In: Wagner W., Szekely, B. (eds.): ISPRS TC VII Symposium - 100 Years ISPRS, Vienna, Austria, July 5-7, 2010, IAPRS, Vol. XXXVIII, Part 7B 
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canal at the right top of the image and a wetland in between 
them. Most of the rest of the scene is covered by forest. 
4.2 Results 
The high degree of vegetation cover and the time difference of 
three month between the acquisitions result in an overall low 
coherence due to temporal decorrelation which is typical for 
temperate and tropical regions. Following, the emphasis for the 
change indicator was put on the intensity ratio. The detection 
mask overlaid on the first image is shown in Figure 4. The red 
pixels signify areas where the backscatter reduced and the blue 
ones stand for an increased backscatter. 
Different kinds of changes are detected within this scene. For 
example on the left bottom of the subset a clearing of the forest 
was conducted, which is clearly visible in the changing 
backscatter of the two images. Also new constructions are 
detected in the north of the buildings belonging to the airport. 
Regions where varying soil moisture in the wetland caused a 
different backscatter, as well as temporarily present objects, like 
e.g. wagons on the runway and ships on the sea appear also in 
Figure 4: Change detection mask; red: backscatter 
reduced, blue: backscatter increased. 
Figure 2: TerraSAR-X acquisition of 25.01.2009. 
Figure 3: TerraSAR-X acquisition of 12.04.2009. 
Figure 5: Land cover classification of TerraSAR-X 
derived features (25.01.2009). 
Figure 6: Detected and assessed changes.