World Environment Day Special : Democratise Thermal Comfort

45 In cities vulnerable to heat, thermal comfort is crucial to one's health, well-being and productivity. Building wisely can not only ensure it for all, but also decarbonise the built environment to help mitigate global warming. An analysis by Mitashi Singh, Sugeet Grover, Rajneesh Sareen And Anumita Roychowdhury

- Mitashi Singh, Sugeet Grover, Rajneesh Sareen And Anumita Roychowdhury

This summer, the impact of climate change has become more evident for India, and so does the scale of the challenges ahead. Millions suffered under extreme heatwaves that started unusually early in March, pushing the average temperature of the month to 33.1°C, the warmest in 122 years. Till the first week of June, 17 states and Union territories have recorded heatwaves, with several of them experiencing hotter- and longer-than-the usual hot spell The Himalayan state of Himachal Pradesh experienced its first intense heatwave since 1970, as per EnviStats 2022, an annual report by the Union Ministry of Statistics and Programme Implementation. Data with the India Meteorological Department (IMD) shows that the state has since March experienced third highest days of heatwaves, after Rajasthan and Madhya Pradesh.

Such events, once considered freakish, are going to become commonplace as heatwaves become more frequent and can be 25 times longer in the coming decades, between 2036 and 2065, warns the G20 Climate Risk Atlas for India, released in 2021. While extreme heat beyond 35°C can lead to serious health problems, its effects get compounded when relative humidity also increases. In a hot weather, our body works to maintain tolerable temperature by sweating. But if it is humid, the sweat cannot evaporate as quickly, crippling the body's cooling method. This adds to thermal stress and can cause medical emergencies.