LAUSR

Despite the heated debate over the relationship between economic development and carbon dioxide (CO 2 ) emissions, few studies have focused on the impact of spatial relationships between neighboring countries on CO 2 emissions. Adopting the World Bank’s classification of income levels, this paper classifies 177 countries into four groups and then analyzes the spatial-temporal variations in CO 2 emissions. Based on that analysis, the core task of our study is to estimate a carbon Kuznets curve (CKC) from two methods of traditional statistics and spatial econometrics. The main findings indicate that global CO 2 emissions have significant spatial clustering characteristics, and the clustering types are closely linked to geographic location and income level. In addition, the existence of standard CKC and spatial CKC were confirmed. Countries with different income levels have different CO 2 emission stages, and a country’s CO 2 emissions are affected both directly by its own economy and indirectly by the economies of its neighbors. In this context, the mitigation and adaptation strategies for CO 2 reduction are proposed as follows. (1) Neighboring countries must develop regional cooperative initiatives to reduce CO 2 emissions. (2) Clarifying the emission stage of a country is an important basis for policymakers to formulate emission reduction strategies. (3) The economic development and CO 2 emissions of neighboring countries are also important factors in formulating emission reduction plans.