"Geoengineering and Terraforming: the manipulation of climate on Earth and other planets” - An Interview with Warren Wiscombe of NASA- Goddard Space Flight Center
En-Ya Zhang (MSS Intern, Terra Linda High School)
Warren Wiscombe worked at the NASA- Goddard Space Flight Center for thirty years, researching the interaction between the sun, clouds, and aerosols. He received a B.S. in Physics at the Massachusetts Institute of Technology (M.I.T.) and a Ph.D. in Applied Maths from the California Institute of Technology (CalTech). This event, "Geoengineering and Terraforming: the manipulation of climate on Earth and other planets", took place on January 29, 2020, in Room 207, at Terra Linda High School. ( 320 Nova Albion Way)
1. Were you always interested in geoengineering and terraforming? Or were they topics that piqued your interest later on in life?
I started in climate in 1970. For the first 10 years, we never discussed geoengineering because climate science was primitive and we were still hashing out the basics. However, in the early 1980's, the work on Nuclear Winter (the famous TTAPS paper) caught everyone's attention, and that was a form of unintentional geoengineering. It started us down the road of thinking about how humans could put aerosol in the stratosphere and alter the climate, even though the word geoengineering was not even defined yet.
The asteroid impact work of Alvarez et al. piggybacked on the Nuclear Winter work and even used the same models. That work also caught the attention of all climate scientists at the time.
In spite of the attempt to rewrite history by young climate scientists, we were far from sure about global warming until the end of the 1980's. Hansen was privately criticized by 90% of my colleagues for testifying to Congress in 1989 that "global warming is here", and in fact he was wrong in ascribing the US drought at that time to global warming. So the climate field was obviously not rushing to counteract something they weren't sure was even real.
It was only as the 1990's wore on, and global temperatures contined their climb, that the idea of geoengineering gained any traction at all. Toward the end of the 90's, Ken Caldeira raised the profile of ocean acidification, a consequence of CO2 rise that could not be counteracted except by removing CO2 from the atmosphere, which more or less began the CCS branch of geoengineering.
Even in the 2000-2010 period, there was a lot of internal conflict within the field about geoengineering. I was an early advocate, and as Chief Scientist of a DOE climate program, I strongly urged DOE to start a geoengineering research program, but they were afraid of it and rebuffed my idea. Paul Crutzen, then Phil Rasch and other early adopter, gave more credibility and respectability to geoengineering, but it was still an uphill battle against geoengineering deniers like Alan Robock, who staked out the moral high ground and claimed it was immoral to do geoengineering because there would be winners and losers and the losers would have no voice.
As to terraforming, it was a fringe subject until recently -- not disrespected, but hardly anyone in planetary science worked on it. I followed the subject, but never worked on it. Chris McKay of NASA Ames was its biggest student and spokesman on the research side. Nobody would support implementation, because NASA had a "Planetary Protection Officer" whose sole job was to prevent any meddling with other planets. NASA requires all spacecraft to be perfectly sterile, etc. I have always supported terraforming because I strongly believe, based on my study of habitability, that we are likely the only intelligent species with technology for space travel in the entire galaxy. Our species will die out if we remain on Earth -- that is 100% certain. So our only shot at longevity is to go to other planets. But our study of 1000s of exoplanets has revealed that few if any are suitable for human life. So those exoplanets will need to be terraformed. We need to start figuring out how to do that. K.S. Robinson gave us some hints in his books Red Mars, Green Mars, but there is a lot more research to do. Perhaps, for example, we need to prepare planets by sending appropriate bacteria 1000 years before we send humans.
2. Geoengineering is a rather controversial topic. Do you think that the outcome of the process would be worth the consequences?
I think humans have been doing geoengineering for 10,000 years or more, certainly since the start of agriculture, and even before that with widespread burning of forests and grasslands. So to me the only question is, do you geoengineer purposely, or inadvertently? I pick purposely. Also, geoengineering is training wheels for terraforming, which I also favor. Hard as it seems right now, geoengineering the Earth is a lot easier than terraforming other planets, and it is time for us to get started on that steep learning curve.
I don't buy the moral arguments against geoengineering. Survival of humanity and civilization trumps fear of unintended consequences.
3. What kinds of geoengineering projects do you do at the NASA-Goddard Space Flight Center?
Goddard didn't do any work on geoengineering when I was there. They were afraid of the topic. Scientists as a group are actually quite timid. Science managers are even more timid. There is very little real risk-taking, and risk-takers are often harshly criticized. I don't think the public quite realizes how conservative science is.
4. Do you think that terraforming Mars would be a possibility in the near future? Why or why not?
Not in the near future. We don't even have an algorithm for doing it, a checklist if you will. My own concern is that you don't just plop down humans on Mars and expect things to work out. You have to prepare the soil and the atmosphere first. If you study soil on Earth, you realize that it doesn't exist on Mars, because "soil" is full of microbes that make plants possible. Mars has no such microbes. If we are going to grow stuff on Mars, we need a better atmosphere and we need soil that works (the guy in The Martian grew potatoes using human poop, but they never mentioned whether other necessities, like nitrogen-fixing bacteria, would also be needed). As to the atmosphere, you need a thicker atmosphere with more CO2, and you need some O2 to form an ozone layer to protect plants from UV radiation. You need to move the plentiful water from under the surface into the atmosphere, where some of it will dissociate into H2 and O2.
