Relative roles of the MJO and stratospheric variability in North Atlantic and European winter climate

摘要: European and eastern United States wintertime weather is strongly influenced by large-scale modes of variability in the Northern Hemisphere such as Arctic Oscillation (AO) North Atlantic (NAO). The negative phase NAO has been linked to both Madden-Julian (MJO) with convection West Pacific (phases 6 7) stratospheric sudden warmings (SSW), but relative role each phenomenon not clear, two phenomena are themselves linked, more than half SSW events were preceded phases 7 MJO. Here we disentangle roles MJO 6/7 for surface during boreal winter. We show that leads significantly different anomalies if it 6/7. Furthermore, a long-lived AO pattern only modulates stratosphere first. Hence, proper attribution their respective influence on needs take into consideration linkages between these phenomena. Finally, lead can be differentiated from those which do characteristics within tropics: enhanced propagates South China Sea, rarely occurs winter, SSWs.