The Gulf Stream, a deep-water circulation system that regulates the climate around the globe, is at its weakest in more than 1,600 years, according to new research.
A study by University College London and Woods Hole Oceanographic Institution said the Gulf Stream, which is also called the Atlantic Meridional Overturning Circulation (AMOC), has been declining since the mid-1800s.
The warming began at the end of the “Little Ice Age” in 1850, which has contributed to the weakening as well as global warming.
AMOC is now 15 per cent weaker than in 400AD, which has thrown into dispute previous theories that a collapse of the system would take centuries to occur.
If the trend continues its effects could be felt as far away as North Africa. Further weakening will cause severe winters in western Europe, rising sea levels on the US East Coast and more extreme weather occurrences such as winter storms, drought and flooding.
Lead author Dr David Thornalley said the weakening was "predicted to continue in the future due to continued carbon dioxide emissions".
AMOC works by carrying warm water north from the Gulf of Mexico to the North Atlantic where it releases its heat before becoming cooler. As it cools it becomes denser and sinks before travelling south.
However, global warming has disrupted the system as less dense freshwater, caused by melting ice in the Artic, enters the North Atlantic. Unable to sink as deeply, the AMOC current is weakened.
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