Intensified paraglacial slope failures due to accelerating downwasting of a temperate glacier in Mt. Gongga, southeastern Tibetan Plateau

Abstract. Topographic development via paraglacial slope failure (PSF) represents a complex interplay between geological structure, climate, and glacial denudation. Southeastern Tibet has experienced amongst the highest rates of ice mass loss in High Mountain Asia recent decades, but few studies have focused on implications this stability slopes. We used repeat satellite- unpiloted aerial vehicle (UAV)-derived imagery 1990 2020 as basis for mapping PSFs from slopes adjacent to Hailuogou Glacier (HLG), 5 km long monsoon temperate valley glacier Mt. Gongga region. observed lowering tongue surface at up 0.88 m a−1 period 2000 2016, whilst overall bare ground area (PBGA) glacier-adjacent increased 0.31 ± 0.27 km2 1.38 0.06 2020. Decadal PBGA expansion were ∼ 0.01 a−1, 0.02 0.08 periods 1990–2000, 2000–2011, 2011–2020 respectively, indicating an increasing rate PBGA. Three types PSFs, including rockfalls, sediment-mantled slides, headward gully erosion, mapped, with total 0.75 0.03 South-facing (true left glacier) exhibited more destabilization (56 % PSF area) than north-facing right) (44 area). Deformation moraine (mean 1.65–2.63 0.04 cm d−1) increase erosion activity ice-marginal tributary valleys caused by drop local base level (gully are 0.76–3.39 occurred tandem downwasting. also observe deformation ice, possibly driven lateral moraine, been reported other deglaciating mountain catchments. The formation, evolution, future trajectory HLG (as well monsoon-dominated areas) related history, rapid downwasting leading exposure steep, unstable bedrock slopes, climatic conditions that promote instability, such very high seasonal precipitation temperature fluctuations conducive freeze–thaw segregation processes.