By Tony Nello, Senior Programme Coordinator – Urban, IUCN, Costa Rica, USA

As cities around the world grapple with rising temperatures and intensifying heatwaves, Nature-based Solutions (NbS) offer a powerful, cost-effective, and sustainable pathway to urban cooling. From tree-lined streets to rooftop gardens, NbS not only mitigate the urban heat island effect but also enhance biodiversity, public health, and social cohesion. Central to scaling these solutions is the active engagement of youth—who are increasingly leading the charge in transforming urban landscapes.

Scientific evidence underscores the cooling power of trees. Studies show that urban areas with dense tree cover can be up to 12–18°F (6.5–10°C) cooler than adjacent neighbourhoods with little vegetation (Hoffman et al., 2020). Trees cool cities through shading and evapotranspiration, reducing both surface and air temperatures. Yin et al. (2024) highlighted that canopy cooling benefits are most pronounced in densely built environments with high solar exposure, and that smaller trees in open public spaces can outperform artificial shade structures. In the contiguous United States, shade trees have been shown to lower near-surface air temperatures by an average of 3.06°C (Wang et al., 2018). However, their effectiveness can vary with species, canopy density, and climate conditions, especially during extreme heat events (Gao et al., 2024).

Youth play a pivotal role in protecting and enhancing these natural cooling assets. Across the globe, young people are organising tree-planting campaigns, managing urban gardens, and advocating for green infrastructure in city planning. Initiatives like Youth4Nature, Global Youth Biodiversity Network, and local programs in cities such as Detroit, Singapore, and Madrid demonstrate how youth-led action can reshape urban ecosystems.

Urban gardens, often spearheaded by youth groups, serve dual purposes: they cool the environment and improve food security. A systematic review found that community gardens enhance urban resilience, reduce food deserts, and foster environmental stewardship (Huq and Deacon, 2025). These gardens also promote healthier diets and reduce carbon footprints by encouraging local food production.

Moreover, youth are increasingly involved in urban tree stewardship—mapping tree cover, monitoring tree health, and participating in municipal greening programs. Their involvement ensures long-term care and community ownership of green spaces. In cities like Guangzhou and Baltimore, youth have contributed to NbS pilot projects that integrate ecological corridors and ventilation pathways into urban planning (World Bank, 2022).

To maximise impact, it is essential to:

• Integrate youth into urban planning processes, ensuring their voices shape NbS strategies.
• Invest in education and capacity-building, equipping young people with ecological knowledge and leadership skills.
• Support youth-led NbS projects through funding, mentorship, and innovation platforms.
• Promote inclusive governance, where youth collaborate with local authorities, civil society, and academia.

In conclusion, youth engagement is not a peripheral element—it is central to the success of NbS for urban cooling. By empowering young people to steward urban nature, we not only cool our cities but also cultivate a generation of climate leaders. Governments, civil society, and the private sector must recognise youth as strategic partners in the climate fight—and invest in nature as our most effective ally against the heat.

1. Gao, K., Feng, J., Santamouris, M., 2024. Are grand tree-planting initiatives meeting expectations in mitigating urban overheating during heatwaves? Sustain. Cities Soc. 113, 105671. https://doi.org/10.1016/j.scs.2024.105671
2. Hoffman, J.S., Shandas, V., Pendleton, N., 2020. The Effects of Historical Housing Policies on Resident Exposure to Intra-Urban Heat: A Study of 108 US Urban Areas. Climate 8, 12. https://doi.org/10.3390/cli8010012
3. Huq, F.F., Deacon, L., 2025. A systematic review of community gardens and their role in urban food security and resilience. Discov. Sustain. 6, 696. https://doi.org/10.1007/s43621-025-01628-5
4. Wang, C., Wang, Z.-H., Yang, J., 2018. Cooling Effect of Urban Trees on the Built Environment of Contiguous United States. Earths Future 6, 1066–1081. https://doi.org/10.1029/2018EF000891
5. World Bank, 2022. Piloting Nature-based Urban Cooling Solutions for Urban Regeneration and New Town Development in Guangzhou, China : Building a Cooler Guangzhou [WWW Document]. World Bank. URL https://documents.worldbank.org/en/publication/documents-reports/documentdetail/en/099014002092323118
6. Yin, Y., Li, S., Xing, X., Zhou, X., Kang, Y., Hu, Q., Li, Y., 2024. Cooling Benefits of Urban Tree Canopy: A Systematic Review. Sustainability 16, 4955. https://doi.org/10.3390/su16124955

Disclaimer: The views expressed in this piece are those of the author/s and do not necessarily reflect the views or policies of AIDMI.