极地海冰对全球气候变化具有指示作用,北极海冰监测对全球气候环境变化研究意义重大.利用中国第3次北极科学考察(CHINARE-2008)期间布放的海冰物质平衡浮标所获取的数据和MODIS影像,对北极海冰运动及其变化进行监测.结果表明利用MODIS影像反演的海冰密集度图像效果较好,对海冰和海水的判别精度高.海冰密集度及其漂移速度总体都呈下降趋势,两者的变化存在相关关系.海冰自西北向东南方向的运动轨迹与2009年北极年平均海面风成流的环流模式基本一致,同时海冰表面的冰间水道主要呈西北一东南走向,说明海冰总体的运动变化受到风场和洋流的影响.通过对海冰密集度异常值和海冰运动轨迹细节的研究,得出海冰表面形态和密集度的变化也主要与风和洋流有关,此外,还有来自地形条件的直接和间接的影响.%Polar sea-ice has an important impact on the global climate, and the monitoring of Arctic sea-ice is a critical component of the study of global climate change. On the basis of 1MB data which was acquired during the CHIN-ARE-2008 and MODIS images, the Arctic sea-ice motion and changes were investigated. The results showed that the effect of sea-ice concentration images which were inversed by using MODIS images was good. And the accuracy of discrimination between sea-water and sea-ice was high. There was a general downward trend in both sea-ice concentration and drifting speed, and they were related to each other. The track of sea-ice from northwest to southeast was consistent with the 2009 annual surface circulation pattern of wind-driven currents in the Arctic. The ice-free lanes also ran in a northwest to southeast direction, indicating that the general change in sea-ice movement was influenced by wind fields and ocean currents. We investigated the outliers of sea-ice concentration and plots of sea-ice tracks, and concluded that surface morphology and variations in sea-ice concentration were also related to winds and ocean currents as well as being directly or indirectly affected by topographic conditions.
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