Last winter, atmospheric rivers drenched Southern California with record-breaking amounts of rain. Now, the same region is experiencing ravaging wildfires. By Thursday night, five major fires broke out across Los Angeles County, destroying thousands of buildings and causing mass evacuations.
Inconsistent weather patterns are part of why the wildfires are spreading so easily, according to a study published Thursday by Nature Reviews. Lead researcher of the study Daniel Swain, a climate scientist at UCLA, explained sudden shifts between extremely dry and wet weather, known as hydroclimate whiplash, create the ideal conditions for wildfires.
“The worst climate for wildfire is not one that gets perennially drier,” Swain said to National Geographic in September 2024. “If you alternate getting wetter and dryer, while it’s getting hotter, you have enough water in the system at least every few years to regrow everything and then burn it off again.”
Following an anomalously wet winter at the start of 2024, Southern California swept into months of near drought. Since May 5, when Los Angeles recorded 0.13 inches of rainfall, the amount of measurable rain the city has received is negligible.
“We’re in a whiplash event now, wet to dry, in Southern California,” Swain told the L.A. Times in a Jan. 9 story. “The evidence shows that hydroclimate whiplash has already increased due to global warming, and further warming will bring about even larger increases.”
Swain’s group of researchers found a link between climate change and the increase of hydroclimate whiplash. As the Earth becomes warmer, the atmosphere’s capacity to absorb, release, and evaporate water increases exponentially — what the scientists call an expanding atmospheric sponge.
With climate change continuing to exacerbate natural disasters, scientists urge people to educate themselves about the impact of anthropogenic activity.
“Larger and more severe wildfires are one of the most obvious manifestations of a planet that is heating up,” said Jennifer Marlon, an environmental research scientist at Yale, to the New York Times. “If we can help people better understand that connection, we may be able to build support for working more quickly to reduce the root causes of the problem — burning fossil fuels.”
