In order to recognise the variability of the snow avalanche danger in the Tatra Mountains, the danger levels on consecutive days with snow cover over the last nine decades were calculated. To accomplish this task, the longest series of meteorological data were used from the Tatras along with an empirical method for determining the regional avalanche danger on the basis of elementary meteorological data. The results point to the fact that over the last 25 years the number of days with a level 2 avalanche danger significantly decreased, whereas the number of days with level 1 increased. This should result in a decreasing trend in the incidence of small and medium-sized natural avalanches. In the structure of snow cover, the percentage of melt forms might increase. However, this should not correlate with a significant increase in wet-snow avalanches, because the number of days with wet snow also reduces. The contemporary changes in the snow conditions and avalanche danger in the subalpine belt of the Tatras have been primarily associated with an increase in the air temperature (shorter winters and less snow).
Bogdan Gądek, Faculty of Earth Sciences University of Silesia in Katowice Będzińska 60, 41-200 Sosnowiec: Poland
Mariusz Grabiec, Centre for Polar Studies University of Silesia in Katowice Będzińska 60, 41-200 Sosnowiec: Poland
Zofia Rączkowska [firstname.lastname@example.org], Institute of Geography and Spatial Organization Polish Academy of Sciences, 31-018 Krakow, Sw. Jana 22, Poland
Andrzej Maciata, Tatra Volunteer Rescue Service Piłsudskiego 63A, Zakopane: Poland