Large Language Models Enable Personalized Nudges to Promote Carbon Offsetting Among Air Travellers

Abstract: Nudge strategies are effective tools for promoting sustainable behaviour, but their impact depends on individual preferences. By emulating human decision-making, LLMs offer a cost-effective route for tailoring nudges without extensive behavioural datasets, yet this potential remains unexplored. Focusing on aviation, we use LLMs to design personalized decoy-based nudge strategies that encourage air travellers to voluntarily offset CO$_2$ emissions from flights, and validate their efficacy through 3495 surveys from China, Germany, India, Singapore, and the United States. Results show that LLM-informed personalized nudges are more effective than uniform settings, raising offsetting rates by 3-7$\%$ and yielding an additional 2.3 million tonnes of CO$_2$ mitigated annually in aviation. This improvement is driven primarily by increased participation among sceptical travellers with low trust in offset programmes. Our study highlights the potential of LLM-driven personalized nudging strategies for boosting offsetting behaviours to accelerate aviation decarbonization.