How climate change made deadly floods in Spain even worse
In 2024 extreme rain and floods hit the Spanish region of Valencia, killing more than 230 people in the country. Now a new study shows climate change made it even worse
Locals and volunteers are seen manually cleaning up the streets filled with mud with shovels and other tools after flooding in the region of Valencia in Spain in late 2024.
In October 2024 the Spanish region of Valencia was smothered in a downpour of biblical proportions. In just a few short hours, more rain fell on the region than would in an average year. The precipitation triggered a string of flash floods that swept away bridges and cars and even derailed a train. More than 230 people in Spain were killed in the deluge. At the time, scientists speculated that climate change had fueled the event—and now a new study reveals how much it did so.
The study shows that, because of climate change, the rate of intense rainfall was about 21 percent higher over a six-hour period in Valencia than it would have been without the influence of climate change.
The research is what’s known as a climate attribution study: the science is clear that a changing climate will, in general, make extreme weather and disasters such as floods and wildfires both worse and more frequent. But it can be difficult to say exactly how much global warming influenced a specific event.
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In the new study, the researchers used real-life data to simulate different flooding scenarios and compared them to measurements of what the climate looked like before the widespread use of fossil fuels in the new study. By doing so, the researchers were able to determine not only that the rainfall in Valencia was more intense because of climate change but also that the deluge was more widespread thanks to global warming.
The area that received about seven inches or more of rain in 24 hours during the disaster was an estimated 55 percent larger than the region that would have received that amount under preindustrial conditions, the researchers found. Notably, 2024 was the hottest year on record.
The study was published on Tuesday in the journal Nature Communications.
The findings show that the kinds of storms researchers once predicted would happen thanks to climate change are “already becoming evident,” the authors write. Ultimately, they highlight an “immediate need” to ensure cities are prepared for a possible onslaught of extreme weather as a result of climate change.
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