Indicator Assessment

Ammonia (NH3) emissions

Indicator Assessment
Prod-ID: IND-168-en
  Also known as: APE 003
Published 20 Dec 2012 Last modified 11 May 2021
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This is an old version, kept for reference only.

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This page was archived on 18 Jun 2015 with reason: Other (Discontinued Indicator)
    • EEA-32 emissions of NH3 have declined by 28% between the years 1990 and 2010. Agriculture was responsible for 94% of NH3 emissions in 2010.
    • The reduction in emissions within the agricultural sector is primarily due to a reduction in livestock numbers (especially cattle) since 1990, changes in the handling and management of organic manures and from the decreased use of nitrogenous fertilisers. The reductions achieved in the agricultural sector have been marginally offset by the increase in annual emissions over this period in the road-transport sector, and to a lesser extent the 'Solvent and product use' and 'Non-road transport' sectors.
    • All but two of the EU-27 Member States reported 2010 national NH3 emissions under NECD below the level of the 2010 emission ceilings set in the National Emission Ceilings Directive (NECD)[1]. Emissions in 2010 for two of the three non-EU countries having emission ceilings set under the UNECE/CLRTAP Gothenburg protocol (Liechtenstein, Norway and Switzerland) were also below the level of the respective 2010 ceilings.
    • Environmental context: NH3 contributes to acid deposition and eutrophication. The subsequent impacts of acid deposition can be significant, including adverse effects on aquatic ecosystems in rivers and lakes and damage to forests, crops and other vegetation. Eutrophication can lead to severe reductions in water quality with subsequent impacts including decreased biodiversity, changes in species composition and dominance, and toxicity effects. NH3 also contributes to the formation of secondary particulate aerosols, an important air pollutant due to its adverse impacts on human health.

[1] Emissions data reported by EU member states under NECD is used for comparison with NECD ceilings, and data reported under CLRTAP is used for all other calculations unless otherwise stated. 2010 emissions reported under NECD in 2012 by 11 member states differed from that reported under CLRTAP.

This indicator is discontinued. No more assessments will be produced.

Change in ammonia (NH3) emissions compared with the 2010 NECD and Gothenburg protocol targets (EEA member countries)

Note: The reported change in ammonia (NH3) emissions for each country, 1990-2010 in comparison with the 2010 NECD and 2020 Gothenburg protocol targets.

Distance-to-target for EEA member countries

Note: The distance-to-target indicator shows how current NH3 emissions compare to a linear emission reduction 'target-path' between 2010 emission levels and 2020 Gothenburg emission ceilings for each country. Negative percentage values indicate the current emissions in a country are below the linear target path; positive values show that current emission lie above a linear target path to 2020.

EEA-32 ammonia emissions have decreased by 28% between 1990 and 2010.

In general, the 27 EU Member States have made excellent progress in reducing emissions of ammonia, and 25 reported 2010 emissions under NECD which were below the level of their respective 2010 emission ceilings. The remaining countries, Finland and Spain, require further reductions in emissions of 17% and 5% respectively in order to meet their continuing obligation under the NECD. As indicated in Fig. 2, Denmark reported 2010 emissions under CLRTAP which were above the level of their NECD ceiling, however emissions reported under NECD were lower than their 2010 ceiling.

Finland reported emissions for 2010 which were significantly higher than their NECD ceiling and, although emissions reported under CLRTAP reduced by 6% between 1990 and 2000, their emissions have remained largely stable since 2000. Conversely, ammonia emissions in Spain have risen by around 17% since 1990, although a reduction equivalent to 3% of 1990 emissions has been reported from 2000 to 2010.

Iceland, Lichtenstein, Norway, Switzerland and Turkey are not members of the European Union and hence have no emission ceilings set under the NECD. Norway and Switzerland have ratified the UNECE LRTAP Convention's Gothenburg Protocol, requiring them to reduce their emissions to the agreed ceiling specified in the protocol by 2010. Liechtenstein has also signed, but not ratified the protocol. Whilst Norway and Switzerland reported 2010 emissions below the level of their 2010 ceiling under the Gothenburg Protocol, emissions in Lichtenstein were above the level of their 2010 ceiling having risen significantly between 2000 and 2009, however a 9% reduction in emissions was reported between 2009 and 2010.

