Wildfires ravaged the Western United States this year, with some of the biggest fires in California and Oregon history burning through tens of thousands of acres.
Now there's new scientific research showing human-caused climate change is driving the increase in wildfires.
A UCLA professor used artificial intelligence to study wildfire data, focusing on vapor pressure deficit.
VPD is a measurement of how much moisture the air can hold. The higher the VPD level, the more water vapor air can pull out of plants and the soil, leaving behind dried-out fuel for wildfires.
Rural areas like forests have higher VPD levels.
The study of 40 years of data shows the majority of vapor pressure deficit contributing to this dryness is created by human-caused global warming.
It's not all because of people. Natural changes in the climate also impact the amount of moisture that can be absorbed into the air.
Residents in fire-prone states like Colorado are surprised they are still dealing with the blazes this late in the year.
"I definitely panicked a little. I never thought at this time in the year a fire, especially that close to my home, would be such a problem. My family, we just started getting ready, we got ready to pack up and then about an hour later we had to leave," said Estes Park, Colorado, resident Alec Throne.
The scientists predict as the climate continues to change, the VPD levels will grow, creating more fuel — and driving even larger wildfires.