Spatial relationships of heavy rains in the Czech Republic

Abstract. Study of heavy rain events and their spatial distribution are of great importance. Such events cause local flooding, accelerate soil erosion and cause damage on property. Data for this study were derived by Sokol and Bližňák (2009) from radar reflectivity and daily rain gauge measurements for the period of 2002–2008. We selected heavy rain events using spatial and intensity constrains. We studied relationships between heavy rains, altitude and terrain roughness. Heavy rain totals correlate with both altitude and terrain roughness globally over the Czech Republic. The correlation is also significant for extreme heavy rain totals. The correlation of heavy rain intensities with altitude was not proven. The highest rates of average intensities are located in the south-eastern parts of the Czech Republic. The spatial distribution of heavy rain frequencies strongly corresponds to the spatial distribution of heavy rain totals. The highest percentage of heavy rains in total precipitation is located in the north-west of the Czech Republic. The extreme heavy rains occupy higher altitudes.