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Digging Deeper: Stress and Gestation

Evolutionary medicine PLOSable PLUS

Digging Deeper: Stress and Gestation

Digging Deeper

Research is hard work. Researchers may spend months, years, or even decades collecting data. Sometimes when researchers analyze that data and try to present it in a handful of published pages, it can be difficult to include every single thing they did, or to discuss all the problems they encountered in the experiment or study.

Hacking Nature

Hacking is a word that is often tied to something bad. However, there are times when hacking can be for something good. Think of it as a tool that can be put to use for good or bad. We also think of hacking as something only done with computers, but can we hack other things? Dr. Biology sits down with scientist Klaus Lackner to talk about how he is hacking the environment in order to pull carbon dioxide (CO2) out of the air. If he succeeds, it could help reduce CO2 in atmosphere and redirect it towards better uses.

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Topic Time
Why is having too much CO2 in the atmosphere bad? 01:46
Where is the extra CO2 coming from? 05:32
Have we increased the amount of CO2 in the atmospher? 07:00
You are working on a way to pull CO2 out of the atmosphere. 08:14
How can we get CO2 back out of the air? 11:25
Fuels, plastics, and algea. 17:38
It this all works do we need to worry about carbon emmission? 19:13
Its like a giant train that is difficult to slow down and stop. 22:14
Is ther something a person can do to help? [slowing down the train] 23:28
How to get the CO2 already in the atmosphere. 25:37
The detials of balance [atmosphere, biosphere, and ocean] 26:46
How are you pulling CO2 out of the atmosphere? 28:12
Three questions 30:38
When did you know you wanted to be a scientist? 30:46
What would you be if you could not be a scientist? 31:08
Advice for someone wanting to become a scientist. 32:07
Thank you 33:37
Sign-off [Center for Negative Carbon Emission] 33:45

Transcript - (PDF)

Dr. Biology:  This is "Ask a Biologist," a program about the living world, and I'm Dr. Biology.

Hacking, a word that's often used today. It can mean something bad, such as hacking into a computer to get personal information or to do other harmful deeds. Hacking can also be used to describe pulling together a team of people to collaborate on a computer software project.

There are even hackathons and hack fests held by different groups around topics like security, technology, and gaming.

What if we turn our attention to other areas besides computers? Can we hack other things? Like, maybe, nature? If we could, what would we do that nature does not already do better than humans?

Today, we'll be talking about one area where hacking nature might be important for our planet. It involves the CO2 molecule, also called carbon dioxide. As we know, CO2 is the primary greenhouse gas in our atmosphere that is causing the planet to warm.

For today's show, my guest is Klaus Lackner. He's a professor in the School of Sustainable Engineering and the Built Environment in the Ira A. Fulton Schools of Engineering at Arizona State University. He's also the director of the Center for Negative Carbon Emissions at ASU.

His research with carbon, and how we might capture carbon dioxide from the air, is one way we might help the environment. In this case, we might be able to hack the environment, to reduce the carbon in our atmosphere. Professor Lackner, thank you so much for joining me today to talk about this important topic.

Klaus Lackner:  I'm glad to be here.

Dr. Biology:  When people talk about changes in climate, we talk a lot about the carbon dioxide molecule. Why is having more CO2 in the air a bad thing?

Klaus:  If there's just the right amount, it's actually a good thing. There is a CO2 molecule, which is a carbon atom with two oxygens attached. It is a tiny part of the atmosphere. It used to be 280 parts per million. For every million molecules in the atmosphere, there are 280 which are CO2.

That's actually very important, because unlike the nitrogen in the atmosphere, unlike the oxygen in the atmosphere, which are the main stuff, the CO2 absorbs infrared light. That makes it different.

Dr. Biology:  In what way does it make it different?

Klaus:  If you think about the earth as a whole, we are having sunshine coming in. A little bit of it is reflected back out in the atmosphere. There's light bouncing right off that never affected us. Most of the light, two‑thirds of it, at least, manages to get down to the ground. It gets absorbed. That light has energy.

That energy now is absorbed and turns into heat. The planet has to get rid of that heat. On average, it's in perfect balance. For all the light coming in, it has to go back out. It turns out if you have a temperature like the planet has, this energy is radiated back into space, as infrared radiation.

It's different from light in that the wavelength is a lot longer. The remarkable thing about the atmosphere is, in the visible light, in the short wavelength, it's perfectly transparent. The sunlight coming in comes all the way to the ground, but the infrared going out is stuck. The atmosphere absorbs it again on the way out.

The fact that we are not an ice ball, which the earth at some point has been, is due to the fact that we have a little bit of CO2 in the atmosphere, which is just enough to keep the temperature in.

Dr. Biology:  It's that balance. A little bit of CO2 is really important. Otherwise, we're an ice ball.

Klaus:  If you have too much, the planet gets warmer and warmer. The first person who actually figured this out was a famous mathematician and physicist in the early 1800s, Fourier. Fourier wrote a little treatise ‑‑ it's a little booklet ‑‑ in which he said the temperature of a planet will depend on what kind of atmosphere it has.

He had figured out the principle. He didn't know anything about CO2. He didn't know anything about infrared, really. That was all still in the future, but he got the idea right.

In the mid‑1800s, Tyndall, in Britain, did a number of measurements. He said, "Well, nitrogen doesn't absorb any infrared. Oxygen doesn't absorb any infrared. The only two gases in the atmosphere which actually do are CO2 and water." The water comes and goes, with the rain, and you can't change it. The CO2, we are changing.

In 1897 or '98, Arrhenius, a Swedish chemist actually, started to work this through, and he calculated how much warmer the earth will get, if we double the CO2 in the atmosphere. He got it just right.

The bottom line is there's nothing really new in the greenhouse effect. We understand it quite well, and the planet will get warmer. The next big question is what will that do to the planet?

Dr. Biology:  And reasons for it getting warmer. Where is the CO2 coming from, the extra CO2?

Klaus:  Since the end of the Ice Age, the CO2 in the atmosphere has been constant. It has been around 280 parts per million. Then with the beginning of the Industrial Revolution, the CO2 in the atmosphere is starting, first slowly, then faster to go up. The reason this is happening is because we are burning fossil fuels.

We have burned coal, then we discovered oil, and now we use natural gas, and those three things add to the atmosphere. As a matter of fact, since we still can account for all the coal and oil and gas we put out, at least approximately, we actually know that the CO2 should have gone even more. Some of the CO2 which we put out has gone somewhere else.

Most of that is probably in the ocean because the ocean dissolves that CO2. It's carbonic acid. If you bubble CO2 into water, it becomes slightly acidic. That's where the CO2 goes that doesn't stay in the air.

Some part of it also has gone into biomass. We have grown trees, we have more leaves on trees because it's warmer and there's more CO2, but then we also cut down a lot of trees. In the total probably the biomass has lost.

Dr. Biology:  We've increased the amount of carbon dioxide in the air?

Klaus:  Yes, and substantially. We started at 280 parts per million, and we are now at 400 parts per million. When I started to work on this in the early '90s, it was 360 parts per million, and it is now going up by a little more than two ppm every year.

The general consensus right now is, and people can argue about the details, that things become awkward, or possibly harmful, at around 450 parts per million.

Now, there are outliers on both sides. There are some people who say we really should have stopped at 350 parts per million. Other people say, maybe, 550 is manageable, but I think there's hardly anybody who says he can do this indefinitely.

As you put more and more CO2 out the effect will get larger and larger. Once you put it there, most of it will not go away.

Some of it will go in the ocean, some of it will go into biomass, but it's fair to say that half of it is still there in a couple of hundred years from now. To get rid of that last quarter, you probably talk tens of thousands of years.

Dr. Biology:  This is a perfect time for me to mention, you're working on a way to remove some of that extra carbon dioxide?

Klaus:  Yes, and part of the reason I got involved in this is I am very much convinced that we need a lot of energy for today's 7 billion people, possibly in the future 10 billion people, to have a decent standard of living.

Right now, the vast majority of this energy comes either from coal or oil or gas. We can argue whether or not we run out. The answer is, of course eventually we will run out.

Did we make a very big mess beforehand? Will we run out in the next decade? In a hundred years from now? Or will we run out in 500 years from now? That's a hard question to answer, but if you look at how much coal is in the ground, we definitely will not run out in the foreseeable future.

In the 1980s South Africa, because of its appalling apartheid policies, was actually embargoed by the rest of the world. Specifically, they had no access to oil, but they have internally plenty of coal.

They demonstrated back then that you can take that coal and convert it into gasoline, which tells me that in some way or another if we were actually sure there is no more oil, we might actually start going after the coal.

What concerned me was, if you look at the budget from the other side, and says, "How much CO2 can we possibly afford to put in the atmosphere?" We have way too much fossil carbon to make this work. We are not resource limited, in my view, in the sense that we run out of fossil carbon. We are environmentally limited.

Dr. Biology:  To actually put it, maybe, in this view is we have too much of this.

Klaus:  We have too much of it?

Dr. Biology:  For our own good.

Klaus:  For our own good. Or we have to figure out how to not get into trouble. Very clearly, we either abandon fossil fuels, or we figure out how to balance the books. This is where I started. We will have to have a net zero balance of carbon emissions. If we emit, we have to take it back.

What has changed, from my perspective, in the last decades, is that we look better and better at having other alternatives. They are still decades away. By now, we have put out so much CO2, that we may not have a choice, but to get it back and put it somewhere.

We already are too late to say, "We just stop." If we stop today, we will live with a 400 ppm climate.

If by magic, I could say, "We, from here on out, will hold the line at 400 ppm. Next year, you are allowed a little bit of emissions, because the ocean will take a little."

The unfortunate part is the ocean will take every year less. In a matter of decades, your CO2 emission has to go to zero, to hold the 400 ppm line, or very, very close to zero.

Dr. Biology:  Your research is, "How do we get it back out of the air?"

Klaus:  My research is right now focused on how to get it back out of the air. A larger picture I'm worrying about is what do we do with all that carbon we collected?

Dr. Biology:  Let's start with the first one. How do we get it out of the air?

Klaus:  A tree can do it. If you look at a tree, a tree stands out there in the wind. It sees sunshine. All those leaves absorb CO2. We said, "Well, we need something like a leaf so the surface has to be sticky for CO2." It binds C02. Then at some later time, we take the CO2 back off.

Over the last ten years, nearly, we are working on a process where we use a material that when it's dry, really likes CO2. When it's wet, it gives it back.

Dr. Biology:  You use that for storage?

Klaus:  No, we use it for capture. It's a temporary thing. My first goal is to stand in the dry, desert air here in Phoenix, and let the surfaces we created, these filters, if you wish, the air moves over it and things stick to the surfaces. In our case, it's the CO2, and when they're dry, it sticks very well.

Then we collect our filters in a box, make them wet, and now the CO2 level in the box goes up to about five percent. The material now, when it's wet, doesn't want the CO2 anymore, and that's [inaudible 00:12:58] .

We can pull that out, and now we have a stream of five percent CO2. We can upgrade to 100 percent CO2, because that's what a power plant would be doing.

We now have a problem which is very similar to them, where we directly feed it into a greenhouse, where somebody might want the CO2, or we figure out how to have the CO2 react with minerals to form carbonates.

That's how we would throw it away. We either use it, or we find a way of thinking of it as a waste.

Dr. Biology:  Do you see that as a storage method, or do you see that just as a waste?

Klaus:  I ultimately would think of it as a waste. I think we actually, philosophically, haven't quite gotten to this point, in our discussions. I give you a simple example how it changes the way you think about the problem.

Let me say hypothetically, I don't smoke, but let's assume I did smoke. I have the horrible habit of throwing the cigarette butts out along the highway as I go along. I come to you and say, "Since you complained about it, I have figured out how to reduce my cigarette butt production by 20 percent, because I'm smoking longer cigarettes. Aren't you proud of me?"

Are you? Not really. You would say, "Look, you made a mess beforehand. Yes, you make a smaller mess, but you're still making a mess. You need to properly dispose of these things. You can't just throw them out of the window of your car."

The same would be true for sewage. The same would be true for the garbage at home. By simply phrasing the problem as a waste problem, it becomes very clear you shouldn't litter. You shouldn't dump CO2 into the atmosphere, period. To the extent that it ended up there, you are responsible for taking it out.

