Seismologists have created an algorithm that could one day help give coastal cities early warning of incoming tsunamis.
By studying plate tectonics in the Japan Trench, researchers from the Australian National University developed a system that can recreate the movements of a typical tsunami to determine its threat level.
Called the Time Reverse Imaging Method, the system takes real-time data from ocean sensors and uses this information to recreate what the tsunami looked like when it was 'born'.
Current tsunami warning systems rely on region-specific scenarios based on previous patterns in that area.
This is because scientists use sensors in the ocean that detect abnormal movements, but they can't make accurate projections of how much water will hit a coast, and how hard. If a real tsunami doesn't match any of the known scenarios, it results in significant loss of life.
To build the algorithm, lead author Jan Dettmer and his team studied information captured by sensors on the Pacific Ocean floor. In particular, they gathered data from Tohoku-Oki earthquake and tsunami from 11 March 2011.
Dettmer took the information from the 2011 event and used it to go 'back in time' mathematically, calculating what the tsunami looked like when it first started.
In order to predict its course, researchers studied the initial sea surface displacement – or what the wave looked like when it first started.
Once the team had the information from the beginning of the tsunami, it added it to the sensor data and projected what the tsunami would look like once it hit land. By checking his results against this event in 2011, Dettmer was able to hone his algorithm.
The plan is to test his method on other recorded earthquakes and fine-tune the technology until it is ready for implementation, which he said could be in less than five years. Tsunamis kill an average of 8,000 people every year, according to the United Nations Office for Disaster Risk Reduction.
Once scientists have the tsunami source pinpointed, they can use it to make better predictions about what will happen once the waves reach shore. This new method is fast enough to compete with existing algorithms but much more accurate.
"[The Time Reverse Imaging Method] is not based on some guess, it's based on real-time information," said Dettmer. "This method would improve accuracy without sacrificing speed. Once the earthquake happens, then we have minutes."
"This is a step forward. This research can be part of the next generation of tsunami warning systems that are based on real time information."
Dettmer and his colleagues have been speaking about their tsunami-tracking algorithm at a meeting of the Acoustical Society of America in Salt Lake City.
This article was originally published by WIRED UK
