Early on January 23rd, a massive earthquake struck the coast of Alaska, causing the western coast of Canada down to the West Coast of the United States to be on high alert for a tsunami. Thankfully, the tsunami warning was lifted, but the West Coast isn’t out of the woods just yet. Citizens of San Francisco have been warned to stay away from the coastlines.
The 7.9-magnitude earthquake, which occurred just after midnight, hit off of Alaska’s Kodiak Island. An area from the Alaskan coast to British Columbia was placed under a tsunami warning, while the entire U.S. West Coast and Hawaii were placed under tsunami watch, which indicates a less severe threat.
Although Alaska saw waves less than one foot high, the National Tsunami Warning Center said that “additional information and analysis have better defined the threat,” leading them to end the alert at about 4 a.m. in Alaska. But even after the tsunami watch was canceled, residents of San Francisco were warned to stay away from the coast for the next 12 hours. The San Francisco Department of Emergency Management tweeted that although there was no danger of a tsunami, currents could still be dangerous for several hours.
Aftershocks of up to a 5.3 magnitude have been felt throughout Alaska in the five hours following the Kodiak Island earthquake. The earthquake’s epicenter was about six miles below the earth, but scientists have recently discovered that earthquakes can occur as deep as 15 miles beneath the earth’s surface.
According to the International Tsunami Information Center, tsunamis are caused when the sea floor or coastal land shifts dramatically in a short period of time. Earthquakes, underwater landslides, and volcanic eruptions can all trigger a tsunami. Earthquakes with underwater epicenters — like the Alaska earthquake — are especially likely to cause these waves.
Thankfully, the Alaska tsunami was small, but if you live in an area prone to earthquakes (and possibly tsunamis), it’s important to practice good earthquake preparedness by assembling an emergency kit in case disaster strikes. And if you live on the West Coast, keep away from the water for a few hours. Stay safe out there, everyone.