2002—2011年南极海冰变化的遥感分析

ANALYSIS ON SPATIOTEMPORAL VARIATIONS OF ANTARCTIC SEA ICE DURING 2002—2011

基于2002—2011年南极地区AMSR-E逐日海冰密集度数据,计算相应时间段内的海冰外缘线和海冰面积,分析了南极地区这10年来各时间尺度上的海冰变化,揭示了海冰变化的时空特征。结果表明:2002—2011年南极海冰外缘线、海冰面积分别增加了3.64%、3.8%,总体上呈现增加的趋势,其中2008年海冰面积最大。罗斯海、西太平洋和威德尔海的海冰面积呈现增加趋势,而印度洋和别林斯高晋海/阿蒙森海的海冰面积则趋于减小。南极海冰面积一般夏季最小、冬季最大,相同季节海冰面积变化波动较小,不同海区只是变化范围不同。南极一年冰增长速度较低,平均每年增加约0.1×10~6 km^2,且大范围地分布在南极大陆(除威德尔海外)周围。多年冰平均每年减少0.05×10~6 km^2,且多处于威德尔海。海冰面积变化与气温有负相关关系。

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 ×10^6 km^2·a^-1）, which is in marked contrast to the decrease in the multiyear ice area of-0.05×10^6 km^2·a^-1; most multiyear ice is distributed within the Weddell Sea sector. The change of sea ice extent is correlated negatively with temperature.