An 8-magnitude earthquake has hit off the coast of California, which displaces a massive amount of water that creates a tsunami.
Within five minutes of the quake, the giant wave is rushing toward the state’s coastline at speeds of up to 500 miles per hour that triggers a tsunami alert for an immediate evacuation.
About 30 minutes later, the tsunami floods coastal cities and does not subside for at least one-hour after, leaving a path of devastation in its wake.
While this was a simulated tsunami, residents along the California coast were minutes from experiencing it first hand Thursday.
A magnitude 7.0 quake struck about 55 miles off the shore of Eureka, rattling the region from San Francisco to southern Oregon, sparking a tsunami warning for more than five million residents.
Many got word to evacuate or move to higher ground, which Amy Palmer, Deputy Director of the California Governor’s Office of Emergency Services, said: ‘They did the right thing in this situation… it could have been devastation.’
The warning triggered widespread, panicked evacuations for about one hour before it was cancelled as experts confirmed that no tsunami had formed, despite the fact that the quake created the right conditions for one.
The California Geological Survey has created maps of tsunami hazard zones along the state’s coastline that residents can use to better understand their risk.
These hazard zones included Ventura, Oxnard and Malibu in the south, along with parts in the San Francisco Bay Area.
Scientists have warned that the major earthquake that rocked California on Thursday is a wake-up call to prepare for a future tsunami. State officials have mapped the areas most at risk
These maps were created based on an ‘extreme’ scenario in which a massive earthquake in Alaska sends a towering wall of water rushing toward the Golden State.
In Southern California, hazard zones include areas in or around Ventura, Oxnard, Malibu, Venice, Marina del Rey, Hermosa Beach, Redondo Beach, the ports of Los Angeles and Long Beach, Long Beach, Seal Beach, Sunset Beach, Huntington Beach and Newport Beach.
And in the San Francisco Bay Area, vulnerable locations include the westernmost areas in San Francisco’s Richmond and Sunset districts.
This also includes the Marina District, and areas along the Embarcadero, affecting a significant portion of the Financial District and South-of-Market areas.
If a tsunami were to hit the San Francisco Bay Area, experts have suggested that it would cause widespread devestation.
Communication systems would be down, hazardous chemicals would spill into the streets and infrastructure would be destroyed.
Tsunami warnings are rare for the West Coast, but much more common than they are for the rest of the country. This region is also overdue for a massive quake and resulting tsunami in the Cascadia Subduction Zone and/or the San Andreas fault.
Scientists refer to this inevitable event as ‘The Big One,’ as it would cause an estimated $200 billion in damage, 50,000 injuries and 1,800 deaths.
Officials issued a tsunami warning for more than five million residents, sounding off sirens and suspending service on the Bay Area’s commuter rail through its underwater Transbay tube
The threat of ‘The Big One’ is part of the reason why California officials are so vigilant about tsunami activity after a major earthquake.
Though the magnitude 7.0 quake was not large enough to be considered ‘The Big One,’ it was enough to produce a dangerous tsunami, Snider told the LA Times.
But because there’s no way to predict such an event accurately ahead of time, he and his team exercise an abundance of caution, especially when a quake hits near the coast, like Thursday’s did.
Though the potential tsunami never actually formed, the evacuation order was a reminder to California’s coastal communities that they always need to be prepared to flee in case one hits.
The last time officials issued a tsunami advisory for the West Coast was in January 2022, when an underwater volcano erupted in the South Pacific triggered a powerful tsunami.
The West Coast is so vulnerable to tsunamis because of its location on the Pacific Rim and its proximity to volatile fault lines, like the Cascadia and the San Andreas (STOCK)
By the time the wave reached the California coast, its impact was damaging, but not devastating. It flooded streets and a parking lot Santa Cruz Harbor, ‘where cars floated about like toy boats,’ the Los Angeles Times reported.
Floodwaters also poured into homes and damaged electrical infrastructure. Officials estimated the impacts totaled roughly $6 million in Santa Cruz alone.
The West Coast is so vulnerable to earthquakes and tsunamis because of its location on the Pacific Rim and its proximity to volatile fault lines, like the Cascadia and the San Andreas, according to the US Geological Survey.
The majority of tsunamis that hit the West Coast are teletsunami, or massive waves generated by seismic activity more that 1,000 miles away.
These distant tsunamis stem from large earthquakes generated around the Pacific Rim, also known as the ‘Ring of Fire’ because it is the most seismically and volcanically active area on Earth.
But tsunamis that hit the West Coast can also be triggered by nearby fault zones.
Because these rare events are almost impossible to predict, it’s important that residents have know the warning signs of a tsunami and have an emergency plan in place just in case one hits
The Cascadia Subduction Zone is a ‘megathrust’ fault that stretches over 600 miles from Northern Vancouver Island to Cape Mendocino California.
Megathrust faults form when two tectonic plates meet and one is forced beneath the other. The Cascadia Subduction Zone forms the boundary between the Juan de Fuca plate and the North American continent.
The San Andreas fault also forms the boundary between two tectonic plates, but it is not considered a megathrust fault because these plates tend to move horizontally past each other rather than one subducting beneath the other.
This fault spans more than 800 miles up and down the coast of California, from Cape Mendocino almost to the northern border of Mexico.
Both these faults are capable of producing enormous earthquakes.
The largest quake the that ever struck the Cascadia Subduction Zone happened in 1700. This magnitude 9.0 triggered a tsunami that swept across the Pacific Ocean and devastated the coast of Japan.
The San Andreas produced its largest earthquake on record in 1906. Scientists estimate is was a 7.9, and the violent shaking that struck San Francisco caused immense damage and claimed 3,000 lives, in part due to resulting fires.
Today, the West Coast is far better prepared for major earthquakes and tsunamis. Because these rare events are almost impossible to predict, states have designed infrastructure to withstand them, and have established warning systems and evacuation routes.
It’s important that residents have know the warning signs of a tsunami and have an emergency plan in place just in case one hits.
The warning signs include feeling a large earthquake, seeing a sudden rise or fall of the ocean or hearing a loud roar if you are by the coast.
The California Geological Survey says: ‘If you are on the beach or in a harbor and feel an earthquake, immediately move inland or go to high ground.’
‘If strong shaking lasts for 20 seconds or more, everyone within the tsunami evacuation area should evacuate as soon as it is safe to do so.’
