"The aim is to be able to send out an alert within 10 minutes of the earthquake that sets off the giant waves and to save lives," said Joern Lauterjung of Germany's national research centre for geoscience (GFZ) in Potsdam outside Berlin.
The offer to develop a complex quake measuring system with sensors on land and the seabed relaying information via satellite to remote computers, was made three weeks after the tsunami killed about 220 000 people along the Indian Ocean shoreline on December 26, 2004.
The government of Indonesia, which bore the brunt of the killer waves, immediately accepted and 120 German experts went to work on a project named the German Contribution to the Tsunami Early Warning System for the Indian Ocean (GITEWS).
Three years later, the mission is almost accomplished and the researchers hope to have the system up and running in November 2008.
Since early 2005, the German team has worked with Indonesian, American and Japanese crews on setting up 160 seismic measuring stations on land and anchoring 23 sensors to the ocean bed.
The seabed sensors are vital to the system's success because the instruments on land cannot give scientists a picture of how the earth's plates have been deformed below the sea by a quake.
"The land sensors are not enough because they do not enable us to know how an earthquake has damaged the seabed. It is only if there is a vertical deformation that the seism will be followed by a tsunami," Lauterjung said.
In 2004, he explained, the strongest earthquake ever recorded in this region pushed the earth's crust upwards by 15 centimetres (six inches) with a violent jolt that triggered the tsunami.
The underwater sensors are cast into the waves attached to weights to make them sink more than five kilometres (three miles) to the ocean floor.
They can measure the pressure of the water mass above them, and therefore its height. This means that any sudden variation in sea level is detected and used to predict the formation of giant waves.
The sensors carry out measurements every 15 seconds and relay the information to a buoy which sends the information to Jakarta via satellite.
If a quake is detected and at the same time the seabed monitors measure abnormal water pressure, another complex part of the warning system kicks in, as the GFZ's technology seeks to predict where and when the tsunami will strike the coast.
"These calculations unfortunately take a long time because, since the seabed is not even, the range of variables to be taken into account is vast. We have therefore developed models of potential trajectories to save our computers time," Lauterjung said.
The system had what his team described as a "baptism of fire" in September when an 8.4-magnitude earthquake struck off the west coast of Indonesia's Sumatra island. It measured the size and location of the seism within a record five minutes.
This enabled the scientists at Potsdam to raise the alert to Indonesian authorities more than 10 minutes earlier than the Pacific Tsunami Warning Centre in Hawaii.
It is big step forward in a field where mere minutes can mean the difference between live and death for people in the path of a tsunami, the GFZ's Joachim Zschau said.
It takes 10 to 20 minutes from the time a seabed earthquake happens for a tsunami to hit the coast.
"The difference in time is really important because the challenge is to warn people away from the coastline within minutes," Zschau said.
"If you have the information this soon after the earthquake hits, you could get the information to hotels and villages and avert a potential disaster."
Ultimately, the researchers said, common sense could prove as important in the rush to save lives as sophisticated technology.
"There are very simple things which we need to convey to the population in risk areas -- for example that shortly before the tsunami strikes, the ocean recedes, and that this is the moment to run," Lauterjung said.