Glacier elevation changes data in the High Mountain Asia derived from multi-temporal digital elevation models since the 1960s

Knowledge about the long-term response of High Mountain Asia (HMA) glaciers to climatic variations is paramount because of their important role in sustaining Asian river flow. Here. a satellite-based time series of glacier mass balance for seven climatically different regions across HMA since the 1960s were estimated by DEM differencing of multi-temporal optical data. The DEMs were corrected for planimetric and altimetric shifts using SRTM as a reference. Elevation dependent biases, present due to the tilt between two DEMs, were also estimated for each DEM using two-dimensional first order polynomial trend surfaces relative to the SRTM DEM. To remove outliers, we analyzed individual glacier elevation differences for each 100 m altitude bin. Considering the heterogeneity of the thickness change in glacierized terrain, outliers were removed by using an elevation dependent sigmoid function. Our study reveals a constant mass loss in all regions even in regions where glaciers were previously in balance with climate.