International air transport: environmental impacts of increased activity levels

This chapter reviews the literature on the environmental impacts of aviation, discusses trends in emission patterns and comments upon how the external cost of aviation is estimated in various studies. The purpose of the chapter is to assess how developments in the aviation sector in the last few decades have impacted on the environment, and what this means for transport and environmental policy. The chapter explores how hub-and-spoke networks can lead to environmental benefits because of economies-of-scale in environmental terms. Passengers are concentrated on a few routes, so that larger aircraft may be used. But transfer passengers fly longer distances, and take off and land twice, so that they have a relatively large environmental impact. The chapter explores policy instruments, such as compensation regulation. A number of factors are examined: noise (people are asked what they are willing to pay to experience less aviation noise); emissions (damage to human health, damage to buildings, reduced visibility, damage to forests, crops and fisheries); and accidents.