@article{discovery10184562, title = {Surface Ocean Cooling in the Eocene North Atlantic Coincides With Declining Atmospheric CO2}, year = {2023}, number = {24}, journal = {Geophysical Research Letters}, note = {This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third-party material in this article are included in the Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/}, publisher = {American Geophysical Union (AGU)}, month = {December}, volume = {50}, author = {Inglis, Gordon N and Bhatia, Rehemat and Evans, David and Zhu, Jiang and M{\"u}ller, Wolfgang and Mattey, David and Thornalley, David JR and Stockey, Richard G and Wade, Bridget S}, url = {http://dx.doi.org/10.1029/2023gl105448}, abstract = {The Eocene (56-34 million years ago) is characterized by declining sea surface temperatures (SSTs) in the low latitudes ({$\sim$}4oC) and high southern latitudes ({$\sim$}8-11oC), in accord with decreasing CO2 estimates. However, in the mid-to-high northern latitudes there is no evidence for surface water cooling, suggesting thermal decoupling between northern and southern hemispheres and additional non-CO2 controls. To explore this further, we present a multi-proxy (Mg/Ca, {\ensuremath{\delta}}18O, TEX86) SST record from Bass River in the western North Atlantic. Our compiled multi-proxy SST record confirms a net decline in SSTs ({$\sim$}4oC) between the early Eocene Climatic Optimum (53.3-49.1�Ma) and mid-Eocene ({$\sim$}44-41�Ma), supporting declining atmospheric CO2 as the primary mechanism of Eocene cooling. However, from the mid-Eocene onwards, east-west North Atlantic temperature gradients exhibit different trends, which we attribute to incursion of warmer waters into the eastern North Atlantic and inception of Northern Component Water across the early-middle Eocene transition.}, keywords = {Cenozoic temperature, multi-proxy, North Atlantic eocene, foraminifera} }