Environmental Engineering Reference
In-Depth Information
Few people would want a world without the possibility of air travel. While this is an
unlikely prospect, a world of unlimited air travel is likely to be equally unacceptable.
At issue is not whether or not there should be aviation, but at what point for differ-
ent regions and nations the disadvantages of additional air capacity outweigh the
advantages. How sufficiency should be determined in this context and who should
determine it are also key issues.
In 1999, following a request from the United Nations (UN) International Civil
Aviation Organization (ICAO) and the parties to the Montreal Protocol on Sub-
stances that Deplete the Ozone Layer, the UN Intergovernmental Panel on Climate
Change (IPCC) published an important report on the atmospheric impacts of avia-
tion (IPCC, 1999). The IPCC noted that aviation has experienced rapid expansion
as the world economy has grown (IPCC, 1999). Passenger traffic (expressed as reve-
nue passenger-kilometres) has grown since 1960 at nearly 9 per cent per year, 2.4
times the global average gross domestic product (GDP) growth rate. Freight traffic,
approximately 80 per cent of which is carried by passenger aircraft, has also grown
over the same time period. Although the rate of growth of passenger traffic has
slowed to about 5 per cent in 1997 as the industry is maturing in some parts of the
world, growth rates of 5 per cent per year are expected to continue for the next 10 to
15 years (IPCC, 1999).
As the GDP of a country increases, there tends to be a shift towards faster
modes of passenger transportation (Schafer and Victor, in Clarke, 2001, p2). In the
US, with no large-scale passenger rail infrastructure and little political will to con-
struct infrastructure for high-speed rail, aviation is likely to continue to be the pri-
mary high-speed transportation mode for the foreseeable future (Clarke, 2001, p2).
In smaller island states scattered throughout Asia, where the centres of commerce
and trade are separated by stretches of ocean, aviation offers a means of transporta-
tion that is significantly faster than marine ship. Similarly, in Africa and South
America, aviation offers a means of high-speed transportation that is independent of
terrain for linking centres of commerce and trade. Similar comments might be made
of China, the aviation market of which Boeing expects to grow at twice the average
rate over the next 20 years (Anon, 2000). In general, then, as most economies develop
and the GDP of these economies increase, there is likely to be increased passenger
air transportation (Clarke, 2001, p2). This conclusion is supported by a second
study that indicates that the travel growth for a country averages 1.7 per cent above
the forecasts for economic growth as measured by the GDP (Anon, 2000).
The environmental consequences of contemporary aviation are significant. Of
particular note at the global scale is the contribution of aviation to global climate
change. Although global aviation emissions of carbon dioxide (CO
2
) are a small per-
centage of carbon emissions worldwide, they are still roughly equivalent to the car-
bon emissions of industrialized countries such as Canada and the UK (US GAO,
2000). More locally, aircraft and airport operations generate noise from take-off and
landings, engine testing, surface transport and construction, so that noise is widely
considered to be one of the most serious environmental problems of aviation. Although
perception of noise is subjective, it can contribute to sleep disturbance problems and
other related physiological and psychological effects (Morrell et al, 1997; Bullinger
et al, 1999). Other airport-related environmental issues include contaminated land,
ground and surface water at airports arising from jet fuels, aircraft de-icing operations
