Vulnerability Assessments in Support of the Climate Ready Estuaries Program: A Novel Approach Using Expert Judgment, Volume I: Results for the San Francisco Estuary Partnership (Final Report)
As part of the Climate Ready Estuaries (CRE) program, the Global Change Research Program (GCRP) in the National Center for Environmental Assessment, Office of Research and Development at the U.S. Environmental Protection Agency has prepared this draft report exploring a new methodology for climate change vulnerability assessments using San Francisco Bay’s salt marsh and mudflat ecosystems as a demonstration.
Estuarine ecosystems are highly vulnerable to climate-related changes in precipitation, hydrology, and sea level rise. As part of the CRE pilot program, GCRP collaborated with the San Francisco Estuary Partnership (SFEP) and the Massachusetts Bays Program (MBP) on ecological vulnerability assessments based on an expert elicitation exercise in a workshop setting. The results have been published as a series, with Volume I presenting the results for SFEP and Volume II presenting the results for MBP. For this project, an exercise was designed to elicit judgments from experts regarding climate change effects on two ecosystem processes for each pilot assessment: sediment retention and community interactions. The exercise is based on a novel application of expert elicitation (a process for obtaining the judgments of groups of experts to characterize their collective knowledge about ecological questions of interest). It was implemented during a two-day workshop using groups of seven expert participants for each ecosystem process examined.
During the workshop, the experts developed ecosystem models and used a coding scheme to characterize (1) relationships among key physical and ecological variables that regulate ecosystem processes, (2) relative sensitivities of these relationships under current and future climate change scenarios, (3) degree of confidence about these relationships, and (4) implications for management. This report shows how climate-sensitive pathways can be identified and linked to management options for adaptation to climate change. Adaptation refers to the ways in which management actions can be modified to reduce the negative impacts of climate change. The results of this study are designed to support SFEP’s adaptation planning efforts as well as those of other estuary managers.