Nightmare fuel, and for once I’m not talking Repub politics. Kathryn Schulz, in the New Yorker:
… Most people in the United States know just one fault line by name: the San Andreas, which runs nearly the length of California and is perpetually rumored to be on the verge of unleashing “the big one.” That rumor is misleading, no matter what the San Andreas ever does. Every fault line has an upper limit to its potency, determined by its length and width, and by how far it can slip. For the San Andreas, one of the most extensively studied and best understood fault lines in the world, that upper limit is roughly an 8.2—a powerful earthquake, but, because the Richter scale is logarithmic, only six per cent as strong as the 2011 event in Japan.
Just north of San Andreas, however, lies another fault line. Known as the Cascadia subduction zone, it runs for seven hundred miles off the coast of the Pacific Northwest, beginning near Cape Mendocino, California, continuing along Oregon and Washington, and terminating around Vancouver Island, Canada. The “Cascadia” part of its name comes from the Cascade Range, a chain of volcanic mountains that follow the same course a hundred or so miles inland. The “subduction zone” part refers to a region of the planet where one tectonic plate is sliding underneath (subducting) another. Tectonic plates are those slabs of mantle and crust that, in their epochs-long drift, rearrange the earth’s continents and oceans. Most of the time, their movement is slow, harmless, and all but undetectable. Occasionally, at the borders where they meet, it is not…
… When the next very big earthquake hits, the northwest edge of the continent, from California to Canada and the continental shelf to the Cascades, will drop by as much as six feet and rebound thirty to a hundred feet to the west—losing, within minutes, all the elevation and compression it has gained over centuries. Some of that shift will take place beneath the ocean, displacing a colossal quantity of seawater… The water will surge upward into a huge hill, then promptly collapse. One side will rush west, toward Japan. The other side will rush east, in a seven-hundred-mile liquid wall that will reach the Northwest coast, on average, fifteen minutes after the earthquake begins. By the time the shaking has ceased and the tsunami has receded, the region will be unrecognizable. Kenneth Murphy, who directs FEMA’s Region X, the division responsible for Oregon, Washington, Idaho, and Alaska, says, “Our operating assumption is that everything west of Interstate 5 will be toast.”
In the Pacific Northwest, everything west of Interstate 5 covers some hundred and forty thousand square miles, including Seattle, Tacoma, Portland, Eugene, Salem (the capital city of Oregon), Olympia (the capital of Washington), and some seven million people. When the next full-margin rupture happens, that region will suffer the worst natural disaster in the history of North America…
… [W]e now know that the odds of the big Cascadia earthquake happening in the next fifty years are roughly one in three. The odds of the very big one are roughly one in ten. Even those numbers do not fully reflect the danger—or, more to the point, how unprepared the Pacific Northwest is to face it. The truly worrisome figures in this story are these: Thirty years ago, no one knew that the Cascadia subduction zone had ever produced a major earthquake. Forty-five years ago, no one even knew it existed…
Including some very nifty detail about back-dating the last big event through Native American folk transmission and Japanese tsunami records.
ArchTeryx
The Nightmare Fuel of Republican politics might even intersect with this. When the Big One hits, and 60-70,000 people die, 3-4 major coastal cities are wiped out, and everything on the coast north of CA is suddenly 6 feet lower?
If the Republicans control the government, will they simple let the entire Pacific Northwest die, because they’re a bunch of liberal hippie leftists that didn’t vote for them anyway? It’s telling that I find such a monstrous scenario not only plausible, but extremely likely, particularly if the current crop of revanchist Southerners get the federal trifecta. Katrina on a much grander and more horrifying scale.
Rob
I read the article last night, and will read it again. While I knew something about the geology of Cascadia, I didn’t know about the huge tsunami that hit Japan in 1700. That was a nifty bit of detective work and a very disturbing “peek” of what could happen during a very strong earthquake.
Benw
In 50 years the Pacific Northwest will be a new tropical zone that is overcrowded due to humanity fleeing the increasingly uninhabitable equatorial region, so we’ve got that going for us, which is nice.
