Spatial Aggregation of Worldwide Air Transportation Networks

Air transportation, as the dominant mode for long-distance passenger travel, plays a critical role for a sustainable and greener future. Therefore, the analysis and understanding of air transportation systems is crucial. Air transportation networks and their layers as induced by spatial aggregation were investigated. Existing studies analyze network layers individually, ignoring interactions or couplings between the layers. This research aims to provide a unified understanding of the transitions among network layers, based on the worldwide air transportation networks for the year 2015. Aggregated network instances at six different levels were derived. While few nodes are important at all levels of aggregation, others only become important for few aggregation levels. Moreover, analysis results of different layers’ robustness are reported.