Articles | Volume 19, issue 18
Research article
 | Highlight paper
15 Sep 2022
Research article | Highlight paper |  | 15 Sep 2022

Observation-constrained estimates of the global ocean carbon sink from Earth system models

Jens Terhaar, Thomas L. Frölicher, and Fortunat Joos

Model code and software

Improved routines to model the ocean carbonate system: mocsy 2.0 ( J. C. Orr and J.-M. Epitalon

Accurate constraining the ocean carbon sink is of utmost importance to improve our understanding of the fate of anthropogenic carbon and to better project anthropogenic carbon uptake in the coming decades. This study combines the outcomes of a suite of earth-system models with three well-documented observations (sea surface salinity in the Southern Ocean, strength of Atlantic Overturning and Revelle factor) to reduce bias and uncertainty in the global ocean carbon sink. The results suggest that the ocean carbon sink is about 10% larger than estimated before. This has implications for the global carbon budget.
Short summary
Estimates of the ocean sink of anthropogenic carbon vary across various approaches. We show that the global ocean carbon sink can be estimated by three parameters, two of which approximate the ocean ventilation in the Southern Ocean and the North Atlantic, and one of which approximates the chemical capacity of the ocean to take up carbon. With observations of these parameters, we estimate that the global ocean carbon sink is 10 % larger than previously assumed, and we cut uncertainties in half.
Final-revised paper