How South Asia Can Adapt to Extreme Heat

Last year was the hottest the earth has ever experienced. There has been little sign of high temperatures abating; 2025 began with the hottest January on record. Climate change has doubled the number of days of extreme heat in 195 countries and territories, according to new research by Climate Central and the Red Cross Red Crescent Climate Centre. In April 2024, Munshiganj in Southwest Bangladesh experienced a 100-year heatwave. Even under the most optimistic projections, such events will be exceeded in the future, on average, once every 6 years. Despite the clear need for urgent action to combat the growing threat posed by rising temperatures, we remain inert. Investment, research and implementation to address the dangers of extreme heat must ramp up if we are to avoid loss of life. Southwest Asia, South Asia, and Eastern China are among the regions most prone to extreme heat.  Extreme heat is measured via “wet-bulb temperatures,” a combined measure of temperature and humidity. In these regions, the wet-bulb temperature may reach 35 degrees Celsius, or 95 degrees Fahrenheit, if global climate change is not sufficiently mitigated. At this temperature, even the fittest human body can no longer cool itself through sweating, if such conditions extend for hours.  Projections indicate that by 2100, 70% of Indian, Pakistani, and Bangladeshi populations could be exposed to these extreme wet-bulb temperatures. This will pose severe health risks, especially for the elderly, outdoor laborers, and those in agriculture.  The implications are staggering. Areas around the Ganges and Indus river basins are on the frontline of an emergency, with extreme risks to humans increasing in these densely populated areas with limited access to cooling technologies. For tens of millions, escaping the heat is not as simple as turning on a fan or air conditioning. Rolling blackouts, water scarcity, and economic barriers strip away these options.  Current projections suggest that South Asia will experience heatwaves that go well beyond what humans are able to tolerate, pushing public health systems to the brink and triggering waves of climate migration. Recent projections suggest that heatwaves will become more frequent and severe in western Bangladesh under the business-as-usual scenario, exceeding the extreme danger threshold defined by U.S. National Weather Service criterion, which has rarely been observed in the current climate. Low-income urban areas are most at risk. With dense housing made of heat-retaining materials, little access to cooling technology, and limited tree cover and green space, these neighborhoods are already several degrees hotter than wealthier areas, resulting in urban heat inequality.  One solution is to inform frontline communities with the latest climate projections from sophisticated models describing evolving climate phenomena such as deadly heatwaves and destructive cyclones.  Projections from Jameel-Observatory Climate Resilience Early Warning System (JO-CREWSnet)—a collaboration between Community Jameel and MIT—are used to analyze human systems, identify high-risk hotspots, and develop and test effective solutions that are shared with villages in Southwestern Bangladesh and at the national level. In southwestern Bangladesh, JO-CREWSnet is experimenting with innovative solutions such as the Adaptation Fortress concept. A new design of shelters, equipped with modern cooling technology and powered by solar energy, would protect the local population not only from cyclones but also from heatwaves. Science speaks clearly, and the stakes are high. Policymakers must address extreme heat with the urgency it demands, implementing adaptive measures such as green infrastructure, urban and rural cooling projects, and higher building standards.  But adaptation alone is insufficient. Without aggressive action to curb carbon emissions, we are hurtling toward a future where entire sections of the globe may face extremely dangerous conditions.