Remote sensing of rainfall parameters by laser scintillation correlation method-complete equation and numerical simulation

Remote sensing of rainfall parameters by using laser scintillation effect, originally proposed by Wang et al. is a unique approach for getting rainfall rate and raindrop size distribution with excellent temporal and spatial representativeness. In this paper, we review Wang's work, point out the weakness of their basic equations, then establish a complete remote sensing equation in which the observable quantity, the scintillation of light intensity is used. The relationships between the rainfall parameters and the spatial-temporal correlation function of light scintilla tion are systematically discussed. Numerical investigations show that this equation gives at least four different ways to obtain the rainfall rate, and the kernel functions for raindrop size distribution are of excellent resolution. At last, the retrieval scheme of the drop size distribution is discussed.