Studying the Possibility of Precipitation Intensity Recovery from MTVZA-GYa Measurements

Abstract

In this paper, an algorithm for restoring the precipitation intensity over the ocean surface according to data from the MTVZA-GYa Russian microwave sounder is presented. The developed algorithm is based on the ALG’85 regression model in which the precipitation intensity is estimated using the scattering index on a high-frequency radiometric channel (~90 GHz). In this work, the scattering index is simulated based on MTVZA-GYa data and compared with GPM IMERG reanalysis data. To restore the precipitation intensity, it is proposed to use a fourth-degree polynomial. The quantitative estimates show that the RMS spread reaches 50%, and the correlation coefficient does not exceed 0.75. The qualitative comparison indicates a significant difference between the restored rain rate and the GPM IMERG data, as well as the presence of a shift of the precipitation area. As a result of the analysis, it is concluded that the incorrect convergence of the beams of the radiation patterns for different frequency channels of the MTVZA-GYa device might be one of the causes.