Zubaida starts her day at eight in the morning, sorting discarded plastics, glass, and chemicals with her bare hands, to collect items she can sell. With waste-segregation centers in this part of East Delhi currently shut down, she and other waste-pickers from the Seemapuri slum work outside by a dusty road through the hottest hours of the day, under the blazing sun. There is no fan or shade. With Delhi’s heat wave season here, they are constantly exposed to intense high temperatures.
On June 11, the India Meteorological Department (IMD) issued a red alert for Delhi, warning of a high risk of heat illness and heat stroke. Temperatures that week pushed beyond 45 degrees Celsius (113 degrees Fahrenheit) across northern India, with the real-feel temperature, which factors in how humidity augments the effects of heat, spiking at an alarming 54 degrees Celsius. Prolonged exposure to such high heat can raise a person’s body temperature to dangerous levels. It’s potentially fatal.
In the face of this inferno, the IMD advised people to avoid going outdoors during the daytime, and markets and streets were deserted during the day. But even when extreme heat strikes, Delhi’s large, informal workforce continues to work. Street vendors, rickshaw pullers, and waste pickers have reported dizziness, infections, breathing difficulties, and persistent fatigue during recent heat waves. “We cannot stop,” says Zubaida. “We earn each day to eat each day. If we miss a day, we miss a meal.”
At present, heat action plans (HAP) are India’s primary approach for managing heat waves and keeping essential services running. Developed annually by state, district, and city governments—the Delhi government released its citywide HAP for 2025 in April—these plans are designed to help cities prepare for, respond to, and recover from extreme heat. And they’re not working.
This has driven nonprofits and research organizations to show how HAPs can be improved—with one key idea being to use geographic information systems (GIS) that combine satellite imagery with local data to provide cities with a granular, building-by-building views of their heat. Action plans, often plagued by generalization, can then be tailored to better protect those at the highest risk.
Places like Ahmedabad and Tamil Nadu have seen falls in heat-related illnesses and deaths since introducing their plans (Ahmedabad’s was the first to be implemented in India, back in 2013). But with most HAPs there are still major gaps when it comes to their implementation, coordination, and funding. A 2023 study found that 95 percent of HAPs do not have detailed mapping of heat-prone areas or vulnerable populations. Without this kind of granular data, it becomes difficult to allocate resources where they are needed most.
What is still missing is a hyperlocal targeted response to risk, says Radhika Khosla, associate professor at the Smith School of Enterprise and the Environment at the University of Oxford. She explains that heat risk is really the intersection of three things: the hazard—where temperature and humidity are highest within different city regions; exposure—which communities are most exposed to heat; and their vulnerability—factors like socioeconomic status, health conditions, levels of outdoor work, access to electricity, and the conditions of the built environment. Right now, most plans aren’t collecting and analyzing this sort of data, Khosla says. “Often where the actions are taken may not be where the most vulnerable are.”