Is Los Angeles ready for a massive tsunami? How about Honolulu or Seattle?
In Chile, more than a million people evacuated their homes in the wake of an 8.3-magnitude earthquake and tsunami alert on Wednesday night, keeping the casualty count below a dozen.
Compare that to 2010, when an 8.8-magnitude temblor caused more than 500 deaths, many of them due to a massive tsunami. Back then, the government failed to issue an early tsunami alert, resulting in criminal charges against several officials and prompting new evacuation drills and emergency response procedures.
Evacuating a million people and having only a few deaths is “phenomenal,” Costas Synolakis, director of the University of Southern California’s Tsunami Research Center, told NBC News.
“It’s a positive message for us,” he said. “If the Chileans can evacuate a million people in 15 or 20 minutes, we should be able to do it as well.”
But there is no guarantee that Americans are as prepared as people in Chile.
Tsunami danger zones
It’s possible that a tsunami could hit the East Coast. But it’s cities along the Pacific Ocean’s “Ring of Fire” that are most at risk.
Hawaii is constantly threatened by tsunamis that originate far away. Those big waves can be deadly for some swimmers and boaters, but overall they’re not the stuff of natural disaster nightmares.
More dangerous are local or “near-field” tsunamis triggered by powerful nearby quakes. Think of the deadly Indian Ocean tsunami in 2004 that contributed to more than 230,000 deaths. Coastal towns in Washington and Oregon run the highest risk of encountering these disasters. California and Alaska are also at risk.
Last month, a study found that an earthquake off the coast of Southern California could send a 23-foot-high wave more than a mile inland into the cities of Ventura and Oxnard.
Escaping a tsunami
With distant tsunamis, people have hours to react, which makes it easier for local governments to warn people away from the coast. Some U.S. cities — including many in Washington state and Hawaii — use sirens that go off when a tsunami is coming.
Others, like those in Los Angeles County, use opt-in emergency alerts to contact people with text messages, emails and pre-recorded phone messages. Beaches will often have law enforcement and lifeguards warn people away and use bullhorns to get the attention of swimmers and sunbathers, according to Nathan Wood, a research geographer with the U.S. Geological Survey.