A dataset of spatial distribution of degree-day factors for glaciers in High Mountain Asia

Abstract

The degree-day model, a widely used approach for ice- and snow-melt computation, rests upon a relationship between snow or ice melt and air temperature that is usually expressed in the form of positive temperature. The degree-day factor (DDF) is an important parameter for the model, and its spatial variation largely affects the accuracy of snow- and ice-melt simulations. Across High Mountain Asia (HMA), only a few glaciers have long-term observations over the past decades, leading to be unable to provide necessary parameters for regional melting simulation based on degree-day models. In this study, we collected investigations and observations on 40 glaciers located on different regions in HMA, and estimated the transfer functions for snow and ice DDFs. Then, we obtained the dataset of spatial distributions of DDFs for snow and ice in HMA. These data, with a spatial resolution of 0.5°, were stored in GeoTIFF format in 32-bit floating point. A comparison between regional mass balance simulations using this dataset and observations in a typical region confirms its accuracy. Therefore, the dataset can provide model parameters for the study of regional glacier melting process and its impact on water resources and associated glacier disasters in HMA, and can provide necessary data support for further analysis of glacier change and climate change, water resources change and its disaster effects in HMA.