Sustainability Videos & Lecture Series

[Wally Broecker:] Well, it’s a pleasure to be a snowbird and to be [laughter] invited down here once a year for a couple months. Elizabeth, my wife, and I really enjoy it out here, and it’s done wonders for my health. I had a open-heart surgery at the end of December, and at my age of 81, it took a while to recover, but the Arizona sun has done wonders.

Now, Sandra mentioned a meeting that we convened. Larry Krause has his origins program, and last year, we decided that it would be good if we ran one on climate. With the events of the last year, it’s become clear to people that we’ve graduated from CO2 buildup in the atmosphere as being a problem to what all of those who participated in the meeting would agree—it’s an emergency.

Why is it that we’ve changed our view a bit? One reason is that new reserves of oil and natural gas have been found that really puts off well into the future the necessity to go away from fossil fuels, at least for running our automobiles, so that’s one thing.

The other thing is that the availability of fossil fuels is going to greatly delay the implementation of clean energy that doesn’t involve putting CO2 in the air. And we also agreed that putting CO2 in the air was like putting garbage in the streets and putting sewage in our rivers. It’s something we just can’t continue to do. If we’re going to continue to burn fossil fuels, we have to pay for the capture and sequestration of that CO2, and that’s what I’m gonna talk about today.

Now, most of you have seen David Keeling’s long record of CO2 content of the atmosphere on top of extinct volcano Mauna Loa in Hawaii. This record here stops at about 2007 or ’08, so if you extrapolate that curve out to ’13, we’re very close to 400 parts per million now.

We started—in 1850, the CO2 content was—of the atmosphere—was something like 280 parts per million, and now since the industrial revolution has pushed it up, as of 2012, to 400 parts per million. Most of the models that are run to evaluate the climate effects traditionally have run at double CO2. The conclusion from those models is that doubled CO2 will produce a warming of somewhere between three and a half degrees.

Now, of course that’s uncertain because we can’t—the models don’t do a perfect job, so people tried to evaluate what is the possible range of scenarios. What they did was took a single model, originally, and a single CO2 scenario up to doubled carbon dioxide and then had people all over the world run various scenarios. They ran 3,000 different runs, and in each one, they assigned slightly different values to the assignable parameters in the model. Unfortunately, not everything in the model is subject to equations derived from physics. They have to make the best estimate of a whole bunch of things.

They did something like 3,000 runs, and what they found is that none of ‘em gave less than one degree, and 15 percent of them gave more than five degrees so that the uncertainty is highly asymmetrical. The chances—according to the models, anyway—is that the warming will be bigger than three degrees is more than it’ll be less than three degrees.

Okay. Now, it’s becoming clear that CO2 is gonna produce more destructive storms. It’s eating away at our arctic ice, and one of the very important things is that the prediction is that there’ll be less food—less grain production for the major grains that are grown on the planet. Even though CO2 is a plant nutrient and you would think that as you raise CO2 in the air, plants would grow faster, it turns out that doubled CO2 in field experiments only increases it about something like 12 percent.

But there are two other things that are gonna happen. All grains are grown beyond their thermal optimum. In other words, we get more yield if it were a few degrees cooler, and the evidence is that for every degree Centigrade you warm the atmosphere, you lose 10 percent of grain production, and so if we had a three-degree increase, that would be a 30 percent decrease, 12 percent would be compensated by CO2.

Then there’s one more thing that’s more difficult to evaluate quantitatively, and that is all agriculturalists seem to agree that the warmer the planet, the more that pests are gonna—the greater the share of the crops that will be eaten by pests rather than by us. This is a tricky one because we’re headed for nine billion people, so we’re gonna have 25 percent increase in population, and if we were to get 20, 25 percent decrease in grain yield, this would mean we’d fall short by almost 70 percent or so.

People say to grow—to create a grain strain that will tolerate higher temperatures is gonna be very difficult, and so that’s not something that can be done quickly, if at all. Oops.

Now, ideally, what’s gonna happen—and it certainly will happen. The big question is how long will it take—is that we will get our energy from the sun and from wind and from nuclear fission and from biomass and from tides and many other things, but in order to stop the CO2 from rising, we have to reduce CO2 emissions by—to less than 10 percent what we’re producing now.

The only reason CO2—we’re lucky that about a quarter of the CO2 we produce is going into the ocean, and that would be the ultimate sink for CO2. Eventually, on a hundred-year timescale, take up most of the CO2 we produce, but it’s gonna take a very long time.

Let’s call this Utopia, so the big question is how long will it take to reach Utopia? That’s the time when we’re emitting less than 10 percent of the CO2 we now emit. You can make your own guess. I would guess that even 50 years is—it’s not gonna be possible even on that timescale. It’s gonna take longer. This has been made worse by the fact that fossil fuels are—there’s a glut of fossil fuel right now.

