Had an India Meteorological Department project, initiated in 2012, been in place, the tragic incidents lightning strikes killing nearly 100 people during monsoon thunderstorms in Bihar and Uttar Pradesh could have been averted. The now stalled project was to install lightning detectors in vulnerable regions.
Manish Ranalkar, one of the scientists involved in the stalled IMD project, told The Hindu that the proposed project remained incomplete as only one qualified supplier was available for this technology, which is patented by the Finnish firm Vaisala. Since government tender processes require competitive bidding, the project was stalled. The project was part of the “nowcasting” programme of the IMD in which meteorologists deliver instant updates on current weather indices such as storms and lightning obtained by extrapolating for a period of 0 to 6 hours ahead of the occurrence of the phenomenon.
Increasing thunderstorm frequency
A 2007 study on thunderstorm climatology over India published in the IMD’s quarterly journal Mausam shows higher annual frequency of thunderstorm of 100-120 days as compared to 80-100 days given by earlier studies. What we can deduce from that is that the frequency of thunderstorm occurrence has increased by about 25 per cent over a 15-year period as indicated in the paper. Increased thunderstorm activity only means increased incidents of lightning strikes, calling for preventive measures.
Experts at Vaisala cited studies to show that major loss of life due to lightning occurred often during agricultural activities. Those involved in labour-intensive agriculture, a day-time activity, when lightning is most common, are the most vulnerable. Most of the deaths reported in India also were of farmers. So while avoiding outdoor exposure during thunderstorm conditions could keep vulnerable populations safe, this alone cannot prevent deaths from lightning strikes happening as people could get caught in it unsuspectingly.
Technology to the rescue
“Widespread availability of substantial buildings with grounded wiring and plumbing that surrounds people inside with a Faraday-cage effect, and the widespread availability of lightning-safe fully enclosed metal-topped vehicles can help avert deaths if they can be accessed easily,” Brooke Pearson, head of product area, lightning, at Vaisala said.
A more foolproof method would be to install lightning detectors that can warn people in advance. The technology relies on ground-based and satellite-based lightning locating systems, which are capable of reporting a variety of processes and characteristics associated with lightning flashes. A network of sensors detect and measure electromagnetic emissions generated by lightning, and a central processor analyses these remote measurements to geo-locate and characterise individual lightning events to determine the location, intensity, and type of lightning, and track the movement of thunderstorm cells for lightning warning applications.
“Such sensors have already been installed over 90 precision lightning detection networks in 45 countries, across the world, for various applications including for lightning warnings, which can be distributed via public broadcasting such as radio and television and by modern communications via the internet and by mobile phones,” Mr. Pearson said.
Mr. Ranalkar, the IMD scientist said, “In the cloud, electrical discharges start to build up much before the lightning strike becomes visible to the human eye and with the help of technology it is possible to detect a major lightning strike at least half an hour to one hour before it hits,”.
Unfortunately government procurement guidelines are stopping India’s official forecaster from adopting the technology.
