1. Thermohaline circulation crisis and impacts during the mid-Pleistocene transition.
- Author
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Pena, Leopoldo D. and Goldstein, Steven L.
- Subjects
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MERIDIONAL overturning circulation , *PALEOCEANOGRAPHY , *GLACIAL climates , *OCEAN circulation , *PLEISTOCENE paleoclimatology , *GLACIATION - Abstract
The mid-Pleistocene transition (MPT) marked a fundamental change in glacial-interglacial periodicity, when it increased from ~41-thousand-year to 100-thousand-year cycles and developed higher-amplitude climate variability without substantial changes in the Milankovitch forcing. Here, we document, by using Nd isotopes, a major disruption of the ocean thermohaline circulation (THC) system during the MPT between marine isotope stages (MISs) 25 and 21 at ~950 to 860 thousand years ago, which effectively marks the first 100-thousand-year cycle, including an exceptional weakening through a critical interglacial (MIS 23) at ~900 thousand years ago. Its recovery into the post-MPT 100-thousand-year world is characterized by continued weak glacial THC. The MPT ocean circulation crisis facilitated the coeval drawdown of atmospheric CO2 and high-latitude ice sheet growth, generating the conditions that stabilized 100-thousand-year cycles. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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