These things happen without much warning. Today, January 15, 2022, a tsunami alert was posted for much of the Pacific Rim, implicitly including Whidbey Island. An underwater volcano erupted on the other side of the Pacific Ocean, which was terrible and sudden for them, but also why we had some warning. We also had less to worry about because some of the energy had dissipated by the time it got here. This is not the first. It won’t be the last. And for those who want to learn more, there’s more than enough to keep a person busy. Fortunately, we know more now than we did even a decade or so ago.
(Note: This is an important issue, but one that is relatively well studied. The following links are there to educate, not frighten. The Nick Zentner video near the bottom may be a good place to start for a conversational description, not just a bunch of data and videos. He’s a professor from Central Washington and decided to describe the realities and allay some of the fears of the Cascadia situation.)
First, the eruption near Tonga. It was fairly far around the planet from Whidbey.
The final data will take a while, but the satellite imagery may be more instructive. The blast as about the size of the north island of New Zealand, used for scale.
Tsunamis on Whidbey are rare, but common enough that signs are posted in critical points around the island. Most of the time they may be ignored, but they’ll probably become easier to notice, now, for a while.
Island County Emergency Management has issued maps for a variety of situations, including tsunamis.
Tsunamis are natural, especially along the Pacific coastlines. We’ve seen tsunamis started in Asia, Oceania, and from the west coast of both Americas. Our coastline sends tsunamis back the other way, too. One tsunami that hit Japan in 1700, exposed the regional quake and tsunami danger that gets the most press: the Cascadia Fault that’s several dozen miles off the Olympic Peninsular stretching into California and into Canada. NOAA (National Oceanic and Atmospheric Administration) as well as USGS (United States Geological Survey) and others like PNSN (Puget Northwest Seismic Network) have studied our area and produced simulations of what could happen here.
The regional view:
A local view:
If you look back up at the Tsunami High Ground Map, you can see tsunami zones throughout the coastal areas. That’s because, while tsunamis can come from anywhere on the globe, including within our region, Puget Sound also experiences tsunamis caused by quakes and slides around Whidbey. One particular source is the Seattle Fault where a quake there can cause a tsunami to arrive on the south end of Whidbey. (Discovering Whidbey Island’s Tsunami Funnel)
Local landslides can cause them too. (Pardon my inability to reference the one that was caused by a slide on Camano that tragically impacted Hat(Gendey) Island.)
There’s always more to mention because our area is so geologically active that it is heavily studied. One useful video better describes the situation with our offshore quake and tsunami generator.
Of course, most people aren’t going to read this until long after this tsunami threat is past. In the time it’s taken to write this post the first wave has probably already subsided. Subsequent waves can continue to arrive for a few hours, and may be larger than the first, but hopefully the word has gone out and people acted responsibly. Here’s an example of what some other West Coast locations experienced.
Notice that most of the waves were less than a foot, but one reached 4 feet. A quick check of YouTube for any “Whidbey Tsunami” videos from today shows nothing, and maybe that’s what we got.
We live close to nature on Whidbey Island. Today is yet another reminder that that beauty comes with power, too; and we need to respect it. One irony during this event: we’re experiencing dense fog, so it can be hard to even see the Sound, let alone see a wave – unless you’re too close to it.
Stay on high ground. Be safe. Take care. And maybe refresh that Emergency Preparedness Kit.
PS Just after I posted this the emergency phone alert blared. Unfortunately it went away before I could read or capture it. Stay tuned.