We sought both commonalities and variations in participants’ sense-making across the focus groups. Surprisingly, we found clear commonalities concerning initial affective reactions to information about climate engineering, the participants’ reasoning and explanations regarding their reactions, as well as the participants’ final positions regarding climate engineering options.
Unintended side effects and limits of human control of nature
When the moderators first mentioned climate engineering, recurrent initial reactions were expressed by using the terms ‘scary’, ‘risky’ and ‘science fiction’. With a few exceptions—particularly in some of the Japanese groups—participants were largely critical of the prospect of climate engineering, sometimes reacting with disbelief or nervous laughter at the idea. One common theme in the focus group discussions related to the risk of unintended side effects as a consequence of climate engineering. Participants claimed that introducing climate engineering might lead to humankind’s losing control of what it had started; despite good intentions to alleviate the impacts of climate change, deliberate large-scale manipulation of the global climate might have unforeseen negative consequences, making the situation even worse, especially for already vulnerable groups of people. In particular, participants expressed their fear that climate engineering might cause changes in ecosystem balance.
A common sense-making strategy in all countries was the use of analogies to advocate particular viewpoints on climate engineering. While the analogies were coloured by the national and cultural contexts in which they were expressed, they nevertheless expressed similar arguments. Participants would make analogies to the introduction of new species such as toads in Australia, Canada geese in Sweden or possums in New Zealand, arguing that what was done with good intentions, i.e. introducing new species into the fauna, ended in loss of control of the negative effects of these new species. Similarly, climate engineering was seen as possibly generating larger problems than the one it was meant to solve. An example illustrating this line of reasoning comes from the group of Japanese male middle-aged participants:
Perhaps it [climate engineering] will be technically doable, can be realized one day, but because some unintended effects will result, it will eventually end in vain. … Because all train lines are connected, one line to another, if a fatal accident happens in Gunma [north of Tokyo], a train running around Atami [south of Tokyo] will be stopped. So, you know, if Japan cools down, heat waves could hit the USA – such kinds of odd phenomena could happen. … It’s too big to control. You know, intuitively, I feel it’s impossible. (Japan, Group D)
By making analogies with how the Tokyo train lines are interconnected and how accidents in one train line will affect other distant train lines, the participant in Example 1 suggests that climate engineering may result in less rather than more control over the climate, with unintended consequences occurring far beyond national borders.
Other examples of loss of control include analogies with building dams (USA), the use of DDT, or the dumping of industrial waste in the oceans (Sweden). In the effort to solve one problem, another bigger problem was created due to a lack of knowledge of negative side effects—or as one New Zealand participant put it, such technologies are like ‘shooting in the dark’ (Group A). In the words of one US participant, ‘you think about everything from building dams to introducing invasive plants to control another plant, introducing predators. It always goes wrong’ (Group B). Analogies were also repeatedly made with other large-scale, high-stake technologies, in particular nuclear power, where uncertainties and risks of unintended negative side effects were seen as major problems. Such analogies reinforce the view of climate engineering as risky and uncontrollable. Commonly, participants embraced the view that humanity should not intervene in complex systems that it cannot control or understand (cf. Corner et al. 2013).
It should be noted, however, that although most focus group participants reacted with fear and scepticism to the idea of climate engineering, quite a few participants in the Japanese groups deviated from the general critical stance towards climate engineering, and displayed enthusiasm for technological development in general (for details, see Asayama et al. 2017). To explain their optimism, these participants used analogies with recent technology innovations such as mobile phones or LED light bulbs to advocate for accelerated development of new technologies. Nonetheless, the focus groups making these supportive utterances also articulated most of the other themes presented through Sections 4.1–4.5.
Treating the symptoms rather than the cause
In the focus group discussions, participants often categorised climate engineering as merely treating symptoms, or as an extreme end-of-pipe solution that fails to address the core problem of anthropogenic climate change. The idea of attempting to remedy damage to the global climate system by developing large-scale technologies for global climate control was seen by many participants as a short-sighted solution, constituting a mere distraction from mitigation actions and lifestyle changes (see Section 4.3) and taking resources from the development of low-carbon energy technologies that should instead be prioritised.
