Open AccessObserved Evidence of an Impact of the Antarctic Sea Ice Dipole on the Antarctic Oscillation
Author(s) -
Qigang Wu,
Xiangdong Zhang
Publication year - 2011
Publication title -
journal of climate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.315
H-Index - 287
eISSN - 1520-0442
pISSN - 0894-8755
DOI - 10.1175/2011jcli3965.1
Subject(s) - antarctic oscillation , climatology , predictability , geopotential height , forcing (mathematics) , southern hemisphere , northern hemisphere , oscillation (cell signaling) , geology , atmospheric sciences , sea ice , anomaly (physics) , environmental science , meteorology , physics , precipitation , chemistry , biochemistry , quantum mechanics , condensed matter physics
A lagged maximum covariance analysis (MCA) is applied to investigate the linear covariability between monthly sea ice concentration (SIC) and 500-mb geopotential height (Z500) in the Southern Hemisphere (SH). The dominant signal is the atmospheric forcing of SIC anomalies throughout the year, but statistically significant covariances are also found between austral springtime Z500 and prior SIC anomalies up to four months earlier. The MCA pattern is characterized by an Antarctic dipole (ADP)-like pattern in SIC and a positively polarized Antarctic Oscillation (AAO) in Z500. Such long lead-time covariance suggests the forcing of the AAO by persistent ADP-like SIC anomalies. The leading time of SIC anomalies provides an implication for skillful predictability of springtime atmospheric variability.