Fig. 1.

Sea-level pressure wintertime atmospheric circulation patterns with significant occurrence trends and associated surface anomalies: Composite anomalies of DJF sea-level pressure (A and B), 10-m horizontal wind speed (C and D), 2-m temperatures (E and F), and precipitation rates (G and H) for days with increasing (A, C, E, and G) or decreasing (B, D, F, and H) occurrence trends. In the composites (A–H), contours indicate regions with changes significant at the one-sided 5% level, computed with a bootstrap sample size of 500. Spatial averages of seasonal temperature anomalies (black) and precipitation rates (blue) during the days with increasing (I) or decreasing (J) occurrence trends and count of days displaying the corresponding occurrence trend (orange stems) during DJF. Solid lines represent linear trends of the spatial averages with the 95% confidence intervals of the two linear fits in each panel shown in the legends. The averages in (I) and (J) are computed on all European land points (SI Appendix Fig. S3).