It's not good enough to increase efficiency. I don't want to discourage that. By the way, the waste disposal way of looking at it, clearly doesn't discourage it. If I look out of the window, when the garbage truck comes by, it has written in big letters, "Reduce. Reuse. Recycle." It's motivated by the fact that, otherwise, the garbage has to be landfilled. That costs money.

Everybody agrees it's better not to make it. That's where the reduce comes in. If you can avoid landfilling it, because you still have another use for it, please reuse it. If you can't reuse it the same way, maybe you find another use for it, which you would call recycling.

That's all good, but it's driven by the fact that it's a waste you wanted to get rid of. Here too, the CO2 is the waste product of making energy. Unfortunately, it's a very, very, large waste stream.

Here in the US, we produce about 15 to 20 tons of CO2 per person, per year. We don't use materials at that scale, with the one exception, that's water. Everything else, we use at much, much smaller rates.

I'm very skeptical that we find lots of uses for CO2, which absorb this enormous stream of CO2, which comes from our energy consumption. The only exception is if we make fuel again. In that case, we are not using fossil fuel anymore.

Dr. Biology:  If you don't use fossil fuel, then you're not adding to the CO2 in the atmosphere. Then if it's used as energy, now we have a whole new other option for getting our energy.

Klaus:  Envision a world, which uses solar energy. Sometimes you have sunshine, and sometime you don't. You, on average, want to have enough energy. Sometimes you will have too much. When you have too much, make fuel. You collect CO2 and water. So to speak, with the energy, you "un‑burn" it.

You take the oxygen out of the H20, and one of the oxygens out of the CO2. Now you have CO and hydrogen. Chemists call that syngas or synthesis gas, which is the starting point of making plastics, and making fuels. The energy you put back in, by using a solar panel.

Now you have new fuel. The energy in this fuel came from your solar panel. You can drive a car, or fly an airplane. That airplane then consumes that energy. In the process it produces, again, CO2 and water. You take that back out of the atmosphere, and the cycle is perfectly closed.

Dr. Biology:  You actually mentioned fuels and plastics. That's actually an important point, because the fossil fuels aren't used just for gasoline, or some kind of a product that we're going to use for powering things.

Klaus:  Yes, you can get the plastics from the same source, but you have to put the energy in. Energy, once you took it, is gone. That's what makes the CO2 truly a waste product. That coal, oil, or gas was a carbon form with lots of energy. You took the energy out by sticking an oxygen onto it.

If you want to get the energy back in, you have to take the oxygen back off. That's, in effect, what biology does. One way of closing this cycle ‑‑ this is something we are working on here, with Bruce Rittman and his group ‑‑ is we say, "Algae would like to do photosynthesis. They convert sunlight, CO2, and water into biomass, into storage, into bio‑oils, into energetic carbon compounds." That can be done.

If your algae grow inside a bioreactor, they need CO2, which they cannot take out of the air, even if they are in an open pond. They would like to see more CO2. Either way, we can come along and say, "We collect CO2 out of the atmosphere. We feed it to the algae. The algae now make fuel."

Dr. Biology:  We have an algae farm connected to your apparatus, that actually pulls the CO2 out. You feed the algae. The algae produce the fuel. This sounds great. It means if we get this all working, we have algae farms.

We have your mechanism of feeding them CO2. Sounds like a great idea, the same thing with the solar panels. If this all works, do we need to worry about carbon emissions anymore?

Klaus:  Yes and no. The problem with the surface of the planet is it has a certain amount of carbon, some of it in the ocean, some of it in the air, some of it in the biomass. We come along, and we add to that. There are huge fluxes, by the way.

There's a huge amount of carbon dioxide, going from the ocean into the atmosphere, and back. There's a huge amount every year, which goes into all the leaves in the plants, which then fall back on the floor and rot. Those are big numbers shifting back and forth.

Dr. Biology:  Part of the carbon cycle that...

Klaus:  That's part of the carbon cycle. The total amount of carbon, in the ocean, in the atmosphere, in the biomass, doesn't change. On average, these groups don't change. There's big fluxes in and out. On average, nothing changes.

Now we come along, and we steadily, every year, add carbon dioxide to the atmosphere, which was not in this part. It came from underground, deep underground, where for millions of years, it hasn't been touched.

Dr. Biology:  The balance has been thrown off.

Klaus:  We are constantly throwing the balance off. If you look at it, every year, if you go to Hawaii, every year the CO2 in the atmosphere goes up and down, 6 ppm all by itself.

The reason is every summer all the photosynthesis in the Northern Hemisphere sucks out the CO2. Every winter, respiration wins, and it all comes back into the atmosphere. If we weren't around, every year there's this saw tooth, peak to peak, there's a 6 ppm every year.

Dr. Biology:  It's just that that peak, that band, is shifting.

Klaus:  Now the band is shifting. It used to shift by 1 ppm a year, then by 1.5 ppm a year, then by 2 ppm a year, and now it's 2.2 ppm a year. That's us adding new carbon into the system, which simply wasn't there before. We are changing the balance.

My argument is, for every ton of carbon coming out of the ground, another ton has to back in. You still need air capture, because for every ton of CO2 going into the air, another ton has to come out.

You could do this biologically. You could grow trees, but then the amounts we are talking about look like more than all the world's agriculture. That's your challenge, but you need to balance that part.

The other part you balance is, we will end up at 400, 500, 600 ppm, wherever we manage to stop. What do we do with what we already have done? If you had had this conversation in 1980, I would have said, "Look, you need to stop. That's the end of the story."

Now, I'm going to tell you, "We are now at 400 ppm. Realistically, you are not going to stop before 450 ppm."

Dr. Biology:  It's like a giant train.

Klaus:  It's a giant train.

Dr. Biology:  You can't stop it right away. It doesn't stop on a dime.

Klaus:  As a matter of fact, if you could do magic, and from here on out, every new power plant we built, every new car we buy, all of the things we have, will stop producing CO2.

All the old equipment is going to run out its natural life. You end up putting more CO2 into the atmosphere than we can tolerate.

I think we have possibly already created a debt large enough, that we will have to deal with it. We have to pull the CO2 back, in order to come back down.

Dr. Biology:  Not just stopping, because the train's moving on. We're going to go beyond where we are now, no matter what. Now, we have to have a mechanism to reverse it, basically. All the work you're doing on that will help with that process.

We have a mechanism of bringing it out of the air. We have a mechanism to turning it into fuel, which is the algae farms, which is one possibility and then, as you said, the solar panels.

Is there something that a person should still be doing today? If we want to slow the train down, we all have to be part of the process. If we don't work on slowing the train down, you're going to have a whole lot more work, trying to put it back in balance.

Klaus:  It's worse than that. People have said any capture is sort of nefarious, because it allows the excuse, "We don't need to do anything now. We can solve the problem later." I disagree with that.

The reason I disagree is, yes, a little bit it's true, but in a way we're already too late. If we keep going too far, we will do damage we cannot undo.

We can get the atmosphere back to, let's say, 400 or 350 ppm. If the glaciers melted in the meantime, they won't freeze overnight, just because we decided to do this. There are real damages we create, by letting this thing go too far.

The more you slow down now, the more you manage to solve the problem right away, the less damage you will do.

I would argue another point, why air capture is actually helpful in this discussion. Think about it this way. The air capture differs from every other way of getting CO2 back, in that it doesn't really need the direct cooperation of the polluter.

If we come along and say, "We can do air capture at an affordable price." Right now the coal plant operator can say, "Look, we understand there's climate change. We understand it's not a good thing. We also know that you need energy, and you need to be able to afford it.

"It's going to be so horribly expensive, that you don't even want us to do this. We keep researching the problem, but we can't really introduce it yet."

If on the other hand, you have air capture, we can say, "OK, you don't have to cooperate. We will just do it, and all you have to do is pay the bill." You'd be surprised how fast they figure out how they can deal with the CO2 from the smokestack more cheaply than taking it out of the atmosphere.

The other thing we're after is the CO2 which has already been put out. That could be, by far, our biggest application. We will have to come back.

If we come back by 100 ppm, which I think is quite likely, we will have to find a place to store CO2, a disposal site, if you wish, or disposal sites, big enough to accommodate more CO2 than the world emitted between 1900 and 2000.

Dr. Biology:  Where are we going to put it all?

Klaus:  That, to me, is one of the biggest questions. Where do we put it? That's why I'm so keen on developing mineral sequestration, where you take rocks, which really respond to acid, and then form salts.

We can make a mountain of that stuff, and put it away. In the end, you make mountains, but we also have mined mountains of coal, and we have mined mountains of dirt, over the coal, which we had to put aside. It turns out those mountains are bigger than the mountains we will make, when we make carbonates.

Dr. Biology:  You've been talking a lot about balance. Let's go through the details. In particular, quickly, what is it when we talk about balance that you're looking for?

Klaus:  The atmosphere, the biosphere, and the ocean, have a balanced carbon budget, which takes literally hundreds of thousands of years to change. Therefore, as long as we keep adding into this box, we have to subtract the same amount.

For every ton of carbon coming out of the ground, another one has to go back. For every ton of CO2 we put in the atmosphere, we have to figure out how to get one back out.

With those two rules, you are forced into thinking about the problem, in a balanced budget kind of approach.

Dr. Biology:  From a biological standpoint, we always talk about equilibrium, that steady state, where things work optimal. Our bodies are always looking for an equilibrium. We want to have a constant temperature within a very few degrees.

You know what happens when your body temperature rises too high. You end up feeling very sick. It can't go very far. Actually, it can be very deadly.

The whole biosphere is basically a living organism. We want to make sure that we deal with that equilibrium.

Klaus:  By technical means, we bring it out of balance. Therefore, technical means can help us getting it back into balance.

Dr. Biology:  Tell me, you said you have some experiments running in the desert now?

Klaus:  We have a small device, which has been collecting CO2 since September, not in large quantities. Our main goal was to figure out how sensitive are we to the weather. Keep in mind, we are moisture‑sensitive. We love when it's dry. We don't work so well when it's raining.

Dr. Biology:  How soon would you predict ‑‑ this is the optimistic view ‑‑ having these in large‑scale production, these scrubbers?

Klaus:  Once you have the will to do it, the economic structure's in place, that actually people can make profit on it. You give it a couple decades, and it moves from being a small thing, to being fully established.

Dr. Biology:  Your prediction would be twenty years.

Klaus:  My prediction is there will be a latency time, which has to do with how fast we can convince the world that it's necessary. At the end of that latency time, to go from practically nothing, to being full scale, is on the order of two decades. Keep in mind, you haven't solved the problem yet.

At the end of the two decades, you have a fleet in place, which can pull the CO2 down. I have a hard time believing that that fleet will be much larger in its capacity than what we emit today.

Dr. Biology:  We want to make sure that we reduce, right now, so that when we get to the 20 to 50 years, that we actually have less work to do, and we have less damage that has occurred. That part is something that even if you fix the atmosphere, it's not something you can fix overnight.

It's important as an individual to figure out how to reduce your carbon footprint. At the same time, we work on this mechanism. The shining light at the end is that there is a potential to pull the CO2 back out. That's the key to me.

Klaus:  We could start it right away. If I could make regulations, I would say, "There's a very simple rule. If you want to dig up a ton of carbon, you show me a ton of carbon which has been put away." The moment you do that, I think air capture will become important.

Dr. Biology:  On Ask a Biologist, I always ask three questions of my scientists. We'll start with the first one. When did you first know you wanted it to be a scientist?

Klaus:  In high school. I think when I had physics classes, I got really excited about this and really interested. And then, at that point, I knew I wanted to study physics, which I ended up doing.

Dr. Biology:  Now, I'm going to do something that it's usually harder for my guests. I'm taking everything away. You can't be a scientist, you're at a university, so I'll take away teaching because I know a lot of my guests have tried to slide into teaching.

This is where you get to expand. You get to do anything or be in any kind of career. What would you do, or what would you be?

Klaus:  A lot of the things I'm interested in are about systems, and one of the things I realized the world will need is far higher levels of automation. I would be working on automating all sorts of processes, fascinating ones. Self‑driving cars and machinery like that.

I think that also helps in what I'm doing because these machines have to be small and sit in large numbers somewhere, and they better be automated because you couldn't afford the people who do it. I'd be in an industry like that.

Dr. Biology:  For the last question, what advice do you have for a budding young scientist, a young budding ecologist or someone that is really interested in the environment?

Sometimes it's even the person that already had a career, but they always wanted to switch over, you can think of any of those. What advice would you have for them?

