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| Titel |
Surface energy budget of the Larsen C Ice Shelf, and its relation to atmospheric circulation |
| VerfasserIn |
P. Kuipers Munneke, J. C. King, T. Gray, M. R. van den Broeke, C. H. Reijmer |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250060445
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| Zusammenfassung |
| Ponding of melt water has played a pivotal role in the breakup of ice shelves in the past
decades. In-situ observations are important to determine the relation between meltwater
production and the atmospheric circulation over the ice shelves. Data collected
by two automatic weather stations (AWS) on the Larsen C ice shelf, Antarctica,
between 22 January 2009 and 1 February 2011 are analyzed and used as input for a
model that computes the surface energy budget (SEB), including melt energy. The
two AWSs are separated by about 70 km in the north-south direction, and both the
near-surface meteorology and the SEB show similarities, although small differences
in all components (most notably the melt flux) can be seen. In winter, longwave
cooling of the surface is entirely compensated by a downward turbulent transport of
sensible heat. In summer, the positive net radiative flux is compensated by melt, and
quite frequently by upward turbulent diffusion of heat and moisture, leading to
sublimation and weak convection over the ice shelf. The month of November 2010 is
highlighted, when strong westerly flow over the Antarctic Peninsula led to a dry and
warm föhn wind over the ice shelf, resulting in warm and sunny conditions. Under
these conditions the increase in shortwave and sensible heat fluxes is larger than the
reduction of net longwave and latent heat fluxes, providing energy for significant melt. |
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