"Shift in the Gulf Stream could signal ocean current collapse
Models show that as the Atlantic Meridional Overturning Circulation gets weaker, the Gulf Stream will drift northwards. There are signs that this is already happening, and a more abrupt shift could warn of more severe climate impacts.
A gradual northward shift in the Gulf Stream has provided more evidence that the system of currents that keeps Europe warm is weakening. What’s more, modelling suggests that any abrupt shift in the Gulf Stream could signal an imminent, catastrophic collapse in the ocean current.
The Atlantic Meridional Overturning Circulation (AMOC) is the flow of warm, salty surface water from the tropics to north-western Europe, where it cools and sinks, returning south along the ocean floor. The part of this circulation running from the Gulf of Mexico up the US east coast to North Carolina, where it veers east into the Atlantic, is called the Gulf Stream.
The AMOC is expected to lose strength as the melting of the Greenland ice sheet dumps fresh water into the north Atlantic, diluting the dense, salty AMOC water and slowing the rate at which it sinks and flows southward. Some research suggests that this is already happening, but scientists don’t have direct proof.
Now, a modelling study by René van Westen and Henk Dijkstra, both at Utrecht University in the Netherlands, has shown that a weakening AMOC would shift the path of the Gulf Stream so it follows the US seaboard further north before it veers into the Atlantic.
Moreover, the study finds the
Gulf Stream has already shifted northward by about 50 kilometres in 30 years, according to satellite data."
The AMOC is expected to lose strength as the melting of the Greenland ice sheet dumps fresh water into the north Atlantic, diluting the dense, salty AMOC water and slowing the rate at which it sinks and flows southward. Some research suggests that this is already happening, but scientists don’t have direct proof.
Now, a modelling study by René van Westen and Henk Dijkstra, both at Utrecht University in the Netherlands, has shown that a weakening AMOC would shift the path of the Gulf Stream so it follows the US seaboard further north before it veers into the Atlantic.
Moreover, the study finds the Gulf Stream has already shifted northward by about 50 kilometres in 30 years, according to satellite data."