Experts warn strong El Niño could bring record sea levels to California coast with flooding concerns
SAN FRANCISCO -- Experts are warning that a strengthening El Niño could trigger coastal flooding, beach erosion and some of the highest sea levels ever recorded along the California coast in the coming months.
Climate scientist Daniel Swain said that warming in the tropical eastern Pacific Ocean is already underway and evolving rapidly.
"Just looking at the maps, even this week, things are changing very quickly now in recent days," Swain said.
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Swain said the current El Niño is expected to intensify significantly.
"Is expected to strengthen considerably from here. Strengthening ultimately to a very strong or so-called Super El Niño. That's what that term means, it's a tier higher than strong, it's very strong, and could even become potentially the strongest on record," Swain said.
Thousands of North Bay residents joined a virtual town hall Tuesday night to discuss the potential impacts. Months after powerful king tides flooded neighborhoods, residents are worried about it happening again.
"Likely the highest sea levels ever recorded on the California coast associated with this event," said Mark Merrifield of the Scripps Institution of Oceanography.
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According to the experts, water levels in San Francisco Bay rose significantly during the 2023-24 El Niño and king tides, and the current system appears stronger.
More than 5,700 people watched the virtual town hall, which was led by State Sen. Mike McGuire. Much of the discussion focused on what California could experience later this year and into early next year.
"But the big impacts will probably not arrive for a couple of months, later in the fall into winter," Swain said.
Experts said the most significant impacts could occur around late December, January, February or March.
Swain said coastal flooding is likely to be the biggest concern. Higher sea levels and larger waves could also contribute to beach erosion and cliff failures.
"Those are going to cause the beaches of California to erode and narrow, it's well documented that during El Niño events beaches across the entire state tend to move landward by about 30 meters or so," Merrifield said.
Swain also noted that many California homeowners do not carry flood insurance and said residents in high-risk areas may want to consider obtaining coverage.
Experts emphasized that the forecasts are based on current weather models and remain predictions subject to change as conditions develop.
