| Summary: | This monograph presents results of research carried out using terrestrial photogrammetry over the period 1982—1985 and photointerpretation of aerial pictures taken in 1936, 1960 and 1961. Archival topographic maps and photogrammetric surveys have also been used. The state of the glaciers in South Spitsbergen has been examined (chapter 3). The analysis includes morphological type (tab. 1) and morphometric features (tab. 2). Based upon aerial photos taken in 1961 (fig. 7) the glacial zones, thermal regime have distinctly reduced volume over the period 1936—1961 (chapter 4, tab. 3). The diagram of changes in glacier thickness with the altitude shows the existence of kinematic waves (fig. 20—24), which in the case of Finsterwalderbreen, are the result of a surge. Werenskioldbreen, which terminates on land (chapter 5), and a grounded tidewater glacier Hansbreen (chapter 6) have been taken as examples to investigate glacier movement. A close relation between surface velocity and the amount of melt water flowing to the glacier bed (fig. 40—42) is observed. It supports the important role of basal slip for the glaciers of Spitsbergen. Maximum flow velocity is observed in mid-July, the first part of the ablation season (fig. 44 and 45). For land-terminated glaciers internal deformation is the dominant flow mechanism, accounting for more than 60% of the mean annual flow. Basal sliding decreases near the front. In the case of tidewater glaciers, basal sliding increases toward the front (at the terminus of Hansbreen 95% of surface velocity results from basal slip). Compressional flow dominates in the frontal part of glaciers terminated on land. Near the front of Werenskioldbreen, velocity vectors are emergent and velocity decreases gradually toward to the terminus. Current dynamics of Werenskioldbreen resemble the quiescent phase of a surging glacier. Movement of the frontal part of tidewater glaciers is tensional. Directions of Hansbreen flow vectors projected on a vertical plane are parallel to the surface and only close ...
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