Tytuł pozycji:
Uwarunkowania klimatyczne aktywności geomorficznej, Wyspa Króla Jerzego, Szetlandy Południowe
The paper presents the proposal of a method for an indirect evaluation of geomorphic activity on ice-free areas on King George Island (South Shetlands, West Antarctica) through analysis of climatic conditions affecting the mobility of mineral matter. It was assumed that weather conditions affected the movement of mineral matter, which in turn determined geomorphic activity on ice-free areas, which currently occupy over 25 km2 of Admiralty Bay. On the basis of encoded values of six variables: air temperature, wind speed, rainfall, sunshine, ground temperature, and thickness of snow cover, diurnal types of the efficiency of mineral matter circulation were determined which were then clustered using the k-means method. After the cumulation of results for 7-day periods, a total of 59 homogeneous periods were obtained characterised by diurnal types of geomorphic activity (1, 2 and 3) in the observation period from April 10, 1990 to January 13, 1994. The summer season is a period with a high efficiency of mineral matter circulation and geomorphic activity, while winter time is one with a low efficiency of mineral matter circulation and geomorphic activity. Periods with an average efficiency of mineral matter circulation and geomorphic activity correspond to ascending and descending transition times. It is possible to associate the descending period with the autumn season in the temperate zone, while the ascending period, with spring-time.