Climate engineering was also seen as a way of ‘shifting the problem’ (NZ, Group B), with the risk of causing ‘environmental problems later that we are going to try and engineer around again’ (US, Group A). An ethical dimension was raised in several groups, relating to unequal exposure not only to the impacts of climate change but also to the risks of climate engineering experimental research. This line of reasoning is illustrated by the following example from the New Zealand indigenous Māori group:
Which country is going to volunteer to be the experimental country? Usually it’s the ones that probably can’t afford it. Rather than doing that, why is there resistance to actually actioning some of the practical solutions that have been offered to them now … and so rather than spending more money, because that really just adds to the cost globally – more money, more time, more delay – and while they are doing that our Pacific Islands have a high risk of being underwater before that is even completed when we have immediate solutions at hand. (New Zealand, Group E)
Example 2 summarises several of the thoughts frequently raised across the focus groups: the issue of climate (in)justice (cf. McLaren et al. 2016), outlining a scenario in which the poorest, already most vulnerable groups might become the subjects of climate engineering experimentation, and the risk that investing time and money in climate engineering research would displace investments in mitigation and adaptation (cf. Burns et al. 2016).
In discussing climate engineering as an end-of-pipe measure failing to address the core problem of climate change, a common strategy was to use analogies and metaphorical descriptions, particularly from medicine, such as ‘you can’t just plaster [i.e. bandage] the problem, you need to, like, get closer to the cause’ (NZ, Group B), describing climate engineering as ‘a blood pressure pill but no change of lifestyles’ (NZ, Group B), or comparing climate engineering to cancer treatments that eventually make things worse (Japan, Group F; Sweden, Group C). Another analogy developed in the US senior citizen group (C) further illustrates this theme, with one participant saying that climate engineering was like ‘taking the ambulance to the bottom of the cliff rather than eliminating the problem or working on the problem’, reinforcing the ‘moral hazard’ argument that climate engineering constitutes a dangerous distraction rather than a solution to the climate crisis.
Need for changes in lifestyles and consumption patterns
The third recurrent theme was that lifestyle changes are necessary in rich countries due to overconsumption and a way of life that exhausts natural resources and destroys life-support conditions for humans and non-humans. Participants argued that the stresses on ecosystems could not continue, and that climate engineering was, in this context, just another way of maintaining business as usual. By making this categorization, participants concluded that climate engineering should be rejected in favour of systemic changes in energy production, transportation and consumer goods production. As one New Zealand Māori participant pointed out, ‘the economic system does not work – [it] all needs to change drastically. A whole different thinking has to come out of it’ (Group E). Similarly, one Swedish retiree asked: ‘When will we reach that level where we understand that much less is enough?’ (Group H). Another example comes from the Japanese group of middle-aged men, one of whom claimed that ‘climate engineering sounds like we keep going along our current path by brute force, not cutting CO2 emissions, which are too high’ (Group D).
Some participants expressed doubts as to whether people would voluntarily change their lifestyles, but when asked to choose between mitigation, adaptation and climate engineering, most participants strongly advocated mitigation on the individual and collective levels. Participants also claimed it was necessary to decrease consumption, to settle for less, both individually and collectively, and to orient oneself towards a less materialistic way of life. Several participants in the US mixed-age group argued that even though they were difficult, these changes were seen as imperative that people had come together to solve:
We learned how the American people and probably the world … came together for the Second World War. Like we dropped everything and we joined the solution – what we thought that was at the time. And I think that by creating an environment of inclusiveness and team spirit, that is the way to actually motivate us to join the solution rather than being a part of the problem. (USA, group D)
By making an analogy to the sense of urgency during World War II, Example 3 illustrates the recurrent viewpoint that emergencies can lead to increased emphasis on structural and individual change and action. When comparing various responses to climate change, most participants from all four countries preferred mitigation to either adaptation or climate engineering. For example, one Japanese female senior made the argument for mitigation options through an analogy with car driving, arguing that ‘it's the same with car driving – if you brake suddenly, you will fall down; if you try to stop it [climate change] artificially all of a sudden, it would be a bit of a stretch … what is more important is to prevent car accidents from happening. It’s better to take actions that make it [climate engineering] unneeded’ (Group E).
This indicates that for the focus group participants, climate engineering seemed to have a ‘reverse moral hazard’ effect (Reynolds 2015), i.e. increased willingness to consider and even advocate behavioural changes, rather than being deterred by the introduction of new technologies for large-scale climate control. Leaving no room for doubts about what is at stake, climate engineering seemed to compel participants to take a stand regarding behavioural patterns in the rich countries that usually led to critical re-evaluation of their own lifestyles and the consumption culture permeating their parts of the world (cf. Corner and Pidgeon 2010; Merk et al. 2016; Sütterlin and Siegrist 2016).
