The looming collapse of the Gulf Stream and its consequences
The Gulf stream is known as the Atlantic Meridional Overturning Circulation AMOC, is a current that flows into the Atlantic Ocean.
AMOC transports warm ocean water northwards towards the pole where it cools and sinks. Atlantic Ocean currents work as conveyor belt moving oxygen, nutrients, carbon and heat around the globe.
The AMOC can exist in two stable states : one strong and fast form, on which we depend. The other form is much slower and weaker.
In fact, This latter form could be responsible for the collaspe of the Gulf Stream. It would have catastrophic climate. According to estimates, it could happened between 2025 and 2095 with a central estimate of 2050.
But why might the Gulf Stream collapse ? Warming oceans and melting ice floes lead to an influx of fresh water into the oceans. If the waters become too cool or too warm, the conveyor belt comes to a halt. The density of the water then decreases, making it less able to flow.
As a result, the northern hemisphere will suffer harsher winters and rising sea levels. In the southern hemisphere, rainy seasons will be altered, impacting on food security.
Research carried out in 2022 showed that five dangerous tipping points may already have been crossed due to the 1.1C global warming recorded to date. These included the shutdown of AMOC, the collapse of Greenland ice cap and the melting of carbon-rich permafrost.
