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Abstrakt

The near-surface ice thermal structure of the Waldemarbreen, a 2.5-square km glacier located at 78°N 12°E in Spitsbergen, Svalbard , is described here. Traditional glaciological mass balance measurements by stake readings and snow surveying have been conducted annually since 1996. The near-surface ice temperature was investigated with automatic borehole thermistors in the ablation and accumulation areas in 2007-2008. The mean annual surface ice temperatures (September-June) of the ablation area were determined to be -4.7°C at 1 m depth and -2.5°C at 9 m . For the accumulation area, they were -3.0°C at 2 m , and -2.3°C at 10 m depth between September and August. On the Waldemarbreen, at 10 m depth, the mean annual near-surface ice temperature was 4.0°C above the mean annual air temperature in the accumulation area. The Waldemarbreen may thus be classified as a polythermal type with cold ice which is below the pressure melting point and a temperate ice layer in the bottom sections of the glacier and with a temperate surface layer only during summer seasons. At a depth of 10 m , temperatures are of the order of -2°C to -3°C.
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Abstrakt

The climatic change on King George Island (KGI) in the South Shetland Islands, Antarctica, in the years of 1948–2011 are presented. In the reference period, a statistically significant increase in the air temperature (0.19 ° C/10 years, 1.2 ° C in the analysed period) occurred along with a decrease in atmospheric pressure (−0.36 hPa/10 years, 2.3 hPa). In winter time, the warming up is more than twice as large as in summer. This leads to decrease in the amplitude of the annual cycle of air temperature. On KGI, there is also a warming trend of daily maximum and daily minimum air temperature. The evidently faster increase in daily minimum results in a decrease of the diurnal temperature range. The largest changes of air pressure took place in the summertime (−0.58 hPa/10 years) and winter (−0.34 hPa/10 years). The Semiannual Oscillation pattern of air pressure was disturbed. Climate changes on KGI are correlated with changing surface temperatures of the ocean and the concentration of sea ice. The precipitation on KGI is characterised by substantial variability year to year. In the analysed period, no statistically significant trend in atmospheric precipitation can be observed. The climate change on KGI results in substantial and rapid changes in the environment, which poses a great threat to the local ecosystem.
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