The Impact of Size Sorting on the Polarimetric Radar Variables

AbstractDifferential sedimentation of precipitation occurs because heavier hydrometeors fall faster than lighter ones. Updrafts and vertical wind shear can maintain this otherwise transient size sorting, resulting in prolonged regions of ongoing particle sorting in storms. This study quantifies the impact of size sorting on the S-band polarimetric radar variables (radar reflectivity factor at horizontal polarization ZH, differential reflectivity ZDR, specific differential phase KDP, and the copolar cross-correlation coefficient ρhv). These variables are calculated from output of two idealized bin models: a one-dimensional model of pure raindrop fallout and a two-dimensional rain shaft encountering vertical wind shear. Additionally, errors in the radar variables as simulated by single-, double-, and triple-moment bulk microphysics parameterizations are quantified for the same size sorting scenarios.Size sorting produces regions of sparsely concentrated large drops with a lack of smaller drops, causing ZDR ...

[1]  P. Chilson,et al.  Microphysical retrievals from simultaneous polarimetric and profiling radar observations , 2009 .

[2]  Jidong Gao,et al.  Impact of CASA Radar and Oklahoma Mesonet Data Assimilation on the Analysis and Prediction of Tornadic Mesovortices in an MCS , 2011 .

[3]  Guifu Zhang,et al.  Comparison of Polarimetric Radar Drop Size Distribution Retrieval Algorithms , 2004 .

[4]  Roy Rasmussen,et al.  Melting and Shedding of Graupel and Hail. Part I: Model Physics , 1987 .

[5]  Henri Sauvageot,et al.  Multimodal Raindrop Size Distributions , 2000 .

[6]  Carlton W. Ulbrich,et al.  Microphysics of Raindrop Size Spectra: Tropical Continental and Maritime Storms , 2007 .

[7]  A. Ryzhkov,et al.  Polarimetric Tornado Detection , 2005 .

[8]  R. C. Srivastava,et al.  Doppler radar characteristics of precipitation at vertical incidence , 1973 .

[9]  The Microphysical Structure and Evolution of Hawaiian Rainband Clouds. Part I: Radar Observations of Rainbands Containing High Reflectivity Cores , 1997 .

[10]  Alexander V. Ryzhkov,et al.  Storm-Relative Helicity Revealed from Polarimetric Radar Measurements , 2009 .

[11]  J. S. Marshall,et al.  PRECIPITATION TRAJECTORIES AND PATTERNS , 1953 .

[12]  Alexander V. Ryzhkov,et al.  Polarimetric Signatures in Supercell Thunderstorms , 2008 .

[13]  R. McTaggart-Cowan,et al.  Sedimentation-Induced Errors in Bulk Microphysics Schemes , 2010 .

[14]  C. Snyder,et al.  A Multicase Comparative Assessment of the Ensemble Kalman Filter for Assimilation of Radar Observations. Part I: Storm-Scale Analyses , 2009 .

[15]  C. Snyder,et al.  Assimilation of Simulated Doppler Radar Observations with an Ensemble Kalman Filter , 2003 .

[16]  Jerry M. Straka,et al.  Assimilation of Simulated Polarimetric Radar Data for a Convective Storm Using the Ensemble Kalman Filter. Part II: Impact of Polarimetric Data on Storm Analysis , 2008 .

[17]  Roger M. Wakimoto,et al.  Radar and Atmospheric Science: A Collection of Essays in Honor of David Atlas , 2003 .

[18]  J. Marshall,et al.  THE EFFECT OF WIND SHEAR ON FALLING PRECIPITATION , 1955 .

[19]  Guifu Zhang,et al.  Drop Size Distribution Retrieval with Polarimetric Radar: Model and Application , 2004 .

[20]  Alexander V. Ryzhkov,et al.  Polarimetric Radar Observations and Interpretation of Co-Cross-Polar Correlation Coefficients , 2002 .

[21]  W. Hitschfeld.  The Motion and Erosion of Convective Storms in Severe Vertical Wind Shear. , 1960 .

