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Why Are We So Bad at Predicting Earthquakes? (telegraph.co.uk)
In the wake of major earthquakes in both Japan and Ecuador, one British newspaper asks: Why are we so bad at predicting earthquakes? In 2015 seismologists told Vice, "The more we study them, the harder they look to predict, and "there's a shortage of instrumenation." But today the Telegraph newspaper concludes that we actually have two problems: first, "science is hopeless at predicting earthquakes and, second, we keep building cities on major fault-lines..." They cite a new book called Earth-Shattering Events which reports that nearly half the world's large cities are in earthquake-prone areas, adding, "we don't just build our cities on fault-lines, we also tend to rebuild them, in the same place, but no more robust, time and time again." In 1976 one quake in China killed more than 750,000 people, while a 2004 quake in Indonesia killed 170,000. "The Earth will move and there's not a thing we can do to stop it," the Telegraph concludes, arguing that we need to learn more from our past.
Because we haven't prosecuted enough scientists for failing to predict earthquakes. Italy is on the ball. Get with it, world!
"we don't just build our cities on fault-lines, we also tend to rebuild them, in the same place, but no more robust, time and time again."
I can't speak for everywhere, but in California, the construction standards are much higher after the 1989 earthquake.
Boston, however, is in serious danger because of so many tall buildings built of brick (and other reasons).
"First they came for the slanderers and i said nothing."
Simpler answer,
We don't know very much.
This applies to most things, not just earthquakes,
Medicine, (why do we need so much testing? because we are taking a stab in the dark and seeing if it works)
Weather, how many are forecasts inaccurate.
In fact any system that is even mildly complex we blunder our way through, even an area like programming, where we know exactly how the system works, and all inputs, we still need to test rigorously in to ensure that we haven't made to may mistakes.
Also earth quakes are probably a chaotic system so we probably cannot get close to even knowing enough inputs to predict them, no matter how much we explore. (It doesn't mean we shouldn't try)
we know the sort of geology that is found in earthquake areas, so we can predict where they will happen; by measuring strain, etc, we can get an idea of when they will happen and what sort of magnitude. The trouble is that we (== common people, non scientists) expect answers that fit in with my everyday rulers and clocks (ie a few miles and days), but geological events are measured differently: hundreds of miles and decades/centuries; so the margins of error are too great for what we want.
If I place a vase of roses outside on a summer's day I can expect the flowers to be visited by bees, but I cannot predict which flower will be visited first or the minute when the first bee will come.
Honest question: What would it take to make that happen? Money, time or technology?
It's not even know whether or not it is possible in principle to predict when a major earthquake will happen. If you look at a time series of magnitude measurements at a particular fault it looks like something coming out of a random number generator. It might be predictable, but it's not obvious that it is.
Some systems are fundamentally unpredictable because their long-term behaviour depends on arbitrarily small differences in the initial state of the system.
More seriously, cities typically are there for a reason. And the reason usually doesn't go away just because there was an earthquake.
I mean, what are you going to do, have everyone move houses and buildings to other locations? What a waste of time.
Given a minute or so of warning, you can:
1. Stop trains, so they don't come off the track.
2. Stop additional cars from entering tunnels.
3. Pretension dampers in tall structures
4. Sound an alarm to warn people in warehouses and stores to move away from shelves.
5. Pull up automatic safely webbing to prevent pallets from falling off racks.
6. Stop and lower cargo on forklifts.
7. Start powering down heavy machinery
8. Stop people from entering elevators
9. Open fire station doors, so they don't jam closed.
10. Shutdown the flames in furnaces and water heaters
11. Start reducing gas pressure in pipelines.
12. Warn people on beaches to start moving to higher ground.
13. Start backup diesels for emergency services.
14. Retract the control rods from nuclear reactors.
Since seismic waves travel about 5 km / sec, you can give useful warning to people further away just by quick detection. Of course, prediction would be better.
Absolutely, the city would be evacuated. That's much higher prediction accuracy than we can get with hurricanes, yet cities are evacuated for those, sometimes even several times per year.
Of course, the minority, whor are living in structures engineered to withstand very high earthquake loads would remain behind. But at least they'd have plenty of warning to strap down appliances before-hand, and stay away from dangerous spots on that day.
Not to mention there would be a rush on home-improvement stores and contractors, as everyone rushes to reinforce their shoddy old buildings.
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