DOWNWARD PROPAGATION OF UPPER STRATOSPHERIC MEAN ZONAL WIND PERTURBATION TO THE TROPOSPHERE

An investigation is conducted to determine the influence of changes in the upper stratospheric mean zonal wind on the circulation of the lower atmosphere. In addition to observed data, results of numerical experiments with a general circulation model are used, in which the solar ultraviolet heating rate is varied to force changes in the mean zonal wind in the upper stratosphere. It is found that when the upper stratospheric mid‐latitude westerlies are strong during December, lower stratospheric polar night jet is persistent and the westerlies in the polar region of the troposphere become stronger in the following February. These results are common to both the observations and the numerical experiments. Copyright 1990 by the American Geophysical Union.