According to one study, ocean currents are weakening in the Atlantic and may soon reach a tipping point. This will have far-reaching consequences for the climate.
In the Atlantic Ocean, ocean currents, which also include the Gulf Stream, have likely lost their stability over the past century and may now be facing a critical tipping point. That’s the conclusion of Niklas Boers, a climate researcher at the Potsdam Institute for Climate Impact Research, in the journal Nature Climate Change – He wrote an article in the Süddetsche Zeitung.
The Gulf Stream is considered a heating system in Europe because it also warms the climate off the British Isles and off the coast of Norway. The Gulf Stream is part of the larger Atlantic meridian flow system.
This transports warm, salty water northward to the sea surface, while cold, low-saline water flows deeper.
Based on evidence from Earth’s history, researchers hypothesize that circulation may differ between two different states of operation: between a strong circular motion currently observed and a much weaker one.
Because the flow system distributes large amounts of heat, it affects the weather around the world. A sudden transition from a strong state to a weak one will have dire consequences: it is likely that Europe will calm down, while hurricanes will intensify over the Atlantic. However, it is not yet possible to determine exactly when the transition to a weaker state will occur.
It can also affect the tropical monsoons. A few months ago, a study by the Climate Impact Research Institute showed that circulation is now weaker than at any time in the past millennium. The question is, is this just a short-term recession or a long-term trend?
It is not easy to investigate this, the strength of currents has been directly recorded for only twenty years. Although the measurements indicate a weakness,
It is still too short to make reliable climate predictions.
However, changes in ocean flow leave traces, for example, in water salinity and ocean temperature.
Bowers sees the main factor in the change as the increased flow of meltwater from Greenland due to rising Arctic temperatures. This fresh water is lighter than salt water and therefore tends to stay on the surface rather than sinking at depth. This slows the ocean circulation. As a result of climate change, the amount of precipitation and the amount of water flowing into the ocean by rivers has increased, and this may also contribute to the slowdown.
Cover image illustration.