Extreme precipitation over the Crimean península

Based on daily precipitation data for 1951-2009 from 18 hydrometeorological stations all over the Crimean peninsula, a 58-year data series of extreme precipitation parameters (precipitation concentration, level of extreme precipitation and number of days with extreme precipitation) were calculated. Linear trends of calculated parameters are estimated in this paper. Manifestations of the Pacific decadal oscillation (PDO) of the extreme precipitation changes were analyzed. The precipitation concentration is found to increase in the Crimean Mountains region in the winter season, but in the summer season the precipitation concentration is characterized by uniform distribution. Linear trends of the winter and summer precipitation concentration during the last 58 years are predominantly negative over Crimea. The maximum values of precipitation level in the winter season are typical for the Crimean Mountains region. In the summer season, values of precipitation change insignificantly. The number of days with extreme precipitation exhibits decreasing trends in the winter season over the territory of Crimea. In the summer season, the number of days with extreme precipitation in south-eastern part of Crimea has increasing trends. The negative PDO phase in the winter season was found to accompany increased precipitation concentration (up to 11%) all over Crimea and by decreased concentration (up to 4%) in the summer season in central, southern, and eastern regions of Crimea. The number of extreme precipitation days in the winter season is up to 30% higher in the negative PDO phase over the whole territory of Crimea, while in the summer it is up to 60% lower in the south-eastern part of peninsula.