When President Donald Trump visited the piles of ash and charred rubble of what used to be Paradise, Calif., this month, he said that the Camp Fire was a “really, really bad one.”

“We’ve never seen anything like this in California,” he said. “It’s total devastation.”

Reporters asked the president whether seeing what remained of the northern California town and walking among the ashes of the dead made him rethink his opinion on climate change — that it is a hoax, fake news or simply nonexistent.

“No,” Trump answered. Instead, he placed blame squarely on California forest management.

But according to the National Climate Assessment released less than a week after Trump visited the fire-stricken state, climate change is making wildfires worse and more common.

Wildfires killed nearly 100 people so far this year in California. The majority of those fatalities occurred in the Camp Fire that consumed the city of Paradise in early November. The disaster left little to be recognized, not even teeth or bones to identify victims. Around 200 people are still missing since the flames exploded Nov. 8, the Los Angeles Times reported Monday, but search teams are finding it nearly impossible to recover remains.

Scientists have been clear that rising temperatures and decreasing humidity will lead to more destructive wildfires. Here’s what they know, according to the climate change report released by Trump’s administration late last week.

Climate change is real and caused by humans.

Earth’s climate is “changing rapidly,” much faster than it has changed throughout history. Global temperature has increased nearly 2 degrees Fahrenheit since the industrial era, and human activity, mainly fossil fuel burning, is to blame. The impacts are far-reaching, from things like sea level rise to loss of biodiversity — and more intense wildfires.

Climate change has already made fires worse.

A 2016 study found that without climate change, wildfires in the United States would be significantly less destructive. Fires have consumed more acreage because of climate change, the study shows. As of 2015, researchers estimate that “the area burned by wildfire across the western United States over that period was twice what would have burned had climate change not occurred.”

Wildfires will be more destructive in the future.

Extreme Santa Ana wind events are more common now than they were in 1950. These very dry winds, named for the mountain range in southern California, flow from east to west during fall and winter. As they travel from mountains to ocean they sink, causing air temperature to rise and humidity to plummet. They are a perfect tinderbox for wildfires, and scientists say they are happening more often.

If greenhouse gas emissions continue unrestricted, wildfire frequency in the West could increase 25 percent, and the number of the largest fires — those bigger than approximately 12,000 acres — will triple. Greenhouse gases increase temperatures and heat dries out vegetation, even in non-drought years. Dry brush and grass is the main fuel for wildfires, once they ignite.

Climate change could be making fires harder to control.

The people who confront these infernos say the worst wildfires behave differently now than they did in the past, driven across the landscape by extreme Santa Ana winds. For decades, PBS Newshour reported, officials depended on the laws of thermodynamics to fight fires: They spread uphill because heat rises, so fight them from downhill.

That principle didn’t hold true this year. Firsthand video of harrowing evacuations through burning neighborhoods suggest that recent fires are spreading faster than people can evacuate. The Camp Fire ignited Nov. 8, around 6 a.m., and by late afternoon Cal Fire reported that it had consumed 8,000 acres. Unable to create downhill perimeters fast enough, officials battling the Carr Fire in July said they turned their attention to helping people outrun it. People fled downhill in the Camp Fire, too, with flames at their heels.

Research shows that climate change is making California’s wildfires worse. If it continues unabated, scientists say, disasters like the Camp Fire will happen again.