Undersea Internet cables 'could detect tsunamis'

An Indian-origin researcher has proposed waht he claims is a cheaper and capable way of detecting an approaching tsunami,by the use of undersea Internet cables to sense its eletric field.


Tsnami waves,like the ones that killed over 200,000 people in Indian Ocean in 2004,create an electric field as they form.This field can be suspected by the help of a network of underwater sensors which would be too expensive to build.
However,only five countries own such sensor arrays-the U.S.(of course),Australia,Indonesia,Chile and Thailand-partly because of the installation prices.


Now Manoj Nair and his team at the National Oceanic and Atmospheric Administration in the U.S.,have proposed a cheaper way of using the undersea telecommunications cables to detect tsunami's electric field,the 'New Scientist' reported.


The electric filed is created as electrically charged salts in seawater pass through the Earth’s magnetic field.


Computer modelling by Nair’s team shows that the electric field generated by the tsunami that struck south-east Asia in 2004 induced voltages of up to 500 millivolts. Their calculations show this is big enough to be detected by volt-meters placed at the end of the fibre-optic and copper cables that carpet the floor of the Indian Ocean.