What happens to London if climate change gets out of control?

A little-known oceanic current could collapse and wreak absolute havoc

- James Stewart

When you think about climate change, you probably imagine our world getting hotter. Ice melting, sea levels rising, miserable looking polar bears on lonely ice floes — you know the drill. For climate scientists like me that is likely where we’re heading — but there’s also a world in which the opposite happens and London actually gets colder… much colder. According to recent studies that’s something that could happen in many of our lifetimes. In fact, even as early as 2025. Given that is literally this year, it’s worth considering seriously.

I know it seems strange to speak of London getting colder when January felt like a Siberian winter and February very much picked up where that left off. London’s cold, what’s new? Fair question. To explain what I’m talking about we need to go on a quick jaunt around the Atlantic.

This is all about a giant, invisible, ocean current in the Atlantic Ocean. If we could see it, it would look like a huge piece of spaghetti draped from the northern to southern hemispheres and back again. It’s called the AMOC (Atlantic Meridional Overturning Circulation) and it works like our planet’s central heating system. It circulates water from north to south and back again in a long cycle within the Atlantic Ocean.

Its primary job is to move heat around the world, pushing 17 million cubic meters of water northwards every second. It makes sure the climate of Western Europe is much warmer than it would otherwise be. London is about the same distance from the equator as the cold regions of Canada, yet enjoys a much warmer climate because of this system.