Scientists have made an exciting discovery in one of the most remote parts of the ocean. In Pacific’s Clarion-Clipperton Zone or CCZ, oxygen has formed in a way we never thought possible, without any sunlight or plant life involved. This oxygen, called “dark oxygen,” is not made by plants or algae but through a chemical reaction involving metals.
Most of us learned in school that ocean oxygen is generated by sunlight-dependent photosynthesis, a process done by plants and algae. However, scientists measuring oxygen levels in the CCZ found a mysterious oxygen source around strange rocks known as polymetallic nodules. These nodules, containing metals like manganese and cobalt, act like small natural batteries. When they interact with the saltwater, they produce small electrical currents, which cause oxygen and hydrogen to form from water, similar to electrolysis.
The deep-sea creatures that survive in these dark, high-pressure areas may have depended on these nodules for habitat and possibly even oxygen all these years. Scientists think dark oxygen production suggests that life can emerge and thrive in environments with lower oxygen levels than previously assumed. They even speculate that dark oxygen could sustain life on other water-rich worlds, such as Jupiter’s moon Europa.
Polymetallic nodules are not only interesting for their natural “rock-battery” properties, but they’re also valuable for modern technology. The metals they contain, cobalt, nickel, copper, and manganese, can be critical for batteries, smartphones, and wind turbines. However, extracting these nodules could disrupt dark oxygen production and put deep-sea ecosystems at risk. Mining the ocean floor would likely destroy habitats and reduce oxygen.
Scientists and environmental groups are urging caution. Over 800 researchers have signed petitions against deep-sea mining, and some countries have pushed for a ban until we fully understand the impact. The race for new resources must be balanced with preserving these unique ecosystems.
Dark oxygen reminds us how much is left to learn about our planet. Discoveries like this challenge long-held ideas about how and where life can thrive. By studying dark oxygen, scientists hope to unlock Earth’s secrets and find clues to life on other planets. As the world considers deep-sea mining for valuable metals, this discovery highlights the need for thoughtful approaches to resource extraction that will not harm ocean habitats relying on dark oxygen.
Works Cited
Smithsonian Magazine, “Scientists Discover ‘Dark Oxygen’ on the Ocean Floor Generated—Surprisingly—by Lumps of Metal.”
ECOticias, “Dark Oxygen, Discovered Under the Sea for the First Time in History: It’s Not Good News at All.”
BBC News, “Polymetallic Nodules Generate Oxygen, Bringing a New Perspective to Marine Life.”