A strong 7.1 earthquake struck near Mindanao, Philippines today, prompting the Tsunami Warning Center in Ewa Beach, Hawaii to issue a series of alerts for locations in the Pacific. The earthquake struck at 6.5 North 126.8 East at a depth of 50 km; it struck at 17:46 UTC.
According to the Tsunami Warning Center, “based on all available data, hazardous tsunami waves are forecast for some coasts.” In addition to identifying those tsunami threat areas, they have also issued bulletins saying a tsunami is not expected for Hawaii nor the U.S. West Coast, and also added that a Pacific-wide tsunami is not expected at this time.
According to the latest forecast from the U.S. Tsunami Warning Center, tsunami waves reaching 0.3 – 1 meters above the tide level are possible for some coasts of the Philippines while tsunami waves under 0.3 meters are possible for the coasts of Indonesia, Malaysia, Palau, and Yap.
“Actual amplitudes at the coast may vary from the forecast amplitudes due to uncertainties in the forecast and local features. In particular, maximum tsunami amplitudes on atolls and at locations with fringing or barrier reefs will likely be much smaller than the forecast indicates,” the Tsunami Warning Center said in a bulletin.
“A tsunami is a series of waves. The time between wave crests can vary from 5 minutes to an hour. The hazard may persist for many hours or longer after the initial wave,” said the Tsunami Warning Center. They add, “Impacts can vary significantly from one section of coast to the next due to local bathymetry and the shape and elevation of the shoreline. Impacts can also vary depending upon the state of the tide at the time of the maximum tsunami waves.”
Tsunamis can be extremely hazardous, even smaller ones that are under one meter in height. The Tsunami Warning Center says that people caught in the water of a tsunami could drown, be crushed by debris in the water, or be swept out to sea.
This tsunami threat arrives less than 2 weeks after a major earthquake struck Alaska, triggering tsunami alerts then too. The July 29 8.2 Alaskan earthquake triggered tsunami alerts across Alaska, Hawaii, and the U.S. West Coast.