Warmer, drier climates and higher forest growth rates are factors—linked to the climate crisis—that fuel forest fires, especially in extratropical regions. In these areas, particularly in the boreal forests of North America and Europe, emissions have nearly tripled since 2001
Forest fire emissions have increased by about 60% from 2001 to 2023. This is a global average that hides a new trend: it is the boreal forests, not those in tropical regions, that are burning more. In the case of the forests of North America and Europe, emissions have nearly tripled in 23 years.
Two consequences of the climate crisis, which is progressing twice as fast in these latitudes compared to the global average, are the main drivers.
On the one hand, the increase in emissions is linked to increased fire-favourable climatic conditions. Due to global warming, warmer and drier periods, especially during heatwaves and droughts, are becoming more intense and frequent. On the other hand, forest growth rates are also rising. The climate crisis also plays a role here: increased CO2 levels are stimulating tree growth.
This is not the only significant trend emerging in recent decades. The scale of wildfires is increasing, as is their severity. This is indicated by the rising trend of the carbon combustion rate, a measure of wildfire severity based on the amount of carbon emitted per unit of burned area. This indicator has increased by almost 50% in forests worldwide between 2001 and 2023.
also read Forest ecosystems and climate change
Forest fire emissions: consequences for carbon budgets and reforestation credits
This is the conclusion of a recent study published in the journal Science, conducted by scientists from the University of East Anglia, UK. It is the first study to compare changes in forest fire emissions with those from non-forest fires, identifying trends at both regional and cluster levels.
One key consequence of this research is the need to rethink how wildfire emissions are currently attributed to natural versus non-anthropogenic causes. Perhaps more importantly, the findings have implications for the integrity of the emission budgets submitted by countries to the UN and for the reforestation-based carbon credit market. In both cases, carbon reservoirs are more exposed and may prove to be less enduring than currently believed.
