Alastair Gee and Dani Anguiano wrote a book about the Paradise Fire. They tell us some things:

Prior to European settlement in the West, fire flowed freely, sparked by lightning or intentionally by Native Americans to encourage the growth of favored plants or clear areas for easier hunting. As much as 4.5m acres of California’s 105m acres might burn every year. These low-intensity fires did not kill large trees, and some plants even came to depend on fire to regenerate themselves. A shrub called chamise appears to encourage fire by releasing combustible gases in the presence of flames.

The shift to a different approach occurred after several instances in which wildfires became appalling urban fires. In October 1871, railway workers sparked a brush fire in northern Wisconsin, which swept into the city of Peshtigo and killed 1,500 people there and elsewhere across a gargantuan footprint of 1.2 million acres. And in the great fires of 1910, fires burning across several Western states killed hundreds and razed a number of towns. People escaped by train as the fires virtually licked at their heels.

So the US decided no more out of control fires.

Fire activity decreased, it is true, but with scouring flames removed from the environment, forests grew far denser and brushier than they had been before. In one Arizona forest, 20 trees per acre became 800 trees per acre. These forests can and will burn more severely. In addition the climate crisis is rendering vegetation ever drier, and by 2050 up to three times more acreage in Western forests will burn as a result of global warming. Meanwhile 60m homes can now be found in or close to high-risk areas where wildfires have previously burned.

Cue urban fires. The fire that obliterated Paradise on the morning of November 8, 2018 was sparked in a rural river canyon several miles to the east of town. As we describe in our new book, Fire in Paradise: An American Tragedy, it approached the community at speeds previously thought impossible, chewing through almost 400 American football fields’ worth of vegetation per minute. It hit like a hurricane. Strikingly, many of the hundreds of thousands of trees in the town were spared – it was the homes that became matches setting fire to the next. The fire was so quick, so hot, that people died seeking shelter under their cars, in the driveways of their homes while holding a hose, or huddled in their bathtub.

They go on to say it could happen anywhere, including in big cities.