Nature Based Solutions (NbS) are seen as a promising venue for coastal adaptation to climate change. Combining natural dynamics with technical solutions, NbS can be driven by unpredictable natural dynamics, unanticipated surprises, and changing external conditions. And as such, they involve fundamentally different uncertainties.
There are three main kinds of uncertainty: lack of knowledge, unpredictability, which refer to a deficit of knowledge about a system, and ambiguity. Ambiguity is considered an uncertainty of a different kind, as it does not attend to how much, or how well, actors know a system, but to the different ways of knowing about it and of framing concerning issues.
These uncertainties are interrelated, influencing each other. So, the impact of a particular uncertainty may be created or enlarged through the cascading effects of other uncertainties. However, little is still known about the effects that these uncertainties concerning NbS function and effectiveness, considering both the positive and negative impacts that NbS may have in our society.