Inequality Decomposition in the Distribution of Carbon Emission across Country Groups: Historical Trends and Future Implication

Abstract

The measurement of carbon inequality including Gini coefficient and historical cumulative Gini coefficient shows the current situation of carbon emissions, while the group decomposition of carbon inequality enables us to further unearth and understand the components and causes of the inequality. This paper takes use of two methods to calculate the contributions of between-groups and intra-group inequalities in order to decompose the overall inequality properly. In addition, all countries in the world are divided into Annex I Parties and Non-Annex I Parties which are the main sides in climate change negotiations. Then, considering the special situations of the least developed countries (LDCs), we make a comparative analysis by dividing the countries into LDCs, Annex I Parties and Non-Annex I Parties (without LDCs). The results prove that between-groups inequality is the main cause of overall inequality, taking the percentage of 60% to 80%, before 2009; total inequality reduces rapidly and between-groups and intra-group inequalities tend to reach the same level during 2009-2100. Furthermore, the declination of total inequality mainly results from the decrease of between-groups inequality; and intra-group inequality appears a mild upward tendency. Finally, between-groups inequality can be hidden to some extent if we don’t take historical cumulative emissions into consideration.