Challenges and Opportunities for Incorporating Climate Change’s Impacts on Ocean Systems into the Social Cost of Greenhouse Gases

The social cost of greenhouse gases (SC-GHG) is an estimate of the economic cost to society of an incremental metric ton of emissions of a given greenhouse gas. Recent advances in SC-GHG estimates represent a major step forward towards a comprehensive accounting of the impacts of greenhouse gases, yet they still omit important impacts of climate change such as its effects on ocean ecosystems and fisheries. As a step towards incorporating ocean system impacts into SC-GHG estimates, researchers at Resources for the Future (RFF) and their colleagues convened a group of 40 scientists and policymakers for a series of three strategic workshops. The first workshop served to level-set participants on state-of-the-art SC-GHG modeling, using the RFF-Berkeley Greenhouse Gas Impact Value Estimator (GIVE) model as an example. The second and third workshops focused on two topics identified as priority areas: coral reefs and fisheries. Key topics of discussion included: i) available statistical techniques well suited to the complexities of ocean ecosystems and economies, ii) the importance of the compounding effects of multiple stressors such as temperature increases, extreme events, and ocean acidification on coral reefs and how to capture them in projections of future climate scenarios, and iii) approaches to modeling recreational and commercial fisheries while accounting for economic dynamics such as substitution effects and hedonic adaptation, as well as resource-driven geopolitics. This report documents the dialogue from the workshops, serving as reference material for continuing collaboration to incorporate ocean impacts into more comprehensive SC-GHG estimates.