What does the discovery of deep sea oxygen mean?
1st October 2024
Authored by Weirdsmiths
For the longest time, it has been thought and told that the majority, if not all, oxygen on our planet has originated from plant-life photosynthesising. We even knew that around half of the total oxygen produced came from the ocean, presumably from the marine plants despite a lessened level of sunlight; however, this becomes questionable at levels of no sunlight.
A recent discovery has found that at depths of 5km, where there is no sunlight at all, oxygen is still being produced; but, not from plants. Scientists have found that “dark oxygen” is actually being produced by naturally occuring metal “nodules”, splitting seawater into individual hydrogen and oxygen atoms.
The discovery
Professor Andrew Sweetman, from the Scottish Association for Marine Science, told BBC News that he had originally spotted this phenomenon back in 2013, but initially ignored it because he had been taught “you only get oxygen through photosynthesis”. He did, however, later realise that he’d potentially been ignoring a huge discovery, and decided to carry out further research in the deep sea between Hawaii and Mexico – focusing a segment of the seafloor that was rich in these metallic nodules.
The metallic nodules form over millions of years and are made up of metals like copper, cobalt manganese, nickel and lithium that are dissolved within the ocean. These small metals cling onto fragments of shells, wood or other debris and form nodules. These modules then complete a process called electrolysis to split the H2O molecules into separate components, but how exactly they are doing it is not quite known. We know there must be an electric current for electrolysis, but it isn’t known where it’s coming from, whether it’s continuous, or even the volume produced.
Problems and issues
One of the largest issues this discovery presents is with the preservation and further study of it, with a huge interest in the metallic modules already being underway with several mining companies. The metals found in these nodules are considered to be a new-class of precious metals due to their use in battery manufacturing, so these companies are developing new ways to collect them and bring them to the surface.
With further tests away from the seabed, it could be deduced that it is exactly the properties within the metal that make them ideal for batteries that help to produce the oxygen. Professor Sweetman explain that if you put a battery in seawater it starts to fizz, simply because it generates an electric current that begins the electrolysis process.
Professor Sweetman and his team, as well as other scientists, state that this discovery raises even more concerns about the risks of deep-sea mining, something that was already controversial, stating that the oxygen produced by these nodules may support life already. Sweetman even toys with the idea that the electrolysis within these modules could have been the initial spark of life on Earth so long ago, leading to further questions entirely.
Before this development, there were already wide discussions about the fragility and necessity of the deep sea, with over 800 marine scientists from 44 countries signing a petition that highlights the risks of exploiting this delicate resource.
How has it been received?
While the scientific community are loving the new discovery and the questions it poses, there has naturally been backlash from those who think we should be using the resource. Patrick Downes of the Metals Company, one of the deep sea mining companies interested in these nodules, says the findings are the result of oxygen contamination from outside sources. The Metals Company partly funded Sweetman’s research and state that they will soon produce a paper disputing the theory put forward by Sweetman and his team.
As with most marine scientists, the US National Oceanic and Atmospheric Administration (NOAA) has warned that the mining of these nodules could pose serious risk, including the “destruction of life and the seabed habitat in the mined areas”.
As time goes on, we are consistently discovering new species of life within unexplored areas of the deep ocean, and we truly don’t know if taking this resource will effect the life that we have discovered, but, more importantly, the life we have yet to learn more about. The areas of the seabed containing these nodules are vast and cover a large chunk of our planet, and people like Professor Murray Roberts, of the University of Edinburgh, believe that it would be “crazy to press ahead with deep-sea mining knowing they may be a significant source of oxygen production.”
Summary
As with most scientific discoveries there will always be two sides of the coin, but how we move forward is going to be crucial to this specific revelation. The gathering of resources for electric vehicles, and other “green” products, has been a hotly debated topic for a long time, and this discovery will only add fuel to the fire. As to the implications on our climate and global warming, it is yet to be seen, but the risks of destroying a source of oxygen when we are already struggling with things like deforestation and pollution seems too high.
With extensive theories about how these metallic nodules may exist on other planets, the implications from finding out oxygen can be produced without light and many other questions on the back of all of this, we’re excited to see where the discovery of dark oxygen goes.
Thanks for reading!
We hope you enjoyed reading this as much as we did writing it. If you liked what you read, learned something new, or think someone else will love this too, please share with your friends and family!