The NECD protocol is currently being reviewed, as part of the implementation of the Thematic Strategy on Air Pollution, but a proposal for a revised directive is presently on hold until 2013. A revision of the Gothenburg protocol was published in June 2012, and proposed percentage emission reductions from 2005 levels to be met by 2020 for the four already regulated substances (NOX, NMVOC, SO2 and NH3) and in addition for primary emissions of PM2.5. Existing emission ceilings for 2010 have been extended to 2020 such that all countries have additional obligations to maintain emission levels below their 2010 ceilings, or to further reduce emissions if they have not yet met these ceilings.

Ten of the EU-27 Member States have already met the 2020 targets proposed under the Gothenburg protocol, and all except eight of the remaining countries are on track to reduce emissions to their ceiling by or before 2020. Of these countries however, only Latvia reported 2010 emissions which were more than 10% of their 2005 total over the linear target path to their 2020 target.

Sector share of ammonia emissions (EEA member countries)

Note: The contribution made by different sectors to emissions of ammonia in 2010.

Change in ammonia emissions for each sector between 1990 and 2010 (EEA member countries)

Note: Percentage change in ammonia (NH3) emissions for each sector between 1990 and 2010.

Contribution to total change in ammonia (NH3) emissions for each sector (EEA member countries)

Note: The contribution made by each sector to the total change in ammonia (NH3) emissions between 1990 and 2010.

The agricultural sector remains the major source of NH3 emissions; despite emissions falling by 29% since 1990, agriculture contributed 95% of total emissions in 1990, and 94% in 2010.

These emissions derive mainly from the decomposition of urea in animal wastes and uric acid in poultry wastes. Emissions depend on the animal species, age, weight, diet, housing systems, waste management and storage techniques. The majority of the reduction in emissions is due to the combination of reduced livestock numbers across Europe (especially cattle), and the lower use of nitrogenous fertilisers. NH3 emissions have also declined in EEA-32 countries outside the European Union between 1990 and 2010. Again this is primarily due to reductions which have occurred in the agricultural sector as a result of decreasing animal numbers.

Emissions from road transport, though relatively small, have risen from 1990 levels as a result of the increasing use of three-way catalytic converters in the vehicle fleet; these release NH3 as a result of an unwanted reaction involving hydrogen which reduces NO to NH3. However emissions have fallen since 2000, and are projected to fall in the future as the second generation of catalysts, which emit lower levels of NH3 than the first generation catalysts, penetrate the vehicle fleet.

Supporting information

Indicator definition

  • This indicator tracks trends since 1990 in anthropogenic emissions of sulphur dioxide.
  • The indicator also provides information on emissions by sectors: energy production and distribution; energy use in industry; industrial processes; road transport; non-road transport; commercial, institutional and households; solvent and product use; agriculture; waste; other.
  • Geographical coverage: EEA-32. The EEA-32 country grouping includes countries of the EU-27 (Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, and the United Kingdom) EFTA-4 (Iceland, Liechtenstein, Switzerland and Norway) and Turkey.
  • Temporal coverage: 1990-2010


ktonnes (1000 tonnes)


Policy context and targets

Context description

A number of policies have been implemented within Europe that either directly or indirectly act to reduce emissions of NH3. These include:

