An enhanced temperature-index glacier melt model including the shortwave radiation balance: development and testing for Haut Glacier d’Arolla, Switzerland

Abstract

An enhanced temperature-index glacier melt model, incorporating incoming shortwave radiation and albedo, is presented. The model is an attempt to combine the high temporal resolution and accuracy of physically based melt models with the lower data requirements and computational simplicity of empirical melt models, represented by the ‘degree-day’ method and its variants. The model is run with both measured and modelled radiation data, to test its applicability to glaciers with differing data availability. Five automatic weather stations were established on Haut Glacier d’Arolla, Switzerland, between May and September 2001. Reference surface melt rates were calculated using a physically based energy-balance melt model. The performance of the enhanced temperature-index model was tested at each of the four validation stations by comparing predicted hourly melt rates with reference melt rates. Predictions made with three other temperature-index models were evaluated in the same way for comparison. The enhanced temperature-index model offers significant improvements over the other temperature-index models, and accounts for 90–95% of the variation in the reference melt rate. The improvement is lower, but still significant, when the model is forced by modelled shortwave radiation data, thus offering a better alternative to existing models that require only temperature data input.

Impact of supraglacial deposits of tephra from Grímsvötn volcano, Iceland, on glacier ablation

“…Thereby, the latter is expressed as a function of calculated albedo (α) and measured global radiation (R). This general type of ablation model was presented by Pellicciotti and others (2005) and has been successfully applied in other studies (e.g. Möller and others, 2013).…”

Future high-mountain hydrology: a new parameterization of glacier retreat

“…The climatic forcing acting on the glacier can be described using mass balance models of varying complexity that relate meteorological variables to accumulation and ablation rates at the glacier surface (e.g., Arnold et al, 1996;Hock, 1999;Klok and Oerlemans, 2002;Pellicciotti et al, 2005). The ice dynamics of alpine glaciers have been assessed in many glaciological studies ranging from simple flowline models (e.g., Greuell, 1992;Oerlemans, 1997;Sugiyama et al, 2007) to complex 3-D ice flow models (Hubbard et al, 1998;Gudmundsson, 1999;Jouvet et al, 2008).…”

The influence of resolution and topographic uncertainty on melt modelling using hypsometric sub‐grid parameterization

“…However, if reference melt or temperature data is inaccurate or of insufficient spatial density, TIMs can significantly over-or underestimate melt and fail to reproduce observed spatial variation. To overcome these limitations, TIMs have been extended by a variety of authors to incorporate a radiation component (Pellicciotti et al, 2005;Schneeberger et al, 2003;Hock, 1999;Williams and Tarboton, 1999;Cazorzi and Fontana, 1996). Via calculation of solar radiation, these extended models explicitly incorporate topographic parameters such as slope and aspect, horizonand self-shading, as well as time of year and latitude.…”