The GRAPES-TCM is used to make prediction experiments for Typhoon Muifa (1109). Thirty six experiments are made and the integral time is 72 h. By experiments, the influence of two boundary layer parameterization schemes—MRF scheme and YSU scheme on typhoon prediction under different circumstances is analyzed.
Theexperiment results show that Muifa track and intensity are both sensitive to the boundary layer scheme’s change. The sensitivity magnitude is related to some other factors such as convection parameterization scheme and typhoon initial intensity. The intensity sensitivity is greater than the track sensitivity. For weak typhoon, the track and intensity predictions with YSU scheme are overall better than that with MRF scheme. For strong typhoon, between the two boundary layer schemes, MRF scheme’s track prediction is better. Which scheme’s intensity prediction is better is related to the choice of the convection scheme. In all cases, Muifa intensity with YSU scheme is obviously stronger than that with MRF scheme, and the precipitation and the sensible heat flux and latent heat flux with YSU scheme are all greater than that with MRF scheme. When the boundary layer scheme is YSU scheme, the turbulence mixing in the boundary layer is more powerful, which leads to more sensible heat flux and more latent heat flux. More latent heat flux leads to more precipitation which releases more latent heat. More latent heat release and more sensible heat flux lead to stronger typhoon.