Scientists don’t really need more reasons to be worried about the changes in the ocean due to the climate crisis.

That said, the ocean just keeps giving them more, anyway.

Based on how the Gulf Stream fared during the last Ice Age, researchers are worried that warming temperatures will weaken it and cause a shake-up of climates around the world.

The Gulf Stream is part of the North Atlantic Gyre, a highway of currents that moves clockwise and help maintain the climate of the East Coast of the States and parts of Europe, too.

This new study, completed by scientists at University College London (UCL), concludes that the North Atlantic Gyre was stronger during the last Ice Age than it is today.

The fossilized remains of microorganisms called foraminifera suggest the Gulf Stream was around 0.6 miles deeper 20,000 years ago due to stronger winds and denser waters.

Dr. Jack Wharton, a lead author on the study, issued a statement.

“We found that during the last ice age, the Gulf Stream was much stronger because of stronger winds across the subtropical North Atlantic. As a result the Gulf Stream was still moving lots of heat northwards, despite the rest of the planet being far colder.”

They believe this has serious implications for the future, when wind patterns and the like will change as the climate crisis deepens.

“If in the future winds are weaker, as shown in a recent study using climate models, it could mean a weaker Gulf Stream and a cooler Europe.”

And of course, the Gulf Stream is only part of a more complex system. It’s called the Atlantic Meridional Overturning Circulation (AMOC), and involves the northward flow of warm water in the upper layers of the Atlantic.

It also involves the flow southward of cold, salty water, explains study co-author David Thornalley.

“Rather than the established conveyor belt metaphor, perhaps it is better to think of the AMOC as a series of interconnected loops. There is a subtropical loop – that the Gulf Stream is part of – and a subpolar loop, which carries heat further northwards into the Arctic.”

They’re keen to do more research to try to predict how the Gulf Stream might be affected this time around.

“During the last ice age, our findings show that the subtropical loop was stronger than it is today, whereas the subpolar loop is thought to have been weaker. Therefore, when investigating anthropogenic climate change and the AMOC, we need to consider how these different parts may change and what climate impacts each is associated with.”

Scientists have already worried that the AMOC has been weakened, with glacial water from the Arctic disrupting deepwater formation and preventing tropical water from reaching Europe.

If the AMOC were to collapse entirely – which is possible, if unlikely – it could cool parts of Europe by 18° to 27°F.

“It’s not always recognized how much ocean currents are responsible for transferring heat around the planet and shaping our climate. Paradoxically, the warming of the climate could cool down much of Europe by disrupting the AMOC. Our new research adds to this understanding, and shows that the weakening of the winds which drive the Gulf Stream could reduce the circulation of heat, further affecting the continent.”

Only time will tell.

But that doesn’t mean we shouldn’t try our best to stop it.

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