A new study combining 120 years of observed temperature records (1901–2020) has found that the western Himalaya, comprising Ladakh, Jammu and Kashmir and Himachal Pradesh, is warming faster than the central and eastern stretches of the range in every season.
The study found that winters are warming faster than spring, while night-time temperatures are rising faster than daytime highs. It also projected that springtime snow loss over the western Himalaya could be three times higher by the end of the century under a high-emission pathway than under a low-emission scenario.
The study, titled Vulnerability of the Himalayan Region Under Climate Change, was published in the Journal of Earth System Science. Led by the Department of Remote Sensing and Geoinformatics at Birla Institute of Technology (BIT), Mesra, Ranchi, the research was conducted in collaboration with the Indian Institute of Tropical Meteorology (IITM), Pune, and Ashoka University.
It assessed changes in temperature and snow cover across three sectors of the Indian Himalayan range and projected how these changes could evolve by 2100.
“The Himalaya is often discussed as a single system, but our observations and models both say otherwise. The western Himalaya consistently emerges as the most sensitive stretch — it warms the most and loses the most snow under every pathway we tested. That has direct consequences for the states that sit in it,” said Protyusha Mukhopadhyay, lead author and researcher at BIT, Mesra.
As per the findings, if emissions remain high, winters during 2081-2100 could be 7.18°C warmer in the western Himalaya, 6.71°C warmer in the central Himalaya and 5.82°C warmer in the eastern Himalaya compared with the early 1900s.
“In the west and centre, winters are warming faster than springs. Less snow on the ground would mean a darker surface, which absorbs more heat, which melts more snow. It matters because winter is the season in which snow is supposed to build up; warmer winters mean less snow banked for the melt months that follow,” said Parthasarathi Mukhopadhyay, corresponding author and researcher at Ashoka University.
One of the clearest signals in the observational record is that night-time temperatures are rising faster than daytime temperatures across the western and central Himalaya.
“Rising night-time temperatures are the quieter half of this story, and arguably the more consequential one. When the cold nights that let snowpack recover start disappearing, you change the melt cycle itself — not how much snow falls, but when the water arrives downstream,” said Dr Swagata Payra, co-author and researcher at BIT, Mesra.
Across all three sectors, the study found greater snow loss in spring than in winter, with the western Himalaya recording by far the largest decline. The researchers measured snow loss in terms of the amount of snow, by weight, sitting on each square metre of ground.
