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by Mark Turner / August 17, 2018

A vibrant debate around Nature’s recent paper on solar radiation management and crop yields offers some important insights into how the public conversation around geoengineering could progress, and how it might be improved.

For a niche topic, the media coverage around the paper was significant, inspiring articles by Reuters, Wired, the Washington Post, Gizmodo and others. So what were its findings, that caused such interest?

Quoting from the paper’s abstract, we learn that “solar radiation management—if deployed using stratospheric sulfate aerosols similar to those emitted by the volcanic eruptions it seeks to mimic—would, on net, attenuate little of the global agricultural damage from climate change.”

Yet many of the headlines told a rather more dramatic story: “Reflecting sun’s rays would cause crops to fail, scientists warn”, or “A volcano-inspired weapon to fix climate change is a terrible idea”, and – courtesy of the Daily Mail – “Blocking sunlight to cool Earth will NOT save humanity: Particles injected into the atmosphere may fix global warming but they could also kill off our crops by starving them of UV light.”

Some of these, critics argued, misrepresented its findings, by suggesting that solar geoengineering would, on balance, damage crops. Either way, and perhaps regardless of the merits of the piece itself, a potentially important narrative appears to have been created.

What is the takeaway for policy makers trying to make sense of this all? Are there any clear lessons we might learn from this paper, and the subsequent debate? Can we now conclude that ‘solar geoengineering won’t work’, or is this just one tiny piece of a much larger puzzle, many of whose pieces we haven’t even begun to imagine? Here are some initial thoughts.

Public narratives at this early stage can have a big impact: we need more voices

Media coverage of geoengineering tends to come in spikes. At this relatively early stage in the public conversation, these spikes can play an outsize role in shaping and defining the narrative. Once an idea is out there, it becomes that much harder to challenge it.

Similarly notable moments this year followed papers on low-cost Direct Air Capture, and on the risk of Solar Geoengineering for biodiversity. These also led to frames that may come to define the geoengineering conversation, such as “we can affordably suck CO₂ out the air to tackle climate change” or “solar geoengineering would be too dangerous for wildlife”.

What makes one narrative succeed as opposed to others? Elements can include timing, accessible headlines, and the dark arts of public relations, as well, of course, as the intrinsic merits of the paper. But these factors can mask nuances and critiques, and may disadvantage other voices, including from people in the developed world.

Right now, much of the geoengineering conversation is dominated by Western scientists writing papers – sometimes in influential journals. As international public policy-makers get serious about exploring the potential (or not) for large-scale carbon removal or solar geoengineering, a greater variety of views needs a hearing.

Good journalists can help address this and will be aware of the importance of early framing. But they are also subject to the news cycle. We need other ways to help generalists better navigate these evolving narratives.

People want to know the real-world consequences of geoengineering

Society thirsts for more information on how geoengineering will affect real-world outcomes: food, health, jobs, security. That is why any analytical framework must consider the effects of these technologies not just on CO₂ concentrations and temperature goals, or even on agricultural production, but rather on the totality of Sustainable Development – and beyond.

In a recent report, C2G2 called for a more systematic examination of effects on all the 17 Sustainable Development Goals (SDGs). We analysed what studies already exist and called for more research to fill the gaps. Papers like the Nature study on crop yields can play an important part in filling in the puzzle.

But this is just a start. Effects on one aspect of Sustainable Development can create a cascade of consequences for others. Food insecurity, for example, can drive migration, which in turn can exacerbate ethnic tensions and lead to conflict.

Whether through direct effects, or through the perception of those effects (in practice it may not matter if a geoengineering technology is proven to cause something, or people simply assume it does), these technologies are likely to have long-lasting and often unforseeable security and geopolitical impacts.

The deep complexity of our climate and economic system means we need to assess the effects of these proposed technologies on the ecosystem writ large. This is no small task. Changing even one variable – such how diffused sunlight affects crop yields – could have knock-on effects that we haven’t even begun to imagine.

Building up a comprehensive picture, step by step

From scientists to entrepreneurs, NGOs to policy-makers, actors need to consider the impact of these technologies in their totality. We can imagine a kind of cinematic camera zoom out, which reveals more and more of the picture with each subsequent step.

The early focus will be upon individual carbon removal and solar geoengineering technologies, judged on their own merits against temperature. Pulling back, we consider their interaction with emission reductions and adaptation activities, in the context of a warming world.

Pulling back further, we examine their impacts against the Sustainable Development Goals, and finally go full wide-angle to reveal the vast potential for knock-on effects, including on geopolitics and global security.

Doing this right is a daunting task. In practice, our ability to conduct this holistic level of analysis may be severely limited, and in some cases may be impossible.

But that doesn’t mean we shouldn’t start trying – and soon, before a few powerfully influential articles create long-lasting frames, based only a few pieces of the puzzle. And when we do so, we need to make sure we are taking account of a much more diverse set of views than currently dominates the news.