Observed correlations between winter‐mean tropospheric and stratospheric circulation anomalies

It is shown that interannual variability of the northern winter stratospheric flow in 1964‐1993 was closely linked to large‐scale circulation anomalies in the middle troposphere. Of the known tropospheric teleconnection patterns, the one having the strongest relation to the DJF zonal‐mean stratospheric flow was the North Atlantic Oscillation (NAO). Singular value decomposition between the 500 and 50‐hPa geopotential heights produced a 500‐hPa structure containing elements of the NAO pattern, but including an anomaly in eastern Siberia. During this time period, the correlation of NAO‐related modes to the polar lower stratosphere exceeded that of the equatorial quasi‐biennial oscillation.