Reactive nitrogen cycling in the atmosphere and ocean

Globally, major quantities of reactive nitrogen (Nr) emitted from anthropogenic activities are ultimately deposited back to the Earth’s surface. However, our understanding of the interactions between Nr deposition and open ocean processes, and the role of the ocean in Nr production and atmospheric cycling remains limited. This review discusses our understanding of the impacts of Nr deposition on the open ocean, and the emissions of Nr from the ocean, placing particular emphasis on stable isotopes as a tool to investigate the surface ocean-lower atmosphere Nr cycle and its variations over time. Impacts of expected future climatic changes on ocean-atmosphere Nr cycling are also reviewed. The review ends with a summary of critical knowledge gaps and suggestions for future research directions.

Reference: Altieri, K. E., Fawcett, S. E., & Hastings, M. G. (2021). Reactive nitrogen cycling in the atmosphere and ocean. Annu. Rev. Earth Planet. Sci., 49, 523-550, https://doi.org/10.1146/annurev-earth-083120-052147.