The contemporary world is known for and proud of its rapid technological development and advancement of science. However, the fast-progressing modernization carries a long list of negative impacts in addition to various benefits. One of the main disadvantages of the speedy technological progress is the pollution of the environment. Regardless of its obvious effects, the pollution had been majorly ignored by the humankind for centuries. Today, it is one of the most frequently discussed global concerns. However, in spite of all the world’s efforts to improve the state of the environment, the damage is done faster than it is addressed.
As a result, the environmental issues on our planet continue to persist. Among all other industries, aviation tends to create negative environmental impacts in a variety of spheres as it pollutes soil, and water aggravates the greenhouse effect due to emissions and also generates noise pollution. This paper attempts to provide a detailed and reliable report concerning the environmental impacts of aviation and different types of pollution that occur because of the use of more powerful aircraft engines, the rapid growth of air travel, greenhouse gas emission, noise pollution, land exploration to build new airports, aircraft waste, and graveyards. The costs and benefits are compared and it is concluded that currently, the efforts to minimize the damage are insufficient and outweighed by the adverse effects.
Rapid Growth of Air Travel
Air travel is known as the fastest and a rather safe way to transport passengers. The main problem it faces currently is its high price. The industry is actively working on this problem as the goal is to maximize the number of people able and willing to afford air travel. According to the data released by the International Air Transport Association (IATA) (2014), the number of people using airborne modes of transportation is anticipated to demonstrate a steady growth of about 4% a year. As a result, as stated by IATA (2014), by 2034 the number of aircraft passengers is likely to exceed 7 billion. For the comparison, the number of passengers who preferred air travel in 2014 estimated 3.3 billion people (IATA, 2014). That way, the overall quantity of aircraft passengers is expected to double within the next two decades.
The growth of air travel is happening all around the world; however, some countries show the most rapid tendencies for development. For instance, IATA (2014) projects that such states as Brazil, India, China, Indonesia, and the USA will become the leaders in air travel trends by 2034. Each of these countries is likely to have several hundred thousands of new passengers within the new two decades. Besides, the rapid growth of the popularity of air travel is forecasted to occur in Africa and the Middle East.
Even though these tendencies are positive in terms of employment, connectivity, and job creation, one must not forget how dangerous the increased activity of aircraft will turn out for the environment. The negative environmental consequences of the growing use of air travel (both current and future) are recognized. As a result, in response to the environmental challenges, the air travel industry has three main goals to follow in order to minimize the damage it causes – the industry agreed to improve the fuel efficiency at least by 1.5% annually till 2020, to cap the net emissions due to the carbon-neutral growth, and, finally, to reduce the net emissions significantly by the year of 2050 (in contrast to those of 2005) (IATA, 2014).
More Powerful Aircraft Engines
The engines of aircraft function similarly to the engines of land-based vehicles. They require fuel to work properly, and as a result, planes pollute the atmosphere just like automobiles. The first airplanes appeared relatively recently – about a hundred years ago invented and promoted by the Wright brothers, and immediately started to gain popularity among the population of the earth (Green, 2003). Consequently, the number of airplanes produced to transport cargos and people grew very quickly, and so did their power and size.
The core function of the aircraft engine is to provide thrust that moves the vehicle forward. The development of aircraft engines happened very fast and in several decades after the invention of the first airplanes, the scientists began to work on the engines allowing the machines to cruise at sonic speed. The first and second world wars served as the catalysts that facilitated the development of aircraft engines as the military power of airplanes is huge. At the same time, the pollution and disruption the airplanes cause to in the atmosphere are obvious as one can easily notice the distinct trail behind a moving plane.
