Global mapping of urban nature-based solutions for climate change adaptation

Many cities around the world are experimenting with nature-based solutions (NbS) to address the interconnected climate-, biodiversity- and society-related challenges they are facing (referred to as the climate-biodiversity-society, or CBS, nexus), by restoring, protecting and more sustainably managing urban ecosystems. Although the application of urban NbS is flourishing, there is little synthesized evidence clarifying the contribution of NbS in addressing the intertwined CBS challenges and their capacity to encourage transformational change in urban systems worldwide. We map and analyse NbS approaches specifically for climate change adaptation across 216 urban interventions and 130 cities worldwide. Results suggest that current NbS practices are limited in how they may comprehensively address CBS challenges, particularly by accounting for multidimensional forms of climate vulnerability, social justice, the potential for collaboration between public and private sectors and diverse cobenefits. Data suggest that knowledge and practice are biased towards the Global North, under-representing key CBS challenges in the Global South, particularly in terms of climate hazards and urban ecosystems involved. Our results also point out that further research and practice are required to leverage the transformative potential of urban NbS. We provide recommendations for each of these areas to advance the practice of NbS for transformative urban adaptation within the CBS nexus. Nature-based solutions for climate adaptation are not comprehensively addressing the climate-biodiversity-society nexus, limiting their capacity to promote urban transformation. However, notable transformative examples of urban nature-based solutions do exist, especially in the Global South.