Compounding preconditions of wildfires vary in time and space within Europe

Abstract Favorable wildfire conditions are increasing in frequency and severity across Europe. Understanding how wildfire drivers vary in space and time is crucial for mitigating wildfire risk under current and future climate conditions. Here, we analyze the hydro-meteorological and land-surface drivers of wildfires from 2001 to 2020 across eight European climate regions and their mountain ranges. Our findings reveal that drought conditions and vapor pressure deficit are the dominant drivers of wildfire activity. These drivers vary by season and region: in Southern and Central European regions, persistent warm and dry conditions in preceding seasons favor summer wildfires, while fall wildfires are influenced by fuel build up in spring that loses moisture during dry and hot summer weather. In Northern Europe, these dynamics occur on sub-monthly timescales. Our results illustrate the critical role of compounding wildfire drivers and emphasize the need for targeted mitigation strategies, especially in the light of climate change.