If you're one of those people living in a cold climate who thinks a bit of global warming doesn't sound too bad, you might want to think again. A study of the likely effects on Atlantic Ocean currents has resolved previous contradictory research in a way that is very bad news for the future of the UK, Ireland, Iceland, and Greenland. While the rest of the world warms, these countries, already not renowned for balmy temperatures, could find themselves much colder than they already are.
London is at the same latitude as southern Labrador and Sakhalin. The major reason it has a different (and to most people, preferable) climate is the powerful current pushing waters from the tropical Atlantic to warm northern Europe. Popularly known as the Gulf Stream, this warm flow is part of what scientists call the Atlantic Meridional Overturning Circulation (AMOC).
It wasn't always like this. Climatic records show that many times in the past, most notably 12,000 years ago, the AMOC weakened or stopped entirely, causing temperatures in the north Atlantic and northern Europe to plunge.
For 20 years, climate scientists have been debating the risk of such an event happening again. The research even inspired a blockbuster disaster film, however most climate models suggested the weakening would be mild. Now, a paper in Science Advances argues that these models are missing a key component. Once this is included, the authors conclude, Britain's long-term future looks far bleaker.
Allowing for the effects of freshwater flowing from the Arctic to the Atlantic suggests North America will warm less than expected, but that Britain and Iceland will actually cool while the world as a whole warms. Liu et al/Scientific American