Sunspots, the QBO and the stratosphere in the North Polar Region - 20 years later

We have shown in earlier studies the size of the changes in the lower stratosphere which can be attributed to the 11-year sunspot cycle (SSC). We showed further that in order to detect the solar signal it is necessary to group the data according to the phase of the Quasi-Biennial Oscillation (QBO). Although this is valid throughout the year it was always obvious that the effect of the SSC and the QBO on the stratosphere was largest during the northern winters (January/February). Here we extend our first study (LABITZKE, 1987) by using additional data. Instead of 30 years of data, we now have 65 years. Results for the entire data set fully confirm the early findings and suggest a significant effect of the SSC on the strength of the stratospheric polar vortex and the mean meridional circulation.