This article extends recent work on the public arenas approach to social problems (Hilgartner and Bosk 1988) by examining changes in audience receptiveness to claims-making activities. Scientists’ claims about global warming failed to attract much public attention until the extraordinary heat and drought of the “summer of '88” created a social scare. That is, environmental claims are most likely to be honored—and accelerate demands in the political arena—when they piggyback on dramatic real-world events. The dynamics of this social problem over time reveal that both demand attenuation and issue redirection processes have diminished global warming's standing as a “celebrity” social problem. Social scares hold potential importance for prospective social problems that revolve around new technologies.