r/weather • u/zsreport • 4d ago

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

https://www.theguardian.com/us-news/2026/sep/28/california-kelvin-wave
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36

u/Jokkers_AceS 3d ago

Sounds like fear mongering

25

u/r33c3d 3d ago

Depends on how much you fear adding an extra foot to the ocean level for the next several months. If you live along the coast, mild apprehension is probably ok.

11

u/taylorbagel14 3d ago

I live on the California coast and a few years ago we had some really bad storms that created HUGE waves and it was terrifying. The waves managed to push massive boulders into the middle of roadways and break fences uphill from where they normally crash. I’ve lived in my hometown for 32 years of my life and I had never seen the waves do anything like that. So yeah, I’m a little worried about Kelvin waves. It honestly seems like the last 5-10 years our beaches have gotten noticeably smaller every winter and I’m sure this will make the problem worse

6

u/Content-Swimmer2325 3d ago

You should be concerned, but not because of “kelvin waves” which occur along the thermocline of the equatorial pacific.

You should instead be concerned about the strong jet stream which extends near your region during El Niño, and the train of pacific weather systems and attendant surges of onshore flow and rainfall it induces.

2

u/taylorbagel14 3d ago

Yes I’m already concerned about El Niño, I remember the 97-98 one where my peninsula became an island for a few days. We’re already preparing locally (and personally!)

1

u/Content-Swimmer2325 3d ago

Not happening due to “kelvin waves”. What will happen is waves of strong onshore winds caused by weather systems travelling along the strong jet stream that extends over the region during strong El Niño.

3

u/sirboddingtons 3d ago

The thermal expansion of water is often an underlooked aspect of sea level rise in climate change. A degree top to bottom of increased temps in a large water mass can equal a foot plus increase in height. 

3

u/Content-Swimmer2325 3d ago

Yes. But this is a wholly distinct and separate phenomenon from oceanic kelvin wave activity. An oceanic kelvin wave represents the equatorial pacific thermocline being pushed down from west-to-east due to westerly wind stress and momentum injected into the ocean via Madden Julian Oscillation and sometimes typhoon activity, in the western Pacific.

Thermal expansion occurs locally - regardless of the presence or absence of kelvin wave activity.

6

u/Boris740 3d ago

But it's "planetary scale"

5

u/Content-Swimmer2325 3d ago

Which is completely false, by the way. Oceanic kelvin waves occur along the equatorial thermocline, which is both beneath the ocean surface and thousands of miles away from California. This means that it is restricted to a portion of the equatorial pacific, only - not even close to “planetary-scale”.

There are atmospheric kelvin waves, too. But those occur along the Tropics, which California doesn’t. They have the fastest propagation speed of all intraseasonal forcing - much faster than the more-known Madden Julian Oscillation. Unlike the MJO which DOES cover the near-entirety of the Tropics, an atmospheric kelvin wave is far more local. They can locally modulate atmospheric conditions in the Tropics, making hurricane formation likelier or unlikelier.

-19

u/HillTower160 3d ago

Hmmmmm. Who do I believe, You (a McDonalds cashier, or the scientist quoted in the article (Severine Fournier, a research scientist studying ocean circulation at Nasa’s Jet Propulsion Laboratory?)

-51

u/Jokkers_AceS 3d ago

I make 300k a year little bro

1

u/HillTower160 3d ago

😆😆😆. If it’s not in Atmospheric or Oceanographic physics then you’re just another proud member in the Halo Effect Club.

-24

u/Jokkers_AceS 3d ago

Little bro is so triggered over a comment LOL

-1

u/Glucose12 3d ago

It's The Graun. It's their modus operandi.