On the signal of the 11-year sunspot cycle in the stratosphere and its modulation by the quasi-biennial oscillation

In earlier studies we examined the global structure and the size of the signal of the 11-year sunspot cycle (SSC) in the stratosphere and troposphere. For the correlations between the solar cycle and heights and temperatures at different pressure levels we used mainly the whole data set, and only during northern winters, the years were stratified according to the phase of the quasi-biennial oscillation (QBO). This work is expanded here and it is shown that the QBO must be introduced throughout the year, because the solar,signal is very different in the respective phases of the QBO, particularly over the tropics and subtropics. The structure of the solar signal appears to indicate that the mean meridional circulation systems (Hadley and Brewer-Dobson Circulation) are influenced by the SSC, and stronger so during the east phase of the QBO. (C) 2004 Elsevier Ltd. All rights reserved.