India’s S-Wave Early Warning System

Context:

India is developing an early-warning system for detecting destructive secondary waves (S-waves) during earthquakes to protect lives and infrastructure.

About S-Waves and Early Warning:

Earthquakes release primary waves (P-waves) and secondary waves (S-waves).
P-waves are faster and less damaging, while S-waves are slower but more destructive.
An early-warning system (EWS) detects P-waves and provides a short lead time (a few seconds) to warn about incoming S-waves.
This lead time can be used to shut down infrastructure, alert citizens, and evacuate vulnerable buildings.

India’s Initiative:

Over the next decade, India plans to deploy a national network to detect P-waves and anticipate S-waves.
The Ministry of Earth Sciences is leading this effort.
The system will include accelerometers, seismometers, and GPS devices at vulnerable locations.

Technological Integration:

Systems will incorporate real-time data, resilient construction practices, and AI for risk evaluation.
The Coalition for Disaster Resilient Infrastructure (CDRI) plays a vital role in supporting such initiatives.

Current Challenges:

Scientific prediction of exact time, location, and magnitude of earthquakes remains unresolved.
However, seismic monitoring in real time can help in assessing where and when an earthquake has occurred.

Global Example:

Japan already operates a functional earthquake early-warning system using the same principle.
India aims to emulate such systems by strengthening scientific and technical infrastructure.

India’s Vulnerability:

Around 59% of India is classified as vulnerable to earthquakes.
The Bureau of Indian Standards (BIS) classifies seismic zones from Zone II to Zone V:
- Zone V (e.g., Himalayas) is most active.
- Zone II is the least active.
Past major events:
- 2001 Bhuj earthquake (7.9 magnitude): ~12,932 deaths.
- 2005 Kangra earthquake (8.0 magnitude): ~19,800 lives lost.