The fight against global warming has a brand new weapon: whale poop.
Scientists from the Australian Antarctic Division have found that whale poop contains huge amounts of iron and when it is released into the waters, the iron-rich feces become food for phytoplankton. Phytoplankton absorbs carbon dioxide from the air, the algae is in turn eaten by Antarctic krill, and baleen whales eat the krill. Through this neat cycle, globe-warming CO2 is kept sequestered in the ocean.
Scientists have long known that iron is necessary to sustain phytoplankton growth in the oceans, which is why one geoengineering scheme calls for adding soluble iron to ocean waters to encourage the growth of carbon-trapping algae blooms. While environmentalists have fretted over the possible consequences of meddling with ocean chemistry that way, this new study on whale poop suggests an all-natural way to get the same carbon-trapping effect: Increase the number of whales in the ocean.