The harm produced by the aircraft engines is discussed in the Kyoto Protocol that obliges the complying countries to work on the reduction of the emissions of various gases released by the engines. As reported by Green (2003), the aircraft engines initially used to release “a mixture mainly of soot and unburned hydrocarbons but containing also carbon monoxide and a mixture of nitric oxide (NO) and nitrogen dioxide (NO2) collectively termed NOx” (p. 284). However, in the middle of the 1990s, the International Civil Aviation Organization (ICAO) developed a set of standards that required the aircraft engine manufacturers to improve combustion efficiency by means of combustion chambers minimizing the amount of unburnt hydrocarbons, soot, and carbon monoxide released by the engines.
Emission of the engines is measured based on several phases of their activity such as taking off, moving, landing, and generating a takeoff thrust, and is determined by the pressure ratio of the engine (Green, 2003). Today, the environmental impact and the level of pollution of the aircraft engines are researched and addressed with the help of computer simulations designed to recreate the work of various engines without actually using them and generating more pollution. This approach is not only environmentally friendly but also cost-effective because using the computers is cheaper than fueling and launching real engines.
Greenhouse Gas Emission
Compared to many other industries, aviation can be called relatively small. At the same time, the negative environmental impact it produces is extremely powerful. David Suzuki Foundation (2014) noted that if all the human activities causing climate change on the planet are counted as 100%, the environmental effects of aviation would comprise 4 to 9% of it. Regardless of all the reduction practices and policies, the environmental impact of aviation continues to increase. For instance, the last 25 years demonstrated an 83% growth of carbon dioxide (CO2) emissions (David Suzuki Foundation, 2014).
As it was mentioned earlier, all means of transportation (air, maritime, road, and rail) tend to discharge gases and particles that cause the greenhouse effect. However, air transportation is the leading mode in terms of the amount of emissions. The formula of the harmful emissions is simple and does not differ from those of the other types of transport: while moving, an airplane engine burns jet fuel; at the same time, carbon released during the reaction binds with oxygen in the air and forms CO2 (David Suzuki Foundation, 2014). Also, the other substances the burnt fuel releases are soot, sulfate, vapor, and nitrous oxides.
That way, compared to the road, rail, and maritime transport, aircraft produces the largest amounts of emissions and also has the worst environmental impact par passenger kilometer (meaning that none of the advantages this kind of transport provides can outweigh the environmental damage it produces). Moreover, apart from all the standard negative effects generated by aviation, it has a special characteristic that makes it stand out among the other kinds of vehicles not only based on the amount of emissions. The peculiarity of aircraft is that the emissions it generates are released in the upper layers of the atmosphere. These emissions are responsible for “a series of chemical reactions and atmospheric effects that have a net warming effect” (David Suzuki Foundation, 2014, para. 5).
Another significant feature of aircraft in terms of its environmental impact is the contrail that is the long lines seen in the skies behind the moving planes. Contrails consist of drops of water that turn into ice under the low temperatures of high altitudes (David Suzuki Foundation, 2014). As the contrails may stay in place for hours and occupy quite a widespread area, they are harmful because of their capacity to create a net and trap warm air preventing it from leaving the atmosphere and this way contributing to global warming. Besides, the researchers found that contrails left by the aircraft at night as especially harmful as those created during the day may reflect the sunlight and relieving some of the heat (David Suzuki Foundation, 2014).
Noise Pollution
The noise started to be recognized as one of the primary problems caused by aviation long before the environmental pollution. It is possible that this tendency was caused by the fact that noise pollution is an immediate effect, while the emissions, greenhouse effect, and global warming started to become visible after decades had passed. Noise pollution does not produce any actual destructive impact on the environment, and its effects do not last long. However, the main harmful aspects of noise have social and psychological characters. The individuals who live close to the airports often suffer from a variety of issues caused by noise pollution; among them, there are problems with communication, sleep disturbance, nervousness, learning and perception issues, and some other psycho-physiological problems (Eurocontrol, n. d.).
