Krzysztof MIGAŁA1, Bogumiła A. PIWOWAR2 and Dariusz PUCZKO3

A meteorological study of the ablation process on Hans Glacier, SW Spitsbergen

 Polish Polar Research 27 (3), 2006: 243-258

ABSTRACT: The ablation of glaciers is an important factor in energy exchange between the atmosphere and land ice masses. The dynamics of ablation closely reflects climate changes and is important for the estimation of the outflow of meltwater, which, having penetrated a glacier to bedrock, stimulates its velocity by increasing basal sliding. More detailed studies using automatic weather stations (AWS) and the calculation of the energy budget are rarely conducted on small glaciers. The mass balance of the Hans Glacier has been monitored since 1989. Its intensified monitoring using AWS began in 2003. The results show that ablation depends more evidently on the daily mean and maximum air temperature and wind speed than on total and net radiation. Ablation, both that controlled by sonic height ranger and that measured manually on stakes, was compared with the values calculated on the basis of energy flux formulas applied by Oerlemans (2000). The statistical results allowed us to construct empirical equations, which in turn enabled us to compute the course and total ablation during the summer seasons. It can be described on the basis of two primary meteorological elements (air temperature and wind speed), as recorded in the station representing the regional area (Hornsund) or measured in situ on the glacier. Standard measurements of ablation from the years 1989-2004 were used to verify empirical model. The computed mean value of summer ablation for 1989-2004 was calculated at 1.35 m , differing from real measurements by only 10% (with SD = 0.18). The results obtained illustrate that an empirical equation can be applied in time series analyses. A regional ablation model enables us to investigate the mass-balance history of glaciers on the basis of meteorological data.

Key words: Arctic, Spitsbergen , Hans Glacier, energy budget of ablation.

Address: (1) Instytut Geografii i Rozwoju Regionalnego, Uniwersytet Wrocławski, Kosiby 6/8, 51-670 Wrocław, Poland, migalak@meteo.uni.wroc.pl , (2) Wydział Nauk o Ziemi, Uniwersytet ¦l±ski, Będzińska 60, 41-200 Sosnowiec, Poland, bpiwowar@wnoz.us.edu.pl, (3) Instytut Geofizyki, Polska Akademia Nauk, Księcia Janusza 64, 01-452 Warszawa, Poland, dp@igf.edu.pl