【摘要】 利用1999年美国国家冰雪资料中心的各种卫星遥感综合分析数据对楚科奇海海冰周年变化进行详细分析,将全年的海冰变化过程分成密集冰封期、东岸融化期、单湾结构期、双湾结构期、三湾结构期、全线北撤期、南进封闭期、全面冻结期8个阶段。海冰冻结期仅2个月,海冰融化期持续4～5个月,说明融冰过程的吸热是个漫长的过程。太平洋与北冰洋海面高度差形成的正压压强梯度力是白令海水进入北冰洋的主要动力,白令海水进入冰下形成的暖水海冰边缘区是海冰融化的重要机制。白令海水在楚科奇海扩散过程受到海底地形产生的Taylor柱效应的显著影响,使其产生绕过浅滩,沿海谷流动,在海谷的方向上输送更多的水体和热量的现象,形成海冰融化的湾状结构。楚科奇海的局地风场也是海冰形态变化的重要因素之一。局地风场在冬季阻碍白令海水的入流,而在夏季促进白令海水的入流。更多还原

【Abstract】 In this paper, the seasonal variations in sea ice in the Chukchi Sea are studied in detail by using the satellite remote sensing data analyzed by U.S.A. National Snow and Ice Data Center in 1999. The annual sea ice variational process can be divided into 8 stages, namely, packed ice, melting along the east coast, one-bay, two-bay, three-bay, northward retreating, southward advancing and frozen stages. The freezing process lasts only 2 months, whereas the melting process continues for 4 to 5 months, which indicates that the heat absorption in melting the sea ice takes a much longer time. The barotropic pressure gradient generated by the difference between the sea level heights of the Pacific Ocean and Arctic Ocean is the main driving force for the Bering Sea water to enter the Chukchi Sea, and the Bering Sea water inserts under the sea ice to provide more heat to the sea ice and quicken its melting. The dispersion of the Bering Sea water in the Chukchi Sea is strongly affected by the Taylor column effect of bottom topography, which drives the water to flow round the shoals and along the canyons so that more water volume and heat are transported in the canyon direction to form the bay-shaped molten ice structure. The local wind field over the Chukchi Sea is also an important factor affecting the sea ice pattern variation. The northerly wind in wintertime prevents the Bering Sea water from entering the Chukchi Sea, and the southerly wind in summertime promotes the process for the Bering Sea water to enter the Chukchi Sea.更多还原