People caused most of California's wildfires over the past 30 years

The vast majority of the more than 250,000 wildfires that blazed through California over the past three decades were caused by people.

Why it matters: With climate change increasing wildfire risk in the West, fires can quickly spread, destroy property and become deadly.

• Changing human behavior could help reduce the devastating threat.

By the numbers: About 86% of wildfires in California between 1992 and 2020 were spurred by human activity, burning 63 acres on average, U.S. Forest Service analysis of wildfire data found.

• Meanwhile, Cal Fire officials say 95% of fires are human-caused currently.

Of note: Lightning strikes accounted for the other fires with known causes, mostly in the northeastern and mountainous parts of the state that border Nevada.

• Lightning strikes were behind California's largest fires, which took place in August 2020, burning more than 2 million acres combined — that's about three-quarters of the size of San Diego County.

Details: The top three human activities known to have led to these blazes were from equipment and vehicles, arson and debris burning, the data shows.

• That includes accidental incidents and neglect, such as leaving a campfire unattended or a malfunctioning catalytic converter spitting a molten substance out of an exhaust pipe.

Between the lines: While firearms and explosives caused 0.2% of wildfires, they led to the largest human-caused blazes, at 380 acres on average.

The big picture: This summer's extreme weather and simultaneous climate disasters are the new reality across North America with unprecedented wildfires, heat waves and storms.

Zoom in: Five wildfires in San Diego County have burned nearly 800 acres so far this year, with three this month.

• The Coyote Fire that burned over 460 acres last week and forced evacuations around Potrero was contained with help from Tropical Storm Hilary.

What they're saying: The San Diego area is particularly fire-prone and susceptible to destructive blazes, partly because there's a lot of rural land in East County, Cal Fire Capt. Mike Cornette told Axios.

• With houses and brush intermixed, it's "more difficult to get in there and defend those homes."
• "And then we get the seasonal Santa Ana winds that can spread those fires very quickly and sometimes outpace firefighters," he said.

Be smart: To help prevent fires, do yard work and agricultural burns with the right tools and avoid hot, dry, windy weather.

• Keep at least a 50-foot buffer around your home as a "defensible space" to create a barrier to slow or stop a fire from engulfing your property.
• Get an evacuation plan in place and have a "go-kit" ready at a moment's notice.