  • The National Emission Ceilings Directive 2001/81/EC (NECD) which entered into force in the European Community in 2001. The NECD sets emission ceilings for four important air pollutants (NH3, sulphur dioxide (SO2), nitrogen oxides (NOX) and non-methane volatile organic compounds (NMVOCs)) to be achieved from 2010 onwards for each Member State. The ceilings are designed to improve the protection in the Community of the environment and human health against risks of adverse effects arising from acidification, eutrophication and ground level ozone. The NECD is presently under review, the European Commission may adopt a proposal for a revised Directive during 2010.
  • The Gothenburg Protocol (1999) to the United Nations Economic Commission for Europe's (UNECE) Convention on Long-Range Transboundary Air Pollution (LRTAP Convention) to abate acidification, eutrophication and ground-level ozone. A key objective of the protocol is to regulate emissions on a regional basis within Europe and to protect eco-systems from transboundary pollution by setting emission reduction ceilings to be reached by 2010 for the same four pollutants as addressed in the NECD (i.e. NH3, SOX, NOX, and NMVOCs). Overall for the EU Member States, the ceilings set within the Gothenburg protocol are generally either slightly less strict or the same as the emission ceilings specified in the NECD.
  • The Directive on Integrated Pollution Prevention and Control (96/61/EC) entered into force in 1999.  It aims to prevent or minimise pollution to air, water or land from various industrial sources throughout the European Union. Those installations covered by Annex I of the IPPC Directive are required to obtain authorisation from the authorities to operate. New installations and existing installations, which are subject to 'substantial changes' have been required to meet the requirements of the IPPC Directive since 30th October 1999. Other existing installations must have been brought into compliance by the 30 October 2007. The emission limit values outlined in the permit conditions must be based on best available techniques (BAT). The Commission has been undertaking a review of the IPPC Directive and related legislation on industrial emissions and on the 21 December 2007 adopted a proposal for a Directive on industrial emissions. The proposal recasts seven existing Directives relating to industrial emissions (including IPPC and the Large Combustion Plant Directive (2001/80/EC) into a single legislative instrument.

Apart from the NECD and Gothenburg Protocol and the IPPC Directive, there is currently no other EU legislation proposed or in force specifically aimed at reducing ammonia emissions. However, several regulatory instruments have influenced EU emissions of ammonia from the agriculture sector since 1990, such as:

  • the Common Agricultural Policy (CAP);
  • the Nitrate Directive (91/676/EEC);
  • the Water Framework Directive (2000/60/EC).

These measures have had the indirect effect of changing agricultural practices across the EU, and have, for instance, led to a reduced use of nitrogenous fertilisers and to an overall decrease in cattle numbers, both of which affect the levels of ammonia emissions. The reforms of CAP, and specifically the removal of the link between farm production and payments, has also resulted in reduced livestock numbers across the EU-15 and hence also will have indirectly contributed to the decrease in ammonia emissions observed.


Emissions of NH3 are covered by the EU National Emission Ceilings Directive (NECD) (2001/81/EC) and the Gothenburg protocol under the United Nations Convention on Long-Range Transboundary Air Pollution (LRTAP Convention) (UNECE 1999). The NECD generally involves slightly stricter emission reduction targets than the Gothenburg Protocol for EU-15 countries for the period 1990-2010. The Gothenburg Protocol entered into force on 17 May 2005, after ratification by 16 countries early in 2005.The 2012 revision to the Gothenburg protocol proposed emission reduction targets for 2020 relative to 2005 reported emissions for all EU-27 member states, and some EEA-32 non-EU member states.

Table: 2010 NH3 ceilings under the NEC Directive and the Gothenburg Protocol (kt)


2010 NECD

2010 CLRTAP Gothenburg Protocol ceilings

2020 CLRTAP Gothenburg Protocol ceilings

Austria 66 66 62
Belgium 74 74 70
Bulgaria 108 108 56
Cyprus 9 N/A 5
Czech Republic 80 101 64
Denmark 69 69 63
Estonia 29 N/A 10
Finland 31 31 31
France 780 780 634
Germany 550 550 545
Greece 73 73 63
Hungary 90 90 72
Iceland* N/A N/A N/A
Ireland 116 116 108
Italy 419 419 395
Latvia 44 44 15
Liechtenstein N/A 0.15 N/A
Lithuania 84 84 35
Luxembourg 7 7 5
Malta 3 N/A 2
Netherlands 128 128 122
Norway N/A 23 21
Poland 468 468 267
Portugal 90 108 47
Romania 210 210 173
Slovakia 39 39 24
Slovenia 20 20 17
Spain 353 353 357
Switzerland N/A 63 59
Sweden 57 57 47
Turkey* N/A N/A N/A
United Kingdom 297 297 283

* Iceland and Turkey do not have a ceiling under either the NEC Directive or the Gothenburg protocol.

Related policy documents



Methodology for indicator calculation


This indicator is based on officially reported national total and sectoral emissions to EEA and UNECE/EMEP (United Nations Economic Commission for Europe/Cooperative programme for monitoring and evaluation of the long-range transmission of air pollutants in Europe) Convention on Long-range Transboundary Air Pollution (LRTAP Convention), submission 2011. For the EU-27 Member States, the data used is consistent with the emissions data reported by the EU in its annual submission to the LRTAP Convention.

