How another tsunami will affect Kerala

Tsunami expert Professor Tad Murthy, who advised the Indian and Canadian governments in the aftermath of the 2004 Indian Ocean tsunami, has said that the deepening of certain canals in Kerala will mean some tsunami energy may affect south Kerala, if and when a tsunami strikes.

"It doesn't mean I am suggesting not to deepen the canal. Without deepening, the canal may be useless as big ships won't be able to enter the canal," Prof Murthy said.

In 2004, the southern part of Kerala was not affected by the tsunami as it was not funneled into the channel to the Bay of Bengal. The tsunami got diffracted around Sri Lanka and hit the central part of Kerala coast, Prof Murthy, who has worked for the Canadian federal government and is now a professor in the Department of Civil Engineering, University of Ottawa, explained.

Some reports in the Indian media have also quoted Prof Murthy as warning that the Sethu Samudram canal project may result in Kerala being affected 'fiercely' in the event of a tsunami in the Indian Ocean in the future.

But Prof Murthy denied this, and said, "I have no knowledge of this project and I am not directly or indirectly involved in this project."

"Also, we don't use the word fiercely. This word is used in ecological terms. I am not an environmentalist or ecologist.  I specialise in tsunami," Murthy said, adding "I have no knowledge of the Sethu Canal." 

"What I am suggesting is this: To avoid tsunami energy being funneled into the channel, India has to slightly reorient the entrance away from east to the Bay of Bengal. It could be reoriented slightly to face north or whatever -- as long as it is not facing east. That way, the chances of tsunami energy getting funneled into the channel are minimised," Prof Murthy explained. 

"If it faces East, then the tsunami energy coming from Sumatra can get funneled into the channel, whereas if you just slightly reorient the channel on the Bay of Bengal entrance, the chances of tsunami energy being funneled into the channel will be much less," he said.

When asked how easy or difficult the reorientation process is, he explained, "I am just asking to change a few bricks while building a house. It's like on a scale of 100, reorientation is like .01."

Following the 2004 tsunami, the then Canadian prime minister Paul Martin invited Murthy to join his official delegation to Sri Lanka and then to India.

"I was already in New Delhi in January 2005 as I was invited by the Indian government's Department of Science and Technology for a series of brainstorming sessions during which I made a similar suggestion about slightly reorienting the channel." 

As an example, he cited the case of Port Alberni in Vancouver Island (British Columbia).  Before the Alaska earthquake of March 1964 that destroyed the city streets in Anchorage, Kodiak waterfront, etc, a three-to-five-minute tsunami was triggered. "The biggest amplitude outside Alaska didn't happen at any open coast but it happened at Port Alberni as Tsunami energy was funneled into the Alberni inlet, or Alberni canal as many say, and it amplified what we call quarter wave resonance," Murthy said.

The same could happen in Kerala as energy could get funneled in the Sethu canal and it could amplify by quarter wave resonance, in which case south Kerala may be affected."

This problem can easily be solved, he said. "You don't have to change the channel or any of those things. Just reorient the entrance to Bay of Bengal," Murthy emphasised.

The Kerala government still consults him. He said he would be going there twice a year for three years. "We are trying to develop a supplementary warning system, to support the central government system, and I am involved and working closely with the local scientists there." 

Prof Murthy and Prof Niru Nirupma of the York University have co-edited the book Indian Ocean Tsunami that was released in December.