RETRIEVAL OF RAIN INTENSITY BY MULTI FREQUENCY ACTIVE-PASSIVE REMOTE SENSING

Abstract

Development of the methods for remote sensing of liquid precipitation is currently central challenge for both practical application in different areas of agriculture and solution of theoretical tasks of the atmosphere physics. Method for retrieval of rain intensity by active-passive remote sensing based on double frequency radar and radiometer is considered. Expressions for active-passive remote sensing of rain are obtained in the form of system of three integral equations. Algorithm for solution of inverse problem by numerical methods is proposed which is based on the use of data base for received power of the double frequency radar and brightness temperature of the radiometer calculated by solution of direct problem of active-passive sensing for different values of drop size distribution parameters. Numerical simulation of active-passive remote sensing of liquid precipitation was performed for rain intensity up to 30 mm/h and for radar operating wavelengths 8.2 mm and 3.2 cm, and for radiometer wavelength 3.4 cm. It was shown that proposed algorithm allows to retrieve rain intensity with inaccuracy not more than 10 %.