2 Decades On: Strides in Warning Systems

In the realm of disaster management, India stands tall as a global leader, thanks to its state-of-the-art Tsunami Early Warning System (TEWS) established in the wake of the devastating Indian Ocean tsunami that crashed ashore two decades ago to this day.

- PRAVEEN SAKALYA

The tsunami of December 26, 2004, which claimed over 230,000 lives across 14 countries, served as a wake-up call for the global community. India, with its vast coastline stretching over 7,500 km, bore significant losses. In response, the government established the Indian Tsunami Early Warning Centre under the Indian National Centre for Ocean Information Services in Hyderabad. Operational since 2007, this centre is now a cornerstone of India's disaster preparedness infrastructure.

The Indian TEWS is a complex network of seismic sensors, deep-ocean pressure recorders, wave rider buoys, tide gauges, and satellite-based communication systems. It operates by detecting undersea earthquakes in real-time, analysing their potential to generate tsunamis, and disseminating alerts to vulnerable regions.

It employs a four-step approach:

1. A network of seismic stations continuously monitors tectonic activity in the Indian Ocean and beyond.

2. Advanced computer models simulate tsunami propagation and predict the likely impact on coastal areas.

3. Many instruments like wave rider buoys, bottom pressure recorders and tide gauges are installed in the Indian Ocean to monitor the trajectory of tsunami and collect wave parameters associated with it.

4. Alerts are rapidly communicated to disaster management authorities and the public through SMS, emails, television, radio, and social media.