Layout 1

This policy brief from the MEDIATION project evaluates the use of Cost-Effectiveness Analysis (CEA) as a decision support tool for climate change adaptation. While CEA is a primary tool for mitigation, the document highlights that its application to adaptation is more challenging due to the lack of a single common metric and the critical need to account for uncertainty.

• Cost-Effectiveness Analysis (CEA) is a relative measure used to rank options by assessing the cost per unit of benefit delivered, identifying the most cost-effective choices. It can be used to create marginal abatement cost (MAC) curves to identify the least-cost path to achieve pre-defined policy targets.
• Applying CEA to adaptation is significantly more demanding than applying it to mitigation. Mitigation relies on a single global metric (tonnes of GHG emissions), whereas adaptation responds to diverse local, regional, or national impacts across different sectors, meaning there is no single common metric for cross-sectoral analysis.
• A primary strength of CEA is its ability to avoid the monetary valuation of economic benefits, making it useful for non-market sectors like ecosystems where valuation is contentious. However, it often focuses on technical options and may omit capacity building, non-technical 'soft' measures, and the inter-linkages found in portfolios of options.
• Most CEA applications fail to consider uncertainty, often relying on single cost curves or central estimates for future climate change, which the MEDIATION project warns can provide misleading results. To address this, the document recommends using multiple cost curve analysis and sampling across various socio-economic and climate model projections.
• CEA is most effective for near-term assessments and identifying 'low and no regret' options, particularly in areas with a clear headline indicator and low climate uncertainty. For long-term use, it should be integrated into an iterative adaptive management plan rather than used as a standalone tool.
• The MEDIATION project conducted a case study on biodiversity in Finland focusing on grassland butterflies. The study found that while cattle grazing is the most efficient measure for butterflies, buffer zones are the most cost-effective Agri-Environmental Scheme (AES) measure when costs are considered.

APA

Stockholm Environment Institute (n.d.). Layout 1. https://www.sei.org/mediamanager/documents/Publications/sei-mediation-briefing2-cost-effective-analysis.pdf

Chicago

Stockholm Environment Institute. Layout 1. n.d. https://www.sei.org/mediamanager/documents/Publications/sei-mediation-briefing2-cost-effective-analysis.pdf.

Wikipedia

{{cite report |author=Stockholm Environment Institute |title=Layout 1 |url=https://www.sei.org/mediamanager/documents/Publications/sei-mediation-briefing2-cost-effective-analysis.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stockholmenvironmentinstitutendlayout, author = {{Stockholm Environment Institute}}, title = {{Layout 1}}, institution = {Stockholm Environment Institute}, url = {https://www.sei.org/mediamanager/documents/Publications/sei-mediation-briefing2-cost-effective-analysis.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }