A Kelvin wave reaches the U.S.

One of the first major signs of this year's Super El Niño has reached the U.S. It's called a Kelvin wave, a deep ocean wave currently raising sea levels along the West Coast.

What is a Kelvin wave?

Kelvin waves develop along the equator during El Niño years when vast regions of Pacific Ocean water become much warmer than usual.

Not a visible wave

Kelvin waves are not massive waves that crash into shorelines during storms. Dillon Amaya, assistant professor of atmospheric sciences at North Carolina State University, says it's a planetary-scale wave that's not a wall of water…

“It's not a wall of water, it's not a tsunami, it's not a wave you can surf. It's a planetary-scale wave.”

Raising flood risk

Kelvin waves raise sea levels as they move up the coast, bringing elevated risk of floods and warmer water temperatures.

The October flooding in California

In early October, Southern California communities experienced a triple threat.Sea levels were already six to eight inches higher than normal because of the Kelvin wave.

“That storm surge was almost certainly made more devastating because of the Kelvin wave.”

Warmer water disrupts marine life

Kelvin waves bring warmer water up the coast, disrupting marine ecosystems.Tropical fish appear in unusual places, including a whale shark spotted off San Diego.

“We've seen tropical fishes in places that we don't normally see them. Like a whale shark was spotted off the coast of San Diego.”

More waves are coming

There are usually five to six Kelvin waves during a strong El Niño year. Dillon Amaya predicts the next Kelvin wave will reach San Diego in late October or early November, with several more expected…

El Niño expected to stay strong

Kelvin waves usually subside before the peak of El Niño.The El Niño pattern typically peaks late in the year or early January.NOAA researchers predict the El Niño will remain strong through early twenty twenty-seven.