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*The temperature anomalies are December–January means, spatially averaged over the 75°–90°S, 180°–90°W sector of West Antarctica, and calculated with respect to the 15-year mean of the control simulation. The warm and cold columns correspond to positive and negative temperature anomalies, respectively.
†The SAM index represents the November–January average. The positive (+SAM), neutral, and negative (−SAM) phases are defined based on the ±0.5 standard deviation of the SAM index.
‡Expected counts (which assume independence between the two variables) are given in parentheses. The chi-square statistic is 14.67. The P value is 0.00065.