Reply on RC1

Abstract

Raindrop size distribution (DSD) observations during the passage of landfalling tropical cyclone NIVAR by impact (JWD) and laser (LPM and PARSIVEL) disdrometers are used to unveil the DSD characteristics in the eyewall, inner, and outer rainbands. Disdrometer measurements collected at the same location are used to study the effect of wind, measuring principle, and hardware processing on the DSDs and, in turn, on estimated rain integral and polarimetric parameters. The concentration of raindrops of diameters between 0.7 mm to 1.5 mm increases with rain rate (R) in all the regions of NIVAR, while the magnitude of the increase is high in the eyewall than in the inner and outer rainbands. The DSD characteristics reveal that for a given R, relatively large reflectivity (Z) and mass-weighted mean diameter (Dm) are found in the outer rainband and small Z, and Dm in the eyewall than in other regions of a TC. Raindrops of diameter 3-mm in size are observed frequently in inner and outer rainbands, while infrequent in the eyewall at R greater than 5 mm h−1. The DSDs and estimated rain integral and polarimetric parameters are distinctly different for various disdrometers at similar environmental conditions. Raindrops greater than 3 mm in size are infrequent in the JWD recordings while frequent in the LPM an PARSIVEL indicating JWD underestimates the size of the raindrops than LPM and PARSIVEL due to canting of raindrops in the presence of wind. The wind effect on the recorded DSD and estimated rain integral and polarimetric parameters are not uniform in various regions of NIVAR for different disdrometers as the measuring principle and hardware processing further influence these effects. Along with the differences in measured DSD spectra, the resonance effects at X-band for raindrops greater than 3-mm cause variations in the estimated polarimetric parameters between the disdrometers.