520 million people in South Asia could face dangerous heat for at least one month a year by 2070, says World Bank report

By 2070, around 520 million people in the South Asian region will face a month or more of dangerous heat each year, four times as many as today. That exposure will be concentrated in cities, while the fastest warming is projected for the Himalayas and their foothills, according to a new World Bank report.

The report, A Livable Future: Protecting Jobs and Growth from Extreme Heat in South Asia’s Cities,” examines the growing risks of extreme heat in Bangladesh, Bhutan, India, the Maldives, Nepal and Sri Lanka.

The scale of exposure could increase dramatically in the coming decades. By 2070, about 1.1 billion people could experience at least one day of theoretically unlivable heat, compared with far fewer today. The number facing at least one month of such conditions annually could rise from about 120 million to 520 million, while nearly 63 million people could face three or more months of extreme heat each year. Such prolonged exposure could make outdoor work increasingly dangerous and constrain the daily lives of people without reliable access to cooling.

The report assesses current and projected impacts on health, productivity, and urban economies.

The cost of inaction

According to the report, dense urban areas in South Asia can remain more than 10 degrees Celsius hotter at night than the surrounding countryside.

Extreme heat is already taking a significant toll on health. Heat-related deaths are frequently recorded as cardiac or renal failure rather than being directly attributed to high temperatures, meaning the true burden is likely underestimated. In Bangladesh, India, Nepal and Sri Lanka, the estimated number of deaths in which high temperatures were a contributing risk factor increased from about 118,000 in 2000 to 230,000 in 2023, a rise of roughly 95 per cent. This increase is consistent with rising temperatures, population growth, population aging, and increasing exposure to heat.

The economic consequences are equally serious. According to the report, extreme heat is costing South Asia the equivalent of 31 million full-time jobs every year and could shrink the region’s economy by nearly 7 per cent by 2050, if countries do not take adaptation measures. This comes as the region is expected to add around 280 million working-age people by 2050.

The poorest and most vulnerable workers are likely to suffer the most. Informal workers can see their earnings fall by about 40 per cent during heatwaves, while rising costs for water, cooling and healthcare place additional pressure on households.

The report calls for extreme heat to be treated not merely as a seasonal disaster but as a central development challenge. It urges governments to integrate heat-risk management into urban planning, infrastructure development, public policy and private investment.

The assessment provides policymakers with a practical roadmap that can be implemented through existing institutions and financing mechanisms. It recommends investing in heat resilient infrastructure, strengthening Heat Action Plans, protecting vulnerable workers, expanding sustainable cooling, improving early warning systems, and mobilising public and private investment to build more resilient cities.

Many of the solutions already exist. Cities across South Asia are showing how Heat Action Plans, resilient infrastructure, urban greening, early warning systems, and efficient cooling can save lives, protect workers, and reduce economic losses. But, scaling these approaches will require stronger institutions, better coordination, and greater public and private investment.

The analysis was prepared with support from the Resilient Asia Programme, funded under the UK government’s Climate Action for a Resilient Asia programme of the Foreign, Commonwealth & Development Office.