An 8.7-magnitude earthquake struck off Russia’s Kamchatka Peninsula on July 29, lighting up tsunami alerts for the entire U.S. West Coast.
San Francisco is no stranger to earthquakes. As we learned in real-time last year, the San Francisco Bay Area is far from impervious to tsunamis (and the chaos that can ensue when warning alerts go off due to their threats), as well. At least 71 tsunamis have been recorded in San Francisco Bay since geological recordings began for the region around 1854.
On Tuesday, July 29th, an 8.7M tremor — about a once-a-decade earthquake — could add another to that list.
The U.S. Geological Survey (USGS) said in its most recent assessment that an 8.7-magnitude earthquake shook off the Kamchatka Peninsula; peninsulas, too, have a higher propensity for creating and intensifying tsunamis, due to their ability to displace coastal waters by way of both seismic force and land collapse.
“This is a significant, real event,” says Reid Wolcott, a meteorologist with the weather service in Seattle. The USGS has estimated the 8.7M quake occurred about 85 miles off the east coast of the aforementioned Kamchatka Peninsula with a depth of nearly 12 miles.
Thankfully, the area it struck off of is not densely populated, nor does it have close proximity to heavily populated coastal regions. (For context, the 2004 Christmas Day tsunami — a series of waves that collectively caused $10 billion in damages and claimed over 225,000 lives — was caused by the 9.1M earthquake and, because of its epicenter’s closeness to densely populated coastal communities, remains the deadliest tsunami in history.)
“The imminent threat is for Alaska and areas near the quake,” Wolcott continues. “The National Tsunami Warning Center needs additional observation information before more is known about the threat to the US West Coast.”
As of publishing, the entire West Coast, including the entirety of Alaska and Hawaii, is under either a tsunami warning or a tsunami watch. In the likely case the quake did produce a tsunami — multiple government branches, international and otherwise, are currently investigating the potential size of the wave; estimates from Japan’s meteorological agency warn of a wave at least 3 feet high will reach the north islands and generate flood conditions for coastal communities — the wave is expected to be small, thanks to the remoteness of the initial quake.
For us in San Francisco, if a tsunami were generated with enough energy to reach the SF Bay Area, we should expect the wave just after midnight, around 12:15 a.m. July 30th, and Los Angeles would then see a wave around 1 a.m.
The National Weather Service is still investigating the imminent threat and will update the public with its findings and any precautionary measures the agency deems necessary. If we do, in fact, see a big ol’ wave, may we all press the Macy’s Cheescake Factory to stay open late for a rooftop viewing.
