Abstract: A rainfall event in the Heihe River Basin was taken as an experimental case, and the mesoscale WRF3.1 was applied to study the sensitivity of different parameterized schemes to rainfall simulation. Effects of the microphysics, cumulus convection, land surface processes and the planetary boundary layer in the WRF parameterized schemes on the sensitivity of rainfall simulation in the Heihe River Basin were discussed, and the simulated results were validated with the observation data from 12 meteorological stations in the basin. The results showed that there was no single parameterized scheme to perform well in the simulation, and a combination of various parameterized schemes would be better. The results suggested that the center, value, distribution and extent of rainfall could be simulated well if the Mellor-Yamada-Janjic planetary boundary layer parameterized scheme and the Noah land surface process parameterized scheme were applied simultaneously. The results also suggested that the results simulated with Ferrier scheme were better than those with WSM3, WSM5 and Lin schemes. The sensitivity of cumulus convection parameterized scheme to the rainfall simulation was significantly lower than that of other schemes.

Key words: precipitation, physical process, parameterized scheme, numerical simulation, Heihe River Basin