Sea surface temperatures in the Pacific Ocean have broken a new record, climate scientists say. This is yet another signal that this year will see an exceptionally strong El Niño.
El Niño is a cyclic climate pattern that influences weather around the globe. It typically brings heavy rains to the southern U.S., for instance, and dry conditions to other parts of the country, such as in the Pacific Northwest.
Researchers determine an El Niño year by analyzing ocean temperatures in a specific part of the equatorial Pacific that serves as a bellwether for extreme weather conditions to come. And now, climate scientists say, this region is incredibly, unusually warm—much more so than it’s ever been since we started keeping track more than a century ago.
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Sea surface temperatures in this region are 3.05 degrees Celsius (5.49 degrees Fahrenheit) warmer than usual, the highest anomaly seen since 2015, in which such temperatures were 3.02 degrees C (5.44 degrees F) above normal, noted climate specialist Jeff Berardelli in a social media post.
Kim Wood, an associate professor of hydrology and atmospheric sciences at the University of Arizona, said in a social media post that the region’s sea surface temperatures have been “unparalleled” for this time of year “for a while.” Based on a measurement that accounts for background warming of ocean temperatures as a result of climate change, this year’s El Niño hasn’t yet hit an all-time high, but it is hotter than it’s ever been for late September.
No matter how you slice it, the new record is a sign of what experts say will be a brutal El Niño. “This is probably going to be the superlative El Niño event of our lives so far,” says Daniel Swain, a climate scientist at the University of California Agriculture and Natural Resources (UCANR).
That’s bad news for an already warming planet. As Scientific American previously reported, El Niño events typically raise global temperatures, which puts this year, as well as 2027, at risk of being among the hottest years ever recorded.
Additional reporting by Andrea Thompson.
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