摘要
构造了新的诊断量——水汽螺旋度,并对影响水汽螺旋度变化的因子做了分析。利用MM5模式输出资料对2003年7月4日的暴雨过程进行诊断分析,结果表明:水汽螺旋度与暴雨强度和暴雨落区都有较好的相关,螺旋度通量散度和湿螺旋散度对暴雨也有比较明显的指示作用,其中螺旋度通量散度对暴雨落区和强度的指示作用都很好,而湿螺旋散度与暴雨落区对应得稍差。
A new diagnostic quantity--moisture helicity is derived from the moisture equation, and the difinition of helicity, and its influence factors are analyzed in details by the dimensional analysis. The simulated results by the numerical model MM5 of the rainstorm process on 4th to 5th July 2003 are diagnostically analyzed, and results show that the moisture helicity is well correlated. Both the helicity flux divergence and the humid helical divergence have indication for heavy rain, and the former has better indicating effect for both the location and intensity of heavy rainfall, while the latter is only better correclated with the intensity of heavy rainfall.
出处
《南京气象学院学报》
CSCD
北大核心
2007年第1期101-106,共6页
Journal of Nanjing Institute of Meteorology
基金
国家自然科学基金资助项目(404050094007500940205008)
江苏省气象局科技开发项目(200406)
江苏省气象灾害重点实验室资助项目(KLME050201)
国家重点基础研究发展计划项目(2004CB418301)
江苏省自然科学基金资助项目(BK2005141)
关键词
水汽螺旋度
螺旋度通量散度
湿螺旋散度
moisture helicity
helicity flux divergence
humid helicity divergence
