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Does the Paris agreement open the door to geoengineering?

Dan Farber, professor of law | December 14, 2015

The Paris establishes an aspiration goal of holding climate change to 1.5°C, with a firmer goal of holding the global temperature decrease “well below” 2°C. As a practical matter, the 1.5°C goal almost certainly would require geoengineering, such as injecting aerosols into the stratosphere or solar mirrors.

Even getting well below 2°C is likely to require steps of that kind or a technological breakthrough for another kind of geoengineering, removing CO2 from the atmosphere. None of this has to happen soon, but sometime between now and the end of the century, something along these lines would probably be required.

It’s always good to begin with the actual text of the agreement. Here’s the language of the agreement about the goal in Article 2(1)(a): “Holding the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 °C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change.”

Admittedly, this language is stated as an aim of the agreement rather than a mandate, but it’s worth thinking about what would be necessary to accomplish this aim. And it’s possible that it’s really just intended as symbolic, like the 1972 Clean Water Act’s long-forgotten goal of eliminating all water pollution by 1985.

Nevertheless, the Paris Agreement does place these temperature goals on the table, and we should give them careful consideration. I don’t quarrel with the idea that it would be desirable to attain these goals if we can. It is true that a number of scientists now think that the 1.5° target is needed to avoid the risk of dangerous climate change. So if there’s a realistic way to reach this target, or at least something under 2°, we should certainly give that serious consideration.

The question, however, is whether it is feasible to reach that goal through emission cuts. On that score, as Ann explained in an earlier post, there is considerable doubt. On an optimistic view, the goal is achievable — but only with immediate, rigorous emissions reductions combined with new technologies to remove CO2 from the atmosphere.

Ann Carlson points out that extraordinary efforts would be required for a country like the U.S., like increasing our current use of renewables thirtyfold. This is consistent with what I’ve read on the subject.

For instance, a recent summary of the literature concludes: IPCC results suggest that limiting temperature increase to 1.5°C by 2100 would require concentration of less than 430 ppm CO2-eq), an enormous challenge. . . . While the literature on the feasibility of reaching this target remains scarce, aggressive mitigation strategies would be fundamental, without any further delay. This entails not only swift global cooperation and exemplary institutional agreements but also massive investments in decarbonizing the global economy with zero net emissions before the end of the century as well as substantial and early negative emissions, particularly carbon dioxide removal strategies . . . . While some argue that a 1.5°C scenario is still feasible, others judge it as no longer within reach.

I would not bet the house, let alone the planet, on “swift global cooperation,” “exemplary institutional arrangements,” and “massive investments” happening quickly. This suggests that, much as we need to cut emissions, emissions are probably not going to get us to 1.5°.

Indeed, I have doubts about whether the political will exists to make the huge effort required even to achieve the 2° goal purely through emission cuts. Any realistic trajectory involves, at the least, new technologies to remove massive amounts of carbon from the atmosphere (which one scientist has called a “technological utopia”).  Short of enormous scientific breakthroughs one that front, solar radiation management to reduce the light reaching the surface seems necessary instead.

For these reasons, it appears to me, geoengineering begins to look necessary as a practical matter if we are going to hit such ambitious goals. Although it involves risks, the risks are less severe if we make a strong an effort as possible to cut emissions first, so that geoengineering doesn’t need to carry so much of the weight of emissions reductions.

I’m not particularly a fan of geoengineering, and I will be happy to be wrong about this. Maybe new energy technologies will be able to get us the kinds of cuts we need quickly and cheaply enough to attain the goals. Otherwise, though, if we are serious about those temperature targets, we may end up with little other choice than layering some geoengineering efforts on top of aggressive emission cuts.

Cross-posted from the environmental law and policy blog Legal Planet.

Comments to “Does the Paris agreement open the door to geoengineering?

  1. President Eisenhower’s 1961 Farewell Address included the following warning:

    “The prospect of domination of the nation’s scholars by Federal employment, project allocations, and the power of money is ever present – and is gravely to be regarded.”

    Global warming is one consequence of our failure to learn from his warning.

  2. It’s laughable that they are trying to “legalize” the covert geoengineering programs that are ALREADY in place worldwide. Please visit for evidence of this crime against humanity! The weather has been controlled for decades by use of toxic aerosols sprayed from planes, in conjunction with ionospheric heaters (HAARP).

