The rising sea levels pose a significant threat to California's coastal communities, increasing the risk of flooding, beach erosion, and damage to homes and infrastructure. High tides and storm surges could amplify these effects, as seen in recent incidents where homes in Southern California were battered by hurricane swells. Marine ecosystems are also at risk, with harmful algal blooms already being observed. The ongoing marine heatwave, unrelated to El Niño, further stresses the region's marine life. Experts caution that the combined impact of these factors could lead to one of the most severe coastal challenges in recent history.