Iron Fertilization Might Be Ineffective Against Global Warming, Fossil Study Shows
http://www.huffingtonpost.com/2014/03/21/iron-fertilization-global-warming-fossils_n_5006300.html
During Earth's last ice age, iron dust dumped into the ocean fertilized the garden of the sea, feeding a plankton bloom that soaked up carbon dioxide from the air, a new study confirms.
But the results deal a blow to some geoengineering schemes that claim that people may be able use iron fertilization to slow global warming. The planet's natural experiment shows it would take at least a thousand years to lower carbon dioxide levels by 40 parts per million the amount of the drop during the ice age.
Meanwhile, carbon dioxide is now increasing by 2 parts per million yearly, so in about 20 years human emissions could add another 40 parts per million of carbon dioxide to the atmosphere. Levels currently hover around 400 parts per million.
"Even if we could reproduce what works in the natural world, it's not going to solve the carbon dioxide problem," said Alfredo Martínez-García, a climate scientist at ETH Zurich in Switzerland and author of the study, published today (March 20) in the journal Science.