Population change and environmental degradation have become two of the most pressing issues for sustainable development in the contemporary world, while the effect of population aging on pro-environmental behavior remains controversial. In this paper, we examine the effects of individual and population aging on pro-environmental behavior through multilevel analyses of cross-national data from 31 countries. Hierarchical linear models with random intercepts are employed to analyze the data. The findings reveal a positive relationship between aging and pro-environmental behavior. At the individual level, older people are more likely to participate in environmental behavior (b = 0.052, p < 0.001), and at the national level, living in a country with a greater share of older persons encourages individuals to behave sustainably (b = 0.023, p < 0.01). We also found that the elderly are more environmentally active in an aging society. The findings imply that the longevity of human beings may offer opportunities for the improvement of the natural environment.

Climate change governance has attracted increasing academic interest. However, holistic reviews on the dynamic complexity and stability of climate change governance have received little attention. This study addresses this research gap by conducting a structurally comparative analysis between China and the United States based on the “polity–policy–politics” framework. Three analytical facets are identified for each dimension of the framework, including institutional settings, the nature of policy mechanisms used in climate change practices, and the degree of multi-actors’ involvement under two governance scenarios. Results show that climate change governance in the two countries differs substantially. The process of climate governance in China is driven by strong leadership at the national level alongside policy continuity, whereas well-functioning market mechanisms and robust regulatory systems are still lacking. A more meaningful involvement of social forces is also critically needed when addressing increasingly complex and uncertain climate change. By contrast, the US federal climate policies are considered inadequate compared with sub-national actions and persistent efforts of non-state actors, to which the success of climate practices is largely attributed. This study systematically uncovers the divergence of climate mitigation under different political–institutional contexts, and evaluates the effectiveness of governance arrangement in the two countries, which helps policymakers to understand the potential of improving the performance of climate change governance.