摘要
利用卫星资料、NCEP资料以及AREM模式输出资料,对发生在2008年10月中旬海南岛一次大暴雨过程进行了中尺度数值模拟分析。分析结果表明:AREM模式较好地模拟了本次大暴雨过程,当初始资料选取NCEP资料时模拟效果最佳;sθe等值线密集区以及位涡梯度最大区与暴雨中心相对应;暴雨中心700 hPa以下低层对应条件对称不稳定,其上至600 hPa为对流不稳定;条件对称不稳定对其上空的对流不稳定有触发作用;对热源〈Q1〉和水汽汇〈Q2〉分析得出,大值区与降水分布基本一致,凝结潜热的释放对大暴雨过程有反馈作用;位温垂直平流项对Q1起决定性作用,位温局地变化项及水平平流项对Q1的贡献不大。在Q2诸分量中,比湿水平平流项和垂直平流项共同作用于Q2,比湿局地变化项影响较小。
By use of satellite,NCEP reanalysis data and AREM model data,a heavy rain event in Hainan province during October 2008 is analyzed.Results show that the AREM model can effectively simulate the event,especially when NCEP reanalysis data is chosen as the model initial input data.The heavy rain is located near the intensive belt of θse and the maximum potential vorticity gradient on the zero line of MPV1.The conditional symmetry instability is constructed at 700 hPa and the convection instability is constructed at 700 hPa-600 hPa in the high-value region of heavy rain.The conditional symmetry instability is the cause of the declining and ascendant air current in the lower layers and leads to the convection instability in the higher layers than 700 hPa.The high value region of 〈Q1〉 and 〈Q2〉 is basically consistent with the heavy rainfall region.There is a feedback reaction of release of latent energy on the process of heavy rain.The vertical advection of θ plays a key role in Q1,the local variation and the horizontal advection of θ don＇t have serious impact on Q1.The horizontal advection and vertical advection of q play a main role in Q2,but the local variation of q impacts Q2 only a little.
出处
《气象科学》
CSCD
北大核心
2010年第4期495-502,共8页
Journal of the Meteorological Sciences
基金
国家重点基础研究项目"我国南方致洪暴雨监测与预测的理论和方法研究"(2004CB418304)
关键词
暴雨
AREM模式
不稳定
热源
Heavy rain AREM model Instability Heat source
