Transport presents many difficulties for policy makers seeking better air quality. Rob Bell reports on the findings of the latest European Environment Agency report assessing the environmental impact of transport across Europe.

The demand for ease of movement around towns and cities, as well as further afield, is central to the lifestyle of UK citizens and the economy. The Government has taken certain measures to encourage people out of their cars and onto greener forms of transportation such as buses and trains; vehicle manufacturers have been set binding targets for production of less-polluting cars, vans and trucks; and some local administrations have introduced low emission zones (LEZ) and other restrictions on more polluting vehicles.

However, vehicles remain responsible for damaging levels of air pollutant emissions, the cause of one quarter of Europe’s greenhouse gas (GHG) emissions. The European Environment Agency (EEA) says many of the environmental problems that result from our transport systems can be addressed by stepping up efforts to meet new EU targets.

Recent improvements in air

The EEA’s annual report under the Transport and Environment Reporting Mechanism (TERM) assesses the environmental impact of transport across Europe, concluding that there have been some improvements over recent years, although they can be partly attributed to the fall in economic activity during the recession.

But as EU Member State economies recover, leading to increased movement of goods, work-related commuting and more recreational travel, the fall in transport’s environmental impacts will slow. The EEA says EU transport targets must therefore focus efforts to further reduce environmental impacts.

The report says: “Between 2009 and 2010, all air pollutant emissions from transport except nitrogen oxide (NOx) decreased by between 2.5% and 10%. In the period from 1990 to 2010, emissions of the main pollutants contributing to acidification, particulate matter (PM) and ozone (O3) formation decreased in the EEA-32 [the 32 EEA Member States, made up of the 27 EU Member States, Iceland, Liechtenstein, Norway, Switzerland and Turkey].

“But, in spite of these reductions in pollutant emissions, road transport continues to significantly affect urban air quality, and many cities continue to face air quality problems. In 2010, the nitrogen dioxide (NO2) annual limit value was exceeded at 44% of Europe's urban traffic stations, while it was exceeded at 4% of the urban background stations and only at very few rural background stations. Meanwhile, the percentage of traffic locations that have recorded an excess of the daily limit value for PM with a diameter of 10 micrometers or less (PM10) increased in 2010 compared to 2009.”

The EEA says that although air pollution has decreased over the last two decades, it is still a major problem in many areas. Some policies put in place with the aim of addressing this problem have proven to be only partially successful, with the Euro standards for vehicles not succeeding in reducing real NO2 emissions to the levels set out in the legislation, although the EEA’s report says they have made substantial improvements to air quality overall.

Increasing transport of goods is leading to poor air quality, the report says, with freight one of the main causes of high levels of NO2. Increased shipping over the last two decades has also meant emissions of acid rain-causing sulphur oxides have only decreased by 14% since 1990, despite major efficiency improvements by the sector.

The EEA’s Executive Director, Jacqueline McGlade, says: “One of the big challenges of the 21st century will be to mitigate the negative effects of transport — greenhouse gases, air pollution and noise — while ensuring positive aspects of mobility. Europe can take the lead by intensifying its work in the area of technological innovation in electric mobility. Such change could transform inner city living.”

Reducing transport energy consumption

Europe also needs to further reduce the energy consumed by transport, the EEA says, as there has only been a 4.3% fall in 2011 from its peak in 2007. The report points out that energy use in some transport modes has been strongly influenced by economic fluctuations in recent years, with freight transport demand particularly sensitive.

The report says that after a sharp drop between 2008 and 2009, freight transport grew in 2010. “Freight transport demand is still highly sensitive to changes in gross domestic product (GDP). Demand for freight transport increased by 5.4% in 2010, a faster rate than the increase in European Union GDP. At the same time, passenger demand fell slightly. Recent increases in the fuel price have not significantly affected transport demand.”

Passenger transport demand fell almost 1% between 2009 and 2010. The report says: “This seems to go against the long-term trend, as passenger transport demand has increased steadily across the EU since records began in the mid-1990s. Private car use has stayed more or less steady, despite the economic downturn and wide fuel price fluctuations over the last decade.

“In some cases, prices may be influencing people to make choices that are damaging for the environment. Buying a car has become steadily cheaper in real terms since the mid-1990s, while train travel and passenger transport by water has become more expensive.”

Nonetheless, new cars are becoming more fuel efficient, with the average car sold in 2011 now 3.3% more efficient than the average sold the year before.

The transport sector has to reduce carbon dioxide (CO2) emissions by 68% between 2010 and mid-century in order to meet the EU target. GHG emissions from transport fell by 0.4% between 2009 and 2010, and early estimates show a similar decrease between 2010 and 2011.

Noise

Noise is another impact from transport that has the potential to cause health problems. The report finds that in Europe’s biggest cities, three of every five residents are exposed to harmful levels of traffic noise. Even in the countryside, 24 million Europeans are exposed to damaging traffic noise at night. The EEA says this can cause both physical and psychological problems.

The report says: “Noise from road transport affects many people. In the largest European cities (with populations of more than 250,000) almost 70 million people, or more than 62% of the population of the cities analysed, are exposed to long-term average road traffic noise levels exceeding the EU threshold for excess exposure, which uses a weighted average noise during the day, evening and night.

“At night, more than 48 million people in the same urban areas are exposed to long-term average road noise levels higher than the EU threshold for excess exposure at night time.”

Interestingly, the problem of traffic noise, and the negative health impacts EU citizens suffer as a result, will be reduced alongside action to make vehicles that are less damaging in terms of air quality and climate change.

