C-130 pilots with the California National Guard fight the Pier Fire in Sequoia National Forest. It had grown to over 20,000 acres by 5 September 2017. Photo: Tech. Sgt. Jeff Allen / 146th Airlift Wing

By Georgina Gustin
5 September 2017
(Inside Climate News) – Wildfires burned across hundreds of thousands of acres in the American and Canadian West this week, fueled by scorching temperatures that are breaking heat and fire records across the region.In California, while temperatures have eased, at least 15 cities have seen record-breaking heat, and the state has experienced its hottest summer on record. San Francisco hit 106 degrees over the weekend, breaking its previous high by 3 degrees. Stoked by unusually high temperatures, fires burned on thousands of acres just outside Los Angeles, while firefighters in Washington, Oregon and Montana battled dozens of blazes across those states.By the end of the day Tuesday, at least 81 large fires were blazing across 1.5 million acres of the U.S. West, from Colorado to California and north to Washington. Over the Canadian border, British Columbia has already had a record-breaking fire season—and it’s not over yet. Cities including Seattle were shrouded in a smoky fog. In satellite pictures, the smoke could be seen traveling the jet stream and reaching the East Coast.As firefighters battled the blazes, climate researchers pointed to studies finding that a warmed global atmosphere, with increasingly clear human fingerprints, will continue driving a potent mix of heat and dryness that’s projected to escalate in the West.

A forest fire spreads along the Columbia River Gorge on 5 September 2017. Photo: James C. Kling / CC-BY-2.0

“These unprecedented extreme events, on the daily to the seasonal scale, are exactly the types of events that are more likely due to the global warming that’s already occurred,” said Daniel Swain, a climate scientist at UCLA. “That’s not so much a future projection, but an observational reality, and that’s something we expect to increase in the future. When we get these extremes, there’s a human fingerprint.” [more]

Potent Mix of Record Heat and Dryness Fuels Wildfires Across the West