Dynamical influence of microphysics in tropical squall lines: A numerical study

Based on environmental conditions of the 22 and 23 June squall lines during the Convection Profonde Tropicale in 1981 (COPT81) experiment in West Africa, a series of numerical simulations are performed with a two-dimensional nonhydrostatic cloud model to examine the dynamical effect of microphysics in tropical squall lines. The role of ice-phase microphysics strongly depends on ambient conditions. For the environment of strong convective instability, the ice phase is important regarding the system-scale structure but is not important to the convective-scale dynamics. On the other hand, the ice influence is crucial to the squall-line convective system if the environment has a weak convective instability and is almost saturated at low levels.