Noise pollution as well as its impacts on humans have been studied for decades and are not taken lightly. There exists an International Noise Model that estimates and simulates the levels of noise caused by various types of aircraft (Eurocontrol, n. d.). This Model helps the city planners to visualize the noise impact and determine which areas could be unsuitable or harmful for the inhabitants due to the airports located nearby. The level of noise in the communities suffering from noise pollution is measured using an international standard scale in A-weighted decibels – the units that indicate the impact of noise on people (Eurocontrol, n. d.).
Besides, noise pollution is estimated using such measurements as “perceived noise” and “effective perceived noise” also reflected in decibels. These scales differentiate between types of noise according to its various frequencies and duration (Eurocontrol, n. d.). The scientists do not have an agreement as to which of these two scales is more appropriate since both are used equally by different researchers. Also, there is the third scale called Lden that is widely used by the European Community. It indicates the day-evening-night level of noise in A-weighted decibels.
Noise produced by aircraft is extremely loud. For example, a sound of a person speaking in a normal voice equal 60 to 70 dB (A), whereas the sound of a busy street is approximately 78 to 85 dB (A), a chainsaw makes a noise of about 120 dB (A), and a taking off airplane is as loud as 140 dB (A) if the person who perceives it stands about 75 feet away from it (Eurocontrol, n. d.).
For the management of aircraft noise, all the commercial airlines are to follow the rules developed by the ICAO. These standards outline the norms and regulations as to the design and use of aircraft based on its types. The rules were first introduced in 1971 and have been gradually becoming stricter as the years pass. Currently, the options for noise mitigation include the careful use of land to plan the noise areas away from the inhabited districts, the reduction of engine noise at source, and operational restrictions (Eurocontrol, n. d.). These points are the main bases for the noise reduction policies. However, there are some other procedures employed to minimize the noise pollution; they are the limiting of operation at night, cutting the unnecessary use auxiliary engines, planning the air routes so that they do not overfly the areas with schools and hospitals, noise level monitoring, to name a few (Eurocontrol, n. d.).
The Benefits of Aviation
Along with all the disadvantages and negative impacts, aviation is responsible for a wide range of benefits that serve as a powerful force that moves humanity to greater progress, safer travel, a higher level of convenience, faster communication and transportation. One could say that the practical use of air travel and all the advantages it carries for the humanity on various levels could outweigh the damage it produces and that the outcomes such as the environmental impacts could be considered as the necessary sacrifice for the sake of convenience and progress.
Fast Technological Progress
In reality, aviation is one of the fastest progressing industries in the whole world. Such tendency occurred due to the nature of air travel that differs from that of the ground vehicles as the airplanes cannot be refueled during a journey and, as a result, are to carry a large amount of the required fuel inside (ATAG, n. d.). Consequently, the aircraft developers and manufacturers are faced with an ongoing challenge to ensure a life-long improvement of the airborne vehicles in order to optimize such aspects of air travel as speed, costs, and safety. In other words, the fact that the airplanes are to carry all of the fuel along during the trips creates a great range of difficulties for the industry because
- the fuel is very costly (it comprises about 30% of the operating expenditures of an air vehicle) and therefore, the amount of it an airplane consumes makes a direct impact on the pricing of the air travel;
- the fuel is heavy, and it tends to increase the overall weight of an airplane which, in turn, impacts the efficiency of the vehicle and the speed of air travel;
- finally, the more fuel is used by the plane, the more CO2 it produces to harm the environment (ATAG, n. d.).
That way, the constant technological progress in the industry is dictated by multiple causes, and due to that, the airborne vehicles become better, lighter, safer, faster, and more efficient by the year. The financial stimuli to make aviation a more efficient and productive industry go hand in hand with the environmental concerns that arose as soon as the industry leaders realized that airborne vehicles, airports, and engines harm the world around polluting soil, water, and air.
Ongoing Work on the Environmental Safety of Air Vehicles
The manufacturers of aircraft and engineers are involved in daily work on the improvement of the air vehicles. Most importantly, this work has been fruitful, and its results continue to impress the scientists in terms of rapid progress.
