Multifrequency passive microwave observations of soil moisture in an arid rangeland environment

Abstract

A cooperative experiment was conducted by teams from the U.S. and U.S.S.R. to evaluate passive microwave instruments and algorithms used to estimate surface soil moisture. Experiments were conducted as part of an interdisciplinary experiment in an arid rangeland watershed located in the southwest United States. Soviet microwave radiometers operating at wavelengths of 2-25, 21 and 27 cm were flown on a U.S. aircraft. Radio frequency interference limited usable data to the 2-25 and 21 cm systems. Data have been calibrated and compared to ground observations of soil moisture. These analyses showed that the 21 cm system could produce reliable and useful soil moisture information and that the 2-25cm system was of no value for soil moisture estimation in this experiment.