Sensitivities of deep convective systems on temperature stratification, surface parameters and orography

点击翻译按钮获取中文摘要

A novel cloud microphysics scheme is applied in the Lokalmodell (LM) of the German Weather Service (DWD) with cloud resolving resolution. The new scheme relies on balance equations for two moments of the size distributions, number as well as mass densities, of five types of liquid and ice hydrometeors. Besides improved descriptions of many cloud microphysical processes the two-moment scheme is able to distinguish between maritime and continental conditions which are known to largely control cloud microphysics and dynamics of convective clouds. Very many scenarios to be envisaged comprise idealized and real cases favourable to the development of convective clouds. The conditions taken into account range from a climatology of environmental parameters as stratification, humidity and wind profiles as well as to particular episodes. In assuming idealized and realistic orography the relevant processes and their mutual interactions determining precipitation initiation, evolution, timing and location are systematically investigated for the first time using the full capabilities of an operational limited-area NWP model. Additionally, crucial parameters decisive for precipitation evolution are assessed by a tangent-linear model and its adjoint applied to the cloud microphysics module.