ABSTRACT
The moderate climate of Poland, transitional between oceanic and continental, is influenced by air masses from all directions – maritime and continental, polar and tropical. Events which have the most negative effect on people and the environment in Poland belong to meteorological hazards (rapid air pressure changes, extreme thermal conditions, droughts) and hydrological hazards (floods). There occur also geological hazard, i.e. landslides, which are closely related to meteorological conditions and radiological hazard of radon which is related to properties of the rocks. The warm half of the year is the most exposed season for natural hazards in Poland. Some of the greatest meteorological threats in Poland include exceptionally heavy or low precipitation, strong winds, violent maritime storms, extreme temperatures. The frequency of occurrence of torrential rainfalls has considerably increased over recent decades. Consequently, increased numbers of local urban floods have been observed. Most severe floods, in terms of flood fatalities and material damage, have occurred in valleys of large rivers (Vistula, Oder) and their tributaries, and particularly in urban agglomerations and industrial areas protected by embankments. The spatial distribution of the occurrence of drought spells in Poland is unfavorable for the country’s agriculture, because a major part of Poland’s agricultural potential is concentrated in regions that are most threatened with the possibility of drought (latitudinal belt in the central Poland). Landslides commonly occur in connection with torrential or long-duration rains or snowmelt, particularly in mountainous areas (Carpathian Mts., Sudety Mts.). Intensified landsliding activity was recorded in the end of 20th and in the beginning of the 21st centuries. The areas most affected by the radiological hazard of radon are the Sudety Mountains and the Fore-Sudetic block (SW part of Poland).
