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10 Things to Know About - Season 11 Episode 5 -
Carbon
Carbon
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00:00Why are we so resistant to change and what can we do to challenge the status quo?
00:06And how do invasive species threaten nature and their way of life?
00:10We'll be looking into all this and more on 10 Things to Know About.
00:22This week we're looking at carbon, the vital element that connects all life on Earth,
00:27our geological past and our climate.
00:43We all have an idea of what carbon is.
00:46It's in diamonds and in pencils, in coal and in fizzy drinks.
00:50And life as we know it would not exist without carbon.
00:54Carbon can exist as a solid, liquid or gas.
00:57And it's an important part of DNA, the molecule that stores the genetic instructions for human life.
01:03So how does this element that is so central to our existence pose such a threat to our planet?
01:11I'm at the otherworldly landscape of the Byron to meet Michelle McKeown to discuss how carbon builds the very fabric of our world.
01:19Carbon is an element and it's fundamental to all life on Earth.
01:29So me and you, Fergus, we're made up of carbon, so our plants and animals.
01:34And it also comes in an inorganic form as well, which you can find in soils, in rocks, in water and in our atmosphere as carbon dioxide and methane.
01:44For millions of years, nature has kept a delicate balance, removing just the right amount of carbon dioxide from the air through a process known as the carbon cycle.
01:53Freeze will take carbon dioxide in from the atmosphere and store it in the biomass of that tree.
01:59Also, in oceans, we have dissolved bicarbonate.
02:03So that carbon then is being used up by marine organisms to form kind of their shells.
02:08And we're here in this stunning vista of the Byron, but what role does carbon play in the formation of the Byron?
02:17So this is actually an amazing carbon store that we're sitting on.
02:21So this is calcium carbonate, so it's inorganic carbon.
02:24And 340 million years ago, we would have actually been in a tropical ocean.
02:30Wow.
02:31Yes.
02:31Not today, it's pretty cold today.
02:32Not today, no, no.
02:33It was a long time ago.
02:35And there would have been coral and marine organisms sucking some of that carbon out of the ocean and actually storing it in the shells.
02:44And then when these organisms died, their shells would have sank to the bottom of the ocean and formed this kind of calcium carbonate mud.
02:52So under millions of years and through lots of different pressure, it would have created limestone.
02:57Now, what we're sitting on here today, these limestone pavements, they have unique kind of landforms of different shapes to them.
03:05So we have turlocks, we have cave systems here, we have our limestone pavement.
03:10Through rainwater and through groundwater, what's actually happening is there's a weak carbonic acid in that water and it's slowly dissolving some of that ancient kind of carbon that we're sitting on in these rocks and actually brings it back out to the Atlantic Ocean.
03:28So it can then be used by other organisms to form their shells.
03:31And it's a nice example of this carbon cycle.
03:34Since the Earth's formation 4.5 billion years ago, carbon dioxide or CO2 levels have varied wildly, shaping our planet's climate and life itself.
03:56Early volcanoes filled the air with CO2 until the first plants formed, absorbing CO2 and cooling the planet.
04:03Over the last 800,000 years, CO2 fluctuated with ice agents, rising and falling due to changes in the Earth's orbit.
04:12However, the Industrial Revolution has increased CO2 levels and changed our climate at the fastest rate ever recorded in human history.
04:21This is where humans have really played a role in accelerating climate change because what we've been doing is taking these old stores of carbon like our coal, our gas, our oil and burning them and emitting that carbon back into the atmosphere as carbon dioxide.
04:38Now, the greenhouse effect's important. We need it for life on Earth. The problem is that we as humans have accelerated the carbon cycle.
04:44We all know that we need to reduce the amount of fossil fuels that we use, but is that enough?
04:50But we also need to have a look at our landscape and how we're using it as well.
04:54Only 11% of our land cover is actually trees. Also, peatlands as well.
04:59Actually raising the water table would allow less of that carbon to be released back to the atmosphere.
05:04And the ocean is one of the biggest sinks of carbon dioxide. Is that right?
05:08Yeah, that's correct. Yeah. So being able to understand kind of this role that the ocean plays in that carbon cycle is incredibly essential.
05:28To explore how rising CO2 levels impact our oceans and shape Earth's climate, scientists are pushing the limits of marine exploration.
05:38Tom Crean is one of two research vessels run by the Marine Institute in Galway.
05:44And like the great man she's named after, is dedicated to taking to the high seas to discover more about our planet.
05:51She plays a major role in helping us to improve our understanding about the ocean current system of the Atlantic.
05:58I'm here to meet Audrey Morley, whose research is helping to tell the story of our oceans.
06:03I'm a paleoceanographer, so I study the ocean and the ocean climate in the past.
06:11And I'm particularly interested in the AMOC, which stands for the Atlantic Meridional Overturning Circulation.
06:17The AMOC is a system of currents.
06:20It transports warm waters from the tropics to the high latitudes at the surface, and then cold water at the bottom of the oceans, out of the Arctic, into the southern latitudes.
06:32So you think of it as a conveyor belt.
06:34It is bringing heat to the high northern latitudes and cold waters back south into the south of the Atlantic.
