基于SABER/TIMED温度数据的全球平流层顶与重力波活动的气候学特征的观测研究

Climatology of Global Stratopause and Gravity Wave Activity Revealed by SABER/TIMED Temperature Observations

利用2002年1月25日—2012年12月31日的SABER/TIMED温度数据,统计分析了平流层顶的变化特征及其与平流层顶区域重力波和背景纬向风场的相关性。在南、北半球0°~30°的低纬区域,平流层顶高度呈现冬夏季较高的半年变化,此时重力波活动较强,而平流层顶温度呈现春秋较大的半年变化;在南北半球40°~50°的中纬区域,平流层顶的高度、温度与重力波活动都呈现年变化,其中平流层顶高度与重力波活动的极大值出现在冬季,而平流层顶温度的极大值出现在夏季。相关性分析显示,平流层顶高度与重力波活动强度主要呈正相关,而平流层顶温度与重力波活动强度主要呈反相关;低纬的背景纬向风在春分秋分较大,与平流层顶温度呈正相关,而中纬的背景纬向风则在冬季较强,与平流层顶温度呈反相关;平流层顶的高度、温度与重力波活动强度、纬向风间相关系数都具有南北半球不对称性。并且,平流层顶高度和温度的峰值都随纬度增大,同时,重力波活动和背景风场也随纬度增强,表明平流层顶与重力波活动和背景风场间的相互影响。

Using 11-year SABER/TIMED temperature observation from January 25,2002,to December 31,2012,we statistically study the global stratopause and the correlations of the stratopause with the gravity waves(GWs)and background zonal wind in the stratopause region.At low latitudes of 0°-30°in the northern and southern hemispheres,the stratopause height and GW activity show semi-annual variation with peaks in summer and winter.In contrast,the stratopause temperature shows semi-annual variation with peaks in spring and autumn.At mid-latitudes of 40°-50°in the two hemispheres,the annual oscillation dominates the variations in the stratopause height,temperature and GW activity,and the peaks of stratopause height and GW activity appear in winter.Still the maximum of the stratopause temperature occurs in summer.Statistical analysis indicates that the stratopaue height positively correlates with GW activity,while the stratopaue temperature is inversely associated with GW activity.The background zonal wind at low latitudes is significant in spring and autumn equinoxes.It shows a positive correlation with the stratopause temperature,but at middle latitudes,it is vital in winter and has an inverse correlation with the stratopause temperature.The correlation coefficients among the stratopause height,temperature,gravity wave(GW)activity,and the background zonal wind exhibit asymmetry between the northern and southern hemispheres.Meanwhile,the peak values of the stratopause height and temperature increase with latitude,while similarly,GW activity and the background zonal wind also increase with latitude,indicating the interaction among the stratopause,GW activity and background wind field.