It is important to notice that a little over a hundred years ago the mere idea of air travel was considered an unrealistic fantasy. Today, the aviation has come a long way in technological development and capabilities. As soon as the issue of air pollution and emissions became known as one of the most harmful outcomes of air travel, the industry focused on the decoupling of this impact. As a result, these days, while the air traffic growth worldwide estimates by 5% annually, the increase in the emission production is only 3% (ATAG, n. d.). Each new generation of aircraft offers more and more benefits in terms of environmental safety and more efficient fuel combustion.
Besides, the aerodynamic efficiency is another way to address the problem of the environmental safety of aircraft. The outer appearances of the airplanes are regularly modified for the improvement in their aerodynamic capabilities. For example, the new types of aircraft wings equipped with a special wingtip device allow the vehicles to consume less fuel (ATAG, n. d.). All in all, the aircraft manufactured within the last decade has an impressive efficiency. For instance, Boeing 787 and Airbus 380 require about 3 liters of fuel per 100 passenger kilometers, which makes them on average, more efficient than group-based vehicles such as compact cars (ATAG, n. d.). This benefit looks even more amazing if the speed of the two types of vehicles is compared.
Costs Are Still Greater Than Benefits
Without a doubt, the effort of the aircraft manufacturers and scientists who work on the improvement of the airborne vehicles and their engines is starting to pay off. The aircraft developers have been successful in the reduction of emissions and the increase of aerodynamic capacities of the airplanes helping to reduce the amount of fuel they consume. However, the range of adverse effects of the environmental pollution caused by the development of aviation as an industry is much wider than the number of areas where the scientists are attempting to minimize the damage.
Apart from the engines with inefficient fuel combustion that contributes to the development of the greenhouse effect and the noise pollution, there are such harmful environmental impacts of aviation as the retired airplanes and aircraft waste. For decades, ever since the airplanes began to become a significant aspect of the life of our society, the remains of aircraft, as well as the machines that are no longer in use, have been stored in the so-called “graveyards”. Being too large to be utilized in any other way such as burning or burying, aircraft is doomed to end its days in the middle of deserts such as Mojave left to decay (Mouritz, 2012).
Another significant negative impact is caused by the land exploration for the construction of the new airports. For instance, in his book called “Exploring Environmental Issues: An Integrated Approach” David Kemp (2004) discusses the cases in Australia and Japan where the land exploration for the new airports faced a serious social issue of opposition from the public and the environmentalists as well as a practical problem of lack of land. The exploration in Sydney took over a part of Botany Bay, a home to multiple ecosystems and several Aboriginal peoples. As for the campaign in Osaka, it resulted in reclaiming some territory from the sea and building an airport on a specially created artificial island (Kemp, 2004).
Conclusion
The environmental impacts of aviation are multiple and different. This paper discussed some of them and reported that all aspects of air travel are as dangerous for the environment as they are beneficial for the people and economies. Unfortunately, the damage produced by this industry has been overlooked for decades. Today, when the consequences are visible, the environmentalists and the aerospace industries cooperate to minimize the level of harm in the future as the popularity of air travel grows rapidly and so does its negative environmental impact. However, the damage produced by aviation affects many more areas than the scientists can address today, so regardless of their effort the danger remains and persists.
References
ATAG. (n. d.). Technology. Web.
David Suzuki Foundation. (2014). Air travel and climate change. Web.
Eurocontrol. (n. d.). Environmental issues for aviation. Web.
Green, J. E. (2003). Civil aviation and the environmental challenge. The Aeronautical Journal, 281-299.
IATA. (2014). New IATA Passenger Forecast Reveals Fast-Growing Markets of the Future. Web.
Kemp, D. D. (2004). Exploring Environmental Issues: An Integrated Approach. Hoboken, NJ: Taylor and Francis.
Mouritz, A. P. (2012). Introduction to aerospace materials. Reston, VA: American Institute of Aeronautics and Astronautics.