Edgar Rice Burroughs described some of this in his Princess of Mars series of books in the 1800s. The Martians were making their own atmosphere.
5. What do you think is the most effective form of geoengineering? Why does is have a more positive impact that others?
The Royal Society report on geoengineering (I showed the cover in my talk) has a scatterplot of the various geoengineering methods with affordability on one axis and effectiveness on the other. Stratospheric aerosols wins hands down -- it is the cheapest and most effective. Reforestation comes in 2nd -- just as affordable as aerosol, but not as effective (although it does draw CO2 out of the air, which aerosol does not, so actually I think it is a better all-around solution). A 2019 paper estimated what level of reforestation would be required to draw down the CO2 over the next 50 years or so, and it was quite reasonable in terms of area required, and cost. It was in all the news. If you need to find it, let me know and I'll locate it.
Carbon Capture and Storage (CCS), of which reforestation is an example, lags way behind aerosol as a geoengineering technology. There are some great ideas, but they have never been proven at any kind of reasonable scale. I like the idea of injecting CO2 into rocks under the ocean (the video I showed) but it remains just an idea. Years of work are needed to even do a demonstration at scale, much less begin to actually reduce CO2 in the air.
CCS is a better technique because it gets at the heart of the problem -- too much CO2 in the air -- and it deals with ocean acidification, which aerosol (or Solar Radiation Management) does not. However, if we are to do anything in the next 30 yr, SRM is the only technology available.
6. What do you think is the most interesting component of terraforming?
How do we seed an exoplanet with microbes, and can the process be radically accelerated so that it succeeds in a timeframe relevant to humanity (like 1000 years as opposed to a million years)?
7. What do you think is the most difficult part of terraforming?
Preparing the atmosphere for human occupation. We have some ideas, but study of the evolution of Earth's atmosphere has shown how hard it is to accomplish much on time scales below a million yr. It took over a billion yr to bring the O2 up to modern levels, starting 2.4 billion yr ago, for example. CO2 is also complex, since on Earth it participates in a complex carbon cycle involving rain, plankton, plate tectonics, burial of carbonate sediments at sea, plus volcanoes, all of which serve to regulate CO2 -- one or more of these factors are likely to be absent on any given exoplanet.
En-Ya Zhang (MSS Intern, Terra Linda High School)
Warren Wiscombe worked at the NASA- Goddard Space Flight Center for thirty years, researching the interaction between the sun, clouds, and aerosols. He received a B.S. in Physics at the Massachusetts Institute of Technology (M.I.T.) and a Ph.D. in Applied Maths from the California Institute of Technology (CalTech). This event, "Geoengineering and Terraforming: the manipulation of climate on Earth and other planets", took place on January 29, 2020, in Room 207, at Terra Linda High School. ( 320 Nova Albion Way)
1. Were you always interested in geoengineering and terraforming? Or were they topics that piqued your interest later on in life?
I started in climate in 1970. For the first 10 years, we never discussed geoengineering because climate science was primitive and we were still hashing out the basics. However, in the early 1980's, the work on Nuclear Winter (the famous TTAPS paper) caught everyone's attention, and that was a form of unintentional geoengineering. It started us down the road of thinking about how humans could put aerosol in the stratosphere and alter the climate, even though the word geoengineering was not even defined yet.
The asteroid impact work of Alvarez et al. piggybacked on the Nuclear Winter work and even used the same models. That work also caught the attention of all climate scientists at the time.
In spite of the attempt to rewrite history by young climate scientists, we were far from sure about global warming until the end of the 1980's. Hansen was privately criticized by 90% of my colleagues for testifying to Congress in 1989 that "global warming is here", and in fact he was wrong in ascribing the US drought at that time to global warming. So the climate field was obviously not rushing to counteract something they weren't sure was even real.
It was only as the 1990's wore on, and global temperatures contined their climb, that the idea of geoengineering gained any traction at all. Toward the end of the 90's, Ken Caldeira raised the profile of ocean acidification, a consequence of CO2 rise that could not be counteracted except by removing CO2 from the atmosphere, which more or less began the CCS branch of geoengineering.
Even in the 2000-2010 period, there was a lot of internal conflict within the field about geoengineering. I was an early advocate, and as Chief Scientist of a DOE climate program, I strongly urged DOE to start a geoengineering research program, but they were afraid of it and rebuffed my idea. Paul Crutzen, then Phil Rasch and other early adopter, gave more credibility and respectability to geoengineering, but it was still an uphill battle against geoengineering deniers like Alan Robock, who staked out the moral high ground and claimed it was immoral to do geoengineering because there would be winners and losers and the losers would have no voice.
