Climate change mitigation requires large-scale lifestyle changes by individuals and public support for transformative climate policies. The UK Climate Change Committee estimates that at least 32 % of emissions reductions will be needed by 2035. relies on changes in individual and household behavior. A recent eight-week field experiment study, conducted using a specially designed smartphone app, explored how moral appeals can influence everyday behavior and civic engagement in the fight against climate change.

Methodology and study design

The study included 156 participants from the general UK population who were randomly assigned to a control or intervention group. Over eight weeks (mid-October to mid-December 2023), participants recorded their climate-impacting behaviours daily across six domains (car use, flying, energy use, heating, food and non-food purchases of new items), measured in CO2 equivalents. They also recorded their civic and political activity, such as information seeking, climate change discussions and direct contact with political representatives.

A key innovation was the development of a proprietary mobile application, “Climate Champ,” which provided participants with visualization of their individual carbon footprint and civic climate positivity score. Participants in the intervention group were exposed to daily, pre-tested, AI-generated moral appeals that were displayed when the app was opened. These appeals were based on Moral Foundations Theory, specifically on moral foundations related to care and justice, which are positively associated with willingness to contribute to climate change mitigation. The control group was not shown any such messages.

Key Findings: Carbon Footprint Reduction and Civic Engagement

The study confirmed that exposure to moral appeals led to an overall reduction in carbon footprint in the intervention group, especially in the areas heating, food and consumptionDespite the seasonal increase in energy consumption in the colder months, the increase in carbon footprint in the intervention group was more modest, leading to an overall lower carbon footprint in this group (approximately 19 kg CO2e per day at the end of the study).

In the area heating the effect was most pronounced, which participants attributed to greater perceived control over this behavior and potential cost savings. Carbon footprint from food (especially meat and dairy products) began to decline slightly in the intervention group after a few weeks, as participants learned to perceive the impact of their diet. A decrease was also noted in consumption new non-food items, although with greater individual variability.

However, no significant difference was noted in some domains. This is true for electricity consumption and flyingA surprising finding was that moral appeals led to some intervention group participants increasing the carbon footprint from car use, especially those who distinguished themselves egoistic valuesThis “backlash” effect suggests that individual circumstances and values play a key role, with more than half of the participants in the intervention group having the predicted negative impact on driving emissions.

Most importantly, the study confirmed the second main hypothesis: Exposure to moral appeals significantly increased civic and political climate engagement scores. Participants in the intervention group had a 34% higher rate of engagement in civic and political climate actions. These actions included seeking information, discussing climate change, signing petitions, donating, joining climate groups, and even participating in climate protests. This effect was noticeable across the political spectrum, including those who politically lean towards the center and right, which is a significant finding.

Important factors and conclusions

The study also found that a stronger sense of personal agency (ability to act) enhanced the impact of moral appeals on civic and political engagement. Conversely, emotional state and perception of social norms had no significant impact on carbon footprint changes or civic engagement.

These findings demonstrate that Moral arguments based on the moral foundations of care and justice can effectively motivate people to make lifestyle changes and engage in active climate citizenship., even among more politically conservative individuals. The study suggests that Moral Foundations Theory needs to be integrated into the COM-B model of behavior change, as morality, understood as socially shared foundations, can be a stronger motivator than personal standards alone. The findings also highlight the need for systemic change, particularly in the transportation sector, where investment in public transportation is needed to enable behavioral transformation. JRi