Decoupling transport-related CO2 emissions from economic growth: Empirical analysis (2000–2023)
Abstract
This study investigates the dynamic relationship between economic expansion measured by Gross Domestic Product at Purchasing Power Parity (GDP at PPP) and transport-related carbon dioxide (CO2) emissions in Hungary over the period 2000–2023. Using the Julia 1.10 programming language for high-performance statistical processing, the research employs a three-tier methodology comprising Augmented Dickey-Fuller (ADF) unit root testing, the Tapio elasticity framework, and Pearson correlation analysis of growth rates. The empirical results reveal that although absolute levels of GDP and emissions are non-stationary, their yearly growth rates are statistically independent (r = 0.17, p > 0.05), suggesting a significant break in the traditional carbon-growth nexus. The Tapio analysis identifies a prolonged “Strong Decoupling” phase from 2008 to 2013, followed by a return to efficiency-driven decoupling in 2023. These findings suggest that structural improvements and technological advancements have increasingly superseded economic volume as the primary drivers of transport emissions.
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