Damage to European forests from increased logging, wildfires, drought and pests is reducing their ability to absorb carbon dioxide, putting European Union emissions targets at risk, scientists warned on Wednesday.
The European Union has committed to reaching net zero emissions by 2050. The target includes the expectation that forests will suck up hundreds of millions of tonnes of CO2 emissions and store it in trees and soil, to compensate for pollution from industry.
But that assumption is now in doubt. The average annual amount of CO2 Europe's forests removed from the atmosphere in 2020-2022 was nearly a third lower than in the 2010-2014 period, according to a paper led by scientists from the EU's Joint Research Centre - its independent science research service.
In the later period, forests absorbed around 332 million net tonnes of CO2 equivalent per year, said the paper, published in the journal Nature. Recent data from EU countries suggest an even steeper decline.
"This trend, combined with the declining climate resilience of European forests, indicates that the EU's climate targets, which rely on an increasing carbon sink, might be at risk," the paper said.
Today, Europe's land and forestry sector offsets around 6% of the EU's annual greenhouse gas emissions. That's 2% short of the amount the EU calculates is needed to meet climate goals - with the gap expected to widen by 2030.
Agustín Rubio Sánchez, professor of ecology and soil science at the Polytechnic University of Madrid, said it was "wishful thinking" to rely on forests to meet climate targets.
"Forests can help, but they shouldn't be assigned quantities to balance carbon budgets," he told Reuters.
The findings are a political headache for EU governments, who are negotiating a new, legally-binding 2040 climate target - which is designed to use forests to offset pollution that industries cannot eliminate.
Already, some are warning this won't be possible.
"What should we do when there are factors that we, as countries, as governments, have not much ability to control - like forest fires or drought," Sweden's environment minister Romina Pourmokhtari said in a news conference last week.
Over-harvesting, climate change-fuelled wildfires and droughts, and pest outbreaks are all depleting forests' carbon storage.
However, some of these risks can be managed - for example, by reducing intense logging, or planting more diverse tree species, which may enhance CO2 storage and help forests withstand climate extremes and pests, the paper said.
