Asking the hard questions about climate change: Q&A with climate and geoengineering expert

Dec 18, 2012

David Keith is Gordon McKay Professor of Applied Physics at Harvard's School of Engineering and Applied Sciences, and Professor of Public Policy at Harvard Kennedy School. The award-winning scientist, who was named one of TIME magazine's Heroes of the Environment in 2009, has worked near the interface of climate science, energy technology, and public policy for twenty years. He divides his time between Boston and Calgary, where he serves as president of Carbon Engineering—a start-up company developing industrial-scale technologies for capture of CO2 from ambient air. Here, Keith answers questions about his research and ideas for reducing climate change using innovative and sometimes controversial methods.

Q. TED describes you as a "wildly original thinker [who] challenges us to look at climate solutions that may seem daring, sometimes even shocking." What are some of your favorite, daring ideas to reduce climate change?

My favorite idea is pedestrian: put a price on to discourage use of the atmosphere as a free waste dump. This idea is at once commonplace and radical. A price on emissions such as a tax is admission that government does not know exactly which methods will prove most effective in reducing emissions, so the best way to make progress is to build the cost of emissions into prices across the economy and let firms and individuals figure it out in a distributed way. Most carbon-related policy to date has focused on promoting particular technologies such as solar on . While some of this has been useful, the net effect has been to spend very large amounts of money (the world now spends more than $200 billion per year on ) on things that are relatively cost-ineffective as measured by their short-term ability to restrain emissions.

Q. You gave a talk at Harvard recently titled "The Risks and Efficacy of Solar Engineering." Solar engineering involves injecting a substance into the upper atmosphere that will reflect some sunlight back into space in order to cool the earth. What are the main benefits of this method and do the benefits outweigh the risks?

The benefit is that solar geoengineering may enable us to reduce the risk of climate change from emissions that have already occurred. While we will ultimately have to cut emissions to nearly zero to stabilize the climate, "ultimately" is a long way off, and near-term emissions reductions do very little to reduce near-term climate risks such as temperature extremes that may cause crop losses whose impacts will fall on the most vulnerable populations over the next half century. Solar geoengineering offers the prospect of materially reducing climate risk for current generations and of slowing large-scale climatic change such as the loss of Arctic Sea ice. While it sounds hyperbolic and promotional, there is literally no other method we know to achieve this.

The enormous power of solar geoengineering— the leverage that enables small low-cost inputs to create profound climate changes— presents novel and serious risks. The greatest challenges are not technical but rather the development of effective governance. Solar geoengineering cannot be localized, so implementations by one country will affect others in ways that could— in the worst-case— be profoundly damaging. We require governance systems that can manage near-term research in a way that balances the benefits of knowledge against risks, and manages decisions about deployment in a way that is able to achieve some measure of democratic legitimacy in a multipolar world.

Q. How can you be confident that working on solar geoengineering will not reduce popular and political will for reducing greenhouse gas emissions?

I can't be. On the contrary, I think there is a real prospect that if solar geoengineering is found to be effective it will reduce political will to cut emissions compared to what it would be otherwise. Current political will to cut emissions is low so that may not make things materially worse. If one is optimistic, one might hope that the injection of this new technology into climate policy will energize the topic, breaking the static trench warfare that now characterizes much of the debate about climate and perhaps producing a better outcome. But, that is a wish, not a prediction.

Q. Why have humans failed so spectacularly to curb greenhouse gas emissions so far – and is there is a no-turning-back deadline regarding global warming?

I don't know. One answer may lie in the fact that language of environmental advocacy has become increasingly technocratic. Calls for action often stress quantitative measures and self-interest. We are urged to protect the natural environments because of the "ecosystem services" they yield. These arguments have merit, but I suspect they obscure much of what actually drives people's choices. If we are protecting a rain forest because it stores carbon or yields wonder drugs, then we should be happy to cut down the forest if some carbon storage machine or molecular biotech lab can better provide these services. The utilitarian benefits of the natural world are real, but for me they are a grossly insufficient measure of its value. While I may be an extreme, I think I am not alone, and I suspect that a more directly value-driven conversation about climate might be more effective than the current debate.

