Let me begin by saying I really hate social media. If you agree, please click the facebook “like”, “share”, and “data mine me” buttons at the bottom of this article.

The New Yorker recently ran an article titled “The Earthquake That Will Devastate Seattle“. That wasn’t the title when you viewed the article on their site- that was the title that The New Yorker put in the metadata on their page so that it would have that title in search engines. The visible title of the article on the page was “The Really Big One”. This means the New Yorker gets to capture clicks from an alarmist headline, while having plausible deniability once you read the article. To see what I mean, go to the article, then bookmark it- that’s when you’ll see the hidden headline appear.

Next, the article includes an oft-repeated quote that says “our operating assumption is that everything west of Interstate 5 will be toast”. Very catchy and totally misleading, and the article did nothing to temper the statement. The New Yorker made a fortune in advertising dollars as all the eyeballs wandered over there, and then to rub salt in the wound people keep sharing the article with us media folks here in the Northwest.

So here’s my lame attempt to correct the article from my powerful perch at Wallyhood world headquarters. New York media elite, take note! Earthquakes create two separate sorts of trouble- shaking and tsunamis. If Cascadia goes, tsunamis will only be along the Pacific coast and will pose no threat to Seattle. The article just states Seattle will be devastated, or toast, then talks up tsunamis. It’s only natural to draw a connection to tsunamis where we live, but that’s not the case from Cascadia.

As for shaking, Cascadia is far enough away from Seattle that shaking will be greatly moderated by the time it reaches Seattle. At it’s closest, Cascadia is 167 miles from Seattle, so the quake effects in Seattle will be somewhat like what Tokyo experienced from the 2011 earthquake off Sendai. The quake will be long lasting (a few minutes), but my understanding is that it will also feel like its magnitude is less than JMA 6 in our area (see the graphic).

The main risk will be liquefaction of soil and harmonic frequencies that can be amplified by the length of time the shaking will be going on. That means trouble for downtown, but not for Wallingford, and downtown will be a ton safer once the seawall is rebuilt. Putting aside the viaduct and seawall, which both could fail in a range of earthquake scenarios, we’ll likely be back to functioning within a week (communications working, water, that sort of stuff).

Finally, the last failure of the article is that there is, in fact, a fault that does threaten to kill us in the thousands, but it’s not Cascadia. The Seattle Fault goes directly under downtown and through Elliot Bay, so all those bad things the article says about Cascadia actually apply to the Seattle Fault. That fault can rupture with about a 7.0, but it will be shallow and violent, similar to the Haitian Earthquake in Port-au-prince. A tsunami in Puget Sound could happen from that quake, along with a lot of destruction to any building that isn’t constructed very well.

The Seattle Fault doesn’t rupture with any predictable frequency or amplitude though, it’s just part of the crumple zone that we’re in. Unlike in California where earthquakes follow a fairly predictable and frequent pattern along clear fault lines, out here our earthquakes are less frequent but all over the place. Imagine two plates grinding past each other (California) vs plates crumpling as they push into each other (the Northwest).

Does it matter that the New Yorker conflated Seattle with the Pacific coast and talked about the wrong fault line? Does it matter that everything they printed had been far better reported by the Seattle Times and even Wikipedia and Crosscut and even Wallyhood long before? Does it matter that they intentionally inserted clickbait and people shared the article and they made tons of money in advertising dollars because of it? OK, the truth is it doesn’t matter very much, but for someone who writes stuff it sure is frustrating to watch.

In terms of local media, Crosscut nobly tried to temper the article with their own coverage. The Seattle Times science writer wrote a fantastic book on earthquakes in the Northwest, called Full Rip 9.0, so the paper has been pathetically running headlines saying “hey, give us the eyeballs and advertising dollars, we’re the ones that deserve them!” Here’s an authoritative PDF that studied cascadia impacts from CREW, which seems to be the official group studying Cascadia (thanks Kyle!) On the flip side, the Stranger performed their solemn duty to hype stupid stuff, so they went ahead and republished the worst inaccuracies as quickly as possible.

Addendum from 7/18 at 11:30, thanks to Kyle for pointing me towards USGS shakemaps: Below is a USGS shakemap for the Cascadia fault, so it’s is a better reflection of shaking intensity than my attempts up above:

Compared to the Seattle Fault shakemap:

Damage listings are on the Modified Mercalli Intensity Scale. In prose form:

Level 6 (e.g. Cascadia in Wallingford): Felt by all. People walk unsteadily. Many frightened. Windows crack. Dishes, glassware, knickknacks, and books fall off shelves. Pictures off walls. Furniture moved or overturned. Weak plaster, adobe buildings, and some poorly built masonry buildings cracked. Trees and bushes shake visibly.

Level 7 (e.g. Seattle Fault in Green Lake): Difficult to stand or walk. Noticed by drivers of cars. Furniture broken. Damage to poorly built masonry buildings. Weak chimneys broken at roof line. Fall of plaster, loose bricks, stones, tiles, cornices, unbraced parapets and porches. Some cracks in better masonry buildings. Waves on ponds.

Level 8 (e.g. Seattle Fault in Wallingford): Steering of cars affected. Extensive damage to unreinforced masonry buildings, including partial collapse. Fall of some masonry walls. Twisting, falling of chimneys and monuments. Wood-frame houses moved on foundations if not bolted; loose partition walls thrown out. Tree branches broken.

Level 9 (e.g. Seattle Fault downtown): General panic. Damage to masonry buildings ranges from collapse to serious damage unless modern design. Wood-frame structures rack, and, if not bolted, shifted off foundations. Underground pipes broken.