Fig. 2: The influence of the Arctic Oscillation on Arctic weather variability.
a shows a set of nonlinear time series generated based on Eqs. (1–4). Autocorrelation functions and weighted autocorrelation function WACF values are shown in (b), while power spectrum density and weighted power spectrum WPS values are shown in (c). Correlations between the annual mean of the Arctic Oscillation (AO) index and the WACF for Arctic sea ice are depicted in (d) and for WPS in (e). Nodes with correlations significant at the 95% confidence level (Student’s t-test) are marked with “x". f compares the normalized power spectral density (PSD) of sea ice for nodes marked with “x" in (e) during Jan. 1989 (positive AO phase, blue solid lines) and Jan. 2010 (negative AO phase, red dashed lines). g The monthly and annual AO index (pink solid and dashed lines, respectively) are plotted against the monthly and annual WACF index (dark blue solid and dashed lines, respectively) averaged over the nodes marked with “x" in (d). h The relationship between the AO and WACF indices is further illustrated through scatter plots of annual indices. The correlation coefficient (r) between these two indices is 0.63, with a p-value of 5.5 × 10−6. Source data are provided as a Source Data file.
