Interferometric observation of the phase centers displacements in forest covers in winter

Abstract:
Studies of seasonal variations of the scattered signal’s phase centers in forest covers are of importance for the better understanding of radiophysical properties of forest vegetation. Interferometric techniques provide possibility of centimeter-scale observations of the displacements. The data used in the study are on PALSAR-2 interferometric pairs acquired over Selenga river δ. According to double differential approach, interferometric phase of forests under study was corrected from the phase of nearby fields. Phase differences were corrected further in order to reduce phase delay in snowpack on the fields as well as in snow layers intercepted by trees. The phase centers displacements were discovered to be less than 2 cm for all observation intervals, and the displacement velocity decreases in the middle of winter.