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How a “super El Niño” could create record-breaking warming

El Niño is coming. And its impacts may last far longer than it does.

This story was originally published by Inside Climate News and is reproduced here as part of the Climate Desk collaboration.

The Pacific Ocean is a giant climate cauldron, with a powerful heat engine that affects storms, fisheries, and rainfall patterns half a world away, and scientists are watching closely to see if it’s about to boil over.

Their projections suggest the tropical Pacific is simmering toward a strong El Niño, the warm phase of an ocean-atmosphere cycle that can intensify and shift those impacts.

In a world already superheated by greenhouse gases, a strong El Niño during the next 12 to 18 months could permanently push the planet’s average annual temperature past the 1.5 degrees Celsius warming threshold enshrined in scientific documents and political agreements as a turning point for potentially irreversible climate impacts.

The Western US is already rationing water — and summer is still months away

Climate scientists also recently published a study showing that strong El Niño events can trigger what they called “climate regime shifts,” meaning abrupt, lasting changes in heat, rainfall, and drought patterns.

El Niño is one of the planet’s biggest natural release valves for ocean heat. The venting starts with periodic shifts of swirling ocean currents and winds over the Pacific. That causes huge stores of tropical ocean heat to surge eastward from the Western Pacific Warm Pool, roughly between Australia and Indonesia, northward to Japan. Those tropical seas are by far the warmest ocean region on Earth, and span an area four times as large as the continental United States.

When that ocean heat spreads across the equatorial Pacific, it spills into the atmosphere in pulses that tilt weather patterns, reroute powerful high-elevation winds, raise global temperatures, bleach coral reefs, and disrupt fisheries and ocean ecosystems. The effects hit continents as well,........

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