平流层冬季增温及大气中的行星波

Stratospheric Winter Warmings and Planetary Waves in the Atmosphere

本文利用NIMBUS-7 SAMS资料分析了东经100度子午线上的两个站点(67.5°N和42.5°N)在10mb和0.0827mb高度上从1978年底至1982年间的大气温度,获得几年的平流层冬季增温结果.在1978/1979年和1981年初的冬季,高纬站点几天内出现的平流层增温最大幅度可达65K.对平流层增温的谱分析结果指出,在高纬冬季平流层有很强的16天、32夭、21天周期的行星波。中纬冬季平流层增温幅度较小,约为20K.中纬的中间层高度上整年存在有5天、8天和16天的行星波。分析研究、南、北半球不同纬度的温度随经度的分布,得出高纬冬季平流层、中间层大气温度随经度有明显的变化。波数1和波数2的波有大的幅度(主要是波数1),从高纬到低纬,波幅逐渐减小;在冬季的平流层和中间层大气中,波数1和波数2的行星波在短期内可强烈增强,引起平流层冬季增温。

In this paper, the atmosphere temperature at (67.5°N, 100°E) and (42.5°N, 100°E) at 10 mb and 0.0827mb levels from the end of 1978 to 1982 is analysed by using NIMBUS-7 SAMS GRID-T data. The main features of the stratospheric winter warmings are obtained. It is shown that the temperature increase reached 65K in a few days at (67.5°N, 100°E) at the 10 mb level in the winter 1978/1979 and the winter of the beginning of 1981. The results of the spectrum analysis of the stratospheric sudden warmings indicate that there exist strong planetary waves with periods of '16-day', 32-day' and '21-day' at high latitudes in winter stratosphere. There are 20K temperature increase at middle latitude during stratospheric winter warming. There exist planetary waves with periods of 16, 8 and 5 days in the mesosphere at middle latitude all the year. The results of the temperature variation with the longitude at different latitudes for both hemispheres are given. It is revealed that the middle atmosphere temperature often varies obviously with the longitude at high latitude in winter, the amplitudes of wave 1 and 2 are large, and they reduce gradually from high latitude to low latitude. It causes the stratospheric winter warmings with amplitudes of wave 1 and 2 increasing sharply in a few days in winter middle atmosphere.