London, Dec 11 : Scientists are now using lasers to measure glacial melting in Switzerland and how much ice is being lost.

Changes in a glacier's thickness are traditionally measured by wooden poles and snow shovels. But is difficult to draw conclusions about such changes, using these low cost methods.

Scientists from Zurich University are now turning to laser technology to bypass these disadvantages.

"A strongly bundled beam of light is shot from an aircraft and the time is measured that the light needs to reach the surface of the ice and bounce back to the aircraft," said Philip J? rg, a university doctoral andidate.

"From this so-called 'run time', the distance from the plane to the glacier can be precisely determined to within just a few centimetres," he added.

The laser data and the exact location and position of the aircraft give rise to a highly precise, 3-D picture of the glacier's surface, said a university release.

Earlier, Zurich University researchers carried out a corresponding campaign in October with a high-resolution laser scanner at the Findel Glacier close to Zermatt.

The surface model that was created was compared with the results of a first flight over the glacier in the year 2005 and now enables a conclusion on the changes in thickness and volume of the entire glacier. (IANS)