jump to navigation

TSUNAMI WARNING December 28, 2004

Posted by wmmbb in Natural Environment.

I was puzzled by the general lack of warning of the Tsunami that devastated countries to our immediate north. The explanation, as far as I can tell, is that after the triggering event, in this case an underwater earthquake measured at almost 9 on the 10 point Richter Scale, the waves travel at a speed of a jumbo jet with a wavelength of up to 100 km, and build up to wave heights of 10, 20 and 30 metres when they enter the shallow water along coastlines.

Further information is contained here and here.

One has to assume that the ability to forecast underwater earthquakes is severely limited.

Such are the dimensions of this tragedy that it defies my imagination.

Since several countries are involved, coordination of the relief and assistance will be essential.

UPDATE: 28/12/2004

There are international warning systems, but India and Sri Lanka among the countires affected, were not part of the international system, according to this report.

More information explaining the lack of early warning systems is suggested in this Reuters report published by the NZ Herald.

UPDATE: 02/01/2005

This article, in The Independent, by the UK government’s chief scientific adviser is worth reading. Warning systems are necessary:

In the Pacific, as we were reminded last week, early warning communication cascade systems were brought into operation following earthquakes in Chile in 1960 and in Alaska in 1964, and this has markedly reduced the number of deaths as a result of tsunamis. The procedure is not complicated. It doesn’t need to be. Emergency managers are deputed to pass word to coastal communities to move inland and climb to a certain height above sea level. Similarly in Bangladesh, the impact of cyclones has been reduced simply by government employees on bicycles blowing whistles to send people to shelters. What is important is that there is a system.

In the case of the Sumatran earthquake, though, there was no system. Geophysicists did pick up the signals from the quake and rapidly locate it, determine its magnitude and estimate its impacts, but those who made frantic attempts to communicate with authorities achieved little. And nobody can pretend that the world was well prepared for what happened last weekend when those responsible for monitoring volcanic activity in the Pacific – who had picked up the rumblings from the Indian Ocean – could excuse themselves so blithely. One told Radio 4 that it was “not my job” to pass on word of what he had picked up, incredulous that anyone should think it might have been. It probably wasn’t his job, but it should have been someone’s. Reports that an Indian Ocean system are to be developed are obviously welcome.

UPDATE: 02/01/2005

The NZ Herald seems to be following up on the story relating to the lack of warning. It reports that Indian Newspapers are now on the case.

The human tragedy, made up of many individual tragedies, is beyond my comprhension or imagination to deal with. Regardless, let me remember, it is very real.

UPDATE: 16 January 2005

There is, according to this report in The Independent, evidence of a stuff up:

Scientists at the Tsunami Warning Centre in Hawaii – who have complained about being unable to find telephone numbers to alert the countries in peril – did not use an existing rapid telecommunications system set up to get warnings around the world almost instantly because the bureaucratic arrangements were not in place.

Still the thinking of the Indian Ocean governments seems to me to have been wrong-headed. Surely, if an event has a probability, given the geological circumstances of the area, and given that it has not occurred for 100 years, surely that makes some form of event, and the need for early warning, more likely, not less likely. Nobody can ride on luck for ever. But I suppose that depends on the assigned probability.



No comments yet — be the first.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: