According to estimates published in Poverty and Shared Prosperity 2016, the Gini Global Inequality Index rose from 0.67 in 2008 to 0.62 in 2013. This marked a reversal of the trend, as global inequality began from the 19th century to 1988, and then found itself on a plateau for two decades. Similarly, results in climate finance, technology transfer and capacity building appear to be cascading (see Figures 3-6). While the encoding of requests for support is clearly visible, no cascade of pledges of support can be observed. As in the case of adaptation, this article cannot dictate what an “ideal” cascade would look like in terms of consistency with the subtle differentiation of the Paris Agreement. On the one hand, the Paris Agreement contains no information justifying such requirements. On the other hand, it is outside the scope of this article to give an expectation based on the extent to which requests for assistance and NDC contributions reflect either existing support flows or the needs of countries (cf.B. Betzold and Weiler (2017) and Kl-ck et al. (2018) for debates on the allocation of climate finance). Below we describe encoding both for requests for assistance and later for providing support. Between 2008 and 2013, global inequalities between countries decreased for the first time since the industrial revolution. This is mainly due to the steady increase in incomes in populated developing countries such as China and India. At present, two-thirds of global inequality is still due to differences in average incomes between countries and not to inequalities within countries, which means that the case where a person is born is a determining factor in his or her future prospects and that eliminating inequalities between countries should be a priority.
However, the data also indicate that inequalities within countries are worsening, particularly in high- and middle-income countries. Our data indicate a slight decrease in global inequality for the first time since the beginning of the 19th century. This is a positive trend, but there is no guarantee that it will continue. Policymakers should not simply create the conditions for inclusive economic growth. In other words, responsibility for reducing CO2 emissions must be borne by the highest-income countries and by the most privileged social groups in some emerging and developing countries. Achieving this goal requires a drastic contraction of consumption habits. The surest way to achieve the COP21 goals is to combat inequality and strengthen social ties, especially if we are to achieve the most ambitious goal of capping the average increase in global temperature at just 1.5 degrees Celsius.