WSL Institute for Snow and Avalanche Research SLF Link zu SLF Hauptseite Link zu WSL Hauptseite
 

Contact

Research Group

Related Projects

Publications

  • Groot Zwaaftink, C.D.; Cagnati, A.; Crepaz, A.; Fierz, C.; Macelloni, G.; Valt, M.; Lehning, M., 2013: Event-driven deposition of snow on the Antarctic Plateau: analyzing field measurements with SNOWPACK. Link
  • more ...

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 incoming radiation.

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.

These 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.
Future applications of the model might be for studies on snow chemistry and to gain insight in and to better quantify snow-atmosphere interaction processes.

Antarctica

Stazione Giulia, Antarctica. Photo by Mauro Valt.