Prior low-severity fires reduce the risk of persistent forest loss from subsequent fires

Abstract

Intensifying fire regimes threaten forests globally1,2, but the risk of persistent post-fire forest loss3,4 and its potential mitigation remains poorly quantified. We analyzed millions of wildfires worldwide from 2001 to 2024 and tracked recovery in satellite-observed forest structure and ecosystem function5,6. Post-fire persistent forest loss, indicated by modeled non-recovery to pre-fire conditions over decadal timescales, affected 57.1% ± 1.4% (mean ± s.e.) of burned forest area globally since 2001, with hotspots in Pacific temperate and southern boreal forests. We then identified “crucial fires” as events exceeding a stringent modeled-risk probability threshold for persistent structural or functional non-recovery, with fire severity strongly predicting this loss. This severity dependence revealed a management pathway, as locations with prior low-severity fire experienced lower severity in subsequent wildfires7–9 and had lower modeled probability of becoming crucial. Under a model-based counterfactual scenario, applying the estimated severity attenuation was associated with a 7.6 ± 0.6% reduction; the top 1% of road-accessible areas accounted for 35% of this reduction. These results provide a global framework for identifying where wildfire threatens forest resistance and where targeted low-severity fire management like prescribed fire8,10 might be used to combat global forest loss.