WHILE floods and cyclones dominate the national conversation on climate risk, a quieter killer claims hundreds of lives every year. Science now confirms it is getting worse, and we are not ready. On the afternoon of April 27, a line of Kal Boishakhi, seasonal storms, swept across Bangladesh with little warning. By the time the sky cleared, at least fourteen people were dead: farmers caught in open paddy fields, fishermen on exposed waters, and children running for shelter that never came. It was, by any measure of routine tragedy in this country, an unremarkable week.
Bangladesh has become so accustomed to death by lightning that we have stopped demanding answers. We count the bodies, we mourn, and we wait for the next storm. But the science is now unambiguous: the storms are growing stronger, more frequent, and more lethal. This is not fate. This is climate change.
Physics of a warming sky
TO UNDERSTAND why lightning is intensifying, one must first understand what generates a thunderstorm. The key variable is convective available potential energy, or CAPE, which is the stored atmospheric energy that drives warm, moisture-laden air rapidly upward. As that air rises, it cools, condenses, and forms towering cumulonimbus clouds. Inside those clouds, collisions between ice crystals, supercooled water droplets, and churning air masses build up massive electrical charges. The result, discharged in milliseconds, is lightning.
Climate change supercharges every step of this process. A warmer atmosphere holds more water vapour, approximately seven per cent, more for every degree Celsius of warming, following a well-established thermodynamic relationship. More moisture means more fuel for convection, which means more energetic storms. A landmark 2014 study published in Science by Romps and colleagues quantified this relationship with sobering precision. For every one degree Celsius of global warming, lightning frequency increases by approximately twelve per cent. Given that Bangladesh’s surface temperatures are rising faster than the global mean, this scaling factor is not merely an abstraction. It is a local emergency playing out in our fields and rivers every April.
The most comprehensive modelling applied specifically to Bangladesh confirms this trajectory. A 2025 study published in Natural Hazards, using CMIP5 climate projections under a high-emissions scenario, found that CAPE values over Bangladesh could increase by as much as forty-five per cent during the pre-monsoon season of March through May. Those are the very months when agricultural labour peaks and when Kal Baishakhi storms are most active. By the end of this century, thunderstorm frequency could rise by thirty-nine per cent in the pre-monsoon, sixty-eight per cent in the post-monsoon, and thirty-five per cent during the monsoon itself. At some weather stations, annual increases of sixty per cent are projected. These are not worst-case outliers. They are mid-range estimates from peer-reviewed science journals, and they should be treated as planning assumptions by every ministry with a stake in public safety.
Transboundary pollution
TEMPERATURE alone does not explain everything, and I think this part of the story deserves far more public attention than it currently receives. Research published in 2025, drawing on work by Dewan and colleagues and reported by Mongabay, identified a troubling amplifier: aerosol pollution drifting eastward from northern and western India. During April and May, concentrations of dust particles are eighty-eight per cent higher than baseline, and sulphate aerosols run fifty-one per cent above average. These particles do not merely dirty the air; they fundamentally alter the microphysics of cloud formation.
In a polluted cloud, water droplets are smaller and more numerous because each aerosol particle acts as a condensation nucleus, competing for available moisture. Smaller droplets are carried higher into the atmosphere before freezing, extending the zone of charge separation within the cloud and intensifying the electrical gradient. The result is a cloud that is both more energetic and more prone to discharge lightning. This aerosol effect coincides almost perfectly with the peak of Bangladesh’s lightning mortality season, an alignment that researchers now argue is causal rather than coincidental. We are, in part, being struck by our neighbours’ pollution. That is a fact that deserves a diplomatic conversation, not just a scientific paper.
Why are so many people dying?
THE intensification of storms explains the rising frequency of lightning, but it does not by itself explain why Bangladesh buries so many of its dead from this cause while larger countries do not. The United States, with a population more than twice as large and facing its own severe lightning seasons, records fewer than twenty deaths per year. Bangladesh records about three hundred annually. This disparity is not written in the clouds. It is written in policy, infrastructure, and the particular vulnerabilities of rural poverty.
The most exposed are agricultural labourers working in open fields during planting and harvesting seasons that coincide precisely with the pre-monsoon storm peak. There is no lightning shelter to run to, no real-time alert on a government device, no employer accountability for keeping workers outdoors during a storm warning. The deforestation of rural Bangladesh has compounded the danger in a paradoxical way: the tall trees that once absorbed strikes and provided some natural protection are gone, leaving human beings as the tallest objects in a flat and open landscape.
The government formally recognised lightning as a natural disaster in 2016, a decade after scientists and activists had been calling for exactly that designation. Recognition, however, has not translated into the systematic response that official classification implies. Lightning shelters remain scarce. Community-level early warning systems are inadequately funded. Awareness campaigns of the kind that teach people not to stand under isolated trees, to exit water bodies quickly, and to avoid metal objects during a storm reach urban audiences far more reliably than the rural communities most at risk. The director general of the Department of Disaster Management has himself acknowledged that global warming, environmental changes, and living patterns all contribute to the rising death toll. The diagnosis is correct. The prescription has been unconscionably slow to follow.
What must be done, and soon
THE scientific consensus leaves little room for complacency or delay. Under the high-emissions scenario that current global policy trajectories make uncomfortably plausible, Bangladesh faces a future of substantially more frequent and powerful thunderstorms. Adaptation is not optional; it is the only rational response available to a country that cannot unilaterally halt the emissions of its neighbours or of the industrialised world.
The immediate priorities are neither complex nor prohibitively expensive. A national programme of lightning shelters, modelled on the cyclone shelter network that has demonstrably saved hundreds of thousands of lives over the past three decades, should be extended to every union parishad in the country’s most exposed districts. These structures do not need to be elaborate. They need to exist, be accessible, and be known. A complementary investment in last-mile early warning systems, using mobile alerts and community loudspeakers coordinated with the Bangladesh Meteorological Department’s upgraded forecasting capacity, could buy the minutes that mean the difference between safety and tragedy.
Over the longer term, Bangladesh must revisit its agricultural calendar and labour practices. If pre-monsoon storms are going to intensify, and the science says they will, then the hours during which rural workers are exposed in open fields should be governed by weather data, not only by planting schedules. The reforestation of rural areas, already overdue for reasons of flood management and biodiversity, would restore some of the natural protection that tall tree canopies once provided against direct strikes.
Finally, this country deserves a candid regional conversation about transboundary air pollution. If aerosol loading from industrial and agricultural sources across the border is measurably amplifying lightning mortality in Bangladesh, that is a legitimate subject for diplomatic engagement under the frameworks of the South Asian Association for Regional Cooperation. Environmental harm does not stop at borders, and neither should accountability.
If climate science is telling us that this number will grow, and it is, then the ethical obligation to act is not diminished by the fact that the victims are poor, rural, and individually invisible in the national data. It is, if anything, increased. The sky over Bangladesh is changing. The question is whether the institutions meant to protect their people will change fast enough to keep up. I believe they can. I am no longer confident they will, unless we start treating it as the crisis it already is.
Arghya Protik Chowdhury is a student of environmental science at Bangladesh University of Professionals.
