This quick cycling between very wet and very dry periods — one example of what scientists have come to call “weather whiplash” — creates prime conditions for wildfires: The rain encourages an abundance of brush and grass, and once all that vegetation dries out, it only takes a spark and a gust of wind to fuel a deadly fire. That’s what happened in Los Angeles County this week, when a fierce windstorm fueled the Palisades and Eaton fires, which as of Wednesday night had killed at least five people, destroyed more than 2,000 buildings, and forced tens of thousands of people to evacuate their homes.

The kind of weather whiplash that fueled the fires is only becoming more common, and not just in the United States. A new analysis in the peer-reviewed academic journal Nature Reviews Earth & Environment has found that rapid shifts between heavy rain and drought (and vice versa) are becoming more intense — and the trend is unfolding faster than climate models have projected. Across the world’s land area, weather whiplash within three-month periods has increased by 31 to 66 percent since the mid-20th century, according to the research. That means that most places around the world find themselves getting both wetter and drier in quick succession, a dangerous combination that can lead to landslides, crop losses, and even the spread of diseases.