A Two-Phase Model for the Evaluation of Urbanization Impacts on Carbon Dioxide Emissions from Transport in the European Union

Urbanization has contributed to an increase in the transport activities, and thus to a greater degradation of air quality. The urban indicators in the European Union (EU) countries have different negative effects on air quality. That is why the EU has been making special efforts. Although in recent years special attention has been paid to the analysis of the Environmental Kuznets Curve (EKC), the main problem related to this analysis is the choice of air quality indicators. In order to overcome this problem, a two-phase model was developed. In the first phase, extreme values of the impact of (urban) inputs on the output (carbon dioxide (CO2) emissions) variable of the EU countries from 2000 to 2014 are determined, using the methodology of artificial neural networks (ANN), in order to select an input variable. In the second phase, starting from the selected variable, a cluster analysis of the EU countries is applied in order to examine the legality of the EKC. Based on the obtained results, it is shown that the connection between the methodology of ANN, cluster analysis and the laws of the EKC can be used to examine the impact of widely available urban indicators on various air quality indicators.