Jonathan Webb

It was produced by Amy Briggs and I'm Jonathan Webb.

I'll catch you next week.

There's been a lot of news about ocean currents recently, and one in particular.

The Atlantic Meridional Overturning Circulation, or AMOC, is at risk of collapse with dire global climate consequences.

So where do currents like this come from, and how do they work?

And what happens when these big water movements stop?

I'm Jonathan Webb and this is Lab Notes from ABC Radio National.

Helping me to get to the bottom of ocean currents today is Professor Laurie Monville from the University of New South Wales.

Hello, Laurie.

Before we focus on the Atlantic, can you give us a bit of a picture of these large ocean movements globally?

What creates them and what makes them get faster or slower?

So it's to do with incoming energy from the sun being spread around the globe by these movements, not so much the rotation of the earth, or does that come into it as well?

So there are big currents in multiple oceans which take warm water from around the equator towards the poles.

And what would make those currents change today?

And why are scientists paying such close attention to the AMOC at the moment?

What would be making it slow down?

Right.

So more carbon, more heat gets trapped.

How does that slow down a huge ocean current?

Right.