California Oak fire remains uncontained as Al Gore warns ‘civilization at stake’

The governor of California, Gavin Newsom, declared a state of emergency for an area close to Yosemite national park, mobilizing thousands to tackle a wildfire that exploded on Friday, quickly grew to more than 14,000 acres and on Sunday remained entirely uncontained.

Discussing the ferocity and fast-growing nature of the blaze, the former vice-president Al Gore, long a campaigner for action on the climate crisis, warned: "The survival of our civilization is at stake."

The US climate envoy, John Kerry, told the BBC the White House was still considering announcing a climate emergency, adding that Joe Biden was prepared to use "every tool available to him" to tackle climate change, including executive orders.

The fire in Mariposa county, California, named the Oak fire, represented a dangerous new front in the fight against wildfires in the western US. The region has already seen blazes accelerated by a long drought, a terrible forewarning of the intensifying effects of the climate crisis.

As the Oak fire grew on Saturday, more than 6,000 people were placed under evacuation orders in the remote region and power was shut off to more than 2,000 homes and businesses. More than 2,600 structures were threatened.

High temperatures and strong winds fueled fire activity, officials from California's department of forestry and fire protection, or Cal Fire, said on Saturday. Spotting, in which embers are carried by the wind, spreading the blaze, was a major factor in the growth of the fire, they said.

On Sunday the temperature was just under 100F (38C). While dramatic smoke formations created by the fire on Saturday had calmed, ashen air cloaked the region, shrouding the Sierra foothills in a thick haze.

Officials said the weather was expected to remain hot with minimal humidity. High tree mortality and dense fuels complicated the firefight, they added.

Hector Vasquez, of Cal Fire Team 5, told the Guardian: "The fire did remain active overnight but there were no structures destroyed overnight.

"We are fortunate enough hay the winds have remained the same," he added, noting that gusts had slowed. Still, Vasquez said, "the fire is burning so intensely that it tends to create its own weather. There is a lot of fuel to be consumed out there."

The blaze continues to tear through dense vegetation, fueled by high temperature and aided by steep terrain that's added complications to containment efforts. The parched landscapes haven't burned in decades, which has enabled overgrowth.

More than 2,000 people were fighting the blaze along with helicopters, other aircraft and bulldozers. The fire blocked one of the main routes into Yosemite, where earlier this month a stand of massive and ancient giant sequoias was threatened by the Washburn wildfire. That blaze burned 4,857 acres and is now 79% contained. The Oak fire was already more than twice the size of the Washburn fire.

"The fire is moving quickly," said Daniel Patterson, a spokesperson for the Sierra national forest, adding that the blaze "was throwing embers out in front of itself for up to two miles yesterday".

"These are exceptional fire conditions," Patterson said.

Gore, who was vice-president to Bill Clinton between 1993 and 2001, spoke to ABC's This Week, repeating his warnings over rising global fossil fuel emissions.

"We're seeing this global emergency play out and it's getting worse more quickly than was predicted," Gore said. "We have got to step up. This should be a moment for a global epiphany."

Climate scientists, he said, have for years warned that "if we don't stop using our atmosphere as an open sewer, and if we don't stop these heat trapping emissions, things are gonna get a lot worse.

"More people will be killed and the survival of our civilization is at stake."

Meteorologists have warned that five high-pressure weather systems across the northern hemisphere, linked by atmospheric waves, are causing temperatures to soar.

A heatwave in Europe, triggering wildfires in France and Spain and record temperatures in the UK, is mirrored by conditions in the US, where cities in Texas and Oklahoma have seen temperature records fall. At least 31 Chinese cities have been placed under heat warnings, according to the China Meteorological Administration.

But calls for legislative action are running up against political and social paralysis. Andreas Malm, author of the book How to Blow Up a Pipeline, called for stepped-up civil disobedience to force governments and companies to act more coherently.

"Climate activists in Europe and across the global north are assimilating and diversifying and escalating into various different kinds of sabotage and interruption," Malm told the Guardian, pointing to campaigns to disable large SUVs across parts of Europe and the US.

"This kind of thing is going to escalate," he added, warning that radical environmental groups were considering "an explicit endorsement of the destruction of infrastructure".

On Saturday, the Oak fire sent up a pyrocumulus cloud so large it could be seen from space. Its smoke plume has darkened skies for hundreds of miles and caused air quality advisories to be issued as far away as Barstow, between Los Angeles and Las Vegas.

Kim Zagaris, an adviser for the Western Fire Chiefs association, told the LA Times: "When you get a pyrocumulus column, it can pick up a pretty good-sized branch and actually draw it aloft into the column and in some cases drop it a mile or two miles down the head of the fire, which starts additional spot fires."

Felix Castro, a meteorologist with the US National Weather Service, said the region had experienced 13 consecutive days of triple-digit heat with relative humidity of 8% or 9%. Vegetation had reached near-record dryness, he said, in what scientists estimate to be the most arid 22-year period in at least 1,200 years.

"Our drought indices are about as low as they can get, including the last two to three years, for much of our region, with the greatest dryness in the Sierra," Castro said.