As to terraforming, it was a fringe subject until recently -- not disrespected, but hardly anyone in planetary science worked on it. I followed the subject, but never worked on it. Chris McKay of NASA Ames was its biggest student and spokesman on the research side. Nobody would support implementation, because NASA had a "Planetary Protection Officer" whose sole job was to prevent any meddling with other planets. NASA requires all spacecraft to be perfectly sterile, etc. I have always supported terraforming because I strongly believe, based on my study of habitability, that we are likely the only intelligent species with technology for space travel in the entire galaxy. Our species will die out if we remain on Earth -- that is 100% certain. So our only shot at longevity is to go to other planets. But our study of 1000s of exoplanets has revealed that few if any are suitable for human life. So those exoplanets will need to be terraformed. We need to start figuring out how to do that. K.S. Robinson gave us some hints in his books Red Mars, Green Mars, but there is a lot more research to do. Perhaps, for example, we need to prepare planets by sending appropriate bacteria 1000 years before we send humans.
2. Geoengineering is a rather controversial topic. Do you think that the outcome of the process would be worth the consequences?
I think humans have been doing geoengineering for 10,000 years or more, certainly since the start of agriculture, and even before that with widespread burning of forests and grasslands. So to me the only question is, do you geoengineer purposely, or inadvertently? I pick purposely. Also, geoengineering is training wheels for terraforming, which I also favor. Hard as it seems right now, geoengineering the Earth is a lot easier than terraforming other planets, and it is time for us to get started on that steep learning curve.
I don't buy the moral arguments against geoengineering. Survival of humanity and civilization trumps fear of unintended consequences.
3. What kinds of geoengineering projects do you do at the NASA-Goddard Space Flight Center?
Goddard didn't do any work on geoengineering when I was there. They were afraid of the topic. Scientists as a group are actually quite timid. Science managers are even more timid. There is very little real risk-taking, and risk-takers are often harshly criticized. I don't think the public quite realizes how conservative science is.
4. Do you think that terraforming Mars would be a possibility in the near future? Why or why not?
Not in the near future. We don't even have an algorithm for doing it, a checklist if you will. My own concern is that you don't just plop down humans on Mars and expect things to work out. You have to prepare the soil and the atmosphere first. If you study soil on Earth, you realize that it doesn't exist on Mars, because "soil" is full of microbes that make plants possible. Mars has no such microbes. If we are going to grow stuff on Mars, we need a better atmosphere and we need soil that works (the guy in The Martian grew potatoes using human poop, but they never mentioned whether other necessities, like nitrogen-fixing bacteria, would also be needed). As to the atmosphere, you need a thicker atmosphere with more CO2, and you need some O2 to form an ozone layer to protect plants from UV radiation. You need to move the plentiful water from under the surface into the atmosphere, where some of it will dissociate into H2 and O2.
Edgar Rice Burroughs described some of this in his Princess of Mars series of books in the 1800s. The Martians were making their own atmosphere.
5. What do you think is the most effective form of geoengineering? Why does is have a more positive impact that others?
The Royal Society report on geoengineering (I showed the cover in my talk) has a scatterplot of the various geoengineering methods with affordability on one axis and effectiveness on the other. Stratospheric aerosols wins hands down -- it is the cheapest and most effective. Reforestation comes in 2nd -- just as affordable as aerosol, but not as effective (although it does draw CO2 out of the air, which aerosol does not, so actually I think it is a better all-around solution). A 2019 paper estimated what level of reforestation would be required to draw down the CO2 over the next 50 years or so, and it was quite reasonable in terms of area required, and cost. It was in all the news. If you need to find it, let me know and I'll locate it.
Carbon Capture and Storage (CCS), of which reforestation is an example, lags way behind aerosol as a geoengineering technology. There are some great ideas, but they have never been proven at any kind of reasonable scale. I like the idea of injecting CO2 into rocks under the ocean (the video I showed) but it remains just an idea. Years of work are needed to even do a demonstration at scale, much less begin to actually reduce CO2 in the air.
CCS is a better technique because it gets at the heart of the problem -- too much CO2 in the air -- and it deals with ocean acidification, which aerosol (or Solar Radiation Management) does not. However, if we are to do anything in the next 30 yr, SRM is the only technology available.
6. What do you think is the most interesting component of terraforming?
How do we seed an exoplanet with microbes, and can the process be radically accelerated so that it succeeds in a timeframe relevant to humanity (like 1000 years as opposed to a million years)?
7. What do you think is the most difficult part of terraforming?
Preparing the atmosphere for human occupation. We have some ideas, but study of the evolution of Earth's atmosphere has shown how hard it is to accomplish much on time scales below a million yr. It took over a billion yr to bring the O2 up to modern levels, starting 2.4 billion yr ago, for example. CO2 is also complex, since on Earth it participates in a complex carbon cycle involving rain, plankton, plate tectonics, burial of carbonate sediments at sea, plus volcanoes, all of which serve to regulate CO2 -- one or more of these factors are likely to be absent on any given exoplanet.
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