Source: Asia Development Bank
Despite their broad potential, nature-based solutions are often overlooked in city cooling strategies. Key barriers include a lack of supportive policies, financial constraints, and limited institutional capacity.
Addressing these challenges requires a multi-pronged approach that maximizes NbS benefits and integrates them into broader heat action plans. This must involve reducing waste heat (e.g., from transport and buildings), addressing cooling needs efficiently, and ensuring equitable access to thermal comfort. Key considerations for incorporating NbS into urban cooling strategies include:
- Integrated planning: A systems approach ensures NbS are complemented by other solutions to maximize their benefits.
- Equity: Cooling solutions must be distributed fairly, with heat equity embedded in planning to prevent future injustices.
- Community participation: Involve women and vulnerable groups in designing and implementing cooling programs that deliver real benefits.
- Local solutions: NbS should be tailored to local climates, needs, and traditional approaches (e.g., architecture).
Studies suggest that 30% of cities should be dedicated to green or blue spaces. Achieving this requires enabling strategies like raising awareness, building institutional capacity, and securing financing. It also involves assessing current natural assets and identifying vulnerable communities. Partnerships with the private sector can help provide technical expertise and funding. In developing countries, protecting existing green spaces from development is the most effective way to maintain cooling.
Creating a cooling-friendly urban form requires time and sustained effort. In the near term, practical, no-regret actions to build resilience to heat stress through NbS include:
- Establishing champions and authorities to protect and enhance green and blue spaces
- Conducting baseline assessments of green and blue spaces and identifying vulnerable communities
- Investing in green and blue infrastructure, especially in public areas
Tree planting is perhaps the simplest and most effective action to reduce urban heat—provided the right trees are planted in the right places as part of a coordinated city-wide greening effort. Steps taken today will help future generations benefit from NbS for cooling.