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People Cause More Fires In The Sierra Nevada Than Lightning, Study Shows

Mar 1, 2017

A new study about how wildfires are started in the US found that people are responsible for more fires than lightning. FM89’s Ezra David Romero reports.

 


Of the 1.5 million fires the study looked at from 1992 to 2012 84% were started by people. University of Massachusetts at Amherst researcher Bethany Bradley says that’s helped tripled the length of fire season in the US, and grow the affected area by seven times. She says fires caused by lightning usually happen in the late summer.

 

“When you introduce humans to the landscape we’re igniting fires basically from January 1st until December 31st," says Bradley. "So we’re vastly expanding where these fires could occur.”

 

"It's these really obvious places where people are that's where the fires are starting." - Bethany Bradley

Bradley says lightning sparked fires tend to start in uninhabited areas, but fires set off by people usually take place near where people live and camp.

 

"Humans are starting larger and larger fires in the springtime and we think that actually part of the reason for that is because of wamer and drier conditions," says Bradley. "It's basically shifting the summer time earlier. Spring is happening earlier, summer is happening earlier and we're the cause of all of these spring emissions."

 

She says the Sierra Nevada has more lightning sparked fires than the rest of the country, on average, “but what was kind of interesting was that your area burned numbers are much more heavily weighted towards human."

 

She says that within the 20 years of Forest Service data humans burned 1.2 million acres in the Sierra Nevada where as lightning started fires burned 650,000 acres.

 

"I was looking at the map of the Sierra Nevadas and you can see this nice ring of human campfire started fires surrounding Lake Tahoe," says Bradley.  "You can see them stretching out on the I-80 corridor between Reno and Sacramento. It's these really obvious places where people are that's where the fires are starting."