April heatwave in north India driven by climate change, finds study

Researchers point to absence of natural conditions for the four-degree Celsius temperature rise

The April 2025 heatwave in parts of northern India has been directly attributed to climate change, with researchers pointing to the absence of the natural conditions for the 4-degree Celsius increase in temperature.

In a study published in ClimaMeter, four researchers from universities in Singapore, the UK, and France investigated the surface temperature anomalies in India and Pakistan to understand their causal factors.

The heatwave, still ongoing in some parts of the country, that swept India and Pakistan pushed temperatures up to 49 degree Celsius in Pakistan’s Balochistan and above 40 degree C in New Delhi, up to 5 degrees Celsius above the seasonal average.

“The occurrence of large positive anomalies of temperature and extremely dry conditions in the pre-monsoon season is becoming commonplace in South Asia, as shown by the persistent and spatially extended events in 2015, 2019, 2022, and 2024, which have led to thousands of deaths and disruption to ecosystem and society, with temperature records being shattered every few years,” the researchers said.

Gianmarco Mengaldo of the National University of Singapore, Chen Chen of CCRS, Singapore, Valetio Lucarini of Leicester University, and Davide Faranada of IPSL-CNRS, France, came together with an approach that looked for weather situations similar to the current heatwave that were observed in the past.

“We analysed how events similar to the meteorological conditions leading to the April 2025 India and Pakistan heatwave have changed in the present (1987–2023) compared to what they would have looked like if they had occurred in the past (1950–1986) in the region,” Mengaldo told DH.

The changes showed that climate change has led to a condition where temperatures are 4 degree C warmer in the present.

“We find that sources of natural climate variability, notably the El Nino-Southern Oscillation, may have influenced the event. However, since the current phase is ENSO-neutral, the observed changes in the event, compared to the past, are likely due to human-driven climate change, with only a minor contribution from natural variability,” the researchers said.

The land use change only added to the problem of rising temperatures. “Changes in urban areas reveal that New Delhi, Jaipur, and Islamabad are experiencing warmer conditions,” the study noted.

The researchers concluded that meteorological conditions similar to the April 2025 India and Pakistan heatwave were 4 degree C warmer than in the past.

“We interpret the heatwave as an event driven by very exceptional meteorological conditions whose characteristics can mostly be ascribed to human-driven climate change,” the study said.