New Delhi, Nov. 14: A software method developed by Indian oceanographers to predict the movement of oil spills towards vulnerable sites along the country’s coastline will need a real oil spill incident for its validation, scientists have said.

Scientists with the ministry of earth sciences announced on Saturday that they have combined software and sea and wind data to develop an early warning system that could predict behaviour of oil spills that might occur in the seas around India.

The Sunderbans and Hooghly are among 28 sensitive spots, tourist beaches or sites of historical importance along India’s 7,500-km long coastline that face a high or moderate risk of oil spills.

The software method developed by researchers at the Integrated Coastal and Marine Area Management (ICMAM) Project in Chennai uses data on wind speed, sea currents and tide conditions to predict the movement of an oil spill.

“Within minutes, the software can tell us in which direction the oil will move,” said B. Ramamoorthy Subramanian, project director with ICMAM.

The simulation will allow scientists to pinpoint spots on the coast where the oil will flow if it is not contained.

But scientists also point out that the software method has yet to be validated — a process in which its prediction of oil movement is compared with the actual behaviour of an oil spill — to determine the accuracy of its forecasts.

“We will need a real oil spill to do this,” a senior scientist in the department of ocean development said. “Only when an oil spill occurs will we be able to compare how it moves and what our software predicts,” the scientist said.

A senior scientist associated with the project said validation using data from oil spills that have occurred near India in the past has not been possible because of “incomplete data” about the oil spill and sea conditions at the time.

Subramanian said partial validation had been done with sediments in the Gulf of Kutch region, but the behaviour of oil and sediments floating in the sea might be quite different and true validation would require a real oil spill.

“Confidence in the software’s ability to predict movement of oil spills will grow only through a validation campaign and repeated use,” the scientist said.

Ocean scientists estimate that some 500 million tonnes of crude oil carried by 3,500 tankers pass annually through the seawaters close to India. Any major oil spill in the Arabian Sea or in the Bay of Bengal is expected to lead to large-scale ecological and economic damage.

An oil spill is typically tackled through a combination of several methods — rubber floats called booms are placed in the sea to create a physical barrier to prevent the oil from moving towards the coast, or chemicals are spread out on the oil spill to disperse the oil, or the oil is skimmed from the surface of the sea.

Several spots along India’s coastline are rich in coral reefs, mangrove swamps, marine bio-diversity zones and turtle nesting grounds that could be damaged by oil spills. In addition to the 28 coastal sites at high or moderate risk, scientists have identified another 14 at low risk.

Oil spills could be caused by tanker accidents or pipeline ruptures. Last year, a 4,500-tonne oil spill occurred about 500 km west of Indira Point in the Nicobar archipelago, and Mumbai harbour experienced a 2,000-tonne oil spill. The worst oil spill near India occurred in 1993 when 40,000 tonnes of oil went into the sea between Nicobar and Sumatra.