The Atlantic Meridional Overturning Circulation (AMOC) is a vast current that helps move water and energy right around our planet, from top to bottom. Scientists say it is slowing down — and might stop altogether, with dire consequences for the global climate if it does.  So how do major ocean currents work, why is it slowing down, and what will happen if it collapses? You can binge more episodes of the Lab Notes podcast with science editor and presenter Jonathan Webb on the ABC Listen app (Australia). You'll find episodes on animal behaviour, human health, space exploration and so much more. Get in touch with us: labnotes@abc.net.au Featuring: Laurie Menviel, climate researcher at UNSW This episode of Lab Notes was produced on the lands of the Gadigal and Menang Noongar people.