Full article: Iron Fertilization
Iron fertilization is a facet of geoengineering, which purposefully manipulates the Earth's climate system, typically in aspects of the carbon cycle or radiative forcing. Of current geoengineering interest is the possibility of accelerating the biological pump to increase export of carbon from the surface ocean. This increased export could theoretically remove excess carbon dioxide from the atmosphere for storage in the deep ocean.  Ongoing investigations regarding artificial fertilization exist. Due to the scale of the ocean and the fast response times of heterotrophic communities to increases in primary production, it is difficult to determine whether limiting-nutrient fertilization results in an increase in carbon export.  However, the majority of the community does not believe this is a reasonable or viable approach.