Perilous Times and Climate Change
Climate change causing more violent wildfires: study
By Amy Minsky, Postmedia News December 8, 2010
Climate change is causing wildfires in the North to burn more
violently, which could cause global warming to snowball as it feeds off
its own byproducts, according to research released Monday led by an
assistant professor at the University of Guelph.
The "runaway scenario" hinges on the fact that the fires are pumping
significantly more greenhouse gases into the atmosphere than previously
thought, said Merritt Turetsky, who teaches in the university’s
department of integrative biology.
The increased gases result in more warming which, in turn, leads to
fiercer fires and, again, more gases, she explained.
The team of researchers published their findings of this damaging and
potentially widespread effect of climate change as delegations from
nearly 200 countries gather in Cancun, Mexico to draft a
legally-binding environmental treaty with a focus on curbing global
warming.
"Just a few degrees of warming of the Earth’s surface is going to have
really fundamental shifts for Canadians, like increased droughts in the
summer, longer snow-free seasons, and changes in agriculture," Turetsky
said. "People hear a lot about climate change, but if they take it more
seriously, if they understand it can impact their lives directly, I
think politicians will get the idea that they need to start reflecting
those societal concerns."
The impacts of global warming are felt particularly sternly in the
North, she said, explaining that the higher volume of greenhouse gas
emitted from fires is a consequence of the thawing of the northern
soil, known as permafrost.
Carbon has been accumulating in the northern permafrost and peatland
soils for thousands of years. About half of the world’s soil carbon is
locked in that ground.
"The ecosystems are burning more severely, initiating the permafrost
thaw and making a lot more carbon available for burning in the future,"
Turetsky said.
This study is another drop in much larger and growing body of proof
that climate change is having dire effects in northern regions, the
researchers said.
And although it’s not impossible to break the cycle these researchers
uncovered, it’s unlikely, Turetsky said.
"Given the current structure of the boreal forest, it’s not likely,"
she said. "For anything to change the track of this runaway train, the
boreal forest would have to act very differently than it does today."
But the cycle won’t go on indefinitely, said Eric Kasischke, a
professor of biogeography at the University of Maryland who started
this research project in the early 1990s.
The runaway scenario will probably continue for several decades and
eventually lead to a complete shift in forest type, which will also
lead to fewer fires, he said.
But such a shift will have a cascading effect on all living organisms
in the North, he warned.
"The shift can destroy the habitat for the caribou, for example. So
those populations are likely to drop, and moose populations are likely
to increase, because they like the shrubs that come back after the
severe fires," Kasischke said.
"And eventually it will affect people living in the higher northern
areas, as they’re forced to shift their resources and refocus their
hunting habits."
To collect the data for this study, which will be published in Nature
Geosciences, researchers visited almost 200 sites in Alaska shortly
after fires had been extinguished, and measured the amount of biomass
that had burnt.
The group is undertaking similar studies in the Canadian boreal forests.