- Air pollution — especially from transboundary dust and sulfate particles — is intensifying lightning activity in Bangladesh, particularly during the pre-monsoon season. Studies show that these pollutants, mostly coming in from northern and western India, alter cloud dynamics and increase lightning frequency.
- Bangladesh records the highest lightning-related death density in South Asia, with over 4,000 deaths since 2010. Vulnerable rural populations with limited infrastructure and outdoor labor during harvest seasons are victims of these fatalities.
- Experts urge Bangladesh to strengthen early warning systems, improve air quality monitoring, and reduce both domestic and cross-border pollution through coordinated policies targeting traffic emissions, industrial sources and open burning.
Bangladesh, one of the world’s most climate-vulnerable countries, is witnessing a troubling rise in lightning-related deaths. Scientists point to a strong link between increased lightning activity and worsening air pollution, much of which is carried in from across its borders.
A new study, which analyzed six years of lightning and air quality data (2015-20), has found a strong correlation between lightning frequency and elevated concentrations of airborne dust and sulfate particles. These pollutants peak during the pre-monsoon months, particularly April and May — also the time when lightning strikes are most frequent.
“We identified two major pollutants — dust and sulfate — that help create the right conditions for more lightning during Bangladesh’s pre-monsoon season,” says Ashraf Dewan, co-author of the study and an associate professor at Australia’s Curtin University.
He explains that these pollutants act alongside atmospheric factors like Convective Available Potential Energy (CAPE), altering how clouds form and making it easier for electrical charges to build up inside storm clouds, ultimately leading to more lightning.
The lightnings strike over Bangladesh, but these pollutant particles are not all homegrown. The study links the uptick in lightnings to the transport of large volumes of dust and sulfate aerosols from agricultural burning and industrial emissions in northern and western India, carried into Bangladesh by upper-level westerlies. The study found that, during peak lightning season, dust levels were 88% higher and sulfate levels 51% higher than during the secondary peak in August-September.
However, Dewan stresses, this isn’t a simple “more pollution equals more lightning” equation. “There’s a threshold effect,” he says. “When Bangladesh’s already high local pollution combines with transboundary pollutants, lightning activity intensifies significantly.”
The research paints a complex picture: While pollutants such as dust, sulfates and ozone are associated with increased lightning activity, finer particles, like those with diameters of 2.5 microns or less (or PM2.5) and PM10, appear to suppress it.
A study by Saint Louis University in Missouri, U.S., supports the case for transboundary pollution. It found that fine particulate matter (PM2.5) across South Asia is heavily influenced by long-range transport of aerosols and biomass burning smoke, particularly from the Indo-Gangetic Plain. These pollutants travel thousands of kilometers, moving eastward along the Himalayas and southward over the Bay of Bengal,