Modeling and Hindcasting of the Mass Balance of Werenskioldbreen (Southern Svalbard)

The authors propose a model of glacial mass balance based on correlations with meteorological observations and data from climate re-analysis. The minimum input data required include the following: average monthly temperature on the glacier and in its vicinity during summertime for a reference time period, average monthly air temperature, and average precipitation total at the nearest weather station or from re-analysis. This model was used to hindcast the mass balance and its components at Werenskioldbreen (southern Svalbard) over the period 1912-2005. The hindcast specific mass balance was then used to estimate the change in the thickness of the snout of Werenskioldbreen over the period 1958-1990. These results were compared with results obtained using a cartographic method. Comparing the topographic maps, the glacier front lowered 28.7 m on average over 32 years. The average difference in the calculation of the change in glacier thickness between these two methods amounted to 3.7 m (based on meteorological data) and 0.2 m (using ERA-40). The discrepancy of less than 13% confirmed that the method is a reasonably accurate way of predicting past glacier mass balance. The proposed method can find a broad application in hindcasting the mass balances of small Svalbard glaciers where observation data are scarce or nonexistent.