Emission inventory

Last updated

An emission inventory (or emissions inventory [1] ) is an accounting of the amount of pollutants discharged into the atmosphere. An emission inventory usually contains the total emissions for one or more specific greenhouse gases or air pollutants, originating from all source categories in a certain geographical area and within a specified time span, usually a specific year.

Contents

An emission inventory is generally characterized by the following aspects:

Emission inventories are compiled for both scientific applications and for use in policy processes.

Use

Emissions and releases to the environment are the starting point of every environmental pollution problem. Information on emissions therefore is an absolute requirement in understanding environmental problems and in monitoring progress towards solving these. Emission inventories provide this type of information.

Emission inventories are developed for a variety of purposes:

Policy use

Two more or less independent types of emission reporting schemes have been developed:

Examples of the first are the annual emission inventories as reported to the United Nations Framework Convention on Climate Change (UNFCCC) [3] for greenhouse gases and to the UNECE Convention on Long-Range Transboundary Air Pollution (LRTAP) for air pollutants. In the United States, a national emissions inventory is published annually by the United States Environmental Protection Agency. This inventory is called the "National Emissions Inventory", and can be found here:

Examples of the second are the so-called Pollutant Release and Transfer Registers.

Policy users typically are interested in annual total emission only.[ citation needed ]

Scientific use

Air quality models need input to describe all air pollution sources in the study area. Air emission inventories provide this type of information. Depending on the spatial and temporal resolution of the models, the spatial and temporal resolution of the inventories frequently has to be increased beyond what is available from national emission inventories as reported to the international conventions and protocols.

Compilation

For each of the pollutants in the inventory emissions are typically estimated by multiplying the intensity of each relevant activity ('activity rate') in the geographical area and time span with a pollutant dependent proportionality constant ('emission factor').

Why: the source categories

To compile an emission inventory, all sources of the pollutants must be identified and quantified. Frequently used source categorisations are

Both source categorisations make a clear distinction between sources related to the combustion of (fossil) fuels and those that are not caused by combustion. In most cases the specific fuel combusted in the former is added to the source definition. Source categories include:

  1. Energy
    1. Fuel combustion
      1. Stationary combustion
        1. Industrial combustion
        2. Residential heating
      2. Mobile combustion (transport)
    2. Fugitive emissions from (fossil) fuel use
  2. Industrial Processes
  3. Solvent and other product use
  4. Agriculture
  5. LULUCF (Land Use, Land Use Change and Forestry)
  6. Waste

Many researchers and research projects use their own source classifications, sometimes based on either the IPCC or the SNAP source categories, but in most cases the source categories listed above will be included.

What: the pollutants

Emission inventories have been developed and still are being developed for two major groups of pollutants:

Where: geographical resolution

Typically national inventories provide data summed at the national territory only. In some cases additional information on major industrial stacks ('point sources') is available. Stacks are also called release points, because not all emissions come from stacks. Other industrial sources include fugitive emissions, which cannot be attributed to any single release point.

Some inventories are compiled from sub-national entities such as states and counties (in the U.S.), which can provide additional spatial resolution.

In scientific applications, where higher resolutions are needed, geographical information such as population densities, land use or other data can provide tools to disaggregate the national level emissions to the required resolution, matching the geographical resolution of the model.

When: temporal resolution

Similarly, national emission inventories provide total emissions in a specific year, based on national statistics. In some model applications higher temporal resolutions are needed, for instance when modelling air quality problems related to road transport. In such cases data on time dependent traffic intensities (rush hours, weekends and working days, summer and winter driving patterns, etc.) can be used to establish the required higher temporal resolution.

Inventories compiled from Continuous Emissions Monitors (CEMs) can provide hourly emissions data.

How: methodology to compile an emission inventory

The European Environment Agency updated in 2007 the third edition of the inventory guidebook. The guidebook is prepared by the UNECE/EMEP Task Force on Emission Inventories and Projections and provides a detailed guide to the atmospheric emissions inventory methodology. Especially for Road Transport the European Environment Agency finances COPERT 4, a software program to calculate emissions which will be included in official annual national inventories.

Quality

The quality of an emission inventory depends on its use. In policy applications, the inventory should comply with all what has been decided under the relevant convention. Both the UNFCCC and LRTAP conventions require an inventory to follow the quality criteria below (see [4] ):

