Study finds average temperature across India rose by 0.89 degrees Celsius, extremes becoming common

India’s average temperature increased by 0.89 degrees Celsius during 2015-2024, compared to the first quarter of the twentieth century, with temperature extremes becoming more frequent across parts of the country, according to a study.

An additional warming of 1.2 to 1.3 degrees Celsius is projected by mid-century under a moderate emissions scenario, compared to 1995-2014.

Researchers from Indian Institute of Tropical Meteorology in Pune and Krea University in Sri City, Andhra Pradesh, among other institutes, provided an update on observed and projected trends of climate change in the country.

Datasets, including those from the India Meteorological Department, and global climate models were analysed.

Duration of marine heatwaves — high ocean surface temperatures which can damage coastal ecosystems — could increase from about 20 days per year during 1970-2000 to nearly 200 days per year by mid-century, findings published in the PLOS Climate journal indicate.

The team added that compound events — where climate hazards arise not in isolation but through an interaction — such as ‘heatwave-drought’ are of central concern for India.

“India’s average temperature has risen by approximately 0.89 degrees Celsius during 2015-2024 relative to 1901-1930. Models project additional warming of about 1.2-1.3 degrees Celsius over India by mid-century under SSP2-4.5 (relative to the recent past (1995-2014),” the authors wrote.

They added that while India’s warming appears muted compared to the global land temperature warming of about 1.42 degrees Celsius over the same period, several previous studies have reported temperature extremes becoming more frequent across many parts of India.

‘SSP2-4.5’ refers to a future scenario in a warmer world with ‘moderate greenhouse gas emissions’ — also called ‘middle of the road’ scenario — for which studies have predicted a global warming of around 0.24 degrees Celsius per decade during 2015-2050.

The authors also found that average southwest monsoon rainfall has declined by 0.5 to 1.5 millimetres per day every decade over the Indo-Gangetic Plains and northeast India over the past 70 years.

However, extreme precipitation events have become more intense, with coastal Gujarat experiencing about 0.15 additional extreme events every decade during 1951-2024, they said.

Further, the Hindu Kush Himalaya — the western part of the Hindu Kush Himalayan Region — have witnessed an accelerated warming of about 0.28 degrees Celsius per decade during 1950-2020, the team said.

Losses in glacier mass were found to have accelerated from 0.17 metre-water equivalent per year during 2000-2009 to 0.28 metre-water equivalent per year during 2010-2019.

Prevalence and intensity of compound climate hazards, which cause a more severe impact than any of the individual events would cause, are projected to increase with warming, but studies are sparse in the Indian context, making it “critically important” that research in this regard is accelerated, the authors noted.