Increasing lifetime exposure to extreme fire weather under climate change in Europe

Climate change increases fire weather globally. Hot, dry and windy conditions raise the likelihood of fires igniting and spreading and make suppression more challenging. With further warming, fire weather is projected to intensify across Europe, yet implications for today's young generations remain unclear. Here, we analyse lifetime exposure to extreme fire weather across Europe using an ensemble of bias-adjusted and downscaled global climate models. To this end, we developed dem4cli, an open-source Python package that integrates demographic data into climate hazard assessments. We find younger generations are projected to be disproportionately exposed compared to older generations across all warming pathways, while also benefitting most from ambitious mitigation. Across Europe, individuals born in 2025 are projected to experience, on average, 3.2 additional years of exposure to extreme fire weather compared to those born in 1950, corresponding to an 84% increase, with larger increases observed in Southern and Eastern Europe. Focusing on Portugal, under current policies, people born in 2025 are projected to experience nearly twice the exposure compared with those born in 1950, and up to 2.5 times more in the most exposed regions of northeastern Portugal. Under a 1.5 ${}^{\circ }$  C pathway, lifetime exposure is substantially reduced. Each additional degree of global warming by 2100 adds approximately 270 days of extreme fire weather to the lifetime exposure of a person born in Portugal in 2025. These results reveal pronounced intergenerational inequalities in exposure to fire weather and underscore the urgency of ambitious mitigation to limit cumulative exposure for younger generations.