The underappreciated role of anthropogenic sources in atmospheric soluble iron flux to the Southern Ocean

Autor: Mingxu Liu, Hitoshi Matsui, Douglas S. Hamilton, Kara D. Lamb, Sagar D. Rathod, Joshua P. Schwarz, Natalie M. Mahowald
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: npj Climate and Atmospheric Science, Vol 5, Iss 1, Pp 1-9 (2022)
Druh dokumentu: article
ISSN: 2397-3722
DOI: 10.1038/s41612-022-00250-w
Popis: Abstract The atmospheric deposition of soluble (bioaccessible) iron enhances ocean primary productivity and subsequent atmospheric CO2 sequestration in iron-limited ocean basins, especially the Southern Ocean. While anthropogenic sources have been recently suggested to be important in some northern hemisphere oceans, the role in the Southern Ocean remains ambiguous. By comparing multiple model simulations with the new aircraft observations for anthropogenic iron, we show that anthropogenic soluble iron deposition flux to the Southern Ocean could be underestimated by more than a factor of ten in previous modeling estimates. Our improved estimate for the anthropogenic iron budget enhances its contribution on the soluble iron deposition in the Southern Ocean from about 10% to 60%, implying a dominant role of anthropogenic sources. We predict that anthropogenic soluble iron deposition in the Southern Ocean is reduced substantially (30‒90%) by the year 2100, and plays a major role in the future evolution of atmospheric soluble iron inputs to the Southern Ocean.
Databáze: Directory of Open Access Journals