Geophysical Research Letters

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A Signal of Persistent Atlantic Multidecadal Variability in Arctic Sea Ice
Geophysical Research Letters

Satellite data suggest an Arctic sea ice–climate system in rapid transformation, yet its long-term natural modes of variability are poorly known. Here, we integrate and synthesize a set of multi-century historical records of Atlantic Arctic sea ice, supplemented with high-resolution paleo proxy records, each reflecting primarily winter/spring sea ice conditions. We establish a signal of pervasive and persistent multidecadal (~60–90 year) fluctuations that is most pronounced in the Greenland Sea, and weakens further away. Covariability between sea ice and Atlantic multidecadal variability as represented by the Atlantic Multidecadal Oscillation (AMO) index is evident during the instrumental record, including an abrupt change at the onset of the early 20th century warming (ETCW). Similar covariability through previous centuries is evident from comparison of the longest historical sea ice records and paleo proxy reconstructions of sea ice and the AMO. This observational evidence supports recent modelling studies that have suggested that Arctic sea ice is intrinsically linked to Atlantic multidecadal variability. This may have implications for understanding the recent negative trend in Arctic winter sea ice extent, although because the losses have been greater in summer, other processes and feedbacks are also important.

Pour ceux qui se sont perdus dans le jargon scientifique, cette étude montre que la diminution de glace au Pôle Nord ne peut pas être entièrement imputée au réchauffement climatique. Selon les évidences recueillies, une variation naturelle du climat, qui a souvent été observée dans le passé (des cycles de ~60–90 ans), serait le principal facteur.

Donc, n’en déplaise aux réchauffistes, le Père Noël n’a rien à craindre… M’enfin, pour ces gens, faire de la démagogie est plus facile que de lire un article scientifique…

Bien entendu, personne dans les médias ne parlera de cet article, il ne faudrait pas briser l’illusion d’un consensus.