Abstract: Changes in sea ice extent have a significant impact on climate change, ecosystems, and human activities, and the change in polar sea ice extent has created major concern in recent years. In this paper, sea ice extent in the Ross Sea and Prydz Bay in Antarctica were compared using time-series analysis. There were distinct differences in the patterns of seasonal variation in sea ice extent between the Ross Sea and Prydz Bay. The Ross Sea showed rapid decrease–rapid growth, while Prydz Bay showed rapid decrease–slow growth. However, annual variations in sea ice extent in both regions are increasing. The annual trend in the Ross Sea was (1.39 ± 1.12)×10⁴ km² a^-1 while in Prydz Bay the trend was (0.61 ± 0.26)×10⁴ km² a^-1 . The annual growth of winter sea ice extent was higher than that of summer sea ice extent in both areas, and the annual trend in the Ross Sea region showed negative growth in summer sea ice extent.

Key words: sea ice extent, Ross Sea, Prydz Bay