Geographical spread of global emissions: Within-country inequalities are large and increasing

In spite of the extensive literature on greenhouse gas emission inequalities at the world-wide level, most of the evidence so far has been based on country-level data. However, the within-country dimension matters for both the implementation and the policy formation of climate policies. As a preliminary step towards a better understanding of within-country inequalities, this paper measures their extent for the two major greenhouse gases, CO₂ and CH₄, over the 1970–2008 period. Using Theil-index decompositions, we show that within-country inequalities account for the bulk of global inequality, and tend to increase over the sample period, in contrast with diminishing between-country inequalities. Including differences across sectors reveals that between-sector inequalities matter more than between-country inequalities, and between-sector inequalities become the dominant source of global inequality at the end of the sample period in the CO₂ case. Finally, estimated social tensions arising from the disconnection between emissions and future damages turn out to be increasing as soon as within-country disparities are taken into account. These orders of magnitude should be kept in mind while discussing the efficiency and fairness of alternative paths in combating global warming. - Highlights: • We estimate global spatial CO₂ and CH₄ inequality using grid data for 1970–2008. • Overall spatial emission inequality is constant for CO₂ and increasing for CH₄. • Within-country inequality is rising and constitutes the main bulk of overall inequality. • An important part of within country inequality is due to differences among sectors. • The gap between emitters and victims is rising within countries.