EbA valuation is the process of describing, measuring and analysing how the benefits, costs and impacts arising from the implementation of ecosystem-based approaches to adaptation are generated, received and perceived. While the term valuation is variously understood, there is general consensus that it should be taken to refer to a process of expressing and communicating information about how much something is worth. There are three basic elements of EbA value: benefits, costs and impacts.
Benefits are the advantages or positive effects of EbA measures; costs are the resources required to deliver EbA measures, and the disadvantages or negative effects caused by them; and impacts are the effects or changes in situations or circumstances that arise as a consequence of EbA measures having been undertaken. Basically, EbA benefits and costs interact to result in particular impacts. This sourcebook addresses the topic of EbA valuation. It offers a resource to guide the design, delivery and use of EbA valuation studies to inform and influence decision-making.