Airplanes could generate 43 gigatonnes of planet-warming pollution through 2050, consuming almost 5 percent of the world’s remaining carbon budget, according to a new Center report.
Aircraft emit staggering amounts of CO2, the most prevalent manmade greenhouse gas. In fact they currently account for some 11 percent of CO2emissions from U.S. transportation sources and 3 percent of the United States’ total CO2 emissions. All told, the United States is responsible for nearly half of worldwide CO2 emissions from aircraft.
In addition to CO2, aircraft emit nitrogen oxides, known as NOx, which contribute to the formation of ozone, another greenhouse gas. Emissions of NOx at high altitudes result in greater concentrations of ozone than ground-level emissions. Aircraft also emit water vapor at high altitudes, creating condensation trails or “contrails” — visible cloud lines that form in cold, humid atmospheres and contribute to the warming impacts of aircraft emissions. The persistent formation of contrails is associated with increased cirrus cloud cover, which also warms the Earth’s surface. Aircrafts’ high-altitude emissions have a greater global warming impact than they would if the emissions were released at ground level.
Alarmingly, aircraft emissions are expected to more than triple by mid-century. But the Center is working to make sure that prediction doesn’t come true: In December 2007 we joined with states, regional governments and other conservation groups to petition the U.S. Environmental Protection Agency to address the effects of aircraft pollution under the Clean Air Act. The agency continued to drag its feet on the issue, so in June 2010 the Center and allies sued the agency for its failure to address global warming pollution from aircraft, ships and nonroad vehicles. The next year a court ruled that the EPA must formally determine whether greenhouse gas pollution from aircraft endangers human health and welfare. When the agency still hadn’t done so nearly three years later, in August 2014 the Center and allies filed a notice of intent to sue it over its failure to reduce global warming pollution from aircraft engines. The next month the EPA announced the beginning of a domestic rulemaking process to determine whether the fast-growing carbon emissions from American aircraft endanger public health and welfare.
In June 2015 the EPA finally released a draft finding that greenhouse gas pollution from America’s aircraft fleet does harm the climate and endanger human health and welfare. But the agency also considered handing off responsibility for airplane emissions to a secretive international aviation organization that, for the past 18 years, has refused to curb aircraft-induced global warming. That agency is now debating setting aviation CO2emissions standards in 2016, but the standards under consideration are woefully insufficient. By as late as 2030, they would likely affect just 5 percent of aircraft — and even then would do next to nothing to lower the industry’s steeply rising emission curve.
The EPA does not have to adopt do-nothing international standards. It has powerful tools: The U.S. Clean Air Act is designed to force the implementation of technological and operational innovation that prevents or reduces carbon pollution. This means adopting operational measures to minimize fuel use and reduce emissions from aircraft; requiring the use of lighter, more efficient airplanes; and producing and using cleaner jet fuels. A recent International Council on Clean Transportation report found that some of the top 20 transatlantic air carriers can drive down emissions by as much as 51 percent using existing technology and operational improvements, and still remain competitive with their better-performing peers.
Finally, in July 2016 — after nine years of delay — the EPA officially acknowledged in a so-called “endangerment finding” that planet-warming pollution from airplanes disrupts the climate and endangers human welfare. But the agency failed to move forward on rules to actually reduce aircraft emissions. The Center’s work to reduce U.S. airplane emissions continues.
Achieving meaningful global action is also critical. That’s why the we urged U.S. climate negotiators to support strong airplane pollution rules in the Paris climate treaty and performed a thorough analysis of the worldwide impacts of pollution from the aircraft sector. Read our report Up in the Air: How Airplane Carbon Pollution Jeopardizes Global Climate Goals.
In 2011, approximately 200 million passengers passed through mainland UK airports. This was a return to growth, following a recent period of decline in passenger numbers and air transport movements between 2007 and 2010. Government forecasts predict that this will rise to 255 million in 2020 and 313 million in 2030.
Airport operations are an important factor in our economy, for tourism, imports, exports and business. However, these benefits must be weighed against the impact air travel is having on the quality of life of increasing numbers of people and on the local and global environment. Noise and air pollution – both from aircraft and from airport ground operations – are a problem for those who live, work and study around airports.
The most immediate impact of aircraft is noise – whether it is the regular rumble of international jets or the buzz of microlights and light aircraft on sunny afternoons. The noise from airborne aircraft is related to air speed. Any fast-moving components, such as propellers and compressor blades, generate noise, as do the exhaust gases of jets. Aircraft are also responsible for an increasing proportion of air pollutant emissions, both at local and global level.
The Government has set up the Airports Commission, chaired by Sir Howard Davies, to look at long-term airport capacity issues in the UK. The Commission is examining the scale and timing of any requirement for additional capacity, focusing in particular on aviation hub issues, and identifying how any need for additional capacity should be met in the short, medium and long term.
The Commission is due to publish its interim report, assessing the most credible options for providing any new airport capacity, by the end of 2013. Criteria that the Commission is using to identify options include strategic, economic, surface access and environment. Environment criteria include air quality and noise. The Commission’s final recommendations are expected by summer 2015.
The International Civil Aviation Organisation (ICAO) is responsible for drawing up aviation noise standards with the European Civil Aviation Conference, and UK standards are set in accordance with these.
Currently the Government only has direct responsibility for aircraft noise management at Heathrow, Gatwick and Stansted. Measures introduced to reduce noise include Noise Preferential Routes and restrictions on night flying. Maximum noise limits for departing aircraft are set and monitored and noise insulation schemes are in operation. Noise from aircraft on the ground is the responsibility of the airport operator. To comply with the EU Environmental Noise Directive, operators of airports with over 50,000 movements a year have been required to draw up Noise Action Plans (under criteria set for this 15 airports are designated in England, three in Scotland and one in N Ireland).