  3. It takes an absolutely horrendous legal argument to make political science actually look like science in comparison, yet Dr. Dan Farber has accomplished this — again. I am assuming here Dr. Farber’s goal is to point out what may be the most dangerous weakness|omission in the climate accord, without providing any credible argument for what he claims is inevitable.

    What unearthly power forces him to keep secret his otherwise vehement opposition to this policy, which he suspects is awful? He is not a closeted environmentalist fooling the oil companies, so whom then? Shakespearean, Machiavellian, or Byzantine? You choose.

  4. Dan Farber again stretches credulity while supporting the profiteers. He quotes the goal of preventing climatic temperature increase to, in the headline, leaving the door open to geoengineering, and then proceeds to assume, in the body of the text, that his particular calorie counting darn near necessitates geoengineering.

    This is Chamber of Commerce-style editorializing typical of someone trying to buffalo his readers. Embarrassing, damaging salesmanship. Please stop publishing this “most favored” buffoonery. Ditto to the ocean “pasteur restoration ‘expert'” who is claiming credit for cyclic reversals in fishery populations, possibly aided by climate change (such as increases in freshwater melt) in the very short term.

    No, we don’t need to read your personal blog or the National Review to understand your miracle hair-growth formula. Farber et al get off the payroll.

  5. I certainly don’t see this as at all necessary. My modeling team, SWITCH and a number of other efforts all find that — with some sensible carbon-emissions pricing — the 2-degree max target could be met well before 2050 … more like 2030.

    lots of caveats, of course, but the high ambition coalition, if anything, is just that.


  6. I find Professor Farber’s proposal problematic on a number of levels. First, as many commentators have noted in recent years, general circulation models are not sufficiently granular to permit us to assess when we’ve reached critical climatic thresholds that might necessitate deployment of SRM approaches. And by the time we determined these, it would be too late. (See the recent work of Columbia professor Scott Barrett, for example, who used to be an effusive supporter of climate geoengineering.)

    Second, Professor Farber suggests that we could deploy SRM options only after we had done everything we can to mitigate. However, such a proposal is fraught with the threat of what we call a “moral hazard,” i.e. if you tell world leaders that we can unfurl a protective blanket over the Earth at some in the future, they likely will scale back their projections of what “can be done” in terms of mitigation, and the supple and non-binding nature of the commitments in the Paris Agreement could do nothing to prevent this.

    This could make very real the potential threats associated with SRM deployment, including shutting down the monsoons in South Asia, threatening forests in the Amazon, depletion of the ozone layer, and massive pulse of heat should be ever cease using said technologies.

    From where I sit, a far more sensible approach would be to: (a) Work to enhance mitigation through more funding of R&D on renewable energy and energy efficiency approaches, as well as research on carbon dioxide removal schemes, which pose far less dire transnational impacts; and (b) Focus on reducing short-lived, potent greenhouse forcers, e.g. black carbon, HFCs and ozone.

    As Durwood Zaelke recently concluded, “Cutting the short-lived climate pollutants can avoid 0.6C of warming by 2050 and 1.5C by 2100, compared to cutting carbon dioxide, which can avoid 0.1C by 2050 and 1.1C by 2100.”

  7. I find Professor Farber’s proposal highly problematic on a number of levels. First, as several commentators have recently noted, including Scott Barrett at Columbia, who was at one time a fulsome supporter of SRM geoengineering, it’s not practical to hold SRM in abeyance for the “right moment,” because we’re never likely to have sufficiently granular GCMs to assess said thresholds.

    Moreover, I think there’s a serious moral hazard issue posed by a proposal that says deploy SRM “after” we’ve mitigated as much as we can. If one signals to the world community that we’re poised to open the sulfur dioxide umbrella at some point, it’s likely that many States will scale back their mitigation commitments, and we’ll face some of the dire potential implications of deploying said technologies, including the termination effect, ozone depletion, and potential knock-off effects on net primary productivity. The Paris Agreement certainly would not preclude this scenario given its extremely supple commitments both in form and process.

    A far more sensible approach, from where I sit, is to focus on carbon dioxide removal research while: (a) Continuing to focus on reducing GHG emissions; and (b) Increase efforts to reduce highly potent, short-lived forcers, e.g. ozone, HFCs and black carbon.

