Ice water path estimation and characterization using passive microwave radiometry

An ice phase characterization perhaps represents a more inherently retrievable property from a combination of scattering-based channels above 37 GHz than the underlying rainfall. Model computations of top-of-atmospheric microwave brightness temperatures T_B from layers of precipitation-sized ice of variable bulk density and ice water content (IWC) are presented. The 85-GHz T_B is shown to depend essentially on the ice optical thickness, while the possibility of using the 37- and 85-GHz brightness temperature difference ΔT_B to estimate the integrated ice water path (IWP) is investigated. The results demonstrate the potential usefulness of using scattering-based channels to characterize the ice phase and suggest a top-down methodology for retrieval of cloud vertical structure and precipitation estimation from multifrequency passive microwave measurements. -from Authors