Ocean currents in the Atlantic could slow by the end of the century, research suggests

The system of ocean currents that regulates the climate of part of the planet could collapse sooner than expected, according to a new analysis.

The last time there was a major slowdown in the powerful network of ocean currents that shapes the climate around the North Atlantic, it seems to have plunged Europe into deep cold for more than a millennium.

That was about 12,800 years ago, when few people were around to experience it. But in recent decades, human-induced warming could once again slow the currents, and scientists have been working to determine if and when they might experience another significant weakening, which would have ripple effects on weather patterns over part of the globe. century.

< p class="css-at9mc1 evys1bk0">It was a surprise even to the researchers that their analysis showed a potential collapse to come so soon, one of them, Susanne Ditlevsen, professor of statistics at the University of Copenhagen, said in an interview. Climatologists generally agree that the Atlantic circulation will decrease during this century, but there is no consensus on whether it will stop before 2100.

So it was also a surprise, said Dr. Ditlevsen, that she and her co-author were able to pinpoint the timing of the collapse. Scientists are bound to continue to study and debate the issue, but Dr Ditlevsen said the new findings are reason enough not to consider a shutdown an abstract and distant concern. "It's now," she said.

The new research, published Tuesday in the journal Nature Communications, adds to a growing body of scientific work that describes how humanity's continued emissions of heat-trapping gases could trigger climate "tipping points" or rapid and difficult-to-reverse changes in the environment.

Abrupt thaw of arctic permafrost. Loss of the Amazon rainforest. Collapse of the Greenland and West Antarctic ice sheets. Once the world warms beyond a certain point, these and other events could be triggered quickly, scientists warn, although the exact thresholds at which this would occur are still highly uncertain. "EY-mock").

These currents carry warm water from the tropics through the Gulf Stream past the southeastern United States before heading north into Europe. As this water releases its heat into the air further north, it becomes colder and denser, causing it to sink to the depths of the ocean and back toward the equator. This sinking, or "overturning" effect allows the currents to transfer enormous amounts of heat around the planet, making them hugely influential on the climate around the Atlantic and beyond. balance between heat and salinity which maintains the overturning movement. Part of the Atlantic south of Greenland has cooled markedly in recent years, creating a "cold spot" that some scientists believe is a sign that the system is slowing down.