Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes

@article{McManus2004CollapseAR,
  title={Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes},
  author={Jerry F. McManus and Roger Francois and J. M. Gherardi and L. D. Keigwin and S. L. R. Brown-Leger},
  journal={Nature},
  year={2004},
  volume={428},
  pages={834-837}
}
The Atlantic meridional overturning circulation is widely believed to affect climate. Changes in ocean circulation have been inferred from records of the deep water chemical composition derived from sedimentary nutrient proxies, but their impact on climate is difficult to assess because such reconstructions provide insufficient constraints on the rate of overturning. Here we report measurements of 231Pa/230Th, a kinematic proxy for the meridional overturning circulation, in a sediment core from… 

Estimated strength of the Atlantic overturning circulation during the last deglaciation

The Atlantic meridional overturning circulation affects the latitudinal distribution of heat, and is a key component of the climate system. Proxy reconstructions, based on sedimentary 231 Pa= 230 Th

Extreme deepening of the Atlantic overturning circulation during deglaciation

Glacial terminations during the late Pleistocene epoch are associated with changes in insolation. They are also punctuated by millennial-scale climate shifts, characterized by a weakening and

Constraining the Variability of the Atlantic Meridional Overturning Circulation During the Holocene

There is a converging body of evidence supporting a measurable slowdown of the Atlantic Meridional Overturning Circulation (AMOC) as climate warms and Northern Hemisphere ice sheets inexorably

Accelerated drawdown of meridional overturning in the late‐glacial Atlantic triggered by transient pre‐H event freshwater perturbation

Abrupt decreases of the Atlantic meridional overturning circulation (MOC) during the Late Pleistocene have been directly linked to catastrophic discharges of glacimarine freshwater, triggering

Coherent deglacial changes in western Atlantic Ocean circulation

A consistent signal of the 231Pa/230Th proxy reveals a spatially coherent picture of western Atlantic circulation changes over the last deglaciation, which reveals a two-step AMOC slowdown at the beginning of the deglacial period.

Strength and geometry of the glacial Atlantic Meridional Overturning Circulation

During the Last Glacial Maximum, the pattern of Atlantic Meridional Overturning Circulation was different from today. A combination of sediment chemistry and a scavenging model suggests that the

North Atlantic ocean circulation and abrupt climate change during the last glaciation

Climate and ocean circulation proxies are examined at high resolution in a deep North Atlantic sediment core, suggesting reduced Atlantic overturning circulation during every cool northern stadial, with the greatest reductions during episodic Hudson Strait iceberg discharges, while sharp northern warming followed reinvigorated overturning.

Abrupt pre-Bølling–Allerød warming and circulation changes in the deep ocean

It is shown that the release of heat from warm waters in the deep North Atlantic Ocean probably triggered the Bølling–Allerød warming and reinvigoration of the Atlantic meridional overturning circulation, and the depleted radiocarbon content of the warm and salty water mass implies a long-term disconnect from rapid surface exchanges, and is most consistent with a Southern Ocean source.
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