Changes in the climate of the Arctic and the Antarctic have been of great concern to international scientific and social communities since the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) was released in 2007. Since then, many new findings have been reported from observations and research carried out in the Arctic and Antarctic during the 4th International Polar Year (IPY). There is evidence that rapid changes in the Arctic and Antarctic induced by global warming are occurring in a quantitative and qualitative sense, and Arctic and Antarctic regional changes could be used indicators of global climate change. Declining Arctic sea ice could impact on winter snowfall in much of the Northern Hemisphere, with colder winters and more snow. Projections suggest that summertime Arctic sea ice will disappear by 2040. By 2050, the Antarctic ozone hole will have recovered to the level of the early 1980s, when the production of freon was completely prohibited. With weakening the shielding effect of the ozone hole to the global warming, it will become warmer in Antarctica and East Antarctica, leading to melting of ice sheets and retreating sea ice. Sea level rise will be a serious issue. As sea surface temperature rises the air-sea exchange of CO2 will be enhanced and surface water will take up more C02. This will lead to ocean acidification with important effects on ecological systems and food chains.%政府间气候变化专门委员会(IPCC) 2007年发布了第四次评估报告,全球气候变化问题再次成为一个重要的国际科学和政治议题.2007年以来,通过实施第四次国际极地年行动所获得的成果进一步证明,全球变暖所诱发极区出现的快速变化正在经历由量到质的转变,表明两极变化对全球气候变化起着一种指示和调控作用.一些研究指出:北冰洋会在2040年前后出现夏季无海冰并将引起北半球大范围的持续暴雪的寒冷冬季发生；2050年左右南极上空臭氧空洞可能消失并恢复到20世纪80年代水平,南极地区由此会发生快速升温并引起东南极冰盖融化和海冰覆盖面积减少,使海平面升高加速；极区海水温度快速升高会驱动极区表层海洋和上覆大气之间的CO2分压加速平衡,极区海洋吸收大气CO2并储存增多,并诱发海洋酸化从而损坏海洋生态系统和食物网.
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