Multidimensional welfare indices and the IPCC 6th Assessment Report scenarios

Abstract

The IPCC's 6th assessment report (AR6) has provided a wide range of variables and scenarios that meet climate targets of varying ambition. Many variables reported in the AR6 affect human welfare through climate change and mitigation, including but not limited to economic output, the natural environment, human health, and food and energy supply. In some of these dimensions, trade-offs exist between better performance in welfare-relevant dimensions and reaching more ambitious climate targets. Here, we apply recent advances in the theoretical multidimensional measurement of welfare, like the Human Development Index, to the AR6 database. The welfare metric is based on a welfare function approach, simple to apply, and intuitive. We apply a range of specifications of the welfare metric, aiming to derive robust rankings of climate policy targets that perform best in terms of the multidimensional welfare index. Across a large range of weights on welfare-relevant variables, we find that lower temperature is associated with higher welfare in 2100 unless there is a high weight on food supply.