1220 / 2019-08-07 11:27:03

Role of atmospheric factors in forcing Arctic Sea ice variability

15、冰冻圈科学 > 专题6：海-冰-气相互作用的物理过程和机制

The spatial structure of the Arctic Sea ice concentration (SIC) variability and the connection to atmospheric as well as radiative forcing during winter and summer for the 1979-2017 period are investigated. The interannual variability with different spatial characteristics of SIC in summer and winter is extracted using the empirical orthogonal function (EOF) analysis. The present study confirms that the atmospheric circulation has a strong influence on the SIC through both dynamic and thermodynamic processes, as the heat flux anomalies in summer are radiatively forced while those in winter contain both radiative and ‘‘circulation-induced’’ components. Thus, atmospheric fluctuations have an explicit and extensive influence to the SIC during both seasons. However, interannual sea ice variability patterns in winter are dominated by changes in large-scale atmospheric circulation while thermal radiation plays a crucial role in summer. Moreover, analysis of a variety of atmospheric variables indicates that the primary mechanism about specific regional SIC patterns in Arctic marginal seas are different with special characteristics.