European forests have been losing more biomass since 2018 and storing less CO₂

Europe's forests are losing more biomass than previously thought, and disturbances such as drought and pest infestations are causing increasingly severe losses in some of Europe's oldest forests. Absolute severity measures the amount of above-ground biomass lost following a disturbance such as wind damage, fire, insect infestation or logging. They found that, for every hectare of forest affected, 46% more biomass has been lost since 2018. Relative severity measures the percentage of biomass lost compared with the amount recorded before the disturbance or harvesting took place. By overlaying the two maps, the team reconstructed the actual amount of biomass lost from Europe's forests year by year.