The Eiffel Tower is buried part-way in snow. The London Eye has frozen shut. The ColosseumA vast stadium built by the Roman emperors Vespasian and Titus. It could seat between 50,000 and 80,000 spectators. It was used to hold gladiatorial contests and even mock sea battles. has become a skating rink. And Moscow has become so cold that the population has started living underground. We are in another Ice AgeA long period of time in which global temperatures are extremely cold..

This could be a montage from a second rate science fiction disaster film.¹ But, according to a research paper published at University College London (UCL), a deep freeze in Europe is a real possibility.

The research suggests that global warming could cause the collapse of the Gulf Stream - and it could happen as soon as 2025.²

The Gulf Stream is a current of warm water that flows north from Florida along North America's East Coast, before crossing the Atlantic to Europe.  

It heats up Europe, maintaining the moderate temperatures the continent currently enjoys. According to UCL's Professor David Thornalley, it is "equivalent to the energy from millions of power stations."³

The Gulf Stream is one part of the Atlantic Meridional Overturning Circulation (Amoc), a network of looping currents that pumps hot water around the world, from the Equator towards the North and South Poles.

As they move, these bodies of water partly evaporate. Salt levels in the remaining water are becoming more concentrated and this now-denser water sinks down, allowing warm water to rise up. And so the circulation continues.

But now, Greenland's freshwater ice cap is melting into the ocean, making the water less salineA solution of salt in water, or salty water (such as seawater). and dense, which has slowed down the Amoc system. It is currently at its weakest point in 1,600 years.⁴

If the Gulf Stream does completely collapse, temperatures in Europe could fall between 10 and 15C.

This would transform the continent completely. Food might become scarcer. Winters might become difficult to survive.

Yet Europe would not be the only place to suffer.

The sea level would rise up to 10cm on the east coast of North America, possibly placing the houses and livelihoods of many Mexicans, Americans and Canadians at risk. Wet seasons in the Amazon would be turned into dry seasons.

It is clear, however, that some people will be affected more than others. Climate change will fall more heavily on those in poorer countries, who rely the most on agriculture and have fewer tools for defence.⁵

Will this affect all of us?

Yes: There is no doubt about it. Countries in Europe will be most directly affected, but the Gulf Stream is part of a network which stretches across the entire globe. Everywhere will face one effect or another.

No: Most people will have to change their lives to survive in newer, colder temperatures. But, as is often the case, the ultra-wealthy will find a way to escape the effects that everyone else will be left to suffer.

Or... Scientists have only kept records on Amoc since 1980. We should not accept predictions based on such a small sample. The circulation pattern might be stronger than we think.

Colosseum - A vast stadium built by the Roman emperors Vespasian and Titus. It could seat between 50,000 and 80,000 spectators. It was used to hold gladiatorial contests and even mock sea battles.

Ice age - A long period of time in which global temperatures are extremely cold.

Saline - A solution of salt in water, or salty water (such as seawater).