A lagged maximum covariance analysis (MCA) is also applied to capture the cross-seasonal coupled patterns between the Southern Ocean sea surface temperature (SOSST) and extratropical Z500 anomalies in the SH. Statistically significant results show that the dominant feature of ocean–atmosphere interaction is likely the effect of atmosphere on SOSST anomalies, with a peak occurring when the atmosphere leads the SOSST by 1 month. However, the most eye-capturing phenomenon is that the austral autumn atmospheric signal, characterized by a negatively polarized AAO, is significantly related to the gradual evolution of preceding SOSST anomalies, suggesting that the SOSST anomalies tend to exert an effect on the SH atmospheric circulation. It is also demonstrated that the gradual evolution of changes in SOSST is mainly driven by internal atmospheric variability via surface turbulent heat flux associated with cold or warm advection and that the atmospheric circulationexperiences a change from a typical positive AAO to a negative phase in this process. These findings indicate that such a long lead cross-seasonal covariance could contribute to a successful prediction of AAO-related atmospheric circulation in austral autumn from the perspective of SOSST anomalies, with lead times up to 6–7 months.
Wu, Q.*, and X. Zhang, 2011: Observed evidence of an impact of the Antarctic sea ice dipole on the Antarctic Oscillation. Journal of Climate. 24. 4508-4518.
Hu, C., Q. Wu*, et al. 2016: A linkage observed between austral autumn Antarctic Oscillation and preceding SST anomalies. Journal of Climate, 29, 2109-2122.