Winter 2017/18: Largest amount of snow for Sonnblick glaciers over the last 20 years
Kleinfleißkees and Goldbergkees got 25 % more snow than in an average winter. For determination of snow depth, 560 measurements with snow probes were carried out. Additionally eight snow pits were dug for density and temperature measurements of the snowpack. The mean snow depth for Goldbergkees is 460 cm and for Kleinfleißkees it is 390 cm. Referring to density and snow depth measurements, the winter mass balance of Goldbergkees is 2080 mm w.e. a-1, that's 22 % above average and for Kleinfleißkees it is 1760 mm w.e. a-1. That is 25 % more than in an average winter.
The summers are crucial for Austria's glaciers. The extremely warm April has compensated the above-average snow cover. For early June, the snow depths are even below the average. For long-term development of glaciers in Austria, the weather conditions in summer are more important than in winter. Occasional occurred cold surges in summer brings snow cover on glaciers. Because a fresh, very with snow cover reflects almost all solar radiation. This can protect a glacier up to a week before melting. However, a glacier without fresh snow cover is much darker, therefore absorbs a lot of solar radiation an can lose up to 10 cm of ice thickness in one day.
Digging a snow pit (photo: V. Alge).
Accumulated snow depth between October 2017 and end of April 2018 for Kleinfleißkees (left) and Goldbergkees (right).
Time series of winter mass balance Kleinfleißkees and Goldbergkees.
View at Pasterze from webcam location Freiwandeck. Comparison between an image form late April (left) and late May (right). End of April, at the glacier snout were 90 cm of snow measured. End of May, at the same position no snow remained.