The Hunga Tonga-Hunga Ha’apai volcanic eruption on Saturday morning was the shockwave heard around the globe, including here in Alaska, starting at around 3:30 a.m., according to the National Weather Service.
That’s 5,800 miles from the volcano itself deep in the South Pacific. The infrasound measurements from the @alaska_avo confirm that the sound some people heard was coincident with the volcanic pressure wave.
One person in Homer said he distinctly heard the pressure wave at about 4 am.
The eruption of the Hunga Tonga-Hunga Haʻapai volcano was heard across the South Pacific, and eventually as far away as the US.
Much of Tonga, whose capital is 40 miles south of the eruption, is covered in ash and the power is out, with no phone or internet service.
According to the National Weather Service, the pressure wave was not heard in Hawaii, much closer to the eruption.
“The fact that it wasn’t heard closer to the event (e.g., Hawaii) suggests there was an atmospheric component that caused a local/regional bouncing of the sound waves off some portion of the atmosphere. Just speculation. People will be researching this event for many years,” the NWS Alaska reported on social media.
Meteorologists and amateur weather station owners later picked up the pressure wave in places like New Jersey.
People on Twitter said their barometers picked up some unusual atmospheric pressures. These two posted on social media are from Alaska:
Meanwhile, social media users with their iPhones and barometers were crowd-sourcing the reporting on the tsunami that was documented across the West Coast, from piers in Oceanside to Crescent City, California.
The National Weather Service and National Oceanic and Atmospheric Administration were providing real time information on Twitter throughout the day. The tsunami advisory was called off at about 3:30 pm on Saturday, Jan. 15.