The Impact of Ocean Margin Processes in the Labrador Sea on the Atlantic Meridional Overturning Circulation

拉布拉多海是世界海洋中少数几个深水形成的地方之一。这些水从拉布拉多海输出，成为赤道翻转环流向南分支的一部分。以前的观测工作主要集中在拉布拉多海内部深对流的作用。最近的证据，从观测和数值海洋模型具体表明，海洋边界附近的过程可能是最相关的欧拉下降流的沃茨在拉布拉多海和快速出口的新改造的沃茨。我们建议分析停泊在拉布拉多海的西缘的观测与高分辨率的数值模式模拟，以了解这两个过程中发挥的作用，在副极地北大西洋的纬向翻转环流。具体来说，我们想测试（i）如果（和）下降流发生沿着拉布拉多海的边缘，（ii）如何下降流涉及到对流和涡动活动的季节性演变，（iii）如何快速沃茨新转换拉布拉多海的西缘附近的出口，以及（iv）如何这两个过程（下沉流、快速输出）影响大西洋纬向翻转环流的时间变率。

The Labrador Sea is one of the few places in the world ocean, where deep water formation takes place. This water is exported from the Labrador Sea to become part of the southward branch of the meridional overturning circulation. Previous observational work has largely focused on the role of deep convection in the interior of the Labrador Sea. Recent evidence from observations and numerical ocean models specifically indicate that processes near the ocean boundaries might be most relevant for both Eulerian downwelling of waters in the Labrador Sea and the fast export of newly transformed waters. We propose to analyze mooring based observations at the western margin of the Labrador Sea together with high resolution numerical model simulations to understand the role both processes play for the meridional overturning circulation in the subpolar North Atlantic. Specifically, we want to test (i) if (and where) downwelling occurs along the margins of the Labrador Sea, (ii) how downwelling relates to the seasonal evolution of convection and eddy activity, (iii) how fast waters newly transformed near the western margin of the Labrador Sea are exported, and (iv) how the two processes (downwelling, fast export) affect the temporal variability of the Atlantic meridional overturning circulation.