Retrieval of Vertical Profiles of Liquid Water and Ice Content in Mixed Clouds from Doppler Radar and Microwave Radiometer Measurements

Abstract

Abstract A new method to retrieve vertical profiles of liquid water content Mw(z), ice water content Mi(z), and ice particle size distribution Ni(D, z), (where D is the ice particle size and z the vertical coordinate) in mixed nonprecipitating clouds using the observations of a zenith-viewing Doppler radar and of a microwave radiometer is proposed. In this method, the profile of the vertical air velocity deduced from Doppler radar measurements is used to describe the rate of production by the updrafts of water. vapor in excess of saturation with respect to ice. Using a Zi − Mi power-law relation with an unknown linear parameter (let αi, be this parameter) and initially assuming that Zw is negligible with respect to Zi, (where Zw and Zi are the radar reflectivity factors of liquid water and ice particles respectively), the measured radar reflectivity factor profile Zm (≈ Zi) is inverted to estimate Ni(D, z). From Ni(D, z), the profile of the rate of water vapor that can be consumed by pure deposition on ic...