Study #25

Figure: Comparison of the NbS review of reviews with regional expert assessments resulting in four insights suggesting key pathways forward for advancing the science and practice of urban NbS.

Nature-based solutions insights - A Global Roadmap for Greener Cities

In 2025, an international team of scientists led by Timon McPhearson conducted a global study examining how cities can better use nature-based solutions (NbS) like urban forests, wetlands, and green roofs to tackle climate change and urban challenges. Published in Proceedings of the National Academy of Sciences, the research synthesized evidence from 61 scientific review articles and assessed knowledge from seven global regions.

Their findings are clear: cities are increasingly turning to nature for solutions, but the path is not simple. The researchers identified eight major challenges slowing progress, including governance gaps, lack of ecological knowledge, limited health evidence, and insufficient attention to equity.

Most knowledge about nature-based solutions comes from the Global North, leaving major gaps in regions where urban growth and climate risks are rising fastest. The authors suggest four key pathways to scale up nature in all cities: stronger research and innovation, global knowledge-sharing alliances, integrated systems thinking, and increased financing and political commitment.

When cities design with nature, they can address climate, biodiversity, and social challenges at once. But success depends on local knowledge, inclusive governance, and global collaboration.

McPhearson, T., Frantzeskaki, N., Ossola, A., Diep, L., Anderson, P. M. L., Blatch, T., … Zhou, W. (2025). Global synthesis and regional insights for mainstreaming urban nature-based solutions. Proceedings of the National Academy of Sciences, 122(29), e2315910121.
https://doi.org/10.1073/pnas.2315910121