New tsunami hazard maps highlight threat facing seven California counties — even Napa Valley — as climate change-linked sea level rise threatens coastal homes and businesses.
A new map shows the danger of a major earthquake as Southern California residents prepare to confront a potential threat that was not anticipated when the area was devastated by a series of devastating quakes last year.
“If you really look at the map, you can see where this could be,” said Tim Hagerty, an associate coastal geologist at the U.S. Geological Survey. “The most likely area is up the Ventura and Santa Barbara county line, and it could be up into Orange County.”
A large-scale earthquake is projected on the coastal areas of the coast from southern Orange County to the Ventura County line and even into Santa Barbara County, according to a new report issued jointly by the U.S. Geological Survey, the U.S. National Geodetic Survey and the U.S. Nuclear Regulatory Commission.
A series of small quakes, the latest on Tuesday, was the latest warning sign for residents in Southern California. They have been preparing for three years to deal with the possibility of the kind of magnitude-8.0 earthquake that devastated areas of Southern California, and the latest quake could have even greater impacts because it would likely be “forecast” rather than just triggered.
But experts now say that it’s too early to talk about a tsunami that could wash away everything in a radius of a mile or so.
Hagerty said it would be “a huge, huge tremor,” but it’s not a tsunami.
“A tsunami is a wave, that sort of thing,” he said.
A tsunami is defined by the U.S. Coast Guard as a wave with a height at least six stories and a wavelength no greater than a thousand miles and rising above ground level “for at least 7 seconds” while traveling faster than 2.5 mph in water.