Klaus:  I would emphasize the fundamentals. If you understand the systems, understand the underlying basics, that most of these things also means math, chemistry and physics, and biology. If you understand those things, you can do a lot of things.

Learning what is today hard, may be fun, but it turns out by the time you finished, it's last year's news. If you know the basics, you can get into the next big thing much more easily than if you were an expert of the last big thing.

Dr. Biology:  The fundamentals, having a really strong foundation and the ability to learn new things and adapt, that's the piece that you're...

Klaus:  Yes, I gave a convocation speech some time ago to people who had just gotten their PhD and I said, "What you really learned is how to learn."

Dr. Biology:  Well said, well said. With that, Klaus Lackner, thank you very much for visiting with me today.

Klaus:  You're welcome. It was a pleasure.

Dr. Biology:  You've been listening to Ask A Biologist, and my guest has been Klaus Lackner, professor in the School of Sustainable Engineering and the Built Environment in the Ira A. Fulton Schools of Engineering. This is at Arizona State University. And he's also the director of the Center for Negative Carbon Emissions, also at ASU.

For those of you who might want to explore more about his work and the Center, pop on over to

The Ask A Biologist broadcast is produced on the campus of the Arizona State University and is recorded in the Grassroots Studio, housed in the School of Life Sciences, which is an academic unit of the College of Liberal Arts and Sciences.

Remember, even though our program is not broadcast live, you can still send us your questions about biology using our companion website. The address is Or you can just Google the words, ask a biologist. I'm Dr. Biology.

Transcription by CastingWords

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Hacking Nature

Audio editor: CJ Kazilek

Drawn to Bones

Television portrays the lives and work of forensic artists, but what is it like to really be a forensic artist? Are the tools you see on the big and little screen really used by the people who recreate the face of someone when there might only be a skull or parts of a scull to use as a starting point? Dr. Biology visits with forensic artist and author Catyana Falsetti to learn the answers to these questions and a lot more.

Content Info | Transcript

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Topic Time
What is forensic art and the silent epidemic? 01:24
What started you on the path to be a forensic artist? 03:48
How long have you been a forensic artist? 06:30
What is it that gets you up in the morning? 07:11
If you have DNA, why do we need forensic artists?  08:14
What are some of the tools you use? 10:03
Tissue Depth Measurements 11:33
More on tools of the trade - digital tools 13:45
What is your preferred tool? 15:13
Do you use color in your work? 15:46
Is there a reason to avoid color? 16:35
What are the most common traits of a human head? 18:05
How do you know their skin color? 20:03
Does the skull indicate symmetry? 20:37
How long does it take to do a reconstruction? 22:09
Bones counterpart - Angela 23:01
Three questions 25:10
When did you know you wanted to be a forensic artist? 25:24
What would you be if you were not a forensic artist? 26:21
Advice for someone wanting to be a forensic artist. 28:16
Sign-off 29:01

Transcript - (PDF)

Dr. Biology:  This is "Ask a biologist," a program about the living world, and I'm Dr. Biology.

While we often look at science and art as two different worlds, they are actually closely linked. For instance, you need to be both creative in both science and art, at least if you want to be successful.

If you think about it, we design buildings, and we design experiments. Both science and art include communication as part of their focus. If you take some time, you are likely to find even more ways science and art really are kindred spirits.

But one career that clearly shows how these two worlds are really one is the forensic artists. These are the people who can put a face on a skull of an unknown person. Often their work is the key to solving a crime or mystery that without their skills, talent, and knowledge might be left unsolved.

My guest today is Catyana Falsetti – a forensic artist who's been helping to identify people for more than 14 years. She and her forensic anthropologist husband, Tony Falsetti, have been involved in a collection of cases and mysteries. When we'll get to go back to, I hope, in this show, with our guest.

Welcome to this show Catyana Falsetti and thank you so much for joining me.

Catyana Falsetti:  Thank you for having me. It's a pleasure to be here.

Dr. Biology:  Before we delve into your world of the forensic artist, let's talk a little bit about forensic art.

Catyana:  There’re many different types of forensic art. Forensic, just means it's for use in court. Forensic art can be used to indicate any graphics that are used in court. The most commonly seen types of forensic art are composite sketches.

Composite sketches created when an artist sketches down with a witness to help find an unknown suspect. He'll create an image to be put out into the media to help identify that suspect. More accurately, the person would be a composite artist as the majority of composite artists, that's their main focus. They don't necessarily do the other types of forensics art.

Other types of forensic art are age progression. National Center for Missing and Exploited Children does the majority of those. Although, I have training and other people around the country have to had training for age progressions.

Age progression is for children are done when there are abductions or children go missing to make them look older. It can also be for adults for a long term fugitives, like in the case of John List, Frank Bender create an amazing facial reconstruction sculpture.

There are also image clarifications or image enhancements. They're called two different type‑of‑things. We'll take video and then try to enhance that and sometimes create a drawing from those images. Facial reconstructions or, approximations, which is when we'll take skeletal remains of an individual and create a face from that.

If there is enough flesh left on a person, we'll also do what I call a post‑mortem image. If the person has some decomposition or some scars on them, we'll just use that photograph to create an image that can be put out into the media for unidentified individuals. We have over 40,000 unidentified individuals in the country, there is 1,300 in Arizona.

Dr. Biology:  I didn't know that there were that many.

Catyana:  It's called the silent epidemic.

Dr. Biology:  Where did you start that got you on this path to being a forensic artist?

Catyana:  I've always been an artist. I feel like I could probably draw before I could write. My mother always was like, "Here's some paper, go entertain yourself." Coming from a family of artists, that seemed to be the norm. I was always interested in art. I was always interested in history. I liked earth science and biology, found it all very fascinating, origin of human kind.

I always loved museums, loved sculptures, loved looking at sculptures of us, of individuals. Wax museums when they had wax museums, like that was a normal thing. I always wanted to do sculpting, I always wanted to do portraiture. I did my first portrait when I was 12, I think.

I studied fine art at Colorado State University for a year‑and‑a‑half. Then I took my first anthropology course, and had always been fascinated by the origin of human kind. The idea of universal morality, cultures in general, how people developed.

I switched to anthropology and history because it was either you're a creative thinking person, art person, maybe history and English, but certainly not chemistry, biology or physics on the other side. I found that to be very detrimental looking back, looking back, because my grandmother was a pharmacist, a tailor, a oil painter, assuming painter as a well as other creative things and that was normal for her.

She used her creative ability, her spatial thinking for multiple paths and Michelangelo, Leonardo De Vinci, they weren't one or the other because it's all the same.

Dr. Biology:  That's actually something that's very recent in history that we started to separate these out. It's not uncommon you have the engineer, the architect, the artist. It goes on and on and what I found also interesting is the fact that you say you come from a family of artists. Your mother's an artist?

Catyana:  And scientist. I guess my father was an engineer. My grandfather was...his department in the treasury, so he was an accountant, a businessman, then the other side that was teachers. They were English teachers.

Dr. Biology:  There aren't that many forensic artists in the country. I was doing some research and there's a little over 50, possibly out there. While there may be a lot of jobs, it seems like you'd be in demand because there are lots of places that that kind of skill, both the science and the art are important.

Whether it's a cold case, that's more of a crime or as, we'll talk a little bit, in a bit about the world of mysteries, historical mysteries that are fun to deal with. You obviously have found a love of this and have stayed with it. What is it about forensic artist...what is it that gets you up in the morning?

Catyana:  The possibility of helping giving family or individuals the answers to what happened to their loved ones. I have one case, that individual was found in 1975 in Ohio and he was unidentified and buried. In 2012, he was exhumed and then I was asked to do a facial reconstruction.

In that case, I did a clay work construction, there was hair found at the location, so I could use that information and I created a facial reconstruction. It went out on the media and within a day, the niece called in and said that was my uncle. She and her brother both gave DNA samples and he was positively identified.

Dr. Biology:  From 1975?

Catyana:  Mm‑hmm.

Dr. Biology:  Wow.

Catyana:  I got to meet her and her brother, they were very, very thrilled to have those answers.

Dr. Biology:  You mentioned that you were able to positively identify this gentleman with samples from the niece and the nephew, using DNA. If we have DNA, why do we need forensic artists anymore?

Catyana:  Everyone thinks that there's a DNA database out there with everyone's DNA in it. For privacy issues and lots of other reasons, that's not true. The DNA of the individual, the unidentified individual would never have been compared to his niece because she's not in the database.

What having forensic art does is through, which is the first publicly searchable DNA database, that is solely used for the identification of unidentified persons.

Dr. Biology:  You've basically narrowed down the field, since you don't have DNA from everyone, you get the groups that say, "Oh, that looks like my uncle," and then you ask, at that point, "Can we have a DNA sample?" Then you can get that match, which would never be possible otherwise.

Catyana:  You said that better than I did. [laughs] That's what all forensic art is. It's to composite sketches, it's to narrow down the field of possibilities. A composite sketch should never be used for an arrest. Facial reconstructions should never be used as a positive identification.

Dr. Biology:  One tool.

Catyana:  It's just a tool and the step to a positive identification.

Dr. Biology:  Let's talk a little bit about the tools of the trade. What are some of the tools that you use in your job?

Catyana:  Cameras. Cameras are always very important. When I first started doing this, I would either do a drawing and I'd take photographs of the skull, a stand for the skull to put in the correct position, which is called the Frankfort horizontal position, which is thought to be the most natural position of a person's head in the resting position, so a camera, a scale.

Dr. Biology:  So you could make sure you knew measurements?

Catyana:  We need to have a scale, because we're going to be using mathematical formula to do the approximation for the nose and the mouth and that kind of information. Historically, we would put the markers onto the skull. Now, with Photoshop, I do it digitally, generally.

Dr. Biology:  Are the markers only positioning on the skull spatially or are they also giving you the depth?

Catyana:  They give you the depth.

Dr. Biology:  The depth. One of the things I'm learning ‑‑ just because I like doing research on my guests ‑‑ one of the interesting things is you start with the skull. The question is how do you build it up into an actual living, breathing, in the sense of skin and muscles, all that. Part of that is through these measurements that have been done for a long time? People have been studying this?

Catyana:  Yeah, historically, I think the first tissue depth measurements were taken in 1893 by a German anatomist named Wilhelm His. He would take the measurements on cadavers and that was the norm until about 2000 when they started using ultrasound.

Mary Manhein did a big study using ultrasound, which changes the dynamic completely because a corpse is lying down, number one, and then they're also dehydrated. Also, the sample size was relatively small and more recently we've been taking it with ultrasounds, with CT scans.

I've been working on a research project with Terri Simmons‑Ehrhardt in Virginia Commonwealth University. We've been looking at over 300 CT scans of live people and comparing the soft tissue to the facial bones, and just to see how that impacts the assumptions that have been made historically with facial reconstructions, and creating new data for the future for more accuracy.

Dr. Biology:  For example, where is the deepest amount of tissue on a face? Where would you find that?

Catyana:  It'd be in the cheek; I mean the lower cheek, right around the molar.

Dr. Biology:  With the ultrasound, how accurate are those?

Catyana:  They're within 0.2 millimeters. It's very high accuracy compared to the cadaver data, which the first time they would take the measurements, they would take a CT needle, as the article described it. They'd take a needle, put it over a flame to make it black, and then insert it at that point and pull it out and then measure the depth that the soot was gone.

Dr. Biology:  It was good but only as good as the technology of the day. Now, we move fast forward, we have ultrasound, and then we have CT scans, what computer tomography, and that allows us to get some very precise measurements and even better, we have it done on living humans so that we can have a bigger sample size?

Catyana:  Yes.

Dr. Biology:  When we're talking about tools of the trade, we have a camera?

Catyana:  All right. [laughs]

Dr. Biology:  We have Photoshop?

Catyana:  Well historically, we have to have a stand for the skull. We use Duco Cement still to glue the skull together, use cotton balls to imitate any tendons or soft tissue, spacers, as well as clay. We use oil‑based clay, or some artists use water‑based clay, to do the clay reconstructions and now we're moving into 3D software sculpting.

I've been using Blender ( a lot because it's an open source software that's out of the Netherlands. It's really great for educational purposes and sculpting purposes that anyone can use around the world. There's an artist in Brazil that uses Blender exclusively for his facial reconstructions. Other artists use ZBrush more than anything else.

Dr. Biology:  This is sculpting in the virtual world? Does it allow you to try different versions? What ifs? Because that's one of the things that I find the computer allows you to do, to explore much easier than if you're doing an actual clay model. It's a lot more tedious to do and then undo?

