Mountains around the world are heating up more quickly than surrounding lowlands, according to a comprehensive study, leading to shifts in snow, rain, and water supplies that affect over a billion people. The research highlights elevation-dependent climate change, with temperatures rising 0.21°C per century faster in mountain regions. These changes pose risks to ecosystems, water resources, and human safety in areas like the Himalayas.
A major global review published in Nature Reviews Earth & Environment has revealed that mountain regions are experiencing accelerated warming compared to nearby lowland areas. Led by Associate Professor Dr. Nick Pepin of the University of Portsmouth, the study analyzes data from 1980 to 2020 across key mountain systems, including the Rocky Mountains, the Alps, the Andes, and the Tibetan Plateau.
The research identifies "elevation-dependent climate change" (EDCC) as a key process, where environmental shifts intensify with altitude. Key findings include mountain temperatures warming at an average rate of 0.21°C per century faster than lowlands, alongside erratic rainfall patterns and a transition from snowfall to rain. "Mountains share many characteristics with Arctic regions and are experiencing similarly rapid changes," Dr. Pepin stated. "This is because both environments are losing snow and ice rapidly and are seeing profound changes in ecosystems."
These transformations have far-reaching implications. More than one billion people rely on mountain snow and glaciers for freshwater, particularly in densely populated nations like China and India, which depend on the Himalayas. Dr. Pepin warned, "The Himalayan ice is decreasing more rapidly than we thought. When you transition from snowfall to rain because it has become warmer, you're more likely to get devastating floods. Hazardous events also become more extreme."
Ecological impacts are also severe, with plants and animals migrating upslope in search of cooler conditions, potentially leading to species loss as they reach mountain summits. Recent events, such as the deadly floods in Pakistan this summer that killed over 1,000 people due to intense monsoon storms and mountain cloudbursts, illustrate the growing dangers.
The review builds on a 2015 study by the same team in Nature Climate Change, which first evidenced elevation-based warming. However, challenges persist, including data gaps from remote, harsh mountain environments. "Mountains are harsh environments, remote, and hard to get to," noted Dr. Nadine Salzmann from the WSL Institute for Snow and Avalanche Research SLF in Davos, Switzerland. "Therefore, maintaining weather and climate stations in these environments remains challenging."
Scientists call for enhanced monitoring and finer-scale climate models to better predict changes. Dr. Emily Potter of the University of Sheffield added, "The good news is that computer models are improving. But better technology alone isn't enough—we need urgent action on climate commitments and significantly improved monitoring infrastructure in these vulnerable mountain regions."