California Earthquake Tsunami Warning: Report on the Latest Warning

On Thursday, 4th December 2024, an earthquake occurred offshore over 200 miles of Northern California. Five minutes after the quake struck the region, millions of Californians received a California earthquake tsunami warning on their cell phones.

This tsunami alert caused a panic response from the citizens living on the Californian coastline. However, the authority canceled the warning about an hour after the tsunami broadcast alert. Why did the authority cancel it? Below is the brief report on the latest tsunami California warning.

About the 4th December California Earthquake Tsunami Warning 

A quake with 7.0 magnitude occurred offshore near Ferndale, CA 4th December. This earthquake caused the National Tsunami Warning Center to issue a warning. The authority broadcasted this alert at 10.49 local time, 5 minutes after the earthquake.

Reports said more than five million cell phone users received the warning message. They mostly live on the coastline of California, from Oregon to Santa Cruz. 

In addition, A number of cell phone users living several miles inland also get this alerting message. The message told them they were in danger and must get out of the beach and move to a higher ground. 

Why Did Authorities Cancel the Warning?

Why is the California earthquake tsunami warning canceled? This cancelation is due to the evaluation done by the authority.

The earthquake epicenter causing this tsunami alert was at San Andreas fault. Based on the data, the earthquake occurring on this fault causes the tectonic plates to slide next to each other. Therefore, the tsunami risk caused by this type of movement is low.

However, this tectonic plate movement may cause underwater landslides. Furthermore, the landslide can cause a tsunami. Therefore, the authority disseminated the tsunami alert via cell broadcast because it worried the Thursday earthquake would cause this phenomenon.

However, after getting more accurate data from the buoys and the observation on the changing sea level, the National Tsunami Warning Center evaluated the early warning. As a result, the authority canceled the warning about an hour after the broadcast.

Californians’ Responses to the Warning

How did Californians respond to the tsunami warning? A report said most residents of California’s coastline were confused about how to respond to this alert. In San Fransisco, citizens were not sure whether or not the cell broadcast alert was a real warning because the emergency sirens were silent.

Despite this confusion, most people receiving the tsunami alert left the coastal areas for higher places. Meanwhile, police officers and fire brigades take some measures to maintain public safety and prevent panic responses from the citizens.

After the cancellation, people went back home from the higher ground. However, most people questioned why the authority had to broadcast the alert in the first place. 

They were rather disappointed with the decision of the National Tsunami Warning Center to disseminate the alert. Nevertheless, it was necessary to take this measure because Californians may not be lucky the next time a big earthquake occurs in the Pacific Ocean.

California’s Earthquake and Tsunami Risks

California is an area with a high risk of earthquakes. Almost every day, there is an quake shaking California. Therefore, Californians are familiar with this phenomenon.

In addition, this region has a high risk of tsunamis. Records said there were over 150 tsunamis sweeping California’s coastal area since 1880. However, many of them are not hazardous. One of the most devastating tsunamis in California was the 1964 tsunami triggered by an earthquake in Alaska.

Meanwhile, the most recent tsunami flooding this region is the 2022 tsunami. The trigger of this seismic sea wave is not an earthquake but a volcanic eruption. Therefore, not all tsunamis in California are due to earthquakes.

In addition, not all submarine earthquakes can cause a tsunami. What would cause a tsunami in California? A tsunami may strike this region if a submarine earthquake with a magnitude of over 6.5 SR causes the tectonic plates to suddenly move up and down.

Consequently, a large volume of seawater will displace. This phenomenon will cause a series of waves to strike the coastal areas. In many cases, the waves are destructive. As a result, they can flood several miles inland.

However, different Californian areas have varied levels of tsunami risks. Some districts have large tsunami hazard areas. They are Orange County, Venice, and Marina del Rey. Therefore, hazardous tsunamis may flood a large part of these areas. 

Meanwhile, some districts have relatively small tsunami hazard areas. However, its density, access, and geographic conditions may cause difficulties for the people to get out of the areas. Examples of these regions are Los Angeles and Long Beach.

The California earthquake tsunami warning on 4th December 2024 alarmed many people in California’s coastal areas. After receiving the tsunami broadcast alert, they went to higher grounds. Thankfully, no tsunami occurred that day. Therefore, the authority canceled the warning.