Journal cover Journal topic
The Cryosphere An interactive open-access journal of the European Geosciences Union
The Cryosphere, 8, 1205-1215, 2014
© Author(s) 2014. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
14 Jul 2014
The growth of sublimation crystals and surface hoar on the Antarctic plateau
J.-C. Gallet1,2,3, F. Domine2,3,4, J. Savarino2,3, M. Dumont5, and E. Brun6 1Norwegian Polar Institute, Tromsø, Norway
2CNRS, LGGE, 38041 Grenoble, France
3Université Grenoble Alpes, LGGE, 38041 Grenoble, France
4Takuvik Joint International Laboratory and Department of Chemistry, Université Laval and CNRS, Quebec, Canada
5Météo-France-CNRS, CNRM-GAME UMR 3589, CEN, Saint-Martin d'Hères, France
6Météo-France-CNRS, CNRM-GAME UMR 3589, Toulouse, France
Abstract. On the Antarctic plateau, precipitation quantities are so low that the surface mass budget is for an important part determined by exchanges of water vapor between the snow surface and the atmosphere surface. At Dome C (75° S, 123° E), we have frequently observed the growth of crystals on the snow surface under calm sunny weather. Here we present the time variations of specific surface area (SSA) and density of these crystals. Using the detailed snow model Crocus, we conclude that the formation of these crystals was very likely due to the nighttime formation of surface hoar crystals and to the daytime formation of sublimation crystals. These latter crystals form by processes similar to those involved in the formation of frost flowers on young sea ice. The formation of these crystals impacts the albedo, mass and energy budget of the Antarctic plateau. In particular, the SSA variations of the surface layer can induce an instantaneous forcing at the snow surface up to −10 W m−2 at noon, resulting in a surface temperature drop of 0.45 K. This result confirms that snow SSA is a crucial variable to consider in the energy budget and climate of snow-covered surfaces.

Citation: Gallet, J.-C., Domine, F., Savarino, J., Dumont, M., and Brun, E.: The growth of sublimation crystals and surface hoar on the Antarctic plateau, The Cryosphere, 8, 1205-1215, doi:10.5194/tc-8-1205-2014, 2014.
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