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Alaska, Hawaii, and Parts of America’s West Coast May Be Wiped Out By Giant Tsunami, Scientists Warn

Experts predict a 15 per cent chance of massive earthquake hitting America in the next 50 years

Aftermath of the tsunami in Fukushima, Japan in 2011. (Photo: © Smallcreativeunit5 | Dreamstime.com)

By Akerele Christabel

May 24, 2025
4:08 pm
Los Angeles, CA

March 11, 2011 saw the island country of Japan terribly shaken by a 9.1 earthquake as a result of mounting pressure along a deep ocean trench off the northeast coast which collapsed the fault. The quake began below the seafloor, 43 miles east of the Tohoku Region, jolting part of the seafloor upwards by 30 feet. The force of the temblor thrust Honshu, Japan’s biggest island, about 10 feet to the east. Seismographs registered the quake’s magnitude at 9.1, the most powerful recorded in the country. In less than a minute after the quake began, early warning systems fed quake data into computer simulations. Computer models processed tide gauge and deep ocean gauge observations throughout the Pacific Ocean. These systems churned out forecasts of when destructive tidal waves, or

Seismographs registered the quake’s magnitude at 9.1, the most powerful recorded in the country. In less than a minute after the quake began, early warning systems fed quake data into computer simulations. Computer models processed tide gauge and deep ocean gauge observations throughout the Pacific Ocean. These systems churned out forecasts of when destructive tidal waves, or tsunamis, might arrive at coastlines in Asia and the Americas, and how big they might be.

GPS systems positioned high above the nation’s atmosphere detected signals from their quake. The satellites sent their usual radio signals to the Earth. The pulses intercepted and recorded atmospheric disturbances caused by the quake. When they arrived at the ground receivers, the radio signals carried vital information about the quake that could improve tsunami early warning systems and get people out of hazard zones faster.

The same satellites can also detect disturbances in the ionosphere caused by tsunamis. When a tsunami forms and moves across the ocean, the crests and troughs of its waves compress and extend the air above them, creating motions in the atmosphere known as gravity waves. These undulations of gravity waves are amplified as they travel upward into an atmosphere that becomes thinner with altitude. When they reach the ionosphere, the gravity waves also can be detected using the constellations of GNSS satellites circling Earth. However, the signals did not arrive in time enough to save 15,000 people from dying. This time around, warnings have arrived 50 years.

Virginia Tech geoscientists warn that a magnitude 8.0 earthquake might hit the regions of Alaska, Hawaii and parts of the American West Coast within the next 50 years. Their findings put the chances of such happening at 15 per cent.

The aftermath of the earthquake might be a 1000-foot tall “mega tsunami” that could potentially see large parts of America disappear from the map if such an earthquake hits a specific active fault line. The fault line stretches from Northern Vancouver Island to Cape Mendocino, California. According to the scientists, if an earthquake like that truly occurs, cities like Seattle and Portland, Oregon could be flushed away and coastal land could sink by as much as 6.5 feet, according to the findings.

Deadly ordinary tsunamis stand at a few feet tall and cause great damage. However, they pale in comparison to mega tsunamis which rise to extreme heights, often rising to hundreds of feet.

“The expansion of the coastal floodplain following a Cascadia subduction zone earthquake has not been previously quantified, and the impacts to land use could significantly increase the timeline to recovery,” said Tina Dura, lead author of the study and assistant professor in Virginia Tech’s Department of Geosciences.

Unlike gradual climate-driven events, the forecasted earthquake would “happen within minutes, leaving no time for adaptation or mitigation.

In 2020, Attila Komjathy, a scientist at NASA’s Jet Propulsion Laboratory, and his colleagues took the GPS data from the Tohoku earthquake and tsunami, as well as from other earthquake and tsunami events, and developed a new approach to assist in the ongoing development of timely tsunami detection systems. “The goal is to detect tsunamis and warn the coastal communities in real time,” Komjathy said. Komjathy’s group relies on GPS data archived by NASA’s Crustal Dynamics Data Information System (CDDIS), among other sources, for their project.

The new approach, called Variometric Approach for Real-time Ionosphere Observation, or VARION, was designed under the leadership of Mattia Crespi of Sapienza University in Rome, Italy. The main author of the algorithm is Giorgio Savastano, a doctoral student in geodesy and geomatics at Sapienza and an affiliate researcher at JPL, which conducted further development and validation of the algorithm.

However, Komjathy said they need access to more real-time GPS data streams, specifically from countries located in the Pacific Ring of Fire, a string of volcanoes and hot spots of seismic activity around the edges of the Pacific Ocean. “Some countries in this area are not always very keen on sharing data,” he said. “We need real-time access to data. Otherwise we cannot really process a global network of GPS stations.”