8 shows corrected coherence values. Coherence is almost stable for the whole time-series. Coherence bias was removed. With a given estimator of coherence, we conclude that correction of the coherence estimation bias is significant only in low coherence areas. Figure  9 illustrates backscattering coefficients and their deviations for several ground cover types.
Coherence provides a much better discriminator between different ground cover types.
Meteorological data provided by the Swiss Meteorological Office for the BernLiebefeld station. We show in figure 11 for one example within the time-series a combination of backscatter and coherence information. The correction of backscattering intensity and coherence estimation presented in this paper significantly enhances the value of these types of products. An accurate calibration of the backscattering coefficient and coherence considering elevation data is a fundamental requirement even for qualitative analysis. Coherence estimation benefits from DEM flattening of the interferogram, especially when a large number of samples are taken to improve the coherence estimate.