Optimizing land surface parameters for simulating river runoff from 323 MOPEX-watersheds

Datasets have been prepared for 323 MOPEX-watersheds with an area of the order of 10–10⁴km²for simulating river runoff hydrograph with the use of the land surface model SWAP. Automatic optimization of model land surface parameters has been carried out for each watershed with the use of the SCE-UA algorithm for optimizing an objective function, which in this case has been presented by the Nash-Sutcliffe coefficient of efficiency estimated for daily runoff, under the condition that the systematic error of runoff simulation never exceeds 5%. The search of the optimal parameter values has been performed within specified ranges, which do not contradict to the physical meaning of appropriate parameters. The results of simulation of daily runoff obtained with the use of the optimized parameters are given.