Interannual variability in the Southern Hemisphere troposphere.

A pronounced quasi-biennial oscillation (QBO) with a systematic poleward progression of the anomalies is present throughout the troposphere in the zonal-mean anomaly fields of the height and wind but is absent in the thickness fields. The QBO is clearest at the bottom of the atmosphere and appears to have a barotropic structure.-from Authors quasi biennial oscillation zonal mean anomaly fields barotropic structure