![]() For instance, Japan suffered an extreme snowstorm in December 2005, and China suffered persistent cold and freezing rain events in January–February 2008 ( WMO Regional Climate Centres 2012) and extreme cold conditions and heavy snowfall attacked North America in two consecutive winters (2013//15), during which the Great Lakes were almost completely frozen for the first time in the previous 35 years and Boston experienced record-breaking snowfall reaching 2.7 m ( Van Oldenborgh et al., 2015).Ī range of mechanisms have been proposed for the frequent occurrence of extreme cold and snowy climates during the past 2 decades. In recent decades, the midlatitudes of the Northern Hemisphere have experienced more frequent cold winters and extreme weather events ( Wu et al., 2011 Cohen et al., 2014 Li et al., 2015 Cohen et al., 2020 Wang et al., 2021). These results have important implications for future seasonal and interdecadal forecasts in the context of ongoing sea-ice decline. Such midlatitude anomaly is dynamically linked to winter sea-ice loss, mainly through tropospheric rather than stratospheric pathways. The anomalous dipole cyclone and anticyclone over the Bering Sea transport more Pacific and Arctic water vapor to North America, and the anomalous cyclone over the Barents Sea results in abundant precipitation in Siberia. In contrast, Ber sea-ice loss is associated with a circumglobal wave train downstream of the Bering Sea, leading to extensive warming over Eurasia. The former results in excessive precipitation over northwestern and southeastern North America, whilst the latter leads to less precipitation and mild winter over Siberia. For wintertime sea-ice loss in the Pan-Arctic and BKL, a weak positive NAO phase, with a dipole pressure pattern over Greenland–northeastern North America and North Atlantic, and a shrunken Siberian high over Eurasia are observed over mid–high-latitudes. Meanwhile, an anomalous cyclone over Europe favors excessive precipitation over southern Europe. Specifically, autumn sea-ice loss appears to cause a weakened stratospheric polar vortex that propagates to the troposphere in the ensuing months, leading to lower surface air temperature and a deficit in precipitation over Siberia and northeastern North America. ![]() Results suggest that interdecadal reduction of autumn sea-ice, irrespective of geographical location, is dynamically associated with the negative phase of the North Atlantic Oscillation (NAO) in the subsequent winter via stratospheric pathways. ![]() Four critical sea-ice subregions are analyzed in this study-namely, the Pan-Arctic, Barents–Kara–Laptev Seas (BKL), East Siberia–Chukchi–Beaufort Seas (EsCB), and Bering Sea (Ber). Here, we use reanalysis data to investigate the possible linkage between mid–high-latitude atmospheric circulation and Arctic sea-ice loss in different geographical locations and seasons and associated impacts on wintertime climate on interdecadal timescales. 3Innovation Center of Ocean and Atmosphere System, Zhuhai Fudan Innovation Research Institute, Zhuhai, Chinaĭuring the past few decades, Arctic sea-ice has declined rapidly in both autumn and winter, which is likely to link extreme weather and climate events across the Northern Hemisphere midlatitudes.2Shanghai Qi Zhi Institute, Shanghai, China. ![]() 1Department of Atmospheric and Oceanic Sciences, Institute of Atmospheric Sciences, Fudan University, Shanghai, China.Xulong He 1 Ruonan Zhang 1,2,3* Shuoyi Ding 1 Zhiyan Zuo 1
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