India’s Cities Could Heat Up Twice as Much as Climate Models Predict Amid Rising Heat Stress

Climate models may be underestimating—by anything from half to two degrees—how much hotter India’s non-metropolitan cities can get from global warming relative to rural areas, according to a report published by the journal, Proceedings of the National Academy of Sciences (PNAS).

The report assessed how temperatures would increase in the 104 “medium-sized” cities in the tropical and sub-tropical regions under a 2 degrees Celsius warming scenario, the emissions path that the globe is currently on.

According to the report, Patiala, Punjab, is an extreme "outlier" where land surface temperatures could rise at twice the rate of warming predicted by global climate models compared to the surrounding rural region. The only other location in the researchers' analysis that displayed as much differential warming was Kasur in Pakistan.

This implies that when urban heat-island effects are taken into consideration, the rise in Patiala would actually be 4 degrees Celsius, even though the models used in the assessments by the Intergovernmental Panel on Climate Change predict a 2 degree Celsius increase. The availability of water, public spending on cooling, and vulnerability to heat strokes can all be significantly impacted by an additional 2 degrees Celsius of temperature increase.

Urban Heat Island Effect Makes Cities Hotter

For all the studied cities in India, the cities experience about an additional 45% warming than what the Earth System Models (ESMs) project for the broader region. This raises expected city warming from nearly 2.2 degrees Celsius, as suggested by climate models alone, to roughly 2.6-2.7 degrees Celsius once urban specific effects are included. The urban heat island effect makes the cities hotter than nearby rural land.

According to the Intergovernmental Panel on Climate Change (IPCC) and the World Health Organisation, urban areas can be several degrees warmer than surrounding rural regions, especially at night, compounding heat stress risks. In addition, studies by NASA and World Bank show that rapidly urbanising cities in the Global South are particularly vulnerable, as limited green cover, rapid urbanisation and high population density reduce natural cooling. Without urban planning, future warming impacts in cities may be significantly underestimated.

The September 2025 World Bank report also stated that the costs of inaction are severe, with heatwaves expected to become frequent and intense and elderly, outdoor workers and low-income families being among the vulnerable groups.