Strong El Niño could cause over 600 additional heat deaths in Bangladesh
More than 300 additional heat-related deaths could occur in Khulna alone between September 2026 and February 2027, according to a Climate Impact Lab estimate
More than 600 people in Bangladesh could die from additional heat between September 2026 and February 2027 as a powerful El Niño drives temperatures higher, according to an estimate by climate scientists.
The impact could be particularly severe in southern and southeastern Bangladesh, with Khulna, Barishal and Chattogram among the areas facing the highest heat-related mortality. Khulna alone could see about 310 additional heat-related deaths during the six-month period, according to the Climate Impact Lab.
The assessment comes as El Niño strengthens rapidly in the tropical Pacific. The World Meteorological Organization (WMO) says there is an exceptionally high likelihood—nearly 100%—that El Niño will persist through February 2027.
Keep updated, follow The Business Standard's Google news channel
The event is expected to reach very strong intensity before peaking towards the end of 2026. It could bring major shifts in temperature and rainfall patterns and increase risks from extreme heat, drought and flooding.
For Bangladesh, the warning comes amid growing exposure to extreme heat and other climate-related hazards. El Niño does not produce the same effects everywhere, however. Local impacts depend on location, season and other climate conditions.
The WMO's September–November 2026 outlook points to an increased likelihood of above-normal temperatures across much of the world's land areas.
Khulna among the hardest-hit areas
The Climate Impact Lab estimates heat-related mortality at the regional level, allowing researchers to identify areas where the human impact of extreme heat could be greatest.
In Bangladesh, Khulna, Barishal and Chattogram emerge among the areas facing significant additional heat mortality. Khulna accounts for about 310 of the roughly 600 additional deaths estimated for Bangladesh during the six-month period.
The figures refer to deaths above what would normally be expected during the same period in an average year.
They are modelled excess deaths, not observed fatalities. The estimate measures additional mortality associated with temperatures expected during the El Niño period.
The researchers used month-by-month relationships between temperature and mortality across 24,378 regions worldwide, combined with forecasts for temperatures in the months ahead.
They used 1996–2025 as the baseline, comparing expected mortality during the El Niño period with what would normally occur during the same months.
The assessment is intended to help identify areas where heat-response measures could have the greatest impact.
Bangladesh faces wider heat risks
Heat does not affect everyone equally. Outdoor workers, older people, those with limited access to cooling and people with limited access to healthcare can face greater risks during extreme temperatures.
Measures such as better heat forecasts, cooling facilities, additional medical capacity and protection for outdoor workers can help reduce exposure.
The risks also extend beyond heat.
A strong El Niño can alter rainfall patterns, increasing the risk of drought in some areas while bringing heavier rainfall and flooding elsewhere. Such changes can affect agriculture, water supplies and food security.
For Bangladesh, these pressures could add to the risks faced by communities already exposed to extreme heat and other climate-related hazards.
More than 450,000 deaths worldwide
Bangladesh's estimated toll is part of a much larger global picture.
More than 450,000 additional heat-related deaths are estimated worldwide during the current El Niño period, according to the researchers.
The countries facing the largest estimated impacts include Nigeria, Indonesia, Sudan, India and Brazil.
Across the Sahel, the estimate is 66,800 additional heat deaths between September and February.
Nigeria accounts for 31,400, followed by Sudan with 17,500, Niger with 10,000 and Chad with 8,000.
In Southeast Asia, the estimated additional deaths total 19,400 across the Philippines, Vietnam, Thailand and Cambodia.
Indonesia alone could see 19,300 additional heat deaths, while India could see 15,800 and Brazil 13,300.
The United States could see about 3,500 additional heat deaths during the period.
The differences reflect variations in temperature, population exposure and vulnerability, as well as access to measures that can protect people from extreme heat.
El Niño on a warmer planet
The additional heat cannot be attributed to El Niño alone.
El Niño is a natural climate phenomenon, but the current event is unfolding on a much warmer planet because of human-driven climate change.
The researchers estimate that global land temperatures during the event could be about 1.2°C above normal, with 44% more extremely hot days than would normally be expected.
They describe the event as a "postcard from the future", saying temperatures of this intensity could become increasingly common as the planet continues to warm.
The WMO cautions that the strength of El Niño alone does not determine weather conditions in individual countries. Other climate drivers, including conditions in the Indian and Atlantic oceans, can influence local temperatures and rainfall.
For September–November 2026, the WMO forecasts an increased likelihood of above-normal temperatures across almost all land areas.
Heat is only part of the threat
The current assessment covers September 2026 to February 2027, based on the available seasonal temperature forecasts.
But the researchers say elevated heat-related mortality could continue into June or July 2027 in some parts of the Northern Hemisphere.
For Bangladesh, the figures put a human cost on the additional heat expected during the coming months. With Khulna alone accounting for about 310 additional heat-related deaths, the southern and southeastern parts of the country could face a particularly heavy health burden as El Niño unfolds over an already warmer climate.
