Beyond summer fires: shifting forest fire across European biogeographical regions

Abstract Forest fire regimes in Europe are evolving due to complex interactions between climate change, land use, and management strategies. Traditionally concentrated in Mediterranean countries during the summer, fire activity is increasingly affecting regions and periods not historically considered at risk. In this study, we analyzed 20 years (2001–2020) of satellite-derived weekly forest fire data across five European biogeographical regions—Mediterranean, Atlantic, Alpine, Continental, and Boreal—to detect shifts in fire frequency, size, and extent. Using wavelet analysis and multi-method breakpoint detection on weekly fire metrics (burned area, number, and size), we identified significant temporal and seasonal changes in several regions. Results show a decline in summer fire activity in the Mediterranean and Atlantic regions, likely reflecting improved fire suppression and prevention. In contrast, our results show that the Alpine region shows increasing fire activity, particularly outside the summer season, suggesting an expanding fire season linked to climatic and ecological changes. Smaller but notable changes were also detected in Boreal and Continental regions. Our findings highlight the growing relevance of fires occurring outside the summer season in shaping Europe’s fire regimes. These results underscore the need for adaptive, region-specific fire management strategies that account for shifting seasonality and emerging risks beyond the traditional summer fire window.