Assessment of drought prone areas in Slovakia according to the changes in the long-term mean discharges

The assessment of changes in the hydrological regime under the climate change uncertainty is especially important for the decision making processes as the hydrological design values, derived for a reference period, are directly used for decision making in many areas of water management, including drought management. Recent local studies confirmed that there are changes in hydrological regime of the last decades in comparison to the currently used reference period 1961-2000 in Slovakia. Therefore, the selection of the reference period for the design values is under revision. In the first step, long-term mean discharge observations from the state hydrological network with near natural regime were analysed. The newly proposed period 1991-2020 was compared to the reference period 1961-2000 and the deviations of long-term discharges in selected water-gauging stations were assessed. The newly proposed reference period was selected for the analysis, as it is recommended by the World Meteorological Organisation for the purpose of climate change monitoring and better comparability of climatological and hydrological characteristics. As the second step, maps of the drought prone areas were drawn according to the spatial distribution of the results. We hope that this analysis will serve as supporting material to help the decision makers in policy making process and toward more effective drought management in Slovakia.