Decoupling Effect and Influencing Factors of Transportation Carbon Emissions in Hainan Province

Hainan is the first province in China to announce a comprehensive ban on the sale of fuel vehicles by 2030, aimed at promoting low-carbon transportation development. This paper uses the top-down method of the IPCC to estimate the transportation carbon emissions in Hainan Province from 2006 to 2020. At the same time, considering the impact of structural adjustments, technological advancements, and urbanization developments, the traditional LMDI model was improved and combined with the Tapio model to analyze the decoupling status of transportation carbon emissions and economic development in Hainan Province, as well as the contribution values and rates of various influencing factors. The study reveals: 1) The total transportation carbon emissions increased by 208.68 ten thousand tons, showing a trend of rapid initial rise followed by gradual slowdown, with oil energy accounting for 99% of emissions, of which kerosene contributed the highest proportion and exhibited the greatest increase; 2) The decoupling index displayed an "M" curve fluctuation, indicating an initial deterioration followed by improvement, reflecting an unstable decoupling status; 3) The introduction of urbanization effects showed that positive drivers include income urbanization, spatial urbanization, transportation intensity, and industrial structure effects, while negative drivers encompass energy intensity, population urbanization, and energy structure effects. Among these, the paramount factor driving the increase in carbon emissions is income urbanization effect, whereas the paramount factor curbing carbon emissions is energy intensity effect. Finally, policy recommendations are proposed for carbon emission reduction in the transportation sector of Hainan Province.