A study of marine sediments in the South Pacific and South Atlantic finds that during glacial periods the proportion of bioavailable iron in glacially-produced dust transported to the Southern Ocean, which supports phytoplankton growth and subsequent removal of carbon dioxide in the form of organic matter, is 25-45% of iron in dust, whereas in interglacial periods the proportion is around 5-10%, suggesting that glacial dust can serve as a positive climate feedback by removing atmospheric carbon dioxide during glacial periods.
Article #18-09755: "Highly bioavailable dust-borne iron delivered to the Southern Ocean during glacial periods," by Elizabeth M. Shoenfelt, Gisela Winckler, Frank Lamy, Robert F. Anderson, and Benjamin C. Bostick.
MEDIA CONTACT: Elizabeth M. Shoenfelt, Columbia University's Lamont-Doherty Earth Observatory, Palisades, NY; tel: 845-365-8328; e-mail: shoen@ldeo.columbia.edu
###
Proceedings of the National Academy of Sciences