Elevation-dependent landsliding driven by climate change in the eastern Himalayan syntaxis

Abstract Has climate change escalated landsliding in high mountain regions? We compiled an inventory of 8607 climate-related landslides (1987–2020) in the eastern Himalayan syntaxis to investigate how hillslopes in high mountains, particularly cryospheric landscapes, are responding to recent trends in precipitation and temperature. We identify a five-fold increase in annual landslide volumes at high elevations (>3000 meters above sea level) over the past three decades. The landslide distribution is observed migrating upslope in the wake of retreating glaciers and melting permafrost—a trend underpinned by a warming-induced shift in precipitation falling as rain rather than snow. Today, climate-related landsliding in the eastern Himalayas is driving an extreme denudation rate of 1.0 ± 0.3 mm yr–1, comparable to that of alpine glaciation. Our findings imply that landslide activity across High Mountain Asia is evolving rapidly under climate change, amplifying the sediment cascade and heightening the risk of cascading mountain hazards.