Americans are torching their own country annually. While climate change has exacerbated fire season, researchers haven't really studied how many of those fires are Americans' own damn faults until recently.
Image: John McColgan/Wikimedia Commons
The answer is most of them -- 84 per cent.
A team of American scientists reviewed a million and a half US government records on the bushfires that states needed to put out between 1992 and 2012. Humans were responsible for almost 1.25 million bushfires, while lightning was only responsible for the remaining 250,000. Human-burned area amounted for a little less than half of the total burned area, though, since lightning-caused fires generally happen in the wilderness and burn out on their own, according to ClimateCentral.
"The role that humans play in starting these fires and the direct role of human-ignitions on recent increases in wildfire activity have been overlooked in public and scientific discourse," the scientists write in a paper published in the Proceedings of the National Academy of Sciences today. It's often difficult to attribute fires to human activity or lightning.
The researchers took their data from the US Forest Service Fire Program Analysis-Fire Occurrence Database -- and the causes of the fires were unsurprising: "[E]quipment use, smoking, campfire, railroad, arson, debris burning, children, fireworks, power line, structure, and miscellaneous fires." Arson and lightning accounted for the same number of fires, according to ClimateCentral.org's reporting. Think about that: Humans set as many criminal fires as nature would have lit alone.
And things have been really bad. Four of the worst fire seasons in the US since 1960 have happened in the past 10 years, with over 10 million acres set ablaze in 2015, according to a paper published by bushfire experts back in 2015. This past year saw flames destroying 80,000 acres and killing 14 in the Southeastern United States, and those fires were set by a couple of kids. Fire destruction amounted to around $US2 billion ($2.6 billion) worth of destruction in 2016.
Bushfires are actually necessary for the environment. Trees in the US Northeast's pine barrens require fires to produce their seeds, for example, according to Timothy Mihuc, a professor of environmental science at SUNY Plattsburg in New York. Except now there are far more human-caused bushfires than lightning-caused bushfires, and in areas with higher populations.
So, guys, put out your campfires, don't toss your cigarette butts into piles of kindling, don't set your neighbours' lawns on fire, et cetera. Only humans can prevent bushfires, because mainly humans have been starting them.