According to BBC News, scientists aboard the German research ship the Polarstern have begun dumping iron particles into an area of the Scotia Sea east of Argentina in an ocean fertilization experiment. The expedition had been suspended by the German government because of concerns that it violated the UN’s Convention On Biological Diversity. But with the expedition reauthorized by the German government the experiment is being carried out. The BBC article says that 6 tons of iron sulfate are being dumped into the ocean, although it has been reported that the ship set out with 20 tons.
This ocean fertilization experiment is taking place at a time when a new published research report described in an article posted at Yahoo News provides both good and bad news for the idea of dumping iron into the ocean to stimulate phytoplankton blooms as a way of countering global warming. The good news is that the research team, which was led by Raymond Pollard of the National Oceanography Centre of Southhampton in England, found that plankton were much more abundant in ocean water high in iron content than in ocean water that was iron-poor, suggesting that adding iron will produce plankton blooms. The bad news was that the research team found that only about 10% of the phytoplankton actually wind up on the bottom of the ocean. The remaining 90% don’t sink all way down and eventually, perhaps after decades or even longer, the carbon dioxide that the plankton had taken up from the atmosphere through photosynthesis gets back up to the surface. The smaller the percentage of carbon dioxide that gets permanently stored at the ocean bottom using this scheme the larger area of ocean that would be needed to have a significant affect on global warming, thereby maximizing costs and perhaps most importantly, risks.