Abstract: The “warm Arctic-cold Eurasia” (WACE) pattern is one of the key modes of winter Arctic-Eurasia climate variability, exhibiting multi-timescale variation characteristics. The weakening of the “Arctic warming-Eurasia cooling” trend since 2012 has sparked intense discussion of whether the Arctic-Eurasia climate linkage has disappeared or weakened. Diagnostic analyses based on multi-source data indicate that the timescale of the close connection between the Arctic and Eurasian climates shifts from winter means to subseasonal variations, presenting an increasing and strengthening phase reversal of the WACE between early and late winter. The WACE pattern can lead to a weakened large-scale meridional temperature gradient, resulting in persistent and large-amplitude atmospheric circulation anomalies, which in turn trigger extreme cold waves. More importantly, the WACE reversal can drive extreme cold‒warm transitions in the Mongolian region and eastern China. Because Mongolia is a major dust source for China, rapid wintertime phase-reversals lead to loose, bare ground surfaces, providing ample material and conducive conditions for severe sandstorms in North China. The physical variations in early and late winter can be more clearly understood by considering a WACE on the subseasonal scale. The occurrence of WACE in late winter also significantly impacts haze pollution in North China and is a key predictor of Arctic wildfires. Future research on the WACE pattern should focus on its trends and associated uncertainties, clarify the mechanisms underlying phase reversals, and enhance the efficacy of climate models for simulating and predicting these patterns, thereby improving the accuracy of predicting winter-spring extreme climates at mid-to-low latitudes.