Recommended methodologies for emission inventory estimation are compiled in the EMEP/EEA Air Pollutant Emission Inventory Guidebook, (EMEP/EEA, 2009). Base data are available from the EEA Data Service ( and the EMEP web site ( Where necessary, gaps in reported data are filled by the European Topic Centre/EEA using simple interpolation techniques (see below). The final gap-filled data used in this indicator is available from the EEA Data Service (

Base data, reported in the UNECE/EMEP Nomenclature for Reporting (NFR) sector format, is aggregated into the following EEA sector codes to obtain a consistent reporting format across all countries and pollutants:

  • Energy production and distribution: emissions from public heat and electricity generation, oil refining, production of solid fuels, extraction and distribution of solid fossil fuels and geothermal energy;
  • Energy use in industry: emissions from combustion processes used in the manufacturing industry including boilers, gas turbines and stationary engines;
  • Industrial processes: emissions derived from non-combustion related processes such as the production of minerals, chemicals and metal production;
  • Road transport: light and heavy duty vehicles, passenger cars and motorcycles;
  • Non-road transport: railways, domestic shipping, certain aircraft movements, and non-road mobile machinery used in agriculture & forestry;
  • Commercial, institutional and households: emissions principally occurring from fuel combustion in the services and household sectors;
  • Solvent and product use: non-combustion related emissions mainly in the services and households sectors including activities such as paint application, dry-cleaning and other use of solvents;
  • Agriculture: manure management, fertiliser application, field-burning of agricultural wastes
  • Waste: incineration, waste-water management;
  • Other: emissions included in national total for entire territory not allocated to any other sector


The following table shows the conversion of Nomenclature for Reporting (NFR) sector codes used for reporting by countries into EEA sector codes:

EEA classification

Non-GHGs (NFR)


National totals

National total


Energy production and distribution

1A1, 1A3e, 1B


Energy use in industry



Road Transport



Non-road transport (non-road mobile machinery)

1A3 (excl. 1A3b)


Industrial processes



Solvent and product use









Commercial, institutional and households

1A4ai, 1A4aii, 1A4bi, 1A4bii, 1A4ci, 1A4cii, 1A5a, 1A5b





Methodology for gap filling

An improved gap-filling methodology was implemented in 2010 that enables a complete time series trend for the main air pollutants (eg NOX, SOX, NMVOC, NH3 and CO) to be compiled. In cases where countries did not report emissions for any year, it meant that gap-filling could not be applied. For these pollutants, therefore, the aggregated data are not yet complete and are likely to underestimate true emissions. Further methodological details of the gap-filling procedure are provided in section 1.4.2 'Data gaps and gap-filling' of the European Union emission inventory report 1990–2009 under the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP).

Methodology references



Methodology uncertainty

The use of gap-filling for when countries have not reported emissions for one of more years can potentially lead to artificial trends, but it is considered unavoidable if a comprehensive and comparable set of emissions data for European countries is required for policy analysis purposes.

Data sets uncertainty

NH3 emission estimates in Europe are more uncertain than those for NOX, SO2 and NMVOCs due largely to the diverse nature of major agricultural sources. It is estimated that they are around ±30% (EMEP, 2009). The trend is likely to be more accurate than the individual absolute annual values - the annual values are not independent of each other.

Overall scoring: (1-3, 1=no major problems, 3=major reservations)

  • Relevancy: 1
  • Accuracy: 2
  • Comparability over time: 2
  • Comparability over space: 2


Rationale uncertainty

This indicator is regularly updated by EEA and is used in state of the environment assessments. The uncertainties related to methodology and data sets are therefore of importance. Any uncertainties involved in the calculation and in the data sets need to be accurately communicated in the assessment, to prevent erroneous messages influencing policy actions or processes.

Data sources

Other info

DPSIR: Pressure
Typology: Performance indicator (Type B - Does it matter?)
Indicator codes
  • APE 003
Frequency of updates
This indicator is discontinued. No more assessments will be produced.
EEA Contact Info


Geographic coverage

Temporal coverage


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