Geographia Polonica (2000) vol. 73, iss. 2

Synoptic - climatic structure of the extreme air thermal phenomena in Poland

Zbigniew Ustrnul

Geographia Polonica (2000) vol. 73, iss. 2, pp. 99-110 | Full text

The influence of atmospheric circulation upon extreme temperatures in Poland is being analysed. Maximum and minimum temperature values have been collected from 19 meteorological (synoptic) stations for the period 1951-1999. Simultaneously, a catalogue of circulation types after Osuchowska-Klein has also been used. An analysis of mean monthly and seasonal values is provided, as well as the conditional probability of selected temperature thresholds during the occurrence of particular types. Days with maximum temperatures over 25°C, minimum temperatures below -15°C and the absolute extremes for the selected stations have been investigated in detail. This confirmed a significant influence of atmospheric circu-lation upon the occurrence of extreme temperatures much larger than other local factors. The last part contains an analysis of the number of days with given thermal characteristics with respect to circulation indices.

Keywords: maximum and minimum temperature, extreme temperature values, atmos-pheric circulation, synoptic climatology

Zbigniew Ustrnul, Institute of Meteorology and Water Management P. Borowego 14, 30-215 Kraków, Poland