Catyana:  Yeah, just like in Photoshop, there is layers that you can make visible or turn off. Once you have the skill‑set of the software, it's easy. [laughs]

Dr. Biology:  What's your preferred tool?

Catyana:  Every artist is taught to draw. That's the baseline. Drawing is enjoyable, sculpting is satisfying, but it can take up to two weeks, if not longer. You're also covering the skull and you can't just use a layer to turn it on and off. Photoshop is the fastest and the easiest so far, and I'm transitioning into the 3D software arena.

Dr. Biology:  Do you use color in your work?

Catyana:  I always provide an image in black and white and we will only do color if there's evidence to back that information up.

Dr. Biology:  What do you mean by that?

Catyana:  If there's hair found at the scene, then I'll take the hair, and I'll clean it off, and I'll make measurements of the hair, take pictures of the hair to try to get the most accurate color, and that's why Photoshop is great is because you can use the eyedropper to get colors.

Also, if there is any clothing found at the scene ‑‑ if there's a shirt with a specific pattern, or a dental implant with a specific pattern on it, we'll use that, or some glasses that are found at the scene, or dental implants, meaning dentures, then we'll use that information in color.

Dr. Biology:  Is there a reason to avoid color?

Catyana:  People's perceptions are varied and some of the population have expectations of images to be exactly accurate. The more ambiguous we can be about the specifics, like a hair style, or a hair color, or a skin tone, the better, because then it makes the audience understand there are possibilities of variance within that image, hopefully.

I had a forensic artist when I first started, he said, "I did this facial reconstruction."

I think it was in Norfolk Virginia. "I used green clay because that's what they had." They had green clay, he did the reconstruction, and then he took it over and showed the grandmother of the person they thought it was. She's like, "Nope, not him."

We took the dental records, they compared the dental records. It looked like it was him. They took the image over to her again and she said "That's not him! His skin wasn't that color." I think that's the first time that the artist started to realize, is that everyone doesn't have the perception of an artist.

Some people can walk into a house and say "Oh, look this would look great in blue with grey drapes, and this..." Other people walk in and say, "I've no idea what you're talking about, I can't even imagine that."

Dr. Biology:  They can't visualize.

Catyana:  So we have to accommodate, or try to accommodate, people that can't [laughs] visualize the color differences.

Dr. Biology:  What are the most common traits of a human head that we key in on this, when we're looking? What are the things we typically see?

Catyana:  Humans generally recognize head shape, first. If you see someone across the room and you think, "Is that my friend?" It's because they kind of have the same body build and gait and head shape, and then...

Dr. Biology:  So long and narrow, or rounded, or...?

Catyana:  Right.

Dr. Biology:  I get it, I get it.

Catyana:  Then different people notice different things but, some people have a very large nose or very big eyes, or a big mouth, and that will stand out more. So I don't know, among the features, it's more the positioning of the features.

The features have to be positioned spatially, in the right place, for them to look more identifiable. There are websites that if you google celebrities, they will put Tom Cruise's eyes close together, or something, and they just look completely different.

And that's the good thing about the skull, is the skull will tell us where the eyes are, where the nose was, and where the mouth was, in relationship to each other.

Now, the studies that we're doing is looking down into more of those details of lip width, and positioning of the nose, in relationship to the nasal aperture and the eyes within the orbits. So they're trying to get even a higher level of accuracy.

Dr. Biology:  So, if you have a long, narrow, nose, or a broad nose, those are things you're going to be able to know more with these databases.

Catyana:  That and where your nostrils are, in the relation to the nasal aperture ‑‑ if it's right over it, if it's five millimeters below it, the width of the nostrils.

Dr. Biology:  One of the things we are getting to talk about, where you said, "Well, I can't put hair color on someone unless I have samples of their hair." The other question is, how do you know their skin color?

Catyana:  Now we're working with DNA profiling and can help more with phenotype, just talking to one of the DNA specialists up at ASU West, and he's going to be helping us with a project.

I said, "Can you help determine what her skin color was," and he said, "Yes, we should be able to."

Dr. Biology:  Right, and so when we get into the genetics, there's genotype and phenotype. With the phenotype, that's actually how we looked on the outside. That would be our hair color, our eye color, skin color.

Is the skull accurate enough, or does it giving enough information to know if someone is very symmetrical? Because that's one of the interesting things. We have a tendency to look for symmetry.

So, really balanced on the eyes, balanced as far as the ears, where they're positioned. You getting clues from that or is it not a good reference?

Catyana:  No, the bones are the starting point for the whole body, so they're very strong indicators of symmetry. Humans, on average, have four millimeters of symmetry or less, and if they have more than that, then it becomes noticeable.

But everyone's asymmetrical, and that can definitely be seen on the skull and...I mean, every nasal aperture I've ever seen is asymmetrical, and so if you start looking at people's nostrils, it will start to really freak you out.

Dr. Biology:  You know, that will be what we'll do from now on, as I'll be looking at everyone's nostrils.

Catyana:  Yes. [laughs]

Dr. Biology:  I'm looking across at your... are your nostrils symmetrical. [laughs]

Catyana:  But that's also an interesting point, is that one reason why people that have had plastic surgery look unnatural is because they look too symmetrical.

Dr. Biology:  Right, too perfect.

Catyana:  Right, which is unnatural. [laughs]

Dr. Biology:  In talking about these reconstructions, you touched a little bit about clay reconstructions can take a couple of weeks. In general, when you used the different techniques, how long does it take to do the reconstruction?

Catyana:  For a Photoshop reconstruction, I can do that within a day or two. The 3D reconstruction will take around two weeks.

Dr. Biology:  OK. And then, old school, you have to first do the clay model, then do the sketch? Can you ever do a sketch easily, without having the clay model?

Catyana:  I would do the sketch first, and you don't need to do a clay model. You do sketch, you can just do a sketch.

Dr. Biology:  Right off the skull itself?

Catyana:  Mm‑hmm.

Dr. Biology:  So the process of that is, again, just taking measurements, very precise, measurements on the skull?

Catyana:  Yes, taking photographs to scale, having those photographs to either draw by hand over it, on a piece of vellum or a tracing paper.

Dr. Biology:  Over the photograph?

Catyana:  Over the photograph that has the markers on it, and the scale.

Dr. Biology:  When talking about the world of computers, we have Photoshop and we have the 3D software that's coming from the Netherlands and we're using now computer tomography, which are CT scans and ultrasound.

I can't help but also think about the television show "Bones."

Catyana:  [laughs]

Dr. Biology:  Yes, I can tell you know where I'm going. So, you have your fictional counterpart out there, who is the forensic artist on the program and...

Catyana:  I have never seen it.

Dr. Biology:  You've never seen it? OK, well, you are Angela Montenegro, just so you know.

Catyana:  [laughs]

Dr. Biology:  And the intriguing thing about that is she comes from a background of artists as well. It's interesting to me, because she has a background, also, in computer science. Because she's built this amazing computer, that does these three dimensional holograms, they call it the Angelatron.

With Hollywood, we always have to think, "OK, this is neat, but it's not necessarily real," but it does seem like you're moving in that directions.

So, is there going to be a Catyanatron, someday down the road?

Catyana:  I don't have a minor in computer science. [laughs]

There are software that are being developed, or that have been and then are being developed, to help create facial reconstructions with varying levels of accuracy and availability and helpfulness. Maybe, but I just feel like it's like computer animation for the movies.

You're always going to need someone with skill behind it to know how to use the tools. So the tools are going to be changing, but to have a creative human mind, cannot be replaced.

Dr. Biology:  No, and when this case, Angela...she uses it, and she's the only one that knows how to use it. Anybody else that tries to get on that machine, or that instrument, it's always a challenge for them to use it.

Let me shift into an area that we do with all my guests on Ask a Biologist, no one gets to get out of here without answering three questions.

And yours will be a little bit unique because you're going to have the science and the arts part. So, the very first one is ‑‑ when did you first know you wanted to be an artist, or a scientist?

And since you have... you do both, where was the, what I call, the "Aha!" moment? Was there an "Aha!" moment that you said, "Oh yes. This is it?"

Catyana:  I started studying forensic art in 1997. The reason I got interested in it was because I actually read a novel, because I always loved murder mystery novels.

I was in Brazil, I think I had two weeks there and I just kept reading through...I read six or seven books in that two weeks. I don't even remember the book, but I remember that there was an anthropologist who did a facial reconstruction to help identify an individual, and I thought, "That's what I want to do."

Dr. Biology:  Now, was it...the course was set?

Catyana:  Yeah.

Dr. Biology:  And how old were you, again?

Catyana:  21.

Dr. Biology:  21? OK. Now, the next question is...I'm going to take all this away from you, so I'm going to have to take away quite a bit. You're not going to be an artist.

Catyana:  I don't think I'd be alive, then. [laughs]

Dr. Biology:  Well, hope we can figure out something there. And I'm going to take away the anthropology side and some of that. If you could be anything, or do anything, what would you be, or what would you do?

Catyana:  I mean, so that excludes writing, too?

Dr. Biology:  No, I think that includes writing. You want to be an author?

Catyana:  Yes, I just finished and published my first novel. It's a murder mystery novel called "Facing Death," and it's digitally published now on Amazon and NOOK and iBooks, and some other platforms. It will be available for print in the next few weeks.

Dr. Biology:  What's the character?

Catyana:  The character is a forensic artist.

Dr. Biology:  What's the first rule of writing? Write what you know.

Catyana:  Yes, and I did. It's the first book in the series and I hope to highlight a lot of the issues with unidentified decedents, as well as some other lesser known important issues that speak to me, like the Japanese internment camps in America, or massacres in Colombia, or the mass deaths in South America, or other places around the world.

I want to highlight and educate people in an entertaining way, as well as educate about forensics in general. This first book I started 13 years ago, and it's kind of a coming of age for a young woman in the forensics field, which, especially at that time, was heavily law enforcement. So, there were fewer women.

Dr. Biology:  What advice would you have for young CSI person, someone that wants to be a forensic artist? What would be your suggestions?

Catyana:  As far as majors go, I would say getting a degree in something like criminal justice or forensics sciences, a major and a minor in fine art. If you're an artist, you should always have strong drawing skills. In addition to that, computer animation skills or computer software skills.

Dr. Biology:  Well, on that note, Catyana Falsetti thank you for being on Ask a Biologist.

Catyana:  Thank you for having me.

Dr. Biology:  You've been listening to Ask a Biologist, and my guest has been forensic artist, Catyana Falsetti. If you'd like to continue to explore the human skeleton, and learn a bit more about bones, leave a fun section on our companion website called "Busy Bones."

Just point your browser to, and you will find a collection of games, simulations and experiments, all focused on bones. If you'd like to catch up on the earlier interview with Tony Falsetti, you can just go to our podcast section and look for "Skeleton Secrets."

The Ask a Biologist's podcast, it's produced on the campus of Arizona State University and is recorded in the grassroots studio, housed in the School of Life Sciences, which is an academic unit at the College of Liberal Arts and Sciences.

And remember, even though our program is not broadcasted live, you can still send us your questions about biology using our companion website. The address is, or you can just google the words, Ask a Biologist.

I'm Dr. Biology.

Transcription by CastingWords

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Drawn to Bones

Audio editor: CJ Kazilek

Seeing DNA

Want to see the tiny instruction set for all living things? Here is an activity that you can do at home or school that will actually let you see DNA.

>> Full Story

Monster DNA

In the tiny world of DNA, we might call genomes monsters. These huge sets of information include all the codes for all the genes present in an organism. From genomes, we can learn about the traits, diseases, and evolution of a species, and that’s just a start. What might such a monster set of data do for us if it was about our very own North American monster – the Gila monster? Computational biologist Melissa Wilson Sayres tells Dr. Biology about the Gila monster, the life-saving venom in its saliva, and what we might learn from the monster genome.

Content Info | Transcript

MP3 download | 15MB

You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialize correctly.

