Oceans as climate allies

Since their formation, the oceans have played a leading role in Earth’s carbon cycle. The chemistry of water has enabled oceans to soak up and store vast amounts of carbon dioxide for millennia. This naturally occurring process makes the oceans targets for people studying carbon dioxide removal; tweaking the water chemistry may boost the ocean’s carbon-sucking abilities. But scientists in the nascent field of marine carbon dioxide removal argue that much more research—in the laboratory and the field—is vital before considering full-scale deployment of the approach. If you had asked him a decade ago, marine biogeochemist Kai Shulz of Southern Cross University would have distanced himself from work probing how the oceans could be engineered to absorb more carbon dioxide. “I thought it would be kind of ridiculous to have a billion-dollar industry that is emitting CO 2 and then create another billion-dollar industry that takes the CO 2 out