Environmental group Transport & Environment (T&E) says research it commissioned from research organisation TNO has confirmed that measures aimed at improving fuel efficiency also reduce vehicle noise.

T&E’s report, Road Vehicle Noise Versus Fuel Consumption and Pollutant Emissions, shows developments in engine technology that improve fuel economy — thus cutting GHG emissions — will also reduce noise. T&E says: “One example is the use of smaller engines with turbochargers, as smaller engines are quieter and a turbo reduces noise still further.”

Another study carried out by TNO states that there are financial benefits from reducing the noise levels of cars. T&E says: “This counters suggestions from the car industry, notably Porsche, that towns and cities need to be designed differently to better assimilate traffic noise.”

Tentative progress

While it is clear that improvements in air quality have been limited and a number of major problems remain, the EEA report’s principal finding is that “Europe is making tentative progress in reducing the impacts from transport”.

There have been two main developments leading to this conclusion. The report says: “First, Europe now has specific quantitative targets for reducing impacts from transport. These targets were mostly agreed in 2011 and include a target to cut GHG emissions from transport by 60% by 2050 compared with 1990 levels. The establishment of agreed targets is in itself a step in the right direction towards reducing the impacts of transport.

“Second, some of the recent data have shown reductions in emissions from transport and improvements in efficiency.”

However, the EEA makes clear there are several important caveats to what it describes as a “broadly positive picture”. First, for a number of the EU’s targets the methodology for measuring progress has yet to be finalised, or datasets are not yet fully complete. A second caveat is that for many targets, the base year against which current data are compared is still relatively recent, which the EEA says makes it difficult to read any meaningful trend into a dataset of only a few years.

The report says: “GHG emissions from transport (including aviation but excluding international maritime) are falling, as are emissions from international maritime transport. However, many of these improvements can be attributed to the economic downturn. They may therefore not point to long-term improvements.”

This issue leads the EEA to make an important point — that although the EU is generally moving in line with the “target path” toward the 60% emissions cut its targets demand, this does not mean transport-related impacts are on a continued and uniform downward trend every year. The report says: “Transport energy consumption actually rose slightly in 2011 compared with 2010 (by 0.1%), while overall transport GHG emissions (including aviation but excluding international maritime) in 2010 only reduced by 0.4% compared to 2009.”

Worryingly, the EEA says “many targets are not moving in the right direction at all”. According to the report: “While there have been improvements in average CO2 tailpipe emissions from new passenger cars, there has not been enough progress on the consumption of oil in transport or on meeting the related goal of sourcing 10% of transport fuel from renewable sources.”

The report continues: “The proportion of alternatively fuelled vehicles has increased to just over 4% of all vehicles in 2010 (based on selected EEA member countries). In 2010 and 2011, sales of electric vehicles increased significantly (from less than 200 vehicles to almost 9000 in the EU-27), while those of LPG [liquefied petroleum gas] and CNG [compressed natural gas] declined sharply.”

Progress towards targets on transport oil consumption and a 10% share of renewable energy in the transport sector for each Member State are “modest”, the EEA says, and not currently sufficient that the desired levels, when compared with “target path” values for 2010, will be achieved.

The report says: “A range of alternative fuels are required in the market, including electricity, hydrogen biofuels, methane (compressed natural gas (CNG) and biomethane), LPG and others.

“However, market penetration depends on the availability of appropriate infrastructure, which should be in line with technology developments and market penetration rates of vehicles powered by alternative fuels. Appropriate support at the Member State and EU level is required to increase uptake of alternative fuels (for example, fiscal incentives for consumers, provision of infrastructure, etc), as well as ensuring potential consumers are able to compare alternatively fuelled vehicles with conventional vehicles.”

Policy measures not always measuring up

The report also points out that the policy measures put in place by the EU have not always had the desired impact. The report says: “The EU has introduced and implemented various legal instruments in order to achieve levels of air quality that do not adversely impact human health and the environment. As a result of these policies, air pollutant emissions in Europe have decreased considerably over the past decades, resulting in improved air quality.

“However, due to complex links between emissions and air quality, as well as a number of uncertainties associated with emission estimates, reductions have not always produced a corresponding decline in ground level concentrations of air pollutants. For example, the decrease in NOx transport emissions (which fell by 27% between 2001 and 2010 in the EU) is considerably greater than the fall in NO2 annual mean concentrations (which fell by approximately 8% measured at stations close to traffic, between 2001 and 2010).

“This can be attributed to the fact that emission standards for diesel vehicles have not delivered the improvements anticipated under real-world conditions (including the increased proportion of NOx emitted directly as NO2 from the exhaust of more modern diesel vehicles).”

The challenge ahead

Overall, it appears transport will remain one of the biggest challenges facing policy makers at both Member State and EU level for years to come. With economies and the public’s lifestyles dependent on road freight and private cars, only so much can be achieved through, for example, forcing manufacturers to produce cars with lower emissions.

That said, there is a broad suite of policies in place aimed at addressing transport’s environmental impacts. The Government needs to work towards compliance with these European targets. With local actions such as the implementation of LEZs, and, as Jacqueline McGlade says, further innovation in the arena of electric cars, along with action to encourage take-up, further progress towards clean air in UK cities can be achieved.

Further information

  • The Contribution of Transport to Air Quality – TERM 2012: Transport Indicators Tracking Progress Towards Environmental Targets in Europe (EEA report)

  • Road Vehicle Noise Versus Fuel Consumption and Pollutant Emissions (T&E report)

Last reviewed 26 February 2013