Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioral changes that alter greenhouse gas emissions. Here, we link the CROADS climate model to a social model of behavioral change to examine how interactions between perceived risk and emissions behavior influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4–6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioral uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with the largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioral control with perceived social norms, and behaviors leading to sustained emissions reductions. Our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.