The concentration of carbon dioxide (CO2) in Earth’s atmosphere has risen by ~38% since the start of the industrial era as a result of fossil fuel burning and land use changes; if current trends continue, it is projected to increase further by at least a factor of 2 by 2100. About a quarter of the CO2 emitted through human activities has been absorbed by the ocean. On page 676 of this issue, Shi et al. show that the resulting acidification of ocean surface waters may decrease the biological availability of iron, which could in turn reduce the ability of the ocean to take up CO2.
Sunda, W. G., 2010. Iron and the carbon pump. Science 327(5966): 654-655. Article (subscription required).
