Source: U.S. Tsunami Warning System Note: Sensor data is available only for selected locations, mainly in North America. The New York Times
Alerts for a potential tsunami were issued for parts of the Aleutian Islands in Alaska, Hawaii, the coastline of Russia and Japan after a powerful 8.7-magnitude earthquake struck in the North Pacific Ocean off Russia’s northern Pacific coast, according to the U.S. Tsunami Warning System, which is part of the National Weather Service.
A tsunami warning — the highest level of alert — was in place for parts of the Aleutian Islands.
A tsunami advisory, which means people should get out of coastal waters and stay away from beaches and waterways, was issued for other parts of the Aleutian Islands. A tsunami watch, which means experts are evaluating the threat, was issued for the west coast of the United States, Canada, Hawaii and Guam.
U.S. officials said a tsunami threat exists for parts of Russia, the Philippines and Japan, but they deferred to authorities in other countries for official advisories and warnings.
Tsunamis are a series of long waves caused by a large and sudden displacement of water in the ocean, usually from a large earthquake on or below the ocean floor. Tsunamis radiate in all directions from the epicenter and can cause dangerous coastal flooding and powerful currents that can last for hours or days.
Experts warn that just before a tsunami hits shore, seawater can first be drawn out to sea — exposing large swaths of beach and giving people along the water a false sense that a coast is safe.
As more information becomes available, officials may update, add or cancel tsunami alerts.
Camille Baker and Natasha Cornelissen contributed reporting.
