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Guest post by Shuchi Talati, Geoengineering Research, Governance, and Public Engagement Fellow, Union of Concerned Scientists / May 2, 2019

[The views of guest post authors are their own. C2G2 does not necessarily endorse the opinions stated in guest posts. We do, however, encourage a constructive conversation involving multiple viewpoints and voices.]

Climate change threatens public health, food security, water availability, and national security – just to name a few.

Dramatic reductions in emissions and increased investments in measures to adapt to unavoidable impacts are essential but may not be enough to limit severe climate risks—and to date, these actions have fallen far short of what is needed.

Some researchers are proposing to do experiments to also test the potential feasibility and effectiveness of solar geoengineering (also known as solar radiation modification) approaches to help limit climate change, while recognizing that mitigation and adaptation must remain our first-line solutions.

While solar geoengineering could limit some harmful climate impacts, these approaches could also have adverse impacts and would not address the root cause of climate change: rising emissions of heat-trapping gases from burning fossil fuels – or some of the resulting impacts, such as ocean acidification. We also know very little about how it could impact regional weather patterns, global politics, and efforts to curb global warming emissions.

Should solar geoengineering experiments proceed and, if so, under what conditions?

The Union of Concerned Scientists (UCS) is now taking a hard look at whether and under what conditions outdoor experiments in solar geoengineering should go forward. UCS is a nonprofit organization dedicated to using science to address global problems, using both technical analysis and advocacy to achieve solutions. Complicated issues like geoengineering are ones that we try to grapple with to help encourage equitable and sustainable outcomes.

When referring to solar geoengineering experiments, we are specifically focused on marine cloud brightening (MCB) and stratospheric aerosol injection (SAI). Injecting aerosols simulates what happens during volcanic eruptions, where volcanoes emit small particles that reflect sunlight and lead to cooling when they reach the atmosphere. Cloud brightening would use sea salt to stimulate cloud formation over the ocean to also help reflect sunlight. This is especially important now as outdoor research in both MCB and SAI has been proposed.

A group of researchers at Harvard University are proposing to conduct the first known stratospheric experiment. The Stratospheric Controlled Perturbation Experiment (SCoPEx) is a small-scale experiment proposed to take place in the Southwest United States in which a balloon would disperse about a kilogram of calcium carbonate aerosols in the atmosphere that researchers would monitor. At the same time, the Australian government is funding a feasibility study into MCB to determine whether reflecting sunlight could help protect the Great Barrier Reef.

While small in scale, the precedent these experiments would set are extremely important. What will governance look like for future experiments? Who gets to participate in the decision-making process? Would they accelerate interest in larger and riskier outdoor experiments?

While MCB and SAI are very different methods of solar geoengineering, both have transboundary environmental and social impacts, which makes outdoor experimentation a difficult subject to address. This transboundary nature makes the line between small- and large-scale research a murky but critical one, necessitating different approaches and responses.

UCS defines large scale experiments as those of sufficiently large scale to have a measurable impact on Earth’s surface climate. We issued a position statement in February 2019 that states firm opposition to large-scale testing, and we outline key pre-conditions that must be met before small-scale experiments are undertaken to ensure that these efforts are done safely and transparently.

Governance & Engagement

We believe that a fundamental aspect of decision-making around research is that there should be substantial leadership from nations and communities most vulnerable to climate change.

Those most vulnerable should have a meaningful voice not only in decision making, but also in helping to shape research priorities. Diverse views prompt questions and ideas that discussions largely confined to select spaces in the global north cannot presume to know. This requires methodical engagement of a cross section of global stakeholders early in the research process.

In practice, determining what this process looks like and how to effectively create an environment where stakeholders are heard will require substantial forethought and input from ethics and social science experts. UCS is launching research into this space, with hope that we can contribute to creating an effective model and guidelines that could be implemented for future experiments.

Additionally, researchers should support independent governance mechanisms for such research projects. Without an independent body, oversight and transparency won’t have public trust.

Significantly, UCS Director of Science and Policy Peter Frumhoff helped establish and shaped the role for an independent advisory committee for SCoPEx. The committee has been charged with advising the project on the “need, objectives and possible formats for stakeholder engagement.”

If it functions as intended, the committee will ensure transparency and inclusion as well assess the risks around the experiment before it makes a decision on whether or not it will take place. The process of this committee will be an important one to follow once it begins its work.

Another important piece of research governance is around funding. While it is within the rights of a researcher to accept funds from a broad range of entities, including from governments and private organizations, being transparent around where these funds are coming from is a more critical issue for geoengineering.

To help address concerns around moral hazard, researchers should only accept funding only from entities and governments that also unequivocally support mitigation and adaptation measures to address the root of the climate change problem.

The Future Landscape

Given uncertainties and risks around it, solar geoengineering is problematic. Some are opposed to experiments such as SCoPEx out of concern that it will legitimize solar geoengineering and give the United States, other nations, and fossil fuel companies the incentive to keep emitting global warming gases unabated. These are valid fears.

Mitigation and adaptation are and must remain unquestionably the first-line solutions to climate change. However, it is becoming increasingly clear that our failure to take strong action to date means that the risks we face from climate change won’t be limited by reducing emissions alone.

We will have to invest aggressively in adaptation measures. And we must also develop an understanding of the potential feasibility and risks associated with solar geoengineering, should those become seriously considered or be employed by other actors. At such a moment, the scientific and societal understanding of the positive and negative consequences of regional or global deployment must be robust to inform such considerations.

As we state in our position statement, “A precautionary approach to grave climate risks is one in which society invests in developing a careful understanding of all possible climate response options, including ones that themselves pose substantial risks and uncertainties.”

This blog was adapted from a post on the UCS blog about geoengineering, which can be found here.