CGRG Bibliography of Canadian Geomorphology
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Author : Budkewitsch, P.; D’Iorio, M.A.; Vachon, P.W.; Lukowski, T.; Andersen, D.T.; and Pollard, W.H.
Date : 2000.
Title : Geomorphic, active layer and environmental changes detected in SAR scene coherence images.
Publication : Sixth Circumpolar Symposium on Remote Sensing of Polar Environments. Yellowknife June 12-14, 2000
Issue : Abstract.
Page(s) :
Abstract
Scene coherence images generated from repeat-pass or tandem satellite data can reveal terrain morphology, stability and highlight environmental changes. Where phase correlation is high, these areas are generally indicative of terrain stability, whereas areas of low phase coherence suggest changes in the scene has occurred. Data from ERS-1/-2 (1 to 12 day intervals) and RADARSAT-1 (24-day intervals) in the Canadian High Arctic were processed and scene coherence images generated from data pairs. When comparing the patterns in scene coherence, geomorphological features, such as drainage networks and the orientation of bedrock layering consistently appear from year to year. Large slope gradients exert important control on coherence loss due to viewing geometry. These are best distinguished from other sources of coherence loss in data taken over the shortest interval. Subtle topographic variations not observed due to geometrical viewing effects are frequently visible in scene coherence images due to environmental changes. These changes can be accounted for by the accumulation or migration of snowdrifts and compaction or recrystallisation of the snow pack on the ground surface. Although changes in the snow pack are different from year to year, general snow accumulation and wind patterns can be discerned. These features are more easily seen over longer intervals of time. Glacier flow, mass wasting and processes in the active layer causing expansion or cracking are other sources of temporal phase decorrelation that can be detected. In periglacial environments, scene coherence images can reveal greater geomorphological detail than can be seen in SAR images or other optical data. Radar coherence image can be an important tool for terrain monitoring, such as active layer mapping, especially during the winter months when snow cover, darkness or low illumination impede observation with optical remote sensing methods.
Bibliography of Canadian Geomorphology