Decomposition and decoupling of CO₂ emissions in Türkiye: Evidence from an extended Kaya-LMDI framework (1990–2024)

Abstract

This study investigates the relationship between economic growth and  emissions in Türkiye from 1990 to 2024, using the extended Kaya identity, a framework that combines the Tapio decoupling approach with the Logarithmic Mean Divisia Index (LMDI) decomposition method. Changes in  emissions are decomposed into population, income per capita, energy intensity, fuel mix, and fuel-based carbon intensity, and both total and component-based decoupling elasticities are calculated. The results show that Türkiye experienced weak decoupling over the long term, indicating that economic growth has not been fully decoupled from increases in emissions. This pattern is mainly associated with improvements in energy intensity and fuel-based carbon intensity, while income per capita growth and changes in the fuel mix remain the primary drivers of emissions increases. The sub-period analysis indicates that the growth-emissions relationship is not stable over time. An expansive coupling pattern is observed in 1990-2001, whereas a relatively stronger decoupling is observed in 2009-2018. Counterfactual scenario analysis further shows that improvements in energy intensity play a crucial role in limiting the growth of emissions. Overall, the findings indicate that Türkiye’s decoupling process is largely driven by efficiency improvements rather than structural changes in the energy system, and that structural transformation remains limited.

Keywords

• CO2 emissions
• Kaya identity
• LMDI
• Tapio decoupling

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