A team of researchers led by scientists at Princeton University and ETH Zurich have confirmed that dust brought iron to the Subantarctic zone in the northern part of the Southern Ocean. This region lies in the path of the winds that blow off South America, South Africa and Australia. During the last ice age, an increase in the supply of dust to the Subantarctic region fertilized the ocean, stimulating marine productivity and causing nitrogen to be drawn down to low levels. The associated increase in the efficiency of carbon sequestration into the deep ocean can explain part of the atmospheric CO2 decrease observed during the last ice age. The image shows the emission and transport of dust and other important aerosols to the Southern Ocean on Dec. 30, 2006. Dust is represented with orange to red colors, sea salt with blue, organic and black carbon with green to yellow, and sulfates with ash brown to white. In the image, a plume of dust has been emitted from southern South America and is being transported eastward over the Subantarctic Atlantic Ocean. (Image courtesy of William Putnam and Arlindo da Silva, NASA/Goddard Space Flight Center)