Control of the temperature signal in Antarctic proxies by snowfall dynamics
<p>Antarctica, the coldest and driest continent, is home to the largest ice sheet, whose mass is predominantly recharged by snowfall. A common feature of polar regions is the warming associated with snowfall, as moist oceanic air and cloud cover increase the surface temperature. Consequently,...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2023-12-01
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| Series: | The Cryosphere |
| Online Access: | https://tc.copernicus.org/articles/17/5373/2023/tc-17-5373-2023.pdf |
| _version_ | 1797387465535782912 |
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| author | A. P. M. Servettaz C. Agosta C. Kittel C. Kittel A. J. Orsi |
| author_facet | A. P. M. Servettaz C. Agosta C. Kittel C. Kittel A. J. Orsi |
| author_sort | A. P. M. Servettaz |
| collection | DOAJ |
| description | <p>Antarctica, the coldest and driest continent, is home to the largest ice sheet, whose mass is predominantly recharged by snowfall. A common feature of polar regions is the warming associated with snowfall, as moist oceanic air and cloud cover increase the surface temperature. Consequently, snow that accumulates on the ice sheet is deposited under unusually warm conditions. Here we use a polar-oriented regional atmospheric model to study the statistical difference between average and snowfall-weighted temperatures. During snowfall, the warm anomaly scales with snowfall amount, with the strongest sensitivity occurring at low-accumulation sites. Heavier snowfall in winter helps to decrease the annual snowfall-weighted temperature, but this effect is overwritten by the event-scale warming associated with precipitating atmospheric systems, which particularly contrast with the extremely cold conditions that occur in winter. Consequently, the seasonal range of snowfall-weighted temperature is reduced by 20 %. On the other hand, the annual snowfall-weighted temperature shows 80 % more interannual variability than the annual temperature due to the irregularity of snowfall occurrence and its associated temperature anomaly. Disturbances of the apparent annual temperature cycle and interannual variability have important consequences for the interpretation of water isotopes in precipitation, which are deposited with snowfall and commonly used for paleotemperature reconstructions from ice cores.</p> |
| first_indexed | 2024-03-08T22:24:32Z |
| format | Article |
| id | doaj.art-7f1b9e3b16024ec5a011de6b24d51c27 |
| institution | Directory Open Access Journal |
| issn | 1994-0416 1994-0424 |
| language | English |
| last_indexed | 2024-03-08T22:24:32Z |
| publishDate | 2023-12-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | The Cryosphere |
| spelling | doaj.art-7f1b9e3b16024ec5a011de6b24d51c272023-12-18T10:49:11ZengCopernicus PublicationsThe Cryosphere1994-04161994-04242023-12-01175373538910.5194/tc-17-5373-2023Control of the temperature signal in Antarctic proxies by snowfall dynamicsA. P. M. Servettaz0C. Agosta1C. Kittel2C. Kittel3A. J. Orsi4Biogeochemistry Research Center, Japan Agency for Marine-Earth Science and Technology, Yokosuka, 237-0061, JapanLaboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, 91190, FranceDepartment of Geography, UR SPHERES, University of Liège, Liège, BelgiumInstitut des Géosciences de l'Environnement, University Grenoble Alpes/CNRS/IRD/G-INP, Grenoble, 38000, FranceDepartment of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, V6T 1Z4, British Columbia, Canada<p>Antarctica, the coldest and driest continent, is home to the largest ice sheet, whose mass is predominantly recharged by snowfall. A common feature of polar regions is the warming associated with snowfall, as moist oceanic air and cloud cover increase the surface temperature. Consequently, snow that accumulates on the ice sheet is deposited under unusually warm conditions. Here we use a polar-oriented regional atmospheric model to study the statistical difference between average and snowfall-weighted temperatures. During snowfall, the warm anomaly scales with snowfall amount, with the strongest sensitivity occurring at low-accumulation sites. Heavier snowfall in winter helps to decrease the annual snowfall-weighted temperature, but this effect is overwritten by the event-scale warming associated with precipitating atmospheric systems, which particularly contrast with the extremely cold conditions that occur in winter. Consequently, the seasonal range of snowfall-weighted temperature is reduced by 20 %. On the other hand, the annual snowfall-weighted temperature shows 80 % more interannual variability than the annual temperature due to the irregularity of snowfall occurrence and its associated temperature anomaly. Disturbances of the apparent annual temperature cycle and interannual variability have important consequences for the interpretation of water isotopes in precipitation, which are deposited with snowfall and commonly used for paleotemperature reconstructions from ice cores.</p>https://tc.copernicus.org/articles/17/5373/2023/tc-17-5373-2023.pdf |
| spellingShingle | A. P. M. Servettaz C. Agosta C. Kittel C. Kittel A. J. Orsi Control of the temperature signal in Antarctic proxies by snowfall dynamics The Cryosphere |
| title | Control of the temperature signal in Antarctic proxies by snowfall dynamics |
| title_full | Control of the temperature signal in Antarctic proxies by snowfall dynamics |
| title_fullStr | Control of the temperature signal in Antarctic proxies by snowfall dynamics |
| title_full_unstemmed | Control of the temperature signal in Antarctic proxies by snowfall dynamics |
| title_short | Control of the temperature signal in Antarctic proxies by snowfall dynamics |
| title_sort | control of the temperature signal in antarctic proxies by snowfall dynamics |
| url | https://tc.copernicus.org/articles/17/5373/2023/tc-17-5373-2023.pdf |
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