Researchers say oxygen is being produced on the ocean floor. The mining company funding them isn't happy
CBC
Oxygen is being produced on the ocean floor — seemingly by ancient lumps of metal — according to a new study. That discovery is putting the scientists behind it at odds with the Canada-based mining company that funded them.
"We were the worst critics of this paper for a long time," Andrew Sweetman of the Scottish Association for Marine Science, who led the study, said in a statement.
"For eight years I discarded the data showing oxygen production, thinking my sensors were faulty. Once we realized something may be going on, we tried to disprove it, but in the end we simply couldn't."
The discovery has profound implications for our understanding of the deep ocean and its ecology. Scientists say the organisms that inhabit those ocean depths — which are also a mystery — may depend on oxygen from this newly discovered source.
But the study, published in Nature Geoscience, was funded in part by The Metals Company, a Vancouver-based mining firm that has spent years arguing that mining in the deep ocean has a relatively low environmental impact, and is a better way to extract valuable minerals needed in green energy technology.
The company is now disputing the study's findings, which could throw a wrench in its and others' plans to mine the seabed.
Scientists from Europe and the U.S. collected and examined metallic, plum-sized lumps called nodules from the depths of around four kilometres of the Pacific Ocean's floor, finding that they appeared to be creating oxygen out of seawater through a chemical reaction. The source of energy behind the reaction, along with several other details about how it is occurring, remains a mystery.
The nodules are believed to have formed over millions of years. They contain essential minerals that can power the transition to green energy, such as cobalt and lithium that are needed in technologies like electric-vehicle batteries, and companies want to extract them.
The study says the nodules carry an electric charge that could be splitting water molecules into this "dark oxygen," through a process called seawater electrolysis.
If they are indeed a significant source of oxygen for deep-sea creatures, extracting them could damage or destroy those ecosystems.
TMC has released a statement calling the dark oxygen research "flawed," raising concerns about how the nodules were collected, and cited a study conducted by different researchers in a similar area that had contradicting results.
It said it is planning a more detailed scientific rebuttal to be published in the coming weeks, involving its own scientists and outside experts.
The company focuses on mining a part of the Clarion-Clipperton Zone, which is in the Pacific between Hawaii and Mexico, partnering with the island nation of Nauru to do so. It has supported other research on the ocean floor to demonstrate the impacts of mining it.
"We've never said that picking up these rocks and turning them into battery metals will have zero impact," said Gerard Barron, the chief executive officer of The Metals Company, in an interview.
