Washington, Apr 3 : Scientists at the University of Nevada, Reno, are developing technology to increase the effectiveness of tsunami warning systems.

The team led by Geoffrey Blewitt of the Nevada Bureau of Mines and Geology and Seismological Laboratory have demonstrated that a large earthquake's true size can be determined within 15 minutes using Global Positioning System (GPS) data.

Researchers say the swift exchange of information, which is much faster compared to the modes of communication currently used, can be critical in determining whether an earthquake might trigger a tsunami.

"Together with a seismometer and ocean buoy data, GPS has the potential to become an important tool in improving tsunami danger assessments," said Blewitt, whose work was originally accomplished through the NASA-funded Jet Propulsion Laboratory in Pasadena, California.

"We'll always need seismology as the first level of alert for large earthquakes, and we'll need ocean buoys to actually sense the tsunami waves. But the advantage of including GPS in warning systems is that it quickly tells how much the ocean floor moved, and that information can directly set tsunami models into motion," he said.

University seismological expert John Anderson, director of the Nevada Seismological Laboratory, and one of US's foremost earthquake experts, said that people living along shorelines should always be aware that tsunamis could occur.

Together with Richard Schweickert, professor of geological sciences and engineering, Anderson has used analysis similar to that used in studying the propagation of tsunamis in oceans in determining the likelihood of a tsunami occurring at Lake Tahoe, which straddles the states of Nevada and California.

"If there is ever a strong earthquake at Lake Tahoe, for example, where the shaking is really strong for more than 10 seconds, anyone less than 50 feet above the lake level should run to higher ground as soon as the shaking stops," Anderson said.