Progress in Climate Change Sciences The Role of the Thermohaline Circulation in Climate Change

• Main Author: Zhou Tianjun
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: regional climate (Zhou; et al; 2000; Wang; 2004; North Atlantic; North atlantic Thermohaline circulation
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.557.7320; http://www.lasg.ac.cn/staff/ztj/paper-e/2004thc_review.pdf

Satellite measurements of the Earth radiation budget reveal the surplus of incoming absorbed solar energy over outgoing longwave radiation in low latitudes, while the reverse is true at high latitudes on an annual mean bias. Thus, radiative processes are continually acting to cool the high latitudes and warm the low latitudes, and it is only the poleward heat transport that serves to offset the energy loss, in which, the oceanic poleward heat transport has great contributions. Under current climate system, the Atlantic Ocean plays a key role in transporting heat from tropics to high latitudes, which is mainly due to the existence of the meridional overturning circulation, namely thermohaline circulation (Broecker, 1991). Circulation of the 90 % of ocean water beneath the surface zone is driven by the force of gravity as dense water sinks and less dense water rises. Since the ocean water density is largely a function of temperature and salinity, the movement of deep water drived from the density gradient is called “Thermohaline Circulation”. In comparison with other regions of same latitudes, the wintertime North Europe experienced a warmer climate (Fig. 1,see color page 4), partially due to the climate impact of the North Atlantic thermohaline circulation by transporting meridional heat (Bryden, 1993). Any kinds of potential changes of the thermohaline circulation would cause serious impacts on the northern Europe