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- Aviation industry large contributor to global greenhouse gas emissions - that will only increase as flights increase
Environment Exts - Aviation Industry keyAviation is key to our carbon footprint - any statistics that show low percentages are misleading and do not take multipliers into accountClark 10 (Duncan Clark is a consultant editor on the Guardian environment desk. He has written and edited a number of books on environmental and technology topics as well as working at BBC Worldwide and 10:10. “Aviation Q&A: the impact of flying on the environment” http://www.guardian.co.uk/environment/2010/apr/06/aviation-q-and-a April 6, 2010) FOSTER Does air travel really have a big environmental footprint? There's no way around the fact that flights are bad news for the environment. It's not just that planes are worse than most other forms of transport in terms of the impact of greenhouse gases per passenger mile. Just as important is the simple fact that flying allows us to travel a far greater number of miles than we otherwise could. Thanks to these two factors, individual trips by air can have a remarkably large carbon footprint – which helps explain why aviation has become such a heated issue in the climate change debate. What is the total impact of flying on the climate? As the aviation industry is usually keen to point out, planes account for only around 1.5%–2% of global CO2 emissions. However, this figure is somewhat misleading. For one thing, most flights are taken by the wealthy, so in developed countries the slice of CO2 emissions caused by flying is higher – around 6.3% in the UK, according to Department for Transport figures for 2005. Even this figure underplays aviation's environmental footprint, however, and not just because the number of flights has risen since 2005. There are at least three other reasons why 6.3% is likely to be a strong underestimate. First, the total global warming impact of each flight is thought to be around twice as high as the CO2 emissions alone (see 'What's an aviation multiplier?', below). Second, the figures are skewed in favour of British travellers. The standard way to account for the emissions for an international flight is to allocate half to the country of departure and half to the country of arrival. But UK residents take up two-thirds of the seats on the average plane landing at or taking off from a British airport. This means the official statistics are effectively offloading the emissions of British holidaymakers and businesspeople on to the countries they're visiting. Third, the aviation industry causes emissions over and above those of the planes themselves. The processing and transportation of the aviation fuel, and the manufacture and maintenance of planes, airports and support vehicles all create extra carbon dioxide. There's not enough data to say for sure, but it seems likely that aviation's true impact in the UK is around 13%–15% of total greenhouse gas emissions. If that still sounds fairly low, compared with the massive amounts of attention heaped on aviation by climate change campaigners, bear in mind that most people in the UK don't regularly fly. The average British resident takes a short-haul leisure flight only every two years, and a long-haul leisure flight only every five years. In other words, the air travel of a minority of regular flyers causes a substantial slice of UK emissions. Is the UK government's aviation policy compatible with its carbon targets? It's very hard to reconcile the British government's plans for increased aviation capacity with its plans for carbon cuts. The UK is seeking to reduce its emissions by 80% by 2050, relative to 1990 levels. At the same time it predicts a rise in the number of flights sufficient to use up more than half of the remaining 20% of emissions. What about greener planes? A number of technologies designed to reduce the environmental impact of flying have been researched, tested and implemented. However, compared with greener cars, where the technologies are proved and the carbon saving huge, the potential for eco-friendly flying looks rather limited. There will be some further gains in engine efficiency over the coming decades, and larger planes with more seats will allow slightly lower emissions per passenger. But there is nothing in the pipeline with the transformative potential of the electric car. The problem is that electric motors can't produce enough power to get a plane off the ground, so the only alternative to regular kerosene-based aviation fuels are special kinds of biofuels. These aren't an ideal solution, since biofuels can be environmentally problematic in themselves, and anyhow it would take a huge chunk of the world's arable land to grow enough crops to fuel all the world's planes. (A back-of-the-envelope calculation suggests it might require as much as a fifth of all cropland.) What can individuals do? For anyone concerned about their contribution to global warming, cutting back on air travel is an obvious goal. This might mean giving up flying altogether or it might mean taking fewer flights and picking destinations that are closer to home. It's true that short flights tend to be more harmful to the climate per mile travelled than long-haul flights are (because they have more empty seats, and because taking off and landing burns more fuel than cruising) but this doesn't change the fact that the further you travel, the greater the emissions that will result. If you do fly, you can in theory make some small difference to the carbon impact by favouring day-time flights. This at least means that any contrails (see 'What's an aviation multiplier?' below) caused by the plane will reflect some sunlight away from the Earth in addition to locking warmth into the atmosphere. Also consider limiting your luggage. Finally, you might want to consider which airlines you use. People often assume that budget flights are somehow more eco-unfriendly than expensive ones. In fact, the opposite tends to be true. Budget