California Coast Prepares for Significant Sea Level Surge Due to Kelvin Wave

California’s coast is preparing for a surge that could raise sea levels by as much as one foot in the coming days, increasing the risk of flooding and erosion. This surge, referred to as a 'coastal trapped wave' or 'Kelvin wave,' is a phenomenon associated with El Niño and has been developing along the California coast in recent weeks. The Kelvin wave is a large, sustained bulge of water that will elevate ocean levels across an area extending 12 to 18 miles offshore, potentially impacting California’s coastline significantly. This surge follows a series of unusual ocean events that have already affected coastal communities, including waves that overtopped the Pacific Coast Highway in Malibu last month. With California currently experiencing a series of storms, the elevated sea levels could exacerbate flooding and erosion issues. Dillon Amaya, an oceanographer at North Carolina State University, noted that every two to four inches of sea level rise effectively doubles the flood risk. While Kelvin waves are common, the current situation is particularly concerning due to the combination of this wave with other ongoing coastal challenges. Mark Merrifield, director of the Center for Climate Change Impacts and Adaptation at the Scripps Institute of Oceanography in La Jolla, stated that California may soon experience its highest recorded sea levels. Sea temperatures are already elevated, and several Southern California beaches are facing erosion while recovering from recent hurricanes. Amaya explained that the Kelvin wave is both a cause and a symptom of El Niño, as it suppresses the cold water that typically rises from the ocean depths, contributing to warmer surface temperatures characteristic of El Niño.