摘要:利用2006年第4号强热带风暴“碧利斯”登陆过程的高分辨率数值模拟资料，结合三维地面降水诊断方程和降水效率公式，研究了“碧利斯”登陆后引发的局地暴雨过程，重点分析了此次局地暴雨过程的降水强度和降水效率及其与宏微观物理因子的联系。结果表明，降水强度越强，降水效率越高，但两者并非一一对应的线性关系，随着降水强度增大，降水效率增高的趋势逐渐变缓；伴随暴雨系统快速发展，降水强度和降水效率均显著增强，而主要降水源/汇项的时间变化要复杂得多；暴雨发生前时段与发生时段降水物理过程存在显著差异，发生前，较明显的水汽辐合显著加湿局地大气，并通过微物理转化支持降水云系发展，液相水凝物辐合对降水云系快速发展贡献明显，固相水凝物辐合贡献不显著，较强的“云滴与雨滴碰并（Pracw）”微物理过程同液相水凝物明显辐合可能有直接关系，“霰融化造成雨滴增长（Pgmlt）”仅为Pracw的27%，发生时段，进一步明显加强的水汽辐合依旧是主要降水来源，而汇项发生了明显变化，同时，微物理转化过程与发生前比更活跃，尤其是Pracw和Pgmlt，其中，Pgmlt增强更明显，其值接近Pracw的50%。
关键词:降水强度/
降水效率/
局地暴雨过程/
登陆热带气旋
Abstract:By using high-resolution simulation data of Bilis (0604) and three-dimensional surface precipitation and precipitation efficiency (LSPE) equations, precipitation rate (Ps) and LSPE as well as their relations to macroscopic and microphysical factors were analyzed.The results show that LSPE increases with Ps, but the relationship between them is not linear with one-to-one correspondence.With increased Ps, the increasing tendency of LSPE slowed down gradually.Following the rapid development of the torrential rainfall system, both Ps and LSPE increased distinctly, while temporal changes in the main source/sink terms of the surface rainfall were much more complicated.Physical processes associated with surface rainfall before the occurrence of the torrential rainfall differed a lot from those associated with the torrential rainfall.Before the occurrence, the water vapor convergence mainly moistened the local atmospheric column and also partially contributed to the development of the rainfall cloud system through microphysical processes.The convergence of liquid-phase hydrometeors contributed more to the rapid development of the rainfall cloud system compared to ice-phase hydrometeors.The strong microphysical process, i.e. "accretion of cloud water by rainwater (Pracw)", may be directly related to the distinct convergence of liquid-phase hydrometeors.The ratio of the microphysical processes, i.e. "melting of graupel (Pgmlt)" to Pracw, was about 27%.During the heavy rainfall period, the distinctly enhanced moisture convergence was still the primary water vapor source for surface rainfall, but the sink terms for surface rainfall changed a lot.Meanwhile, microphysical conversion processes became more vigorous, especially Pracw and Pgmlt.The ratio of Pgmlt to Pracw was nearly 50%.
Key words:Surface rain rate/
Precipitation efficiency/
Local heavy precipitation event/
Landfalling tropical cyclone
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