06:40The heat that is transported to northern latitudes is why our weather and climate here in Ireland is so mild and wet.
06:48Because not only do we get heat, but we also get a lot of moisture with it.
06:53And why are scientists so interested in AMOC at the moment?
06:56There have been signs that AMOC might be decreasing, and that could have really important consequences for our weather and climate here.
07:04Because even a small decrease in the amount of heat and moisture that we are getting to Ireland would change our climate significantly.
07:13Our winters would get colder. We would have more extreme climates. Seasonality might change as well.
07:19We would have more extreme storms, most likely.
07:21And then our infrastructure, economy and agriculture needs to cope with all of these changes, which is not a small thing.
07:28And some of those things are already kind of baked in in terms of climate change.
07:31But actually, if AMOC was to be put on top of that, then who knows?
07:34Well, who knows? You're going to find out.
07:36That's one of the goals, yes, to find out what the impacts are so that we can prepare for them.
07:43Scientists have been monitoring the AMOC since the early 2000s, but the ocean circulation responds on much longer timescales.
07:51Aboard research vessels like the Tom Crean and Celtic Explorer, Audrey and her colleagues collect water samples and marine cores
07:57to investigate what was happening in our oceans and atmosphere thousands of years ago.
08:01Her last expedition was in 2023.
08:07To get the Climate Archive, we deploy two different types of equipments.
08:12One that's called a multi-core and it takes small cores of the very surface of the ocean floor.
08:18And then we deploy a gravity core that will take up to six metres of sediments from the chosen site.
08:24Back at her lab in the University of Galway, Audrey shows me one of the cores she collected from the seabed where deep Atlantic currents flow.
08:34On their path, they carry sediments with them.
08:37When the currents are very strong and the AMOC is strong, then the grain size that the currents are carrying is larger.
08:43But when they're weaker, the sediment size will decrease as well.
08:48So if I take samples from this core and go back in time or down the core, I can measure changes in grain size and therefore infer changes in AMOC strengths.
09:00Okay, very good.
09:00And can you tell how far back in time you're going according to the depth of the sediment?
09:06That is actually the first step.
09:07We need to know how old this core is.
09:10So in order to do that, I have to take samples at certain intervals throughout the core to radiocarbon-dade fossil material that is preserved in the mud.
09:19And these fossils that you're looking at, what creatures are they from the past?
09:22So we use foraminifera, or forams for short.
09:26And they are tiny plankton.
09:28And during their lifetime, they build a shell, and that shell is preserved in these cores.
09:38Sediment samples from the seafloor can reveal how deep ocean currents respond to climate change.
09:44This sample will be gently shaken for two days and then sieved to separate the clay, silt and plankton from the tiny microfossils that have an ancient story to tell us.
09:54Wow.
09:55So they're microfossils from a couple of thousand years ago?
09:58Yes.
09:59They look like tiny little popcorn.
10:01Really?
10:02Please.
10:04Oh yeah, they totally do.
10:06In order to take the forearms out of the tray, because they are different species, we have these little slides where we put them in.
10:14And I use a little bit of clean water to wet.
10:17So I gently approach it.
10:19Well done.
10:20Pick it up and then place it in here.
10:23But you're just looking for the popcorn-shaped ones.
10:25In the popcorn-shaped ones, there are over 20 different species.
10:30Okay.
10:30So you have to identify them correctly.
10:32Oh wow.
10:33And how many are you looking for?
10:34Maybe 500 would be enough.
10:36Sometimes it's...
10:37Do you have to pick 500 out of this?
10:38Yes.
10:39Good luck.
10:39The dating and analysis of marine sediment pores can help reveal how Earth's climate and ocean circulation has varied in the past.
10:56Using these natural climate archives, scientists estimate that the AMOC is between 3 and 14 million years old.
11:04Over that time, the AMOC has experienced natural variations, and understanding the complexity of this ancient system takes close collaboration.
11:12Audrey's data can help climate modelers like MetAaron's EndaOD to test and refine AMOC models.
11:18We want to discern between human-forced variations versus the natural oscillations which can last decades, centuries, and even millennia.
11:29If we can recreate what the paleontologists observe, then we can be confident that what we're predicting the future is reliable.
11:37AMOC responds to changes in climate, ocean temperature, and salinity, which can be caused by a number of factors, such as melting fresh water from the ice sheets.
11:47Enda can simulate these changes in the models, but the computational power required to capture such a vast ocean in detail can be very expensive.
11:56Instead of doing that, we look at the key areas that really matter, that really affect AMOC, and we use a very high resolution grid for those places.
12:03We get much improved AMOC simulations, but at a much lower cost.
12:07And what are some of those key areas that you're looking at?
12:10So some of the key areas include the Gulf Stream separation off the coast of America, the sills between the Arctic and the Atlantic, that's between Greenland, Iceland, and Shetland.
12:21And believe it or not, even the Mediterranean is important because of Mediterranean outflow at mid-depth also affects AMOC as well.
12:28Enda is particularly interested in the Denmark Strait, where deep Arctic water flows over ridges and sills into the Atlantic.
