The boreal forest, 也称为 “taiga,” is the world’s largest and most intact biome, forming a sprawling, dense ring of woodlands situated below the Arctic circle and spanning vast tracts of the Northern Hemisphere in North America, Europe and Russia. This ecosystem — with trees like spruce, pine, and fir — make up about one-third of all forests on the planet.
在过去, researchers have called the boreal forests
“the carbon the world forgot
,” because it stores roughly
30 至 40% of all land-based carbon in the world
, mostly tucked in the soil
. The northern hemisphere’s cold temperatures prevent dead biomass from breaking down
, storing carbon for thousands of years deep in the permafrost
But as climate change and industrial activities advanced deeper into the vital ecosystem
, degrading the land and spewing more planet-warming gases that fuel devastating wildfires
, many climate researchers fear that the boreal could reach a tipping point
, beyond which they shift from absorbing carbon dioxide from the atmosphere to emitting it
The boreal forests are warming twice as fast as other parts of the world
. 这些年来, researchers say it has become a vicious climate change feedback loop
: the emissions from wildfires contributes to increasing global temperatures
, which in turn fuel wildfires
“One of the challenging and interesting things about wildfires right now is that they are both driven by climate change and drivers of climate change,” 菲利普斯说.
The burned area in the Alaskan boreal forests could increase as much as 169% 通过 2050, the study notes, while burned area in the Canadian boreal could expand by up to 150%.
Philips says their findings are likely conservative estimates, considering they did not assess rapid permafrost thaw and other harmful greenhouse gases emitted from the fires including methane and nitrous oxide, which lead to higher atmospheric temperatures.
“We know that the implications of wildfires in these areas is that there can be feedbacks to permafrost thaw and as a result, the exposure and release of that anciently stored carbon,” 她说. “Secondly, we are only accounting for the direct emissions from the fire and then regrowth but we aren’t accounting for the decomposition that can occur after the fire.”
一个 recent UN report
, which found that the number of extreme wildfire events globally will increase by up to
30% 通过 2050, said that it’s time for the planet to adapt and
“learn to live with fire
” through better fire management practices to prevent more lives and economies from being put in harm’s way
仍然, Phillips and her colleagues found the North American boreal forests disproportionately receive little funding for fire management efforts. 根据报告, Alaska accounts for about 20% of the country’s burned land area as well as half of its fire emissions annually, yet the state only receives roughly an average of 4% of federal fire management funding.
“We’re now seeing the smoke from these fires move across the world, and so that really underscores that this is a global issue, while some of the most detrimental impacts are localized,” 菲利普斯说. “The effects of these fires is of global significance. And this is an opportunity for us to address these heat-trapping emissions that are coming out of these wildfires.”