The Canadian tar sands, the natural gas that’s coming from shales, the petroleum that’s coming from North Dakota, FRACing, and—well, right now, I think—I called up a friend of mine and said, “Can you tell me how much of our energy we get from fossil fuel?” He didn’t have that number right away, but he did a little bit of looking around, and he concluded that it’s 84 percent. We’ve been using, for years, a number of 85 percent so that we’re not—we haven’t even started to ramp down the percentage.

But one startling fact is that in 1990, we were releasing about 20 billion tons of CO2 a year. Last year, we released about 32, so despite Kyoto, which was supposed to start the reduction of CO2 because of China and India industrializing, the use of fossil fuels has gone up and the percentage of our energy we get from that has stayed about the same.

We’re in for a long time that we’re dependent on fossil fuels. We have to have energy. You can’t cut down the energy. Well, we could conserve, and hopefully we will, but that’s not gonna solve the problem. It could be maybe 20 percent gain, something like that, but we’ve gotta go much further than that.

I would say that during this interim period of 50 or so years, when we’re getting major part of our energy from fossil fuels, and the CO2 content of the atmosphere is continuing to rise, we have—are gonna have really three options.

One is to do nothing and just cope with the consequences. I think that would be awful because most all scenarios suggest that it’s gonna lead to big trouble. Another one is to recapture CO2 from the atmosphere and bury it. We could do this during the transition period, or if, at the end of the transition period CO2 was unreasonably high, we could use it to pull CO2 back down. This is the only way to pull it back down. Otherwise, you have to wait for the ocean to do it, and that’ll take hundreds of years. The other option is gonna be increasing the reflectivity. Let me talk about each of those.

Klaus Lackner at Columbia has been working for 13 years to figure out how to pull CO2 back out of the air. A few years ago, he created this sketch—I should say when he first did it—oh, let me explain a bit. Up here, these are like mattresses this thick, and you can see how high they are by the height of the human figures—and they’re filled with a very special fiber—plastic fiber that Klaus and Ellen Wright, his associate, ran onto. It’s a commercial plastic used for water purification.

It has this amazing capability of trading CO2 for water. Put in dry air—and so when Klaus was thinking about this, he said this diagram probably ought to look like this ‘cause you would do this in dry lands rather than in New York. Anyway, this one is easier to look at.

[Interviewee:] [laughter].

[Wally Broecker:] This makes me feel at home.

[Interviewee:] [laughter].

[Wally Broecker:] This is kinda—whoops. This one is—I’m still have to get comfortable in the desert. The wind would just blow through these so there’s no fans or anything necessary. He has, in this particular version, 30 of these mattresses filled with fibers. He leaves it out for a few hours, and they—he picks up an optimum amount of CO2. He then brings these things down one at a time and puts them in these chambers.

Then, in the air, the CO2 and the air kicks water off of the plastic, so you put it down here—you give it—you could soak it with water. You could put cool steam in, but give it a lot of water vapor availability or water availability, and it kicks the CO2 back off again. Then you put the mattress back up, load it with water, the water goes off in the air and the CO2 from the air goes onto the plastic.

Why little modules like this? This module would take up about a ton of CO2 a day. That’s what’s produced by average 20 automobiles, so if you were to do automobiles with these, it would—you’d have to have one for every 20 automobiles. There’s 70 million automobiles on the planet right now, so you’d need three and a half million of these. Whatever we’re gonna do is huge.

How would you ever make three and a half million of these? Well, we make, what, 15 million automobiles a year, so if we got into an emergency and really decided we had to do something to stop the rise of CO2, we could turn our attention to manufacturing these.

Klaus has the idea that they should—each unit, when disassembled, should fit in a standard container so you can make them all in a few places like Ford assembly lines, and you could then ship the containers to the place where they’d be deployed. They’d be deployed in wastelands where you wouldn’t have all kinds of lawsuits about how ugly they look or whatever, and some of these—most of these places, the people would probably be delighted to have some employment, so his idea would be to put them in remote parts of our planet, and there are plenty of dry lands where this could be done.

He estimates that the cost of one of these would be about the cost of an automobile when mass produced. Certainly not the first one. The amount of material in it would be comparable to the amount of material in an automobile. Let’s see. There should be—oh.

If you were to—people reply to this by saying, “Well, why not just take CO2 out of the smokestacks and power plants where it’s 10 percent as opposed to 400 parts per million in the air?” Well, it turns out that while it’s more expensive to do this, it probably won’t be more than 30 to 50 percent more expensive than taking it out of stacks. Yeah?

[Interviewee:] What does he do with the CO2 that he collects?

