​​Strongest El Niño in 140 years? This one could actually deliver for California

Rare cluster of three tropical cyclones It will pass either side of the equator in the western Pacific this week, creating what one scientist has called potentially the strongest burst of westerly winds over the equatorial Pacific in the last century. The eruption pushes warm water eastward at a critical moment and has “real potential for the strongest El Niño event in 140 years,” said Paul Roundy, an atmospheric scientist at the University at Albany.

The European Center for Medium-Range Weather Forecasts’ recently released seasonal forecast for April shows that nearly all of its models expect the world to reach El Niño conditions by mid-June. By October, nearly half of sea surface temperature anomalies exceed 2.5 degrees Celsius above average.

A strong El Niño will likely significantly reshape global weather patterns, potentially pushing global temperatures to record levels in 2027.

Tropical cyclones are just the latest evidence of an emerging El Niño that will potentially reach record levels. Their combined circulation is fueling the westerly wind burst and is now pushing warm water eastward across the Pacific. This eruption “lies west of the hottest water in the Pacific Ocean right now, so it’s in an ideal position to direct that warm water eastward to create a strong El Niño event,” Roundy said. He predicted that the setup could cause El Niño to arrive quickly within one to two months.

This is the end series of strong wind bursts from the west These waters, which have been sweeping the equatorial Pacific since January, put an end to the La Niña pattern and spread unusually warm water both at the surface and at depth across the Pacific. Each successive eruption has pushed hot water further east, and this eruption, fueled by a rare triple hurricane pattern, may be the strongest yet.

“What’s different this year is not a single model, but the level of agreement between multiple models,” said Muhammad Azhar Ehsan, a climate scientist at Columbia University’s International Research Institute on Climate and Society. He noted that forecasters from Australia and NASA, as well as Europe, “are pointing to a strong El Niño.” The next official forecast from the research institute on April 19 is expected to be stronger than: last month’s viewEhsan said.

The National Oceanic and Atmospheric Administration is scheduled to release its updated forecasts for El Niño on Thursday.

Although El Niño is thought to bring more rain to California, there are reasons why residents are greeting this news with some uncertainty. In 2015, forecasters warned that a “Godzilla El Niño” would emerge, raising hopes that it would end. devastating multi-year drought It led to reservoirs being depleted and communities becoming water rationed. A strong El Niño arrived, but the drought-preventing rains did not arrive. While the Bay Area finished the winter with roughly average precipitation, Southern California was only 72 percent below normal. This was a reminder that not all El Niño events occur as expected.

A parallel in 1997

Roundy said the unfolding event follows an evolution “similar to 1997,” when warming occurred in the eastern tropical Pacific near the coast of South America. This is the pattern associated with strong El Niño events that translate into above-normal precipitation in California. During the 1982-83 El Niño years, storms destroyed 33 oceanfront homes, damaged thousands more, and caused hundreds of millions in damage in 46 counties where disasters were declared. The 1997-98 El Niño winter brought twice-normal precipitation to much of the state, causing 17 deaths and nearly $850 million in damage from the storm.

In contrast, the 2015–16 event first developed in the Central Pacific; It’s a model that, as Roundy explains, “promotes heavy precipitation off the coast of California rather than in California.”

Daniel Cayan, a climate researcher at Scripps Institution of Oceanography who has studied California’s hydroclimate for decades, said he sees reasons for cautious optimism about water supplies in California and the Western U.S. next year.

“I’m counting on a strong El Niño,” Cayan said. “It looks promising for a pretty strong event that will probably continue into the winter of 26-27.”

If the eastern tropical Pacific stays warm into winter, California will likely see a storm track pattern that directs Pacific storms directly into the state, Cayan said.

“Hopefully this means the extremely dry southwest will enjoy renewed moisture,” Cayan said. But he added: ‘It’s still early.’

Cayan cautiously softened her perspective. “All of these are precautionary measures against the danger of being injured and battered due to previous (experiences),” he said.

Roundy made a similar point. Although the event looks more like 1997 than 2015, “I cannot rule out the possibility that (sea surface temperature) patterns during the rainy season in California are more similar to 2015,” he said.

One of the signals to watch is the temperatures this summer and autumn. Cayan noted that during previous strong Eastern Pacific El Niño events, temperatures in the West were colder than average from summer to winter. If this pattern begins to emerge this summer, it could be a sign that the event is following the 1997 playbook.

But Cayan cautioned that each event has its own characteristics, and today’s much warmer ocean bottom means historical patterns cannot be clearly repeated.

By mid-summer the picture will become significantly clearer. For now, the ingredients for a historical event are ready.

This article was first published at: Strongest El Nino in 140 years? This can actually deliver to California.