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The latest report of the Intergovernmental Panel on Climate Change showed that upcoming decades are likely to be accompanied with an increase in climate impacts in urban areas, thereby stressing the need for empowering cities to help them address the challenges ahead by closing the urban adaptation gap. The lock-in systems in which cities are often trapped create resistance to change and leads to missed opportunities to cocreate better futures. Putting nature at the center of urban adaptation agenda is a promising vision that nature-based solutions can help realize if city leaders are adequately supported in accessing the knowledge and resources they need to take action. Despite their proven potential, important barriers to the planning, implementation, and management of nature-based solutions (NbS) for urban climate adaptation persist and need to be urgently addressed. We highlight key barriers related to knowledge gaps and dissemination, policy incentives, and financial autonomy faced by city leaders trying to integrate NbS into policy and planning. In this perspective, we propose four levers of transformative adaptation which build on examples from Europe, the United States, Africa, and Latin America and which have proven successful in supporting cities adopting nature-based adaptation actions, including to 1) produce, assess and share knowledge; 2) adopt incentive-based policies and regulations; 3) facilitate access to multiple sources of funding; and 4) create reflexive monitoring mechanisms. If these steps are taken with the goal of addressing vulnerabilities on the ground, they can unleash the potential of NbS to engage on a path of transformative adaptation.
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Nature-based approaches to managing climate change impacts in cities
Managing and adapting to climate change in urban areas will become increasingly important as urban populations grow, especially because unique features of cities amplify climate change impacts. High impervious cover exacerbates impacts of climate warming through urban heat island effects and of heavy rainfall by magnifying runoff and flooding. Concentration of human settlements along rivers and coastal zones increases exposure of people and infrastructure to climate change hazards, often disproportionately affecting those who are least prepared. Nature-based strategies (NBS), which use living organisms, soils and sediments, and/or landscape features to reduce climate change hazards, hold promise as being more flexible, multi-functional and adaptable to an uncertain and non-stationary climate future than traditional approaches. Nevertheless, future research should address the effectiveness of NBS for reducing climate change impacts and whether they can be implemented at scales appropriate to climate change hazards and impacts. Further, there is a need for accurate and comprehensive cost–benefit analyses that consider disservices and co-benefits, relative to grey alternatives, and how costs and benefits are distributed across different communities. NBS are most likely to be effective and fair when they match the scale of the challenge, are implemented with input from diverse voices and are appropriate to specific social, cultural, ecological and technological contexts. This article is part of the theme issue ‘Climate change and ecosystems: threats, opportunities and solutions’.
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- PAR ID:
- 10157055
- Date Published:
- Journal Name:
- Philosophical Transactions of the Royal Society B: Biological Sciences
- Volume:
- 375
- Issue:
- 1794
- ISSN:
- 0962-8436
- Page Range / eLocation ID:
- 20190124
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1098/rstb.2019.0124
