far north It is both a massive carbon sink and a powerful environmental time bomb.Vast amounts of CO are stored in the region2 in the boreal forest and the soil beneath it. Organic peat soils, for example, occupy only 3% of the earth’s land area (there are also some in the tropics), but contain one-third of his carbon of the earth. The Arctic permafrost also prevents rotting that releases clouds of carbon dioxide and methane that heat the planet, and has trapped thousands of years’ worth of plant life.
But scientists have found in a recent paper that wildfires and human interference reduce the ability of northern ecosystems to sequester carbon, threatening to turn them into carbon. sauceAs a result, climate change has accelerated, and the Arctic is already warming 4.5 times faster than the rest of the world, releasing even more carbon. This is a dangerous feedback loop.
In fact, there are now more than 100 wildfires in Alberta, Canada, displacing nearly 30,000 people from their homes. It is an “unprecedented situation” in the region. According to Thompson Rivers University fire scientist Mike Flanigan, the area burned annually in Canada has doubled since the 1970s. (He was not involved in either new study.) “A warmer world means more fire,” he says. “As temperatures rise, the atmosphere becomes much more efficient at sucking moisture out of dead fuel. leads to.”
The northern boreal forest is the largest terrestrial biome on earth. When they burn, they release greenhouse gases from both vegetation and carbon-rich soils. This was quantified in the first new paper published in March. In fact, boreal forest burning releases 10 to 20 times more carbon than fires in other ecosystems.Flames typically account for 10% of global fire CO2 Annual emissions contributed 23% in 2021, thanks to severe heatwaves and droughts.
“We are facing a dangerous positive feedback between climate and boreal fires,” says lead author Bo Zheng of China’s Tsinghua University. “After extreme wildfires, the slow recovery of forest soil microbial communities weakens carbon uptake, making it difficult to fully absorb the large amounts of carbon dioxide released during combustion.” “The carbon dioxide concentration in the atmosphere will rise, accelerating global warming and making extreme wildfires even more likely,” Zheng added.
Zheng’s team found that the geographic extent of northern forest fires has increased since 2000. This surprises her Carly Phillips, a research scientist with the Union of Concerned Scientists who studies these fires but is not involved in the paper. “Given the carbon density of these ecosystems, it leads to massive emissions,” she says.
Climate change makes these fires more likely. As the northern landscape dries up, dead bushes accumulate that are ready to burn catastrophically. Warming also increases the chances of igniting vegetation. The region is getting so hot that lightning, normally a temperate climate phenomenon, is reaching within 300 miles of the Arctic, and Arctic lightning strikes could double by the end of the century. .
