62.257,-58.6193 -62.257,-58.6192 -62.257,-58.6191 -62.257,-58.619 -62.257,-58.619 -62.2571,-58.619 -62.2572,-58.619 -62.2573,-58.619 -62.2574,-58.619 -62.2575,-58.619 -62.2576,-58.619 -62.2577,-58.619 -62.2578,-58.619 -62.2579,-58.619 -62.258,-58.6191 -62.258,-58.6192 -62.258,-58.6193 -62.258,-58.6194 -62.258,-58.6195 -62.258,-58.6196 -62.258,-58.6197 -62.258,-58.6198 -62.258,-58.6199 -62.258,-58.62 -62.258,-58.62 -62.2579,-58.62 -62.2578,-58.62 -62.2577,-58.62 -62.2576,-58.62 -62.2575,-58.62 -62.2574,-58.62 -62.2573,-58.62 -62.2572,-58.62 -62.2571,-58.62 -62.257))"] | ["POINT(-58.6195 -62.2575)"] | false | false |
Carbon monoxide mixing ratios and stable isotopic values, SPICE
|
1443482 |
2020-07-09 | Mak, John |
Collaborative Research: Using Stable Isotopes to Constrain the Atmospheric Carbon Monoxide Budget over the Last 20,000 Years |
Data from measurement of CO mixing ratios and stable isotopes from the South Pole Ice Core for the first ca 10,000 years BP | ["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))"] | ["POINT(0 -89.999)"] | false | false |
The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive
|
1245821 |
2016-01-01 | Brook, Edward J. |
Collaborative Research: The Taylor Glacier, Antarctica, Horizontal Ice Core: Exploring changes in the Natural Methane Budget in a Warming World and Expanding the Paleo-archive |
This award supports a project to use the Taylor Glacier, Antarctica, ablation zone to collect ice samples for a range of paleoenvironmental studies. A record of carbon-14 of atmospheric methane (14CH4) will be obtained for the last deglaciation and the Early Holocene, together with a supporting record of CH4 stable isotopes. In-situ cosmogenic 14C content and partitioning of 14C between different species (14CH4, C-14 carbon monoxide (14CO) and C-14 carbon dioxide (14CO2)) will be determined with unprecedented precision in ice from the surface down to ~67 m. Further age-mapping of the ablating ice stratigraphy will take place using a combination of CH4, CO2, and delta 18O of oxygen gas and H2O stable isotopes. High precision, high-resolution records of CO2, delta 13C of CO2, nitrous oxide (N2O) and N2O isotopes will be obtained for the last deglaciation and intervals during the last glacial period. The potential of 14CO2 and Krypton-81 (81Kr) as absolute dating tools for glacial ice will be investigated. The intellectual merit of proposed work includes the fact that the response of natural methane sources to continuing global warming is uncertain, and available evidence is insufficient to rule out the possibility of catastrophic releases from large 14C-depleted reservoirs such as CH4 clathrates and permafrost. The proposed paleoatmospheric 14CH4 record will improve our understanding of the possible magnitude and timing of CH4 release from these reservoirs during a large climatic warming. A thorough understanding of in-situ cosmogenic 14C in glacial ice (production rates by different mechanisms and partitioning between species) is currently lacking. Such an understanding will likely enable the use of in-situ 14CO in ice at accumulation sites as a reliable, uncomplicated tracer of the past cosmic ray flux and possibly past solar activity, as well as the use of 14CO2 at both ice accumulation and ice ablation sites as an absolute dating tool. Significant gaps remain in our understanding of the natural carbon cycle, as well as in its responses to global climate change. The proposed high-resolution, high-precision records of delta 13C of CO2 would provide new information on carbon cycle changes both during times of rising CO2 in a warming climate and falling CO2 in a cooling climate. N2O is an important greenhouse gas that increased by ~30% during the last deglaciation. The causes of this increase are still largely uncertain, and the proposed high-precision record of N2O concentration and isotopes would provide further insights into N2O source changes in a warming world. The broader impacts of proposed work include an improvement in our understanding of the response of these greenhouse gas budgets to global warming and inform societally important model projections of future climate change. The continued age-mapping of Taylor Glacier ablation ice will add value to this high-quality, easily accessible archive of natural environmental variability. Establishing 14CO as a robust new tracer for past cosmic ray flux would inform paleoclimate studies and constitute a valuable contribution to the study of the societally important issue of climate change. The proposed work will contribute to the development of new laboratory and field analytical systems. The data from the study will be made available to the scientific community and the broad public through the NSIDC and NOAA Paleoclimatology data centers. 1 graduate student each will be trained at UR, OSU and SIO, and the work will contribute to the training of a postdoc at OSU. 3 UR undergraduates will be involved in fieldwork and research. The work will support a new, junior UR faculty member, Petrenko. All PIs have a strong history of and commitment to scientific outreach in the forms of media interviews, participation in filming of field projects, as well as speaking to schools and the public about their research, and will continue these activities as part of the proposed work. This award has field work in Antarctica. | ["POINT(162.167 -77.733)"] | ["POINT(162.167 -77.733)"] | false | false |
Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica
|
9980691 |
2003-12-11 | Ahn, Jinho; Wahlen, Martin; Deck, Bruce |
CO2 and Delta 13CO2 in Antarctic Ice Cores |
These data are CO2 concentrations of the air occulded in Siple Dome ice core, Antarctica. The study was conducted between January 2001 and March 2003 on a deep ice core from Siple Dome Core A, located at 81.66 S, 148.82 W. | ["POINT(-148.82 -81.66)"] | ["POINT(-148.82 -81.66)"] | false | false |