Some residents along British Columbia’s coastline were woken by tsunami warning sirens early Tuesday morning shortly after an earthquake struck off the coast of Alaska.
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Here are some things to know about tsunami alerts in Canada:
— British Columbia learns about potential tsunamis from the U.S. National Tsunami Warning Center.
— The centre uses seismometers and sea level measuring stations, which send real time data to national and regional warning centres, to determine whether there’s a risk.
— After receiving notice from the U.S., federal and provincial emergency officials assess the information to determine whether it poses a threat to B.C.
— There are five levels of alerts that B.C. can send out: a warning, an advisory, a watch, an information statement and a cancellation.
— A tsunami warning means that a “flood wave” is possible and a full evacuation is suggested.
— An advisory means there will likely be strong currents and people should stay away from the shore.
— A watch means the government does not yet know how dangerous the situation is, and people should stay alert as they wait for more information.
— An information statement means an earthquake has occurred, or that a tsunami warning, watch or advisory has been issued for another section of the ocean. But in most cases, there is no threat of a destructive tsunami.
— A cancellation is issued when there’s no longer a threat.
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The Canadian Press