@misc{Wibig_Joanna_Heatwaves_2009, author={Wibig, Joanna and Podstawczyńska, Agnieszka and Rzepa, Marcin and Piotrowski, Piotr}, volume={82}, number={1}, copyright={Rights Reserved - Free Access}, address={Warszawa}, journal={Geographia Polonica}, howpublished={online}, year={2009}, publisher={IGiPZ PAN}, language={eng}, abstract={The daily minimum and maximum temperatures at seven Polish stations were used in an analysis of the occurrence of heatwaves in the years 1951-2006. Heatwaves were defined as days with temperatures exceeding selected thresholds (tmax ≥25°C, tmax ≥30°C, tmin ≥18°C). The mean length of a wave of very warm days lasts from 2-4 days, the longest no fewer than 23 days. Waves comprising hot days and nights are shorter. The frequencies of very warm and hot days and hot nights increased in the analyzed period, especially its second half (1979-2006). The occurrence of heatwaves characteristically links up with high-pressure systems over Central Europe, along with associated blocking episodes.}, type={Text}, title={Heatwaves in Poland – frequency, trends and relationships with atmospheric circulation}, URL={http://www.rcin.org.pl/igipz/Content/55499/PDF/WA51_74820_r2009-t82-no1_G-Polonica-Wibig2.pdf}, keywords={extreme temperature, Sen's slope, Lund classification, composite method, Poland}, }