Dr Karl

There's the USA on one side and Europe on the other side.

It's near the equator, so the sun's shining on it and it's heading north.

And because the sun's shining on it, it gets hot and the water evaporates and it gradually becomes more salty, but it's also carrying heat.

So it keeps on heading north and it delivers its heat to Europe and the east coast of the USA.

And then it gets close to the pole, the North Pole, and it gets cold and the denser water falls down to the bottom.

So it's the overturning.

So it overturns and then it heads back down and the current goes on and on.

And what they're worried about is that the two things can influence it, the overall change in currents due to global warming, but more importantly, the huge influx of fresh water coming from Greenland and melting ice in the Arctic, which can push it further south and in fact switch it off.

If it switches off, the east coast of the USA and the west coast of Europe will become a lot colder.

What can we do to stop it?

Six words, just six words.

Keep fossil fuel in the ground.

May?

Why May?

We're out of pollen season, are we?

Or we...

Carl, this is on you.

Would there be winds that are carrying the dust?

Yeah, maybe dust.

Yes, so there was a woman who had breast cancer, which happens to one in every eight women, one in 40, die.