Working from home with an underwater drone

现在我们出海,但不是人,because Nunzia Pirro, from the National Institute of Oceanography and Applied Geophysics, told me how marine scientists like her can now productively “work from home” and still be out on the ocean, by using shark-sized remote control vehicles to explore the depths and report on the effects of climate change. She’s studying how ocean currents, driven by the sinking of denser, heavier water and the elevation of more buoyant, lighter water might be changing…

Nunzia - Denser water is more heavy, so it stays at the bottom and less dense water stays at the surface. In order to move the ocean, this water has to mix so the dense water has to sink and the light water has to rise. So there is a changing of the current and we are trying to understand how this change occurs

Chris - Is it not just as simple as that in summer more ice melts and puts fresh water in the sea and that's less dense? Is that one of the mechanisms?

Nunzia - Yeah. Yeah. I mean this is a bad mechanism because look at the Arctic. If you have the ice melting, you don't have salty water. You have light water. So you have this light water on the top of the layer and then you cannot have the dense water formation. That's one of the mechanisms that stops the dense water formation.

Chris - I see. So if you put lots of light melted, icy water at the top, it stops that overturning, that sort of mixing and that could have consequences for ocean currents then?

Nunzia - Yes. Not only for the ocean current, but for us. For example, if you look at the Arctic, if all ice of the arctic melts, you don't have this mixing, this overturning. You don't have the current forming. And the current is important for the climate, so it means that we will get, for example, a colder Europe, because the current moves the heat through the globe.

Chris - This is the Gulf stream, isn't it? When you get hot water forming in the Gulf of Mexico, that comes traditionally up past the west of the UK and it's bringing enormous amounts of heat along and making Europe much warmer than it should otherwise be. If we melt the Arctic and push that back, because we stop that circulation, we will actually paradoxically get colder through global warming.

Nunzia - Yes, that's correct. So if this occurs, the Gulf Stream will not work anymore. So we will not have this water coming from the Arctic that usually the normal pattern is from the Arctic, it goes through the Gulf stream and goes to the Antarctic. Then from the Antarctic it rises to the equator, so in India for example. And if you don't have this dense water forming, you don't have this circulation. And so as you can see it's very bad for us, for all the globe for the climate.

Chris - Apart from just moving heat around, are those currents also moving nutrients? So are there knock on effects in that respect?

Nunzia - Yeah. Yeah, that's a good question. Of course they move nutrients. Nutrients usually stay at the bottom of the ocean and we don't have this mixing with this dense water formation. Nutrient stays at the bottom and this means that at the surface, we don't have food for the fish. Not having food for the fish means we will not eat fish.

Chris - I was gonna say no food for the fish ultimately ends up meaning no food for us doesn't it? How do you actually study this then? How do you register what these currents and these densities are doing and where they are?

Nunzia - We have several instruments. One of those is the glider. It's an autonomous vehicle, like a fish. It's around one meter long and 50 kilos. It's a small shark.

Chris - And how do you launch it, control it, and then get the data off of it?

Nunzia - Yeah, we actually have technicians that go to the sea and deploy it for a boat. You just throw away this small shark in the sea and then you pilot from your bedroom from here.

Chris - What?

Nunzia - Yeah, from your bedroom, from your house.

Chris - There's a TV advert in the UK where they're trying to push an internet service provider. They show a family landing an airplane in their living room and they say, We landed a plane on this network because it's got really good data rates. And so are you telling me you are basically working from home then? You fly this underwater thing from your bedroom?

Nunzia - Yes, yes, yes. We really pilot from home and tell him where to go up and down, which way to go and when it has to come to the surface. And when they come at the surface through the satellite, they transmit this data.

Chris - I get it. So it surfaces and talks to the satellite and sends you back what it has learned from all the other instruments aboard when it's been down. How deep does it go?

Nunzia - It depends. Usually one kilometer, but now technology is going fast and so they're trying to make these instruments go up to two kilometers. I mean if we consider the ocean goes up to five or six kilometers, there is a lot to discover. So the deeper he goes, the more we know.

Chris - I'm still intrigued by the working from home concept behind this. What, have you got an app on your phone or something or does it work on your desktop? What do you see? How do you control it?

Nunzia - So far, we have a website where you log in and there are several files where you tell this instrument how deep to go, how fast he has to go, and when it has to come up to the surface. And basically every time he goes up to the surface it's really nice because you can change plans.

Chris - How long can it stay at sea for?

Nunzia - Usually four months.

Chris - It's a long time.

Nunzia - It's a long time. Yeah. For one instrument it's a long time, but this is an instrument that costs 250k. It's a lot, but is still cheaper than a ship.

Chris - Well that was gonna be my next point, which is that historically to do this kind of work, someone like you would've had to have been at sea for months on end. And that would've obviously had a huge carbon footprint, a huge economic impact. And it would've been your time. Now you deploy an army of these and you are getting all that data without having to leave your home. Literally.

Nunzia - Yeah, yeah, yeah. That's really nice, because also the ship, as you said, is much more expensive for the environment and for our pocket.

Chris - And what have you learned so far? Because we started this talking about the importance of understanding ocean currents, these changes in density, and so on. Is it beginning to bear fruit?

Nunzia - Actually this dense water formation is not increasing. The question is why? Because the water is getting warm and this is one of the side effects of climate change. Of course you won't see it in one or two years, we'll see the effect in 30 years, so on a climate scale. But so far it's been three, four years that the dense water formation is losing power. If we think about what will be in 10 years, the scenario is not really nice.