Two years have passed since a devastating earthquake and subsequent tsunami off the coast of Tohoku, Japan, caused massive loss of life and property. Since then, efforts to become more prepared for quakes and tsunamis have been ongoing throughout the world. In the U.S., the National Oceanic and Atmospheric Administration, or NOAA, along with state and federal agencies are partnering for Tsunami Preparedness Week from March 24 to 30. During the week, the NOAA encourages communities to become Tsunami ready.
Many would say that California is a place that needs a whole lot of tsunami prep. Only Alaska beats California as the state most likely to experience an earthquake, according to the United States Geological Survey. But for more than a quarter of a million people living in California’s coastal regions, the quake itself certainly wouldn’t be the only problem to worry about. Massive flooding from a huge tsunami could be a major part of the destruction, according to a new USGS study entitled “Community Exposure to Tsunami Hazards in California.”
The 60 page report, issued by the California Emergency Management Agency, reveals that tidal waves of eight meters (26 feet) or more could slam into northern California following an 8 magnitude earthquake, reports Agence France-Presse in The Raw Story. The study provides first responders, emergency planners and others with information about those who live in, work in and visit tsunami hazard areas in 20 counties and 94 cities along California’s coast, the USGS’s website explains, and includes maps that reveal the most vulnerable coastline areas, "from San Diego in the south to Los Angeles and Oakland," Agence France-Presse reports.
“The tragic loss of life and property damage associated with recent catastrophic tsunamis has raised global awareness of tsunami hazards, hazards,” the study notes, citing gigantic tsunamis in the Indian Ocean in 2004, off Somoa in 2009 and the particularly massive one that sprang off the coast of Japan two years ago.
Recent preparedness efforts, according to the USGS’s website, have included testing a tsunami-warning communications system, "table-top exercises" and public education forums and the production of educational materials.
As for the 2011 tsunami off of Japan, Crescent City, which is about 350 miles north of San Francisco, was among the worst-hit locations in California, with one death and boats flipped on top of one another, The Raw Story reports.
A tsunami generated by an earthquake far away, as in the Tohoku quake's case, poses relatively modest threat since waves are often smaller and there's more warning time, the website says.
But a much more severe tsunami could come from an earthquake at the Cascadia Subduction Zone (CSZ), a fault line that spans more than 620 miles, from northern California to Vancouver Island.
“A future CSZ-related earthquake (likely magnitude 8 or larger) would create a series of tsunami waves ... that would inundate these communities in 15 to 20 minutes after initial ground shaking,” the USGS report reveals. “Southern California communities would experience the Cascadia-related tsunamis in a far-field capacity, meaning they would not experience the ground shaking, and waves would arrive approximately one hour later.”