An earthquake off Russia has set off tsunami warnings and advisories. Here’s what to know

HONOLULU AP A powerful earthquake that struck off the coast of Russia generated tsunami warnings and advisories for a broad section of the Pacific including Alaska Hawaii and the U S West Coast The quake registered a magnitude of and was centered off the coast of the Kamchatka Peninsula according to the U S Geological Survey The temblor struck early Wednesday local time which was still Tuesday in the U S Here s what to know about tsunamis and their warnings What is a tsunami Tsunamis are waves triggered by earthquakes underwater volcanic eruptions and submarine landslides After an underwater earthquake the seafloor rises and drops which lifts water up and down The vigor from this pushes sea water that transfers to waves Multiple people think of tsunamis as one wave But they are typically multiple waves that rush ashore like a fast-rising tide Several tsunamis are small and don t cause damage Others can cause massive destruction In a magnitude earthquake struck off the coast of Indonesia causing waves that leveled remote villages ports and tourist resorts along the Indian Ocean across Southeast and South Asia Particular people died How do people find out if there s a tsunami warning In Hawaii crisis bureaucrats blast alerts to people s cellphones on TV and radio and sound a grid of sirens In Alaska specific communities have sirens and information is also available on weather radio or general radio broadcasts Official accounts on social media and cellphone push alerts spread the word In selected places local bureaucrats have relayed warnings door to door Earlier this month after another earthquake off Alaska s Aleutian Islands society safety departments in King Cove and Unalaska sent alerts urging those in coastal areas or those that could see inundation to seek higher ground What should I do if I get a tsunami alert Administration urge people to move to higher ground when they have indications a tsunami will arrive In Hawaii the state s exigency management agency directs people to check maps and to evacuate if they are in a tsunami hazard zone It also tells people to stay at least feet meters away from inland waterways and marinas connected to the ocean due to the possibility of wave surges and flooding Various communities have buildings designated on higher ground as meetup points during tsunami warnings such as a school while others might just urge residents to retreat up a hillside In the U S the National Weather Facility has different levels of alerts A warning means a tsunami that may cause widespread flooding is expected or occurring Evacuation is recommend and people should move to high ground or inland An advisory means a tsunami with expected for strong currents or dangerous waves is expected or occurring and people should stay out of the water and away from beaches and waterways A watch means that a tsunami is realizable and to be prepared How long does it take for tsunamis to arrive It depends on how far the epicenter of the earthquake is from a coastal area It could take just minutes for waves to hit land next to the site of a major quake It could take hours for tsunamis to cross the Pacific Ocean The speed of tsunami waves also depends on ocean depth They journey faster over deep water and slow down in shallow water What effects have been noticed so far The Japan Meteorological Agency commented a tsunami measuring feet centimeters was detected in Tokachi on the southern coast of Hokkaido the northernmost of the country s main islands In Alaska the National Tsunami Warning Center estimated wave heights could reach feet to feet centimeters to meters at Shemya and up to feet centimeters at Adak which has about people and is the southern-most public in Alaska Selected waves have likely already hit Alaska s remote far western islands but weren t expected to reach Cold Bay until p m local time A tsunami warning was issued for Hawaii with the first waves expected to arrive after p m local time Much of the Pacific coast of North America spanning from British Columbia in Canada to down the U S West Coast and into Mexico was under a tsunami advisory The Oregon Department of Emergency Management declared on Facebook that small tsunami waves were expected to reach parts of the state s coastline starting around p m local time with wave heights between to feet to centimeters It urged people to stay away from beaches harbors and marinas and to remain in a safe location away from the coast until the advisory was lifted This is not a major tsunami but dangerous currents and strong waves may pose a danger to those near the water the department stated Waves up to feet meters were also feasible in Crescent City California with smaller waves several expected to be less than foot in other communities along the West Coast Mexico s navy warned that waves between to feet to centimeters were attainable on its coast Source