收稿日期: 2002-08-23
修回日期: 2003-01-28
网络出版日期: 2003-06-01
基金资助
国家自然科学基金项目“北冰洋多年变化及其机理的综合研究”(编号:49879008)资助.
ADVANCES IN STUDIES ON THE ARCTIC HALOCLINE
Received date: 2002-08-23
Revised date: 2003-01-28
Online published: 2003-06-01
长年存在的盐跃层是北冰洋上层海洋独有的结构之一,对维持北冰洋表层的低温特征和海冰存在起着非常重要的作用。在过去的十几年中,北冰洋气候系统发生了前所未有的异常变化,北冰洋盐跃层也经历了从消退到近乎恢复的戏剧性变化。因此,北冰洋及其盐跃层的研究得到了广泛的重视。介绍了有关北冰洋盐跃层研究的进展情况,并对研究中存在的问题以及未来的发展进行了分析和阐述。有关北冰洋盐跃层的形成问题,先后有平流机制、对流机制等多种观点。认为由于现在欧亚海盆表层盐度普遍增高,其盐跃层的形成当以对流机制为主;而平流机制则更加适用于加拿大海盆的盐跃层。20世纪90年代,在北冰洋观测到一系列异常变化,包括盐跃层退缩、大西洋层增暖和北极海冰减少。实际上,这些变化是紧密联系在一起的,而后期盐跃层局部性的恢复似乎表明目前观测到的北冰洋气候系统的变化有可能是一种周期性的振荡。
赵进平 , 史久新 . 北冰洋盐跃层研究进展[J]. 地球科学进展, 2003 , 18(3) : 351 -357 . DOI: 10.11867/j.issn.1001-8166.2003.03.0351
The permanent Arctic halocline, one of the particular structures in the upper Arctic ocean, is very important to the maintenance ofthe sea ice and cold surface layer in the Arctic ocean. In the last decade, a large-scale change occurred in the Arctic climatic system, which had never been observed before 1990s. At the same time, the Cold Halocline Layer (CHL) of the Arctic ocean experienced a special evolution with disappearing at the early 1990s and then partially recovering in 1998. In this circumstance, the Arctic halocline became a new focus of the Arctic ocean research. The recent advances in the studies on the Arctic halocline, including the mechanism for its formation and observations of its inter-annual variations, were reviewed in this paper. The unsolved problems in the previous research works and possible advances in the future studies were also commented.
Several theories of the formation for the Arctic halocline had been presented, such as “Advective CHL” and “Convective CHL”. Because the surface salinity in the Eurasia basin had increased, the CHL in the Eurasia basin should be “Convective CHL”. The “Advective CHL” mechanism might be suitable for the halocline in the Canada basin as its characteristics is quite different from that of the CHL in the Eurasia basin. Since 1990s, a series of anomalous variations had been found,such as the retreating of CHL, the warming of the Atlantic layer and the decreasing of the Arctic sea ice. In fact, all these variations are connected closely.The partial recovery of the Arctic halocline implied that the observed variations in the Arctic climatic system could be a kind of periodical oscillation.
Key words: Halocline; Arctic ocean; Inter-annual variation.
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