Reading about the nearly 10,000 presumed dead in Indonesia and elsewhere, I am stunned. Sunbathers were washed away by the killer wave.
Of course, a disaster of this magnitude will kill people; I accept this. But sunbathers? We don’t have the ability to notice that a killer wave is coming and warn sunbathers to get to high ground?
What, if any, are our capabilities to spot tsunamis following undersea quakes?
We probably have the technology to do it–at a cost.
Detecting changes in water density at a distance is probably not within our current capacities. (Some squids or ASW folks might be able to correct me, here.) So the best approach would be to scan the ocean surface with radar or to have sufficient number of weather buoys to record their passing. The problem is that a tsunami at sea is simply a slightly larger than normal wave. It does not become a “tidal wave” (in the common American movie-goer parlance) until it reaches shore, so we’d have to establish radar to scan the ocean surface for an anomalous wave that might be pretty hard to discover amid the normal clutter.
In addition, these waves can move in excess of 300 mph, so they not only have to be detected and recognized, they need to be detected and recognized at a great distance for the warnings to be effective.
There are some indicators that should warn sunbathers that they are in danger, but I don’t know how much lead time they provide. For example, the oncoming wave tends to draw water to it, causing the water to recede from the beach at a distance far below that of low tide. However, if that does not happen until the wave is even 20 miles out, that gives the people on the beach a mere 4 minutes to recognize the situation and then act on it. If it does not happen until the wave is even closer, that shortens the warning even more.
The best bet would probably to watch weather buoys sensing a surge beneath them, but I do not know if we are capable of distinguishing a tsunami surge from the wake of a supertanker. (Of course, with 20/20 hindsight, using a computer to analyze all buoy readings and plotting a wave front might be useful. I also do not know that India, Burma, Thailand, Malaysia, and Indonesia have quite as many weather buoys off shore as the U.S. does.)
The second best (and more easily accomplished) methd is to have seismologists immediately report any strong underwater events and have the endangered shorelines warned to evacuate. We have actually accomplished that on a couple of occasions in the Northern Pacific–although not perfectly.
With this latest earthquake and tsunami, I have no idea how much warning was given, if any. I would imagine that getting the warning out to every possible place that may get hit with a particular tsunami is somewhat impossible.
According to the news here, there is such a system in the Pacific, but not the Indian ocean. The time difference between the earthquake and the tsunami hitting the Indian and Sri Lankan coasts was up to two hours, so they should have been able to warn the governments further away; alas they didn’t. Such a warning should be triggered by any major undersea seismic event, not specifically the observation of a travelling wave.
But would listening to broadcast radio be that rare in places like India and Sri Lanka, at least in the more urbanized areas? Given more than an hour between the wave hitting Sumatra and the wave hitting e.g. India I assume a few telephone calls between governments and from governments to radio stations ought to have saved thousands in the countries that were not hit first.
As far as “getting the word out” a system of sirens have been deployed around nuclear power plants to advise the public if an event has occurred. Simple and relatively inexpensive.
From what I heard, the USGS knew about it and tried to contact people about to be struck, but they just couldn’t reach people in time. Tragic that in this day of communication, some countries still don’t have emergency-broadcast type information like the US. Hopefully they will soon and similar tragedies can be avoided.
It’s a matter of spending priorities. Tsunamis are fairly rare in the Indian Ocean, so it doesn’t make sense to spend money on an alert system there when there are other, more common disasters that can be alleviated with that money.
The USGS said they had no contact information AT ALL. Time wasn’t an issue. Either someone in the US government failed to give the USGS that contact info, or these countries never provided it. Although I’d tend to suspect the latter. Why wouldn’t these countries have contacted the USGS to run some emergency alert drills, to make sure that both sides were prepared for such a seismic event?
You don’t need a fancy siren on every 100 yards of seashore.
A call to radio and television stations could have helped. If the stations immediately broadcast a warning, at least some people could have been saved.
But then again, which stations do you call? Perhaps the national governments of the nations involved could have gotten the message through to broadcasters if they had been warned.
And whatever happend to Ham radio? Or how about the internet? (yes I know the impoverished in this region don’t have internet access, but the broadcast outlets do, and the poor people (at least some) have radios).
Coastal regions in the Bay of Bengal and in the greater Indian Ocean are well prepared for cyclones which occur with some regularity every year. Warnings systems are in place and locals in these areas know what to expect and therefore take appropriate action, even without official warnings. ALso, Cyclones tend to build up gradually, and there are plenty of visual warning signs that one is about to hit a region.
In contrast, tsunamis are an unknown occurence in the Bay of Bengal. There are no visual warnings signs which locals can recognise and act on with rapidity. The vast majority of coastal inhabitants in this region are fishing communities - completely dependant on the sea, largely uneducated and not entirely well connected (wrt lines of communication) with relevant authorities. And even if they were, I seriously doubt the efficacy of a warning saying “Get out! Tsunami headed your way!” - how many of these people would even react to it? A forced evacuation on a scale of this kind is impossible in such short notice.
I’m not certain, but I’d guess the above also applies to islands further west of the the Indian sub-continent. I’m curious about whether even with warnings from affected countries, was it possible to predict that even these areas would be hit with such tremendous force?
Incidentally, I don’t know how aware governments in this region are that the USGS can/does provide training or drills to deal with such natural disasters.
Many of the people killed in India were fishers at sea. There would be no way to warn them.
India is a lot poorer than people realize. The government can’t even provide clean water, much less systems warning against rare occurances. It’s hard enough for them to manage everyday life, much less prepare for anything extraordinary. A family’s pocessions might include a string cot, a couple of pieces of cookware, and food for the next day or two. Radios, television and the Internet are out there, but not in the villages of fishermen. Roads in remote areas are trecherous and it could take hours to go short distances. Those that did have access to information would probably be more likely to flee than to run down to the shore to share the information.