[Wally Broecker:] Well, I was just getting to that. He has to—he would install these in dry lands under which there were suitable geologic strata to store the CO2. CO2 is now being stored in the standstone underneath the North Sea. It’s been going on for 18 years now with no problems, so yes, you have to have carbon capture and sequestration. You have to put it somewhere so it can’t get back into the air. That’s the second part of the problem. Klaus is working on this to prove that you can capture the CO2 and liquefy it because you’re gonna pump it down into the ground as liquid, supercritical CO2, to see if you can do that for a reasonable price.

He thinks he can do it for less than $100.00 a ton of CO2. That would—if you applied that to gasoline costs—would raise the price of gasoline about 90 cents a gallon. It’s not nothing, but it certainly—if we’re in an emergency, it’s affordable.

Okay. I just talked about automobiles, but obviously, you could do all the other sectors of—you could take out all the CO2 from home use, from power plants, using these devices. You would then need something like 15 million of them.

But when you think about it, everything we do every day involves putting CO2 in the air. You as an average American put something like 25 tons of CO2 in the air every year. The average person on the planet now is putting something like three or four tons—averaged over everybody—of CO2 in the air. This is not a minor problem. It is huge enterprise to undo what we’re doing.

Okay. I wanna talk about one other aspect to this and then I’ll let you ask questions. A man named Bediko, a Russian meteorologist, back in 1968 suggested that you could use CO2—I mean, SO2—could put it in the stratosphere and it would make little aerosols that would reflect away sunlight. Nothing more was said about that.

John Knuckles, who was, at one time, director of Livermore National Lab, but somewhat earlier than that—well, way back—he and I went to Wheaton College in Illinois and were good friends. Then we lost touch with each other in the ‘50s, and then he got in touch with me in 1983 or 4 and suggested I come to Livermore National Lab and spend a week doing interesting things with him, and so I—he was the architect—was the socker off of our H-bomb. He worked with Teller and made H-bombs. [laughter]. I said, “John, we’re not gonna work on H-bombs.”

[Interviewee:] [laughter].

[Wally Broecker:] I don’t know anything about ‘em. We have to do something useful.

[Interviewee:] [laughter].

[Wally Broecker:] We decided to look into the Bediko’s method. What would you have to do? Well, it turns out that the models would say that doubling CO2 is like the equivalent to turning up the strength of the sun by two percent. If you wanted to change the reflectivity of the earth, you’d have to reflect away two percent of the incoming sunlight.

Turns out that when you put SO2 in the stratosphere, it—within a timescale of weeks—gets converted to sulfuric acid aerosol, so it goes up at a gas and then it makes little liquid droplets that have a—I think a radius averaging three microns. I’ve got the diameter on there.

The optical properties of these little aerosols is that 80 percent of the light that hits them is forward scattered so it doesn’t do anything to cooling the earth, but 20 percent is back scattered, so this is what’s of interest. This would be back scattered into space.

In order to get this two-percent reduction equivalent in sunlight, you have to have huge amount of these aerosols. We did calculations of how much, and it turns out that we would have to put up three and a half times ten to the 13 grams per year. That’s huge, but volcano Pinatubo put just about that much all by itself, and that’s one reason we know a lot about this.

I was doing these calculations, and I wanted to know how much that would cost, so I called up Freeport Sulfur in Freeport—some sulfur company in Freeport, Louisiana, and they said it’s $225 a ton FOB. I don’t know. I think you gotta pay the transport. Anyway.

[Interviewee:] [laughter].

[Wally Broecker:] That—in 1982 or 3—for dollars was about eight billion dollars a year for the SO2. Then of course you have to get it up there, and Knuckles said, “Oh, we could use A-bombs” or something.

[Interviewee:] [laughter].

[Wally Broecker:] No, John, we don’t wanna get—this is all very bad in itself, and we don’t wanna make it any worse. I said we’ll fly 707s up there which were available at that time, so I called up Boeing and asked what the maximum amount of freight they’d ever carried on one of those, and they told me, and so I figured it out that if we had 707s flying around the clock up, dump, down, load, up, dump, down, load—say five hours or something to do a cycle—we’d need 700 of them running all the time.

[Interviewee:] Did you calculate the CO2 input from the 707s into the atmosphere? [laughter].

[Wally Broecker:] Well, we might have to put up more SO2.

[Interviewee:] [laughter].

[Wally Broecker:] But it’s—that would cost—again, in 19 early 80 dollars—something like ten billion, so maybe if we upgraded this and made it more reasonable, this would be 100 billion dollar solution.

Well, to solve the CO2 problem’s gonna cost trillions of dollars, so the unfortunate thing—I don’t think we should do this. I think this is bad, bad idea. One thing is that the distribution of SO2 is not gonna one for one cool the planet everywhere by three degrees. Some places will only be cooled by one. Other place will be cooled by five or something, and it’s gonna be patchy and it makes acid rain, it uses up ozone, but it’s gonna be tempting. Since money counts, all of you that are gonna be alive at that time—let’s say in 2045—you should worry about not doing this.

