Return exactly one rewritten English science news headline for the original title below. Maximum 12 words. Output plain text only. Do not use HTML, Markdown, quotes, labels, explanations, bullets, numbering, or multiple options. Original title: Social norms can accelerate or undermine climate action, new model finds

A new mathematical model suggests that social norms may be just as important as economics in determining how the world responds to climate change. The research shows that efforts to reduce emissions in one region can unintentionally influence climate action elsewhere, with consequences that could either strengthen or weaken global progress.

The model divides the world into five culturally and economically distinct regions and simulates how social norms, perceived climate risks and economic pressures interact to shape climate action.

“Climate models often assume people are rational economic actors who always act in their own best interest,” said Dr. Chris Bauch, professor of applied mathematics at the University of Waterloo. “Our model recognizes that people are also influenced by social norms, whether that’s eating more beef or choosing reusable water bottles, and those behaviours can significantly affect climate change mitigation.”

The model draws on existing data describing cultural values and behaviour across Asia, Latin America, the Middle East and Africa, OECD countries and the Reforming Economies of Eastern Europe and the former Soviet Union. It models how social and economic factors influence mitigation efforts, which in turn affect global warming.

The researchers found that strategies that encourage climate action in one region may have the opposite effect elsewhere.

“We found that greater discussion about climate change often increases support for mitigation, but in some regions, it can also fuel anti-mitigation sentiment,” said lead author Amrita Punnavajhala, who recently completed her PhD in applied mathematics at Waterloo. “The best approach depends on each region’s unique social and economic circumstances rather than a one-size-fits-all solution.”

The model also reveals how regional actions can create unexpected ripple effects.

“If Asia increases its mitigation efforts, global warming slows slightly, which can reduce the perceived urgency in OECD countries such as Canada and the United States,” Bauch said. “That could weaken social pressure for climate action and create harmful long-term consequences.”

“There are constant feedback loops between climate change and human behaviour,” said Dr. Madhur Anand, professor of environmental science at the University of Guelph and adjunct professor in Waterloo’s Department of Applied Mathematics. “Understanding those relationships will be essential to reducing emissions and building a more sustainable future.”

The study, Implications of regional variations in climate change vulnerability and mitigation behaviour for social-climate dynamics, appears in Nature Communications.