Estimates of Precipitation Embryo Densities Using Measurements from an Aircraft Radar

Abstract

Determination of the habits (ice or water) and therefore the densities of particles whose images are acquired by 2D probes is often an ambiguous process. A Learjet's radar measurements of equivalent reflectivity factors from a range gate 1800 m ahead of the aircraft are compared to reflectivities calculated from images acquired by a 2D-C probe over a range of assumed particle densities from 0.2 to 1 g cm?3. Although the comparisons suffer from many uncertainties, such as the vast disparity between the volumes sampled by the 2D-C probe and the aircraft radar, the method does discriminate well between water drops or recently frozen riming water drops and low density graupel particles.