摘要
因为在联合不同大气的区域的重力波浪(GW ) 的重要性,进一步的研究是必要的在非等温的气氛调查 GW 繁殖的特征。用一个非线性的数字模型,我们在不同非等温的气氛与各种各样的波长模仿小振幅 GW 的繁殖。我们的结果证明 GW 垂直波长在 stratopause 和中圈顶区域上面经历锋利的变化。明确地为有 5 km 的起始的垂直波长的 GW,在 50
Because of the importance of gravity waves (GWs) in coupling different atmospheric regions, further studies are necessary to investigate the characteristics of GW propagation in a non-isothermal atmosphere. Using a nonlinear numerical model, we simulate the propagation of small amplitude GWs with various wavelengths in different non-isothermal atmospheres. Our re- sults show that the GW vertical wavelength undergoes sharp changes above the stratopause and mesopause region. Specifically for a GW with an initial vertical wavelength of 5 km, the seasonal background temperature structure difference at 50° latitude can cause the vertical wavelength to vary by -2 krn in the mesosphere and by as large as -4.5 km in the lower thermosphere. In addition, the GW paths exhibit great divergence in the height range of -65-110 kin. Our results also show that the variations of GW path, vertical wavelength and horizontal phase velocity are not synchronized in a non-isothermal atmosphere as in an isothermal atmosphere. Despite the fact that all GWs change their characteristics as they propagate upward in a non-isothermal atmosphere, the variations relative to the initial parameters at a reference height are similar for different initial vertical wavelengths. Our results indicate that the changing characteristics of a gravity wave in a non-isothermal atmosphere need to be considered when investigating the relationship of GWs at two different heights.
基金
supported by the National Natural Science Foundation of China (Grant Nos. 40921063, 41004063, 41074109, 40890165, and 41174127)
the National Important Basic Research Project (Grant No. 2011CB811405)
the China Postdoctoral Science Foundation (Grant No. 20100470506)
supported in part by the Specialized Research Fund
the Open Research Program of the State Key Laboratory of Space Weather
the National Science Foundation of Unites States grant-ATM-0633418 to Miami University