The process of peak CO2 emissions in developed economies: A perspective of industrialization and urbanization

The experiences of peak carbon emissions in developed economies can provide a significant reference for other economies. In terms of peak carbon intensity, per capita carbon emissions and carbon emissions, the peak process in developed economies is divided into three stages. This study analyzes gross domestic product (GDP), per capita GDP, industrialization rate, urbanization rate, and other indicators in each stage. The impacts of urbanization and industrialization on carbon emissions are examined by using a threshold regression model. The results indicate that urbanization and income level have a significant double-threshold effect on carbon emissions. From the perspective of urbanization, there is no significant correlation between carbon emissions and urbanization in the low-urbanization stage. However, urbanization has a negative effect on carbon emissions in the mid-urbanization stage. Then, this inhibitory effect becomes a promotional effect when the urbanization level crosses the second threshold. From the perspective of income level, industrialization contributes to the growth of carbon emissions. The promotional effect of industrialization on carbon emissions gradually increases in the low and intermediate income levels. However, this promotional effect begins to weaken in the high income level. Our study not only extends the existing literature about peak carbon emissions, but also merits particular attention for policy makers in less developed economies.