Dynamics of zonal mean characteristics of circulation in stratosphere and mesosphere in winter

The model of the middle and upper atmosphere circulation (MUAM) and the data of the ERA-interim archive are used to study the mean zonal variations of wind velocity and temperature in the middle atmosphere. Comparison of model calculations and data of ERA-interim archives showed that the model adequately reproduces the main features of circulation processes in the winter stratosphere. The analysis of variations in the mean zonal characteristics of the atmosphere is show that synchronous variations there are in wind velocity and temperature in the stratosphere and mesosphere in the range of 10-30 days . These synchronous variations occupy long latitudinal zones horizontally (tens degree) and have a significant length vertically (tens km). The sign of the variations change horizontally in the region of jet streams (and does not change at the equator), and the vertical change of sign occurs in areas of the stratopause and the mesopause. The nature of  the variations practically does not depend on the phase of the quasi-biennial cycle in the Equatorial stratosphere. The variations are global scale and are reminiscent of the fluctuations in the meridional circulation cells. The dynamic processes of destruction of the polar vortex during sudden stratospheric warming are coordinated with these synchronous variations.

Acknowledgements. This work was supported by the Russian Science Foundation, project No. 19-77-00009.  The authors gratefully acknowledge the access to the ECMWF ERA-Interim.