CriterionDescription
Transparent:the assumptions and methodologies used for an inventory should be clearly explained to facilitate replication and assessment of the inventory by users of the reported information. The transparency of inventories is fundamental to the success of the process for the communication and consideration of information
Consistent:an inventory should be internally consistent in all its elements with inventories of other years. An inventory is consistent if the same methodologies are used for the base and all subsequent years and if consistent data sets are used to estimate emissions. Under certain circumstances referred to in the chapter on time series consistency (Time Series Consistency chapter of the General Guidance part of this Guidebook), an inventory using different methodologies for different years can be considered to be consistent if it has been recalculated in a transparent manner, taking into account any good practices
Comparable:estimates of emissions reported by Parties in inventories should be comparable among Parties. For this purpose, Parties should use the methodologies and formats agreed within the convention for estimating and reporting inventories
Complete:an inventory covers all sources, as well as all pollutants, included in the Convention and Protocols, as well as other existing relevant source categories which are specific to individual Parties, and therefore may not be included in the Guidebook. Completeness also means full geographic coverage of sources and sinks of a Party.
Accurate:a relative measure of the exactness of an emission estimate. Estimates should be accurate in the sense that they are systematically neither over or under true emissions, as far as can be judged, and that uncertainties are reduced as far as practicable. Appropriate methodologies conforming to guidance on good practices should be used to promote accuracy in inventories

A well constructed inventory should include enough documentation and other data to allow readers and users to understand the underlying assumptions and to assess its usability in an intended application.

See also

Notes

  1. US EPA, OAR (2015-03-11). "Air Emissions Inventories". www.epa.gov. Retrieved 2022-01-26.
  2. UNECE Arhus Convention
  3. Greenhouse gas emission inventories can be found at the UNFCCC website at
  4. Guidelines for the preparation of national communications by Parties included in Annex I to the Convention, Part I: UNFCCC reporting guidelines on annual inventories (following incorporation of the provisions of decision 13/CP.9)

Sources and further reading

Related Research Articles

<span class="mw-page-title-main">Kyoto Protocol</span> 1997 international treaty to reduce greenhouse gas emissions

The Kyoto Protocol (Japanese: 京都議定書, Hepburn: Kyōto Giteisho) was an international treaty which extended the 1992 United Nations Framework Convention on Climate Change (UNFCCC) that commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that global warming is occurring and that human-made CO2 emissions are driving it. The Kyoto Protocol was adopted in Kyoto, Japan, on 11 December 1997 and entered into force on 16 February 2005. There were 192 parties (Canada withdrew from the protocol, effective December 2012) to the Protocol in 2020.

The United Nations Framework Convention on Climate Change (UNFCCC) is the UN process for negotiating an agreement to limit dangerous climate change. Formally it is an international treaty among countries to combat "dangerous human interference with the climate system", in part by stabilizing greenhouse gas concentrations in the atmosphere. It was signed in 1992 by 154 states at the United Nations Conference on Environment and Development (UNCED), informally known as the Earth Summit, held in Rio de Janeiro. The treaty entered into force on 21 March 1994. "UNFCCC" is also the name of the Secretariat charged with supporting the operation of the convention, with offices on the UN Campus in Bonn, Germany.

<span class="mw-page-title-main">Exhaust gas</span> Gases emitted as a result of fuel reactions in combustion engines

Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline (petrol), diesel fuel, fuel oil, biodiesel blends, or coal. According to the type of engine, it is discharged into the atmosphere through an exhaust pipe, flue gas stack, or propelling nozzle. It often disperses downwind in a pattern called an exhaust plume.

<span class="mw-page-title-main">Emission intensity</span> Emission rate of a pollutant

An emission intensity is the emission rate of a given pollutant relative to the intensity of a specific activity, or an industrial production process; for example grams of carbon dioxide released per megajoule of energy produced, or the ratio of greenhouse gas emissions produced to gross domestic product (GDP). Emission intensities are used to derive estimates of air pollutant or greenhouse gas emissions based on the amount of fuel combusted, the number of animals in animal husbandry, on industrial production levels, distances traveled or similar activity data. Emission intensities may also be used to compare the environmental impact of different fuels or activities. In some case the related terms emission factor and carbon intensity are used interchangeably. The jargon used can be different, for different fields/industrial sectors; normally the term "carbon" excludes other pollutants, such as particulate emissions. One commonly used figure is carbon intensity per kilowatt-hour (CIPK), which is used to compare emissions from different sources of electrical power.

<span class="mw-page-title-main">Land use, land-use change, and forestry</span> Greenhouse gas inventory sector

Land use, land-use change, and forestry (LULUCF), also referred to as Forestry and other land use (FOLU) or Agriculture, Forestry and Other Land Use (AFOLU), is defined as a "greenhouse gas inventory sector that covers emissions and removals of greenhouse gases resulting from direct human-induced land use such as settlements and commercial uses, land-use change, and forestry activities."

Greenhouse gas inventories are emission inventories of greenhouse gas emissions that are developed for a variety of reasons. Scientists use inventories of natural and anthropogenic (human-caused) emissions as tools when developing atmospheric models. Policy makers use inventories to develop strategies and policies for emissions reductions and to track the progress of those policies.

