For the years from 2001 to 2013, the atmospheric densities and temperatures in the transition flow region of east and central China are simulated by the US Naval Research Laboratory Mass Spectrometer Incoherent Scatter (NRLMSISE-00) model, with the space environment indices including 10.7cm solar flux and the geomagnetic activity index Ap) as the external forcing factors. The simulation results are analyzed. Variations of monthly averaged densities and temperatures from different reference sites agree well with each other. The semiannual variation of the atmospheric density above 90 km is found from spectral analysis. The amplitudes of the semiannual variation increase with the increase of the latitude between 90km and 110km. From the spectral results, the maximum and minimum densities of the first cycle of the semiannual variation are found, respectively, in March and June at 100 km, which is significantly earlier than the previous results of the middle and upper thermospheres.%利用美国海军研究实验室在 MSIS 系列模型基础上发展的大气模型 NRLMSISE-00,模拟研究了 2001年—2013年中国上空过渡流区80~140km高度的大气状态.对于中国东部和中部过渡流区,基于模拟数据得到的月平均结果显示大气密度和温度呈现一致的变化趋势,还表现出与太阳活动的显著关联.谱分析的结果显示,在90 km高度以上大气密度呈现半年周期变化,在90~110 km高度范围这种半年变化的幅度随纬度增大.在100 km高度,上半年出现的半年周期过程中密度的最大、最小值分别出现在3月和6月,明显超前中、高热层的半年周期过程.
展开▼