Our climate choices would be easy if we really were facing an imminent existential threat. A true emergency justifies extreme measures, a narrow focus on a single problem and suspension of democratic due process. Imagine how the world might collaborate if we discovered a massive asteroid inbound for a 2050 impact. But, this is not what we face. Claims that threatens a similarly sharp catastrophe are a rhetorical device to avoid an honest debate about the trade-offs at the heart of climate policy and about the values that drive our choices.

Q. Outside the office, you are an avid hiker and have adventured through the Canadian wilderness, the high Arctic, and the Himalayas. Have these experiences shaped your approach to your work on the environment and climate?

I have been unusually lucky in getting a chance to experience big wilderness, to go on multi-week expeditionary trips away from other people in places like the Canadian high Arctic. This is certainly related to my work on exploring non-utilitarian justifications for action, though I don't think much about work when I am outside.

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Claudius
2.4 / 5 (14) Dec 18, 2012
What are some of your favorite, daring ideas to reduce climate change?


Keep on doing nothing. It's been working wonderfully well for the past 16 years.
VendicarD
3.5 / 5 (11) Dec 18, 2012
Yes. Global temperatures have only risen 0.1'C over that periodm ocean level rise is accelerating, and the Arctic ice cap is now nearly ice free in summer.
Claudius
2.7 / 5 (12) Dec 18, 2012
https://en.wikipe...A%29.png

This graph shows a steady increase in sea level since 1870. Long before anthropogenic CO2 levels could have possibly played a role.

https://en.wikipe...evel.png

This graph covering about 18,000 years shows that sea levels had an accelerating increase until modern (the last 8000 years) times, at which the rate of increase decreased significantly.

The question isn't whether climate is changing, it is what degree of influence humans have had. These changes have been happening for a very long time and pre-date human civilization. It is ridiculous to point to these changes and conclude that humans are having a significant effect. Non sequitur.

Howhot
3.4 / 5 (10) Dec 18, 2012
The question isn't whether climate is changing, it is what degree of influence humans have had.

You know, if the recent global heat gains where a long time effect then geological records would have shown that. They don't! Historic records only show extreme temperatures in the past 160 years or so. Its such a sharp change that it's like a railroad spike at the end of the a graph. Nothing has ever happened as fast in all of global history! It happens to correspond with growing human population and creation of excessive atmospheric CO2 production. (ie AGW).

So it is with some urgency, that we need to remove the root causes of AGW, namely burning carbon based fossil fuels. We need to shift immediately to green renewable energy supplies for everything! Solar, Wind, Wave ... are 3 easily tapped energy sources. It's Non sequitur!

Its stupid. really stupid to let man made CO2 pollution bake everyone into a heat wasted oblivion.
gregor1
1.7 / 5 (11) Dec 19, 2012
Not true Hottie. In the Younger Dryas temperatures rose 10 degrees celsius in a decade.
http://www.ncdc.n...ta4.html
The earth has been going through warming periods at roughly 1,000 year intervals since the Minoan warm period, which was followed by the Roman and Medieval warm period. The Mann Hockey stick has long been discredited and there are numerous studies that show the modern warming as nothing unique. Here's Greenland
http://wattsupwit...0-years/
gregor1
1.8 / 5 (10) Dec 19, 2012
And for those who like graphs go here

"The evidence shows repeatedly that global warming is not unprecedented and according to Ruddiman (2001) as well as Singer & Avery (2006), global warming is a regular cyclic phenomenon on planet Earth. In fact, the normal global mean temperature for planet earth given the Phanerozoic history, is actually 19.5 degrees Celcius; a full three degrees higher than the present mean."
http://climate.ge...011.net/
runrig
4.3 / 5 (6) Dec 20, 2012
And for those who like graphs go here

"The evidence shows repeatedly that global warming is not unprecedented and according to Ruddiman (2001) as well as Singer & Avery (2006), global warming is a regular cyclic phenomenon on planet Earth. In fact, the normal global mean temperature for planet earth given the Phanerozoic history, is actually 19.5 degrees Celcius; a full three degrees higher than the present mean."
http://climate.ge...011.net/


