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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

Debris surface temperature is a function of debris characteristics and energy fluxes at the debris surface. However, spatial and temporal variability in debris surface temperature, and the debris properties that control it, are poorly constrained. Here, near-surface debris temperature (T-s) is reported for 16 sites across the lower elevations of Khumbu Glacier, Nepal Himalaya, for the 2014 monsoon season. The debris layer at all sites was 1m thick. We confirm the occurrence of temporal and spatial variability in T-s over a 67-day period and investigate its controls. T-s was found to exhibit marked temporal fluctuations on diurnal, short-term (1-8days) and seasonal timescales. Over the study period, two distinct diurnal patterns in T-s were identified that varied in timing, daily amplitude and maximum temperature; days in the latter half of the study period (after Day of Year 176) exhibited a lower diurnal amplitude (mean = 23 degrees C) and reduced maximum temperatures. Days with lower amplitude and minimum T-s were concurrent with periods of increased seasonal variability in on-glacier air temperature and incoming shortwave radiation, with the increased frequency of these periods attributed to increasing cloud cover as the monsoon progressed. Spatial variability in T-s was manifested in variability of diurnal amplitude and maximum T-s of 7 degrees C to 47 degrees C between sites. Local slope, debris clast size and lithology were identified as the most important drivers of spatial variability in T-s, with inclusion of these three variables in the stepwise general linear models resulting in R-2 0.89 for six out of the seven sites. The complexity of surface energy fluxes and their influence on T-s highlight that assuming a simplified relationship between air temperature and debris surface temperature in glacier melt models, and a direct relationship between debris surface temperature and debris thickness for calculating supraglacial debris thickness, should be undertaken with caution.