摘要
用位势涡度方程对1980年1月26-30日东亚寒潮高压的演变做了诊断研究,表明高压中心地区低层是低值位涡区,位涡值随高压增强(减弱)而变小(变大);随着高压的发展加强,位涡最小值由对流层中层降到近地面层,随着高压的减弱,最小值中心又上升;对流层高层的位涡值随着地面高压的增强而加大,反映高空冷槽、地面高压同时在发展。位涡收支方程各项对高压发展、减弱有着不同的作用。作用最大的是地转风水平平流项和地转偏差风的散度项,其次是地转偏差风的平流项和辐射项,扭转项和热成风偏差项均甚小,可忽略不计。
A diagnostic study is made of a cold wave-related anticyclone in East Asia,for 26-30 January 1980,by using the potential vorticity equations. The results show that atthe initiation stage in the vicinity of anticyclonic centre there is a low potential vorticityarea where it decreases(increases)with the intensification(descension)of the high;when the high developing it descends from the middle troposphere to the nearer groundlayer,when the high decaying it ascends from the lower troposphere;while the poten-tial vorticity in upper troposphere increases with the intensification of surface high. The various terms in the potential vorticity equations have made very different con-tributions to the evolution of the anticyclone. The first contribution comes from thegeostrophic advection of potential vorticity and the divergence term of geostrophic devia-tion wind.The secondary are the advection of geostrophic deviation wind and radiationheating(cooling).The twisting term and thermal wind term could be ignored.
出处
《应用气象学报》
CSCD
北大核心
1994年第1期49-56,共8页
Journal of Applied Meteorological Science
关键词
寒潮
高压
位涡
涡度
东亚
Potential vorticity
Cold wave high.