Topic Time
Introduction [DNA Day] 00:00
What is a genome? 01:23
When was the human genome sequence completed? 03:27
The Monster DNA project. 03:54
What is a Gila monster? 04:35
Gila monster genome and the Animal Superpower Challenge. 06:19
Why are we interested in the genome of a Gila monster? 08:15
Gila monster spit. 08:58
Gila monster unique features. 10:43
Loss of Gila monster habitat.. 11:27
The problem with relocating Gila monsters 11:57
How much and often do Gila monsters eat and drink? 13:16
The unusual thing about the Gila monster sex chromosomes 15:01
What do you do with the genome information? 16:53
Who would use information from the Gila monster genome? 18:19
DNA is amazingly efficient for storing information. 18:38
Who is involved with reading the genome? 19:06
What do you do with 400 million tiny pieces of DNA in it? 20:20
The undergraduate researcher. 20:52
Three Questions. 22:14
When did you first know you wanted to be a biologist? 22:23
Did you always like math? 25:12
What would you do if you could not be biologist? 26:44
Advice for future biologists. 28:34
[learn/play - DNA Basics - Decode a Monster Genome - DNA Day]

Transcript - (PDF)

Dr. Biology:  This is "Ask a Biologist," a program about the living world and I'm Dr. Biology. In case you don't have it marked on your calendar, each year, April 25th is designated as International DNA Day. You might be asking "Why do we pick the 25th of April?" Well, it was on that date in 1953 that the structure of DNA was first published in the journal Nature.

By the way DNA stands for Deoxyribonucleic Acid. And I know that seems like a mouthful, but it seems only fitting because after all we're talking about something. It's the blueprint and instruction set for all living things. While the discovery of the structure of DNA was a milestone, learning how it works packages information has been keeping scientists busy ever since.

My guest today is Melissa Wilson Sayres, a computational biologist who holds positions in the School of Life Sciences and the Center for Evolution & Medicine, in The Biodesign Institute at Arizona State University.

Her work revolves around population genetics, biology of sex, and about a half dozen other research interests. For this show, we get to learn about a new project, you could call it a monster of a DNA project. Welcome to the show, Melissa, and thank you for taking time to talk about some of your work.

Melissa Wilson Sayres:  Thank you so much for having me. I can't talk about it enough.

Dr. Biology:  At the beginning of the show, I talked briefly about DNA, which is Deoxyribonucleic Acid, but I didn't use the word genome. Can you give a 60 second introduction ‑‑ and I'll give you a few more seconds if you need it ‑‑ about the genome.

Dr. Melissa:  The genome is what we consider all of the pieces of DNA in our cells. Typically, that's all the DNA that's passed on from genetic parent to genetic offspring. You might wonder why I used the word genetic, and I try to use that to clarify that we can have lots of family relationships.

When we're studying DNA, we're really interested in the person, or the people whose DNA helped make us, but that doesn't invalidate any of the other family relationships that we have.

The genome itself can consist of the genes that we typically hear about, so you might hear about a variant of a gene involved in breast cancer risk, or a variant of a gene involved in, typically it's in cancer risk or in other disease risk.

There's lots of pieces of our DNA in between those genes that are involved in regulating when and where those genes are turned on. For example, every cell in our body starts out having the same DNA, but my eyes don't look the same as my toes.

The reason for that is that there's the timing and the amount of genes is different in my eyes and in my toes. In addition to those pieces of DNA that regulate when and where genes are turned on, there's a lot of stuff in between that's, kind of, space filler.

Some of it is parasitic elements that are taking up parts of our DNA. Some of it are genes that were around but died. Some of them are regions that we're still trying to understand what they do. That's kind of the most interesting thing to me is that we have this whole space within a very tiny cell and we're trying to understand what everything in that space does.

Dr. Biology:  When you're talking about the human genome this is something that was actually one of the first genomes sequenced, and that's basically figuring all the pieces that are in there. And that was clear back in 2003 and we're still figuring out what we have unraveled. I think the message, when I think about it, is "Wow. There's so much more to learn just in the human genome."

We're going to shift gears just a bit. At the beginning of the show I was talking about a monster DNA project, and that was a little bit of a teaser...

Dr. Melissa:  [laughs]

Dr. Biology:  ...for the audience. Let's talk about your monster DNA or your monster genome project.

Dr. Melissa:  To preface this, I've been studying human DNA and mammal DNA for about 11 years. Although sometimes we might refer to a person as a monster, I've never had the opportunity to study monster DNA and now, being at ASU, I've developed a collaboration with Dr. Dale DeNardo who, for much of his career, has been studying the Gila monster. The Gila monster, I have to say, I've completely fallen for this species. It is incredible.

Typically when I talk to people and I mention the Gila monster I get two responses, either "What is that?" and what it is, is this beautiful black and orange patterned reptile that's not terribly large. Bigger than an anole lizard but smaller than a cat, I would say, and there's a lot of interesting features about it.

The other response I get is "I'm so scared of them. I hope I don't get attacked by a Gila monster." To that I also have to respond that they are not aggressive. Typically, it's said that you have to help yourself get bit by a Gila monster.

They do have a very painful bite and they're described as one of only two venomous lizards but they don't have venom glands in the same way that snakes do or even a venom gland like the platypus, which is wonderful. But their bite, when someone's been bit, it's sometimes described as flaming lava through your veins. [laughs]

So you don't want to get bit but you really have to try to get bit. I've now watched many, many videos on YouTube of people recording Gila monsters, or Gila monster interactions between their cat, or a Bobcat, or a squirrel. The only time I've seen someone get bit is when repeatedly poking at the Gila monster, and going around it.

People say, "Oh, the Gila Monster will bite you if provoked." Well, if you're poking me all the time I might bite you too. [laughs]

Dr. Biology:  Right [laughs] . Let's get into our Gila monster genome. Let me mention, this is part of the Animal Superpower Challenge []. I love that just in itself.

Typically when you do a research, in the past, you would go to NIH, or NSF, or some federal, or maybe large philanthropic granting agency to get funding. You're actually doing crowd funding to sequence the genome of the Gila monster. Let's talk about this.

Dr. Melissa:  There's couple of reasons why. One is that it's actually becoming much more difficult to get funding from these large agencies to do a genome. Genomes aren't the difficult, extremely expensive, extremely time consuming thing that they once were. That doesn't mean that they're cheap, still.

To do a whole high quality Gila monster genome will cost about $30,000. It cost millions of dollars to put together the human genome. In perspective it's much less expensive. It can be difficult to find funding from the traditional agencies for that.

Moreover, one of the things that I've always been passionate about is working with the public, and trying to share the science that we're doing. This is a way that we can have direct buy‑in from the public, on the science that we're doing.

I can answer questions. The way that the particular site we're using,, is setup is that people can ask questions once they've backed the project. About the project, they can share stories that they've had. We can build the community of interest around the Gila monster, its biology, and what we're aiming for is sequencing its genome.

Dr. Biology:  Why would we sequence the genome of the Gila monster? As a species, humans were very...well, what would I've to say?

Dr. Melissa:  Narcissistic [laughs] .

Dr. Biology:  Yes. It's a big word, meaning it's all about us, right? It's all about us. Why are we interested in the genome of a Gila monster?

Dr. Melissa:  There are a few reasons we should be interested in the genome of the Gila monster. For a large portion of the population ‑‑ lizards are scary, and gross. For them, I hope that this project will convince them that, that's not true, of lizards, or snakes and lizards. Particularly not true of the Gila monster.

We're hoping to showcase in particular with the animal super power challenge is that the Gila monster we believe has a super power. That super power is that there's a peptide in its venom, or to be more specific in its saliva, because they don't have the venom glands, in its spit, right?

We're interested in Gila monster spit. There's a peptide there that has been studied for a couple of decades now, and is been used in treatments that are very successful for Type II diabetes. You might wonder Gila monster spit! Well, for some of those people who poked Gila monsters enough, and did happen to get bit, one of the things that was noticed is that their insulin levels would drop when they were bit by the Gila monster.

There was some work trying to figure out what part of that spit was leading to regulating insulin. The challenge is though that we don't know much about the DNA of the genes that are expressed in Gila monster spit.

You can think of spit, and what's composed the saliva in the Gila monster, like other organs. Just like it takes certain genes to get my finger nails different from my nose, it takes different genes to get Gila monster saliva the way it is, and to get that burning lava feel.

With a genome we can start to see how many genes are there. We can look at the sequences of them, maybe which genes are interacting with which. One important part that doesn't often get conveyed when we're studying DNA is that genes don't act by themselves, they act in pathways, they have partners that they co‑regulate with.

Part of what we can do with the Gila monster genome is, is try to infer which genes are working in a group together, that's actually allowing this peptide to be useful in treating Type II diabetes.

There are other things, just in general that are interesting about the Gila monster that are unique to it. It lives in the desert so it's native to Arizona and so some of the things that it does, it stores fat in its tail. It also stores water in its bladder so it can drink a sufficient amount of water and then uptake it later from its bladder which is interesting and weird. But it has these weird, that's me being a mammal, right? Judging something else for doing something in a different way, but I think its physiology is really interesting.

Other reasons you should want to find the Gila monster is it's just this fantastic and unique creature that is specific to our desert environment. It does not live across the United States. One of the things that we're finding is that as people are building their homes, we are encroaching on Gila monster habitats.

There are two challenges. One is that the Gila monsters are going along their typical route trying to find food, trying to survive, and people, who do to misinformation, are afraid of them and are hurting and killing them. Not everyone does, some people will call the Game and Fish Services, and they'll come and take the Gila monsters. But for some reason and we don't understand why, the Gila monsters cannot be re‑homed.

They don't survive if we try to give them a new burrow. I moved from California to here. I grew up in Nebraska. I moved to Pennsylvania. I seem to be doing OK. I can find food, I find shelter. The Gila monsters don't seem to do too well with that. We don't have genetic resources for determining how much genetic diversity there is in Gila monsters. How much is human encroachment of their habitats affecting them.

Not only can we understand a bit more about their role in treating diabetes, we can also generate resources that can be used for conservation of Gila monsters.

Dr. Biology:  I didn't know that you couldn't relocate a Gila monster.

Dr. Melissa:  This is typically what my collaborator, Dale DeNardo, has experienced. He's been able to track Gila monsters, how large their range is, and watching them, and he works closely with Game and Fish and he has several Gila monsters in his lab for that reason. They're fairly sedentary so you can watch them, they kind of, not waddle. I'm not sure the best word to describe how they walk, but waddle is maybe the closest to it.

Dr. Biology:  Especially a full one.

Dr. Melissa:  Yes, a full one. Oh, I didn't mention that another fascinating thing about them is that they can eat a fifth to a third of their body weight in one sitting and they just hork it down. [laughs] It's just like, "Gulp, gulp, gulp." And they typically eat eggs or juvenile mammals, but if they can get one, they'll catch a squirrel or a rabbit and just swallow the whole thing down. Thinking about a third of your body weight, that would be a 150 pound person eating 50 pounds of food.

Dr. Biology:  Wow.

Dr. Biology:  Let's get back to our genome. The human genome project took 13 years. As you mentioned, millions of millions of dollars and lots of scientists around the world. You said that it's going to be around $30,000 to sequence the genome of the Gila monster. How long is it going to take?

Dr. Melissa:  We anticipate it to take less than a year. That $30,000 does not include the cost of people to analyze it. We have that part covered. This is just to extract the DNA and to chop it up into little pieces and then to sequence it. And then we'll get that information back and we'll assemble it.

That's part of why we're really able to do this with crowdfunding. We're going to get the first third of it done in the crowdfunding. So there's several steps to doing a whole high quality genome, and the first part is scaffolding the genome. One part is we're going to get DNA from three males and three females so we can get a sense of some of the genetic diversity across Gila monsters but also, and I hadn't mentioned this yet, one of the really fascinating things about Gila monsters to me.

This is when  I first got interested in them is that in humans, we have chromosomal sex determination and that is individuals with two X chromosomes typically have ovaries and make eggs and individuals with an X and a Y chromosome typically have testes and make sperm. The X and the Y are very different sizes. The Y chromosome is very small and has lost a lot of genes on it.

We know from doing some painting of the chromosomes, you can take a cell and paint the chromosomes. Gila monsters are just the opposite. Females have a large chromosome and a small degraded chromosome. Males have the two large sex chromosomes. So they have chromosomal sex determination like we do but just opposite.

Part of what's a basic science interest to me is trying to figure out what are the genes and the Gila monster's sex chromosome. Do they have a single regulatory switch like humans do? Or does sex determination occur differently in them? For me, when I said that I studied humans and mammals, a lot of what I study is evolution of sex chromosomes and sex differences. Here, it's also a chance to look at sex differences in a monster.

Dr. Biology:  [laughs] We really do have to say that's one of those names that I know, Dale and most of the people that work with the Gila monsters, wished they didn't have the monster tagged to them because it really is unfair. I've spent a fair amount of time with him just because I've had Dale on the show as well.

