International CO2 emissions reduction commitments are insufficient to avert damaging global warming and imperil a sustainable future. Climate engineering approaches are increasingly proposed as near-term intervention strategies, but deployment of these controversial techniques will require careful engagement with and the support of the public. New quantitative measurements of public perceptions for six climate engineering approaches show that the public of the United Kingdom (UK), United States (US), Australia (AU), and New Zealand (NZ) continue to have little knowledge of climate engineering. All approaches are regarded unfavourably, albeit less so for Carbon Dioxide Removal (CDR) than Solar Radiation Management (SRM). Knowledge and perceptions are remarkably similar between countries although UK and US respondents are more favourable towards SRM and UK respondents are more favourable towards CDR. Stratospheric Aerosol Injection is the most negatively perceived approach. Support for small-scale trials is also higher for CDR approaches than SRM. Statistical analyses yield mixed relationships between perceptions of climate engineering and age, political affiliation and pro-ecological views. Thus far, attempts to engage the public with climate engineering have seen little change over time and consequently, there is growing urgency to facilitate careful citizen deliberation using objective and instructive information about climate engineering.

Researchers disagree on the extent that brief survey methods accurately reflect citizens’ opinions of unfamiliar scientific concepts. We examine whether encouraging participants to engage in more reflective thinking affects their perceptions of emerging climate technologies. Drawing on dual-process theories of reasoning, we apply experimental manipulations to encourage fast, intuitive thinking or slow, reflective thinking when responding to an online survey. Similarities in concept evaluation time between the Control and the Intuitive treatment groups indicates that citizens default to fast intuitive judgements to form opinions. However, despite a successful manipulation check, the reflective treatment group did not show any substantively different results. Therefore, encouraging additional thinking is unlikely to shift public perceptions. Post hoc analysis suggests participants with stronger views may nonetheless take more time to consider their response, without prompting. These findings support the validity of surveys as a method for eliciting stable and meaningful public perceptions of emerging technologies.

Although shipping is the most energy efficient method of transporting trade goods it is held accountable for 2–3% of global greenhouse gas (GHG) emissions. The shipping industry is exploring pathways to carbon–neutral fuels to help eliminate GHG emissions by 2050. To date research on alternative fuels has not considered public opinion; it remains unclear whether the public will support alternative shipping fuels, or whether public opposition might prevent or defer their deployment. To fill this knowledge gap and help the industry and policy makers arrive at publicly acceptable decisions, our research examines UK public perceptions of six shipping fuels using a mixed-method approach. Our findings reveal that biofuels and hydrogen are clearly favoured, owing to biofuel’s perceived low risk and hydrogen’s lack of negative by-products. Perceptions of liquid natural gas are somewhat positive, suggesting that it provides an acceptable near-term option while other fuels are developed. Despite lingering stigma, nuclear is preferred over the incumbent heavy fuel oil, though both are perceived negatively. However, the UK public strongly dislike ammonia, perceiving it as unproven, risky, and lacking availability. A third support use of alternative shipping fuels, with support greater from those living near ports—a “yes in my back yard” effect. The results demonstrate that different alternative fuels are likely to elicit different public reactions as they become more widely known and show how the overall evaluations arise from specific positive or negative associations with each fuel.