Preliminary evaluation of polarimetric parameters from a new dual-polarization C-band weather radar in an alpine region

摘要

The first operational weather radar with dual polarization capabilities wasrecently installed in Austria. The use of polarimetric radar variables risesseveral expectations: an increased accuracy of the rain rate estimationcompared to standard Z-R relationships, a reliable use of attenuationcorrection methods, and finally hydrometeor classification. In this studythe polarimetric variables of precipitation events are investigated and theoperational quality of the parameters is discussed. For the new weatherradar also several polarimetric rain rate estimators, which are based on thehorizontal polarization radar reflectivity, , the differentialreflectivity, , and the specific differential propagation phaseshift, , have been tested. The rain rate estimators are furthercombined with an attenuation correction scheme. A comparison between radarand rain gauge indicates that based rain rate algorithms show animprovement over the traditional Z-R estimate. based estimates donot provide reliable results, mainly due to the fact, that the observed parameters are quite noisy. Furthermore the observed rain rates aremoderate, where is less significant than in heavy rain.