南极海冰与气候

在极区，海冰的形成在海洋上部和大气下部之间构成了新的交界面，改变了大洋表面的辐射平衡和能量平衡，隔离了海洋与大气之间的热交换和水汽交换；海冰冻融过程影响着大洋温、盐流的形成和强度；海冰对南大洋和南极大陆气象、气候有重要的影响，在气候环境系统中起着重要的作用。南极海冰作用区约占南半球雪冰作用区面积的58%，约占地球表面积的3.58%。其中，一年生海冰约占南极海冰区分布面积的83%；其分布面积从夏末2月份最小时的3×106 km2左右，到9月份冬末最大时的18×106 km2左右，一年中季节变化幅度可达15×106 km2，季节变化率>500%。海冰分布区域的年际变化较大。南极海冰区是影响季节和年际全球气候环境变化的重要区域。当前，国际南极海冰与气候研究的核心问题是海冰物理过程和在海冰区的海洋—大气相互作用。结合目前承担的研究课题，对国际南极海冰与气候研究的前沿动态和相关的国际计划进行了综述。

ANTARCTIC SEA ICE AND CLIMATE

The sea ice frozen on polar ocean forms a new interface between the upper ocean and the lower atmosphere. Sea ice plays an important part in the climate and environment system of Earth through its modifying role in radiative and energy balances, prevent the exchange of heat and moisture between the ocean and atmosphere. The salt reject during processes of sea ice freezing affects the ocean structure and circulation. Sea ice also affects the weather and climate at the South Ocean and Antarctic continent. The area of Antarctic sea ice takes about 58% of all the area of south hemisphere cryosphere, and 3.58% of Earth surface area. The seasonal sea ice area in Antarctica is about 83% of all sea ice area. The area of sea ice in Antarctica decreases to the smallest, about 3×106km2, at February in the end of Austral summer; the area increases to the largest, around 18×106km2，at September in the end of Austral winter, the fluctuant range for one year living sea ice is about 15×106km2. The seasonal change of sea ice is larger than 500%, one of the greatest seasonal surface changes on Earth. The inter annual variations of sea ice zones are big. Antarctic sea ice area is one of key regions, which affect the global climate and environment in season and inter annual. To understand sea ice processes and the interactions between ocean and atmosphere in sea ice area are the main objectives of international Antarctic sea ice and climate programs. Some progresses of research on sea ice and clime, and international programs on Antarctic sea ice are reviewed.