Noise limits have been introduced at the designated airports to cover the period 0700h – 2300h. Airport companies are responsible for monitoring compliance and breaches are subject to a financial penalty. Night flights are restricted between 2300h – 0600h and airports are given quotas of the number of night movements of noisier aircraft allowed to land during these periods.
Environmental Protection UK believes that any developments or alterations to the UK aviation infrastructure, air operations or flight scheduling, should not result in an increase to the night-time or day-time noise exposure of either the general population or of individual communities. Where an increase in exposure is unavoidable, a full package of mitigation measures should be offered to those affected, and the costs of such measure should be met by the aviation industry.
Aircraft engines generally combust fuel efficiently, and jet exhausts have very low smoke emissions. However, pollutant emissions from aircraft at ground level are increasing with aircraft movements. In addition, a large amount of air pollution around airports is also generated by surface traffic.
The main pollutant of concern around airports is nitrogen dioxide (NO2). NO2 is formed by nitrogen oxide (NOx) emissions from surface traffic, aircraft and airport operations. PM2.5 is also of concern, since particulate emissions from jet exhausts are almost all in this fine fraction.
NOx in the lower atmosphere contributes to the production of ozone; ozone in the lower atmosphere is a pollutant, and contributes to global warming. Nitrogen oxides from high-altitude supersonic aircraft are thought to damage the stratospheric ozone layer, the protective layer that filters out harmful radiation from the sun.
The International Civil Aviation Organization (ICAO) sets international standards for smoke and certain gaseous pollutants for newly-produced large jet engines; it also restricts the venting of raw fuels. The latest standards came into effect in 2013 and apply to engine types certified after this date. Reductions in emissions from aircraft engines have generally been lower in recent years than in other sectors, where technologies such as selective catalytic reduction and exhaust gas recirculation have been employed. There are also increasing numbers of larger aircraft movements, which have disproportionately higher emissions than smaller aircraft.
Environmental Protection UK believes that no developments or alterations to the UK aviation infrastructure, air operations or flight scheduling should result in a breach of the EU limit values or UK air quality objectives, or worsen current breaches. Emissions considered must include direct emissions from aircraft, air-side service vehicles and plant, and the surface access required for airports.
Aviation is also a significant source of carbon dioxide emissions, and presents a major threat to Government targets in terms of emissions growth. This is for three reasons, firstly aviation is predicted to grow significantly, secondly emissions at altitude however are thought to have a greater effect on climate change than those at ground level, and finally there is no practical alternative to kerosene fuelled jet engines currently on the horizon. As other sectors reduce emissions aviation is therefore likely to become responsible for a far larger proportion of global climate change emissions.
ADDRESSING AVIATION POLLUTION
Environmental Protection UK is concerned at the potential impact of the apparent ‘predict and provide’ approach that is being taken to air travel in the UK and we would like to see the environmental impacts caused by any expansion reduced or avoided. We will be following the recommendations of the Airports Commission with interest.
We would like to see aviation policies developed in a way which is consistent with the approach used for other transport sectors, and aviation should be fully bedded into an integrated transport policy, rather than being treated as a separate issue.
The Government should also seek to reduce the environmental and social harm arising from aviation through a balanced programme of progressive introduction of improved technology, better operational practice and demand management. Where new infrastructure is required, or where existing capacity is expanded, the mitigation of further environmental and social harm should be seen as a key priority.
Action to reduce the environmental and social harm caused by aviation will require international cooperation. The Government should adopt a leading and active role in international debate, particularly within the European Union, and should encourage the development of radical and innovative solutions.
Environmental Protection UK has been lobbying the Government on aviation pollution, and responded to the consultation on the Draft Aviation Policy Framework, with the response below:
- EPUK response to the Draft Aviation Policy Framework – October 2012 (PDF)
Planning development to meet the projected increased demand in passenger air traffic is also a cause for concern. While emissions from road vehicles are expected to decrease, this will be offset by growth in surface access movements around airport. Increasing capacity in more rural areas will lead to the erosion of tranquillity, loss of habitats for wildlife and increased surface traffic.
The environmental impact of aviation must include the impact of surface access to airports, and given that passengers, employees and goods often travel considerable distances to reach certain airports, this must be considered across the widest possible geographical context.
Where any airport infrastructure development occurs, either as new build or extension to existing infrastructure, surface access infrastructure must be planned, funded and delivered as an integral and wholly necessary part of the project. It should therefore be a condition of any new airport infrastructure development that the necessary surface access infrastructure be in place in its entirety before the airport facility comes into use.
COST AND TAXATION
Under international law, aviation fuel for international flights is exempt from taxation, which means air travel is relatively cheap. This also reduces the incentive for airlines to invest in more efficient aircraft. Aircraft operators are included within the European Union Emissions Trading Scheme. They could be further incentivised via fuel tax (which could be levied for domestic flights). This could:
- ensure airlines pay for the pollution they cause, like other transport operators
- encourage the development of more fuel-efficient aircraft
- help reduce the demand for air travel as other options become more competitive
- be consistent with UK pledges to reduce greenhouse gas emissions from airport operations
Policy should progressively seek an equitable cost/taxation basis across all modes of transport. In particular, all possible attempts should be made to ensure that the costs of aviation fully include the environmental and social costs, in accordance with the “polluter pays” principle.
The Government should also acknowledge the fact that the tax free status of aviation fuel effectively acts as a subsidy for the aviation industry, and should therefore fully factor this into its economic analysis of the costs and impacts of the industry.