NEW DELHI: Abnormal increase in lightning accounts for deaths than any other natural calamity and Meghalaya has become one of the worst-hit states along with neighbouirng Assam, West Bengal and Bangaldesh in the entire Indian sub-continent, studies have shown. And the situation could turn worse.
A study published in the International Journal of Climatology states that during the pre-monsoon season, the frequency of lightning is quite significant in the North East due to the interaction of moisture-laden wind with the complex topography of the region. The Meghalaya plateau and foothills of Patkai hill range, in particular, experience severe lightning, it added.
But the situation might turn worse as most scientists believe that with the increase in global temperature, the intensity of thunderstorms and lightning will increase in this part of the sub-continent.
The thundercloud formation takes place because of excess heat over Bangladesh resulting in thunder-bolts and lightning, particularly in the regions high number of water bodies.
The wind convergence results in an active convection which is the upward movement of warm and moist air. The subsequent instability results in widespread precipitation with chances of thunder-storms accom-panied by lightning.
While some districts of Assam and Meghalaya have been partially affected, the worst affected has been in Garo Hills. A study of the Indian Institute of Tropical Meteorology finds almost same result attributed to space time variation of lightning activity over Northeast India. The geographical location of Megha-laya, Assam, West Bengal and Bangladesh with the Himalayas in the north, the Bay of Bengal in the south, as well as the Indian and Arabian Oceans in surrounding areas, is adding to the rise of thunderstorms.
It is to be noted that Northeast India, parts of West Bengal together with Bangladesh, is one of the most thunderstorm-prone regions in the world. This was found by Tetsuya Fujita of the University of Chicago in 1973. Most lightning deaths and injuries occur when people are caught outdoors in the pre-monsoon and post -monsoon months towards the end of the day. A majority of the victims are the lone bread earners of their families and many of them are farmers since they have to remain in the field most of the time.
The data of the National Crime Records Bureau (NCRB) says lightning kills more people in India than any other natural calamity. According to a 2014 NCRB report, out of 20,201 accidental deaths attributable to natural causes, 12.8 per cent were due to lightning strike and in Bangladesh the lighting strike death toll is just unbelievable.
The entire Bay of Bengal, a part of Assam, Meghalaya and West Bengal are prone to lightning because of its complex topography. Studies have showed thunderstorms are very frequent during the pre-monsoon season in Northeastern India and Bangladesh.
They are especially distinctive by their nature and severity compared to other thunderstorms, which occur over some other regions or during some other seasons. While severe thunderstorms can develop at any time of the year, over half of the severe thunderstorm events occurred in the region during March, April and May, peaking during the latter months.
A secondary peak in severe thunderstorm events occurs in September, and is likely due to the impact of tropical cyclones or their remnants flowing from the warm waters of the Bay of Bengal. The data compiled by the ICRC on the occurrence of severe thunderstorm incidents show that they are first seen on an isolated day in the month of February under the influence of a western disturbance, and it becomes a familiar feature during the hot afternoons of April to May to early morning hours of the next days.
In general, severe thunderstorm impacts like loss of life and injury, loss of livelihood and damage to infrastructure are significantly more on impoverished and vulnerable rural population. Lighting casualties are increasing because of lack of awareness among people.
It was found that many illiterate people still believe lighting as well as thunderstorm to be a supernatural phenomenon or God’s fury. Awareness is very important to reduce the toll and its harmful impact, the study added.
