Interaction of Diabatic Frontogenesis and Moisture Processes in Cold-Frontal Rain-Band
冷锋雨带中湿物理过程与非绝热锋生的相互作用

Three-dimensional simulation of cold-front rain-band (NCFR) associated with a straight cold front has been studied by use of a non-hydrostatic, full compressible storm-scale model (ARPS) including multi-phase microphysical parameterization. The dynamical and physical features of the frontal cloud de velopment have been well simulated and analyzed. It is in evidence that the frontal cloud is triggered by the updraft of the secondary frontal circulation. However, the long persistence of diabatic frontogenesis onlycan be attributed to positive feedback between the frontal baroclinicity and the prefrontal latent heat release. The simulations indeed demonstrate that the potential temperature gradient enhancement in front zone is strongly related with the re-distribution of cloud moisture, by the action of tilted updraft. In conse.quence, the splice of cooling and heating pool that is respectively created from the evaporation of cloud water and condensing / freezing of water vapor / rain droplet, wich is in favor of the strong contrast of cool and warm air mass across the frontal zone to diabatic frontogenesis.