南极海冰的时空变化特征

SPATIO-TEMPORAL CHARACTER OF ANTARCTIC SEA ICE VARIATION

依据Hadley中心提供的全球海冰密集度格点资料 ,利用诊断分析方法 ,对近 35年来南极海冰的时空变化特征进行了研究。研究表明 ,在南极地区 ,海冰平均北界和海冰总面积的变化基本一致 ,可以用海冰北界来研究南极海冰的时空变化特征。南极海冰最多和最少期分别出现在 9月和 2月 ;威德尔海和罗斯海地区海冰最多、变化最大 ,南极半岛地区海冰最少 ,变化也小 ;近 35年来环南极地区的海冰有明显的减少趋势。南极海冰变化的时空多样性十分明显 ,存在着 5个变化不同的区域 ,其中有两个区域近 35年来海冰范围扩大 ,面积增加 ,而另三个区域则海冰范围缩小 ,面积减少。不同区域的海冰都存在着较明显的 2— 3年和 5— 7年主振荡周期。南极海冰时空变化特征的研究对进一步认识南极地区海 冰 气相互作用的物理过程 。

Using sea ice concentration dataset covering the period 1968-2002 obtained from the Hadley Center of UK, this paper investigated characters of Antarctic sea ice variations. The finding demonstrated that the change of sea-ice extent is almost consistent with that of sea-ice area in every longitude, so we last choose sea-ice extent to go on this research. The maximum and the minimum of Antarctic sea ice appear in September and February respectively. The maximum and the maximal variation of sea ice appear in Weddell Sea and Ross sea, while the minimum and the minimal variation of sea-ice appear inAntarctic Peninsula. In recent 35 years, as a whole, the sea ice in Antarctica decrease distinctly. There are 5 subdivision regions in total considering their different variation. Thereinto, the sea-ice extent of Weddell Sea and Ross Sea regions extends and area increases, while the sea-ice extent of the other three regions shrinks and area decreases. They are all of obvious 2-3 years and 5-7 years significant oscillation periods. It is of significance for further understanding the sea-ice-air interaction in Antarctic region and discussing the relationship between sea-ice variation and atmospheric circulation.