Link: http://www.newscientist.com/article/dn16390-climate-fix-ship-sets-sail-with-plan-to-dump-iron-.html

I dunno if you remember - but a ways back there was a big argument about an attempt to dump iron powder into the ocean ( plankton feeds on it ) and this would then in turn create a bloom which would then in turn take Carbon out of the atmosphere.

Well, despite it still being a hugely debated idea the ship has set sail. So, I guess we will all get to see how this works out.