Published on April 12th, 2017 | by James Ayre0
Study: Large, High-Intensity Wildfires To Become Much More Common In Coming Years
April 12th, 2017 by James Ayre
There will be a large increase in the number of large, high-intensity forest fires that occur in the coming years and decades, according to new research led by South Dakota State University professor Mark Cochrane.
The findings are the result of an analysis of around 23,000 fires that occurred worldwide between the years of 2002 and 2013 (using satellite data), including 478 “large, high-intensity” fires that were classified as being extreme wildfire events.
“Almost all happened under bad conditions — high temperatures, dry conditions, and strong winds, which tell us that weather and climate are very important,” stated Cochrane.
The researchers used monthly world weather data from 2000 to 2014 to create a model of the changes to fire behavior that are likely from 2041 to 2070 — with the result being a 20–50% increase in the number of days when the conditions that accompany large fires are present.
“Those conditions are based on business-as-usual carbon emissions,” Cochrane stated. “This will continue to worsen after 2070 unless we get very serious about cutting global carbon emissions.”
To put the findings a different way, by 2041, there are expected to be around 35% more large, high-intensity fires per decade (on average).
Cochrane continued: “That translates to 4 extreme fire events for every 3 that occur now.”
The press release provides more:
However, that risk is not spread evenly, Cochrane explained. Forests in the western United States, southeastern Australia, Europe, and the eastern Mediterranean region that extends from Greece to Lebanon and Syria are among those areas at highest risk.
Though the concept of huge, devastating wildfires, sometimes called megafires, has been tossed around, Cochrane said, ‘There is no operational definition.’ Therefore, the research team, led by University of Tasmania professor David Bowman, examined fire intensity and area.
First, the researchers identified hotspots using moderate resolution imaging spectroradiometer, or MODIS, from two earth-imaging satellites to measure the amount of heat energy released, known as fire radiative power. To do this, they looked at the total energy being released in each 25,000-acre block across the planet… Through that analysis, the researchers identified 478 extreme fire events.
We limited ourselves to the top .003%,” Cochrane continued. “Anyone would agree that these are pretty intense, large events.
This was then further refined by focusing on the fires that affected people the most (e.g., no boreal forest fires in nearly uninhabited regions). This led to the identification of 144 fires that were considered to be “catastrophic” (people dying, homes being destroyed, etc.).
“Most of these fires were in the western United States and southeastern Australia, which have fairly high population densities,” Cochrane noted. “Not only is climate making things worse, but people are building homes in these flammable landscapes.”
The new work is detailed in a paper published in the February 2017 issue of Nature Ecology and Evolution.