In the most extensive study to date on sea level rise in California, researchers say damages by the end of the century could be far more devastating than the worst earthquakes and wildfires in state history.
A team of U.S. Geological Survey scientists concluded that even a modest amount of sea level rise—often dismissed as a creeping, slow-moving disaster—could overwhelm communities when a storm hits at the same time.
The study combines sea level rise and storms for the first time, as well as wave action, cliff erosion, beach loss and other coastal threats across California. These factors have been studied extensively but rarely together in the same model.
The results are sobering. More than half a million Californians and $150 billion in property are at risk of flooding along the coast by 2100—equivalent to 6 percent of the state’s GDP, the study found, and on par with Hurricane Katrina and some of the world’s costliest disasters. The number of people exposed is three times greater than previous models that considered only sea level rise.
And at a time when marshes are drowning, cliffs eroding, beaches disappearing and severe storms likely to become more frequent, scientists say even a small shift in sea level rise could launch a new range of extremes that Californians would have to confront every single year.
“It’s not just some nuisance that’s going to pop its head up once in a while,” said Patrick Barnard, research director of the USGS Climate Impacts and Coastal Processes Team and lead author of the study. “These are significant events that are going to recur and be 10 times the scale of the worst wildfires and earthquakes that we’ve experienced in modern California history.”