Iron fertilisation as a climate geoengineering option
In an Atmospheric Environment New Directions article, Matthew Woodhouse has used GLOMAP to quantify the impact of iron fertilisation of the Southern Ocean on cloud condensation nuclei. Previous work has suggested that iron fertilisation of a patch of the Southern Ocean would lead to greatly increased dimethyl sulfide (DMS) emissions, resulting in substantial perturbations to natural CCN (Wingenter et al., 2007). We calculated the impact of such enhanced emissions on CCN in GLOMAP. The model shows very nicely how CCN are produced thousands of km downwind of the DMS patch. However, the net effect on Southern Ocean CCN is much less than previously estimated, suggesting that iron fertilisation may not be an efficient way of geoengineering the climate after all.
New Directions: The impact of oceanic iron fertilisation on cloud condensation nuclei, Matthew T. Woodhouse, Graham W. Mann, Kenneth S. Carslaw, and Olivier Boucher, Atmospheric Environment, Volume 42, Issue 22, July 2008, Pages 5728–5730.