A distributed hydrological model adapted to the automatic calibration of parameters

The calibration of large distributed conceptual daily rainfall-runoff models requires lengthy computations that can prevent the use of automatic optimization methods. A new distributed model (MDOR) with a faster transfer algorithm is developed to overcome this limitation. The new aspects of this model are the aggregation of spatial units in fewer supra-units and the summation of runoff production directly at the outlet taking into account the routing time-lags, the time-lags being evaluated independently prior to the simulation. Automatic calibration tests demonstrate the ability to perform high precision calibration of MDOR involving several thousand annual simulations within reasonable computation time limits.