Omnes Omnibus
Can’t we have a day of being happy?
chopper
@Omnes Omnibus:
according to the new yorker, no, we’re all gonna die tomorrow.
chopper
is this an article about the cascadia subduction zone or a review of that new earthquake movie starring the rock?
West of the Cascades
I was really relieved when I read the part that “everything west of Interstate 5 will be toast” because I live 30 blocks east of I-5.
More seriously: this has very slowly seeped into the consciousness in Oregon, particularly on the coast, where there are some efforts to set up tsunami evacuation zones and awareness. Some public buildings (e.g. Pioneer Courthouse in downtown Portland) have had seismic retrofitting work done. But there is not, and won’t be, any serious efforts to retrofit private buildings until it is too late.
Omnes Omnibus
@chopper: Then this Cascadia thing is no big deal.
Fair Economist
Uncovering the history of the Cascadia subduction zone earthquakes, especially getting the exact timing of the last one, is so fascinating I manage to distract myself from how horrific the next quake is going to be. Possibly as bad a quake as ever happens on earth, and in an area which is minimally prepared. Adding to the doom factor, the fact that we’re already past the average period between quakes means that the next one is likely to be worse than usual.
chopper
@West of the Cascades:
everything west of the 5 will be toast, but everything east of the 5 will just be plain bread.
wasabi gasp
What a great story. It was a pleasure to read.
mai naem mobile
Well, there goes my dream of moving to the great northwest. Whatevah. Might as well move to a shithole south american country because you know the GOP House will never prep for a disasters because there’s so much $$$ to be made by crony contractors when the disaster hits.
jibeaux
East coast wins!!
Sraly, my hubs has lots of family in Portland, and in the summer I love Portland fierce. But they are pretty much self-parody. One of the cousins recounted with horror a stint in Virginia in which the grocery stores had no cheeses more exotic than smoked gouda.
It’s funny because I love schmancy cheeses but I would never tell a story like that. Because I and many other Southerners grew up in towns where your date night restaurant is Applebee’s, and you tread lightly.
? Martin
@West of the Cascades: Unfortunately, my dad lives in Florence, so he’s totally boned.
chopper
@Fair Economist:
dunno. the average over the last 10k years is something like every 250 years, but over the last 3.5k years it’s been double that. hell, the one before the one in 1700 was like 750 years before.
doesn’t seem like the average is very precise here.
22over7
I didn’t read the whole article, but wouldn’t an event of that size trigger other events? Thinking of that big old volcano under Yellowstone.
Tree With Water
“Our operating assumption is that everything west of Interstate 5 will be toast.” I may be a good couple hundred miles from the southern Oregon border, but that means I’m through pricing kayaks and will have bought one by this coming weekend (at the very latest..).
jnfr
Has anyone brought up the Yellowstone caldera yet? As long as we’re doing apocalypsae?
jl
@Omnes Omnibus:
” Can’t we have a day of being happy? ”
I tell anyone out here who is nervous about earthquakes to head for Wisconsin, that is a safe place. All you have to do is stay out of the snow in the Winter. Not sure that makes them happy or not.
Schlemazel
@jl:
The super volcano that is Yellowstone National Park erupts about every 600,000 years & is overdue, when that goes the Midwest including Wisconsin is going with it and there will be catastrophic damage all the way to the East coast. Maybe we could have a two-fer
MomSense
What about Yellowstone? If that blows we are all toast. Hopefully a couple thousand breeding couples will survive along the equator to rebuild humanity.
MomSense
@Schlemazel:
We are a cheery pair.
different-church-lady
@jl: Yeah, but Scott Walker.
chopper
@MomSense:
dude, imagine yellowstone’s head on the earthquake’s body. niiiiiice.
MomSense
@chopper:
If I ever get a tattoo, that is it. Good reminder to just live and enjoy each day.
Karen in GA
@jnfr: @MomSense: I was just about to mention that.
And here I was starting to get antsy and thinking about leaving Georgia (not that I could right now anyway). Might as well stay put, at least until the heat and humidity become unbearable.
Rob
The Yellowstone caldera is unconnected to the Cascadia subduction zone so there won’t be a “two-fer”.
