I know that introducing iron in an iron depleted area does cause a phytoplankton bloom, but from what I have read, even with John Martin's "Give me a half a tanker of iron and I will give you another ice age" quote as being self-promoting bunk. There is some legitimate science to it, but decreasing CO2 (on a human scale) with iron is more of a delusional solution for people not to address the real issues of industrialization effects.
Also, isn't there also a phytoplankton predator boom that happens along with the iron dosing, feeding off of the phytoplankton... which produces CO2 and reduces the effect?
LOHAFEX is not an isolated case. Several environmentalists are alarmed to learn last week that another ocean fertilization scheme is being developed.  Now this is urea, a fertilizer rich in nitrogen, to attempt to throw in March at the Tasman Sea (between Australia and New Zealand) . Under the auspices of the Ocean Technology Group at the University of Sydney, led by Ian S. F. Jones, funders of the project hope the green light from the government of Australia to produce urea in international waters. Under the protection of a "research institute," Professor Jones is also the man in front of Ocean Nourishment Corporation, and is well known for his interest in the potential gains from such projects.  It appears that the caution that shaped the discussions in the CBD for less than one year are throwing overboard and civil society need to work hard to maintain the moratorium and to ensure stronger.
Well forgive me if I came out to harsh, but the (over the top) claims of individuals have garnered attention, but also incorrect public attention and understanding over some issues that damage other researchers and other studies. I have no problem with drawing attention to a research area or phenomenon, but the tanker-iceage is a bit PT Barnum for me. I support research, even ocean nourishment research that will not have a long term affect, but I think there is "research" that is just trying to fit a pre-existing ideology and the "results" will be forced to fit within that paradigm.
"It has never been a permit to investigate the ocean
The president of Planktos, Russ George, not the opposition that is finding its proposed fertilizing the ocean with iron to observe their possible contribution in the fight against global warming. "The coast of the Canary Islands receives millions of tons of iron from the Sahara in a natural way, there are phytoplankton blooms continuously," he argues. According to George, his project should not alarm anyone: "Some organizations say they are going to throw thousands of tons of iron to the ocean, but it is ridiculous, the Weatherbird II is a small boat and let's just dump tens of tonnes in a region the millions who come to them naturally. " The oceanographer of San Francisco does not confirm the exact amount of ore dump at sea, because, says it is first necessary to study the ecosystem of the area. "This is science," he said.
The arrival of the vessel at this time Planktos is not coincidental. In winter there is a smaller number of natural phytoplankton blooms, which, according to George, is a good moment to provoke a 'bloom' artificial.
As for the lack of authorization to dump iron in international waters, the president of Planktos is emphatic: "Never in the history of oceanography has been necessary to ask permission to investigate the ocean."