Solar Geoengineering ‘Too Uncertain to Go Ahead Yet,’ Expert Cautions

Progress to deploy solar engineering, experimental technology designed to protect the world against the impact of the changing climate, must pause, a former United Nations climate expert says, arguing that governments need to create “effective guardrails” against any unforeseen risks.

Janos Pasztor, who served as a UN assistant secretary-general on climate change, is using a speech to Arizona State University, broadast via Facebook Live by ASU LightWorks, 6:30-8pm Arizona time (9:30pm EDT – US Eastern Daylight Time) today, to warn the world that governments are largely ignoring the fundamental question of who should control geoengineering, and how.

There are widespread misgivings, both among scientists and more widely, about geoengineering, with many regarding it as at best a strategy of last resort to help to avoid calamitous climate change.

Mr Pasztor’s warning comes as researchers prepare for what is thought to be the world’s first outdoor experiment on stratospheric aerosol injection (SAI), one type of solar geoengineering. The test is due to take place later this year over Arizona.

Pasztor heads the Carnegie Climate Geoengineering Governance Initiative (C2G2),  an initiative of the New York-based Carnegie Council for Ethics in International Affairs. The Initiative wants solar geoengineering deployment to be delayed until the risks and potential benefits are better known and governance frameworks are agreed.

“Some time within the next year, we may see the world’s first outdoor experiment on stratospheric aerosol injection take place here in the skies above Arizona, yet for the most part governments are not aware of, nor addressing, the profound governance issues this poses,” Mr Pasztor says.

“We urgently need an open, inclusive discussion on how the world will research and govern solar geoengineering. Otherwise we could be in danger of events overtaking society’s capacity to respond prudently and effectively.”

Solar geoengineering does not remove carbon from the atmosphere, and so it can be used only to supplement action to reduce greenhouse gas emissions: it can never replace that action. Many risks and unknowns remain, Pasztor says, including possible harm to the environment, and to justice, geopolitical concerns and governance.

With SAI aerosols are sprayed into the stratosphere to reflect the sun’s radiation and cool the earth fast. It is still in its early stages, and scientists say it will take another 15 to 20 years for the technology to be developed fully.

Too soon to decide

Any eventual full-scale deployment of technology of this sort would have planet-wide effects and pose profound ethical and governance challenges, C2G2 says. Pasztor says the risks and potential benefits of SAI are not yet understood well enough for policymakers to reach informed decisions.

This year’s planned experiment, called SCoPEx (Stratospheric Controlled Perturbation Experiment) is run by a Harvard University research group, which says the physical risks posed by the quantity of aerosols to be released during SCoPEx will be hundreds of times smaller than during a transatlantic flight by a commercial airliner.

Even so, Pasztor says, the governance of SCoPEx will probably set important precedents. “As solar geoengineering moves from the lab to outdoor experiments, crucial questions remain unanswered,” he argues.

“How does this experiment acquire legitimacy from other scientists? Do civil society groups and the public, including those located in the area of the experiment, have a say? What are the ramifications for other proposed experiments in this country or in other countries?”

Priority for cuts

So far, he says, many governments and civil society groups have shied away from the need to create governance for the new technology, or have not been aware of it. One common concern is that discussing geoengineering could distract society from concentrating on cutting carbon dioxide emissions.

Other geoengineering ideas, which may be nearing testing, include proposals to refreeze parts of the Arctic and to brighten clouds at sea.

“There’s no question we must accelerate efforts to rapidly reduce global emissions, whilst at the same time remaining open to the possibility that other approaches may also be needed if we are to limit some of the adverse impacts of global warming”, Pasztor says.

“Public policy needs to address very legitimate safety, human rights and accountability issues, as well as concern for future generations.

“Getting this right is a challenge that affects all humanity, and needs to be addressed through discussions that include all sectors of society. It’s critical the world addresses this issue as soon as possible.”