An AMOC collapse is one of several key tipping points. Others include the melting of the Greenland ice sheet, destruction of warm-water coral reefs and boreal permafrost collapse. 

If any one of these tipping points is breached (if that hasn’t happened already) it would trigger progressive and irreversible changes in Earth’s climate systems.

Thanks to climate change, AMOC collapse could happen much sooner than anyone imagined. For Great Britain it would mean we’d actually cool down (at least in winter). The Gulf Stream would vanish, giving us the climate of Newfoundland (our latitude) – which has January temperatures of −1 °C to −27 °C.

But sub-zero temperatures would be the least of our concerns. Wheat and maize cultivation would lose half the land area it presently uses worldwide. That’s not good news if we must import all we need of these crops from abroad.