Recent studies show that an ENSO component of west Antarctic climate variability is related to a persistent zonal pressure anomaly in the south Pacific, which in turn is related to the zonal wave 1 of the subpolar atmospheric circulation. In order to promote further investigation into its dynamics, a suite of time series are presented that describe the intensity and location of ZW1. These time series are shown to represent the SH zonally asymmetric circulation reasonably well. Analysis of the time series suggests that, consistent with previous research, there was a poleward and eastward shift in ZW1 over the late 20th Century. There was also an increase in amplitude variance over this period. Cross-correlation confirms a link with ENSO, and suggests a link between the subtropical and subpolar ZW1. Results also indicate a significant local interaction between south Pacific sea surface temperature and the intensity and location of ZW1.