Managing disaster

DISASTERS can take any form - some are sudden, some come with warning, some are more or less well predicted. Large countries with a long coastline and not stable geologically - like India and China - are prone to various kinds of disasters. Areas considered stable from the point of view of, say an earthquake, are now being reviewed with better tools. The Lathur earthquake in Maharashtra is an example. Since then, various regions have been classified as most stable, not stable and least stable. Only Tamil Nadu, Karnataka and southern Andhra Pradesh are highly stable, whereas the North, i.e. the Himalayan region and the North Eastern areas are the least stable and earthquake prone. Earthquakes are always sudden, though scientists say some amount of monitoring could enable us to predict them.

Floods and cyclones are not so sudden, they give some warning. The effects can be reduced though not avoided fully. There are other types of disasters, such as drought and the spread of unusual diseases. With careful monitoring timely action and preparedness, relief can be administered.

Most of the time the tendency is to ignore the signals that may come early, as happened recently in Orissa. It was the rarest of mega cyclones in the last century, the effects lasting for long. This cyclone could have been monitored more carefully with all the tools and techniques we have at our disposal and its effects mitigated. China and the United States too have had serious multi-disasters, but they are always better prepared than we are, and recovery too is well planned.

Remote Sensing, geographical information system (G.I.S.), use of global positioning system (G.P.S.) are all effective techniques for monitoring disasters.

There are several restrictions on the use of space and airborne data. Delegation of power to approve movement of people to safe places in an emergency is essential. Further integrating optical, IR and microwave is necessary for proper evaluation.

Combination of RS with GIS.

Combination of computer processing, extraction and analysis with expert experience.

Combination of RS analysis with ground truth.

Development of complete procedure of emergency responses

The response to floods is different from the response to earthquakes. In the case of drought assessment of damage caused to crops and non availability of drinking water which is pollution free should be quick.

Precautionary measures were not taken in time to combat the disaster in Orissa. The authorities failed to monitor the cyclone effectively. The entire coastal region had to suffer for three continuous days. Seven districts were badly affected, some 25,000 people were either killed or missing, 10 million people were rendered homeless, huge amounts of food grain and livestock were lost.

All this occurred on October 29 last year. The optical satellite pictures could not be used because for the next few days the entire area was cloudy. Some information could be got only on November 2 and 3 from the Internet.

The lesson to be learnt is we have to be prepared all the time. Strict operational procedures along with responsibilities and authority should be prepared, documented and made known in such areas. Such disasters cannot be prevented, but with proper and timely monitoring, relief measures could certainly be taken. We, therefore, have to shift our focus from locating problems and concentrate on solution to such problems, in case of need.

Similarly, floods, specifically in Assam, is almost an annual occurrence. The Central Government and the State administration may have set up numerous committees and task forces, a workable disaster management programme does not seem to have been even thought of.

One reason could be the terrain may not be amenable. The Department of Space had submitted a report on integrating space- based systems and services following the Brahmaputra floods in 1988. Similar programmes may have to be evolved in other flood prone areas. The report is fairly comprehensive in its concept, but how far it can be effectively implemented will depend upon a coordinated effort of the government, non-government organisations and the local people.

Coming to the Lattur earthquake, many people, including scientists and geologists, made many statements as to what was the cause and most of them were contradictory. Hence the need for coordination.

Drought is another kind of natural disaster, which can cause slow and continued suffering to a large number of people. This may be due to lack of rainfall, or due to shortage of other sources of water, like groundwater. We do not seem to have a detailed plan of action to manage when there is excess water due to heavy precipitation, because rainfall in our country occurs rather heavily for a small period of time, say a month or so annually. We have always been talking seriously about rain water harvesting, artificial recharge of groundwater etc., but all this preaching has not led us to simple and practical measures by which run off due to heavy precipitation could be reduced, if not prevented totally, to reduce effects of drought.

There are many other disasters - volcanic eruption, landslips, crop pests and diseases, forest fires and epidemics due to poor sanitary condition. To combat all these disaster monitoring and assessment is very important.

L.R.A. NARAYAN

Send this article to Friends by E-Mail

Section  : Science & Tech
Previous : Strength of the soil