ИСТИНА

Till now several classifications were developed to present climate differentiation in regional and global scales. The classifications use various indicators of climate (e.g. air temperature, precipitation, circulation type, vegetation etc.). The general classifications describe quite well the global variability of climates based on thermal and humidity/precipitation regimes. However, they do not provide any characteristics of human bioclimate. The possible reason is that bioclimatic indices used previously in research have many limitations which caused that they can't be used in wide (regional and global) scales. The newly developed Universal Thermal Climate Index (UTCI) is valid in all climates around the world and can be applied to develop regional and global bioclimatic regionalization. The aim of the presented research is to define and analyse principal features of bioclimate in Europe and to validate which characteristic are the most valuable as bioclimatic indicators. The research is carried out on the background of the Köppen-Geiger climate classification. Several characteristics based on UTCI were examined and found to be valuable in bioclimatic regionalization of Europe: 1) mean values of UTCI in the hottest and the coldest months; 2) frequency of days with at least strong heat stress in summer season and strong cold stress in winter season; 3) lasting of periods when risk of strong heat stress and strong cold stress can occur.