Some 57% of districts in India, which are collectively home to more than three quarters of the national population, now face a ‘high’ to ‘very high’ risk from extreme heat, a new study by the Council on Energy, Environment and Water (CEEW) has found.
The study, How Extreme Heat is Impacting India: Assessing District-level Heat Risk, which was funded by Rohini Nilekani Philanthropies (RNP) and HSBC India, assessed 734 districts using 35 climate and socioeconomic indicators, to present a picture of the level of heat risk affecting neighbourhoods across the country.
Some 417 districts fell in the ‘high’ and ‘very high’ risk categories while 201 were classified as ‘moderate’ risk, and 116 districts were classed as relatively less exposed.
Warm nights and increased humidity
According to the findings, very warm nights – when temperatures remain unusually high even after sunset – are increasing more rapidly than very hot days, with close to 70% of districts experiencing five or more such nights each summer. In Mumbai for example, 15 more very warm nights were recorded compared to the average for the previous three decades.
Other concerning factors included increasing relative humidity across North India, particularly in the Indo-Gangetic Plain, and an increase in heat exposure in dense, urban, and economically-critical districts such as Delhi, Mumbai, Ahmedabad, Hyderabad, Bhopal, and Bhubaneswar.
‘A present reality’
“Heat stress is no longer a future threat—it’s a present reality,” commented Dr Arunabha Ghosh, CEO, CEEW. “Increasingly erratic weather due to climate change – record heat in some regions, unexpected rain in others – is disrupting how we understand summer in India. But the science from the study is unequivocal: we are entering an era of intense, prolonged heat, rising humidity, and dangerously warm nights.
“We must urgently overhaul city-level Heat Action Plans to address local vulnerabilities, balance emergency response measures with long-term resilience, and secure financing for sustainable cooling solutions. Further, it’s time to move beyond daytime temperature thresholds and act on what the data tells us: the danger doesn’t end when the sun sets.”
In terms of humidity, historically drier cities like Delhi, Jaipur, Kanpur, and Varanasi are now experiencing humidity levels that are 10% higher than a decade ago, while urban ‘heat islands’ are affecting metropolitan hubs such as Delhi, Mumbai, Ahmedabad, and Chennai.
Dr Vishwas Chitale, senior programme lead, CEEW, added that while India has made positive strides in responding to extreme heat, the time has come to invest in long-term resilience.
“Solutions like parametric heat insurance, early warning systems, net-zero cooling shelters, and cool roofs must become core to heat action plans,” Chitale commented. “States like Maharashtra, Odisha, Gujarat and Tamil Nadu are already taking pioneering steps by integrating climate and health data into local planning. Now is the time to scale these efforts nationally, using district-level risk assessments to prioritise funding and action.” Read more here.