[22]  Robert D. Palmer,et al.  Investigation of Non-Gaussian Doppler Spectra Observed by Weather Radar in a Tornadic Supercell , 2009 .

[23]  M. Sachidananda,et al.  Rain Rate Estimates from Differential Polarization Measurements , 1987 .

[24]  Jerry M. Straka,et al.  Bulk Hydrometeor Classification and Quantification Using Polarimetric Radar Data: Synthesis of Relations , 2000 .

[25]  Matthew,et al.  MICROPHYSICAL SIZE SORTING REVEALED BY DUAL-POLARIZATION DOPPLER RADAR , 2008 .

[26]  R. Rasmussen,et al.  Melting and Shedding of Graupel and Hail. Part III: Investigation of the Role of Shed Drops as Hail Embryos in the 1 August CCOPE Severe Storm , 1987 .

[27]  Louis J. Wicker,et al.  Ensemble Kalman Filter Assimilation of Radar Observations of the 8 May 2003 Oklahoma City Supercell: Influences of Reflectivity Observations on Storm-Scale Analyses , 2011 .

[28]  Alexander D. Schenkman,et al.  The Analysis and Prediction of the 8–9 May 2007 Oklahoma Tornadic Mesoscale Convective System by Assimilating WSR-88D and CASA Radar Data Using 3DVAR , 2011 .

[29]  Guifu Zhang,et al.  Experiments in Rainfall Estimation with a Polarimetric Radar in a Subtropical Environment , 2002 .

[30]  M. Xue,et al.  Analysis of a Tornadic Mesoscale Convective Vortex Based on Ensemble Kalman Filter Assimilation of CASA X-Band and WSR-88D Radar Data , 2011 .

[31]  J. Marshall,et al.  THE DISTRIBUTION OF RAINDROPS WITH SIZE , 1948 .

[32]  D. Stensrud,et al.  Comparison of Single-Parameter and Multiparameter Ensembles for Assimilation of Radar Observations Using the Ensemble Kalman Filter , 2012 .

[33]  I. Zawadzki,et al.  Equilibrium raindrop size distributions in tropical rain , 1988 .

[34]  V. Plank,et al.  DROP-SIZIE HISTORY DURING A SHOWER , 1953 .

[35]  A. Ryzhkov,et al.  Polarimetric Radar Observation Operator for a Cloud Model with Spectral Microphysics , 2011 .

[36]  L. Carey.  Precipitation properties of a cool-season tornadic storm inferred from C-band dual-polarimetric radar and 2D-video disdrometer observations , 2010 .

[37]  Mingjing Tong,et al.  Ensemble kalman filter assimilation of doppler radar data with a compressible nonhydrostatic model : OSS experiments , 2005 .

[38]  M. Yau,et al.  A Multimoment Bulk Microphysics Parameterization. Part I: Analysis of the Role of the Spectral Shape Parameter , 2005 .

[39]  H. R. Pruppacher,et al.  A wind tunnel investigation of the internal circulation and shape of water drops falling at terminal velocity in air , 1970 .

[40]  On the selection of prognostic moments in parametrization schemes for drop sedimentation , 2008 .

[41]  M. Xue,et al.  3DVAR and Cloud Analysis with WSR-88D Level-II Data for the Prediction of the Fort Worth, Texas, Tornadic Thunderstorms. Part I: Cloud Analysis and Its Impact , 2006 .

[42]  A. Shapiro.  Drag-Induced Transfer of Horizontal Momentum between Air and Raindrops. , 2005 .

[43]  Alexander V. Ryzhkov,et al.  The Hydrometeor Classification Algorithm for the Polarimetric WSR-88D: Description and Application to an MCS , 2009 .

[44]  V. N. Bringi,et al.  Potential Use of Radar Differential Reflectivity Measurements at Orthogonal Polarizations for Measuring Precipitation , 1976 .

[45]  E. Kessler.  On the distribution and continuity of water substance in atmospheric circulations , 1969 .

