The Government of India is deploying deep-ocean sensors off the coast of the western state of Gujarat on the basis of research that says that earthquakes along the Himalayas could cause tsunamis in the Arabian Sea.
According to a scientist closely associated with the programme who didn’t wish to be quoted, the ministry of earth sciences, which is coordinating India’s tsunami early warning system, will deploy the sensors. The sensors are part of the deep ocean tsunami detection network. An earthquake that may trigger a tsunami will dislodge water columns and thereby change pressure levels, which are detected by these sensors. Most tsunamis are generated in the Pacific Ocean. Those in the Indian Ocean haven’t been large enough to attract the government’s attention. But ever since the tsunami of December 2004, which killed 8,850 people along India’s coast, the government is not taking any chances.
“We will need at least 20 more deep-sea buoys (which only measure the sea-surface pressure), and about 12 deep-ocean pressure sensors,” said Kapil Sibal, the minister for science and technology.
“Five of these sensors have been set up as of now (in the Bay of Bengal) and next in line are those in the Arabian Sea,” said the scientist. In 1945, a tsunami triggered by an 8.2 Ms (Richter) in the Arabian Sea, was responsible for over 4,000 deaths in India, Pakistan and Seychelles. The pressure sensors, which are linked to a satellite, are part of a system of tide gauges and seismographs—all of which will measure tide and sea levels at different points along the ocean.
All of the data will be relayed to a modelling system based at the Indian National Centre for Ocean Information Services, in Hyderabad. Based on data from the system, scientists will determine whether a particular earthquake is likely to generate a tsunami. This information will be passed on to a centre at the home ministry which will handle the actual communication process and warn people living in coastal areas or evacuate them.
India currently has an interim warning system that works in association with the Japan Meteorological Organization, and early warning systems based at Hawaii. The new system is expected to be completed by September, promises to be extremely efficient. “Once the (new) system is ready we will be able to predict a 2004-like event (tsunami) two hours in advance,” said S. Kathiroli, director, National Institute of Ocean Technology, at Chennai, which is also involved in developing the system.