Tsunami: Scientists say scale of destruction in Gujarat can be more than Andamans

New Delhi
12 November 2005

A team of scientists from India and abroad has estimated that
a tsunami in the Arabian Sea can cause more destruction in Gujarat than what the
December 26, 2004 tsunamis in the Indian Ocean did in Andaman and Nicobar Islands.

The reason is that the amplitude or maximum height of a tsunami (tidal wave) can be as
high as 15 metres in the Gulf of Kutch and 13 metres in the Gulf of Cambay as compared
to 11 metres in Andaman and Nicobar Islands.

A tsunami's amplitude or height is a pretty good indicator of its potential to do damage.

That there is a discernible difference between the amplitude of a normal tidal wave and
that of a tsunami can be understood from the fact that the Jarawa tribe, which survived
the December 26 tsunamis, fled to the highlands the moment they spotted the first wave.

The team arrived at this preliminary conclusion based on analytical models for the
Indian Ocean tsunami warning system. It comprised four scientists including a woman
from premier institutions or universities in India and Canada.

It is a collaborative work by Dr Tad Murty and Prof Ioan Nistor of the Department of Civil
Engineering, University of Ottawa, Canada; Prof N Nirupama of York University in
Toronto, Canada; and Prof AD Rao of the Indian Institute of Technology, Delhi.

(Dr Murty and Prof Rao were also instrumental in preparing tsunami travel time atlas,
which provides the ETA or expected time of arrival of the first wave of tsunami at
selected coastal locations so that people can be evacuated in time.)

The team has also worked on coastal inundation models, which provide information
about how high the tsunami waves will be at selected coastal locations, how far inland
the tsunami inundation will occur and the strength of the currents.

Accordingly, it is estimated that the number of coastal-inundation models needed for the
east- and west coasts of India besides Andaman and Nicobar Islands is 87. The
Andaman and Nicobar Islands will require 15 models and Gujarat, 10.

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