As Los Angeles reels from the damage of last weeks fires, some people have argued that the city didnt do enough to prepare. But critics talking about water supplies are ignoring the real problem: climate change.Climate change is driving hydroclimate whiplash, wild swings between wet and dry weather. After years of drought, L.A. saw record-breaking rain in 2022 and 2023. Then came drought: For eight months, the city has seen almost no rain. The extra-rainy years make more grass and vegetation growand when it later dries out, there becomes extra fuel for a fire.As the planet heats up, the atmospheric sponge is growingthe atmosphere is sucking more water out of plants and soil, making it even drier than it would be with drought alone. When it later rains, the atmosphere is holding more moisture, so it dumps more precipitation.If theres heavy rain after a fire burns away vegetation, theres a greater risk of landslides. If theres finally a major storm later this winter, all of these very steep, recently burned slopes immediately in populated areas could pose big problems, says Daniel Swain, a climate scientist at UCLA who published a new paper about the global growth of hydroclimate whiplash. Thats a hazard that I can already anticipate, he says. Communities, even as theyre dealing with some parts of the community still being on fire, probably need to be grappling with that because it could be as little as a week or two before the next thing hits.Since the middle of the 20th century, the new paper says, hydroclimate whiplash has grown globally by between 31% and 66%.When the fires started after L.A.s own weather whiplash, the conditions were a worst-case scenario, with extremely dry vegetation and extremely strong winds. The first night, the winds were so strong that firefighting planes couldnt fly. On the ground, firefighters were also limited in what they could do. Critics have pointed to the fact that some fire hydrants ran out of water, but thats a red herring.I think what people are forgetting is there were literally hundreds of fire trucks all drawing upon the same water mains, Swain says. You can only push so much water through city water pipes per unit time. (As houses burned and pipes in homes were broken, that also affected water pressure.) Even if the city had backup water supplies, he says, it would have been unlikely to make much of a difference given the extreme conditions.Thats not to say that society cant do more to preparebut its not a matter of having more fire trucks or water. First, homes can be made more resilient to fire. Many of the houses that burned caught fire inside after embers blew through vents; replacing vents with a version that blocks embers is a simple change that could have saved some homes. Most Californians also still havent fully embraced the idea of defensible space around a homemaking sure that trees and other vegetation arent too close, and replacing flammable structures like wood decks. Relatively simple changes could make a difference, and the fewer homes that burn, the less a fire can spread. (Cities might eventually also have to take the more complicated step of deciding that some areas arent safe to live in, and change zoning.)Still, in the most extreme-fire weather, theres only so much that can be done. In the L.A. fires, changes might have lessened the damage, but probably couldnt have ever eliminated it. Its also critical to focus on cutting emissions because hydroclimate whiplash is projected to get significantly worse as the planet keeps heating up. Swains study found that if we hit 3 degrees of warming, whiplash will more than double: This is actually a very good illustration of why each fraction of a degree of warming matters and shaving off each fraction of a degree is really important, he says.