12:37Traditional models show how the temperature changes by depth in this area, but they can miss important details.
12:43Their blocky grids average out temperatures and fail to represent the flow near the seabed.
12:48Regional models, on the other hand, are far more detailed.
12:52They follow the shape of the ocean floor more closely, adding smoother layers and capturing the flow near the seabed as it travels from the Arctic into the Atlantic.
13:01AMOC has kind of hit the news headlines a bit over the last few years about collapsing in the next 50 years or 100 years.
13:26What's kind of most sober assessment of it?
13:28Some of the studies, they're actually deliberately collapsing the AMOC.
13:32They deliberately enter an unrealistic amount of fresh water just to see what would happen.
13:36Because it's very important to understand if it did collapse, how would we deal with that situation?
13:41Yeah.
13:41However, it's not often reported that they are quite unlikely events in the future, and that's something you need to be clear about.
13:47The more likely is a gradual slowing down of 35 to 45 percent by 2100.
13:52And that's kind of where we're concentrating in Med-Aaron, but of course, research is active and we're always watching the latest literature.
14:00Understanding all this is kind of crucial for the future.
14:03Is there anything else we can do to kind of help?
14:05We need to reduce our carbon emissions.
14:09Each effort we make in that will make the extreme events less likely.
14:14We really want to avoid extremes.
14:16Inevitably, there will be some adaptation needed, but the degree to which we have to adapt will depend on how much we mitigate in the first place.
14:23And the work that you are doing and your colleagues are doing is to kind of give us a better picture for the future so we can plan and adapt.
14:29Absolutely, yes.
17:46Let me know, what's this is.
17:48to do this. And so if you want to take carbon out of the air, where do you even begin to tackle that
17:55problem? The process is described as direct air capture. So you need a material, you need to
18:01design a material that picks up the CO2, that absorbs the CO2 from the air, and also potentially
18:08releases it on demand. Wolfgang and his team have spent years designing and testing a number of
18:15materials to draw carbon dioxide out of the air. A key development was this material that contains a
18:21special surface that binds the CO2 molecules and releases them again when heated. We decided to go
18:28with this approach because it allows us to use waste heat. What does waste heat mean? Heat that is
18:37generally associated with industrial processes and is difficult to harness. So for instance in Ireland
18:44it would mean in 2030 I think approximately one-third of the electricity used in Ireland is used in
18:52data centers. However, most of this electricity that enters the data centers translates to waste heat.
19:02Wolfgang and his colleague Sebastian show me how the air filter device works. As air is drawn in,
19:08the CO2 molecules stick to the innovative material inside. By monitoring the levels at the filter exhaust,
19:15we can see that the levels have dropped, indicating an impressive 90 percent of the carbon dioxide has
19:20been captured. But this isn't just a lab experiment. We're heading to Dublin airport where the technology is
19:29being put to the test in the real world. So it's going very well. The instrument performs very reliable
19:36across all weather conditions even today. So the humidity does not really influence the performance of
19:43the instrument. We capture approximately two to five tons of CO2 per annum. There's also some room for
19:52improvement. For instance, the insulation or the heat management in the system could be a little bit
19:57improved. This would allow us to run faster cycles and the productivity would be higher and the energy
20:04consumption would be lower. So now you see inside of the instrument. So this is actually the capture vessel
20:11where the porous material is inside. And so how much of your absorbent material is in here? So in the laboratory
20:17we had 500 grams and here we've got now 100 kilograms of adsorbent in there. 200 times more. 200 times more.
20:25Brilliant. The airport is an ideal location to test a direct air capture device and it could offer
20:32valuable opportunities for the future. The aviation industry emits significant quantities of CO2 and
20:41the industry needs to adopt sustainable aviation solutions to meet the climate target. In particular,
20:48the aviation industry will in the future more and more use sustainable aviation fuels for which CO2
20:56could be a feedstock. We are also not very far from greenhouses here at the Dublin airport where
21:02strawberries are grown. The test here allows us to demonstrate the technology to the agricultural
21:09industry which could use CO2 to enhance growth in greenhouses to increase the yields. So there's a lot of
21:16different benefits. There are a lot of different benefits.
21:29Direct air capture isn't a silver bullet for reducing our CO2 emissions and the technology has to run
21:35efficiently to be truly sustainable. But these portable systems could be scaled up to help us build a cleaner,
21:42lower carbon future. So Wolfgang, what's the long-term goals of this project? Where do you want to see it go?
21:49We are at the moment designing a 400-ton system. A system that captures up to 400 tons of CO2 per annum.
21:58We would like to develop this technology to be used in conjunction with waste heat,
22:03with waste heat suppliers, data centers, with incinerators. Excellent.
22:08From the outside, this system looks deceptively simple. But inside these boxes is cutting-edge technology
22:15that represents a decade of research. And this system has such exciting potential, not only as a tool for the circular economy,
22:23but also as a way to help clean up our air and secure our planet's future.
22:37That's our 10 things to know about carbon. Next time, we explore the hidden world of bacteria
22:43and the urgent fight against antimicrobial resistance.
23:13We'll see you next time.
23:27We'll see you next time.
23:29Bye.
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