Assessment of Environmental Kuznets Curves and Socioeconomic Drivers in IPCC’s SRES Scenarios

Abstract

The Special Report on Emissions Scenarios (SRES) produced families of 21st century greenhouse gas (GHG) emissions trajectories that aim to be consistent with current knowledge and span a wide range of plausible futures. This study performs a standard econometric analysis on the simulation model outputs from six SRES scenarios to assess the extent to which the projected CO2 and NOx emissions reflect Environmental Kuznets Curve (EKC) behavior. Consistent with the empirical literature, which offers little consensus on the predictive value of the EKC hypothesis, our analysis finds that some SRES scenarios exhibit EKC behavior while others do not. Those showing EKC behavior have turning points—per captia income levels separating rising and falling emissions—similar to those found in empirical studies. Overall, this analysis supports the SRES scenarios as generally consistent with and spanning a wide range of different interpretations found in the EKC literature.