Ever heard of "Milankovitch cycles" ... you know ( don't you surely? ) that the Earth has eccentricities in its orbit. And low and behold, would you believe it ... that affects the planets heat budget, especially in the NH where there is most land. This over millennia leads to ice build-up, with feed-backs that reinforce the cycle. Please try and grasp this as the primary cause of warm/cold periods.
gregor1
1.4 / 5 (7) Dec 20, 2012

"Historic records only show extreme temperatures in the past 160 years or so. Its such a sharp change that it's like a railroad spike at the end of the a graph. Nothing has ever happened as fast in all of global history! "

runrig I was replying to the above from How hot. I'm well aware of these cycles
VendicarD
4 / 5 (8) Dec 20, 2012
GregorTard can't even get the sign of the temperature change right.

The Younger Dryas - you ass - was an abrupt cooling that occurred as the earth's climate was exiting the last ice age.

"Not true Hottie. In the Younger Dryas temperatures rose 10 degrees celsius in a decade." - gregorTard

GregorTard's own reference doesn't even agree with him...

"Earth's climate began to shift from a cold glacial world to a warmer interglacial state. Partway through this transition, temperatures in the Northern Hemisphere suddenly returned to near-glacial conditions (Figure 6). This near-glacial period is called the Younger Dryas,"

gregorTard quotes without reading, comments without understanding, and gets the sign of the change wrong.

The abrupt change has been linked to changes in ocean circulation cause by a rapid influx of cold water which was dumped into the ocean as a massive glacial dam broke.

Poor gregorTard. He just can't seem to grasp science.
VendicarD
4 / 5 (8) Dec 21, 2012
If you like 50 year old graphs, yes.

"And for those who like graphs go here" - GregorTard

Now what are the qualifications of GregorTard's source this time.

"I graduated from the University of Melbourne on ISO:1996-March-16 and have a Bachelor of Science degree"

"In the decade spanning 1996-2005, I've worked in the petroleum industry"

In other words the Blog referred to by GregorTard is written by a non-scientist with a BSC in geology (nothing), who worked for a short time in the oil industry.

Bahahahahahaha.........

Idiot.
VendicarD
4 / 5 (8) Dec 21, 2012
And yet you have just demonstarated that you are not aware of them at all.

"I'm well aware of these cycles" - GregorTard

Educate yourself.. Moron...

Here is a real scientist to help you.

http://vimeo.com/55930802

http://vimeo.com/55930801
gregor1
1 / 5 (4) Dec 21, 2012
I was referring to the warming at the end of the
younger Dryas (After the initial masive cooling) in response to Howie's false assertion that the Earth had never warmed this fast.
http://wattsupwit...used-it/
Howhot
not rated yet Dec 26, 2012
Greogr, your numbers are just flat lies. (They mislead you, and you know with absolute conviction what you say is true, but the you data is wrong). Greg, you know the Watts-up site is stack of steamy poo when it comes to facts. Every item on Watts-up is suspect. So while I appreciate your efforts to find counter arguments to my debate points, I wish you would try to find some neutral sources.

Look, here is the debate point; "How can global temperatures rise as fast as they have without global civilization as the cause"? Gregor, you have satellites, ocean instruments, etc, and scientific expeditions measuring historical weather and climate over vast areas. Greg dude, the evidence of global warming is in your face, and you want to deny it?

Howhot
not rated yet Dec 26, 2012
Gregor, Directly to your point, the "younger Dryas" only really effected the norther hemisphere (it was a glacial cooling period). Nothing to do with present-day AGW (industrial/population based) global temperature increase that is increasing at a rate that will result in a global extinction. What is frightening my friend, Gregor is that global temperatures trends are on a rapid pace towards extinction with one cause, burning fossil fuels.

Once you realize that you can help man-kind by buying a Prius, or doing solar, or choosing organic, or insulating your windows... etc that, as one soul individual you can make one small statement. Many small statements can effect industry, governments and the world.

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