Modeling and Interpretation of Simultaneous Horizontal and Vertical Polarization Transmit Radar Data. Part 2: Microphysical interpretation of S-Pol data

In this second article in a two-part work, S-Pol polarimetric data collected during TiMREX (Terraininfluenced Monsoon Rainfall Experiment) is analyzed and used to infer the storm microphysics. Both simultaneous horizontal (H) and vertical (V) transmit polarization data and fast alternating H and V transmit polarization data are used in the analysis. Dual-Doppler synthesis and sounding data characterize the storm environment and support the inferences. The small convective cells examined were likely electrified inferred from the observed negative Kdp (specific differential phase). Since Kdp values are high in ice and the accompanying Zdr values are close to 0 dB, it is inferred that there are two types of ice crystals present: 1) smaller aligned ice crystals that cause the Kdp signatures and 2) larger aggregates or graupel that cause the Zdr signatures. The inferences are supported with simulated ice crystal scattering calculations.