But as I said, we’re gonna have three choices. Either we’re gonna have to pull CO2 out of the atmosphere or out of power plants and bury it, or we’re gonna have to live with a much warmer earth, or we’re gonna have to do a bandaid which would mean we wouldn’t stop CO2 from rising, but we would compensate for it.

By the way, one other point is that you have to put these up every year because they gradually drift down from the stratosphere and make acid rain, of course, and the average residence time would be about a year to a year and a half, so you—again, we know that from Pinatubo. We would have to put it up again.

This has one advantage, which is often not—doesn’t often happen. Usually, when we interfere with nature, we’re stuck with it. This, you could say, don’t like it, you just stop, and of course, you have an accomplish—you’ve cooled it off for a couple years. But if you don’t like it, you let all the aerosols come down, and you’re back to where you were before.

Okay. We wrote a paper, and I showed you the title of that paper. We sent it—we diddle doddled with it, and we didn’t know whether it should get published or not. We sent it around to various people who—important people. Frank Press was Carter’s science advisor, and then he became president of the National Academy of Science. You can read this. You can see he didn’t like the idea. He said, “This is something we don’t wanna get into.” We were gonna have a meeting about this.

We got other letters from three or four other prominent people, and they all—for one reason or another—said don’t publish it, so we didn’t. It was never published. But my first wife, Grace, was in a dentist’s office, and she picked up and [inaudible] some garden magazine and hit on this. I had obviously wanted to talk to a Daily Telegraph newspaper in UK about this, and here he says, “Broker 700 jumbo jets running around the clock—“

[Interviewee:] [laughter].

[Wally Broecker:] “- could counter the warming produced by doubled CO2.” Then it gives some of the negative things, so this is the publication of our paper.

[Interviewee:] [laughter].

[Wally Broecker:] Okay. The bright side of—

[Interviewee:] [laughter].

[Wally Broecker:] - putting SO2 in the stratosphere and making little sulfuric acid aerosols is you get beautiful sunsets. This was after Pinatubo eruption in 1991, and this was after Mexican volcano El Chichon—I think it was Mexico—in 1984. This was in the Philippines. This one put up the full 32 million tons, but I think we can do without beautiful sunsets. [laughter]. That’s a big price to pay.

I’m gonna stop now, and I’m gonna open it up for questions. There probably a lot. Let me just summarize. Fossil fuels are plentiful, they’re cheap, they’re boxing alternative energy out of the market. CO2 is going up half again as fast in 2012 as it did in 1990, and there’s no indication that the amount that we put in is gonna be less in 2013, ’14, ’15 than it is now because these countries are still developing. Others may join them. If anything, the production of CO2 is gonna get bigger rather than smaller.

That being the case, we have to—and that we’re gonna be stuck with fossil fuels. We have to have energy to run the world, and we’re gonna be stuck with fossil fuels for at least 50 years. During that time, CO2’s gonna keep going up. The consequences are gonna get ever more severe, and so we’re gonna have to decide which of the three paths we follow, and we won’t make a conscious decision. We’ll be—if we make a decision, we should make a decision to find out how much it really costs to do this.

I didn’t mention that Lackner has never been able to get the money from anybody—from oil companies, from venture capitalists, from governments—to build a prototype. He thinks to build one of these units, automated, would cost something—the development costs might be 50 million dollars.

I mentioned at the beginning that we had this meeting Saturday, February 2nd. Attending were 21 of the best-known people associated with the CO2 problem, both science and policy, here at ASU, and a subgroup of five or six of us that were involved in that have written a letter that’s gonna be submitted to science. Larry Krause finished the letter today, and it’ll probably go out to all of the participants with a request that they sign it. It’ll be interesting to see how many will.

Jim Hanson, who many of you know of, was at the meeting. He has quite a different way of doing this. He thinks that by protesting loudly, you can stop things like the Keystone Pipeline development of coal. My attitude is that the amount of money that’s bound up in coal and Canadian Tar Sands is so big that they’ll just bulldoze over anybody that tries to get in the way. Big money talks.

Rather than trying to eliminate sources of fossil fuel, what we have to be prepared to do is take it back out of the air, and that will require a fee on carbon. That’s something that Hanson would agree to, although he would vote to give that money back to the public, but—raise the price of fossil fuels, but then give the extra money that was reaped in that way back to the public. I would say price on carbon better spent would go toward retrieving it from the atmosphere.

I’m 81. I ain’t gonna see much more of this, but you all will, and I’d give my eye teeth to be one of you, because it’s gonna be fascinating how this all plays out. I don’t think it’s gonna go away. It’s gonna become a bigger and bigger and bigger issue, and you’re gonna have to start—I hope—paying to do something about it. Thanks again.

[Female Voice:] This presentation is brought to you by Arizona State University’s Global Institute of Sustainability for educational and non-commercial use only.

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