Diagnosing the Atlantic Meridional Overturning Circulation in density space is critical in warmer climates

Oliveira Matos, Fernanda DI Alzira; Sidorenko, Dmitry; Shi, Xiaoxu; Ackermann, Lars; Pereira, Janini; Lohmann, Gerrit; Stepanek, Christian

doi:10.5194/os-21-2895-2025

Articles | Volume 21, issue 6

https://doi.org/10.5194/os-21-2895-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/os-21-2895-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 21, issue 6

Research article

|

13 Nov 2025

Research article |

| 13 Nov 2025

Diagnosing the Atlantic Meridional Overturning Circulation in density space is critical in warmer climates

Fernanda DI Alzira Oliveira Matos, Dmitry Sidorenko, Xiaoxu Shi, Lars Ackermann, Janini Pereira, Gerrit Lohmann, and Christian Stepanek

Data sets

Diagnosing the Atlantic Meridional Overturning Circulation in density space is critical under abrupt climate change - Model Output Part I Fernanda DI Alzira Oliveira Matos https://doi.org/10.5281/zenodo.15043857

Diagnosing the Atlantic Meridional Overturning Circulation in density space is critical under abrupt climate change - Model Output Part II Fernanda DI Alzira Oliveira Matos https://doi.org/10.5281/zenodo.15044678

Diagnosing the Atlantic Meridional Overturning Circulation in density space is critical under abrupt climate change - Model Output Part III Fernanda DI Alzira Oliveira Matos https://doi.org/10.5281/zenodo.15047024

Model code and software

Diagnosing the Atlantic Meridional Overturning Circulation in density space is critical under abrupt climate change - Scripts Fernanda DI Alzira Oliveira Matos https://doi.org/10.5281/zenodo.17395890

Short summary

The Atlantic Meridional Overturning Circulation (AMOC) is responsible for about 25 % of the poleward ocean heat transport. Currently, the AMOC strength is mostly calculated in depth space (z-AMOC). However, we argue that, in warmer climates, the AMOC should be calculated in density space (ρ-AMOC). We performed simulations with CO₂ forcing of 280 ppmv (PI) and 1120 ppmv of (4xCO₂) and find that ρ-AMOC provides more physical and meaningful information about the AMOC in warmer climates.