It has been six years since the devastating Earthquake that rocked Indonesia on Boxing Day of 2004, but in that time scientists have not been idle. The German-Indonesian Tsunami Early Warning System for the Indian Ocean, tidily known as GITEWS, has been completed and will end on the 31 of March before being handed over to be run entirely by Indonesia.
“The innovative technical approach of GITEWS is based on a combination of different sensors, whose central element is a fast and precise detection and analysis of earthquakes, supported by GPS measurements,” says Professor Reinhard Hüttl, Scientific Director of the GFZ German Research Centre for Geosciences. “The GFZ-developed evaluation of Seismology via the SeisComP3 system proved to be so fast and reliable that it has now been installed in over 40 countries.”
The system is made up of seismometers, GPS stations, tide gauges and buoy systems, numbering some 300 stations throughout Indonesia which provide vital data within 5 minutes of a submarine earthquake event which then leads to a situation map providing the appropriate levels of warning for those locales likely to be affected by a tsunami.
However a tsunami warning system has its limitations, as was shown on the 25th of October, 2010, which saw the Mentawai quake cause a tsunami which ran over the top of the Pagai islands in the Sunda Arc at around about the same time the warning reached the region. Some 4 minutes and 46 seconds after the quake, the first waves arrived and took some 500 lives, just under the average time for a tsunami warning to be issued.
For the main island of Sumatra, including large cities like Padang and Bengkulu, there was some 50 minutes before the arrival of the first waves, but not all islands are so far away or protected. Sadly, the Pagai islands acted as a wonderful natural barrier to the waves, inhabitants be damned.
Nevertheless, experts are calling the warning system functional and effective, and since September of 2007, four tsunami events have been detected and warnings issued.
But warnings are not all that is necessary in the event of a tsunami. Well prepared evacuation plans in the wake of an earthquake and in fear of a tsunami are necessities, and that will only come with training and time.
Source: Heimholtz Centre Potsdam
Image Source: David Rydevik