Estimation of the snowpack parameters from the data obtained by a satellite-borne multi-frequency microwave radiometer

The Advanced Earth Observing Satellite-II (ADEOS-II) equipped with the Advanced Microwave Scanning Radiometer (AMSR) will be launched in 2000 by NASDA of Japan. The AMSR is a multi-frequency microwave radiometer, which captures 14 different micro/millimeter-wave noises in the wide frequency band, radiated from the Earth and atmosphere. The satellite microwave radiometer has the potential for obtaining macroscopic information concerning snowpack characteristics. Data processing methods and results analysis are required. The authors developed a method for statistical processing of obtained by the Microwave Scanning Radiometer (MSR) on the Marine Observation Satellite-1 (MOS-I), and tried to interpret the results of the analysis and estimate the snowpack parameters in Hokkaido region. As the MSR received microwave noises at two contiguous frequencies (23.8 and 31.4 GHz), there were some difficulties or limitations for estimating the snowpack parameters. The objective of this paper is the development of a data processing method to estimate the snowpack parameters such as depth and grain size using the data obtained by the AMSR on ADEOS-II. Instead of the brightness temperature observed by the AMSR, the microwave emissivities at five selected frequencies of the AMSR is analyzed using a snowpack model which had been used for the analyses of the data obtained by the MSR on MOS-l. Using the results of the model analysis, the efficiency and accuracy of the method on the snowpack is presented