摘要
研究表明, 正压涡度拟能的增强和减弱是乌拉尔山上空阻塞过程的重要特征, 正压涡度拟能增强的主要机制是斜压涡度拟能向正压涡度拟能的转换, 而斜压涡度拟能的来源则是阻塞区外斜压涡度拟能向阻塞区的净输送和阻塞区内斜压涡度拟能的净生成。正压涡度拟能减弱的主要机制是耗散机制和β效应。因此, 阻塞过程是正、斜压涡度拟能相互作用的结果。纬向斜压风对斜压涡度的输送在阻塞的维持和崩溃中具有重要的作用, 经向斜压风对斜压涡度的输送在阻塞环流的建立中具有重要的作用, 经向正压风对正压涡度拟能的净输送和斜压风对涡度拟能的净输送也具有重要贡献。
The strengthening and weakening of the barotropic enstrophy are the important characteristics of the blocking process over Ural mountains. The main mechanicm of strengthening barotropic enstrophy is the transformation from baroclinic to barotropic enstrophys. The baroclinic enstrophy comes from the net transport from outside to inside of the blocking area and the net growth of the baroclinic enstrophy. The weakening mechanisms of the barotropic enstrophy are the drag machanism and effect. Therefore, the blocking process is the result of barotropic and baroclinic enstrophy interaction. The transportation of baroclinic vorticity under influence of zonal baroclinic wind has great effect on the maintaining and declining of blocking.And the transportation of baroclinic vorticity with the meridional baroclinic wind is vital in the shaping of blocking.The transportation of barotropic enstrophy under influence of meridional barotropic wind and the transportation of mixing enstrophy under influence of baroclinic wind also have key contribution.
出处
《高原气象》
CSCD
北大核心
2005年第2期178-186,共9页
Plateau Meteorology
基金
科技部基础研究重大项目前期研究专项"四大气象科学试验综合分析研究暨‘东亚季风科学试验预研究’"资助
关键词
正、斜压涡度拟能
转换机制
净通量机制
乌拉尔阻塞环流
Barotropic and baroclinic enstrophys
Transformation mechanism
Net flux mechanism
Ural blocking circulation
