Changes in the structure of days with precipitation in Southern Poland in 1971-2010

摘要

In Poland, no clear tendencies have been detected in multi-year trends in precipitation sums. However, the number of days with precipitation has increased significantly. Therefore, we analyzed changes in the structure of days with precipitation, i.e., trends in the percentage of days with different ranges of daily precipitation sums. The precipitation data were from 1971-2010, from four stations in Southern Poland representing agricultural areas (Stare Olesno, Glubczyce, Lapanow, and Tuchow). Statistically significant upward trends (1-9 days per 10 years) and low variability were found for the number of days with daily precipitation sums up to 5 mm, mainly in the cold half of the year, and downward trends were found for days with 20-30 mm of precipitation (1 day per 10 years), with high variability. Comparison with the results of previous studies shows that the increase in the number of days with precipitation is not linked to a significant increase in precipitation sums.