Skip to Main content Skip to Navigation
Journal articles

Abrupt cooling over the North Atlantic in modern climate models

Abstract : Observations over the 20th century evidence no long-term warming in the subpolar North Atlantic (SPG). This region even experienced a rapid cooling around 1970, raising a debate over its potential reoccurrence. Here we assess the risk of future abrupt SPG cooling in 40 climate models from the fifth Coupled Model Intercomparison Project (CMIP5). Contrary to the long-term SPG warming trend evidenced by most of the models, 17.5% of the models (7/40) project a rapid SPG cooling, consistent with a collapse of the local deep-ocean convection. Uncertainty in projections is associated with the models' varying capability in simulating the present-day SPG stratification, whose realistic reproduction appears a necessary condition for the onset of a convection collapse. This event occurs in 45.5% of the 11 models best able to simulate the observed SPG stratification. Thus, due to systematic model biases, the CMIP5 ensemble as a whole underestimates the chance of future abrupt SPG cooling, entailing crucial implications for observation and adaptation policy.
Document type :
Journal articles
Complete list of metadatas

Cited literature [74 references]  Display  Hide  Download

https://hal-cea.archives-ouvertes.fr/cea-02138768
Contributor : Bruno Savelli <>
Submitted on : Friday, May 24, 2019 - 10:16:05 AM
Last modification on : Friday, September 18, 2020 - 2:34:48 PM

File

lee.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Giovanni Sgubin, Didier Swingedouw, Sybren Drijfhout, Yannick Mary, Amine Bennabi. Abrupt cooling over the North Atlantic in modern climate models. Nature Communications, Nature Publishing Group, 2017, 8, pp.14375. ⟨10.1038/ncomms14375⟩. ⟨cea-02138768⟩

Share

Metrics

Record views

275

Files downloads

793