Abstract

The biological carbon pump (BCP) plays a central role in regulating Earth’s climate by mediating the uptake and export of carbon from the surface ocean to the deep sea. Current global models estimate that between 5 and 12 gigatons of organic carbon are exported to the deep ocean each year. However, projections for the end of the century remain highly uncertain: models disagree on whether carbon export will increase or decrease across approximately 84% of the global ocean. This uncertainty highlights critical gaps in our understanding of the mechanisms that regulate the efficiency of the BCP . In this talk, I will present recent findings from my research group that investigate the mechanistic interactions shaping the biological carbon pump. We examine processes ranging from resource competition among plankton to the role of organismal vertical migration, integrating observations across multiple spatial and temporal scales. By combining laboratory incubations, field observations, and data from autonomous platforms, our work aims to identify the biological and ecological drivers that control carbon export and to improve the representation of these processes in predictive models. Together, these approaches provide new insights into the processes governing ocean carbon sequestration and help address whether we currently possess the mechanistic understanding needed to reliably predict the future of the biological carbon pump.