Mitigating climate change requires a collaborative effort, with experts from diverse fields coming together to develop effective solutions. The project behind this paper embodies this sentiment, leveraging a novel interdisciplinary approach to design and test which interventions are most effective in stimulating climate action. In the paper, we share the data collected by The International Climate Psychology Collaboration, the largest experiment to date conducted in climate psychology. We aimed to address the limitations of previous climate change mitigation research, which has often been limited to WEIRD (Western, Educated, Industrialized, Rich, and Democratic) samples and relied on correlational methods. To do so we sought to develop and test interventions designed to promote climate change mitigation in as many countries as possible. This resulted in one of the most diverse studies ever conducted on climate change beliefs and behaviour - involving 258 researchers from around the world who collected data from nearly 60,000 participants across 63 countries.

Figure 1.  Data distributions. The number of participants in each of the 63 countries represented in the sample

Collaborative Efforts: Crowd-sourced Intervention Development 

The success of this experiment was largely due to its collaborative nature. Numerous researchers from across the globe contributed to the project through a unique crowdsourcing approach. The core team called for proposals, inviting experts to design interventions that could be tested globally. After receiving 36 submissions, 11 interventions were chosen based on their theoretical grounding and practical feasibility.  The interventions leveraged different psychological techniques ranging from promoting social norms to invoking patriotic duty. Each intervention was designed to be administered within a short timeframe and to work effectively across diverse cultural contexts. By leveraging the expertise of a wide range of collaborators, we demonstrated how interdisciplinary and cross-border cooperation can be instrumental in developing ways to tackle global challenges like climate change.

Table 1. Interventions tested in the dataset and their description.

For those interested in seeing how the interventions looked, we provide a link to the USA version of them:  https://fpse.qualtrics.com/jfe/form/SV_cGtJw42i4jVqv5A

What Variables We Measured in the Dataset

We tested the effects of the interventions on four primary outcome variables: climate change belief, support for climate mitigation policies, willingness to share climate-relevant information on social media, and performance on a pro-environmental behavior task (Vlasceanu et al., 2024). The pro-environmental behavior task measured participants' willingness to exert time and cognitive effort in exchange for a donation to an environmental organisation. The organisation we selected was Eden Reforestation Project, an NGO that works in developing countries to rebuild natural landscapes destroyed by deforestation. As a result of the participants' efforts, we planted 333,333 trees in collaboration with the Eden Reforestation Project.

In addition to the primary outcomes, we collected data on various demographics and other variables of interest that might influence climate change attitudes and behaviour. In the control group we additionally measured psychological factors such as trust in climate scientists, environmentalist identity, and second-order climate beliefs. Moreover, several of the intervention conditions included a number of additional climate-relevant variables. These measures can be used to explore the factors that relate to climate change beliefs and actions across the globe. 

Opportunities for Future Work

The data collected offer a rich foundation for further exploration into the cross-cultural differences in climate action and how demographic factors such as age, political ideology, and socioeconomic status influence responses to interventions. For example, researchers assessed the differential role of these interventions across the ideological divide (Berkebile-Weinberg et al., 2024). Additionally, this data can be combined with data from other sources, for example nation-level metrics of human development and climate risk, to investigate the role of both individual and nation-level predictors of climate action (Todorova et al., 2024). The variety of additional measures collected in some of the experimental conditions offers countless opportunities to answer a variety of different questions, e.g. on the role of identity or pluralistic ignorance about belief in climate change in shaping climate action. Moreover, the innovative approach to crowd-source intervention development provides a model for future global collaborations in the behavioral sciences. We suggest expanding on the interventions by tailoring them to the respective audience and testing their long-term effects (Vlasceanu et al., 2024). With climate change continuing to accelerate, the need for robust, psychologically informed interventions is more urgent than ever. Future research should focus on refining these interventions and scaling them up to reach broader audiences.

References: 

Berkebile-Weinberg, M., Goldwert, D. et al. The differential impact of climate interventions along the political divide in 60 countries. Nature Communications 15, 3885 (2024). https://doi.org/10.1038/s41467-024-48112-8

Todorova, B. et al. Machine learning identifies key individual and nation-level factors predicting climate-relevant beliefs and behaviors. Preprint available at: https://doi.org/10.31219/osf.io/um69t (2024).

Vlasceanu, M., Doell, K. C.,  Bak-Coleman, J. B. et al. Addressing climate change with behavioral science: A global intervention tournament in 63 countries. Science Advances 10, eadj5778 (2024). https://doi.org/10.1126/sciadv.adj5778