Many studies have been published to evaluate the consequences of different post-2012 emission allocation regimes on regional mitigation costs. This paper goes one step further and evaluates not only mitigation costs, but also adaptation costs and climate change damages. This analysis shows that including costs other than mitigation costs does give a very different perspective on regional costs. In all allocation regimes, emission trading can already lead to such a transfer of funds from developed to developing countries that it compensates their adaptation costs and climate change damages, at least for the next few decades. Finally, differences between the regimes are considerable in the short to medium term, but they all move in a similar direction, in the long term.
This paper evaluates mitigation costs, adaptation costs and climate change damages for three post-2012 emission allocation regimes (Contraction & Convergence, Multistage and Common but differentiated convergence) and two climate targets (2 °C and 3 °C above the pre-industrial level). This explorative analysis shows that including these other cost categories could lead to different perspectives on the outcomes of allocation regimes. Up to 2050, the poorest regions have negative mitigation costs under all allocation regimes considered, as they benefit from emission trading. However, these regions also suffer from the most severe climate impacts. As such, the financial flows due to emission trading from developed to developing countries created under these allocation regimes could also be interpreted as compensation of climate change damages and adaptation costs. In the longer run, the sum of climate change damages, adaptation costs and mitigation costs are the highest in the poorest regions of Sub-Saharan Africa and South Asia, for both climate targets and practically all emission allocation regimes.