Lightning strikes caused due to formation of large clouds: Experts
KOLKATA: The dual effect of the recent severe cyclone Yaas— that has brought in huge quantity of water vapour to the land— and the onset of Monsoon in North Bengal resulted in huge moisture availability. Consequently, this led to the formation of large cumulonimbus cloud, which triggered the lethal lightning strikes, which claimed the lives of 27 people in the state on Monday.
"Thunderstorm accompanied by lightning is a silent killer and its accumulated death is much higher in comparison to cyclones. This is because the cyclone alert is received well in advance and people have good time in hand to take precautionary measures. In case of lightning, warning is received at such a time when there is little time left to move to a safer place. The lead time is usually one to two hours," Dr. Debasish Lohar, Professor, Department of Physics Jadavpur University and a specialist in Atmospheric Science said.
He pointed out deforestation, particularly chopping down large trees, as one of the primary reasons behind human deaths. "Lightning strikes at a height and hence has a tendency of striking big trees. So, it is always advised that no one should stand underneath a tree when there is a thunderstorm. It is also advised that lying down on the ground rather than remaining in a standing position also reduces the chance of such strikes," he added.Dr. Sutapa Chaudhuri, Head of the Department of Atmospheric Science of Calcutta University, said lightning is aggravated by the effect of pollution. "There is non-availability of any conductor in open fields so people working there are much more exposed to such strikes. In the long term, we have to curb air pollution and water pollution to stop the spate of such incidents," she added.India's first ever Annual Lightning Report (2019-20) released on December 31 last year recorded 1,771 deaths due to lightning between April 2019 and March 31. About 71 per cent of the fatalities occurred while standing under trees, 25 per cent by direct hit and 4 per cent by indirect hits.