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Up against the ferocity of fire, it is easy to feel that forces beyond our control are at work. In the middle of the worst wildfire season in memory in California, there is a great sense of powerlessness in the face of nature.

Yet, almost every fire, as we detailed this week, is ignited by a person — either by mistake or on purpose.

A flat tire on a trailer drags against the asphalt, sending a spark into dry vegetation and setting a racing inferno that kills people and destroys homes. That is how the Carr Fire began. A person with a hammer is believed to have mistakenly set the fires of the Mendocino Complex blaze, now the largest in California history.

Scientists agree that extreme weather patterns brought on by climate change have made fire seasons more destructive, partly by drying out more vegetation that serves as the fuel for wildfires.