Michel S. L. L., Swingedouw D., Ortega P., Gastineau G., Mignot Juliette, McCarthy G., Khodri Myriam. (2022). Early warning signal for a tipping point suggested by a millennial Atlantic Multidecadal Variability reconstruction. Nature Communications, 13 (1), 5176 [14 p.].
Titre du document
Early warning signal for a tipping point suggested by a millennial Atlantic Multidecadal Variability reconstruction
Michel S. L. L., Swingedouw D., Ortega P., Gastineau G., Mignot Juliette, McCarthy G., Khodri Myriam
Source
Nature Communications, 2022,
13 (1), 5176 [14 p.]
Atlantic multidecadal variability is a coherent mode of natural climate variability occurring in the North Atlantic Ocean, with strong impacts on human societies and ecosystems worldwide. However, its periodicity and drivers are widely debated due to the short temporal extent of instrumental observations and competing effects of both internal and external climate factors acting on North Atlantic surface temperature variability. Here, we use a paleoclimate database and an advanced statistical framework to generate, evaluate, and compare 312 reconstructions of the Atlantic multidecadal variability over the past millennium, based on different indices and regression methods. From this process, the best reconstruction is obtained with the random forest method, and its robustness is checked using climate model outputs and independent oceanic paleoclimate data. This reconstruction shows that memory in variations of Atlantic multidecadal variability have strongly increased recently-a potential early warning signal for the approach of a North Atlantic tipping point. This study presents a last millennium reconstruction of Atlantic Multidecadal Variability fluctuations. This sufficiently long and validated reconstruction suggests the potential approach of a tipping point in the North Atlantic current system.
Plan de classement
Sciences du milieu [021]
;
Limnologie physique / Océanographie physique [032]
