topic Research

Seaquakes and the Tsunami Early Warning System

On 26 December 2004, a seaquake off the Indonesian coast caused a tsunami which devastated large areas of South East Asia. In conjunction with approximately 20 national and international partner organizations, researchers from the National Research Centre for Geosciences (GFZ) in Potsdam have worked on the development of a tsunami early warning system to provide effective protection for the population. The system was launched in November 2008. It is just one of the contributions which Germany is making within the framework of its efforts to assist states in Asia affected by the seaquake and is part of the concerted aid which has been coordinated by the UNESCO Intergovernmental Oceanographic Commission (IOC) on behalf of the UN since 2005.

The proximity of the Sunda Arc made it particularly important to establish a tsunami early warning system in Indonesia. Two continental plates meet here and are pushing underneath one another at a speed of six centimetres per year. This so-called subduction process repeatedly causes very strong earthquakes which can trigger tsunamis. As more than 90 percent of all tsunamis are caused by seaquakes, a central component of the early warning system is the quick detection and evaluation of earthquakes. Ocean measuring equipment positioned on the ocean floor, on buoys or in the form of tide gauges is used to recognize an approaching tsunami.

A new data and warning system in Jakarta receives all the information collected in real time and combines all the individual readings from the most diverse systems to form an overall picture which can be quickly interpreted, providing important information such as when the tsunami will reach the various sections of the coast or the expected height of the waves.

In the case of the Sumatra quake in 2004, the waves devastated various sections of the coast just a quarter of an hour after the seaquake. No one can evacuate a town in this short time. But pre-calculated scenarios can help the emergency services to optimize their operational planning. The early warning system is also able to estimate when the tsunami will reach more distant sections of the coast or even other countries, how strong it will be and which sections of the coast are at risk and thus have to be evacuated.

Launch in November 2008

The tsunami early warning system began operations on schedule on 11 November 2008. Responsibility will be handed over to the Indonesian side in 2010 following a two-year joint German-Indonesian operating phase.

The GITEWS is open and decentralized in its design in order to allow links with other regional and future systems. It also includes the establishment of satellite communication facilities and the development of know-how in the central warning centre, together with training courses for decision-makers and experts as well as for people responsible on-the-spot and the local population.

In addition to implementing and including existing technologies, a further focus is on research work to develop new satellite-based components of an operative early warning system.

The project has received a total of 45 million euros from the German Tsunami Aid Fund. Cooperation has also been agreed with other countries besides Indonesia: institutions from coastal states such as Kenya, Madagascar, the Maldives, Yemen, Sri Lanka and Tanzania are already partners of the GFZ; other states such as Malaysia, India and Thailand have voiced an interest in cooperation.

The Third International Conference on Early Warning - EWC III was held in Bonn in March 2006 to consider the issue of early warning systems for tsunamis and other natural disasters.

Research to develop early warning systems

Natural disasters such as the seaquake in South East Asia with well over 230,000 victims are a rare occurrence. Nevertheless, scientific data show that such catastrophes can also occur in Europe.

For example, the old quarter of Lisbon was destroyed by a tsunami in 1755. Istanbul is the world's metropolis most strongly threatened by earthquakes, after Kathmandu; and 8000 years ago, underwater landslides off the Norwegian coast caused a 20 m tidal wave in the North Sea.

Since 2007, the Federal Ministry of Education and Research has provided funding of approximately 9 million euros under its Geotechnology Programme to 11 collaborative research programmes to develop early warning systems for natural disasters such as earthquakes, tsunamis, volcanoes and landslides.