在1999年7月至9月的中国首次北极科学考察中, 对北极密集冰区进行了航空数字相机遥感观测, 获得一批高分辨率的不同类型海冰数字影像。探讨了利用数字影像分析海冰形态参数的方法。利用这些方法不仅可以分析海冰边缘、密集度、冰水比例等常规参数, 而且可以获得卫星遥感尚无法探测的一些海冰形态的新参数, 这些参数将增加对不同类别海冰的认识, 对于研究北极融冰过程和冰区的海气相互作用提供有价值的手段和分析方法。给出的方法可以应用到中国渤海海冰和其它海域海冰的研究。

In the Chinese Arctic scientific expedition during Jul y to September, 1999, a set of digital images by helicopter remote sensing are o btained. With high ground resolution of 30 cm, these images can be used to analy ze detailed sea ice parameters. In this paper, a method for determining the thr eshold value is adopted to separate ice and water. A ratio of radiance is de fined as the ratio of the ice element number that with large difference compared with the neighbor element over the total element number with the same radiance value. By the result, not only ice edge and ice concentration are accurately cal culated, but some new parameters are also chosen to present the status of sea i ce. Ice area is a parameter to give the area of each ice to show the size of ice. Sea ice is divided into five types by its area size to show the ice dis tribution ratio in different types. As many big ice packs consist of small ice pieces crowded each other, a new parameter called breaking degree is propos ed to express the complexion degree of ice shape. These parameters can be used t o distinguish ice size in a big ice, which can greatly affect vessel navigation and air-ice-ocean heat exchange. By combining these parameters, people can get more information of sea ice for its concentration, area of big ice and broken degree of ice pack. It seems that these parameters are useful in the studies in ice melting process and interaction between atmosphere and ocean water. These pa rameters are hardly determined by satellite imagery. The method can be used to c alculate water's area, and complexion degree of water regions to express lead, l ane, polynya, etc. The methods can be used in sea ice analysis for either polar ice or the ice in Bohai Sea.