论文部分内容阅读
利用美国卫星TIMED在2002～2006年期间取得的温度数据(L2Aver1.07 SABER/TIMED数据)提取了中间层和低热层(MLT)大气热力潮汐信号,并且利用Hough模分解(HMD)方法考察了DE3潮汐的全球结构.HMD分析结果显示DE3潮汐主要受前两个Hough模的影响,而包括衰减模在内的其他Hough模的影响是可以忽略的.根据HMD分析结果,给出了MLT区域中DE3潮汐活动的中心高度,指出其活动的中心主要受第一传播Hough模,(-3,3)模的控制,出现在110km高度,表现出稳定的单峰年变化(出现在北半球夏季).还发现(-3,3)模表现出以2a为周期的年际变化,它同时清楚地反映在110km高度附近DE3潮汐振幅活动中.在分析时段内,与(-3,3)模2a变化位相一致,DE3潮汐在2002和2004年分别出现显著增强的活动,其中心振幅达到12K以上.分析结果还指出,在100km以下高度,第二传播Hough模,(-3,4)模,也起着重要的影响,使得这里的DE3潮汐活动表现出关于赤道反对称的结构;另外,(-3,4)模表现出双峰年变化的特征,并且在中间层下部区域起着显著的控制作用;与此对应,中间层下部的DE3潮汐活动中心出现在冬末春初和秋末冬初两个季节中,并且交替地出现在赤道以南和赤道以北的热带地区.
The thermodynamic tidal signals of the middle layer and the low-temperature layer (MLT) were extracted by using the temperature data acquired by the US satellite TIMED from 2002 to 2006 (L2Aver1.07 SABER / TIMED data), and the Hough model decomposition (HMD) The global structure of the tide.HMD analysis shows that the tide of DE3 is mainly affected by the first two Hough modules and the influence of other Hough modules including the attenuation module is negligible.According to the results of HMD analysis, The central height of the tidal activity indicates that the center of its activity is dominated by the first propagating Hough modules, (-3,3) modes and appears at a height of 110 km, showing a steady annual monsoon change (appearing in the northern hemisphere summer) It is found that the (-3,3) mode shows an interannual variation with a period of 2a, which is also clearly reflected in the activity of DE3 tidal amplitude near the height of 110 km. During the analysis period, the (-3,3) , The t3 of the DE3 shows significant enhancement activity in 2002 and 2004, respectively, and its center amplitude reaches more than 12 K. The analysis also shows that the second propagating Hough mode (-3,4) mode also plays The important influence that makes the DE3 tidal activity show up here (-3,4) modes exhibit the feature of bimodal variation and play a significant role in controlling the lower part of the middle layer. Correspondingly, the DE3 tidal activity center in the lower part of the middle layer Appeared in late winter and early autumn and early winter early seasons, and alternately appear in the tropics south of the equator and north of the equator.