DYNAMICAL AND MICROPHYSICAL RETRIEVAL FROM DOPPLER RADAR OBSERVATIONSUSING A CLOUD MODEL AND ITS ADJOINT - PART-II - RETRIEVAL EXPERIMENTSOF AN OBSERVED FLORIDA CONVECTIVE STORM

The variational Doppler radar analysis system developed in part I of t his study is tested on a Florida airmass storm observed during the Con vection and Precipitation Electrification Experiment. The 3D wind, tem perature, and microphysical structure of this storm are obtained by mi nimizing the difference between the radar-observed radial velocities a nd rainwater mixing ratios (derived from reflectivity) and their model predictions. Retrieval experiments are carried out to assimilate info rmation from one or two radars. The retrieved fields are compared with measurements of two aircraft penetrating the storm at different heigh ts. The retrieved wind, thermodynamical, and microphysical fields indi cate that the minimization converges to a solution consistent with the input velocity and rainwater fields. The primary difference between u sing single-Doppler and dual-Doppler information is the reduction of t he peak strength of the storm on the order of 10% when information fro m only one radar is provided. The comparison with aircraft data shows good agreement for the vertical velocity, buoyancy, and the water vapo r mixing ratio in terms of the general structure and strength of the f ields, but less agreement for the cloud water and rainwater field. The sensitivities of the retrieval system to the neglect of the time diff erence at each grid point in a radar volume and to the inclusion of th e background information at the initial time of the assimilation perio d are examined. Both show rather sensitive response. The experiments a lso show that the microphysical retrieval is quite sensitive to the re lation used to derive the rainwater mixing ratio from reflectivity obs ervations.