北极海冰与全球气候变化

The Arctic Sea Ice and Climate Change

最近有关北极海冰在全球气候系统中作用的研究发现，北冰洋边缘海域大洋深水的形成与海冰发育有关，海冰冻融过程对盐度层结具有重要影响，海冰变化可引起盐度突变层的灾变和热盐环流的突然停止。热盐环流的变化与北大西洋海水１０年际变化相联系，北大西洋气候的不稳定性与热盐环流变化密切相关。北极海冰海洋大气间耦合作用，使北极海冰构成了北大西洋和全球气候反馈循环中的重要环节。

This paper reviews our current state of knowledg about the Aretic sea ice climate system by highlighting recent research findings. Significant advances are being made in our understanding of roles of the Arctic sea ice in climate system. Sea ice in the Arctic ocean, which covers large areas, and its transport into the North Atlantic represents a fresh water flux comparable to that of continental runoff, affects the salinity stratification through brine rejection during freezing, transport and meiting. Salinity stratification is critical to the vertical circulation of the high latitude ocean. Variation in sea ice may cause great salinity anomaly or halocline catastrophe that can alter or stop the convection. THere is a general appreciation that the thermohaline circulation of the world ocean is to a large degree driven from the North Atlantic through the production of North Atlantic Deep Water. Evidences suggest that climate variations from decadal to millenial time scales are linked to the sea ice interaction with the thermohaline. This strong coupling between the Arctic sea ice, ocean and atmosphere implies that variation in sea ice are involved in high latitude and global climate feedback processes.