Wpływ pokrywy śnieżnej na termikę i grubość warstwy czynnej zmarzliny w obszarze tundrowym rejonu Polskiej Stacji Polarnej (SW Spitsbergen)

This dissertation depicts the results of a research carried out from 02.09.2000 to 02.09.2001on the thermic and thickness of permafrost active layer in the area/region of Hornsund fiord on South Spitsbergen. The full collection of data gathered during the whole year of carrying outthe research allows to observe the freezing, melting and the dynamics of the process during that period of time. It was shown that there is a great connection between the temperature of the vertical profile of the active layer and the snow cover especially between thick snowdrifts behind terrain obstacles where the snow cover lies longer, even until the second decade of July. It was noticed that the defrosted ground there reaches 85 cm, whereas in the areas where the snow cover melts faster the depth of the defrosted ground reaches 140-145 cm. On the basis of the research it was shown that the influence of the snow cover on the development and thermal phenomena of the active layer is much greater than it was known before. The characteristic structure of major wind directions and the shape of area raised marine terrace, nearby the Polish Polar Station cause the formation of snowdrifts in the same places every year. It leads to a special differentiation of the freezing process of the ground. On the basis of the photographs and the teledetective data there was drawn a map of the snowdrifts arrangement for the area being under research. The thickness of the active layer under snowdrifts is smaller. Moreover, the presented results also suggest that the potential increase in snowfall, resulting in thicker layer of the snow cover , may cause changes in the development and special differentiation of the active layer in the area of longlasting permafrost.