The Beaufort Gyre variation and its impacts on the Canada Basin in 2003–2012
The Beaufort Gyre variation and its impacts on the Canada Basin in 2003–2012
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DOI：
10.1007/s13131-015-0657-0
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发表时间：
2015-07
影响因子：
1.4
通讯作者：
Wenli Zhong;Jinping Zhao;Jiuxin Shi;Yong Cao
中科院分区：
文献类型：
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作者：
Wenli Zhong;Jinping Zhao;Jiuxin Shi;Yong Cao
博福特环流（BG）是近10年来形成的，是控制海洋上层变化的重要因素。在加拿大海盆，上层海洋的热含量和淡水含量逐渐增加，动量输入也逐渐增加。地转风旋度和淡水含量都对BG的旋转起作用。然而，即使风场没有变化，淡水的增加也会导致BG的旋转。在这项研究中，我们表明，太平洋水是很难流入中央盆地作为BG旋转和太平洋夏季水（PSW）的最高温度经历了一个戏剧性的下降，在2005年和2009年内BG由于PSW的流动路径的变化。埃克曼抽水系统的加强，积聚了更多淡水，令太平洋冬季海水的深度加深。水柱动态的这种变化也导致了2007年后大西洋水核心的加深。EP在2012年显著下降（表明BG的旋转下降），Ekman运输的方向转向北方，这有利于释放多年来一直存在于流域中的淡水。
The Beaufort Gyre (BG) was spun up in the last decade which is an important factor in regulating the variation of the upper ocean. The heat content and freshwater content of the upper ocean increased gradually in the Canada Basin, as did momentum input. Both the geostrophic wind curl and freshwater content could contribute to the spin-up of BG. However, even though there is no change of the wind field the increasing freshwater alone could result in the spin-up of BG. In this study we show that the Pacific Water is difficult to flow into the central basin as the BG spins up and the maximum temperature of the Pacific Summer Water (PSW) experienced a dramatic decrease inside the BG in 2005 and 2009 due to a change of flow pathway of PSW. The enhancement of Ekman Pumping (EP) contributed to the deepening of the Pacific Winter Water by piling up more freshwater. This change of water column dynamics has also contributed to the deepening ofthe Atlantic Water core after 2007. The EP decreased significantly in 2012 (indicating a spin down of BG) and the direction of Ekman transport turned to the north, which favoured the release of freshwater that had resided in the basin for years.