Large areas of the planet’s oceans have become darker in the past two decades, according to researchers who fear this trend will have a severe impact on marine life all over the world.
Satellite data and numerical modeling revealed that more than the fifth global ocean had darkened between 2003 and 2022, which reduces the range of water that depends on sunlight and moonlight can flourish.
This effect is evident at a distance of 75 square meters (30 square meters) of the ocean, which is equivalent to the land area in Europe, Africa, China and North America combined, and the upper layer of water is disturbed as 90 % of marine species live.
Dr. Thomas Davis, the world of naval preservation at the University of Pleimouth, said the results were “a real cause of anxiety”, with severe repercussions on marine ecosystems, global fisheries, critical rotation of carbon and food in the ocean.
Most of the marine life flourishes in the oceanic areas of the world, which are the layers of the surface that allow adequate light through living organisms to exploit them. While sunlight can reach one kilometer below the waves, in practice, at least 200 meters a few meters.
This upper domain of water is the place called microscopic organisms that resemble plants. Living organisms support almost all seafood networks and generate approximately half of the planet oxygen. Many fish, marine mammals and other creatures hunt, nourish and multiply in the warmer water for light areas where food is more abundant.
Davis and his colleagues have based on satellite data and algorithm used to measure light in sea water to calculate the depths of light areas around the world. Darkness was affected by 21 % of the World Ocean in 20 years to 2022. In 9 % of the ocean, this led to the light areas of 50 meters, while the areas were 100 meters in 2.6 %. Details of this study appear in Global biology.
Darging the oceans when the light finds it difficult to penetrate the water. It is often seen along the coasts where the weight of cold nutrient water rises to the surface, and where the rain is sweeping the nutrients and sediments from the ground to water.
Drivers for darkening abroad are less clear, but heating and global changes are believed in peripheral currents. “It seems that the areas where there are major changes in the rotation of the ocean, or warming in the oceans led by climate change, grievance, like the southern ocean and even the Gulf course in Greenland,” said Davis.
The study found that about 10 % of the ocean, or 37 million square kilometers, has become lighter over the past twenty years. Just off the western coast of Ireland, for example, a very large area of the ocean shine, but it darkens it.
“The marine creatures use light for a whole set of purposes,” Davis said. ” “With the ocean shading, they must move the water column, and there is a lower space, all of which are crushed towards the surface.”
Professor Oliver Zellinski, director of the Leibniz Institute for the Baltic Sea Research in Germany, said that the grievance of the vast ocean regions was a “worrying trend.”
He said: “Such changes can disrupt marine food networks, change the distributions of species, and weaken the ocean’s ability to support biological diversity and climate regulation.” “The coastal seas, being closest to human activity, are especially weak, and their flexibility is crucial to both environmental health and human luxury.”
