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| Format: | Dataset Open Access |
| Langue: | en |
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PANGAEA
2017
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| Sujets: | |
| Accès en ligne: | https://doi.org/10.1594/PANGAEA.882249 |
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| _version_ | 1867171002429997056 |
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| author | Parrenin, Frédéric Cavitte, Marie G P Blankenship, Donald D Chappellaz, Jérôme A Fischer, Hubertus Gagliardini, Olivier Masson-Delmotte, Valerie Passalacqua, Olivier Ritz, Catherine Roberts, Jason L Siegert, Martin J Young, Duncan A |
| author_facet | Parrenin, Frédéric Cavitte, Marie G P Blankenship, Donald D Chappellaz, Jérôme A Fischer, Hubertus Gagliardini, Olivier Masson-Delmotte, Valerie Passalacqua, Olivier Ritz, Catherine Roberts, Jason L Siegert, Martin J Young, Duncan A |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Ice sheets provide exceptional archives of past changes in polar climate, regional environment and global atmospheric composition. The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ~800,000 years. Obtaining an older paleoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we use internal isochrones, identified from airborne radar coupled to ice-flow modelling to estimate the age of basal ice along transects in the Dome C area. Three glaciological properties are inverted from isochrones: surface accumulation rate; geothermal flux; and the exponent of the Lliboutry velocity profile. We find that old ice (>1 Myr, 1 million years) likely exists in two regions: one ~40 km south-west of Dome C along the ice divide to Vostok, close to a secondary dome that we name "Little Dome C" (LDC); and a second region named "North Patch" (NP) located 10-30 km north-east of Dome C, in a region where the geothermal flux is apparently relatively low. Our work demonstrates the value of combining radar observations with ice flow modelling to accurately represent the true nature of ice flow, and the formation of ice-sheet architecture, in the centre of large ice sheets. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_882249 |
| institution | PANGAEA |
| language | en |
| publishDate | 2017 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Basal age, surface accumulation, basal melting, geothermal flux and Lliboutry exponent of the velocity profile in the Dome C area Parrenin, Frédéric Cavitte, Marie G P Blankenship, Donald D Chappellaz, Jérôme A Fischer, Hubertus Gagliardini, Olivier Masson-Delmotte, Valerie Passalacqua, Olivier Ritz, Catherine Roberts, Jason L Siegert, Martin J Young, Duncan A Accumulation rate, standard deviation; Accumulation rate in ice equivalent per year; AGE; Antarctica; Distance; DomeC_area; Factor; Ground heat, flux; Ground heat, flux, standard deviation; Height; Ice thickness; LATITUDE; LONGITUDE; Melt rate; Melt rate, standard deviation; MULT; Multiple investigations; Number of years; Standard deviation Ice sheets provide exceptional archives of past changes in polar climate, regional environment and global atmospheric composition. The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ~800,000 years. Obtaining an older paleoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we use internal isochrones, identified from airborne radar coupled to ice-flow modelling to estimate the age of basal ice along transects in the Dome C area. Three glaciological properties are inverted from isochrones: surface accumulation rate; geothermal flux; and the exponent of the Lliboutry velocity profile. We find that old ice (>1 Myr, 1 million years) likely exists in two regions: one ~40 km south-west of Dome C along the ice divide to Vostok, close to a secondary dome that we name "Little Dome C" (LDC); and a second region named "North Patch" (NP) located 10-30 km north-east of Dome C, in a region where the geothermal flux is apparently relatively low. Our work demonstrates the value of combining radar observations with ice flow modelling to accurately represent the true nature of ice flow, and the formation of ice-sheet architecture, in the centre of large ice sheets. |
| title | Basal age, surface accumulation, basal melting, geothermal flux and Lliboutry exponent of the velocity profile in the Dome C area |
| topic | Accumulation rate, standard deviation; Accumulation rate in ice equivalent per year; AGE; Antarctica; Distance; DomeC_area; Factor; Ground heat, flux; Ground heat, flux, standard deviation; Height; Ice thickness; LATITUDE; LONGITUDE; Melt rate; Melt rate, standard deviation; MULT; Multiple investigations; Number of years; Standard deviation |
| url | https://doi.org/10.1594/PANGAEA.882249 |