For centuries, Earth’s oceans have been blue. However, research states that oceans will gradually turn green again. By again, I mean, once upon a time the oceans used to be green; now, they are blue and will return to green again, according to scientists and experts. According to New Scientist, the evolution of the cyanobacteria that supplied the atmosphere with livable amounts of oxygen was likely influenced by Earth’s green phase, which lasted from approximately 3 billion to 600 million years ago.
Changes in ocean colour are linked to climate change, transformations that happen in the marine ecosystems and just changes in general that we might not mention in this article today. The concept of oceans changing colour does make us question a lot about the behavioural patterns of the earth since the Big Bang. If it is not about the universe and space, it is about the land and oceans changing colour over time.
Why are the oceans on Earth getting greener?
Before I explain why the oceans are turning green, let me give you a brief background. Since the history of time, Earth’s oceans have been green, greener than they are today, although today they are more of a cyan, turquoise blue colour. An article by Popular Mechanics even expressed that if aliens were to come during that time, they would identify it as green.
Now this is why the oceans are turning green soon. A little but potent force called phytoplankton is at the centre of this change. Due to their vital roles in the carbon cycle, oxygen production, and marine food chains, these microscopic marine organisms account for a large portion of the ocean’s productivity. The chlorophyll they possess turns the water green when their populations increase significantly, causing the dramatic colour shifts that satellites are currently witnessing.
However, scientists believe that it could potentially not be the only or exact reason for the oceans turning green again. One of the key factors contributing is climate change. There are also marine ecosystem changes transpiring, with waters getting warmer, leading to this colour change. Although it is not yet a thing, other regions are showing signs of ocean or water distress that is changing colour rapidly.
A retrospection: Were the waters ever green?
Yes, there was a time when the waters were green. This was before oxygen levels increased, when the oceans were dominated by primitive microorganisms and green-hued waters, long before complex marine life flourished. However, it looks like Earth wants to send a message and bring back the ancient originality. Human activity and climate change have triggered this move.
Additionally, the colour changes are said to be happening faster than expected and the pace at which it is happening raises concern, especially for marine biodiversity. It looks like there is an imbalance within the oceans. Unfortunately, if this continues, it will affect the entire food chain within the waters, affecting humanity too.
Where do we stand? Should we be worried?
Prior to the blue oceans, green oceans meant that the waters were in good condition and thriving. Now, today, if they are turning green, it does not mean they are going back to healthy conditions; rather, it is a trigger due to human activity and climate change as mentioned above. Monitoring and deep studies are important to comprehend what measures can be taken to stop this from affecting the marine ecosystem.
The thing is, though, we do not know if this is a good change or a bad change. What if the earth is recovering itself by trying to get rid of the contamination, yet we are thinking perhaps it is a bad thing? Either way, experts should still find out what could be the reason. Popular Mechanics states that 56% of the world’s oceans have already turned green in the last 20 years, according to follow-up research conducted in 2023.