Solving the Mysteries of ‘Dark’ Oxygen in the Deep Ocean

'Dark' Oxygen in the Deep Ocean
Image: Newsweek

In a groundbreaking discovery that challenges long-held scientific beliefs, researchers have identified a phenomenon termed ‘dark’ oxygen production occurring over 13,000 feet below sea level in the Pacific Ocean.

This revelation not only alters our understanding of oxygen generation in marine environments but also offers potential insights into the origins of life on Earth.

Ocean scientist Andrew Sweetman first encountered signs of this phenomenon in 2013 while conducting research in the Clarion-Clipperton Zone, a vast area of the deep sea between Hawaii and Mexico.

Initial readings from monitoring equipment indicated oxygen production at the seafloor in complete darkness, contradicting established scientific knowledge that oxygen production requires sunlight.

Sweetman initially dismissed these readings, believing the sensors were malfunctioning. However, repeated verification by the sensor manufacturer confirmed their accuracy.

Further investigation revealed that metallic nodules scattered across the seabed were responsible for this unexpected oxygen production. These nodules, composed of metals like lithium, cobalt, and copper, act similarly to batteries.

When these metals come into contact with seawater, they create electric currents that split water molecules (H2O) into hydrogen and oxygen-a process known as electrolysis.

This discovery was substantiated through laboratory experiments measuring the voltages on the surface of these nodules, which were found to be comparable to those of a standard AA battery.

The presence of these metallic nodules, capable of producing oxygen without sunlight, has significant implications for deep-sea ecosystems.

Traditionally, it was believed that oxygen in the deep ocean originated from surface photosynthesis and was transported downward. The discovery of an independent oxygen source suggests that these nodules may support marine life in previously unrecognized ways.

However, this revelation comes at a time when deep-sea mining is gaining momentum. Mining companies are eager to extract these valuable metallic nodules for use in batteries and other technologies.

This raises concerns among marine scientists about the potential ecological impact. The destruction of these nodules through mining could disrupt the newly discovered oxygen production process, potentially harming the deep-sea organisms that rely on it.

More than 800 marine scientists from 44 countries have signed a petition calling for a moratorium on deep-sea mining, citing the need to better understand these ecosystems before potentially irreversible damage is done.

The US National Oceanic and Atmospheric Administration (NOAA) has also warned of the risks associated with seabed mining, highlighting the potential destruction of life and habitat in mined areas.

Professor Sweetman and his colleagues emphasize the importance of further research to explore the extent of ‘dark’ oxygen production and its ecological implications.

Understanding this process could not only protect deep-sea environments but also provide valuable insights into the origins of life on Earth. The notion that similar electrochemical processes could occur on other planets and moons opens new avenues for the search for extraterrestrial life.

The discovery of ‘dark’ oxygen production in the deep ocean challenges existing scientific paradigms and underscores the complexity of marine ecosystems.

As researchers delve deeper into this phenomenon, it is crucial to balance technological advancement with environmental stewardship. Protecting these newly discovered processes may hold the key to preserving the deep ocean’s biodiversity and unlocking the mysteries of life’s origins both on Earth and beyond.

Victoria Gill, a science correspondent for BBC News, noted, “Until this discovery, it was believed that oxygen could not be produced without sunlight. This challenges our fundamental understanding of marine biology and the deep-sea environment.”

Furthermore, Professor Sweetman remarked, “We need to explore it in greater detail and we need to use this information and the data we gather in future if we are going to go into the deep ocean and mine it in the most environmentally friendly way possible.”