next
previous
items

Indicator Assessment

Specific air pollutant emissions

Indicator Assessment
Prod-ID: IND-109-en
  Also known as: TERM 028
Published 21 Apr 2009 Last modified 11 May 2021
7 min read
This is an old version, kept for reference only.

Go to latest version
Topics:
This page was archived on 22 Feb 2017 with reason: No more updates will be done

The specific emissions of air pollutants from passenger and freight transport decreased during the time period 1995-2007 for the majority of transport modes and especially for passenger transport. The highest reduction of specific emissions can be observed in the road sector, following the implementation of increasingly strict emission standards. Railway and aviation have also recorded reductions, while maritime passenger and freight transport emissions remained approximately constant over the same time period. Rail and water transport are still relatively clean forms of transport - compared to road and air transport - but without any regulations on their emissions, these modes might lose this leading position.

TERM28 Modelled specific emissions of NOx per passenger-km or tonne-km and per mode of transport

Note: TREMOVE results refer to 30 EEA member countries (that is EU-27 plus Norway, Switzerland, Turkey) and Croatia, while TRENDS covers only EU-15.

Data source:

TERMOVE and TRENDS

TERM28 Modelled specific emissions of VOC per passenger-km or tonne-km and per mode of transport

Note: TREMOVE results refer to 30 EEA member countries (that is EU-27 plus Norway, Switzerland, Turkey) and Croatia, while TRENDS covers only EU-15.

Data source:

TERMOVE and TRENDS

TERM28 Modelled specific emissions of PM per passenger-km or tonne-km and per mode of transport

Note: TREMOVE results refer to 30 EEA member countries (that is EU-27 plus Norway, Switzerland, Turkey) and Croatia, while TRENDS covers only EU-15.

Data source:

TERMOVE and TRENDS

TERM28 Modelled specific emissions of CO per passenger-km or tonne-km and per mode of transport

Note: TREMOVE results refer to 30 EEA member countries (that is EU-27 plus Norway, Switzerland, Turkey) and Croatia, while TRENDS covers only EU-15.

Data source:

TERMOVE and TRENDS

  • Road remains by far the most polluting passenger transport mode with respect to CO and VOC specific emissions, even though it recorded the highest decreases (69 and 44 % for CO and VOC emissions respectively) from 1995 to 2007 compared to the other modes. As regards NOx specific emissions, road passenger transport emits about the same as air transport and about one third and one fourth of the specific emissions from maritime and rail transport respectively. Road is also the most polluting freight transport mode for all pollutants (with the exception of PM), although the specific emissions decreased from 35 to 64 % over the same period.
  • Rail is the generally the cleanest mode of transport for most pollutants. Specific NOx and PM emissions of rail transport have decreased considerably from 1995 to 2007, mainly due to the trend towards electric powered trains, especially for passenger traffic. Specific emissions from trains depend critically on the technical level and the method of energy production used. The emission factors for electricity production represent the airborne pollutants incurred during the whole production and supply process from fuel extraction to electricity transport to the sub-stations feeding the railway network. This indicates that the focus in the future should be in controlling emissions from power generation, along with implementing the engine economy and emission control technology, which has already advanced.
  • Maritime shipping is the cleanest mode of freight transport, except for PM and specific sulphur oxide (SOx) emissions, which are the highest for shipping (and aviation), mainly due to the high sulphur content of bunker fuels. However, maritime shipping remains the most polluting passenger transport mode with regard to the specific NOx and PM emissions. The emissions generated by the maritime fleet are largely dependent on the quantity of fuel consumed; however, there are several factors besides fuel consumption, which influence the emissions generated. These include the fuel quality and the engine type. In particular, SOx and PM emissions are influenced by the quantity of sulphur within the fuel. In the future, emission reductions are expected from waterborne transport, mainly as a result of improved fuel quality and engine technology. EU legislation setting more stringent limits for sulphur content in fuel oils will greatly contribute to the expected emission reductions. To this end, the European Commission proposed 'A European Union strategy to reduce atmospheric emissions from seagoing ships'.
  • It should be noted that the significant reductions in the emissions of all pollutants from road transport are mainly attributed to technological improvements and policy measures resulting from the strict emission standards imposed. On the other hand, the emissions from the other modes of transport are not subject to any emission control regulations, which would result in emission reductions similar to those from road transport.