I think they're, in many ways, cute. They're very interesting because they're different.

Dr. Melissa:  They squat and they have little chubby tails, and they could be a dragon, they could be a teddy bear monster, right?

Dr. Biology:  A good dragon. [laughs] What do you do with the information that you get from sequencing a genome? Where does it go, the information? What do scientists do with it?

Dr. Melissa:  One of the things that we want to be absolutely clear about is that when we get the genome sequence, this will be publicly available. Anyone, anywhere will be able to download and look at the Gila monster genome. One of the first things that we do is we compare it to the genomes of different species that we have.

For example, to illustrate why we do this is if I said, "I want you to tell me about humans." Then I just gave you one human and I said, "Tell me, tell me about humans." Well, it's not very useful unless you have something to compare it against.

With the Gila monster, we're both going to compare against different Gila monster individuals, and we'll also compare against different species so we can see which parts of the Gila monster DNA are very conserved so may be very important. Which parts are changing very quickly in the Gila monster and so maybe part of what makes the Gila monsters so unique with its saliva, with its pattern, with its fat storage, with its bladder storing water.

By comparing against other species, we can see both what's unique and what's shared across those species.

Dr. Biology:  So this leads me into who would use this information so I could see drug companies? Obviously, for medical purposes. As you mentioned, conservation could give us the key to why maybe they're not easy to relocate. The interesting thing to me about it is that when we talk about DNA as you mentioned, it's inside all these cells, and it's packaged in such a way that it's extremely efficient because it has a lot of information in it.

It takes a while to learn what that information is there. It's just like giving someone a huge library. Just because you have the library doesn't mean you understand it because you have to read it and into some cases you had to understand the language.

Dr. Melissa:  Yes.

Dr. Biology:  Who's involved with this? Who's going to be doing this work? It's you and Dale but I suspect there's more.

Dr. Melissa:  For the first stage and you're absolutely right. What we're doing in effect if I can expand on your metaphor is we're building the library and then we're going to let that resource be shared with everyone. For the building that resource part, it's going to be individuals that are working with me in the lab.

We have postdoctoral researchers, the people who have a PhD and are gaining extra training. We have people who are in graduate school right now. There's both master students and incoming PhD student.

One of the things that I'm most excited about is that we have a lot of undergraduate students involved in this project. If you are interested you can go to my website and see that I've been really dedicated to training undergraduates both in biology and in computational biology. Gaining the skills that they'll need and that are translatable to any kind of biological research that they'd be interested in.

Part of this project will be training across those different levels in what do you do when you get a file back with 400 million tiny pieces of DNA in it. It's the most complicated puzzle you could think about and nobody's showing you the picture of what you should be putting together.

We're going to work together with them to learn about different pieces of how you put that puzzle together because you take a certain strategy. That's one of the other aspects of the crowdfunding is that it's really allowing us to focus on training students also.

Dr. Biology:  I have to mention that that's one of the things, I think the School of Life Sciences does a really good job and by design. Undergraduates who come to ASU that want to get into the world of science, you don't just study it, you do it.

Dr. Melissa:  Yes. That's one of the things I noticed in my lab and many other research labs here. Doing research as an undergraduate at ASU is not just washing glassware, it's not just by osmosis being around other people. You're involved in the projects and that is both incredible and sometime frustrating because science doesn't always give us exactly what we're looking for. We can run into walls and challenges.

To me that's the most important part of undergraduate training here is that we work together so they're not struggling by themselves. We're struggling as a group together to try to figure out what the challenges are, or how we can overcome them and really make them the students prepared and integrated.

I don't in my lab consider there to be a hierarchy. There are people who have training and expertise in certain skills and they help with training other people who need to learn those skills but the people with the expertise maybe a sophomore who's already been working in the lab for a year‑and‑a‑half or they maybe the postop that's coming in. We work together really as a team.

Dr. Biology:  I want to shift in to a part of the show that I do with all my scientists. I have three questions. We'll jump into them. When did you first know you wanted to be a scientist? Was there an, aha moment?

Dr. Melissa:  No. There was no aha moment. I have always liked the natural world around me. Maybe the moment was realizing what it was that I wanted to do in science but I always thought that science was interesting. In particular I was actually interested in mathematics. I majored in mathematics as an undergraduate.

What got me to switch into my particular area was that I did a research experience for undergraduates at the University of Nebraska Lincoln in the math department there where we worked on mathematical biology. We used systems of differential equations to model tumor growth and how we might be able to treat it.

I suppose seeing how useful computation in mathematics was to biology and that we could make real meaningful differences in biology by using computation and mathematics. That really turned the tide for me about where I was thinking of going.

I applied to graduate school in the math department and in a biology department that had a bioinformatics program. I ended up obviously choosing the bioinformatics program. What was really interesting about that program is that it allowed me the opportunity to do rotations with different people.

As a math major I didn't do experimental biology research. I had taken genetics. I had taken a couple biology classes but I were one...I was amazed they let me in because it was a computational biology program and I had training in neither biology nor computation to the level that my peers did. I recognize now why because in science it's really useful to have a diversity of opinions.

Although I felt a little bit like I didn't belong, I do hope that I was able to contribute to things in a way that was meaningful. While I was there I first learned about yeast and it smelled wonderful in the lab like bread every day that we would go in and in growing the yeast and doing different experiments with them.

I did a rotation working with the Arabidopsis, this mustard weed. My third rotation was in genetics of sex chromosomes and I found myself staying up at night reading extra papers, trying to absorb everything that I could and realizing there were more questions than answers in my head. I still find myself feeling that way every day that there's more things that I want to know about that field.

Dr. Biology:  Did you always like math?

Dr. Melissa:  Yes I always loved math.

Dr. Biology:  You're always good at it?

Dr. Melissa:  I suppose I always did well. I get these questions sometimes and it's challenging to me because I'm not a math‑wiz so chess I'm terrible at chess. I always tried to like chess because I felt like if you're good at math you should be good at chess. I don't know why I had that perception.

I never felt like a math‑wiz but because I liked math and I had parents who encouraged me to do the thing that I liked, I stuck with it but I never felt I was really excellent at it. I have peers who I took classes with who I could see it clicked for them and everything was quick and easy all of the time.

It wasn't easy to me but it was fun and I suppose I feel very lucky that I had teachers and family who supported me in doing the things that I found was fun instead of what I...I get most frustrated with this one. I'm a parent now and I see other parents say "Oh math is hard, you don't worry about it. Math is hard for everybody. Just try to get through it" but being hard doesn't mean it still can't be fun.

I guess it's why I hesitate a little bit with that because I never felt like it came especially easy to me but it was like solving problems. It was like doing puzzles and I thought that was fun and so it wasn't easy but I wanted to do more of them.

Dr. Biology:  Now I'm going to take it all away. We got down this path.

Dr. Melissa:  [laughs]

Dr. Biology:  I'm going to take all the things you've been doing. You can't be a scientist, I'm going to take...the mathematics is going to go away. I'm going to take away teaching because I know you'd love to teach. This is an exercise and stretching. What would you do and what would you be if you could do anything or be anything?

Dr. Melissa:  If I can't do the things that I'm doing now, I would be an artist. I love sketching and drawing and painting and I appreciate how much work and passion goes into that as much as any field. I used to keep sketched books. I used to think about just doing art all of the time. Maybe that's not so strange. There's a lot of creativity in science as there is in art.

Some of the people I find that like doing science the most also they like thinking about different ways of doing it trying to see the question from a different angle. In similar ways artists often have their unique view of life and of reality. There's no one view of that that is exactly correct.

We get to interpret it in different ways. I'm always an off artist and really try to support them because what artists are doing is fundamentally creating new information in the same way that scientists are creating new information.

Dr. Biology:  To add to that is we design experiments. We use the word design for a reason. Having the ability to approach a problem from different angles as you said is very important for the artist and the scientist.

Dr. Melissa:  Maybe I skirted your...”you can't do the things you're already doing.” But, I still want to be a creator.

Dr. Biology:  The last question, what advice would you have for a young scientist or perhaps someone who's been doing another career and realize that they really love mathematics or they love biology and they want to switch?

Dr. Melissa:  You can do it. I say I'm a little caught off guard by that question. One of the challenges to getting in science is thinking that the people who are doing it already have everything mastered. We are not masters. There is this concept that the more you learn the less you know because you're recognizing how much out there there's still to discover.

For anyone who is trying to get into science, there will always be things you don't know because there's always things that none of us know. Every now and then there's going to be people that you come across that will judge you for your background or for what you know or don't know.

Maybe the best advice is to realize that getting into science, science is no different than any other field in that sense that there are people who will be supportive of you, there are people who have big egos, there are prejudices that exist in science that it's not sheltered. We are humans doing science and you are human who can do science also and you are welcome.

Dr. Biology:  On that note, Melissa Wilson Sayres thank you for visiting with me today.

Dr. Melissa:  Thank you so much for having me.

Dr. Biology:  You've been listening to Ask a Biologist and my guest has been Melissa Wilson Sayres, a computational biologist who holds positions in the School of Life Sciences and the Center for Evolution & Medicine in The Biodesign Institute at Arizona State University.

To like to know more about the animal superpower challenge, you can point your browser to‑superpower. We also have a link on the companion website for the show along with the few other links to learn more about DNA.

The Ask a Biologist podcast is produced on the campus of Arizona State University and is recorded in the grassroots studio house in the School of Life Sciences, which is an academic unit of the College of Liberal Arts and Sciences.

Remember, even though our program is not broadcast live you can still send us your questions about biology using our companion website. The address is or you can just Google the words "ask a biologist." I'm Dr. Biology.

Transcription by CastingWords

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Monster DNA

Audio editor: CJ Kazilek

Ocean Winds and Climate

Did you know the westerly winds in the Southern Ocean have been helping to keep our planet livable? Yes, they have been responsible for soaking up half of the human-made carbon dioxide (CO2) along with a whole lot of excess heat. Dr. Biology has the opportunity to talk with geoscientist Joellen Russell about the research she and a group of scientists have been doing in the southern hemisphere that tells us how important these winds and the oceans are for regulating the temperature of the planet.

Content Info | Transcript

MP3 download | 15MB

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Topic Time
Introduction 00:00
A brief introduction of climate versus weather. 00:56
How the westerly winds of the southern hemisphere impact climate. 03:52
What does the ocean store and where? 06:21
What would happen if we put the heat stored in the oceans in the atmosphere? 06:33
How the Antarctic helps Arizona keep its cool. 07:12
Do the oceans have an unlimited capacity to absorb CO2? 09:10
Will oceans keep slowing the rate of global warming? 09:43
Adjusting computer models as we learn more to make them more accurate. 12:06
ERBE (Earth Radiation Budget Experiment) satellite. 14:48
The story of the tropics and weather. [Hadley Cells] 16:07
Hadley Cells and their effect on the tropics and deserts. 18:33
The plumbing of our atmosphere. 18:51
How oceanographers can live and the desert and still study the oceans. 19:34
Looking into the future using climate models. 22:05
Testing computer models by going back in time. 23:20
Three Questions. 23:04
When did you first know you wanted to be a scientist? 24:37
What would you do if you could not be scientist? 26:09
Advice for future scientists. 27:23
Sign-off. [learn more - SOCCOM] 29:19

Transcript - (PDF)

[Wind blowing the background]

Dr. Biology:  This is "Ask A Biologist," a program about the living world. I'm Dr. Biology. The winds of change are here. We could say the winds are changing the world. In this case, we're talking about the westerly winds in the ocean and the southern hemisphere.

How these two play an important role in our climate is the topic of today's show. My guest is professor Joellen Russell, a geoscientist at the University of Arizona, Department of Geosciences.

While it might seem odd to have a scientist studying the winds in the ocean of the southern hemisphere, based in the desert southwest in the US, we will soon learn that technology makes it possible to study parts of our planet from almost anywhere, including your classroom or home.

Welcome to the show, Joellen Russell and thank you for taking time to talk about your work.

Joellen Russell:  Happy to be here. Thank you.

Dr. Biology:  To get us started today, how about we talk about climate change, because there are some misconceptions about what we mean by climate and what we mean by weather.

Joellen:  Sure. We know that every year, because of the tilt in the planet and the way that it spins, that we have seasons. We have a summer and we have a winter, and that every summer it's going to get hot, and we have some monsoon rain.

