Development of an Inexpensive Raindrop Size Spectrometer

Abstract

The deployment of weather radar, notably in mountainous terrain with many microclimates, requires the use of several or even many drop size spectrometers to provide confidence in the quantitative relation between radar reflectivity and rainfall. While there are several different commercial disdrometers available they are all expensive, large, or fragile, which militates against multiple deployment in the field. The design brief was for a reasonably accurate and sensitive, low-cost and rugged disdrometer to support field work. A design based on piezoceramic disks normally used in hydrophones is described. Calibration and typical field results are presented.