摘要
利用1965—1986年30hPa 逐日高度、温度资料和月平均臭氧资料,对环流的春季转变过程进行了诊断研究。结果表明:50°N 以北极冠地区高度场涡动方差 E 指数小于4×10~4(dagpm)~2的初日可以作为30hPa 自然天气季节进入春季的近似度量;冬末至早春环流在压、温和经、纬向风场方面均有显著变化;定常和瞬变涡旋动量、热量通量和通量辐散(合)的时-空变化特征明显;春季转变早、迟两类情况下极区平流层热源——臭氧在经向、纬向和垂直分布方面呈现异常。
Based on the northern 30 hPa daily altitude and temperature data for 1965—1986 andmonthly mean ozone observations for 1958—1976,studies are conducted on the natural transi-tional process of the circulation from winter to spring by means of dynamic approach and statisti-cal diagnostic analysis.Results are obtained as follows:(1)the first day on which the E index ofeddy variance of the height field in the polar-cap area north of 50°N is smaller than 4×10~4(dagpm)~2 can be taken as an approximate measure of the beginning of spring for the natural sea-son;(2)the circulation in the period from late winter to early spring experiences significantchanges in the pressure,temperature,and zonal-meridional wind fields;(3)stationary and tran-scient vortex momentum,heat flux and flux convergence(divergence)undergo remarkable tem-poral-spatial variations;(4) in both the early and late transitions into spring,the heatsource——ozone in the polar stratosphere shows zonal,meridional and vertical anomalies.
出处
《应用气象学报》
CSCD
北大核心
1992年第3期306-313,共8页
Journal of Applied Meteorological Science
