| Summary: | Analyses of shallow cores obtained at the European Project for Ice Coring in Antarctica (EPICA) drilling site Kohnen station (758000 S, 008040 E; 2892ma.s.l.) on the plateau of Dronning Maud Land reveal the presence of conserved snow dunes in the firn. In situ observations during three dune formation events in the 2005/06 austral summer at Kohnen station show that these periods were characterized by a phase of 2 or 3 days with snowdrift prior to dune formation which only occurred during high wind speeds of >10ms–1 at 2m height caused by the influence of a low-pressure system. The dune surface coverage after a formation event varied between 5% and 15%, with a typical dune size of (4 2)m (8 3) m, a maximum height of 0.2 0.1m and a periodicity length of about 30 m. The mean density within a snow dune varied between 380 and 500 kgm–3, whereas the mean density at the surrounding surface was 330 5kgm–3. The firn cores covering a time-span of 22 2 years reveal that approximately three to eight events per year occurred, during which snow dunes had been formed and were preserved in the firn.
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