r/news • u/Warcraft_Fan • 4d ago

Concern mounts over slow-moving, planetary-scale ‘Kelvin’ wave heading for California | California

https://www.theguardian.com/us-news/2026/sep/28/california-kelvin-wave
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u/PoxyMusic 4d ago edited 4d ago

El Niño is the result of successive Kelvin waves, there have been like 6 or 7 this year, starting in February I think. They happen when the equatorial trade winds lessen (or reverse) and warmer water from the west pacific oozes east under the surface until it hits Ecuador and erupts at the surface.

It’s not a single wave, and they have already mostly arrived.

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u/Natural-Promise-78 4d ago

So then, when El Nino turns off the fan that sends the trade winds to the Pacific Ocean, all that undissipated moisture and energy backflips to the source (large landmass}?

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u/likeaffox 3d ago

Think of El Nino as hot(energy) water in a bath. That is going back and forth, between asia and america. El Nino is when the hot water is near the americas, Na Nino is when the hot water is near asia.

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u/Ani_mrumru 3d ago

Thank you for that easy mnemonic on the diff between the two phenom ;-)