Improvement test for simulation of vertical wind profile in MM5 and simulation analysis of meteorological fields in vertical cross-section

By adjusting the distribution of vertical sigma levels and increasing its number, the accuracy of computed wind, temperature and other meteorological fields are improved in near surface and upper levels in MM5 simulations. In particular, the density of vertical levels above 2000 meters is usually sparse compared with that near surface levels. Increasing the number of vertical levels above 2000 meters can improve greatly the accuracy of computed meteorological fields in upper levels, resulting in better analysis of weather phenomena such as the southwest low-level and high-level jets which have significant influence in the South China region in summer. The changes of vertical wind profile caused by updating of land use pattern are studied. The streamline fields are compared and analyzed in three vertical cross-sections in the Pearl River estuary. The updating land use patterns would lead to more realistic surface heat and vapor fluxes, resulting in more accurate upper atmosphere meteorological fields, such as the vertical wind profile, through vertical turbulent transport.