Rain Measurement in Hilly Terrain with X-Band Weather Radar Systems: Accuracy of Path-Integrated Attenuation Estimates Derived from Mountain Returns

Abstract The authors recently showed that when attenuating wavelengths are used mountain returns may allow estimation of path-integrated attenuations (PIAs) between a ground-based weather radar and a given mountain, an application of the well-known Surface Reference Technique originally proposed for spaceborne radar configurations. This information proved to be valuable for the quantitative interpretation of X-band weather radar data in terms of rainfall rate for an urban hydrological application in Marseilles, France. In this paper, a further verification of this concept is presented with the comparison of mountain-derived PIAs and direct measurements obtained by means of a receiving antenna installed in the Balcons de Belledonne mountain ridge near Grenoble, France. Maximum PIAs in the range of 8–16 dB are obtained over the considered 9-km propagation path for various rain events observed between May and July 1997. A physical model of the mountain return power is developed leading to the formulation of ...