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Polarimetric radar measurements are sensitive to the size, shape and orientation of raindrops and provide information about drop size distribution (DSD), canting angle distribution and rain rate. In this paper, we propose and demonstrate a method for retrieving DSD parameters for calculating rain rate and the characteristic particle size. The DSD is assumed(More)
Raindrop size distribution (DSD) retrieval from remote radar measurements or from in situ disdrometer measurements is an important area of research. If the shape ( ) and slope ( ) of a three-parameter gamma distribution n(D) N0D exp( D ) are related to one another, as recent disdrometer measurements suggest, the gamma DSD model is simplified to a(More)
A new general polarimetric radar simulator for nonhydrostatic numerical weather prediction (NWP) models has been developed based on rigorous scattering calculations using the T-matrix method for reflectivity, differential reflectivity, specific differential phase, and copolar cross-correlation coefficient. A continuous melting process accounts for the(More)
The exponential distribution N(D) N0 exp( D) with a fixed intercept parameter N0 is most commonly used to represent raindrop size distribution (DSD) in rainfall estimation and in single-moment bulk microphysics parameterization schemes. Disdrometer observations show that the intercept parameter is far from constant and systematically depends on the rain(More)
This study proposes an approach that identifies and corrects for the vertical profile of reflectivity (VPR) by using Tropical Rainfall MeasuringMission (TRMM) precipitation radar (PR) measurements in the region of Arizona and southern California, where the ground-based Next Generation Weather Radar (NEXRAD) finds difficulties in making reliable estimations(More)
i Abstract A data assimilation system based on the ensemble square-root Kalman filter (EnSRF) is extended to include the additional capability of assimilating polarimetric radar variables. It is used to assess the impact of simulating additional polarimetric observations on convective storm analysis in an OSSE (Observing System Simulation Experiment)(More)
Dual-wavelength (K and X-band) radar measurements have shown promise in estimating the amount of liquid water in a cloud. By taking advantage of the attenuation by liquid water of the K -band signal as compared to X-band, the rangedifferentiated difference in reflectivity can be used to estimate the spatial distribution of cloud liquid water. One limitation(More)
A radar simulator for polarimetric radar variables, including reflectivities at horizontal and vertical polarizations, the differential reflectivity, and the specific differential phase, has been developed. This simulator serves as a test bed for developing and testing forward observation operators of polarimetric radar variables that are needed when(More)
[1] The impact of two different ways of modeling errors in simulated radar reflectivity data for observing system simulation experiments (OSSEs) with an ensemble Kalman filter is investigated. An error model different from the one used in earlier studies is introduced, and it specifies relative Gaussian-distributed errors in the linear domain of the(More)
A new triple-moment bulk microphysics scheme (BMP) described in Milbrandt and Yau (2005b, hereafter MY#, where # is the number of moments predicted) has been implemented in the Advanced Regional Prediction System (ARPS; Xue et al. 2003). The scheme predicts up to three moments of the size distribution for 2 categories of liquid (cloud droplets and(More)