And on the subject of Yellowstone:
https://en.wikipedia.org/wiki/Yellowstone_Caldera#Volcanic_hazards
eponymous coward
Um, this article’s exaggerating. A lot.
A geophysicist friend put it like this:
(begin quote)
1) Seattle is 200-300 km away. It would be damaged, not destroyed. The strongest shaking they’d feel is about like that of the Nisqually earthquake, and 4 minutes is the maximum estimated duration.
2) There are places in Seattle to worry about. It’s doubtful you live in one. Liquefaction would damage Harbor Island and SODO. Bridges might collapse. There would probably be many landslides. The proposed 99 tunnel could also collapse, if it’s ever finished…but a repeat of the Nisqually earthquake might also do that. In fact, never drive that thing and let’s not talk about it.
3) The Portland and Vancouver (BC) areas could suffer comparable damage to the Seattle area, especially bridges. In fact I fear both would weather it worse, because we simply never think about it.
4) A coastal tsunami’s expected height is 9-12m (30-40′) according to the CREWES reports, not 30m (100′). No model suggests one could travel up the Strait of Juan de Fuca, grow to 100′, then pancake Seattle while sporting a curled moustache and cackling with maniacal laughter. You’re thinking of a Warner Brothers cartoon.
5) The predicted death toll ranges from 3,000 (NISAC est.) – 10,000 (FEMA est.) with up to 30,000 injured. In the Tokohu earthquake, 92% of the dead drowned in coastal tsunamis. Seattle still isn’t on the coast.
6) The economy of the Pacific Northwest will not collapse. The largest employers in Seattle are Boeing, Microsoft, and UW. Coastal fishing hasn’t been a major economic factor in 100 years. More correctly, parts of the coast would become as depressing as Aberdeen. I guess that’s pretty grim.
7) “[N]ot once in recorded history has it caused a major earthquake”. When making statements like this, it’s bad form to then discuss the myriad publications on this subject. Did the author discount 1700 from “recorded history”? Why? Native oral traditions accurately dated the last earthquake for 300 years.
8) The cover image shows a ripped California and Baja California, which is 1,000 miles off.
9) I agree with the article’s assessment that coastal communities are woefully underprepared, and particularly their remarks on schools and critical infrastructure. Those should be moved inland. They’re still not Seattle.
Summary: This article is 20% useful information, 80% amateurish hyperbole. A Cascadia megathrust earthquake poses a much more serious threat to the coastal communities. Why downplay that to scare Seattle?
Suggested references:
http://crew.org/sites/default/files/cascadia_subduction_scenario_2013.pdf
http://pnsn.org/blog/2013/01/24/the-last-cascadia-great-earthquake-and-tsunami-313-years-and-ticking
https://www.reddit.com/r/IAmA/comments/3da1mh/we_are_earthquake_experts_ask_us_anything_about/
(end quote)
Shakezula
@chopper: Talk about a total disaster.
Dan B
22over7; In Seattle there have been regular articles and programs about the Cascadia subduction zone for years, even animations by our semi-competent Department of Transportation showing the collapse of our elevated waterfront freeway. (DOT is working on a tunnel to replace it. It’s already way behind schedule with no restart date. And if it ever gets done it will fill with water in a tsunami…) A big subduction quake could trigger other quakes on other faults. There are a number, including the “Seattle Fault” that runs just a few miles from my house. It is similar to the San Andreas but much smaller. A quake on it would cause the collapse of many buildings and probably I-5, much of which is elevated through the city since it was built mostly on hillsides. The city itself is on thousands of feet of glacial till which can liquify.
Oh, by the way, we go to the ocean every Labor Day with a group of friends. We stay at a little resort near the, drum roll, Copalis River, where the drowned forest revealed the date of the last big one. We’re on a 50′ bluff so would have a ringside seat for the tsunami, if the bluff doesn’t collapse. The drive to the resort goes for miles through “Tsunami Evacuation Route” signs. Of course, miles of broken pavement (after the quake) would make an evacuation … challenging…
My bigger fear for this area is global warming. It seems that it will plunge us into regular droughts. We’re in one now – no rain since mid-May and below average rain for late April to mid-May. Temp’s have been in the 80’s and 90’s, low humidity. Hundred year old trees are dying. The city is full of big, very dry, trees just waiting for a spark and a little wind. Friends are getting scared.
