Scientists may have found a new way to slow the progression of global warming, but at first, this method sounds a bit out there. It involves dumping iron sulphate into the oceans, which will then spur the growth of carbon-trapping algae. The algae will then remove carbon dioxide from the atmosphere through photosynthesis, and once the algae dies, it will fall to the ocean floor, taking the trapped carbon with it.
That’s according to a new report issued this week by the European Iron Fertilization Experiment (EIFEX). In 2004, a team of EIFEX researchers fertilized 167 square kilometers of the Southern Ocean with the iron sulphate, and watched for the next 37 days as phytoplankton flourished and died. What they found is somewhat exciting: the team says that at least half of the bloom sank to depths below 1,000 meters, taking the carbon it had captured with it. The carbon will likely stay trapped down there for centuries to come, whereas if the bloom had died and settled near the surface, all of that captured carbon would have had a chance at returning to the atmosphere.
So, fertilizing the ocean with iron sulphate may help slow global warming, but this discovery does not come without controversy. Some scientists are concerned about the long-term effects of continuously adding iron in the sea, saying that doing so could have adverse effects on marine ecosystems. Causing such a spike in algae growth could deplete the oxygen level in the water column, they say, or lead to toxic algae growth.
It sounds like this is just one of those things that needs to be researched more before scientists can make the call. The results of the study are promising, but scientists say that they’re “nowhere near” offering iron fertilization as a solution to global warming. Stay tuned, as further research could show that climate scientists have something big on their hands.