Refreezing on the Greenland ice sheet: a comparison of parameterizations
Retention and refreezing of meltwater are acknowledged to be important processes for the mass budget of polar glaciers and ice sheets. Several parameterizations of these processes exist for use in energy and mass balance models. Due to a lack of direct observations, validation of these parameterizat...
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ftcopernicus:oai:publications.copernicus.org:tc12685 2023-05-15T16:28:13+02:00 Refreezing on the Greenland ice sheet: a comparison of parameterizations Reijmer, C. H. Broeke, M. R. Fettweis, X. Ettema, J. Stap, L. B. 2018-09-27 application/pdf https://doi.org/10.5194/tc-6-743-2012 https://tc.copernicus.org/articles/6/743/2012/ eng eng doi:10.5194/tc-6-743-2012 https://tc.copernicus.org/articles/6/743/2012/ eISSN: 1994-0424 Text 2018 ftcopernicus https://doi.org/10.5194/tc-6-743-2012 2020-07-20T16:25:46Z Retention and refreezing of meltwater are acknowledged to be important processes for the mass budget of polar glaciers and ice sheets. Several parameterizations of these processes exist for use in energy and mass balance models. Due to a lack of direct observations, validation of these parameterizations is difficult. In this study we compare a set of 6 refreezing parameterizations against output of two Regional Climate Models (RCMs) coupled to an energy balance snow model, the Regional Atmospheric Climate Model (RACMO2) and the Modèle Atmosphérique Régional (MAR), applied to the Greenland ice sheet. In both RCMs, refreezing is explicitly calculated in a snow model that calculates vertical profiles of temperature, density and liquid water content. Between RACMO2 and MAR, the ice sheet-integrated amount of refreezing differs by only 4.9 mm w.e yr −1 (4.5 %), and the temporal and spatial variability are very similar. For consistency, the parameterizations are forced with output (surface temperature, precipitation and melt) of the RCMs. For the ice sheet-integrated amount of refreezing and its inter-annual variations, all parameterizations give similar results, especially after some tuning. However, the spatial distributions differ significantly and the spatial correspondence between the RCMs is better than with any of the parameterizations. Results are especially sensitive to the choice of the depth of the thermally active layer, which determines the cold content of the snow in most parameterizations. These results are independent of which RCM is used to force the parameterizations. Text Greenland Ice Sheet Copernicus Publications: E-Journals Greenland The Cryosphere 6 4 743 762 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
Retention and refreezing of meltwater are acknowledged to be important processes for the mass budget of polar glaciers and ice sheets. Several parameterizations of these processes exist for use in energy and mass balance models. Due to a lack of direct observations, validation of these parameterizations is difficult. In this study we compare a set of 6 refreezing parameterizations against output of two Regional Climate Models (RCMs) coupled to an energy balance snow model, the Regional Atmospheric Climate Model (RACMO2) and the Modèle Atmosphérique Régional (MAR), applied to the Greenland ice sheet. In both RCMs, refreezing is explicitly calculated in a snow model that calculates vertical profiles of temperature, density and liquid water content. Between RACMO2 and MAR, the ice sheet-integrated amount of refreezing differs by only 4.9 mm w.e yr −1 (4.5 %), and the temporal and spatial variability are very similar. For consistency, the parameterizations are forced with output (surface temperature, precipitation and melt) of the RCMs. For the ice sheet-integrated amount of refreezing and its inter-annual variations, all parameterizations give similar results, especially after some tuning. However, the spatial distributions differ significantly and the spatial correspondence between the RCMs is better than with any of the parameterizations. Results are especially sensitive to the choice of the depth of the thermally active layer, which determines the cold content of the snow in most parameterizations. These results are independent of which RCM is used to force the parameterizations. |
format |
Text |
author |
Reijmer, C. H. Broeke, M. R. Fettweis, X. Ettema, J. Stap, L. B. |
spellingShingle |
Reijmer, C. H. Broeke, M. R. Fettweis, X. Ettema, J. Stap, L. B. Refreezing on the Greenland ice sheet: a comparison of parameterizations |
author_facet |
Reijmer, C. H. Broeke, M. R. Fettweis, X. Ettema, J. Stap, L. B. |
author_sort |
Reijmer, C. H. |
title |
Refreezing on the Greenland ice sheet: a comparison of parameterizations |
title_short |
Refreezing on the Greenland ice sheet: a comparison of parameterizations |
title_full |
Refreezing on the Greenland ice sheet: a comparison of parameterizations |
title_fullStr |
Refreezing on the Greenland ice sheet: a comparison of parameterizations |
title_full_unstemmed |
Refreezing on the Greenland ice sheet: a comparison of parameterizations |
title_sort |
refreezing on the greenland ice sheet: a comparison of parameterizations |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-6-743-2012 https://tc.copernicus.org/articles/6/743/2012/ |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-6-743-2012 https://tc.copernicus.org/articles/6/743/2012/ |
op_doi |
https://doi.org/10.5194/tc-6-743-2012 |
container_title |
The Cryosphere |
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6 |
container_issue |
4 |
container_start_page |
743 |
op_container_end_page |
762 |
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1766017851088437248 |