Stochastic generation of rainfall and an erosivity index to simulate erosive dynamics in central Tunisia

The proposed model is a stochastic generator of rainfall coupled to an empi rical model of rainfall erosivity. It is calibrated on a 15-year historical pluviographic database. Our objective is to develop a probabilistic simula tor that would permit the study of the erosive consequence of rains in time , while accumulating the effects over several years of the erosivity of con secutive rain spells, which are supposed to be proportional to the land ero sion, or to the suspended solid transport during the same period. This gene ration can be made over several years, and would permit us to avoid being c onstrained by sample size. The methodology is being used operationally, to reconstruct very long sets of rainy episodes with the objective of studying the cumulative effects of their erosivity in time. This approach can be se en as complementary to experimental approaches, reinforcing them and permit ting to obtain a better insight into the problem area of erosion.