From the Rocky Mountains to the Amazon to the boreal stretches of Siberia, vast swaths of forest are being lost to drought and wildfire. Now, recent research is showing that these forests may never return, because the climate that nurtured them no longer exists.
“Forests cover 30% of the planet’s land surface, and yet, as humans heat the atmosphere, some locations where they would have grown now appear too dry or hot to support them,” reports The Guardian.
A 2013 analysis of wildfire sites in the Rocky Mountains found that almost one-third of areas burned since 2000 showed no regeneration “whatsoever,” with flowers and shrubs still remaining where tree seedlings were expected.
“In the Rocky Mountains, estimates hold that by 2050, about 15% of the forests would not grow back if felled by fire because the climate would no longer suit them,” The Guardian writes, reeling off a devastating forecast. “In Alberta, Canada, about half of existing forests could vanish by 2100.”
Meanwhile, in the southeastern United States—a region currently suffering through a megadrought—“as much as 30% of forests are at risk of converting to shrubland or another kind of ecosystem.”
Similar suspicions of a looming “forest mortality tipping point” are assailing researchers studying both the Amazon and the boreal forests of northern Russia.
Since 2010, The Guardian writes, nearly 50% of all trees in the southern Sierra Nevada mountains are dead, taken by either drought, insect infestation, or wildfire.
And almost certain to be lost in this forest apocalypse will be majestic, magical species like the giant sequoia.
Researchers studying carbon emissions are keeping a worried eye on this potential for massive “forest mortality,” as forests currently “absorb around one-quarter” of all anthropogenic emissions each year. Landscapes that have long been reliable carbon sinks could thus become carbon bombs.
The Guardian adds that these projected rates of forest death help explain “why much-touted proposals toplant millions of trees to suck up carbon and ameliorate the climate crisis are encountering skepticism; they won’t work if conditions on Earth don’t allow for forests to reproduce and thrive.”
While acknowledging some truth behind the idea that, in a climate changed world, “forests could find new footholds in places that were formerly too cold or otherwise unsuited to them,” The Guardian throws cold water on that faint hope: “Trees can take centuries to reach maturity, and in terms of global heating, older, large trees store much more carbon than younger, smaller ones,”
That leaves just one solution, the UK newspaper writes. “The best answer to the mortality crisis is to preserve the forests we already have—by cutting carbon emissions.”