Global wildland fire season severity in the 21st century

We used Cumulative Severity Rating (CSR), a weather-based fire danger metric, to examine the potential influence of climate change on global fire season severity. The potential influence of climate change on fire season length was also addressed. We used three General Circulation Models (GCMs) and three emission scenarios to calculate the CSR and fire season length for mid-century (2041–2050) and late century (2091–2100) relative to the 1971–2000 baseline. Our results suggest significant increases in the CSR for all models and scenarios. Increases were greatest (more than three times greater than the baseline CSR) for the Northern Hemisphere at the end of the century. Fire season length changes were also most pronounced at the end of the century and for northern high latitudes where fire season lengths will increase by more than 20 days per year. The implications from this study are that fire seasons will be more severe in future and that conventional fire management approaches may no longer be effective.

► Using multiple GCMs and scenarios we anticipate significant increases in global fire season severity this century.
► Fire season length is expected to increase by more than 20 days for high latitude northern regions by the end of the century.
► Larger and more intense fires are expected in a future warmer world.
► Fire management will be even more challenging will these increases in fire activity.