Thank you, Chris. Good morning. I will now be discussing the future of the environmental impacts caused by noise and emissions which are associated with the aviation industry. This will include a thorough examination of what developments the aviation industry will undertake to reduce, limit or eliminate the impacts of these factors on the environment. There are numerous factors that can reduce the impacts of aviation emissions. In 2006, the aviation industry accounted for 6.1 million tons of CO2, which was about 7.7% of all transport emissions, however one must not forget that the aviation industry is an ever increasing business, with the number of air travel passengers expected to double in the next 20 years (Australian Academy of Science 2009).
One of the most debated aspects that might significantly reduce these emissions especially during flight and take-off is the use of biofuels. According to the Organization for Economic Co-operation and Development (2012), a new fuel, called 'bio-SPK', which is bio-derived synthetic paraffinic kerosene, can be mixed with kerosene at a ratio of 50:50 without any requirements of engine and fuel system modifications to aircraft. However, a significant problem with the use of biofuels is the size of land it will take to grow on a large scale, which is necessary because of the before-mentioned increase in future air passengers. This might cause the locals to compete for land and water use, especially considering that the global population is expected to rise by another 2-3 billion by 2050 (Organization for Economic Cooperation and Development 2012).
Another alternate fuel which can effectively be used in aircraft is hydrogen. There are huge advantages in using this to power aircraft; the main one is its non-polluting properties, since its only by-product is water (Liden n.d.). This will also help to prevent the reduction of fossil fuels and hence carbon emissions, however since burning Hydrogen emits water it is not beneficial to use for high altitude aircraft since the atmosphere high up is naturally dry. Also, there are currently no efficient methods to produce this gas given modern technologies, which creates excessive costs, probably the main reason why it is not commonly used (Wikipedia 2013). Since technology progresses on a daily basis, one can safely assume the near future will bring the knowledge and technology for cheaper and more efficient ways to produce hydrogen on a large scale.
The advance in technological and engineering knowledge and abilities has led to a substantial increase in techniques and systems that can help reduce the impacts on the environment, such as aircraft and engine designs. Not only do better designs reduce the carbon emissions, they also reduce the noise at take-off and landing. As an example, the LEAP56 program is targeting a fuel consumption reduction of 15%, a noise reduction of 10dB and lower maintenance costs, which is achieved by having an advanced turbofan ready by 2015 (Creedy et al. 2008, p. 188). Furthermore, by having a better aerodynamic aircraft design, drag will be reduced, resulting in more speed conservation and hence less need for more thrust, subsequently reducing the amount of fuel used. Not only will this lessen the cost of fuel for each flight, it will also lower the average carbon emissions into the atmosphere for every flight. This small step, along with other techniques that have already been discussed and that will be mentioned later, will contribute to protecting our environment at both local and global levels.
There has been much debate about whether aircraft should travel higher in the stratosphere (Australian Academy of Science 2009). The Australian Academy of Science (2009) discusses that a huge disadvantage of this would be the water vapour emitted into the naturally dry stratosphere, which would greatly contribute to the greenhouse effect. Nevertheless, it would reduce the amount of fuel needed, mostly because of the low air density which increase the aerodynamic efficiency due to less drag. Since most tempestuous weather occurs low in the atmosphere, flying at greater altitudes is also safer (Annenberg Learner 2013).
One of the latest aircraft that extremely efficiently incorporates newest technological advances is the 787, also known as the Dreamliner, which is to replace the 767 in the model line-up (George 2012). George (2012) states that 'Boeing 787 engineers took on large-scale technology risks in designing this aircraft. Their goals included a 20% reduction in fuel burn, a lighter weight airframe and 30% lower maintenance costs than the 767'. Also, according to the Australian Academy of Science (2009), the 787 design reduces noise levels by 10dB when taking off and landing. In the near future, air companies such as Boeing and Airbus should plan to consider using solar, electrical or even hydrogen powered aircraft to prevent the further depletion of the ozone layer due to carbon emissions and to reduce noise. One major disadvantage is the cost of constructing, maintaining and operating these.
Currently, the Aviation Industry majorly impacts the environment, the main and potentially most destructive effect being the carbon emissions, which have been linked to global warming but also ozone depletion. Tourism Concern estimates that by 2015, half the annual damage of the ozone layer will be caused by the aviation industry, which can only be prevented if the issue is taken seriously and immediately acted upon (Srinivas 2001). There are numerous improvements the aviation industry is undertaking or planning, such as more efficient engines that use less fuel to reduce the carbon emissions, better aerodynamic aircraft designs that reduce the amount of drag during the flight, and the introduction of alternate fuels that are more efficient in terms of cost, consumptions and emissions. Thank you for listening, we hope to give you an insight into the complications associated with aviation and the environment and how the aviation industry manages and constantly tries to improve these.