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A meteorological station was operated in the ablation area close to the equilibrium line on Storglaciären, northern Sweden, during the ablation seasons of 1998 to 2000. The station recorded longwave and shortwave radiation, air temperature, humidity, precipitation, wind speed and wind direction. The data were used to calculate the energy balance, applying the bulk-aerodynamic approach for turbulent fluxes, and to calculate melt rates under the investigation periods. The calculated cumulative melt was compared to melt measured by a SR50 Sonic Ranging Sensor. Results show that calculated melt overestimates measured melt in 1998. Comparison for calculated and measured cumulative melt in 2000 show good agreement, while the estimation of cumulative melt in 1999 is problematic due to repeated snowfall under the ablation season.

Net radiation is the main energy source, contributing 50% of all energy available for melt, sensible heat contributing between 21% and 38%, latent heat 11% - 16%, and energy released by the sensible heat of rain less than 3%. This energy partitioning compares well to other investigations on glaciers in maritime climate.

The variations in the energy balance and melt rates were found to be more sensitive to variations in the sensible heat fluxes than to variations in net radiation.

Short-term high melt rates in August seem to occur when a cyclone traverses over northern Scandinavia from the northwest. Events of stable high-pressures over northern Scandinavia do not bring high melt rates, but are merely giving moderate or average melt rates.