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Titel |
Three examples where the specific surface area of snow increased over time |
VerfasserIn |
F. Domine, A.-S. Taillandier, A. Cabanes, T. A. Douglas, M. Sturm |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1994-0416
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Digitales Dokument |
URL |
Erschienen |
In: The Cryosphere ; 3, no. 1 ; Nr. 3, no. 1 (2009-03-16), S.31-39 |
Datensatznummer |
250000783
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Publikation (Nr.) |
copernicus.org/tc-3-31-2009.pdf |
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Zusammenfassung |
Snow on the ground impacts climate through its high albedo and affects
atmospheric composition through its ability to adsorb chemical compounds. The
quantification of these effects requires the knowledge of the specific
surface area (SSA) of snow and its rate of change. All relevant studies
indicate that snow SSA decreases over time. Here, we report for the first
time three cases where the SSA of snow increased over time. These are (1) the
transformation of a melt-freeze crust into depth hoar, producing an increase
in SSA from 3.4 to 8.8 m2 kg−1. (2) The mobilization of surface
snow by wind, which reduced the size of snow crystals by sublimation and
fragmented them. This formed a surface snow layer with a SSA of
61 m2 kg−1 from layers whose SSAs were originally 42 and
50 m2 kg−1. (3) The sieving of blowing snow by a snow layer, which
allowed the smallest crystals to penetrate into open spaces in the snow,
leading to an SSA increase from 32 to 61 m2 kg−1. We discuss that
other mechanisms for SSA increase are possible. Overall, SSA increases are
probably not rare. They lead to enhanced uptake of chemical compounds and to
increases in snow albedo, and their inclusion in relevant chemical and
climate models deserves consideration. |
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