ESTIMATION OF VERTICAL DISTRIBUTION OF RELATIVE HUMIDITY USING SATELLITE DATA

In this paper,an attempt has been made to find out the vertical distribution of RH at levels of 850,700 and 500 hPa by using satellite-derived radiation parameters (i.e.,albedo,outgoing longwave fluxes,absorbed solar radiation and net radiation).For this purpose,multiple regression equations are derived from MONEX-79 upsonde and dropsonde data over the Arabian Sea for the period 11-20 June 1979.Satellite-estimated RH fields have been compared with ECMWF RH fields obtained from FGGE level ⅢB data.The RMS error and error variance for satellite-estimated RH fields have been found to be less than for those of ECMWF.Satellite-estimated isohygric patterns show good agreement with the cloudiness patterns of GOES satellite,whereas ECMWF isohygric patterns do not show much resemblance with the cloudiness patterns.The results of the study suggest that satellite-estimated RH fields could be more useful than ECMWF RHfields and they can be used with some confidence in NWP models.