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Climate network characterization of the Atlantic Meridional Overturning Circulation edge state

Laure Moinat1,2, Reyk Börner3, Valerio Lucarini4,5, Maura Brunetti1,2, and Henk A. Dijkstra3

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Phys. Rev. Research 8, 033268 – Published 3 September, 2026

DOI: https://doi.org/10.1103/q9bd-4h4j

Abstract

This article is part of a Physical Review Collection on the Physics in a Changing Climate.

The Atlantic Meridional Overturning Circulation (AMOC) has been identified as a tipping element in the Earth system. Under the current climate change scenarios, it is urgent to develop robust methods for determining the probability of future AMOC transitions. Recent studies using an Earth system model of intermediate complexity (EMIC) have revealed the importance of an AMOC edge state, located on the boundary of the attraction basin of the collapsed state, in AMOC transitions. Here, we provide a characterization of this edge state through climate networks, using instantaneous temporal correlations between geographical locations to define the network links. We apply the climate network analysis to a set of EMIC simulations with CO2 forcing according to an intermediate climate change scenario (SSP2-4.5), which exhibit qualitatively different AMOC responses as a result of interaction with the edge state. We show that network measures, specifically the normalized degree centrality, reveal the presence of teleconnections across the equator as the AMOC approaches the edge state. A similar result is obtained for an Earth system model (ESM) simulating AMOC collapse or recovery, suggesting that climate networks could be used to detect an AMOC instability in ESMs and observations.

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This article appears in the following collection:

Physics in a Changing Climate

Climate Science is a growing field that is attracting colleagues from many disciplines. This Collection, a joint effort by Physical Review E, Physical Review Research, and PRX Energy curated by Prof. Justin Burton from Emory University, aims at providing a survey of the diverse range of topics that scientists with a connection to Physics are exploring in this exciting area of research. This includes climate and related geosciences, sustainability, energy, and material science, and may include fundamental as well as applied research.

Every article in this Collection was subjected to a rigorous peer review process, upholding the high standards applied to all papers. The Physical Review E, Physical Review Research, and PRX Energy editorial teams managed the peer review and made all editorial decisions.

Article Text

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Outline

Information

Phys. Rev. Research 8, 033268– Published 3 September, 2026
  • Received 7 June 2026
  • Accepted 11 August 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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