Today, 97% to 99.9% of climate scientists agree that climate change is happening and that human activity is the primary cause. Over the past decade, researchers have begun to study the effects of communicating this overwhelming consensus – with promising results. So far, however, such studies have primarily been conducted in the United States.

This new study takes an extensive and detailed look at the effects of communicating scientific consensus beyond the United States. ‘We observed that previous findings from the United States hold true in other parts of the world as well,’ says co-lead author Bojana Većkalov from the University of Amsterdam.  

People estimated consensus much lower than it really is

The international research team of 46 collaborators showed different scientific consensus messages on the reality of climate change to more than 10,500 people and subsequently asked them about their opinions on climate change. Across all 27 countries, people responded similarly to the scientific consensus on the existence and causes of climate change.

Environmental psychologist and co-lead author Sandra Geiger from the University of Vienna explains: ‘Prior to reading about the consensus among climate scientists, people estimated this consensus to be much lower than it really is. In response to reading about it, they adjusted their own perceptions, believed more in climate change, and worried more about it.’

Additional crisis consensus has no added value

88% of climate scientists additionally agree that climate change constitutes a crisis. How do people react when they learn about this additional crisis consensus? Interestingly, this piece of information provided no added value. Većkalov explains: ‘We believe that the gap between the actual and perceived consensus could have played a role. When it came to consensus on the existence and causes of climate change, respondents thought the scientific consensus was lower than it actually was, adjusted their estimate, and revised their beliefs. In the case of the crisis consensus, the respondents’ estimate was substantially closer to the actual consensus, and this gap was likely not big enough to alter beliefs about climate change.’

The study also found that both consensus messages are more effective for audiences with lower message familiarity and higher misperceptions, including those with lower trust in climate scientists and right-leaning ideologies.

Continue emphasizing the consensus among climate scientists

These new findings show that it is important to continue emphasizing the consensus among climate scientists – be it in the media or in our everyday lives when people have conversations about climate change and its impacts. ‘Especially in the face of increasing politicization of science and misinformation about climate change, cultivating universal awareness of the scientific consensus will help protect public understanding of the issue’, adds senior author Sander van der Linden from the University of Cambridge.

Besides Bojana Većkalov, František Bartoš, Bastiaan Rutjens, Frenk van Harreveld, Berkan Akın, and Alaa Aldoh from the University of Amsterdam were also involved in this study. What is particularly unique about this work is the involvement of students and early-career researchers from the Junior Researcher Programme (JRP) and the Global Behavioral Science (GLOBES) program at Columbia University.

Publication details

Većkalov, B., Geiger, S. J., Bartoš, F., White, M. P., Rutjens, B. T., van Harreveld, F., … Ruggeri, K. & van der Linden, S. (2024). 'A 27-country test of communicating the scientific consensus on climate change.' Nature Human Behaviour. https://www.nature.com/articles/s41562-024-01928-2  (A full list of authors is available in the study article).