Researchers: Climate Change is Causing More Forest Fires in the West

Last year, we reached a significant and scary milestone: Atmospheric carbon dioxide passed the 400 parts per million level scientists warn we cannot surpass if we hope to avoid the worst climate change impacts. Well, folks, we passed it. And it’s not looking like we will soon drop below 400 ppm. As Ralph Keeling of the Scripps Institution of Oceanography wrote in a blog post: “It already seems safe to conclude that we won’t be seeing a monthly value below 400 ppm this year.”

We are already dealing with the impacts of climate change. A recent study linked an increase in forest fires in the western U.S. to climate change. The study found that changes in temperature and a vapor pressure deficit “enhanced fuel aridity across western U.S. forests” from 2000 to 2015. Aridity is defined by the American Meteorological Society as “the degree to which a climate lacks effective, life-promoting moisture.” Fuel refers to vegetation.

The enhanced dry conditions of vegetation added an average of nine additional days a year of high fire potential in forest areas, researchers concluded. And climate change accounted for 55 percent of the changes researchers observed in fuel aridity from 1979 to 2015 in western U.S. forests. They estimate that climate change “contributed to an additional 4.2 million hectares of forest fire area” from 1984 to 2015, almost doubling the expected forest fire area. And climate change will continue to cause “increases in fuel aridity” and will continue to be a “driver of increased forest fire activity,” the researchers insisted. 

This study is not the first to link climate change to increased risk for forest fires. One study, published in 2014, found “increasing trends in the number of large fires and/or total large fire area per year” in the U.S. Researchers looked at nine different eco-regions in the U.S. and found that the number of large fires increased in seven of those regions. However, they also found that “total fire area trended higher in all nine eco-regions.”

Another study published this year looked at data from 12 weather stations across Canada for fire seasons from 1971 to 2000. Researchers discovered a sensitivity to temperatures increases which “will result in a future with drier fuels and a higher frequency of extreme fire weather days.” A study from 2010 found that future climate change impacts will likely “play a considerably stronger role in driving global fire trends.”

Climate change is linked to extreme weather events

Increased forest fires in the U.S. are not the only climate change impact Americans face today. Extreme weather events are also becoming more frequent. As the U.S. Environmental Protection Agency (EPA) put it: “Climate change is increasing the odds of more extreme weather events taking place.” Heat waves and floods are on the rise, while the frequency of cold waves is dropping.

The National Climate Assessment, conducted by over 300 experts guided by a 60-member Federal Advisory Committee, noted that Americans “are noticing changes all around them.” Some changes are more dramatic than others. Coastal cities are seeing their “streets flood more regularly during storms and high tides.” The effects of Hurricane Matthew are a good example. But coastal cities are not the only ones experiencing floods. Inland cities near large rivers are also flooding more frequently. The summer sea ice in arctic Alaska is receding, and autumn storms are causing more erosion -- which threatens communities with relocation.

We need to reduce emissions and do it now

The fact that we are experiencing the impacts of climate change today means we simply must reduce greenhouse gas emissions. Who we elect for president will decide whether we continue to have a climate change plan. While Hillary Clinton has a plan for climate change, a glance at Donald Trump’s website shows he lacks one. However, Trump has a whole section about energy and advocates that the U.S. unleash “$50 trillion in untapped shale, oil, and natural gas reserves, plus hundreds of years in clean coal reserves.” 

Image credit: Flickr/ Daria Devyatkina