Every winter, it's going to get cold and we may have some winter westerly rain coming off the Pacific. That's off California. We know that this happens every year because the planet rotates around the sun, and we have a little tilt. That means sometimes we're leaning towards the sun and sometimes we're leaning away from the sun.

Every year we do this, and every year we have a few storms. Now, the storm part, we can expect. The climate that we expect, usually is three to five storms every winter.

What we see is that over time, with this big change of the amount of carbon dioxide ‑‑ which is one of these what we call greenhouse gases which tends to trap some of the sun that comes into the earth's atmosphere ‑‑ which would normally go back out to space. Instead, a fraction of that stays within the earth's atmosphere.

Because it's just like your down sleeping bag. If you go camping and you have one of those really thin sleeping bags, if it's cold outside, you're going to be really cold. But if your bag is one of those nice, thick, puffy bags with lots and lots of loft in it, you're going to stay nice and toasty. That's like the earth and its atmosphere.

The atmosphere keeps us nice and toasty. The more CO2 and water vapor in the atmosphere, the more you're likely to stay nice and warm. What we see is that over time, we're still going to have seasons exactly like we always do, and we're going to have storms associated with these. That are the weather that we expect.

But you're also going to see ‑‑ because it's getting warmer and warmer, that CO2 is trapping more and more of this heat ‑‑ essentially that numbers of record warm temperatures broken every year is going to go up a little bit.

That is not significantly going to affect how many storms we get unless we see a little bit of reorganization of the plumbing of the atmosphere where maybe the storms don't dip as far south to us anymore. But generally, over many years, over tens and tens of years that we expect there to be fewer days of snow and more days of rain.

Dr. Biology:  Whether you're talking about if you're in Arizona. But as you look around the planet, the seasons are a little bit different.

Joellen:  Absolutely.

Dr. Biology:  Instead of having a summer, winter, spring, and fall. If you live around the equator for example. You might have a wet and dry season.

Joellen:  That's right.

Dr. Biology:  But still impacted by the slight tilt of the earth.

Joellen:  Right.

Dr. Biology:  The other analogy we've used is the climate where you live will determine if you own an umbrella.

Joellen:  Yeah. [laughs] That's a great way to put it.

Dr. Biology:  The weather on the other hand, determines if you're going to take your umbrella with you on a particular day.

Joellen:  That's a very good way to put it. I hadn't thought of it like that.

Dr. Biology:  Let's get back to weather and wind and the ocean.

Joellen:  Absolutely.

Dr. Biology:  Your work is with the wind and the ocean.

Joellen:  It is.

Dr. Biology:  And not just any wind, your work is in the southern hemisphere of the ocean.

Joellen:  Yeah.

Dr. Biology:  Down by the Antarctic.

Joellen:  Absolutely.

Dr. Biology:  And you have a very interesting story to tell.

Joellen:  I do. I think we're seeing and we have two ways of doing it. We have observations where we go down in ships and I used to do a lot of this and I've shifted towards more big computer models. But I used to go out to sea and actually make lots of measurements and I thought I knew what wind felt like. I thought I knew because I'd been in some blizzards before in the northern hemisphere.

But the westerly winds are much stronger in the southern hemisphere about 30 percent stronger. They are enormous winds that blow constantly and have big storms riding along with them. Intensification and then in between the storms you think it'll get all calm. But it doesn't. It just a little bit less roar and what this does is because they roar round and around and around these big winds around Antarctica.

They push the water away from Antarctica. Because there's a little bit of tendency for the water to move away from Antarctica when you're pushing along with these really big winds in the Coriolis force. I'm not going to explain the full Coriolis force but it's related to the rotation of the planet and so pulls the water at the surface away from Antarctica. Because you can't have a hole in the ocean, it upwells.

It doesn't just upwell from the very surface layer, it upwells from the deepest, deepest black abyss from 2,000 meters deep which is roughly 20 football fields down into the ocean. Because you've push the surface away and essentially when you push it away it fills in from this water below. When it comes up, that water has never seen our atmosphere.

The atmosphere that we've put all these fossil fuel emissions into, that has all this carbon dioxide and all this extra heat. It's never seen this atmosphere before. Because it might have gone back down, 200, 300 even 1,000 years before.

When it comes up to the surface, it's very cold and it's full of CO2. But it's got much capacity to even have more because of this excess in the atmosphere that we put in from burning coal and lots of fossil fuels.

It comes up to the surface and it absorbs CO2 and it absorbs heat and then it sinks. Because even though it's absorbed a little heat, it's still very dense, very cold water and it sinks back down carrying the heat and the carbon with it. When it carries that heat and carbon down, it's essentially storing it away from the atmosphere.

If we had all the heat that we have added to the ocean over the last 50 years, if we put it all in the atmosphere, we would be 100 degrees hotter. It's not a little bit of heat. It's a lot of heat. Basically more than 90 percent ‑‑ more in the 9 out of 10 of the total amount of heat that we've grown in our atmosphere ‑‑ is in the ocean.

Only a small fraction like three percent, three pennies out of a buck are actually in the atmosphere.

Dr. Biology:  So it's kind of a heat sink.

Joellen:  It is. It's a huge heat sink and carbon dioxide sink as well. It doesn't just take up the heat, it takes up some of the things that helps trap the heat the CO2, which means that although we're going to continue to warm, we don't warm as much as we would have. I like to give this public outreach talk called, "How the Antarctic helps Arizona keep its cool" which is actually true.

It turns out that one of the things that is most important to understanding how much warmer it might be in Tucson or in Phoenix in the next 20 years, 30 years, is how much heat the ocean continues to take up. Because remember, let's go back to the first part, how does that water upwell? It upwells because the wind is pushing the water away from Antarctica.

We think that the winds have actually intensified gotten stronger and moved towards Antarctica because ‑‑ and you're not going to believe this ‑‑ the ozone hole. I know, everybody talks about global warming as just being the main driver of the changing in the plumbing of the atmosphere in the ocean. But fact in this case it's the ozone hole.

The ozone hole over Antarctica as really big. Everybody knows this, and we know that it's manmade. Because we made all these refrigerant molecules called Freon's or chlorofluorocarbons that helped us keep our refrigerators and air conditioners running. They had to be these gases that were very long lived. So that they would last a long time in our AC's and our refrigerators.

They leaked and they escaped and they went into the stratosphere basically and created an ozone hole, because the chlorine left from the chlorofluorocarbons. That destroyed the ozone. When the ozone was destroyed, it made the upper atmosphere very, very cold. Because it turns out that the same way that the ozone saved us from skin cancer ‑‑ a photon from the sun would hit a molecule of ozone.

The ozone would break apart saving us from that UV that would have given us skin cancer ‑‑ ultraviolet radiation that would have given a skin cancer. Hit the ozone molecule, broke apart. When it reforms, it actually releases heat. It's an exothermic reaction, which is amazing. That's how the ozone used to keep our stratosphere warm.

Without the ozone anymore, the stratosphere started to cool. It's now seven degrees colder over Antarctica up high in the atmosphere than it was 30 years ago.

Dr. Biology:  You were talking about how oceans work as a heat sink. Do they have an unlimited capacity?

Joellen:  They're always going to take heat as long as the atmosphere is warming. If we stopped emitting so much CO2, it started to come down the total concentration, then eventually the oceans would actually be releasing heat rather than taking it up. Because the atmosphere would cool and it would release a little bit as it goes.

But as long as we increase our CO2 in the atmosphere, we're going to increase their capacity ‑‑ the ocean will continue to warm.

Dr. Biology:  Will the oceans keep slowing the rate of global warming?

Joellen:  There are two thresholds that I worry about. The first one isn't actually not the Southern Ocean. The first one is the North Atlantic. Where if we put enough warm water into the North Atlantic and the winds are not strong enough to remove enough freshwater and enough heat to make it cold and salty and sink then we would significantly reduce the amount of CO2 and heat that would go in the North Atlantic.

I would expect that to happen first. The second thing that will happen if we continue to accelerate our warming with accelerated CO2. What I'd expect is that in the Southern Ocean at some point the thick layer of warm water that forms in the summer ‑‑ when the winds are weaker and the warming is most intense.

I would expect, if that layer got thick enough that the total wind energy that we have to expose it to, to mix it away and mix it down. If it's not enough when energy anymore, we will cap the southern ocean deep sink. That would mean that, it basically just sit on it like a lid. All that warm water and if the winds aren't strong enough to break through and that could happen in the future. Probably not soon, but say 30, 40, 50 years.

At that point, we would see abrupt warming in the atmosphere. Both cases but particularly in the southern hemisphere case where so much of the heat is going.

The sink in the northern hemisphere is big but it's not like the Southern Ocean. The Southern Ocean is more than two‑thirds of the total sink. It's more than 68 percent of all of the ocean heat uptake is in the Southern Ocean.

If that ever happens, we will see the rate of warming in the atmosphere increase significantly. Because then it won't be able to reach all that deep ocean cold water ‑‑ be like making the capacity of the ocean much smaller.

Dr. Biology:  As part of this program we talk about certain topics, like say climate change. We know there are skeptics. But before you come to any conclusion, you need to investigate the research and look at quality data.

Joellen:  Absolutely.

Dr. Biology:  This is something that scientists live by.

Joellen:  We test our hypotheses with real observations.

Dr. Biology:  Yes, and there is a possibility that we could change our predictions based on our observations.

Joellen:  We revise our hypotheses if they're shown to be wrong.

Dr. Biology:  Right, so for example the models ‑‑ by the way we're not talking about fashion runway models. These models, which were done on computers, predicted a much faster rate of air temperature warming than we've seen. But it appears that it was because they didn't account for the impact of the oceans.

Joellen:  That is very likely to be true. Partly because we weren't getting our winds quite in the right places, over the Antarctic in the Southern Ocean there, partly because the oceans weren't mixing properly ‑‑ when you did stir them with this extra wind energy ‑‑ and partly because we didn't know. I'll just say this, in 1998, we still thought that it was the difference in the temperature between the equator ‑‑ the tropics ‑‑ and the poles.

We thought it was that difference that mattered to how strong the winds were. The bigger the difference the bigger the winds. That as we were near the poles, it would actually relax and the winds would weaken and that would mean we wouldn't stir our oceans as much.

But it turns out that because of the ozone hole and that cold, cold temperatures way, way up in the atmosphere, associated with this big hole in the ozone, that in fact the winds have increased. They are stirring the ocean much more strongly than we anticipated. This effect wasn't in some of our early models because they didn't have stratospheres, the upper atmosphere.

They thought they only needed to resolve the big thick weather atmosphere that we live in and not the atmosphere above it, way up high, where the planes fly when they're trying to avoid the weather. That's the stratosphere and that's where the ozone layer is. In fact it turns out that that cooling, way up high, it's also another way to talk to skeptics.

Because many of them believe that it might be due to something, some change in the sun and not to human made influences. But in fact, that's not true at all. Because if it were the sun, then the upper atmosphere and the lower atmosphere would be warming all together. In fact what we see is that the lower atmosphere, where we live, the air temperature is increasing everywhere globally.

In fact, 2015 was the hottest year on record ever on planet Earth that we observed in the last say, at least 100 years.

But in addition to that, the stratosphere is colder than we've ever observed it to be, ever. You know how we make those measurements of crisis with these wonderful weather balloons, right? The weather service in Tucson where I'm at the University of Arizona, they released two balloons a day. They will release one at 4:00 PM and one at 4:00 AM.

This is part of a network globally of these balloons that we released to actually look at the profile of the temperature from the surface all the way up into the stratosphere.

It's amazing how much warmer it's gotten in the lower atmosphere and how much colder in the upper atmosphere, which is absolutely counter to the idea that it could be the sun. Even if the earth's radiation budget experiment with IRB, my favorite set of satellites, which does this really neat experiment where it looks out at the sun.

It's up in the upper atmosphere, in orbit, and it looks out at the sun and in at the top of the atmosphere. It looks at the energy imbalance between what's going in and what's coming out. What IRB tells us is that every single year, the imbalance is bigger. That's because there's more carbon dioxide in the atmosphere every year. Therefore more is trapped every year. We are warmer in the lower atmosphere and we are colder in the upper atmosphere.

All of these different kinds of ways of looking at the atmosphere, at the ocean, at the sun, at the ice and we use all of these different measurements and we test our hypotheses and we test and test and test. We push it as hard as we can. Because each one of us would like to be the scientist who has the breakthrough that shows that everybody was wrong and we were the only one who figured it out.

