Thinking about the tradgedy that occured in the Pacific this weekend, I began to think about the potential for disaster here in New York.
In 1949, the volcano/island of Cumbre Vieja, in the Canary Islands erupted. During that eruption, part of the island slipped several meters into the Atlantic. It is predicted that at some point in the next several thousand years, the volacano will erupt again, causing the western half of the island (about 500 billion tons of rock) to slip into the Atlantic. This will cause a megatsunami that will completely destroy several cities on the U.S.'s Altantic seaboard (not to mention other areas in the Carribean, Africa and possibly Europe).
A megatsunami would travel (according to the linked Wikipedia article) at 500 mph and could reach up to 20km inland.
I don’t know the exact distance from the Canarys to New York, but I figure (based on a guesstimate) that 1500-2000 miles is about right. So, that would give us about four hours to evacuate the eastern seaboard (assuming we know about the megatsunami right away, of course. Even if we don’t it shouldn’t take too long to show up on satelitte photos).
Is such a feat even remotely possible? Could the eastern seaboard (or even just New York, using an example) be evacuated of the majority of it’s residents in that time?
How the heck could it be possible to evacuate more than half the people in NYC in 4 hours??? This would take a lot of starships in orbit with teleporters. Best that could be hoped for is people would be warned a tsunami was coming. I’d think this would save more lives than if they were caught offguard.
The actual evacuation time would be much less than 4 hours. Subtract the time it takes to determine what is happening, the time it takes to get to the people who can do this, the time it would take them to make what might be a career killing decision, and the time to get the news out. You might have something like an hour, if you could get the populace to buy the story.
How far can you go in NY, for instance, in meag-rush hour traffic in an hour?
Rhubarb’s well thought out answer seems about right to me.
It happened on the Indian Ocean side of Sumatra. Sumatra blocked most of the wave energy from reaching anything to the east, so no, the Pacific basin wasn’t affected.
Had this sort of thing happened off of the coast of say… Japan, you would’ve heard about destruction all around the pacific basin.
Well, yes. But Indonesia, like Australia and the United States, borders more than one ocean. As far as I know, the only Indonesian deaths from the tsunami have occurred in Sumatra, on the Indian Ocean. That’s why I was surprised when Zev called it a “tragedy…in the Pacific”.
I believe the tsunami traveled down the Strait of Malacca (I’ve seen pictures of damage in Penang), but as far as I know, that’s been the limit of damage towards the east.
Rhubarb: Precisely what I thought when I first saw the thread title. It’s really pretty obvious: No major American city, let alone one where as much of the population is on islands, has the transportation infrastructure to support everyone needing to leave at once. In fact, I think pretty much all of the Cold War-era Civil Defense research found that out. (I’d be interested in being proven wrong, as always.)
Roads are expensive and bridges multiply so. Tunnels are a huge expense. Nobody builds more than they need to, and so far we (the USA) have never needed to do mass evacuations. Given that even in New York City enough people own cars to make parking expensive and generally a pain, I don’t even want to imagine a panicky, desperate mob trying to get the hell upcountry.
Air transit could reduce the load, but not by much, I wouldn’t imagine. You need coordination to mobilize helicopters (the only option in the main urban centers), not only to find them and get them active but to get enough people on them to make a difference. How will you prevent every one that touches down from being mobbed by the aforementioned panicky mass? Where will they all land? I can’t imagine the horrors of trying to fly a chopper down between skyscrapers to a city street, and every building that has a pad on the roof would be full past capacity.
Sea travel is appealing, given that the docks probably have a larger capacity than the roads and viable landing sites, but where do the ships, in this scenario, go? Keep in mind that all of the East Coast has the same problem, at least all of the American East Coast. This would depend on how much warning we’re all given, but trying to make the Panama Canal would be suicide in the case I’m thinking of. You’d end up heading right into the jaws of the megatsunami. Going north leads to the problem of where all those boats can dock, and going to Europe might not be much better than going to Panama given travel times.
How well can New York buildings, and US buildings in general stand up to these things? Obviously a suburban house is gone, but what about sky-scrapers and even apartment buildings? Could we “evacuate” to sturdy, tall buildings and wait it out?
IMO, if I was in NYC when the alert sounded, I would steal a small boat and head straight out to the deepest water I could get to. Off shore, the wave is just a hump of water and without special instrumentation you would never know it went under you. Shallow water is the problem. This is not a rogue storm wave but a tsunami . Two different things…
Offshore a few miles. Wherever the continental shelf drops off into the deep ocean - what, 10 or 20 miles or so out? At that point the tsunami is a fast-moving, barely noticeable bump in the water and no threat to anything.
I will say no but I also doubt the danger being threatened by this supposed future megatsunami. I’ve known a fair number of geologist types in my life and they tend to think nearly all of the earth’s processes is an obvious warning of the future destruction of the planet.
When the earthquake hit Kobe, Japan in 1995, the advice we got in Hawaii was simply to head to high ground. City folk and tourists were instructed to retreat to the 5th story or higher of their buildings or a neighboring building if their’s was too short. Fortunately, the wave was nothing and the whole thing just turned into a free day off from school. But at least someone out there thinks it’s reasonably safe to use a tall building for shelter from a tsunami. Or maybe that’s the only thing they could think of at the time. I’m sure some of the stuff you hear to do in an emergency is just for your own peace of mind.
Here is the only internet info I can find on it right now.
The other option aside from getting to high ground was to take a boat out into deep water. Lots of people have their own boats, but obviously this wasn’t a choice for everyone.
The width of a continental shelf is highly variable, depending on the particulars of the geologic setting. Off the coast of New York City, it is more than 100 miles wide. Please don’t guess if you don’t know - this is GQ, not IMHO.
In any event, unless you have ready access to a fast ship (and most people would not), leaving by sea is not a viable evacuation method. In fact, there really is no effective evacuation method for a city the size of NYC in the time frame of the OP, or even those portions of NY-NJ-LI that would be most vulnerable. And that’s just looking at straight logistics, not considering the human factors of panic and confusion. Rhubarb has it right.
Best that could be hoped for is people would be warned a tsunami was coming. I’d think this would save more lives than if they were caught offguard.