100 million tons per year: the CO₂ that Europe's forests can no longer absorb

Cerdanyola del VallèsForests, key allies in the fight against climate change due to their ability to absorb carbon dioxide (CO₂), are losing effectiveness in Europe.

However, a study published in the journal Nature, led by Mirco Migliavacca, a researcher at the Joint Research Centre, in collaboration with the Center for Ecological Research and Forestry Applications (CREAF) and the CSIC, warns that this carbon sequestration capacity is clearly declining. The research shows how annual forest carbon absorption in Europe has fallen from 457 million tons of CO₂ between 2010 and 2014 to 332 million tons absorbed each year between 2020 and 2022. This represents a reduction of nearly 30% in just one decade, but data for 2025 "are in line with the same trend, and the decline could be even greater."

This decline seriously jeopardizes the European Union's climate objectives, which have pledged to achieve climate neutrality by 2050. Within this framework, a target of absorbing 310 million tons of CO₂ had been set for 2030, a figure that, in view.

Causes beyond climate change

The causes behind this decline in the carbon absorption capacity of European forests are multiple and interrelated. Peñuelas points out that among the main causes is "the increase in tree felling," driven by growing demand at the European and global scale and the increase in natural disturbances such as fires, storms, and pests, often followed by premature removal of dead or burned wood. Furthermore, the reduction in reforestation and the aging of forests also limit their growth and capacity to absorb CO₂.

Peñuelas also highlights that "increasingly frequent heat waves and droughts reduce tree growth" and directly affect their productivity, as well as "the increase in fires, pests, and storms, which increase tree mortality."

Smart forest management to reverse this

The study's authors propose "implementing integrated policies" to address the problems facing Europe's forests. The CSIC researcher points out that these policies should be aimed, first and foremost, at "improving the monitoring and tracking of carbon flows and the health of our forests, not just those in Catalonia, but all European forests, through the combined use of satellite and ground-based data."

In parallel, the study advocates a profound transformation in the way European forests are managed. Forest management must have objectives beyond producing wood. "We must commit to sustainable and climate-smart management that considers forests as spaces that provide us with many more services beyond wood production, such as soil protection, regulation of the water cycle, and habitat for fauna and flora. And we must understand that forests with more species and with structures that are more resilient to climate change," Peñuelas points out.

The study proposes a balance between productive activities, such as logging, and the conservation of natural habitats, and recommends forest management that combines forests of different ages and levels of protection. This would alternate areas designated for sustainable production with strict conservation zones, which promotes biodiversity and helps maintain carbon stored in living wood, dead wood, and soil.

Regarding reforestation, experts warn that it will be essential to carefully select locations for planting new trees in Europe, as water scarcity will determine the success of these initiatives. Therefore, this strategy will only be viable in areas with favorable climatic conditions.