To broaden our understanding of global climate change (GCC), this article presents results from an ongoing longitudinal research project that investigates public GCC risk perceptions in nine countries focusing on different perceptions important in policy formulation. A key goal of the study is to understand which nations express similar or different viewpoints with respect to explanatory factors such as threat perceptions, hazard experience, socio-demographics, knowledge of climate change, and other factors found in the environmental hazards literature. Despite many variances in GCC perceptions among the surveyed national populations, the analysis shows that some differences are marginal, while others allow the grouping of countries based on different perception factors. Survey results reveal a high degree of uncertainty with regards to climate change dimensions including risk, science, knowledge, and policy approaches to mitigate GCC.