Geoengineering, or hacking Earth’s climate system to cool the planet, is a controversial field that promises to either save our collective asses or bring on the apocalypse. Now, scientists have discovered a major problem with one popular geoengineering scheme that entails dumping a bunch of iron into the ocean to soak up carbon dioxide. Basically, the plan is not supported by the geologic record.
Proponents of “iron fertilization” say that spiking the Pacific Ocean with this critical nutrient will turbo-charge algae, prompting them to draw more carbon out of the atmosphere. This carbon will eventually sink into the deep ocean and become sequestered. While the concept has seen little practical success, and has created at least one international scandal, the dream of cooling our planet with fertilizer while cashing in on carbon credits never seems to die.