Joint probability distribution of annual maximum storm peaks and amounts as represented by daily rainfalls

A procedure is presented for using the bivariate normal distribution to des cribe the joint distribution of storm peaks (maximum rainfall intensities) and amounts which are mutually correlated. The Box-Cox transformation metho d is used to normalize original marginal distributions of storm peaks and a mounts regardless of the original forms of these distributions. The transfo rmation parameter is estimated using the maximum likelihood method. The joi nt cumulative distribution function, the conditional cumulative distributio n function, and the associated return periods can be readily obtained based on the bivariate normal distribution. The method is rested and validated u sing two rainfall data sets from two meteorological stations that are locat ed in different climatic regions of Japan. The theoretical distributions sh ow a good fit to observed ones.