Climate change versus the water–energy–food nexus: the oldness or newness of the scientific issues as a factor in the deficit model and the hierarchy of response model

Environmental issues need public support to be solved. But the theoretical model that supports providing the public scientific information to enhance their support for scientific issues, the deficit model, is confirmed in some studies but disapproved in others. Hypothesizing that the difference lies partially in the topic of issues used in those studies, this study tests the deficit model (and the expanded linkage from knowledge to attitude to behavioral intention in the hierarchy of response model) with the complex issue of climate change (N = 379), which is entangled with political and ideological confounders, and the new water–energy–food nexus (N = 524), which is involved with few confounders. The survey on climate change, a hotly debated issue deeply entangled with many social, economic, and political factors, revealed a substantial positive correlation between attitude and behavioral intention and no correlation between knowledge and attitude or behavioral intention, producing no evidence to support the deficit model and partial evidence to support the hierarchy of response model. The partial correlation analysis of this data, controlling age, gender, and ideology, also identified a negative relationship between knowledge and behavioral intention, further calling researchers’ attention to the influence of the complexness of the scientific event on public information processing. The survey on the WEF nexus, a new scientific approach that systematically governs water, energy, and food as a nexus, showed positive correlations of knowledge with attitude and of attitude with behavioral intention, confirming the deficit model as well as the traditional response hierarchy model. The study suggests that when confounding variables do not intervene, the deficit model and the traditional response model hold to guide science communication projects and garner public support for science and the environment.