airlines pack more passengers on each flight and typically have younger, more fuel-efficient fleets than longer-established airlines. Indeed, the least eco-friendly tickets of all aren't the cheapest but the most expensive. Business-class and first-class seats take up more space on the plane, thereby reducing the number of people who can fit on each flight. Is it really greener to go by train? As a rule, taking the train instead of the plane will substantially reduce your carbon emissions – perhaps by a factor of five to ten on a domestic trip. The benefits will be somewhat reduced as the journey gets longer. That's partly because shorter flights are more polluting per passenger mile than longer ones, but it's also because long train journeys usually necessitate sleeping onboard. Sleeper cars usually carry fewer passengers than regular carriages, so their emissions per passenger are higher. If, as is common in some countries, the train is powered by diesel rather than electricity, then the emissions will typically be higher still. Indeed, an old diesel sleeper train travelling a long distance might emit nearly as much CO2₂per passenger as a plane. Even then, the train will typically be greener once you consider the plane's non-CO2 warming effects, but the fact remains that long-haul rail is not by any means inherently eco-friendly. Unfortunately, almost every long-distance train journey will cost you far more than flying would. Indeed, the difference in price is often so great that for some unavoidable trips it would arguably make sense to take the plane and spend the savings on something more environmentally beneficial than a train ticket, such as insulation at home. What's an 'aviation multiplier'? The impact of planes on the climate is complicated and not perfectly understood. The CO2 emissions are straightforward enough, but plane engines also generate a host of other "outputs", including nitrous oxide, water vapour and soot. At flying altitudes in the upper troposphere and lower stratosphere, these outputs produce a range of climatic effects, multiplying the plane's environmental impact. For example, nitrous oxide causes the formation of ozone — a greenhouse gas that warms the local climate — but at the same time undergoes reactions which destroy methane, thereby removing another greenhouse gas from the atmosphere. Even more complicated is the impact of soot and water vapour, which together can cause contrails (vapour trails) and in cold air can lead to the formation of cirrus clouds. The science surrounding this topic is not yet rock solid, but researchers believe that contrails add to the greenhouse effect – especially at night, when their tendency to stop heat escaping from the Earth isn't offset by their tendency to reflect incoming sunlight. Today, most experts favour an aviation "multiplier" of around two. In other words, they believe that the total impact of a plane is approximately twice as high as its CO2 emissions. The exact multiplier, however, will always depend on the individual plane, the local climate and the time of day. Aviation has a multiplier effect on the world's carbon footprint - it emits CO2 from jet emissions but also emits water vapor, which creates heat-trapping cloudsFleming 9 (Aviation and Climate Change: Aircraft Emissions Expected to Grow, but Technological and Operational Improvements and Government Policies Can Help Control Emissions June 8, 2009 Statement of Susan Fleming, Director, Physical Infrastructure Issues. June 8, 2009 This is a GAO report. LexisNexis.) FOSTER Emissions from a variety of human-generated sources, including commercial aircraft, trap heat in the atmosphere and contribute to climate change. During flight operations, aircraft emit a number of greenhouse gas and other emissions, including carbon dioxide, nitrogen oxides (NOx), soot, and water vapor. Figure 1 shows the primary emissions from commercial aircraft. Carbon dioxide emissions from aircraft are a direct result of fuel burn. For every gallon of jet fuel burned, about 21 pounds of carbon dioxide are emitted. Reducing the amount of fuel burned, therefore, also reduces the amount of carbon dioxide emitted. Water vapor emissions and certain atmospheric temperature and humidity conditions can lead to the formation of contrails, a cloudlike trail of condensed water vapor, and can induce the creation of cirrus clouds. Both contrails and cirrus clouds are believed to have a warming effect on the earth's atmosphere. Aircraft also emit other pollutants that affect local air quality. Finally, airport operations are sources of greenhouse gas and other emissions, which we are not examining in this report. Emissions from aviation key to global environmental problems - it will only get exponentially worse in the status quo as aviation industry continues to increase their emissions while other sectors decrease their emissionsWaitz et al 4 (Ian - professor and director of Partnership for AiR Transportation Noise and Emissions Reduction @ Massachusetts Institute of Technology, "Report to the United States Congress: Aviation and the Environment", December 2004 http://web.mit.edu/aeroastro/partner/reports/congrept_aviation_envirn.pdf pg.3) Foster Aviation is a critical part of our national economy, providing for the movement of people and goods throughout the world, enabling our economic growth. In the last 35 years there has been a six-fold increase in the mobility provided by the U.S. air transportation system. At the same time there has been a 60% improvement in aircraft fuel efficiency and a 95% reduction in the number of people impacted by aircraft noise. Despite this progress, and despite aviation’s relatively small environmental impact in the United States, there is a compelling and urgent need to address the environmental effects of air transportation. Because of strong growth in demand, emissions of some pollutants from aviation are increasing against a background of emissions reductions from many other sources. In addition, progress on noise reduction has