Did you know…
Wildfires are not just a result of climate change, they’re also contributing to it much more than imagined.
This is because burning vegetation releases stored-up carbon into the atmosphere. The release of carbon speeds global warming and exacerbates conditions that lead to more wildfires.
For example, large wildfires around the globe are transforming the boreal forest. The boreal forest is the world’s largest land-based habitat, or biome. Spreading over several continents, and representing 29% of the world’s forest cover, the boreal plays a significant role in the Earth’s biodiversity and climate.
In fact, according to the research scientists at National Geograhic, climate change is playing out twice as fast in the Boreal Forest than it is on the rest of the planet.
How is climate change affecting the risk of wildfires? First of all, spring runoff is occurring earlier, resulting in a longer fire season. According to the National Wildlife Federation and the Union of Concerned Scientists, global snowmelts are now occurring one to four weeks earlier than they did 50 years ago.
Secondly, drier conditions, particularly in western North America, increase the probability of wildfires.
Summertime temperatures in the western U.S. are projected to be 3.6 to 9 degrees higher by mid-century. This results in increased evaporation rates. At the same time, precipitation is expected to decrease by up to 15%.
Warmer and drier conditions make wildlands particularly vulnerable to insect infestations, resulting in more dead and highly combustible trees.
Outbreaks of forest-destroying plagues have come in the form of spruce-bark beetles, aspen-leaf miners, larch sawflies, and spruce budworms. All of these have been worsening in recent years due in large part to the warming of the average temperature.
In addition, thunderstorms are becoming more severe, increasing the frequency of lightning. A 1.8 degree increase in temperature results in a 6% increase in lightning. This means that lightning in the western U.S. could increase by 12 to 30% by mid-century.
John Holdren, President Obama’s science advisor, has summed up the situation in the following video clip:
According to NASA scientist Peter Griffith, dramatic climate change can be glimpsed from space. Specifically, the tundra is turning green, while the boreal forest is turning brown.
Larger and more frequent wildfires are “putting more greenhouse gases into the atmosphere that would have stayed locked up for perhaps hundreds of years.”
In addition, large wildfires are burning through the peat, the rich organic forest soil that serves as a large reservoir for carbon.
“The warmer the Earth gets, the more fire we get, and the more fire we get, the more greenhouse gases we get.” — Mike Flannigan, University of Alberta-Edmonton
The near-destruction of Fort McMurray in northern Alberta, Canada, is grim proof that the threat to the boreal forest is real.
As one of the largest human outposts in the boreal forest, Fort McMurray was particularly vulnerable And scientists say a large-scale loss of the forest could have profound consequences for efforts to limit the damage from climate change.
“Large-scale (wildfire) events can release huge amounts of carbon dioxide into the atmosphere with one fell swoop.” — Jennifer Balch, National Center for Ecological Analysis and Synthesis, UC-Santa Barbara
According to a recent study, for every degree of global warming, the forest needs a 15% increase in precipitation to compensate for the increased dryness.
Unfortunately, forests are receiving less rain, not more. If that weren’t bad enough, every degree of warming also increases lightning activity by 2%, Flannigan says.
An El Niño weather pattern has been pumping a huge amount of heat from the ocean and into the atmosphere for more than a year. Scientists say that could have played a role in setting the conditions for this year’s fires.
For instance, temperatures in parts of Alberta were as much as 30 degrees above normal in the weeks before the fires. These increased temperatures desiccated the landscape.
So, wildfires apparently hasten ecosystem changes and release large amounts of CO2 into the atmosphere. This contributes to further climate change, which contributes to more wildfire, and so on.
Observed and predicted climate changes are expected to increase in wildfire-prone areas of the United States and elsewhere. But our choices regarding land use and firefighting tactics can also play a role in decreasing (or increasing) wildfire risks.
According to the Center for Climate and Energy Solutions, the following guidelines can help communities, builders, homeowners and forest managers to reduce the likelihood and impacts of wildfires: