By Julie Turkewitz
11 October 2017
(The New York Times) – Intense, fast-moving fires have been raging across much of California since Sunday night. The blazes have barreled through communities like freight trains, turning homes to dust in a blink and leaving at least 21 people dead. The largest of the fires are in the state’s wine country north of San Francisco.“We’ve never seen anything like this,” said Trina Grant, 40, who grew up in California but was not prepared for the ferocity of this year’s fire season. Her parents, Arthur and Suiko Grant, died on Monday when flames consumed their home.

Why have these fires been so destructive?

Wildfires often break out in California in October after the state’s dry, sunny summers. The fires are worse this year because of record heat over the summer and high winds now, which can swiftly turn the smallest fires into fast-moving infernos.Weather experts note that this year’s outbreak was a long time in the making.Drought parched California for years, leaving it littered with fuel in the form of dry vegetation. Then the winter of 2016 and the spring of 2017 brought record amounts of rainfall, which spurred new plant growth. That was followed by months of extreme heat that withered the new growth and turned it into more tinder.Finally, the autumn winds from the northeast, known as diablo winds, began blowing through the region over the weekend at speeds of 70 miles an hour or more.All of this is happening in a region where more people are building homes tucked into forests. […]

Aerial view of the Coffey Park neighborhood in Santa Rosa, after wildfires swept through, 10 October 2017. Photo: Douglas Thron

What’s the role of climate change here?

Fire seasons in general have grown longer and more destructive in recent decades, something scientists attribute in part to increased dryness caused by warming temperatures. It is less clear, however, whether the season for this kind of wind-driven fire in California has lengthened.Researchers from the University of Idaho and Columbia University published a study last year saying that climate change had caused more than half of the dryness of Western forests since 1979.Parched landscapes can increase fire size and duration, said Scott L. Stephens, a professor of fire science at the University of California, Berkeley.But it is important to note, he added, that climate change is not necessarily causing specific fires to occur. Wildfires are a natural part of a forest’s life cycle and have been part of the state’s history since long before anyone called it California. [more]

California’s Wildfires: Why Have They Been So Destructive?