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Snowpack in Antarctica
Modelling of the Antarctic snow pack with SNOWPACK to study the mass and energy exchange processes. A bibliographic research compile the actual knowledge about snow modelling in Antarctica.
The surface snow cover of the Antarctic Plateau has distinct characteristics from the snow cover in the Alps. Low yearly accumulation, very low air and snow temperatures as well as the wind strongly influence the evolution of the snow cover. These factors also make numerical simulations of the Antarctic snow cover a challenge. Together with the Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto ARPAV, Italia, we study the surface snow and its interaction with the atmosphere.
The data were
collected near Dome C (Concordia Station) during various Italian
expeditions as well as from an Automatic Weather Station. Data include observations of
the depth of snowfall, detailed snow profiles of the surface snow, erosion and
deposition observations, snow temperatures as well as standard (continuing) meteorological
data such as air temperature and humidity, wind, and both short and longwave
We first performed a quality check of the data. The extreme conditions often lead to data losses that have to be filled by interpolation or by using data from other nearby stations. Our complete data set now covers approx. two consecutive years, namely 2006 and 2007.
data are used to drive the snow-cover model SNOWPACK that was developed
for Alpine regions. However, some of the parameterizations are based on datasets
of the Alpine regions and cannot be extrapolated to the Antarctic climate. For
instance snow settlement at temperatures below -20 °C and the
characteristics of new snow differ strongly. These parameterizations were
therefore adjusted. Moreover, a new method that was implemented in SNOWPACK is
the deposition of snow fall during so-called events, which we basically use to
simulate snow drifts. Model results showed that we can thereby accurately
describe the energy balance of the Antarctic snowpack. We also appear to obtain
a snow stratigraphy more similar to observations thanks to the deposition of
snow in events. However, especially the model validation considering snow
stratigraphy is difficult due to large spatial variability of the snow cover within
few meters. Current research therefore also focuses on describing this
variability and searching for common characteristics of snow profiles that
could help model validation.
Stazione Giulia, Antarctica. Photo by Mauro Valt.