[46]  M. Yau,et al.  A Multimoment Bulk Microphysics Parameterization. Part II: A Proposed Three-Moment Closure and Scheme Description , 2005 .

[47]  James E. Dye,et al.  The Mechanism of Precipitation Formation in Northeastern Colorado Cumulus III. Coordinated Microphysical and Radar Observations and Summary , 1974 .

[48]  Juanzhen Sun,et al.  A Velocity Dealiasing Technique Using Rapidly Updated Analysis from a Four-Dimensional Variational Doppler Radar Data Assimilation System , 2010 .

[49]  Guifu Zhang,et al.  Simulations of Polarimetric Radar Signatures of a Supercell Storm Using a Two-Moment Bulk Microphysics Scheme , 2010 .

[50]  A. Seifert,et al.  Evolution of rain water profiles resulting from pure sedimentation: Spectral vs. parameterized description , 2001 .

[51]  Alexander V. Ryzhkov,et al.  Interpretation of Polarimetric Radar Covariance Matrix for Meteorological Scatterers: Theoretical Analysis , 2001 .

[52]  P. Kollias,et al.  Raindrop sorting induced by vertical drafts in convective clouds , 2001 .

[53]  B. Ferrier,et al.  A Double-Moment Multiple-Phase Four-Class Bulk Ice Scheme. Part I: Description , 1994 .

[54]  H. Pruppacher,et al.  A Semi-Empirical Determination of the Shape of Cloud and Rain Drops , 1971 .

[55]  Ming Hu,et al.  3DVAR and Cloud Analysis with WSR-88D Level-II Data for the Prediction of the Fort Worth, Texas, Tornadic Thunderstorms. Part II: Impact of Radial Velocity Analysis via 3DVAR , 2006 .

[56]  Alexander V. Ryzhkov,et al.  The Impact of Evaporation on Polarimetric Characteristics of Rain: Theoretical Model and Practical Implications , 2009 .

[57]  Daniel T. Dawson,et al.  Comparison of Evaporation and Cold Pool Development between Single-moment and Multi-moment Bulk Microphysics Schemes in Idealized Simulations of Tornadic Thunderstorms , 2009 .

[58]  Carlton W. Ulbrich,et al.  Path- and Area-Integrated Rainfall Measurement by Microwave Attenuation in the 1–3 cm Band , 1977 .

[59]  P. Hobbs,et al.  Super‐large raindrops , 2004 .

[60]  L. A. Dean,et al.  DROP-SIZE HISTORY DURING A SHOWER , 1954 .

[61]  V. N. Bringi,et al.  Drop Axis Ratios from a 2D Video Disdrometer , 2005 .

[62]  R. Gunn,et al.  THE TERMINAL VELOCITY OF FALL FOR WATER DROPLETS IN STAGNANT AIR , 1949 .

[63]  C. Ulbrich.  Natural Variations in the Analytical Form of the Raindrop Size Distribution , 1983 .

[64]  Alexander V. Ryzhkov,et al.  A Combined Wind Profiler and Polarimetric Weather Radar Method for the Investigation of Precipitation and Vertical Velocities , 2009 .

[65]  Alexander V. Ryzhkov,et al.  Analysis of Video Disdrometer and Polarimetric Radar Data to Characterize Rain Microphysics in Oklahoma , 2008 .

[66]  A. Ryzhkov.  Polarimetric characteristics of melting hail at S and C bands , 2009 .

[67]  Guifu Zhang,et al.  A method for estimating rain rate and drop size distribution from polarimetric radar measurements , 2001, IEEE Trans. Geosci. Remote. Sens..

[68]  L. Battan.  Rain Resulting from Melting Ice Particles , 1977 .

[69]  Robert M. Rauber,et al.  A Mechanism for Giant Raindrop Formation in Warm, Shallow Convective Clouds , 1991 .

[70]  E. Mansell.  On Sedimentation and Advection in Multimoment Bulk Microphysics , 2010 .