International air network structures and air traffic density of world cities

This paper examines international air passenger and cargo flows within and among Asia, Europe, and America, and the degree of air traffic density for major cities worldwide, using a basic gravity model composed of GDP, population, distance, and several dummy variables. The results reveal that many cities are strengthening their position as international air transportation hubs, especially: Tokyo, Hong Kong, Singapore, London, Paris, Frankfurt, Amsterdam, New York, and Miami. Finally, the results show that the air traffic density of three cities, Seoul, Hong Kong, and Amsterdam, is growing at an extraordinary rate.