BTW, it’s very unlikely that Yellowstone or even volcanoes in the Cascade Range would erupt. We’d most likely see lahars though.
Greg
@eponymous coward: Thank you for this. I live right on the Columbia just north of Portland. I can now put to rest my vision of a wall of water coming up the Columbia and wiping out everything up to The Dalles. Also, I live in a small flat house made out of some sort I don’t know what but I can’t imagine it breaking and/or collapsing because, well, it’s basically a shipping container.
seaboogie
@chopper: So your toast/bread post which made me laugh must be corrected. Seems that all will be left of *US* will be soggy biscuits and gravy – after the Climate Change hurricanes in the south and east.
Dan B
I agree with Eponymus. Seattle and Portland are too far from the subduction zone. We’d feel moderate shaking that would go on for what would feel like forever. The local faults are much more likely to cause serious damage and there’s evidence they, and not Cascadia, have caused tsunami’s in Puget Sound.
We’re more likely to suffer significant damage from sea level rise. We’re probably not in much trouble of that for 30 or 40 years but that will likely be before the big Cascadia event. Sea level rise would also fill DOT’s new tunnel. Search Bertha to see the clusterf*ck that this is at the moment. ;-)
PeakVT
@chopper: “doesn’t seem like the average is very precise here.”
The complexity of the interactions between the rocks under our feet means that “the average” is highly unlikely to be predictive for most earthquakes or volcanoes. It is, however, precise, at least mathematically.
West of the Cascades
@Dan B: Yes, very unlikely that volcanoes in the Cascade Range would ever erupt. https://en.wikipedia.org/wiki/1980_eruption_of_Mount_St._Helens
zzyzx
Yeah that article is incredibly overhyped. I’ve been having a lot of fun with the west of I-5 thing though since I live like 3 blocks east of it.
magurakurin
I live in Japan. Welcome to my nightmare, Pacific Northwesters. Ya gotta die sonetime.
redshirt
I live in the one safe area of the United States – the mountains of Western Maine.
If you can make your way here after the apocalypse, give me the secret code to gain passage.
SP
I’ve often tried to think of some index for different parts of the world to indicate how likely Nature is to kill you. Northeast, blizzards and Lyme disease. FL alligators hurricanes. Midwest/plains tornadoes. CA fires mudslides drought earthquakes. I think the northeast is safest.
redshirt
@SP: Blizzards and ice storms are the worst interior Northeast can offer. Hurricanes also on the coast, and tsunami threats I guess. When the Canary Islands go tits up, for example, NYC and Boston are screwed.
ruemara
You people with your facts. You’re completely ruining my dream of cheap housing in SF & LA.
gbear
If you go looking for the Cascadia subduction zone on YouTube, you’ll find enough hour-long docuramas to waste an entire Saturday afternoon and evening. Don’t ask me why I know that…
oldster
I know the portion of I-5 between Portland and Eugene. It runs in the bottom of the Willamette Valley. So it’s kind of weird to refer to I-5 as an important barrier between where the tsunami will cause damage, and where it won’t cause damage.
If the tsunami gets over the Coast Range, then it won’t stop at the shoulder of southbound I-5.
Is there any reason to think it can get over the Coast Range? That’s a few thousand feet, not a few hundred feet.
So it seems a bit misleading to say that the tsunami will affect: “…everything west of Interstate 5 covers some hundred and forty thousand square miles, including Seattle, Tacoma, Portland, Eugene, Salem (the capital city of Oregon),….”
Maybe the Willamette Valley will suffer from the earthquake portion. But I doubt if the tsunami will affect it.
Jeffro
I feel for the poor school principal in the article who goes to work every morning knowing that if today’s Quake Day, all of his students and teachers are going to die.
Villago Delenda Est
I live something like 6 miles west of I-5, so I figure I’m toast.
