Estimation of Precipitation

Abstract

In the first section of this chapter we introduce the subject of estimation of precipitation using radar. Section 7.2 deals with the estimation of precipitation using measurements of reflectivity factor. Drop size measurements, Z-R relations and corrections needed for the effects of range, melting band and attenuation are discussed. Calibration with rain gauges is also dealt with in this section. In section 7.3, area-time integral methods are discussed. Section 7.4 deals with precipitation estimation using attenuation measurements. A treatment of multi-parameter methods follows in section 7.5. Combinations of reflectivity and attenuation, reflectivity and Doppler velocity at vertical incidence, dual wavelength measurements and polarisation parameters are considered. In section 7.6 we discuss the comparisons of radar and satellite measurements and the combined use of the two techniques. Finally, in section 7.7 we deal with the use of space-borne radar for precipitation measurement.