Dynamics of fire weather conditions in the mixed forest areas of Belarus and Ukraine under recent climate change

The study examines spatiotemporal distribution of fire weather conditions during the fire seasons of 1990–2020 in the mixed forests areas of the territory of Belarus and Ukraine using monthly mean Fire Weather Index (FWI) averaged for each administrative area in the study region. It was revealed that the lowest FWI values were observed in the northern and northwestern regions of Belarus, the highest values were in the southeast. On the territory of Ukraine, FWI values increase toward the east regions. In the seasonal distribution, the FWI increases from March to May and in the middle of summer the index reaches a maximum in the all regions. Analysis of the FWI dynamics over the five-year periods showed that the frequency of danger fire weather conditions varied from a "very low" level to "moderate" level most of the study period. In the last pentad 2015–2020, "high" fire danger level began to appear in the south of Belarus and in the northern part of Ukraine. During the study period, in some regions of Ukraine, there was a decrease in the frequency of the FWI values of 'low' danger level and its simultaneous increase at the higher levels, in connection with the observed climate change in the region.