Atlantic pycnocline theory scrutinized using a coupled climate model
Atlantic pycnocline theory scrutinized using a coupled climate model
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使用耦合气候模型仔细研究大西洋密云斜层理论
DOI：
10.1029/2010gl044180
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发表时间：
2010
影响因子：
5.2
通讯作者：
J. Fürst
中科院分区：
文献类型：
--
作者：
A. Levermann;J. Fürst
对南大洋风应力、海洋垂直混合、地表淡水强迫以及全球变暖情况进行改变后的模拟，证实了格纳纳德西肯（1999年）有关大西洋理论的基本方程：一个垂直尺度，即密度跃层深度\(D\)，与低纬度上升流成反比，与南大洋涡动输送成正比。已证实大西洋最大翻转量与\(D\)呈二次方关系，但也表明与经向密度差\(\Delta\rho\)呈线性关系。我们的模拟有力地表明，由于\(D\)和\(\Delta\rho\)的变化都很显著且相互独立，该理论需要一个关于\(\Delta\rho\)的动力学方程作为补充。在全球变暖的情况下，\(D\)变化很大，而\(\Delta\rho\)实际上保持不变；但对于改变的地表淡水通量，情况则相反。同样，南大洋露头的经向长度尺度的变化需要一个动力学方程，以便捕捉大西洋经向翻转环流的基本行为。
Simulations with changed Southern Ocean wind‐stress, oceanic vertical mixing, surface freshwater forcing and global warming confirm the basic equations of Gnanadesikan's (1999) theory for the Atlantic: one vertical scale, the pycnocline depth D, contributes inversely proportional to low‐latitudinal upwelling and linearly to Southern Ocean eddy transport. The maximum Atlantic overturning is confirmed to be quadratic in D but is also shown to be linear in a meridional density difference Δρ. Our simulations strongly suggest that the theory needs to be complemented by a dynamical equation for Δρ since changes in both D and Δρ are significant and mutually independent. While, under global warming D varies strongly and Δρ is practically constant, the situation is reversed for altered surface freshwater fluxes. Similarly, variations in the meridional length scale of Southern Ocean outcropping require a dynamical equation in order to capture the fundamental behavior of the Atlantic meridional overturning circulation.
机械驱动经向翻转环流与温盐强迫和多重平衡理论的协调
影响因子：
4.6
作者：
Johnson H
通讯作者：
Johnson H