中文摘要：

在过去30年间，北极气候发生了前所未有的异常变化，北极海冰变化更是经历了令人瞩目的、从平缓到突变的缩减过程，因此，北冰洋及其海冰的研究得到广泛的重视。综述当前国内外有关北极海冰快速变化的研究工作，对这些大气的现场观测和卫星遥感资料的分析，以及一些全球和区域气候模拟的结果，基本上一致地指出了近30年来北极海冰的快速衰减趋势，尤其是夏季北极海冰正以每10年超过10％的变化幅度快速减少。从海冰的基本物理特征、与大气海洋相互作用的物理过程、及其对全球和北极气候变化的响应和反馈机制，研究形成这种快速变化的因子——海表面气温增暖，太平洋与大西洋人流的热盐性质变化，以及大气环流模态的影响等。

英文摘要：

In the past 30 years, a large-scale change occurred in the Arctic climatic system, which had never been observed before 1980s. At the same time, the Arctic sea ice experienced a special evolution with more and more rapidly dramatic declining. In this circumstance, the Arctic sea ice became a new focus of the Arctic research. The recent advancements about abrupt change of the Arctic sea ice are reviewed in this paper. The previous analyses have demonstrated the accelerated declining trend of Arctic sea ice extent in the past 30 years, based on in-situ and satellite-based observations of atmosphere, as well as the results of global and regional climate simulations. Especially in summer, the rate of decrease for the ice extents was above 10% per decade. Furthermore, we discuss the evolution characteristics of the Arctic sea ice and its possible cause from three aspects, i.e. the sea ice physical properties, the interaction process of sea ice, ocean and atmosphere and its response and feedback mechanism to global and Arctic climate system.