A new mathematical model suggests that social norms may be as influential as economic forces in determining how societies respond to climate change. The research shows that efforts to reduce greenhouse gas emissions in one part of the world can unexpectedly affect climate action elsewhere. These ripple effects may either strengthen global mitigation efforts or weaken progress, highlighting the complex relationship between human behaviour and climate change.

Developed by researchers at the University of Waterloo and the University of Guelph, the model divides the world into five culturally and economically distinct regions. It examines Asia, Latin America, the Middle East and Africa, OECD countries, and the Reforming Economies of Eastern Europe and the former Soviet Union. By combining existing data on cultural values and behaviour, the model simulates how social norms, perceived climate risks and economic pressures interact to influence mitigation efforts and, ultimately, global warming.

Traditional climate models often treat people primarily as rational economic decision-makers who consistently act in their own financial interests. The new model takes a broader approach by recognising the powerful influence of social expectations and everyday behaviours. Dr Chris Bauch, professor of applied mathematics at the University of Waterloo, explained that social norms can shape choices ranging from eating more beef to using reusable water bottles. When such behaviours become widespread, they can have a significant impact on efforts to reduce emissions and limit climate change.

The researchers found that strategies designed to encourage climate action do not necessarily produce the same results in every region. Greater public discussion about climate change often increases support for mitigation, but it can also intensify opposition in certain social and economic environments. Lead author Amrita Punnavajhala, who recently completed her PhD in applied mathematics at Waterloo, said the findings demonstrate why climate policies must account for regional differences. Rather than relying on a universal solution, effective strategies may need to reflect each region’s distinctive cultural, social and economic circumstances.

The model also reveals how stronger climate action in one region can create unintended consequences elsewhere. For example, if Asia increases its mitigation efforts, the resulting slowdown in global warming could reduce the sense of urgency in OECD countries such as Canada and the United States. According to Bauch, a lower perception of immediate climate risk could weaken social pressure for further action in those countries. Over time, this response could undermine some of the benefits created by stronger mitigation efforts in other parts of the world.

The findings highlight the constant feedback loops connecting climate change, social norms and human behaviour. Dr Madhur Anand, professor of environmental science at the University of Guelph and an adjunct professor in Waterloo’s Department of Applied Mathematics, said understanding these relationships will be essential for reducing emissions and creating a more sustainable future. The researchers suggest that climate strategies should consider not only economic incentives and environmental risks, but also how social attitudes spread within and between regions. Recognising these complex interactions could help policymakers develop more effective and locally appropriate approaches to global climate action.

More information: Amrita Punnavajhala et al, Implications of regional variations in climate change vulnerability and mitigation behaviour for social-climate dynamics, Nature Communications. DOI: 10.1038/s41467-026-73874-8

Journal information: Nature Communications Provided by University of Waterloo