A Modeling Study on the Atmospheric Response to Winter Arctic Sea Ice Anomalies

摘要

In this study, the NASA GISS ModelE atmospheric circulation modelwas employed to investigate winter atmospheric response to specifiedsea ice anomalies. Two sensitivity experiments were conducted, oneused 10-yr linear trend field of winter sea ice in the high latitude northfrom 40 N to 90 N (Atrend) as the boundary forcing, and the other oneused 10-yr linear trend field of winter sea ice in the north Pacific sector(Ptrend, 60-80 N,30 W-45 E). Our simulation results show that thewinter sea ice anomalies lead to strong response in wintertimeatmospheric circulation and the influence is mainly in the mid- andhigh latitude of northern hemisphere. Atrend excites atmosphericresponse resembling AO/NAO or Northern Hemisphere annular mode,along with strengthened westerly winds, which are unfavorable for thelongitudinal heat exchange in high latitude. Ptrend leads to a patternthat is quite different from AO/NAO, characterized by weakenedwesterly winds, which are favorable for the longitudinal heat exchangein mid- and high latitude. The changes induced by sea ice anomaliesinfluence the weather and climate in northern hemisphere.