    As Zaelke recently concluded, “Cutting the short-lived climate pollutants can avoid 0.6C of warming by 2050 and 1.5C by 2100, compared to cutting carbon dioxide, which can avoid 0.1C by 2050 and 1.1C by 2100.” The coda to Paris should not be capitulation to a dystopian future.

  8. Just how engineering the dimming of the sun which powers photosynthesis, the most potent part of CO2 ecology, will improve things is a dubious issue. The only way such solar dimming engineering can be presented is if one leaves photosynthesis out of the equations. That is an engineers prescription for chaos.

    On the other hand there are safe, simple, sustainable, immediately deployable, and best of all very inexpensive methods of enhancing photosynthesis on this blue planet. The new Paris Accord very specifically endorses, even demands, the enhancement of natural photosynthesis by restoring plant life in trees and in seas.

    My work, the largest trial of ocean pasture restoration covering nearly 50,000 sq. km in 2012 in the North Pacific, showed that the potency and immediacy of restoring nature simply works! While some say the proof is in the pudding I can do one better as from my restored ocean pasture the largest catch of salmon in Alaska history was produced. Where 50 million Pink Salmon were expected to be caught the following year in Alaska, that would be a fantastic catch, instead 226 million Pink salmon were caught.

    Today scores of millions of meals of that healthy salmon are being served to needy American kids in the USDA food aid programs courtesy of the incredible surplus of salmon that thrived and survived on their revived ocean pasture and were caught. Ask any of those kids whether they believe repurposing hundreds of millions of tonnes of CO2 into the fish they are surviving on was a good idea.

    While the tens of thousands of delegates in Paris are to be praised for their efforts, and raising the goal of spending trillions of dollars over coming yeas to control and repurpose CO2 is perhaps a good thing. Better is simply doing the lions share of the work right now at a cost of a mere millions of dollars per year. At a cost of those few millions of dollars per year many billions of tonnes of our menacing CO2 will be repurposed into ocean life itself. In the bargain billions of additional fish will swim into our nets and onto the plates of people in need helping to end world hunger. (Read more on my blog.)

  9. I am so glad so many people are aware of the weather modification that has been going on for some years. They are already spraying nano-aerosol particles from planes and this has been responsible for the constant ‘cloud’ cover which is affecting all life on this planet and is seriously counteractive to clean, green solar energy!

    We now have rickets back in the UK! Our trees are dying from fungal infections and because their root systems are shutting down in response to the heavy metals in our rain and soil – a double whammy against the planet! God help us all if they don’t stop this insanity!

    • Well my first thought on geoengineering is reforestation.

      See the Wikipedia entry re climate engineering:
      “Some carbon dioxide removal practices, such as planting of trees and bio-energy with carbon capture and storage projects, are underway.”

      Not extracting every bit of fossil fuel in the first place (fracking) is an obvious thing too.

  10. Seriously? Spraying highly neurotoxic amounts of barium, aluminum, strontium, etc. into our atmosphere is some kind of solution?? Will we all be given gas masks? Ridiculous and criminal if this happens.

  11. Chemtrails & Contrails ARE Causing Climate Change.
    NexRad Stations ARE Causing Climate Change.
    Ionospheric Heaters ARE Causing Climate Change.
    Artificial Cloud Creation IS Causing Climate Change.

    The Suggestion that Geoengineering is required to Stop Climate Change is a disgraceful statement.

    Geoengineering IS Causing Climate Change and has been for many decades.

    • Hear hear Fenton! Shocking that people even suggest geoengineering is an answer when we all know it is the CAUSE of all the climate problems we are facing today, and has been going on for years!

  12. Dan, I want to thank you and your Legal Planet colleagues like Ann Carlson for your dedication to informing and motivating us to make the right things happen with the required sense of urgency.

    A paramount problem that we must solve now is how Can We Adapt in Time?

  13. Geoengineering/climate engineering has already been deployed for many decades, and has ramped up significantly in the last few years – SRM/Solar Radiation Management. The consequences are evident and well documented, showing great harm to all living systems, including human health. See GeoEngineering Watch.

  14. Geoengineering is already being used…has been for many years…it has had serious implications on the planet & on our health. Saying it may be necessary, as if it hasn’t already been in use, is highly misleading.

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