Kelvin Wave Expected to Raise California Sea Levels by Up to One Foot
Scientists warn that a large Kelvin wave of warm Pacific water, intensified by a strong El Niño, could lift California's sea level by as much as a foot for several months.
A massive Kelvin wave— a long, slow-moving bulge of warm water that travels along the equator— is forecast to reach California within days, potentially raising local sea levels by up to one foot for months, according to scientists cited by the Guardian. The phenomenon is driven by weakened or reversed trade winds that allow a thick layer of warm water in the western Pacific to move eastward toward the Americas. Researchers from NASA and the National Oceanic and Atmospheric Administration note that this natural process coincides with a century-long background sea-level rise of about eight inches and an unusually strong El Niño event.
State officials are preparing for higher tides expected around Thanksgiving and Christmas, as well as the possibility of El Niño-related storms. Governor Gavin Newsom has declared a state of emergency, and coastal regulators are advising homeowners to inspect drainage systems and reinforce properties vulnerable to flooding.
NOAA researcher Andrew Leising told the Orange County Register that Kelvin waves are a regular occurrence, adding that multiple smaller pulses have already reached Southern California. "They always happen—it just depends on what else is going on whether we pay attention or not," he said.