Strength and geometry of the glacial Atlantic Meridional Overturning Circulation
Strength and geometry of the glacial Atlantic Meridional Overturning Circulation
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冰川大西洋经向翻转环流的强度和几何形状
DOI：
10.1038/ngeo1608
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发表时间：
2012
影响因子：
18.3
通讯作者：
H. Schulz
中科院分区：
文献类型：
--
作者：
Lippold;Y. Luo;R. Francois;S. Allen;J. Gherardi;S. Pichat;B. Hickey;H. Schulz
大西洋经向翻转环流的强度和几何形状与冰期-间冰期和千年时间尺度上的气候密切相关，但事实证明很难重建，特别是在最后一次冰盛期。今天，与大西洋经向翻转环流有关的从北大西洋北部返回到较低纬度的流量约为4,000 米。相比之下，在最后一次冰盛期，这种返回流量被认为主要发生在较浅的深度。对沉积物231Pa230th的测量已经被用来重建北大西洋的环流强度，但生物成因二氧化硅对基于231Pa230th的估计的影响仍然存在争议。在这里，我们利用全新世大西洋沉积物中231Pa230th比值和生物硅的测量以及二维清扫模型的模拟来证明，大西洋经向翻转环流的几何形状和强度是现代大西洋沉积物231Pa230th比值的主要控制因素。对于冰川高峰期，模拟的大西洋翻转具有浅但强劲的环流和大约2,000 m深度的大量水输送，与冰川大西洋231Pa230th的观测值最吻合。我们估计，在最后一次冰川盛期，中间水的输送至少与今天的深水输送一样强大。
The strength and geometry of the Atlantic meridional overturning circulation is tightly coupled to climate on glacial–interglacial and millennial timescales, but has proved difficult to reconstruct, particularly for the Last Glacial Maximum. Today, the return flow from the northern North Atlantic to lower latitudes associated with the Atlantic meridional overturning circulation reaches down to approximately 4,000 m. In contrast, during the Last Glacial Maximum this return flow is thought to have occurred primarily at shallower depths. Measurements of sedimentary231Pa/230Th have been used to reconstruct the strength of circulation in the North Atlantic Ocean,, but the effects of biogenic silica on231Pa/230Th-based estimates remain controversial. Here we use measurements of231Pa/230Th ratios and biogenic silica in Holocene-aged Atlantic sediments and simulations with a two-dimensional scavenging model to demonstrate that the geometry and strength of the Atlantic meridional overturning circulation are the primary controls of231Pa/230Th ratios in modern Atlantic sediments. For the glacial maximum, a simulation of Atlantic overturning with a shallow, but vigorous circulation and bulk water transport at around 2,000 m depth best matched observed glacial Atlantic231Pa/230Th values. We estimate that the transport of intermediate water during the Last Glacial Maximum was at least as strong as deep water transport today.
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回复S. Peacock关于“根据北大西洋地区231Pa/230Th沉积记录推断的冰期-间冰期环流变化”的评论
影响因子：
--
作者：
J. Gherardi;Yiming Luo;R. Francois;J. McManus;S. Allen;L. Labeyrie
通讯作者：
L. Labeyrie
影响因子：
56.9
作者：
J. Lynch‐Stieglitz;J. Adkins;W. Curry;T. Dokken;I. Hall;J. Herguera;J. Hirschi;E. Ivanova;
通讯作者：
J. Lynch‐Stieglitz;J. Adkins;W. Curry;T. Dokken;I. Hall;J. Herguera;J. Hirschi;E. Ivanova;
影响因子：
--
作者：
E. Kwon;M. Hain;D. Sigman;E. Galbraith;J. Sarmiento;J. Toggweiler
通讯作者：
J. Toggweiler
DOI：
10.1016/j.nimb.2009.10.123
发表时间：
2010-04-01
影响因子：
1.3
作者：
Christl, Marcus;Lippold, Joerg;Synal, Hans-Arno
通讯作者：
Synal, Hans-Arno
影响因子：
5.2
作者：
Hall, I. R.;Moran, S. B.;Edwards, R. L.
通讯作者：
Edwards, R. L.