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Understanding the evolution of debris-covered glaciers in High Mountain Asia, the physical processes governing the effect of debris cover on mass balance, and the response of debris-covered glaciers to climatic change are key for assessing water resources, the contribution of glaciers to sea level rise and the potential for glacier related hazards such as glacier lake outburst floods (GLOFs) related to moraine-dammed lakes. Here we illustrate the effects of recent glacier recession on the development of landforms and sediments at Ponkar Glacier, a debris-covered glacier in the Manaslu area of the Nepal Himalaya using a combi-nation of 2019 RapidEye satellite image (5 m spatial resolution), drone imagery (50 cm) and field observations. We describe the key features of the glacier and its ice-surface morphology, including size and extent of flow units and tributary glaciers, supraglacial features of the debris cover and vegetation. Geomorphological mapping is used to describe the moraines, proglacial geomorphology, outwash plains and proglacial streams, the development of new ice-marginal ponds and changes in vegetation. Moraines generally have steep and rapidly degrading inner faces and mature vegetation, including trees, on their outer flanks. They are typically com-posed of diamicton and silty or sandy boulder gravel. Large outer moraines are separated from the surrounding val-ley sides by 'ablation valleys'. We conclude by putting the landforms and sediments developed at Ponkar Glacier into a discussion of the likely future evolution of high-eleva-tion debris-covered glaciers

The Randolph Glacier Inventory (RGI) is a globally complete collection of digital outlines of glaciers, excluding the ice sheets, developed to meet the needs of the Fifth Assessment of the Intergovernmental Panel on Climate Change for estimates of past and future mass balance. The RGI was created with limited resources in a short period. Priority was given to completeness of coverage, but a limited, uniform set of attributes is attached to each of the ~198 000 glaciers in its latest version, 3.2. Satellite imagery from 1999–2010 provided most of the outlines. Their total extent is estimated as 726 800 ± 34 000 km2. The uncertainty, about ±5%, is derived from careful single-glacier and basin-scale uncertainty estimates and comparisons with inventories that were not sources for the RGI. The main contributors to uncertainty are probably misinterpretation of seasonal snow cover and debris cover. These errors appear not to be normally distributed, and quantifying them reliably is an unsolved problem. Combined with digital elevation models, the RGI glacier outlines yield hypsometries that can be combined with atmospheric data or model outputs for analysis of the impacts of climatic change on glaciers. The RGI has already proved its value in the generation of significantly improved aggregate estimates of glacier mass changes and total volume, and thus actual and potential contributions to sea-level rise.