A NEW METHOD TO ESTIMATE RAINFALL INTENSITY FROM RADAR REFLECTIVITY CONSIDERING THE ALTITUDE VARIATION OF RAINDROP SIZE DISTRIBUTION

Abstract

The method to estimate the raindrop size distribution at altitude covering with radar beam from the one observed at the ground is discussed and by this new method, the method to estimate rainfall intensity from radar reflectivity factor is proposed. The equations to estimate the raindrop size distribution at the upper altitude from the one at the ground are derived from one dimensional simulation of raindrop collision/breakup. The new model proposed in this paper can estimate rainfall intensity observed by a radar raingauge more accurately.