New maps from the California Geological Survey show that possible tsunamis make flooding more likely in Alameda, Monterey, and San Mateo counties, as well as other coastal places that have been identified as at risk in previous studies.
The California Department of Conservation says that the new maps, which came out to align with California’s Tsunami Preparedness Week, which starts March 22, use new data and better computer modeling to show how far inland a surge of seawater might go in the worst case.
After the Tohoku-Oki earthquake and tsunami in Japan in 2011, which killed about 15,000 people and did a lot of damage, including to the Fukushima Nuclear Power Plant, the government started to update California’s tsunami danger maps.
“Japan planned using data from several hundred years of tsunami records, which made sense,” said Steve Bohlen, Acting State Geologist of California and head of CGS. “Then they were hit by a once-every-million years tsunami.” “So, we’re using a thousand-year scenario as the baseline for our new maps, hoping to avoid the tragic loss of life experienced there.”
Here is what you need to know about the California tsunami records that were just released.
What new places were added to the Tsunami Hazard Maps for California?
The California Geological Survey found that another big earthquake in the Aleutian Islands in the northern Pacific Ocean would be the biggest threat to many parts of California from tsunamis.
Rick Wilson, who runs the CGS Tsunami Program, said, “These maps are based on the best data we have, but there’s a margin of error when you’re trying to think about something that happens once every thousand years, so we err on the side of caution.” “The buffer zones on the maps take that into account.” We worked closely with local emergency planners to find places where the mapped tsunami risks have changed. This way, they can make changes to their escape plans.
When the study was done, it was thought about what might happen if a big earthquake and tsunami hit the eastern Aleutian Islands:
