Re-examining Emissions. Is Assessing Convergence Meaningless?

This paper sets out to re-examine CO2 emissions for 22 OECD countries over the period 1870–2006. The aim is to help explain mixed evidence regarding convergence in per capita emissions among countries. The paper revolves around two potential sources of inconclusive findings regarding CO2 emissions convergence: firstly, neglecting the step prior to convergence analysis could mislead researchers as the stationary nature of series negates the possibility of convergence; secondly, the nonlinear dynamics of CO2 have not been considered to date. The empirical evidence provided by our methodological strategy suggests that the original per capita CO2 emissions are non-stationary from 1950 onwards, allowing for further convergence study. By the novelty appeal of using nonlinear methods, we conclude that there is strong evidence of divergence among these 22 OECD countries.