Long-term variability of heat waves and cold spells in Central Europe

Title: Long-term variability of heat waves and cold spells in Central Europe Author: Mgr. Ondřej Lhotka Department: Department of Physical Geography and Geoecology, Faculty of Science, Charles University in Prague Supervisor: RNDr. Jan Kyselý, Ph.D., Institute of Atmospheric Physics, Czech Academy of Sciences Abstract: Heat waves and cold spells have serious impacts on natural environment and society. The main aims of this thesis are to examine past variability of Central European heat waves and cold spells, to assess severity of recent events in a long-term context, to evaluate simulation of heat waves in climate models, and to construct their scenarios for a possible future climate. Heat waves and cold spells were primarily investigated as spatial events, using gridded data sets. E-OBS gridded data was utilized to assess past variability of heat waves and cold spells and to evaluate regional climate model (RCM) simulations from the ENSEMBLES and EURO-CORDEX projects. An extremity index that captures joint effects of temperature, duration, and spatial extent of individual heat waves and cold spells was proposed and tested. The persistent 1994 heat wave was found to be the most extreme over Central Europe in the 1950−2012 period, and the summer of 2013 was unprecedented at several Central European stations..