Fig. 6: Constraining Pacific SST trends improves poleward jet shift trends in coupled models.
From: Robust impact of tropical Pacific SST trends on global and regional circulation in boreal winter
a DJF 500h-Pa zonal-mean zonal wind trends (1981/82-2018/19) in reanalyses. b, c Distribution of DJF jet shift trends (1981/82-2018/19) in the (b) SH and (c) NH, respectively, using the zonal indices of Woollings et al.18. Positive trends correspond to poleward jet shifts. Boxes indicate the interquartile range and median trend, while whiskers represent 10–90% of the trend distribution. Thicker lines indicate where the ensemble-mean trends in the Pacific and non-Pacific ensembles are significantly different at the 5% significance level, using a two-tailed Student’s t-test. Reanalysis trends are shown by the black horizontal lines. Light and dark gray shading in (a) indicates the equatorward and poleward latitude bands used to calculate the zonal wind indices.
