Mountain regions are warming nearly 50% faster than the global average since 1950.
A new study published in Nature Reviews Earth and Environment found that high-altitude areas, including the Himalayas, are heating far more rapidly than lowlands, posing risks to over a billion people who rely on mountain ecosystems for water and stability.
Between 1980 and 2020, mountains experienced 0.21°C extra warming per century, 11.5 mm additional drying, and 25.6 mm faster snow melt compared to lowlands.
The research team, led by the University of Portsmouth, examined “elevation-dependent climate change,” driven by factors such as surface albedo, specific humidity, and aerosols.
Lead researcher Nick Pepin said mountains share characteristics with the rapidly warming Arctic, mainly due to the rapid loss of snow and ice.
He noted that climate change intensifies at higher elevations, though the most dramatic impacts often occur at intermediate elevations where snowlines are rising. Aerosols from populous regions like India and China can accelerate snow and ice melt when deposited at high altitudes.
Using global datasets and case studies from the Alps, Tibetan Plateau, and High-Mountains Asia, the team confirmed that mountain trends diverged from lowlands in temperature (+0.21°C), precipitation (–11.5 mm), and snow loss (–25.6 mm) per century. Climate models project continued mountain warming of 0.13°C per century through the 21st century, though precipitation forecasts remain uncertain.
The findings have major implications for countries like India and China, where shrinking Himalayan ice and a shift from snowfall to rainfall increase the risk of severe floods. Rapid warming is also reshaping ecosystems as trees and animals move upslope, eventually running out of habitat.
The study warned that these ongoing changes may be far-reaching and irreversible.