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Deglaciations and glacial inceptions are the two equally important transitional periods that bridge the glacial and interglacial climate states, yet our understanding of deglaciations far exceeds that of glacial inceptions. Substantial variations in deep ocean circulation accompanied the last deglaciation, and model simulations recently suggested that a weakening of the Atlantic Meridional Overturning Circulation (AMOC) also occurred at the last glacial inception (LGI; 113-119 thousand years ago), yet evidence of such a change remains inconclusive. Here, we report three Pa/Th records from the western and central North Atlantic that display an abrupt weakening of the AMOC at the LGI. The magnitude of the reconstructed AMOC weakening approaches but never reaches the level of disruptions associated with the Heinrich ice discharge events. Our results may highlight a unique period of orbitally forced abrupt circulation changes and the importance of ocean processes in setting atmospheric CO changes in motion.
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http://dx.doi.org/10.1038/s41467-025-62960-y | DOI Listing |
Sci Rep
August 2025
Space Physics Laboratory, Vikram Sarabhai Space Centre, Department of Space, Government of India, Indian Space Research Organisation, Thiruvananthapuram, 695022, India.
Solar eclipses induce abrupt reductions in solar radiation, triggering notable changes in the atmospheric boundary layer (ABL). This study employs large eddy simulations (LES) to investigate eclipse-induced ABL modulations over Thiruvananthapuram during the annular solar eclipse of 15 January 2010. Unlike previous studies that primarily relied on observational analyses, this work provides a first-of-its-kind numerical simulation of such phenomena using a state-of-the-art LES framework.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2025
Department of Earth Sciences, University of Utrecht, Utrecht 3584 CD, The Netherlands.
The Mediterranean basin reconnected to the Atlantic Ocean ~5.33 Myr ago, following its partial desiccation during the preceding Messinian salinity crisis (5.97 to 5.
View Article and Find Full Text PDFNat Commun
August 2025
Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA.
Deglaciations and glacial inceptions are the two equally important transitional periods that bridge the glacial and interglacial climate states, yet our understanding of deglaciations far exceeds that of glacial inceptions. Substantial variations in deep ocean circulation accompanied the last deglaciation, and model simulations recently suggested that a weakening of the Atlantic Meridional Overturning Circulation (AMOC) also occurred at the last glacial inception (LGI; 113-119 thousand years ago), yet evidence of such a change remains inconclusive. Here, we report three Pa/Th records from the western and central North Atlantic that display an abrupt weakening of the AMOC at the LGI.
View Article and Find Full Text PDFCommun Earth Environ
August 2025
Department of Earth and Planetary Sciences, Institute of Geophysics, ETH Zürich, Sonneggstrasse 5, 8092 Zürich, Switzerland.
Subduction initiation is a pivotal process in the Wilson cycle, yet its mechanisms remain elusive. Using 3D coupled thermo-mechanical and surface processes models, we investigated how the duration of the plate motion reversal from rifting to plate convergence and the structural versus thermal inheritance influence the location of compression-induced subduction initiation. Our results reveal that abrupt plate motion changes lead to ridge inversion-driven subduction, controlled by the inherited thermal- and melt-induced weakening.
View Article and Find Full Text PDFScience
July 2025
H. Holden Thorp is Editor-in-Chief of the Science journals.
In the last few weeks, has published commentary condemning and supporting the Restoring Gold Standard Science executive order from the Trump administration that purports to strengthen research integrity in the United States through greater government oversight. The scientific community has largely reacted negatively to the directive, fearing that the way oversight by political appointees is specified in the order will lead to interference in the curiosity-driven process of science. This distress is understandable given the administration's abrupt and arbitrary actions to cut research funding and curtail or even stop the participation of foreign students in research.
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