‘222 dead and almost 800 injured as KRAKATOA erupts triggering a tsunami in Indonesia.’ The news has been on the social media for 2 days now since Saturday night when this happened. The meteorological, climatology and Geophysical Agency (BMKG) confirmed that the tsunami was caused due to the volcanic eruption. The volcanic activity triggered an underwater landslide resulting in the tsunami.

The question here is, how did the tsunami come as a surprise? Did the systems not realize the change in the water current?? How dependable are the warning systems deployed to the task now??

Natural calamities are not just one thing. Here one thing can lead to another. A volcanic eruption can lead to a tsunami. Underwater landslides might lead to an earthquake. Two simple warm and cool currents when meet can form a tornado. We cannot control them. So what remains with us is to make a system that can predetermine the calamity. A system that will not predict but at least mark the arrival of calamities.  

 What is an early warning system??

An early warning system is a chain of information communication system. The system consists of sensors, event detectors, and decision subsystems. Together they work to forecast and signal the disturbances that might disrupt the stability of the physical world. These signals give time to response system against the disturbance and minimize the impact.

Early Warning Systems are designed for a number of calamities including floods, earthquakes, avalanches, tsunamis, tornadoes, landslides, droughts, etc.


How does EWS for Tsunami work??

The EWS for a tsunami is made up of two important components. The seismic-monitoring stations and the sea level gauges. These two components are located at various places in the world forming a network. They detect drastic changes in sea level and also detect earthquakes. This information helps scientists to predict an earth quake triggered tsunami.  

How does EWS for earthquake work??

Though there is no perfect system existing to determine an earthquake, it can be predicted. The system gathers data from a network of seismic monitoring stations. The seismic monitoring stations are nothing but locations where seismometers are located.

The seismometer is an instrument that measures ground motions. Earthquakes, explosions, and eruptions usually cause ground movement. The seismic waves help researchers to measure the intensity and know the exact location of the action.

Why do we need EWS??

EWS i.e. the Early Warning System will help reduce the impact of calamities. At the time of crises what is important is not the infrastructure of the materialistic things but human life. If a calamity is known before it happens we may not be able to zero the effects but at least reduce it. Animals have been blessed with the ability to know calamities before-hand. Humans do lack behind in some factors we must say!! EWS is the need of the hour when we have too much to lose if it came unannounced.


Calamities are easy to tackle if known previously. For this purpose, the early warning systems need to be really efficient. The EWS is not a well-developed system yet but with advancements and researches, we will definitely be able to reach the star.