As much of the Northern Hemisphere continues to bake in a year of unprecedented heat waves linked to climate change, one paradoxical consequence of rising global temperatures is that some areas of the world could become much colder. A study published this month by researchers at the Potsdam Institute for Climate Impact Research found that the Atlantic meridional overturning circulation (AMOC) current system could be on the verge of collapse. The conveyor belt system transports warm surface ocean water from the tropics, up along the coast of Florida to the northern Atlantic Ocean. Colder water sinks and is moved along...