Another tsunami in the offing?

Although it has been over a decade since the 2004 tsunami struck, Kedah, especially Langkawi and Kota Kuala Muda are still at risk of being hit by another, cautions Kedah Meteorology Department director, Rosli Zakaria @ Che Kob.

He said this was due to the geographical position of the region which was adjacent to the western side of Sumatra, an area well-known for earthquake occurrences.

Langkawi, he said, was very much at risk of being hit first, based on the 2004 tsunami which saw the shorter distance between the epicentre and Pantai Cenang.

"Measuring a straight distance between the epicentre and Langkawi, we estimate it to be about 550km, but if you measure the actual distance of the tsunami waves, it is almost 1,000km," Rosli told Bernama recently.

In fact, he said, the impact of the tsunami caused by the Indian Ocean earthquake off the western coast of northern Sumatra on Dec 26, 2004 saw waves of 3.7 metres high and arrival time of three hours 15 minutes at Pantai Cenang in Langkawi, while Kuala Muda recorded waves of 3.9 metres with arrival time of four hours and 32 minutes.

The tsunami which swept across several countries in 2004, had also battered Kedah, leaving 10 people dead in Kota Kuala Muda and another in Langkawi, in its wake.

"Tsunami risk is always there because the northern and western Sumatra areas are active areas due to the convergence of two tectonic plates which are the cause of earthquakes," said Rosli.

However, he added, for the area to bear the tsunami brunt, the earthquake in the Sumatra region should exceed a magnitude 8.0 on the Richter scale.

He said at the moment, there were eight seismological stations available in the state, capable of detecting an earthquake, and eight tsunami sirens to send out early warnings.

Five of the sirens were located in Langkawi at Pantai Cenang, Padang Mat Sirat, Telaga Harbour, Kuala Teriang and Pantai Pasir Hitam while three others were at Kota Kuala Muda, Tanjung Dawai and Kuala Kedah.

Rosli said the department worked closely with other security agencies, especially in preparedness planning and mitigation, in the event of any disaster.