摘要
通过对中纬度地区大、中尺度突发性灾害天气的动力学分析表明：突发性灾害天气具有迅速激发和相对稳定演变的特征；激发过程是在湿位涡趋向于零的条件下，由于影响湿位涡的各项因子动态不平衡而引起的湿位涡不守恒过程，在中纬度地区表现为地转偏差的激发过程。突发性灾害天气开始发生的时刻往往与影响湿位涡各作用项的某一项发生转折性变化的时刻相对应，而初始产生地是湿位涡趋向于零的地区。
Through the dynamical analysis on the sudden calamitous weather,it shows that:the sudden calamitous weather has the feature of quickly excitative rapid process and relatively stable development slow process;the excitative process of the sudden calamitous weather is the non conservative process of wet potential vorticity resulted from the dynamic non equilibrium of various factors affecting potential vorticity in the condition of wet potential vorticity tending to zero, and it is the excitation process of the geostrophic departure in middle latitudes;the happening time of the sudden calamitous weather is often corresponding to the time of the turning change of one of the factors affecting potential vorticity, while the happening area is the area where the wet potential vorticity tends to zero.
出处
《南京气象学院学报》
CSCD
1999年第4期711-715,共5页
Journal of Nanjing Institute of Meteorology
基金
安徽省减灾科学基金
关键词
突发性灾害天气
湿位涡不守衡
动力学分析
sudden calamitous weather
non conservative process of wet potential vorticity
dynamical analysis