Mr Stagger Lee
I live 1 mile of I-5, I can hear the traffic in the still of the night, oh well if Rainier doesn’t kill me Cascadia will, oh by the way did I tell you about the increased train traffic carrying more oil running 500 yards from my house?
gwangung
@eponymous coward: Heh. Having actually been a geologist in a past life, I’d put it 40/60 or even 45/55.
The problem’s more in how the man made structures will withstand the quake…and I trust the engineering less than I do the science. I agree the tsunami problems will be minimal. Liquefication will probably be more a problem in the southern part of the Seattle area (Rainier Valley, etc.), and not just SoDo. The energy release is not something to be sneeze at, and it’s whether people actually follow the codes or retrofit their own buildings. THAT’S where the economic problem is going to come from.
Death Panel Truck
I live in Pasco, Washington, so my family and I are pretty much safe. I grew up downwind of nine plutonium reactors*, so the threat of natural disaster never scared me half as much as the man-made kind. Supposedly there are fault lines running through the Hanford reservation, so maybe we’ll have a combination natural/man-made mess to deal with here one of these days. The Columbia Generating Station is still operational.
*still remember every one of them, in order of their construction: B, D, F, H, D-Replacement, C, K-West, K-East, and N. High school quiz from the seventies.
Another Holocene Human
@eponymous coward: To be fair, anything even halfway as bad as that will wash out big parts of the BNSF main line that stupidly hugs a cliff/coast and gets mudslid on an annual basis anyway. So not being able to ship stuff in and out will be another fun aspect of this disaster as well as costing BNSF billions. Oh, and Amtrak uses that line too.
Another Holocene Human
@Dan B:
WTF? That’s terrible!
JustRuss
@eponymous coward:
I was just at the Oregon coast, and schools are getting moved to higher ground. Of course it’s not happening overnight, but a lot of older schools need to be replaced anyway for structural reasons, and planning for tsunamis is part of the process.
tom
@redshirt:
Paul LePage is your governor, I’ll take my chances with a catastrophic tsunami thank you.
mclaren
(Sigh.)
Once again, online communities fall prey to the most wildly overblown hysterical hyperbole. We went through this with the BJ commentariat going apeshit over the supposed radioactive “death cloud” from Fukushima (where are all the dead bodies?) and then we went through it again with the ludicrous fantasies about America suffering from a vast ebola outbreak (reality check: more Americans married Kim Kardashian than died of ebola).
Source: reddit AMA with John Vidale, director of the Pacific Northwest Seismic Network, Debbie Goetz of Seattle’s Emergency Management Office, and Sandi Doughton, science writer at The Seattle Times and author of Full Rip 9.0: The Next Big Earthquake in the Pacific Northwest.
In short, the New Yorker article is a piece of total scare-tactic bullshit. Pay no attention. It’s horseshit.
Statistical rule of thumb: the larger a disaster, the longer the odds against it. 9.0 earthquakes are so rare that it’s unlikely anyone living in America today will experience one during their lifetime.
donald
If you read the article carefully you know the author doesn’t literally mean everyone west of I-5 is underwater–there was one carelessly written paragraph that implied that, but later she gives an estimate of 13,000 dead and even we East Coasters know there are more people in Portland and Seattle than that. She is apparently talking about the area that would likely suffer serious damage–in some places, catastrophic damage.
The article is a bit hyped,but people always hype disasters of every sort. Take any disaster, no matter how catastrophic is it in reality, and someone will make it sound even worse than it was in reality. Sounds funny, but it’s true. The important point is that thousands of people will likely die because not enough preparation is being done.
Denali
I knew it! Catastrophe!
Heliopause
What happens first, the Cascadia Big One or the Mt. Ranier Lahar? The 99 tunnel collapse or the 520 bridge sinking? What a fun state we live in.
mclaren
@donald:
Fewer people will die in this hypothetical “really big one” than die every year because they refuse to get vaccinated for the flu.
Want to save a lot of lives? Pass a law forcing people to vaccinate their kids for everything — mumps, chicken pox, flu, scarlet fever, polio, etc.