SACRAMENTO (California) • Wildfires that have already destroyed at least half a dozen small towns in the north-western United States raged largely uncontrolled on Friday as California's governor called the fire season evidence of a climate emergency.

Fires in California, Oregon and Washington have torn through idyllic mountain towns, reduced neighbourhoods to ash and spewed so much smoke that pilots were unable to pursue aerial attacks that can be critical in preventing such mass wildfires from encroaching on communities.

Combined, the states have seen nearly 2 million ha consumed by fire - a land mass approaching the size of New Jersey - in a record-setting year that scientists think portends the types of disasters that will become more common on a warming planet.

"This is a climate damn emergency. This is real and it's happening. This is the perfect storm," California governor Gavin Newsom told reporters from a charred mountainside near Oroville, California.

He acknowledged that poor forest management over decades had contributed to the severity of the state's wildfires in recent years.

But he said serious droughts and record-breaking heat waves were undeniable evidence that many of the most dire predictions about climate change had already arrived.

"California is America in fast forward," he said. "What we're experiencing right now is coming to communities all across the country."

The fires have caused the loss of hundreds, if not thousands, of homes, most of them in Oregon, where an estimated 40,000 people have been evacuated and as many as 500,000 live in evacuation alert zones, poised to flee with a change in the winds.

REUTERS, NYTIMES

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