Policy diffusion of emission regulations for on-road vehicles: Causes and benefits for air quality

My dissertation covers a broad range of topics from atmospheric chemistry to international relations and the politics of East Asia, combining them into an overall examination of the diffusion mechanism of environmental policies. There are three parts to my dissertation, each analyzing different dimensions of policy diffusion of air pollution regulations.;The first part examines the impacts of policy diffusion on air quality. Chemical transport models are used to analyze concentrations of pollutants in the atmosphere. First, an analysis of present and possible future scenarios of China's aerosol emissions finds that the reduction of China's aerosol emissions will not only improve air quality, but will save many lives, primarily in Northeast Asia. However, this also leads to the loss of global net negative radiative forcing. Second, looking more closely at China's road transport sector, an analysis of the impact of China's vehicle emissions on regional air quality finds significant benefits within China and more broadly within East Asia by the effective regulation of current emission standards.;The second part analyzes why vehicle emission standards have diffused to 67 countries. Using econometric analysis of standard adoption over the past 20 years, I argue that the global diffusion results from countries' efforts to stay competitive in the international market. Due to the pressure from importing countries and from economic competitors that have adopted standards, even developing countries adopt stringent emission standards to stay in the market. I further contend that a country's automobile export trade value is positively influenced by its adoption of automobile emission standards. This finding counters expectations that globalization will lead to a race to the bottom.;The third part of my dissertation is a case study of the policy diffusion mechanism within China at both the national and the local levels. Having interviewed 78 people in Asia, I closely trace the policymaking processes for the decisions to adopt two standards essential for regulating emissions from automobiles: emission standards and fuel quality standards. I argue that open policymaking process enhances policy diffusion in China.