Iron Fertilization - Experiments

Experiments

Martin hypothesized that increasing phytoplankton photosynthesis could slow or even reverse global warming by sequestering enormous volumes of CO₂ in the sea. He died shortly thereafter during preparations for Ironex I, a proof of concept research voyage, which was successfully carried out near the Galapagos Islands in 1993 by his colleagues at Moss Landing Marine Laboratories. Since then 9 international ocean studies have examined the fertilization effects of iron:

• Ironex II, 1995
• SOIREE (Southern Ocean Iron Release Experiment), 1999
• EisenEx (Iron Experiment), 2000
• SEEDS (Subarctic Pacific Iron Experiment for Ecosystem Dynamics Study), 2001
• SOFeX (Southern Ocean Iron Experiments - North & South), 2002
• SERIES (Subarctic Ecosystem Response to Iron Enrichment Study), 2002
• SEEDS-II, 2004
• EIFEX (European Iron Fertilization Experiment), 2004
• CROZEX (CROZet natural iron bloom and Export experiment), 2005
• LOHAFEX (Indian and German Iron Fertilization Experiment), 2009 Despite widespread opposition to LOHAFEX, on 26 January 2009 the German Federal Ministry of Education and Research (BMBF) gave clearance for this fertilization experiment to commence. The experiment was carried out in waters low in silicic acid which is likely to affect the efficacy of carbon sequestration. A 900 square kilometers (350 sq mi) portion of the southwest Atlantic Ocean was fertilized with iron sulfate. A large phytoplankton bloom was triggered, however this bloom did not contain diatoms because the fertilized location was already depleted in silicic acid, an essential nutrient for diatom growth. In the absence of diatoms, a relatively small amount of carbon was sequestered, because other phytoplankton are vulnerable to predation by zooplankton and do not sink rapidly upon death. These poor sequestration results have caused some to suggest that ocean iron fertilization is not an effective carbon mitigation strategy in general. However, prior ocean fertilization experiments in high silica locations have observed much higher carbon sequestration rates because of diatom growth. LOHAFEX has just confirmed that the carbon sequestration potential depends strongly upon careful choice of location.
• One pilot project planned by Planktos, a U.S. company, was cancelled in 2008 for lack of funding. The company blamed environmental organizations for the failure.
• In 2012 Russ George, founder of Planktos, and collaborators conducted an iron fertilization experiment dumping 100 tonnes of iron sulphate into the Pacific Ocean from a fishing boat in an eddy 200 nautical miles west of the islands of Haida Gwaii which resulted in increased algae growth over 10,000 square miles. Critics allege George's actions violated the United Nations Convention on Biological Diversity (CBD) and the London convention on the dumping of wastes at sea which according to them contain moratoriums on geoengineering experiments.
• A successful experiment conducted in 2004 in a mesoscale ocean eddy in the South Atlantic resulted in a bloom of diatoms a large portion of which died and sank to the ocean floor when iron fertilization was discontinued. In contrast to the LOHAFEX experiment, also conducted in a mesoscale eddy, the ocean in the selected area contained enough dissolved silicon ions for the diatoms to flourish.