Our global ocean currents move enough water to dwarf the flow of all Earth’s rivers. This worldwide circulation is driven largely by density and the movements of cold, salty water versus warmer, fresher water. The pump behind this action lies in the North Atlantic, where cold, salty water sinks down in the Atlantic Meridional Overturning Circulation, or AMOC. Among other things, AMOC is responsible for Western Europe’s relatively mild climate compared to similarly northern lands.
Unfortunately, as our world warms, AMOC gets weaker. That means less cold water sinking in the North Atlantic and a smaller driving force behind global oceanic circulation. There is even a small but real chance that global warming breaks our ocean current system entirely and drastically changes climates around the world in ways that cannot be easily fixed. Watch the full video to learn more. (Video and image credit: It’s Okay To Be Smart)