The buildup of CO2 in the atmosphere resulting from the burning of fossil fuels is regarded as a major contributor to global warming. Diatoms and other microscopic algae in the oceans counter this buildup by using large quantities of atmospheric CO2 in photosynthesis, which requires small quantities of iron. Experts suspect that a shortage of iron may limit algal growth in the oceans. Some scientists have suggested that one way to reduce CO2 buildup might be to fertilize the oceans with iron. The iron would stimulate algal growth and thus the removal of more CO2 from the air. A single supertanker of iron dust, spread over a wide enough area, might reduce the atmospheric CO2 level significantly. Do you think this approach would be worth a try? Why or why not?