GPS Helps Tsunami Warning

Scientists say they have found a way faster and more accurate in the tsunami early warning system.
German research team said, the satellite-based GPS position can offer detailed information on tsunami events within a few minutes after the earthquake occurred.
They believe that technology can fix the signal issues when the tsunami struck Japan in 2011.
The results of this study have been published in Natural Hazards and Earth Systems Sciences.
When an earthquake occurs under the sea, with the power that can generate the tsunami, every second counts.
Shifting tectonic plates can produce a giant wall of water that can be advanced to the mainland in a minute, thus giving little time for evacuation.

Accurate measurement
Early warning systems to current uses data seismology, which measures the energy waves and vibrations caused by the movement of the earth.
But in the early days when the earthquake occurred, the system is not always reliable.
Currently, a team of research center GFZ German Research Centre for Geosciences said the satellite navigation technology can cover the weaknesses.
GPS sensors, which are placed around the coastline in countries vulnerable tsunami, can perform very precise measurements of the vibration of water when the ocean floor shifted.
Lead researcher Dr Andreas Hoechner explains: "In the case of the earthquake subduction, one plate under the other plate".
"It is measured by the drift. Changes in this formation occurs largely at the source, but the coastal areas will also be affected. Useful where a GPS."
He said the GPS information can be used to trace the source of the earthquake magnitude scale and calculate.
"Then you can then predict tsunami wave and see how high they cause, the more accurate."
This process he said would take a matter of minutes, which will allow early warning can be issued more quickly.
Dissemination of warning
In the case of the tsunami in 2011 that killed 16,000 people in Japan, the technology can make a radical difference.
Although the Japan Meteorological Agency issued a warning three minutes after the quake, but it underestimated the scale of the disaster scale.
When it shows that the quake was magnitude 7.9, but in fact 30 times more powerful.
By looking at the data collected GPS stations in Japan - which at the time was not used to measure earthquakes - the researchers calculated that this would provide a more accurate estimate within three minutes.
A number of countries are now installing the GPS network, including Chile and the United States.
However, Dr Hoechner said, represents an advance warning system that has accurate, but the ideal evacuation plan is also important.
He said: "One thing is to have the technology to realize where the earthquake and tsunami will happen. But equally important to spread the warning."
"You have to have the infrastructure to transmit this information to the residents, and residents should be prepared to know what to do."