The need for political solutions
A fourth recurrent theme centred on the concern that national and international policies may fail to achieve substantial reductions in greenhouse gas emissions. Individual politicians, national governments and international political organisations, such as the UN, were seen as unable to tackle climate change and agree on measures that really make a difference. Pessimism regarding the ongoing UN process dominated initial parts of the conversations across all focus groups.Footnote 3 However, confronted with the idea of climate engineering, participants in most groups (although seldom in the Japanese groups) strongly emphasised that they preferred political solutions rather than large-scale technologies for controlling global climate. When climate engineering was introduced into the discussions as an alternative measure, participants re-evaluated the political measures and claimed that national governments and international political organisations have the responsibility to take action against climate change. Participants found the outlook of a climate-engineered planet so frightening that it prompted participants to claim that solutions, after all, must be political, and that political failure was unacceptable. The following quote from one Swedish group of middle-aged citizens illustrates this reasoning:
One must not accept the statement that political solutions are not a way forward, but they are a path that you are not allowed to give up on. Maybe you have to surrender and fall back on something … But I can’t see how that would imply that you should stop the attempts already ongoing today. (Sweden, Group C)
The participant quoted in Example 4 emphasises that political solutions should be prioritised. The metaphor of ‘path’ used to advocate political agreements suggests that humanity can still choose to follow a particular strategy and that when one stops trusting in politics, one is already in a state of ‘surrender’. Meanwhile, the metaphor of ‘surrender’ was used to make sense of what climate engineering implies. This ‘surrender’ metaphor contributed to categorising climate engineering as the opposite of a preferred option (i.e. mitigation) to tackle climate change, i.e. as a measure one reluctantly may have to fall back on, if all other possibilities are exhausted.
Even the participants who were open to climate engineering as a last resort (see Section 4.5), reiterated the need for international political regulation and the possibility of reaching international political agreement as a prerequisite for climate engineering governance. If climate engineering should be necessary in a future emergency, they claimed that it should be governed by international political organisations and not handed over to private corporations or superpowers such as China or the USA.
In the Japanese focus groups, the discussions differed somewhat, in that the idea of climate engineering did not lead to re-evaluation of the role of politics. While some Japanese participants explicitly said that mitigation should be prioritised, this did not necessarily lead to re-evaluation of the role of politics; rather, the participants identified the radical change of individual wasteful lifestyles as a primary course of action (see Section 4.3).
Notwithstanding, most participants saw climate engineering as yet another scary concept underlining the seriousness of the situation that world politics must address, and climate engineering was in this context interpreted as the final wake-up call.
Keeping the door ajar for all options
When the focus group moderators first introduced climate engineering, spontaneous reactions of fear and anxiety were widespread in most groups (see Section 4.1). However, these initial reactions were sometimes gradually renegotiated and at times ended in ‘conditional support’ for climate engineering research or the stance that, one should keep the door ajar for all options, including climate engineering. One example illustrating this stance comes from the Japanese group of middle-aged men, in which one participant claimed that it was not an ‘either/or’ argument, as to whether we should consider climate engineering an option, but a ‘both/and’ argument that we should pursue all available options. The participant summarised the options as follows: ‘only mitigation’ is the ideal way, adaptation is a pragmatic approach and climate engineering could be a last-resort option.
The focus groups recurrently debated whether the risks of catastrophic climate change constitute a case for climate engineering. The moderators’ introduction of the climate emergency argument marked a turning point in some of the groups, leading participants to advocate research into climate engineering, despite their initial criticism. Participants in the Young Professionals group from New Zealand highlight this theme by using the ‘tipping point’ and ‘safety net’ metaphors:
W18: If you can prove you’re past the tipping point, then I guess then there’s nothing else you can do, apart from something like this.
W19: I believe that there is value in doing further research. It’s quite good to know that research has been done and there could be something potentially made of this, so when a disaster, like crazy, happens in 2025 we have something to fall back on. Sort of a little bit of a safety net. (New Zealand, Group A)
Example 5 illustrates a line of reasoning in which support for climate engineering research was rationalised as humanity’s last resort and—after set against the risks of climate change—as ‘the lesser of two evils’ (cf. Gardiner 2010).
Various reactions across the focus groups related to ‘the climate emergency’ argument. The most common response was for participants to emphasise the need for more serious efforts at mitigation and lifestyle changes (see Section 4.3, 4.4). In several cases, however, especially in the Japanese groups, the severity of the climate crisis seemed to legitimise support for research on climate engineering. A recurring stance in this regard was that humanity must explore all available options including climate engineering, despite its ethical, scientific and political downsides. Or, to quote an analogy employed by one US participant, ‘it [climate engineering] is something that really needs to be looked at seriously, but it's kind of like nuclear weapons you know, it's like spend a lot of research in brain power and money trying to develop something that you never want to use’ (Group D).
Participants seldom presented arguments for deployment of climate engineering, however. It is also noteworthy that support for research was usually heavily conditioned; for example, technology development must not be handed to big corporations, countries or other organisations considered able to weaponise climate engineering (cf. Macnaghten and Szerszynski 2013).