The Green Infrastructure of Sandy Coastlines: A Nature-Based Solution for Mitigation of Climate Change Risks

Natural coastal landforms such as sand dunes and sandy beaches have been proposed as green infrastructure that can reduce climate change risks along coastlines. As such, they can offer a nature-based solution to rising sea levels, increased storminess and wave erosion associated with climate change. However, these proposed advantages are not always based on a sound understanding of coastal sediment system dynamics or tested against field evidence of coastal morphodynamic behavior. This study critically examines the basis of the claim for coastal landforms as green infrastructure, by considering how and in what ways these landforms provide resilience against ongoing climate change along sandy coasts, and proposes a theoretical framework for understanding this relationship. The analysis highlights that natural coastal landforms do not always have properties that provide resilience against future climate change. They can only be considered as offering nature-based solutions against climate change when their pre-existing morphodynamic behavior is fully understood. Thus, not all coastal landforms can be considered as ‘green infrastructure’ and the resilience offered by them against climate change forcing may vary from one place or context to another. This should be considered when using landforms such as sandy beaches and sand dunes as nature-based solutions for coastal management purposes. A 10-step framework is proposed, guiding coastal managers on how such green infrastructure can be used to mitigate climate change risks along coasts.