Mengesha Yayo (PhD)Kaleab Enyew2023-12-192023-12-192023-06-18http://etd.aau.edu.et/handle/123456789/1091Urban transportation system is a complex system with multiple variables and nonlinear feedback loops and influenced by transportation, social, economic, and environmental factors. Conventional transportation modeling approaches are unsuitable to simulate and evaluate its performance. This paper presents a system dynamics approach based on the cause-and-effect analysis and feedback loop structures. The proposed SD model comprises population, economic development, number of vehicles, environmental influence, travel demand and transport supply. The model runs in Vensim PLE software using the data from Addis Ababa, Ethiopia. The impacts of different policy scenarios on transportation system related carbon emission are analyzed. Ban imports of used vehicle, Energy shift and setting emission standard have the capacity to reduce carbon emission with the magnitude of 17%, 59% and 43% respectively by 2030. The study suggests that a combination of policies to achieve a low carbon and climate-friendly transport sector which will result a 74% decrease in carbon emission by 2030entransport, carbon emission, system dynamics, Addis AbabaThesis