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The intensity of the winter Siberian High has significantly negative correlations with Arctic sea ice concentration anomalies from the previous autumn to winter seasons in the Eastern Arctic Ocean and Siberian marginal seas. Our results indicate that autumn-winter Arctic sea ice concentration and concurrent sea surface temperature anomalies are responsible for the winter Siberian High and surface air temperature anomalies over the mid-high latitudes of Eurasia and East Asia. Numerical experiments also support this conclusion, and consistently show that the low sea ice concentration causes negative surface air temperature anomalies over the mid-high latitudes of Eurasia. A mechanism is proposed to explain the association between autumn-winter sea ice concentration and winter Siberian High. Our results also show that September sea ice concentration provides a potential precursor for winter Siberian High that cannot be predicted using only tropical sea surface temperatures. In the last two decades (1990–2009), a strengthening trend of winter Siberian High along with a decline trend in surface air temperature in the mid-high latitudes of the Asian Continent have favored the recent frequent cold winters over East Asia. The reason for these short-term trends in winter Siberian High and surface air temperature are discussed.
The intensity of the winter Siberian High has significantly negative correlations with Arctic sea ice concentration anomalies from the previous autumn to winter seasons in the Eastern Arctic Ocean and Siberian marginal seas. Our results indicate that autumn-winter Arctic sea ice concentration and concurrent sea surface temperature anomalies are responsible for the winter Siberian High and surface air temperature anomalies over the mid-high latitudes of Eurasia and East Asia. Numerical experiments also support this conclusion, and consistently show that the low sea ice concentration causes negative surface air temperature anomalies over the mid -high latitudes of Eurasia. A mechanism is proposed to explain the association between autumn-winter sea ice concentration and winter Siberian High. Our results also show that September sea ice concentration provides a potential precursor for winter Siberian High that can not be predicted using only tropical sea surface temperatures. In the last tw o decades (1990-2009), a strengthening trend of winter Siberian High along with a decline trend in surface air temperature in the mid-high latitudes of the Asian Continent have favored the recent frequent cold winters over East Asia. The reason for these short -term trends in winter Siberian High and surface air temperature are discussed.