Addressing scale in nature-based solutions

Efforts to scale up NbS as a strategy to help reduce risk and adapt to climate change are the subject of growing debate. Despite increasing interest in mainstreaming NbS from both public and private actors, little is known about the mechanisms and conditions for scaling up NbS in practice or how upscaling can be brought about.

The literature on NbS often alludes to the need to implement such projects with a landscape approach, but the term is ill defined. The term recently has evolved to recognize the importance of landscapes for people’s quality of life, highlighting the need to adopt a more comprehensive approach that incorporates human well-being.

This shift raises important issues for the design, monitoring and governance of NbS. Where does a landscape begin or end? What is the right scale for landscape interventions? How should one assess performance in relation to the many and sometimes contradictory goals for biodiversity, societal benefits, mitigation and adaptation today and in the future? What metrics should be measured to understand whether NbS are adequate and effective?

Key messages

• Despite the growing interest in the use of nature-based solutions (NbS) to adapt to climate change, little is known about how to effectively scale up such measures to achieve wider benefits for society, biodiversity and the climate.
• NbS planning should thus seek to explicitly model cumulative and combined effects to inform the design of projects to address issues involving scales of time, landscapes, and jurisdictions involved.
• NbS designs should set quantitative targets and create monitoring systems to systematically measure outcomes and report on progress.
• NbS designs should implement “no regret” options – that is, they should devise strategies to maximize positive outcomes and minimize negative outcomes in the short and long terms and irrespective of climate change. This is particularly important in light of the longer time scales that NbS often entail, the time pressures to adapt fast enough to reduce risk, and the desire of politicians facing short elective cycles to respond to constituents’ needs.