India should read tsunamis right

A few major tsunamis have hit the Indian coastal region. The first available record is from the Madras Port Trust. The eruption of the Krakatoa volcano in Indonesia in August 1883 had its impact on the region with the height of the tsunami estimated at about 2 m. Earthquakes on January 4, 1907, in Indonesia and on June 26, 1941, in the Andamans, also gave rise to tsunamis of about 1m in height. An earthquake on November 27, 1945, located about 100 km south of Karachi in the Arabian Sea, also generated a tsunami.

Given this, it is clear that the phenomenon of the tsunami is not new to India. During the geo-technical investigation period for the Koodamkulam Nuclear Power Plant, this writer was the only person to have observed that the site at Kanyakumari is vulnerable to tsunami damage. Some found it difficult to accept the observations. But Sunday’s tsunami was rare from the seismological point of view. Within four hours, there were ten earthquakes: four in Sumatra, six in Nicobar. Incidentally, exactly one year ago, Iran experienced the destructive Bam earthquake, which took about 30,000 lives.

Could the tsunami disaster have been mitigated? As an earthquakes researcher, I believe it could have. According to the Indian Meteorological Department (IMD), this “sea storm” could not be predicted. The statement has to be taken with a pinch of salt. First, this was no storm or cyclone, it was a tsunami. Second, no one really takes pains with predictions. The formation of a tsunami is immediate, within a few minutes of the earthquake. The average speed of the tsunami waves is about 700 to 725 km per hour. Chennai, coastal Andhra and Kolkata are located at about 1,800, 2,000 and 2,300 km from the epicentre. This means that the tsunami waves would have taken roughly about 150 to 180 minutes to reach these locations. India has weather and meteorological satellites to track the formation and movement of tsunami waves. Further, our naval ships in the Bay of Bengal or Andaman Sea must have felt and recorded these waves. They should have reported the event to the appropriate authorities. Moreover, all seismologists know what is a tsunami-genic earthquake. The World Meteorological Organization (WMO) and some UN agencies have the network to monitor tsunamis. India is a member of the WMO and could have got full cooperation in the observation and recording of tsunamis. In 1996, when I was in Australia, tsunamis were generated by an earthquake in China. The Tidal Facility Center at Adelaide immediately studied the event. After computer modelling, it was found that the height of the tsunami on the Australian coast would be negligible.

Given our scientific and communication facilities, there was a clear span of about 120 to 150 minutes to send an alert message through radio, TV and loudspeakers to vulnerable communities. Had this been done, the death toll would have been lower. An earthquake in Chile, Peru or Mexico generates tsunamis, which hit Japan, some 14,000 km away. In such cases, embassies have been known to send SOS message to their parent countries informing them of a possible disaster in the offing. It is interesting to note that in the present case, a small Island country like Seychelles had sent out an alert message and all its civil defense forces were prepared.

India needs to prepare itself better for every contingency. First, the IMD should issue a forewarning about a possible tsunami. Second, satellites should be upgraded with suitable equipment to track tsunamis. Our embassies in affected countries should be instructed to react to such developments. Further, joint or inter-country collaboration with neighbouring countries on tsunami-genic earthquakes should be undertaken.

The writer is a Pune-based research seismologist