THIRUVANATHAPURAM: While the scientific world is yet to begin their studies on the tsunami that ravaged Japan last week, scientists from the state have predicted that if a tsunami is to hit the state like the one that flattened Sumatra in 2004, the areas of Valiazhikkal, Azhikkal and Kallikad near Kayamkulam will see the highest waves of almost 5 metres. As per the simulation studies, the largest inundation will be at Valiazhikkal, with water expected to flow one kilometre into the inland.
The scientific team of N P Kurian, S S Praveen and T S S Hameed of the Centre for Earth Science Studies (CESS) conducted several simulation studies on the basis of the Makran tsunami that hit the Indian coastline in 1945, the Sumatra tsunami of 2004 and a worst case scenario where an earthquake of the same intensity of Sumatra hitting Makran area. “The Inter-governmental Panel on Climate Change (IPCC) has predicted a sea-level rise of over one metre on the Kerala coast. Couple this with tsunami, several areas on the Kerala coast become highly vulnerable,’’ said S S Praveen, who is doing tsunami modelling studies with the Cochin University of Science and Technology.
Three representative coastal sectors of Kerala were chosen for the study - the Neendakara-Thottappally region representing southern Kerala, the Munambam-Valappad representing Central Kerala and the Marad-Kannur region representing northern Kerala. Northern Kerala being closer to Makran, the Kerala coast north of Vadanapally in Thrissur, showed a higher tsunami impact with high levels of inundation and run up (temporary rise in sea-level) to the simulated Makran tsunami than the Sumatra one.
Similarly, southern Kerala, except for Thiruvananthapuram, showed higher waves and larger inundation for the Sumatra tsunami than the Makran one. A major reason for this is the flooding of the T S Canal, which overflows into the lowlands. Thirvananthapuram has a relatively higher shore level, which helps it to withstand the smashing force of water. Similarly areas of north Kerala also have cliffs that will take away the destructive power of water. The simulation for the hypothetical potentially worst case shows marginal increase in inundation along the entire Kerala coast when compared to Makran 1945 and Sumatra 2004 tsunamis. The simulation results for extreme sea-level rise scenario for hypothetical source predicts an increase in inundation of around 2 km, along the Neendakara-Thottapally stretch on comparing with Sumatra 2004 whereas in the other sectors the increase in inundation is comparatively low.
“It can be concluded that sea-level rise can definitely make pronounced increase in inundation in some of the stretches where the shore elevation is comparatively low. We have to plan tsunami mitigation measures taking the case of the hypothetically potentially worst case with extreme sea level rise scenarios,’’ said Praveen.
