Reference metadata describe statistical concepts and methodologies used for the collection and generation of data. They provide information on data quality and, since they are strongly content-oriented, assist users in interpreting the data. Reference metadata, unlike structural metadata, can be decoupled from the data.
[4D1_E2] Eurostat - Environmental statistics and accounts; sustainable development
1.3. Contact name
Confidential because of GDPR
1.4. Contact person function
Confidential because of GDPR
1.5. Contact mail address
2920 Luxembourg, LUXEMBOURG
1.6. Contact email address
Confidential because of GDPR
1.7. Contact phone number
Confidential because of GDPR
1.8. Contact fax number
Confidential because of GDPR
2.1. Metadata last certified
9 February 2026
2.2. Metadata last posted
9 February 2026
2.3. Metadata last update
9 February 2026
3.1. Data description
This metadata refers to the dataset Air emissions accounts for greenhouse gases by NACE Rev. 2 activity - quarterly data.
This dataset reports greenhouse gases emissions into the atmosphere due to economic activities of resident units (businesses, families and government). Those emissions are measured according to the international System of Environmental-Economic Accounting (SEEA).
The greenhouse gases are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and fluorinated gases. Each greenhouse gas has a different capacity to cause global warming, depending on its radiative properties, molecular weight and the length of time it remains in the atmosphere. The global warming potential (GWP) of each gas is defined in relation to a given weight of carbon dioxide for a set time period (for the purpose of the Kyoto Protocol a period of 100 years). GWPs are used to convert emissions of greenhouse gases to a relative measure (known as carbon dioxide equivalents: CO2-equivalents). The weighting factors currently used are as defined in the IPCC Fifth Assessment Report: carbon dioxide = 1, methane = 28, nitrous oxide = 265 and sulphur hexafluoride = 23 500; hydrofluorocarbons and perfluorocarbons comprise a large number of different gases that have different GWPs.
The emissions are broken down by emitter categories related to the NACE Rev.2 classification of economic activities.
The quarterly estimates are modelled based on annual environmental accounting data, see 18.5 below.
3.2. Classification system
The dataset Air emissions accounts for greenhouse gases by NACE Rev. 2 activity - quarterly data [env_ac_aigg_q] has five dimensions:
Air pollutant (AIRPOL): Data are estimated for aggregated greenhouse gases (CO2, N2O in CO2 equivalent, CH4 in CO2 equivalent, HFC in CO2 equivalent, PFC in CO2 equivalent, SF6 in CO2 equivalent, NF3 in CO2 equivalent);
Geopolitical entity (GEO): European Union – 27 countries and EU Member States (for all the reference periods published);
Seasonal adjustment (S_ADJ): Unadjusted data (i.e. neither seasonally adjusted nor calendar adjusted data) and seasonally adjusted data (not calendar adjusted data) are presented;
Classification of economic activities - NACE rev.2 (NACE_R2): Data are published broken down by NACE classification of economic activities;
Unit (UNIT): The greenhouse gas emissions are measured in thousand tonnes of CO2 equivalents (THS_T), in tonnes per habitants (T_HAB), percentage change on previous period (PCH_PRE) as well as in percentage change compared to same period in previous year (PCH_SM);
Period of time (TIME): Quarterly data, starting from 2010Q1.
3.3. Coverage - sector
Greenhouse gases emitted by the entire national economy are covered, see also 3.7.
3.4. Statistical concepts and definitions
Air emissions accounts record the flows of residual gaseous emitted by resident units and flowing into the atmosphere.
Air emissions accounts record emissions arising from the activities of all resident units (=economic activities), regardless of where these emissions actually occur geographically. Air emissions accounts have the same system boundaries as the European System of Accounts and the System of Environmental-Economic Accounting, which are based on the same residence principle, see annex.
Natural flows of residual gaseous are excluded e.g. volcanos, forest fires. Also excluded are air emissions arising from land use, land use changes and forestry as well as any indirect emissions.
Greenhouse gas emissions are measured in thousand tonnes of CO2 equivalents.
3.6. Statistical population
The population is the national economy, i.e. the resident economic units and households as defined in SEEA CF 2012 and National Accounts (ESA).
3.7. Reference area
The reference area is the economic territory as defined in SEEA CF 2012 and National Accounts (ESA). A unit is said to be a resident unit of a country when it has a centre of economic interest in the economic territory of that country, that is, when it engages for an extended period (1 year or more) in economic activities in that territory.
By following this residence principle, the Air Emission Accounts record emissions from resident units' activities, regardless where they occur. This is the main conceptual difference to emission inventories for greenhouse gases (UNFCCC).
3.8. Coverage - Time
Data are quarterly. In NACE Rev. 2 breakdown complete time series are available since the first quarter of 2010.
3.9. Base period
Not applicable.
