Solar forcing synchronizes decadal North Atlantic climate variability

Quasi-decadal variability in solar irradiance has been suggested to exert a substantial effect on Earth’s regional climate. In the North Atlantic sector, the 11-year solar signal has been proposed to project onto a pattern resembling the North Atlantic Oscillation (NAO), with a lag of a few years du...

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Bibliographic Details
Published in:Nature Communications
Main Authors: Thieblemont, Remi, Matthes, Katja, Omrani, Nour-Eddine, Kodera, Kunihiko, Hansen, Felicitas
Format: Article in Journal/Newspaper
Language:English
Published: Nature Publishing Group 2015
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Online Access:https://oceanrep.geomar.de/id/eprint/29890/
https://oceanrep.geomar.de/id/eprint/29890/1/ncomms9268.pdf
https://doi.org/10.1038/ncomms9268
Description
Summary:Quasi-decadal variability in solar irradiance has been suggested to exert a substantial effect on Earth’s regional climate. In the North Atlantic sector, the 11-year solar signal has been proposed to project onto a pattern resembling the North Atlantic Oscillation (NAO), with a lag of a few years due to ocean-atmosphere interactions. The solar/NAO relationship is, however, highly misrepresented in climate model simulations with realistic observed forcings. In addition, its detection is particularly complicated since NAO quasi-decadal fluctuations can be intrinsically generated by the coupled ocean-atmosphere system. Here we compare two multi-decadal ocean-atmosphere chemistry-climate simulations with and without solar forcing variability. While the experiment including solar variability simulates a 1–2-year lagged solar/NAO relationship, comparison of both experiments suggests that the 11-year solar cycle synchronizes quasi-decadal NAO variability intrinsic to the model. The synchronization is consistent with the downward propagation of the solar signal from the stratosphere to the surface.