TY - JOUR ID - TI - Estimation of Dual Polarization Weather Radar Variables AU - Dalia A. Mahmood PY - 2017 VL - 28 IS - 2 SP - 1 EP - 6 JO - Al-Mustansiriyah Journal of Science مجلة علوم المستنصرية SN - 1814635X 25213520 AB - Dual polarization weather radar has now become a widely used as instrument in meteorologicaloffices around the world because of its capability in distinguishing different precipitation typeand in improving the accuracy of quantitative precipitation estimation. The aim of this work isto estimate the polarimetry radar variables for radars of different frequency bands and studytheir behavior with rainfall rates.Calculations of polarimetry radar variables were made on the basis of several assumptions. Theresults showed that factors at horizontal and vertical polarization, ZH,V, ranges between 20 dBzrespectively, and more than 55 dBz for light rain and extreme heavy rain respectively, and radarreflectivity factor at horizontal ZH is greater than radar reflectivity factor at vertical ZV for allrainfall rates. The differential reflectivity, ZDR, also increases with increasing rainfall ratessince it is the difference between ZH and Zv.Calculations of specific differential attenuation indicated that X band radars are seriously attenuatedby rain and C band radars are less affected by rain. The specific differential attenuation, Sband radars is very small. In addition to this feature, the results showed that the differentialphase shift between return signals of horizontal and vertical polarizations for S band radars ismuch less than those for C and X band radars, and also, the results showed that the copolarizationcorrelation coefficient for S band the radars is much higher than those of C and Xbands.In order to investigate the accuracy of the calculated polarimetric weather radar variables performedin this research, real radar measurements were used for this purpose. Results indicatedthat the range of values for calculated polarimetric radar variables are very consistent with rangeof values for measured variables

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