Airborne Remote Sensing of the Super-Cooled Water and Temperature Environment

We propose to test a new method for remote passive detection of hydrometeors (cloud liquid water droplets, drizzle, rain, hail, and snow) from an aircraft. The method uses an advanced radiometer to measure differences between horizontal and vertical polarization of microwave radiation. The polarization is influenced by hydrometeor shape and the anisotropy of the illuminating flux. This allows discrimination between liquid water and ice crystals. Radiometrics Corporation conceived the new method and is applying for patent. Based on preliminary simple modeling, the capability of the new method appears fairly certain. We propose to confirm our preliminary results with more rigorous modeling. We also have conceived of three concepts to obtain range information on icing conditions. The capabilities of the concepts are uncertain and we propose modeling and testing. In addition, we propose to explore the performance of a method for passive airborne measurement of atmospheric temperature structure. This method is based on a highly accurate ground-based radiometric temperature profiling method that has recently emerged from Russia. Knowledge of temperature structure is important for prediction of icing conditions and turbulence.