ANALYSIS OF THE INFLUENCE OF DIFFERENT PARAMETERIZATION SCHEMES REPRESENTING THE PLANETARY BOUNDARY LAYER AND LAND SURFACE PROCESSES ON CONVECTION-PERMITTING SIMULATIONS OF A HEAVY RAINFALL EVENT ALONG MEI-YU FRONT
CHENYANG Rui-xue
LUO Ya-li
Abstract：Simulation sensitivities of a heavy rainfall event that occurred ahead of a mei-yu front on July 8,2007 to different parameterization schemes representing the planetary boundary layer (PBL)and land surface proces-ses are analyzed,using six 24-h convection-permitting simulations with the nested grid spacing of 1 .1 1 km.The results show that the different physics schemes mainly affect the location and intensity of heavy precipitation but with little effect on the location and pattern of the accumulative rain belt.The MYJ PBL scheme has better per-formance than the YSU PBL scheme that produces a smaller amount of precipitation.As for the three land sur-face parameterization schemes,the simulations utilizing the simple thermal diffusion scheme produce a larger a-mount of precipitation that agrees best with the observation,followed in turn by the Noah scheme and the RUC scheme.These sensitivities of the precipitation simulation are attributed to the differences of the simulated mois-ture and temperature profiles in the PBL caused by the different physics schemes,which leads to different con-vective available potential energy (CAPE)of the environmental inflow air to support the development of the rainy storm.The best-performing simulation produces a moister PBL and larger CAPE and hence stronger con-vective system and more abundant surface precipitation.
Keywords：heavy rainfall event along a mei-yu frontplanetary boundary layer parameterization schemesland surface parameterization schemesconvection-permitting simulationmesoscale convective system
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：12( 656-667 )