资源环境科技发展态势分析平台

This study investigates the intraseasonal variations of the Arctic sea ice concentration (SIC) based on daily data band-passed for 20-80 days. Results show that the areas with strong intraseasonal signal of SIC move northward and then southward before and after the Arctic summer (i.e., from August to October), respectively, and the signal reaches its maximum intensity in summer. Power spectrum analyses indicate that the SIC over the region bounded by 0-180 degrees E and 70-80 degrees N (60-180 degrees W and 70-80 degrees N) in summer exhibits remarkable intraseasonal variation with a dominant period of 40-60 days (two typical periods of 40-60 and 70-80 days). These two kinds of oscillations move eastward along the Arctic marginal sea. In addition, the intensity of SIC intraseasonal oscillation has an apparent interdecadal change that is closely related to the decrease of Arctic sea ice extent.