In fact what we find is that although the nuance we..."I did mine a little better than he did. I found out about this great effect of the winds in the oceans stirring." These are great things but they don't change the main story which is more carbon dioxide in the atmosphere is leading to warmer atmosphere temperatures. We're bracing for the change as we increase our CO2.

Dr. Biology:  We talked about the winds in the ocean in the southern hemisphere. But what happens in the tropics?

Joellen:  Yeah. The westerlies are what we call subtropical to polar phenomenon. They work for about 30 degrees north to 30 degrees south. By the way Tucson is down at 32 degrees north. So you know right about where the boundary is. Between that 30 degrees south of Tucson all the way to the other side of the equator at about 30, what is happening there?

Because this is not the domain of the westerlies anymore. This is the domain of the tropics and the tropics have a really interesting phenomenon. Because of course this is where it's hottest. It's because the sun is coming in most directly from right along the equator. Even with seasonal shifts, we see this very warm water.

Because although we have some continents. We have Africa, we've got pieces of Papua New Guinea, and we've got parts of South America and the Brazilian rain forests. We've got all of these things but most of it's water. What happens ‑‑ and this is amazing, is called the Hadley cell.

The very warm water at the surface, it lifts and you get convection, which is where you're actually getting big clouds. They boil up, boil up, boil up. I'm sure you've all seen this happen during a big thunderstorm or in a summer monsoon. They boil up, boil up and they rain as they go, losing some of that water vapor. Losing, losing it, losing it.

When they finally get up to the top of the atmosphere where they've lost all their water and they have no more energy left and they can't get any higher, they flatten out and they form these anvil clouds. The trick is there's lots of hot water and lots of up, lots of convection. The problem is what goes up must come down and where it comes down it is very, very dry.

Because of course it was cooling as it went up and then when it comes down, it warms as it comes closer and closer to the surface. But of course it's already dropped all its water. As it warms, it gets even drier. Low, low humidity, the kind that makes your nose crack and bleed. Guess where it comes down? It comes down right here in the Sonoran Desert.

Not just the Sonoran desert, it comes down in the Atacama desert, it comes down the Gobi desert, it comes down in the Sahara desert, it comes down in the Simpson desert in Australia. At 30 North and 30 South are what we call the downwelling arms of the Hadley cell and it's where we always find our deserts.

Dr. Biology:  I'm so glad you talked about the Hadley cell because we have a great set of stories on biomes on the Ask A Biologist website. That biomes, rain forest and desert are great to go to because they discuss the Hadley cell. They also include an illustration of how the Hadley cell works.

Joellen:  That's actually the plumbing of our atmosphere. You have the Hadley cell that creates the tropical wet rain belt. The two dry zones where we find our deserts in the northern hemisphere in the deserts in the southern hemisphere. Then just North and South of that, we find our westerly wind rain belts where we see the subtropical rain. The big winds with the big storms and we're talking Seattle, etc.

Dr. Biology:  Let's transition. Since you talked about IRB, and we're talking about satellites and sensors...

Joellen:  Sure, love sensors.

Dr. Biology:  Because your research lab is in the middle of the desert.

Joellen:  Absolutely.

Dr. Biology:  Because we also have an oceanographer who has her lab in the desert, Susanne Neuer.

Joellen:  Terrific oceanographer.

Dr. Biology:  I have two oceanographers in the middle of the desert, studying the ocean. How can this be?

Joellen:  Because almost all oceanographers aren't based in the middle of the ocean. We're based on land. We have to fly to get on our ship, and then, "Chug, chug, chug" out to the middle of the ocean. In addition to that, I'm working on a big project called the "Southern Ocean Carbon and Climate Observations and Modeling," which is doing a combined modeling and observational experiment to look at how much heat and carbon the Southern Ocean is taking up and helping us out here in Arizona.

The big thing is that we're not just using ships, we're using ships to deploy robot floats. These autonomous sensors ‑‑ and that means that we're not controlling them we don't drive them around ‑‑ they float, they drift with the currents, they sit down at about 10 football fields down ‑‑ about a thousand meters down.

Every 5 to 10 days, they drop down to 2,000 meters ‑‑ 20 football fields ‑‑ then they do a full profile, taking measurements all the way up to the surface. They beam all that data back by Iridium satellite and we put it up on the Web within two hours of when it reports back to us.

All of these floats are doing profile, after profile, after profile, all by themselves out in the ocean and reporting all this wonderful data back so that I can be an armchair oceanographer in the middle of Arizona.

Dr. Biology:  Can students get to this?

Joellen:  Absolutely. Welcome, welcome. We have a website called www.soccom, S‑O‑C‑C‑O‑M, .princeton P‑R‑I‑N‑C‑E‑T‑O‑N, .edu. The reason it's at Princeton is because this program is led by Jorge Sarmiento who's a professor at SOCCOM, a dear friend and collaborator of mine.

I'm leading the modeling component and my friend Lynne Talley who's a professor at the Scripps Institution of Oceanography in San Diego is leading the observational component. You can check us out and see the data, access the models, access the new observations from the floats. Come on in, the water's fine. We'd love for you all to take a look.

Just, by the way, some classrooms have adopted some of our floats. We even put little stickers on and we'll sign them for you and send you a video of it being deployed. You can follow it around if you'd really like to, because there's a fantastic science fair science that can be done, classroom science that can be done. Come see the world change in real time.

Dr. Biology:  So you're sharing data in real time and students can come and get it? They can do their own research?

Joellen:  Absolutely. Please come on in. We love this. The more, the merrier.

Dr. Biology:  You mention models again. And already, I said this is not a fashion runway model.

Joellen:  [laughs] No, this is what I tell my kids. I'd say, "Look, momma works with math and super computers and I can see the future. Whooo!" [laughs]

Dr. Biology:  Do they believe you?

Joellen:  Actually, it's almost exactly true. That what we do is we use these basic equations of thermodynamics and motion to describe what the water would do if we did a numerical model of how it mixes. We've coupled these ocean models that have the topography and the amount of water and the energy from the winds and all the rest of it.

We've coupled them to atmospheric models of the weather and climate. Not just that, we've now coupled it to the ocean biology chemistry and the land hydrology and dynamic vegetation. We've fully closed the carbon budget and these are now called our system models. We're looking at the fuller system breathing and moving.

If you want to come in, seriously check us out at because, you can see how we diagnose our models, how we validate these models, how we test them repeatedly. To make sure that we're getting it right. That in fact it looks like the real world so that we can trust these projections.

Dr. Biology:  When you're testing your models, do you go back in time and run the model to see if it matches what really happened?

Joellen:  Absolutely. In fact, a lot of our runs start at 1860 when we just started. But it's even before the Industrial Revolution as we're ramping up all the extra carbon from coal burning ‑‑ actually whale oil and all kinds of stuff, all the way through the present day. Then we make projections of what we think the carbon change will be in the future.

The reason we do this is we assume that we're all going to do aggressive reductions of emissions and we see what the climate would be like if we did that. We tried at the very highest if we pumped it all out, we burn it all, what would that look like. We use an envelope basically to see what the difference in climate might be the low end, the middle and the high end.

All the code is available online. It would probably take a supercomputer but you're welcome to all of it. You can see our diagnostic tools as well. We actually have a Southern Ocean model atlas, you're welcome to see the pictures of what we do. We've actually embedded underneath it all of the code for the analysis as well so welcome, welcome.

You can do all the same work I do. Come on in, the water's fine.

Dr. Biology:  Let's move into a part of the show where I ask all my scientists three questions.

Joellen:  Hit me.

Dr. Biology:  Here we go. When did you first know you wanted to be a scientist?

Joellen:  At leased by 12 because that's when I decided I didn't want to be an astronaut. I definitely wanted to be an oceanographer. But probably before that.

Dr. Biology:  So even at the age of 12. You knew you wanted to be an oceanographer.

Joellen:  Yes. I'd always wanted to be an explorer. I grew up in an Eskimo fishing village 31 miles above the Arctic Circle called Kotzebue. It's actually north of the Bering Straits. My dad worked for the Indian Health Service and he worked at the hospital there. I lived there with my brother, my mom, and my dad and it was wonderful. Great way to grow up.

It meant I wanted to be an explorer and I was certain that people had been everywhere on the land. I had two choices, the ocean or space, and I picked the ocean.

Dr. Biology:  Actually we studied space more than we've studied the ocean.

Joellen:  Yes, that's absolutely true. There really are only about 6,000 PhD level oceanographers in the world out of the seven billion people that live here. That means that those 6,000 people have responsibility to study observe, monitor and predict what happens to 70 percent of the planet's surface, 93 percent of all the human made heat.

Half of all the carbon uptake and something like 30 percent of all the protein consumed by people in the developing world who rely on marine sources for their protein. It's an amazing thing that only 6,000 people out of seven million have such a responsibility. I'm so glad I picked this field and any of you listening should definitely consider it.

Dr. Biology:  Now I'm going to take it all away from you. You can't be a scientist and since you're at a university, I'm going to take away your teaching. This is an exercise that makes you stretch. If you could do anything, or be anyone, what would you do and what would you be?

Joellen:  You're not going to want to hear the answer to this. [laughs] You're going to think I'm nuts but I would probably be a lawyer. When I was young, I thought if they ever threw me out or didn't give me tenure whatever I would become a lawyer because I want to fight. I want to fight for the people and I think that science in the public interest is a vital national importance.

I think that sometimes the EPA doesn't do their job. I think sometimes the federal agencies aren't held to account, forced to do more to protect us. We should be pushing our politicians and pushing our legal system to hold companies, hold the public, hold us all to account to live by the rules that will help make the world a better place for our children and our grandchildren.

It's not right that we will leave it in worse shape than when we entered and I'm going to spend the rest of my life trying hard to leave it in better shape than I found it.

Dr. Biology:  The last question. What advice would you have for a young budding scientist or oceanographer? Perhaps there's a lawyer out there that wants to be an oceanographer?

Joellen:  There are so many opportunities. Many people just don't realize that science fairs have prizes. Science fairs have scholarships. You know there is SARSEF. We're about to have the International Science Fair right here at Arizona State. You can participate in a science fair in kindergarten. Your teachers support you. They can do it as a class, they can do as individuals.

If you're bigger and you want to do career switching, I bet you didn't know that you can go to graduate school. They will give you a fellowship. We'll pay you a stipend and pay your tuition. If you go into STEM, if you go into science, technology, engineering, or math.

In some ways, I know it's a big pay cut. You wouldn't be making much. It's just in a stipend, it's not a real salary. But this is an amazing life and discovery every day as part of your job. It just is irresistible to many people and I'd invite you to start young, do it often, enjoy exploring the world around you and test those hypotheses.

You never know what you could discover. The US is full of tinkerers and dreamers and innovators and I just feel like we should be open to all these things.

Dr. Biology:  What about that lawyer that wants to switch to oceanography?

Joellen:  I don't know. Do lawyers know how to do math? [laughs] Yes. I would say that in many ways advocacy is also ‑‑ and that's what lawyers are advocates. There might be many, many great places they could work. I think of our great A National Resources Defense Fund. There's all kinds of fantastic places that they could put their lawyerly talents to work.

Dr. Biology:  On that note, Joellen Russell, thank you very much for visiting with me today.

Joellen:  I'm delighted. Thank you for having me and I apologize to all the lawyers.

Dr. Biology:  You've been listening to Ask A Biologist and my guest has been, Joellen Russell. A geoscientist at the University of Arizona Department of Geosciences. In case you missed the address earlier in the show, don't forget to visit the Southern Ocean Carbon and Climate Observations and Modeling website.

That's a mouthful but you want to go there so you can learn how the Southern Ocean impacts our climate. The address is S‑O‑C‑C‑O‑M dot P‑R‑I‑N‑C‑E‑T‑O‑N dot E‑D‑U. That's

The Ask A Biologists podcast is produced on the campus of Arizona State University and is recorded in the Grass Roots Studio. Housed in the School of Life Sciences which is an academic unit of the College of Liberal Arts and Sciences.

Remember, even though our program is not broadcast live. You can still send us your questions about biology using our companion website. The address is Or you can just Google the words, Ask A Biologist.

I'm Dr. Biology.

Transcription by CastingWords

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Ocean Winds and Climate

Audio editor: CJ Kazilek

An optical illusion occurs when you the way you see something is different from what the object really is. Optical illusions occur when there is an error in how the brain interprets what the eyes are seeing. In general, there are 3 types of optical illusions.

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