Climate change is leading to unprecedented damage from wildfires

Wildfires boosted by climate change are burning twice as much tree cover around the world as it was 20 years ago, according to data Wednesday showing the equivalent of 16 football fields is being lost every minute.

The research showed in unprecedented detail how wildfires have evolved over the past two decades, with the blazes claiming an estimated three million hectares more each year – an area the size of Belgium – compared to 2001.

The study showed that most of the tree cover loss is occurring in the boreal forests that cover much of Russia, Canada and Alaska, which are among the world’s largest carbon sinks.

University of Maryland researchers used satellite imagery to map areas of lost tree cover, including those burned by so-called stand-replacement wildfires.

These are fires that destroy all or most of the forest canopy and permanently alter forest structure and soil chemistry.

The data showed that 2021 was one of the worst years for wildfires since the turn of the century, destroying 9.3 million hectares of trees worldwide.

That was more than a third of all forest lost last year, according to data compiled by Global Forest Watch and the World Resources Institute research group.

“Wildfires are getting worse around the world,” James McCarthy, research analyst at Global Forest Watch, told AFP.

The European Union’s satellite monitoring service said last week that western Europe has seen record fire activity so far in 2022, with tens of thousands of hectares of forest lost in France, Spain and Portugal.

The researchers said climate change is likely a “main reason” for the increased fire activity, with extreme heat waves already five times more likely to dry out forests than they were a century and a half ago.

These drier conditions lead to higher emissions from fires and exacerbate climate change as part of a “fire-climate feedback loop,” they said.

The vast majority — about 70 percent — of fire-induced tree cover loss over the past two decades has occurred in boreal regions, likely because the high-latitude regions are warming faster than the rest of the planet.

Last year, Russia lost 5.4 million hectares of tree cover to fires, up 31 percent from 2020, the highest on record.

“This record-breaking loss was due in part to sustained heat waves that would have been virtually impossible without human-caused climate change,” the study said.

The team warned that increasing changes in climate and fire activity could eventually turn boreal forests from a carbon sink into a source of carbon emissions.

“In these boreal regions, soil carbon has accumulated over hundreds of years and has been protected by a moist layer above,” McCarthy said.

“These more frequent and more severe fires burn up that top layer and expose that carbon in the soil.”

This century, fire-related tree cover loss in the tropics has increased by about 5 percent — about 36,000 hectares — a year, the study showed.

Fire is not the main cause of forest loss in these regions, with deforestation and forest degradation being the main causes.

But the researchers said forest loss from deforestation made it more likely that forests would be lost to fire, as the practice leads to higher regional temperatures and drier vegetation.

They called on governments to improve forest resilience by ending deforestation and curbing local forest management practices, including controlled burning, which can easily get out of control, especially during dry spells.

“Forests are one of the best defenses we have against climate change,” McCarthy said.