Abstract:

Based on daily Antarctic sea ice concentration data acquired by AMSR-E during 2002—2011, this study calculated the extent and area of sea ice and analyzed the spatiotemporal characteristics of its variability over different timescales. The results revealed increases of 3.64% decade^–1 in sea ice extent and 3.8% decade^–1 in sea ice area. The derived 10-year trend of sea ice for the entire Antarctic sea ice area was significantly positive, and the year of 2008 experienced the maximum sea ice area. Regionally, increases were found in the Ross Sea, Weddell Sea, and Western Pacific sectors, and small decreases were detected in the Indian Ocean and the Bellingshausen Sea and Amundsen Sea sectors. Seasonally, both sea ice extent and sea ice area in the Antarctic are at a minimum in summer and a maximum in winter. In the same season, the various regions have different ranges of variation in sea ice area. First-year ice is mainly distributed around the Antarctic mainland, except for the Weddell Sea sector, and the trend of sea ice area is generally positive (0.1×106 km²·a^–1), which is in marked contrast to the decrease in the multiyear ice area of –0.05×106 km²·a^–1; most multiyear ice is distributed within the Weddell Sea sector. The change of sea ice extent is correlated negatively with temperature.

Key words: Antarctic, sea ice extent, sea ice area, AMSR-E, temperature, spatiotemporal variation