Tracking the inequalities of global per capita carbon emissions from perspectives of technological and economic gaps.

Facing up to global carbon inequality is an important prerequisite for the fair allocation of carbon emission reduction tasks. This study proposed a new index to measure carbon inequality and then constructed a data envelopment analysis-based decomposition framework to focus on the impacts of the economic development gap and the technology gap on carbon inequality. Based on a dataset of 83 countries (or regions) during 1990-2017, we discuss global carbon inequality and its driving factors and further reveal the discrepancies among different income groups and countries. The main findings indicate that: (1) global carbon emissions showed significant inequality in all years and have an overall decreasing tendency. (2) High-income countries tended to display larger carbon inequality and witnessed great variation in different years. Upper middle-income and lower middle-income countries had relatively low carbon inequality and only experienced very minor variation. (3) Economic development disparity was the foremost factor leading to carbon inequality enlargement in most countries, especially the countries with higher income. The production technology gap played an important role in narrowing carbon inequality, whereas the energy-saving technology gap only exerted a minor effect on carbon inequality.