Supplementary material from "Climate-driven variability of the Southern Ocean CO 2 sink ...

• Main Authors: Mayot, N., Le Quéré, C., Rödenbeck, C., Bernardello, R., Bopp, L., Djeutchouang, L. M., Gehlen, M., Gregor, L., Gruber, N., Hauck, J., Iida, Y., Ilyina, T., Keeling, R. F., Landschützer, P., Manning, A. C., Patara, L., Resplandy, L., Schwinger, J., Séférian, R., Watson, A. J., Wright, R. M., Zeng, J.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: The Royal Society 2023
• Subjects: Geochemistry; FOS Earth and related environmental sciences; Oceanography; Southern Ocean
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.6597304.v1; https://rs.figshare.com/collections/Supplementary_material_from_Climate-driven_variability_of_the_Southern_Ocean_CO_sub_2_sub_sink/6597304/1

The Southern Ocean is a major sink of atmospheric CO 2 , but the nature and magnitude of its variability remains uncertain and debated. Estimates based on observations suggest substantial variability which is not reproduced by process-based ocean models, with increasingly divergent estimates over the past decade. We examine potential constraints on the nature and magnitude of climate-driven variability of the Southern Ocean CO 2 sink from observation-based air–sea O 2 fluxes. On interannual timescales, the variability in the air–sea fluxes of CO 2 and O 2 estimated from observations is consistent across the two species and positively correlated with the variability simulated by ocean models. Our analysis suggests that variations in ocean ventilation related to the Southern Annular Mode are responsible for this interannual variability. On decadal timescales, the existence of significant variability in the air–sea CO 2 flux estimated from observations also tends to be supported by observation-based estimates ...