Arctic circulation regimes.
Arctic circulation regimes.
复制标题
DOI：
10.1098/rsta.2014.0160
复制
发表时间：
2015-10-13
期刊：
影响因子：
--
通讯作者：
Bamber JL
中科院分区：
文献类型：
--
作者：
Proshutinsky A;Dukhovskoy D;Timmermans ML;Krishfield R;Bamber JL
1948年至1996年期间，北极的年平均环境参数经历了明显的十年变化，有两种基本的环流模式：气旋和反气旋交替，每隔5至7年。在气旋期间，低海平面大气压力（SLP）主导了北冰洋，推动海冰和上层海洋逆时针运动;北极大气相对温暖潮湿，从北冰洋流向亚北极海的淡水通量增强。相反，在反气旋环流制度，高SLP占主导地位的驱动海冰和海洋上层顺时针。与此同时，大气寒冷干燥，从北极到亚北极海的淡水通量减少。然而，自1997年以来，北极系统一直受到反气旋环流制度（17年）的影响，其环境参数对这一制度来说是非典型的。我们讨论了一个解释北极环流制度的强度和持续时间的原因和机制的假设，并推测如何从北冰洋和格陵兰岛的淡水通量的变化影响环境条件和中断其十年变化。
Between 1948 and 1996, mean annual environmental parameters in the Arctic experienced a well-pronounced decadal variability with two basic circulation patterns: cyclonic and anticyclonic alternating at 5 to 7 year intervals. During cyclonic regimes, low sea-level atmospheric pressure (SLP) dominated over the Arctic Ocean driving sea ice and the upper ocean counterclockwise; the Arctic atmosphere was relatively warm and humid, and freshwater flux from the Arctic Ocean towards the subarctic seas was intensified. By contrast, during anticylonic circulation regimes, high SLP dominated driving sea ice and the upper ocean clockwise. Meanwhile, the atmosphere was cold and dry and the freshwater flux from the Arctic to the subarctic seas was reduced. Since 1997, however, the Arctic system has been under the influence of an anticyclonic circulation regime (17 years) with a set of environmental parameters that are atypical for this regime. We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from the Arctic Ocean and Greenland impact environmental conditions and interrupt their decadal variability.