About 16 football fields of trees per minute were lost in wildfires in 2021, says a new report.
Data from Global Forest Watch suggests that, worldwide, the amount of forest cover burned has nearly doubled in the last 20 years.
Climate change is a key factor in the increase as it leads to higher temperatures and drier conditions.
Of the 9 million hectares of trees consumed by fire in 2021, more than five million were in Russia.
The new data allows researchers to distinguish between trees lost in fires and those destroyed for agriculture, logging or during intentional fires.
In 2021, the second worst year of fires on record, an area the size of Portugal was lost.
“It’s impressive,” says James MacCarthy, an analyst at Global Forest Watch.
“It’s roughly double what it was just 20 years ago. It’s surprising how much fire activity has increased in such a short period of time.”
The impacts of fire-related losses are being felt mainly in the forests of countries further north, such as Canada and Russia.
While fire has long been a natural part of how these forests functioned, the scale of destruction seen in Russia in 2021 was unprecedented.
Of the 9.3 million hectares (23 million acres) burned globally, Russia accounted for more than half.
“The most worrying thing is that fires are becoming more frequent, more severe and have the potential to release much of the carbon stored in soils,” said James MacCarthy.
Trees and soils store carbon dioxide – one of the main gases that warm our atmosphere – and experts say it is crucial to combating climate change.
Climate change is seen as a major driver of these fires, with rising temperatures creating drier conditions in which more trees burn.
Northern regions of the world are warming at a faster rate, leading to longer fire seasons.
In Russia, the 31% increase in fire losses in 2021 was in part due to prolonged heatwaves that experts believe would be virtually impossible without human-induced warming.
“Climate change is increasing the risk of hotter, faster and bigger fires,” said Doug Morton, head of NASA’s Biospheric Sciences Laboratory.
“And that is no more visible than forests and woods where you have a lot of fuel to burn.”
In other parts of the world, the impact of deforestation is also leading to more fires.
In the Brazilian Amazon, which recently saw the number of felled trees reach a six-year high, losses due to deforestation and logging are having a knock-on effect.
“Deforestation changes local and regional climates and removes much of the evapotranspiration that helps keep temperatures lower and wetter,” said James MacCarthy.
“So cutting down these forests is actually making them hotter and drier, and making them more fire-prone.”
Although many of the burned trees regrow over a period of about 100 years, there are significant associated impacts of these losses on biodiversity, water quality and soil erosion.
The UN says the outlook for forest fires in the coming decades is bleak. There is an expected 50% increase in extreme fires by the end of this century.
To solve this problem, scientists say that quick and deep cuts in global carbon emissions are critical.
Global leaders at the COP26 climate change conference in Glasgow last year pledged to end deforestation, but the pledge must be honored if it is to make a difference.
More focus is still needed on preventing wildfires rather than fighting them, according to MacCarthy.
“About 50% of national fire budgets are for responding to fires and less than 1% is actually for preparation and planning,” he says.
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