Data are presented in thousand tonnes of CO2 equivalents (THS_T), in tonnes per habitants (T_HAB), percentage change on previous period (PCH_PRE), as well as a percentage change compared to same period in previous year (PCH_SM). Quarterly data are available as seasonally non-adjusted and seasonally adjusted (not calendar adjusted).
The data refer to the quarters of the calendar year.
6.1. Institutional Mandate - legal acts and other agreements
Annual air emissions accounts are legally covered by Regulation (EC) No. 691/2011 on European environmental economic accounts. Member States produce annual estimates and transmit them to Eurostat 21 months after the end of the reference year. Eurostat publishes them after validation.
With a view to improve timeliness and frequency, Eurostat produces model-based quarterly estimates based on the annual accounts. For details on the estimation method, see 18.5 below.
The environmental economic accounts are fully in accordance with internationally agreed concepts and definitions set out in the system of environmental economic accounting 2012 – central framework (SEEA CF 2012, see annex). The SEEA CF is a multi-purpose conceptual framework to report the interactions between the environment and the economy.
6.2. Institutional Mandate - data sharing
Not applicable.
7.1. Confidentiality - policy
Regulation (EC) No 223/2009 on European statistics (recital 24 and Article 20(4)) of 11 March 2009 (OJ L 87, p. 164), stipulates the need to establish common principles and guidelines ensuring the confidentiality of data used for the production of European statistics and the access to those confidential data with due account for technical developments and the requirements of users in a democratic society.
7.2. Confidentiality - data treatment
In case there are confidential data, they are flagged "confidential" and not published.
8.1. Release calendar
Release dates are pre-announced in Eurostat’s release calendar.
8.2. Release calendar access
The release calendar is available at this website (Release calendar).
8.3. Release policy - user access
In line with the Community legal framework and the European Statistics Code of Practice Eurostat disseminates European statistics on Eurostat's website (see item 10 - 'Accessibility and clarity') respecting professional independence and in an objective, professional and transparent manner in which all users are treated equitably. The detailed arrangements are governed by the Eurostat protocol on impartial access to Eurostat data for users.
Data are disseminated simultaneously to all interested parties through a database update and on Eurostat's website.
The methodological note on quarterly GHG estimates is available in the Annex.
10.7. Quality management - documentation
Quality management is addressed in the methodological note in the Annex.
11.1. Quality assurance
The estimation model has been applied successfully over the years in other domains, e.g. quarterly national accounts. The estimation method is documented and transparent, see technical note in the Annex. The estimation error is monitored, see 11.2.
11.2. Quality management - assessment
The estimation error is monitored. This error is calculated as follows: the estimation method is simulated for the most recent reference year for which annual air emissions accounts are available. This simulated quarterly estimates are aggregated to annual data and compared with the actual available annual data. The error is reported in percentage points.
12.1. Relevance - User Needs
Air emissions are relevant for monitoring the interaction between the economy and the environment, in particular in a context of global climate change. Annual air emission accounts data are also used in modelling, including carbon footprint.
The relevance of air emission accounts is enhanced by using a conceptual framework consistent with National Accounts, which allows, e.g. to put in relation with estimates of production, value added, employment, GDP, etc.
The users include policy makers in environmental ministries, environmental organisations, students and interested citizens.
12.2. Relevance - User Satisfaction
There are no systematic studies of user satisfaction. Eurostat has regular hearings with European policymakers and contacts with the research community and other stakeholders to monitor the relevance of the statistics produced and identify new priorities.
12.3. Completeness
Data are complete, meaning they encompass all the sectors of the economy and the households.
13.1. Accuracy - overall
The overall accuracy is considered to be good.
13.2. Sampling error
Not applicable to statistical accounts.
13.3. Non-sampling error
Not applicable to statistical accounts.
14.1. Timeliness
Eurostat publishes the data 4.5 months after the reference period.
14.2. Punctuality
Release dates are pre-announced in Eurostat’s release calendar.
15.1. Comparability - geographical
Not applicable.
15.2. Comparability - over time
The comparability over time is good due to clear statistical concepts and definitions.
15.3. Coherence - cross domain
The data are coherent with principles, definitions and concepts in National Accounts (ESA - European System of Accounts) and Environmental Accounting (SEEA - System of Environmental-Economic Accounting).
Quarterly air emissions accounts are benchmarked to annual air emissions accounts, i.e. they are coherent by construction.
Air emissions accounts and physical energy flow accounts employ the same groupings of elementary economic units (NACE Rev. 2 activities) as the ESA supply and use tables. This coherence is important with regards to integrated analyses – e.g. applying Leontief-type input-output analysis.
15.4. Coherence - internal
The internal coherence is very high, ensured by the accounting framework.
The costs and burden to produce and release the data is about 14 person-days for Eurostat.
