  Gravity waves are primarily generated in the lower atmosphere, and can reach
thermospheric heights in the course of their propagation. This paper reviews
the recent progress in understanding the role of gravity waves in vertical
coupling during sudden stratospheric warmings. Modeling of gravity wave effects
is briefly reviewed, and the recent developments in the field are presented.
Then, the impact of these waves on the general circulation of the upper
atmosphere is outlined. Finally, the role of gravity waves in vertical coupling
between the lower and the upper atmosphere is discussed in the context of
sudden stratospheric warmings.
