Work

Low-pressure storms drive nitrous oxide emissions in the Southern Ocean

Year: 2026

Type: article

Abstract: Nitrous oxide is a potent greenhouse gas and the primary ozone depletion agent of the 21 st century. Marine nitrous oxide emissions are difficult to constrain due to their sharp gradients and small scales of variability in space and time. In the Southern Ocean, where extratropical cyclones create conditions conducive to air-sea gas flux, shipboard sampling is unlikely to capture the full extent of nitrous oxide emissions due to the impracticality of sampling storms. Here, we propose that the Southern Ocean nitrous oxide source is almost double the magnitude of previous estimates. Machine learning-derived nitrous oxide observations from biogeochemical Argo floats reveal that low-pressure centers inside storms amplify air-sea disequilibria and create pulses of nitrous oxide to the atmosphere. Taking these low-pressure centers into account, rather than assuming a barometric pressure of 1 atmosphere, increases the net annual Southern Ocean nitrous oxide flux by 75%, explaining the discrepancy with previous estimates. Our results imply that the Southern Ocean plays a significant role in the global nitrous oxide cycle and may be a weaker net sink of greenhouse gases than previously thought.

Source: Nature Communications

DOI: 10.1038/s41467-026-68744-2

Authors: Colette L. Kelly, Bonnie X. Chang, Andrea F. Emmanuelli, Ellen R. Park, Alison M. Macdonald, David P. Nicholson

Institutions: Woods Hole Oceanographic Institution, University of Washington, Cooperative Institute for Climate, Ocean, & Ecosystem Studies, Massachusetts Institute of Technology

Language: English

Topic: Marine and coastal ecosystems

Subfield: Oceanography

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDGs: Climate action, Life below water

Open Access status: gold

Estimated APC paid: $6,990