Every quarter Eurostat publishes the complete time series starting in 2010 Q1, which may lead to revisions of data previously published. Data are not revised in between quarterly releases, unless there are errors reported.
17.2. Data revision - practice
Reported errors are assessed for seriousness to determine whether they should trigger a correction of already disseminated data. Reported errors are corrected in the disseminated data as soon as the correct data have been validated.
18.1. Source data
The main data sources are annual air emissions accounts and a set of short-term predictors, see 18.5.
18.2. Frequency of data collection
Data are estimated quarterly.
18.3. Data collection
Annual air emissions accounts data are regulated by Regulation (EC) No. 691/2011 on European environmental economic accounts. The quarterly estimates are not based on a data collection but a model, based on the annual accounts.
18.4. Data validation
The quarterly estimates are validated with the annual data based on Regulation (EU) No 691/2011, which become available later.
18.5. Data compilation
The quarterly GHG estimates are modelled. For details see the methodological note in the Annex.
18.6. Adjustment
Seasonal adjustments are carried out by Eurostat. No weather nor calendar adjustment is performed.
Two main groups of seasonal adjustment methods can be distinguished: methods based on moving averages and model based methods (Handbook of Quarterly National Accounts, 7.29). Eurostat applies the X13 ARIMA-SEATS method, which is one of the most widely used methods. Seasonal adjustment is applied indirectly, i.e. Eurostat seasonally adjusts the predictor variables used for the temporal disaggregation. The exception is for quarterly estimates reported by EU Member States. In such cases, Eurostat applies the direct method and seasonally adjusts the quarterly air emission estimates which are reported.
Quarterly seasonally adjusted estimates for the EU are calculated based on the aggregation of quarterly figures for the individual Member States.
This metadata refers to the dataset Air emissions accounts for greenhouse gases by NACE Rev. 2 activity - quarterly data.
This dataset reports greenhouse gases emissions into the atmosphere due to economic activities of resident units (businesses, families and government). Those emissions are measured according to the international System of Environmental-Economic Accounting (SEEA).
The greenhouse gases are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and fluorinated gases. Each greenhouse gas has a different capacity to cause global warming, depending on its radiative properties, molecular weight and the length of time it remains in the atmosphere. The global warming potential (GWP) of each gas is defined in relation to a given weight of carbon dioxide for a set time period (for the purpose of the Kyoto Protocol a period of 100 years). GWPs are used to convert emissions of greenhouse gases to a relative measure (known as carbon dioxide equivalents: CO2-equivalents). The weighting factors currently used are as defined in the IPCC Fifth Assessment Report: carbon dioxide = 1, methane = 28, nitrous oxide = 265 and sulphur hexafluoride = 23 500; hydrofluorocarbons and perfluorocarbons comprise a large number of different gases that have different GWPs.
The emissions are broken down by emitter categories related to the NACE Rev.2 classification of economic activities.
The quarterly estimates are modelled based on annual environmental accounting data, see 18.5 below.
9 February 2026
Air emissions accounts record the flows of residual gaseous emitted by resident units and flowing into the atmosphere.
Air emissions accounts record emissions arising from the activities of all resident units (=economic activities), regardless of where these emissions actually occur geographically. Air emissions accounts have the same system boundaries as the European System of Accounts and the System of Environmental-Economic Accounting, which are based on the same residence principle, see annex.
Natural flows of residual gaseous are excluded e.g. volcanos, forest fires. Also excluded are air emissions arising from land use, land use changes and forestry as well as any indirect emissions.
Greenhouse gas emissions are measured in thousand tonnes of CO2 equivalents.
The population is the national economy, i.e. the resident economic units and households as defined in SEEA CF 2012 and National Accounts (ESA).
The reference area is the economic territory as defined in SEEA CF 2012 and National Accounts (ESA). A unit is said to be a resident unit of a country when it has a centre of economic interest in the economic territory of that country, that is, when it engages for an extended period (1 year or more) in economic activities in that territory.
By following this residence principle, the Air Emission Accounts record emissions from resident units' activities, regardless where they occur. This is the main conceptual difference to emission inventories for greenhouse gases (UNFCCC).
The data refer to the quarters of the calendar year.
The overall accuracy is considered to be good.
Data are presented in thousand tonnes of CO2 equivalents (THS_T), in tonnes per habitants (T_HAB), percentage change on previous period (PCH_PRE), as well as a percentage change compared to same period in previous year (PCH_SM). Quarterly data are available as seasonally non-adjusted and seasonally adjusted (not calendar adjusted).
The quarterly GHG estimates are modelled. For details see the methodological note in the Annex.
The main data sources are annual air emissions accounts and a set of short-term predictors, see 18.5.
Data are disseminated quarterly.
Eurostat publishes the data 4.5 months after the reference period.
Not applicable.
The comparability over time is good due to clear statistical concepts and definitions.
