In violation, in the cold oceans, a very large object moves continuously, at about a few centimeters per second, in a path that has been moving for thousands of years. Dense, dark ocean currents operate continuously throughout the world, making up about 40 percent of the total volume of the deep oceans. They are the major transport belts of heat, air, oxygen, and nutrients around the world, and change climate and climate at global, regional, and local levels.
But things have changed, and these rivers seem to be shrinking. It’s no surprise that climate change can cause problems.
The tail bite is that slowing down this mechanism could actually accelerate climate change, while also reducing the productivity of the fisheries that many species—including humans—depend on for food.
In 1990, the Intergovernmental Panel on Climate Change (IPCC) released its first alarming report, the major link between the climate and the oceans was unknown, says climatologist and climate scientist Matthew England of the University of New South Wales in Sydney, Australia. . He said: “At that time what was happening was simple. “He had an atmosphere connected to a light ocean that had no changes.” It’s like a bathroom, he says. Oceans were known to absorb carbon dioxide and heat, but perhaps the connection between oceans and climate was explained in simpler terms.
Ocean science has come a long way since then, and has led to a more detailed understanding of the important role that global ocean belts play in climate change.
“Water moves, like the wind, in three-dimensional space; We have rivers that flow from left to right, and we have rivers that rise and fall,” said coastal biologist Ruth Reef, from Monash University in Melbourne, Australia.
The horizontal movement of water is due to drag from the wind. “When the wind blows across the ocean, it pulls the ocean together,” says Reef. Vertical motion is due to changes in the density of water. In trees, when salty sea water freezes in the ice water, the salinity of the remaining water increases, causing it to become less dense, and therefore sink.
This is the beginning of the conveyor belt engine. Trillions of tons of that cold, very cold water sinks to the deepest parts of the polar regions, and then moves deeper into the tropics. There the water rises and warms, and the warm currents—such as the Gulf Stream, which runs west to east across the North Atlantic and keeps winters in the United Kingdom—flow around the Pacific, Indian, and Atlantic oceans, releasing water. heat, oxygen, and nutrients and absorb carbon dioxide, before reaching the trees and the cycle begins again.
The Antarctic is the most powerful engine in this cycle, through the formation of Antarctic subsurface water. But this engine is in trouble.
“We show that the deep part of the water circulation is decreasing, and the amount of oxygen reaching the deep ocean is decreasing,” says Kathryn Gunn, an astrophysicist and climate scientist at the University of Southampton in the UK. He and his colleagues have been studying how the structure of Antarctic groundwater is changing. In a recently published study, which measured oxygen levels as a source of cold water circulation (because cold water carries more dissolved oxygen than heat), they looked at a part of the Antarctic shelf that crosses the Ross Sea and the Australian Antarctic Basin. . Their results show that the amount of cold, salty, low-oxygen water on the ocean floor decreased by 28 percent between 1994 and 2017.