Supporting information

Indicator definition

  • Specific emissions are defined as emissions of pollutants per transport unit (passenger-km or tonne-km), specified by mode (road, rail, inland, maritime, air). The pollutants considered include NOx, VOC, PM and CO.
  • For passenger transport, specific emissions are expressed in grams of pollutant (NOx, VOC, PM, CO) per passenger-kilometre. For freight transport, specific emissions are expressed in grams of pollutant (NOx, VOC, PM, CO) per tonne-kilometre.

Units

For passenger transport, specific emissions are expressed in grams of pollutant (NOx, VOC, PM, CO) per passenger-kilometer.

For freight transport, specific emissions are expressed in grams of pollutant (NOx, VOC, PM, CO) per tonne-kilometer.


 

Policy context and targets

Context description

Since specific emissions are expressed per transport unit, occupancy rates and load factors have a considerable effect on specific emissions produced from passenger and freight transport respectively. Reduction of specific emissions can be achieved by increasing occupancy rates and load factors and/or by decreasing the emissions per vehicle-km (e.g. by setting stricter emission standards and introducing more energy efficient technologies such as hybrid, plug-in hybrids, electric vehicles, etc).

Targets

No explicit targets exist at European level directly addressing specific emissions. Policy objectives are rather set with respect to the environmental performance of the fleet (see also TERM 34). 

Related policy documents

No related policy documents have been specified

 

Methodology

Methodology for indicator calculation

For passenger transport, the specific emissions are calculated by dividing the pollutant emissions of each mode (i.e. road, rail, maritime and air transport) by the respective passenger-kilometres.
For freight transport, the specific emissions are calculated by dividing the pollutant emissions of each mode (i.e. road, rail, inland shipping and maritime transport) by the respective tonne-kilometres.

The pollutant emissions for the remaining modes of transport (i.e. rail, inland shipping, maritime and air transport) are calculated using Tier 1 emission factors from the EMEP/EEA air pollutant emission inventory guidebook.

Activity data for inland shipping rail and maritime transport are extracted from PRIMES, Eurostat.

For air transport, the number of total LTOs (from EUROSTAT-avia_tf_aca) is used to calculate the pollutant emissions.

For the calculation of emissions from electric trains, the relevant emission factor from electricity generation (in grams of pollutant per kWh of energy produced) was used. To this aim, the total emissions of each pollutant (data from the EU submission to CLRTAP), were divided by the total electricity production in the European Union (data from EUROSTAT).

Methodology for gap filling

Passenger- and tonne-kilometres and emissions of NOx, VOC, PM and CO are modelled and therefore no gap filling is necessary. 

Methodology references

 

Uncertainties

Methodology uncertainty

COPERT 4 is used for road transport emissions calculations in EC4MACS, whereas the Tier 1 method of the EMEP/EEA air pollutant emission inventory guidebook is used for non-road transport modes.

 

    Data sets uncertainty

    Since the data on pollutant emissions, passenger-km and tonne-km are modelled rather than measured, the data must be treated as estimates. The uncertainty of emissions and the uncertainty of passenger-km and tonne-km vary significantly among different countries depending on the underlying statistical data used for each country

    Rationale uncertainty

    No uncertainty has been specified

    Data sources

    Other info

    DPSIR: Pressure
    Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
    Indicator codes
    • TERM 028
    Frequency of updates
    Updates are scheduled once per year
    EEA Contact Info info@eea.europa.eu

    Permalinks

    Geographic coverage

    Dates

    Topics

    Topics:

    Tags

    Filed under:
    Filed under: transport
    Document Actions