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Should lightning still be a bolt from the blue?

Lightning strike frequency has increased due to global warming, environmental degradation, and sudden weather changes resulting in cloudbursts, cyclonic storms, and thunderstorms

Simran Sharma and Nandlal Mishra | New Delhi |

Lightning is a spectacular natural phenomenon but a deadly disaster, claiming many lives every year. According to a recent study published in Weather and Climate extremes, lightning was one of the major extreme weather events (EWEs) found from the analysis of data over the span of last 50 years. The contribution of lightning towards overall mortalities due to EWEs was the least (6.3 per cent) but it showed an alarmingly growing trend compared to other EWEs. As per the National Crime Record Bureau statistics, lightning has claimed around 46,800 human lives in the last 20 years and has emerged as the biggest natural disaster-linked killer in India.
In an unfortunate incident in July, 74 people died due to lightning in the states of Rajasthan, Uttar Pradesh, and Madhya Pradesh in just 24 hours. Not just human beings but animals also become the target of nature’s wrath. Earlier this year, the death of 18 elephants in Assam was attributed to lightning strikes, and around 300 goats and sheep in Himachal Pradesh were killed by deadly thunderbolts in June. It also affects communication and aircraft navigation systems, causes electrical power breakdown, and leads to forest fires. There have been increased instances of lightning-induced forest fires across the western USA.
Although precise location is unpredictable, lightning does show seasonality and some regions are more prone than others. A 2020 study published in Natural Hazards, says that although the lightning season is varied over different regions of the country, the most prominent seasons are pre-monsoon and monsoon based on the cloud to ground lightning data analysed over a period of 16 years (1998-2013). It is also interesting to note that even though north and north-eastern hilly states like Assam, Meghalaya and Jammu & Kashmir, receive higher lightning flashes density, the reported deaths are less due to sparse populations. Whereas states like Odisha, Maharashtra, and Madhya Pradesh suffer higher fatalities given the high population density.
Despite being such a deadly disaster, lightning does not receive enough attention from the masses and the governments. To minimise the deaths due to lightning, Lightning Resilient India Campaign was launched in 2019, a joint initiative of Climate Resilient Observing-Systems Promotion Council, National Disaster Management Authority, India Meteorological Department, Ministry of Earth Sciences and NGOs. The campaign aims to reduce lightning related human and livestock casualties by 80 per cent in three years. They have also developed comprehensive lightning map for two consecutive years. The country has been mapped as a whole and different states are mapped individually as well, to supplement the process of identification of hotspots and subsequent risk management. From the lightning density map, the maximum density seems to be around central and eastern states with Odisha receiving the highest number lightning strikes followed by Madhya Pradesh, Chhattisgarh, West Bengal and Jharkhand between April 2020 and March 2021.
The distribution of lightning deaths shows that 96 per cent of deaths occurred in rural areas compared to just 4 per cent of deaths in urban areas, which is attributed to rural livelihood pattern of working in open vulnerable spaces and lack of awareness among the rural masses. The increased lightning activity during pre-monsoon and monsoon seasons coinciding with planting of kharif crops is a likely reason for more fatalities during this time. It was also found that the areas most affected by lightning coincide with the tribal areas and therefore tribal and marginalized people become more vulnerable to lightning mortalities owing to their tin-roofed houses and land-dependent livelihoods.
Another interesting finding was that standing under a tree was reported as the primary cause in 71 per cent of the cases. This emphasises the need to dispel the long-standing myth of taking cover under a tree when lightning strikes, which proves to be extremely dangerous. But there is hope and states like Odisha have done commendably well with registering 207 deaths despite the highest number of lightning strikes during 2020-2021, while the states of Uttar Pradesh and Bihar suffered double the number of fatalities with half the number of total strikes. Odisha has been able to reduce its lightning-related fatalities with better equipment and infrastructure, proper early warning and notification systems, and public sensitization towards this issue. Odisha was able to ensure zero lightning-associated deaths during the destructive Cyclone Fani in 2019, with cyclone shelters equipped with lightning arresters.
Lightning is not yet a centrally notified disaster and only some states have included it in their state-specific disasters that creates a barrier for utilization of relief funds. Therefore, it is important to elevate the status of lightning as a centrally notified disaster to improve the scope of compensation to affected families.
Lightning strike frequency has increased due to global warming, environmental degradation, and sudden weather changes resulting in cloudbursts, cyclonic storms, and thunderstorms. Lightning influences atmospheric chemistry as it is indirectly responsible for production of tropospheric ozone – an important greenhouse gas and a pollutant. The phenomenon of lightning itself is affected by a multitude of factors including local surface temperature, temporal and spatial variation of aerosol content, moisture on earth surface, regional instabilities etc.
Long-term projections for lightning flashes have been difficult. There are conflicting studies with some showing a projected increase and some claiming a decrease in the future. A study published in PNAS in 2017 says that the destructive potential of tropical and subtropical thunderstorms under the global warming scenarios is likely to increase which may lead to increased lightning strikes. A 2021 study in Atmospheric Chemistry and Physics, also warns of a similar scenario over the Indian region with the lightning frequency rising by 10 to 25 per cent and intensity increasing by 15 to 50 per cent in extreme future conditions. The situation will likely be grimmer over the coasts. However, based on a different approach, another study published in Nature Climate Change in 2018, claims that there will be a decrease in lightning flash rate by 15 per cent by the end of this century.
Nevertheless, it is important to keep in mind that despite the uncertainty in future, the current situation is extremely grave. Lightning strikes and deaths have both been rising over the years and therefore need undivided attention. NDMA has issued comprehensive protocols and guidelines elaborating on the roles of various agencies and the steps that need to be taken to improve last-mile delivery to reduce mortalities. Additionally, IMD lightning forecasts and applications like Damini (national), Vajrapath (Andhra Pradesh) etc. provide early warnings for lightning.
New and improved technologies, equipment, guidelines, and infrastructure are available to combat this long-neglected disaster. What we need are aggressive measures by governments to ensure that the protocols don’t just remain on paper and implementation is such that the vulnerable population who are often the poorer and underprivileged, are safeguarded. Collaborative efforts by different agencies and stakeholders are the only way forward to build adaptability and resilience in the face of increasing climate extremities.