1 Background - mountain.PROJECTS

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TURKU UNIVERSITY DEPARTMENT OF GEOGRAPHY PUBLICATIONS B Nr 4modes of glacier dynamics, e.g. 1) incremental (slow and moderate) changes due to ablation /accumulation processes, 2) periodic rheological fluctuations of the glacier surface, e.g. thosedue to kinematic waves, 3) abrupt / catastrophic changes of glacier borders / surface due toglacier surges, calving, snow- and ice-avalanches etc.Technical progressAn experimental data set included all necessary Austrian and Norwegian topographic maps,airborne orthoimages from national survey administrations, multitemporal recordsdocumenting the rate of glacier ice flow, the multidate set of airborne laser scanning data,ASTER and LANDSAT multitemporal images, five pairs of stereoscopic IKONOS andEROS images and seven pairs of ERS-1/2 SAR interferograms taken under favorable weatherconditions in 1985 - 2003. The image data were processed using the 8.6 Erdas Imagine andin-house software packs. Cartographic styling, drafting, scribing and editing were performedusing the ArcInfo 8.1 and FreeHand 10 software. Some developments in cartographic designand symbolisation contributed their share to the aesthetic appearance of map sheets. As aresult 21 full-value maps showing the distribution of glacier zones and strain rates, icevelocities, glacier marginal and surficial (elevation) changes in both test sites at differentscales ranging from 1:25 000 to 1:100 000 were compiled, printed and verified on a costeffectivebasis, thus completing the whole processing chain. Several examples of mapsshowing glacier changes in both test sites are given in Figures 30 - 35. All draft map sheetswere tested by an independent expert in order to appraise their horizontal and verticalaccuracy, and information contents. Basic ground control surveys for the image-basedmapping were performed during field campaigns in Augusts 2002 and 2003.Figure 30. Map of Engabreen elevation changes (2001-2002) defined by airborne laser scanner data.A significant retreat of glacial termini and general lowering of the glacier surface wasdetected in the study areas in the past five years (Figure 33). The maximum losses of glacierice were recorded at termini of Fingerbreen (1.4 km²), Hintereisferner (0.37 km²),Guslarferner (0.16 km²), Vernaglwandferner (0.13 km²) and Storglombreen (0.11 km²)glaciers. Local changes in area amounting to 20% (Guslarferner), 14% (Vernaglwandferner)48
PETRI PELLIKKA AND KARI KAJUUTTI (ED)and 10% (Fingerbreen) of the total glacier area can be considered as more than significanteven for these relatively large valley glaciers in Europe. Present estimations of glacierdynamics in the OMEGA test sites are believed to be both expedient and useful for furthermultidisciplinary studies in European glacial areas.Figure 31. Satellite image map showing the distribution of main glacier zones at Hintereisferner on20.08.20021312[cm /day]annual 95/96DINSAR II.961110DINSAR IV.96GINSAR9876543210[Point ID]72 76 70 71 69 75 68 581 66 74 65 56 64 571 681 57 51 45 44 781 50 42 38 100 34 30 981 27 22 19 12 13Figure 32. Interferometric velocities versus average annual velocities 1995/96 on Hintereisferner.49
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1 Background - mountain.PROJECTS

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