ERG’s Dr. Julie Blue served as a technical contributor for the recently released Fourth National Climate Assessment (NCA4). The U.S. Global Change Research Program charged EPA with developing NCA4’s chapter on the built environment. Based on extensive reviews of the scientific literature, Dr. Blue supported EPA in developing the chapter’s key messages. Dr. Blue’s research included leading development of the traceable accounts sections of the chapter, which provide evidence for the key messages from the scientific literature, as well as research on five cities representing archetypes of desert, mountain, rust belt, coastal, and agriculturally influenced cities. As a follow-up to this work, Dr. Blue—a hydrologist by training and ERG’s principal climate scientist—will present information from NCA4 at the upcoming National Council for Science and the Environment’s 2019 annual conference and elsewhere.