环境场特征与暴雨之间的关系浅析

利用2002年6-7月香港天文台业务区域谱模式(ORSM)的物理量预报资料，通过对暴雨发生时的平均高度场、温度场、湿度场、经向及纬向风速场特征的分析，探讨了我国南方形成持续强降水的大尺度环流形势及物理条件.通过对暴雨带附近的热力场和动力场的研究表明：温度场上，在大气中低层，暴雨带处于高温区南侧相对的冷区，且温度梯度较小，而在暴雨区北侧，温度梯度较大；湿度场上，暴雨区落在高湿度带中，并且在大气低层，暴雨带位于南北相对湿度对比带的南侧；而在风速场上，在大气低层，暴雨带附近为东西风及南北风的复合带.

Analysis on the Relationship between Heavy Rainfall and Features of Environmental Fields(Chinese)

Hong Kong Observation Operational Regional Spectral Model(ORSM) forecasting physical values in June and July 2002 were used to explore the large-scale atmosphere circulation situations and physical conditions causing continuously severe rainfall in the south of China by analyzing the features of average geopotential height field,temperature field,humidity field,meridional and zonal wind(velocity) field when heavy rainfall took place.The study of the thermodynamic and dynamical field near the heavy rainfall belt indicates that in temperature field,at the low and middle level of atmosphere,the heavy rainfall belt lies in the comparatively colder zone south of the high temperature zone with lower gradient,while the gradient is higher in the north of the heavy rainfall belt.On the other hand,in humidity field,the heavy rainfall belt is located in the high humidity zone,while at the low level of atmosphere,it is in the south of relative humidity gradient zone.Furthermore,in wind velocity field,at the low level of atmosphere,the heavy rainfall belt existed in the convergence zone of the east and west winds,south and north winds.