Even limiting warming to 2 degrees C will increase European forest damage by 20%

Science, 2026. DOI: 10.1126/science.adx6329

European forests are already losing ground to wildfires, storms, and bark beetle outbreaks at historically unprecedented rates. Between 1986 and 2020, roughly 180,000 hectares of forest were disturbed annually. A new study projects that even under the most optimistic climate scenario, with warming limited to approximately 2 degrees Celsius, that number will climb to about 216,000 hectares per year by century's end.

Under a scenario where fossil fuel use continues to increase, the figure could nearly double, reaching close to 370,000 hectares per year.

Building a model that captures feedback loops

Predicting future forest disturbances is difficult because forests are complex systems with interacting feedback loops. Fire changes forest structure, which affects susceptibility to insects. Beetle-killed trees become fuel for future fires. Climate change alters tree growth rates, which determines how much fuel is available. Previous models struggled to capture these interactions at continental scale.

The research team, led by scientists at the Technical University of Munich with contributions from the Potsdam Institute for Climate Impact Research (PIK) and numerous other European institutions, addressed this by developing a deep learning framework trained on high-resolution Landsat satellite imagery. The model simulates the interplay between climate change, forest growth, and multiple disturbance types simultaneously.

Fire moves north, beetles move faster

Wildfire emerges as the dominant driver of disturbance-induced mortality. The Mediterranean is already fire-prone, but the projections show fire expanding into regions where it has historically been rare. Areas in western and central Europe that currently have limited fire management infrastructure may face a disturbance type they are poorly equipped to handle.

Bark beetle outbreaks are the second major driver, concentrated in temperate central European forests. The mechanism is straightforward: warmer, drier conditions accelerate beetle reproduction cycles while simultaneously stressing trees, weakening their resin-based defense systems. The beetles gain more generations per year while the trees become easier targets.

Southern and western Europe face the greatest projected changes. Northern Europe is expected to be less severely impacted overall, but localized hotspots of increased disturbance are also projected there.

The carbon sink at risk

Christopher Reyer, a scientist at PIK and co-author, highlighted a consequence that extends beyond forestry. European forests currently function as a carbon sink, absorbing CO2 from the atmosphere. If increased disturbances kill enough trees and reduce forest cover, these ecosystems could shift from absorbing carbon to releasing it.

That shift would create additional pressure on other sectors, such as transport and agriculture, to cut emissions more rapidly to compensate for the lost forest carbon uptake. It is a feedback loop: climate change damages forests, which accelerates climate change, which damages more forests.

Caveats and uncertainties

The model was trained on historical satellite observations, and its projections assume that relationships between climate, growth, and disturbance observed in the past will continue into the future. Under unprecedented climate conditions, new dynamics could emerge that the model cannot predict.

The study also does not incorporate changes in forest management practices. Adaptive management, including species diversification, altered harvesting schedules, and improved fire prevention, could mitigate some of the projected damage. Conversely, if management does not adapt, actual disturbance levels could exceed projections.

What the study makes clear is that forest disturbance in Europe will increase under all examined climate pathways. The question is not whether damage will grow, but by how much and how quickly.