California Drought, Marine Heat More Likely With Warming

A persistent wash of warm waters off the West Coast, which caused wildlife die-offs and blocked drought-quenching storms from reaching California last year, was caused by the happenstance interplay of natural ocean cycles, research findings published Monday show.

The findings also suggested that while the drought and the blob of warm water were the result of the natural whims of the weather, climate change could make such events more likely and intense in the future. To a small extent, it’s already doing so.

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The warm water was the result of an atmospheric accomplice that helped to parch the West: a ridge of high pressure. The timing was unfortunate. Experts had expected one of the most powerful El Niños on record last year to douse California’s drought, but the high pressure system off southern California deflected its hearty storms northward.

With El Niño now over, California is stuck in its fifth year of drought, with the most severe conditions in the south, where the ridge’s effects were strongest