Abstract

Copyright 1996 by the American Geophysical Union.Repeat-pass, interferometric, radar observations of tropical rain-forest collected by the Shuttle Imaging Radar C in the state of Rondonia, Brazil, reveal signal coherence is destroyed at C-band in the forest, whereas L-band radar signals remain strongly coherent over the entire landscape. At L-band, the rms difference in inferred topographic height between the forest and adjacent clearings is 5 m, equivalent to the height noise. Atmospheric delays are large, however, forming kilometer-sized anomalies with a 1.2-cm rms one way. Radar interferometric studies of the humid tropics must therefore be conducted at long radar wavelengths, with kilometric baselines or with two antennas operating simultaneously.