Persistence and unit root in CO2 emissions: evidence from disaggregated global and regional data

Understanding the properties of CO2 emissions is crucial in designing and implementing policies in the battle against climate change and global warming. One of the main characteristics of the CO2 emissions that needs to be examined is the degree of persistence of the emissions. This study examines the degree of persistence in aggregated and disaggregated CO2 emissions at the global and regional levels. The results from the subsampling confidence intervals show that the CO2 emissions, regardless of aggregation level, are highly persistent and non-stationary. Therefore, even a transitory shock will have a permanent effect on the emission of CO2. The same is true for CO2 emissions due to cement production and fuel consumption (gas, liquid, and solid). On the other hand, emissions from gas flaring appear to be stationary in most cases. In addition, the results show that emissions in the Middle East exhibit higher degrees of persistence compared to global emissions and emissions in Western Europe.