TY - JOUR
T1 - Connecting the Atlantic Meridional Overturning Circulation to the Southern Ocean Following the Closure of Equatorial Seaways During the Cenozoic
AU - Pineau, Erwan
AU - Lique, Camille
AU - Ferreira, David
AU - Huck, Thierry
AU - Ladant, Jean‐Baptiste
AU - Fabre, Emma
AU - Millot‐Weil, Jeanne
AU - Donnadieu, Yannick
N1 - Publisher Copyright:
© 2026 The Author(s).
PY - 2026/1/28
Y1 - 2026/1/28
N2 - Global ocean circulation regulates climate and has undergone significant changes over the Cenozoic. Today, the Atlantic Meridional Overturning Circulation (AMOC) is driven by North Atlantic Deep Water (NADW) formation and Southern Ocean upwelling. By contrast, during the middle Eocene to early Oligocene (48–28 Ma), a restricted Drake Passage was limiting the northern Ekman transport, while a circum-equatorial current sustained by trade winds promoted low-latitude upwelling. Our set of simulations with the IPSL-CM5A2 model reveals that this paleogeographic setting favored proto-NADW upwelling at low latitudes, confining the AMOC to the Northern Hemisphere. Consequently, the role of southern westerly winds was limited, and the northward heat transport was weaker than in the modern ocean.
AB - Global ocean circulation regulates climate and has undergone significant changes over the Cenozoic. Today, the Atlantic Meridional Overturning Circulation (AMOC) is driven by North Atlantic Deep Water (NADW) formation and Southern Ocean upwelling. By contrast, during the middle Eocene to early Oligocene (48–28 Ma), a restricted Drake Passage was limiting the northern Ekman transport, while a circum-equatorial current sustained by trade winds promoted low-latitude upwelling. Our set of simulations with the IPSL-CM5A2 model reveals that this paleogeographic setting favored proto-NADW upwelling at low latitudes, confining the AMOC to the Northern Hemisphere. Consequently, the role of southern westerly winds was limited, and the northward heat transport was weaker than in the modern ocean.
U2 - 10.1029/2025GL119115
DO - 10.1029/2025GL119115
M3 - Article (Academic Journal)
SN - 0094-8276
VL - 53
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 2
M1 - e2025GL119115
ER -