3. Implementation Stage

At the point of implementation, when the technology moves from computer modeling and field testing to full scale deployment, certain matters of basic justice foreshadowed at earlier stages become urgent, and additional ethical concerns surface for the first time.

Procedural Justice

As an engineering project promising global impacts, some form of consent—at least from the representatives of those affected—would appear to be a non-negotiable requirement of just procedure. The call in the Oxford Principles for "governance before deployment" suggests that a formal governance procedure is a pre-requisite for any geoengineering deployment. Many pertinent questions will require stakeholder input, including questions concerning:

  • How to balance geoengineering efforts with mitigation efforts?  
  • How rapidly to ramp up the chosen technology (if it is scalable)?
  • How most effectively to evaluate the impacts?
  • What to set as targets?
  • Which political entity (or entities) should oversee the deployment?

Everyone on earth is a stakeholder in geoengineering. This suggests that procedural justice presents an enormous challenge. Furthermore, some stakeholders, including nonhuman nature and humans whom have not yet been born, are not even theoretically able to participate. As in the perfect moral storm of climate change, the institutions for resolving the procedural questions regarding geoengineering may simply not exist at this point.

Under conditions of an extreme planetary emergency—if such a state could be adequately defined—the requirements for procedural justice might end up being loosened. Hyping such an emergency is obviously in the interests of those who want to develop and test geoengineering now. For this reason, we should pay close attention to the way geoengineering is framed in the emerging cultural discourse.


McNaughton, P. & Szerszynski, B. (2013). Living the global social experiment: An analysis of public discourse on solar radiation management and its implications for governance. Global Environmental Change, 23(2), 465-474.

Scott, D. (2012). Insurance policy or technological fix? The ethical implications of framing solar radiation management. In C. J. Preston (Ed.), Engineering the Climate: The Ethics of Solar Radiation Management (pp. 151-168). Lanham, MD: Lexington Press.

Distributive Justice

The benefits and burdens of CDR and SRM, though somewhat variable and uncertain, require our best attempt at fair distribution. While geoengineering certainly promises net 'goods' over 'bads', a few very unlucky groups are likely to be made worse off.  Clearly there are concerns that the interests of the most powerful would be protected while those less powerful will get secondary consideration (if they are considered at all). Because those most vulnerable to adverse impacts are often also those least likely to have caused climate change, are often the least capable of adapting to it, and have the least input into geoengineering technologies, their interests are especially vulnerable to being neglected. This demands extreme vigilance and more conscience than has yet been shown if distributional justice is to be protected.

Determining when a future burden is the consequence of a ‘natural’ weather event, or of anthropogenic climate change, or of geoengineering will likely be next to impossible. Benefits and burdens are also likely to fall more upon future generations than on the present generation, making the demands of distributive justice extremely challenging to satisfy. With the various needs crossing geographical, generational, and species lines, it is hard to see how the challenges of distributive justice are going to be any more easily solvable than those of procedural justice.


Robock A. Will geoengineering with solar radiation management ever be used? Ethics, Policy, Environment 2012, 15:202–205.

Svoboda, T., Keller, K., Goes, M., Tuana, N. (2011). Sulfate aerosol geoengineering: the question of justice. Public Affairs Quarterly, 25(3), 157–180.


Wide-ranging 'incidental' concerns have been raised about the implementation of geoengineering. These concerns are made up of a number of unintended side-effects of efforts to reduce temperatures. For instance, if stratospheric aerosols are deployed, the ozone layer is likely to be damaged, leading to uncertain impacts on phytoplankton, plants, eyes, and skin. The diffuse light caused by intentional cloud and aerosol modifications will impact crop productivity and the effectiveness of photovoltaic panels. Stratospheric aerosols will cause whiter skies, which will pose challenges for astronomy and contribute to negative aesthetics. While many of these incidental impacts are undesirable, not all of them are obviously bad. More diffuse light can increase crop productivity, and the filtering effect of aerosols on ultra-violet light may decrease the incidence of skin cancers. Sunsets could also be more beautiful. Good or bad, these incidental impacts bear on human and environmental well-being and thus bring additional ethical considerations into play.

Different CDR technologies generate other concerns. Direct air capture will raise different questions than will a strategy like liming the oceans due to the way the materials deployed will be “unencapsulated” and thus capable of dispersing throughout the ecosystem. The scale of the required engineering for some CDR ideas is also a concern. Axon and Lubansky have estimated that direct air capture to remove the 30 gigatons of carbon dioxide emitted globally each year could require up to 180 gigatons of clean water, potentially impacting the water supply of 53 million people annually. While their calculations are rough, they illustrate how some CDR technologies, merely by the scale of the engineering required, are likely to create their own incidental environmental effects (Smith and Torn, 2013).


Axon, C. & Lubansky, A. (2012). Stripping CO2 from air requires largest industry ever. New Scientist 2859.

Preston, C. (2012). Ethics and geoengineering: reviewing the moral issues raised by solar radiation management and carbon dioxide removal.  Wiley Interdisciplinary Reviews: Climate Change, 4(1), 23-37.

Robock, A. (2008). Twenty reasons why geoengineering might be a bad idea. Bulletin of the Atomic Sciences, 64(2), 14–18.

Smith, L. J., & Torn, M. S. (2013). Ecological limits to terrestrial biological carbon dioxide removal. Climatic Change118(1), 89-103.