President Donald Trump arrived in California on Monday to meet with officials and to be briefed about the devastating effect of the nearly 90 wildfires plaguing the Western US, after Democrats criticized the president for remaining mostly silent about the current disaster, which includes three of the largest wildfires in state history.

Meanwhile, Democratic presidential candidate Joe Biden gave a speech Monday in which he called Trump a "climate arsonist" for failing to acknowledge the role of global warming in the disaster.

Wildfires across Oregon, California and Washington state have destroyed thousands of homes and a half dozen small towns since August, scorching more than 4 million acres (1.6 million hectares) and killing at least 35 people. Fifty people are reported missing in Oregon alone.

In recent comments, Trump has said poor "forest management" was primarily to blame for the uncontrolled blazes.

Upon arrival in Sacramento to meet California Governor Gavin Newsom amid the smell of smoke in the air, Trump said, brushing off a reporter who asked if climate change was a factor in the fires, "I think this is more of a management situation."

Citing the experiences of other countries, he said: "They have very explosive trees, but they don't have problems like this."

Biden, criticized by Republicans for not visiting disaster areas, spoke from Delaware on the threat of extreme weather that climate scientists have said is supercharging fires.

"If we have four more years of Trump's climate denial, how many suburbs will be burned in wildfires?" Biden asked. "How many suburban neighborhoods will have been flooded out? How many suburbs will have been blown away in superstorms?"

While in California, the president maintained his long-standing position that global warming is a hoax that has little to with the increased frequency of severity of wildfires in recent years.

"It'll start getting cooler. You just watch," Trump said Monday to Wade Crowfoot, a top California state environmental official, during a briefing.

"I wish science agreed with you," Crowfoot responded.

"I don't think science knows, actually," the president said with a laugh.

Campaigning in Nevada over the weekend, Trump blamed forest management for the current crisis. Last month he threatened to withhold federal aid from California for not implementing his ideas on forest management.

Newsom acknowledged that his state had not done enough to manage forests and that more than 100 years of fire suppression had allowed fuel to build up.

But he said global warming was driving fires and told Trump that 57 percent of forests in the state were under federal management and that only 3 percent of land in California was under state control.

"We've known each other too long, and as you suggest, (we have a) working relationship I value," Newsom told Trump. "We obviously feel very strongly that the hots are getting hotter. The dries are getting drier."

Newsom continued: "And so I think there's an area of at least commonality on vegetation, forest management. But please respect — and I know you do — the difference of opinion out here as it relates to this fundamental issue on the issue of climate change."

Trump, who has authorized federal disaster aid for California and Oregon, questioned that science.

Trump announced in 2017 that he would begin to pull the US out of the Paris Agreement on combatting global warming, while Biden says climate change is on his list of major crises facing the US.

"Talk to a firefighter if you think that climate change isn't real," said Democratic Los Angeles Mayor Eric Garcetti on CNN's State of the Unionon Sunday. "It seems like this administration are the last vestiges of the Flat Earth Society of this generation."

In 2018, a major scientific report issued by 13 federal agencies concluded that greenhouse gas emissions from burning fossil fuels could triple the frequency of severe fires across the US West and could reduce the US economy by as much as 10 percent off by the end of the century.

"We have to act as a nation," Biden said. "It shouldn't be so bad that millions of Americans live in the shadow of an orange sky, and they're left asking: 'Is doomsday here?'"

Trump lost California, Oregon and Washington — all Democratic strongholds — in the 2016 presidential election. Biden's running mate is US Senator Kamala Harris of California, who also served as the state's attorney general.

Reuters contributed to this story.