US President Donald Trump has arrived in California to be briefed on wildfires engulfing swaths of the west coast of the country, telling officials that global warming will reverse itself.
The quick stop during a three-day reelection campaign swing was the first time Mr Trump has visited California since the devastating blazes began.
Earlier, Democratic challenger Joe Biden branded Mr Trump a "climate arsonist" whose policies are contributing to evermore powerful natural disasters.
On arrival in McClellan Park, near Sacramento in central California, Mr Trump repeated his argument that the ever-growing danger from wildfires in places such as California, Oregon and Washington is due to insufficient maintenance of forest areas to make them less combustible.
"There has to be strong forest management," he said.
"With regard to the forests, when trees fall down after a short period of time, about 18 months, they become very dry. They become really like a match stick," he said. "They just explode."
Mr Trump met California Governor Gavin Newsom, who has strongly argued that the fires are driven mostly by global warming.
Mr Newsom acknowledged that "we have not done justice on our forest management", though he pointed out that more than half of the land in California is under federal, not state control.
But he said the overwhelming cause of the problem is far bigger.
"The hots are getting hotter, the dries are getting drier," he said.
"We submit the science is in and observed evidence is self-evident: that climate change is real and that is exacerbating this."
Mr Trump later suggested that global warming will reverse itself, saying the climate will "start getting cooler".
He brushed aside concerns about climate change, saying: "It will start getting cooler. You just watch."
Wade Crowfoot, the head of the California Natural Resources Agency, responded: "I wish science agreed with you."
"I don't think science knows, actually," Mr Trump responded.
California Natural Resources Secretary @WadeCrowfoot: "We've had temperatures explode this summer..."
— CSPAN (@cspan) September 14, 2020
President Trump: "It'll start getting cooler, you just watch."
Crowfoot: "I wish science agreed with you."
Trump: "I don't think science knows, actually." pic.twitter.com/xJPYoTjJBo
Mr Biden had earlier slammed his presidential rival as a "climate arsonist" whose refusal to take global warming seriously would exacerbate the crisis if the Republican incumbent is re-elected in November.
"If you give a climate arsonist four more years in the White House, why would anyone be surprised if we have more of America ablaze?" Mr Biden said, savaging Mr Trump for failing to "take responsibility" for the ongoing wildfire crisis.
He added: "We need a president who respects science, who understands that the damage from climate change is already here.
"We can commit to doing this together, because we know that climate change is the existential challenge that is going to determine our future as a country.
"Or we can do it Donald Trump's way: ignore the facts, deny reality, which amounts to a full surrender and a failure to lead."
Wildfires have ravaged parts of California, Oregon and Washington, so far leaving at least 35 people dead and burning nearly five million acres.
