Scientists indicated that the Earth's atmosphere could undergo a drastic transition, reverting to a state comparable to that before the Great Oxidation Event (GOE) roughly 2.4 billion years ago. This event, which resulted in a huge increase in atmospheric oxygen, radically altered our planet's ecology and allowed the survival of many species, including humans.
When Earth formed approximately 4.5 billion years ago, its condition was too different. Water vapour, methane, and carbon dioxide dominated the Earth's atmosphere. Lately, researchers have predicted that the Earth's atmosphere will return to its first form, i.e. low in oxygen.
A recent study issued in Nature explained the scenario and when it will happen. However, such a scenario is unlikely to occur for billions of years, stressing that it will transform very quickly when the change occurs.
Earth to return to its previous state
According to scientists, the change will return Earth to the state it was before, called the Great Oxidation Event (GOE) almost 2.4 billion years ago. The study has been discussed as scientists attempt to discover habitable planets outside the Solar System. According to the report, atmospheric oxygen is unlikely to be a permanent component of all habitable worlds.
While in conversation with New Scientist, Chris Reinhard from Georgia Institute of Technology said, "The oxygen level drop is very, very extreme. We are talking about a million times less oxygen than today."
Scientist created Earth's model
According to the Scientists who predicted the doomsday scenario, "The model projects that a deoxygenation of the atmosphere, with atmospheric O2 dropping sharply to levels reminiscent of the Archaean Earth, will most probably be triggered before the inception of moist greenhouse conditions in Earth's climate system and before the extensive loss of surface water from the atmosphere."
Researchers created Earth's detailed models of the atmosphere, and shifts in the Sun's brightness and carbon dioxide levels drops were studied. Less carbon dioxide signifies fewer photosynthesising organisms, such as plants, eventually results in less oxygen.