slowed. Millions of people are adversely affected by these side effects of aviation. As a result of these factors and the rising value being placed on environmental quality, there are increasing constraints on the mobility, economic vitality and security of the nation. Airport expansion plans have been delayed or canceled due to concerns over local air quality, water quality and community noise impacts. Military readiness is challenged by restrictions on operations. These effects are anticipated to grow as the economy and demand for air transportation grow. If not addressed, environmental impacts may well be the fundamental constraint on air transportation growth in the 21st century. The concerns extend well beyond American shores. For example, within the European Union (EU) the climate impacts of aviation are identified as the most significant adverse impact of aviation, in contrast to the United States and many other nations where air quality and noise are the current focus of attention. As a result, there are increasing EU calls for regulation—trading, taxes and charges, demand management and reduced reliance on aviation—even though there is large uncertainty in the understanding of the climate effects of aircraft and appropriate means to mitigate these effects. Despite the importance of this issue, the United States does not have a significant research program to assess the potential impacts of aviation on climate. This may put the United States at a disadvantage in evaluating technological, operational and policy options, and in negotiating appropriate regulations and standards with other nations. The international concerns will continue to grow with the strong increase in air transportation demand anticipated for Asia. Immediate, focused action is required to address the interdependent challenges of aviation noise, local air quality and climate impacts. Not acting, as stated above, will not only affect millions of Americans living near airports but will adversely impact the vitality and security of our nation. A national vision and strategic plan of action are required. Aviation industry large contributor to global greenhouse gas emissions - that will only increase as flights increaseSgouridis et al 11(Sgouris, Associate Professor at the Masdar Institute of Science and Technology; PHILIPPE A. BONNEFOY, Postdoctoral Associate in the Department of Aeronautics & Astronautics at MIT; Dr. R. John Hansman, Professor in the Department of Aeronautics and Astronautics at MIT, where he is Head of the Humans and Automation Division, Director of the International Center for Air Transportation. Transportation Research Part A: Policy & Practice; Dec2011, Vol. 45 Issue 10, p1077-1091.) cass Historically, air transportation activity has exhibited significant growth (Fig. 1). North America and Europe have grown at an¶ average annual rate of 5.7% and 5.0% respectively over the last 20 years. Asia-Pacific has exhibited significant growth (i.e. 8.8%)¶ and is now reaching traffic levels comparable to Europe. Impressive growth has also been observed in the Middle East with 13%¶ annual growth between 2000 and 2007. Schafer and Victor (2000) affirm expectations that the impetus for these growth rates¶ for aviation will be maintained using a time-budget model to project growth rates across transportation sectors.¶ However, air transportation activity is also a contributor to greenhouse gas emissions (e.g. CO2, NOx) and future growth of¶ this industry sector is likely to be accompanied with increasing emissions unless significant efficiency improvements and¶ mitigating measures are implemented. The Intergovernmental Panel for Climate Change (IPCC) evaluated the effects of¶ the transportation sector on climate change using scenarios to forecast the demand and emissions of the different modes¶ (IPCC, 1999; Ribeiro et al., 2007). These forecasts were building on work from the United States Energy Information Administration¶ (EIA, 2005), the International Energy Agency (IEA, 2004) and the World Business Council on Sustainable Development¶ (WBCSD, 2004).¶ As shown in Fig. 2, CO2 emissions from air transportation are expected to increase significantly in nominal terms. While¶ the relative contribution of the aviation sector to the global anthropogenic carbon emissions is currently estimated at about¶ 3%, the higher potential for improvements and emission reductions from other sectors are likely to contribute to an increase in the aviation’s relative contribution. The 1999 IPCC report suggests that this contribution may rise to 5% and could reach up¶ to 15% by 2050 (IPCC, 1999).¶ The GHG emissions generated by aviation are not limited to CO2. The IPCC (1999) and Sausen et al. (2005) estimate the relative contribution of CO2 to total green house gas (GHG) effects to be approximately 53%. Lee et al. (2009) present the¶ most recent information on the relative contribution of other GHG gases from the aviation sector and estimate the total radiative¶ forcing from aviation to be 3.5% of total anthropogenic forcing excluding the effect of clouds. The net effect of NOx emissions¶ that increase ozone (i.e. O3) concentrations and decrease methane (i.e. CH4) is estimated at 24%. The effect of contrails is estimated at 21% and the remaining combined effect of H2O, SOx and soot contributes to 2.1% of the total effects.3 These annual impacts of emissions do not address the different life cycles of the gases. Marais et al. (2008) indicate that the long-term effect of carbon emissions, which also happen to have the longest atmospheric life exceeding 100 years, may dominate the effect of other greenhouse gases depending on the evaluation method used and the discount rate. Because of its high relative contribution¶ to GHG effects, its long lasting impacts and the high uncertainty surrounding non-carbon radiative forcing, this paper¶ will solely focus on the CO2 emissions from aviation. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 0.82 Mb. Share with your friends:
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