A massive tsunami is at a high risk of striking Hawaii, researchers have found.

Scientists have determined that there is a 9 percent chance of a magnitude 9 earthquake erupting off the Aleutian Islands within the next 50 years, sending a tsunami hurtling toward Hawaii that would have a devastating impact, according to a statement from the University of Hawaii at Manoa.

A magnitude 9 earthquake off the Aleutians, which are off the coast of Alaska, would send a tsunami speeding across the ocean toward Hawaii, resulting in devastating effects that would cost billions of dollars and affect 300,000 people.

Scientists studied “paleotsunamis” from eons ago to come to their conclusions, creating a model for a magnitude 9 earthquake that closely matched historical reality. They also studied the five largest earthquakes since 1900.

“Necessity is the mother of invention,” Rhett Butler, lead author and geophysicist at the UHM School of Ocean and Earth Science and Technology (SOEST), said in the statement. “Having no recorded history of mega tsunamis in Hawai‘i, and given the tsunami threat to Hawai‘i, we devised a model for Magnitude 9 earthquake rates following upon the insightful work of David Burbidge and others.”

The statement notes: “Using the probability of occurrence, the researchers were able to annualize the risk. They report the chance of a Magnitude 9 earthquake in the greater Aleutians is 9% ± 3% in the next 50 years. Hence the risk is 9% of $40 billion, or $3.6 billion. Annualized, this risk is about $72 million per year. Considering a worst-case location for Hawai’i limited to the Eastern Aleutian Islands, the chances are about 3.5% in the next 50 years, or about $30 million annualized risk. In making decisions regarding mitigation against this $30-$72 million risk, the state can now prioritize this hazard with other threats and needs.”.

The team is trying to figure out how this analysis could be extended to smaller earthquakes around magnitude 7 or 8.