<span class="mw-page-title-main">Greenhouse gas emissions</span> Sources and amounts of greenhouse gases emitted to the atmosphere from human activities

Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide, from burning fossil fuels such as coal, oil, and natural gas, is one of the most important factors in causing climate change. The largest emitters are China followed by the United States. The United States has higher emissions per capita. The main producers fueling the emissions globally are large oil and gas companies. Emissions from human activities have increased atmospheric carbon dioxide by about 50% over pre-industrial levels. The growing levels of emissions have varied, but have been consistent among all greenhouse gases. Emissions in the 2010s averaged 56 billion tons a year, higher than any decade before. Total cumulative emissions from 1870 to 2017 were 425±20 GtC from fossil fuels and industry, and 180±60 GtC from land use change. Land-use change, such as deforestation, caused about 31% of cumulative emissions over 1870–2017, coal 32%, oil 25%, and gas 10%.

A mobile emission reduction credit (MERC) is an emission reduction credit generated within the transportation sector. The term “mobile sources” refers to motor vehicles, engines, and equipment that move, or can be moved, from place to place. Mobile sources include vehicles that operate on roads and highways ("on-road" or "highway" vehicles), as well as nonroad vehicles, engines, and equipment. Examples of mobile sources are passenger cars, light trucks, large trucks, buses, motorcycles, earth-moving equipment, nonroad recreational vehicles (such as dirt bikes and snowmobiles), farm and construction equipment, cranes, lawn and garden power tools, marine engines, ships, railroad locomotives, and airplanes. In California, mobile sources account for about 60 percent of all ozone forming emissions and for over 90 percent of all carbon monoxide (CO) emissions from all sources.

The 1999 Gothenburg Protocol to Abate Acidification, Eutrophication and Ground-level Ozone is a multi-pollutant protocol designed to reduce acidification, eutrophication and ground-level ozone by setting emissions ceilings for sulphur dioxide, nitrogen oxides, volatile organic compounds and ammonia to be met by 2010. As of August 2014, the Protocol had been ratified by 26 parties, which includes 25 states and the European Union.

<span class="mw-page-title-main">Environmental effects of paper</span> Overview about the environmental effects of the paper production industry

The environmental effects of paper are significant, which has led to changes in industry and behaviour at both business and personal levels. With the use of modern technology such as the printing press and the highly mechanized harvesting of wood, disposable paper became a relatively cheap commodity, which led to a high level of consumption and waste. The rise in global environmental issues such as air and water pollution, climate change, overflowing landfills and clearcutting have all lead to increased government regulations. There is now a trend towards sustainability in the pulp and paper industry as it moves to reduce clear cutting, water use, greenhouse gas emissions, fossil fuel consumption and clean up its influence on local water supplies and air pollution.

COPERT is an MS Windows software program aiming at the calculation of air pollutant emissions from road transport. The technical development of COPERT is financed by the European Environment Agency (EEA), in the framework of the activities of the European Topic Centre on Air and Climate Change. Since 2007, the European Commission's Joint Research Centre has been coordinating the further scientific development of the model. In principle, COPERT has been developed for use from the National Experts to estimate emissions from road transport to be included in official annual national inventories. The COPERT methodology is also part of the EMEP/CORINAIR Emission Inventory Guidebook. The Guidebook, developed by the UNECE Task Force on Emissions Inventories and Projections, is intended to support reporting under the UNECE Convention on Long-Range Transboundary Air Pollution and the EU directive on national emission limits. The COPERT methodology is fully consistent with the Road Transport chapter of the Guidebook. The use of a software tool to calculate road transport emissions allows for a transparent and standardized, hence consistent and comparable data collecting and emissions reporting procedure, in accordance with the requirements of international conventions and protocols and EU legislation.

<span class="mw-page-title-main">Environmental effects of shipping</span> Ocean pollution

The environmental effects of shipping include air pollution, water pollution, acoustic, and oil pollution. Ships are responsible for more than 18% of nitrogen oxides pollution, and 3% of greenhouse gas emissions.

<span class="mw-page-title-main">Air quality law</span> Type of law

Air quality laws govern the emission of air pollutants into the atmosphere. A specialized subset of air quality laws regulate the quality of air inside buildings. Air quality laws are often designed specifically to protect human health by limiting or eliminating airborne pollutant concentrations. Other initiatives are designed to address broader ecological problems, such as limitations on chemicals that affect the ozone layer, and emissions trading programs to address acid rain or climate change. Regulatory efforts include identifying and categorising air pollutants, setting limits on acceptable emissions levels, and dictating necessary or appropriate mitigation technologies.

Daycent is a daily time series biogeochemical model used in agroecosystems to simulate fluxes of carbon and nitrogen between the atmosphere, vegetation, and soil. It is a daily version of the CENTURY biogeochemical model.

The United States Environmental Protection Agency (EPA) began regulating greenhouse gases (GHGs) under the Clean Air Act from mobile and stationary sources of air pollution for the first time on January 2, 2011. Standards for mobile sources have been established pursuant to Section 202 of the CAA, and GHGs from stationary sources are currently controlled under the authority of Part C of Title I of the Act. The basis for regulations was upheld in the United States Court of Appeals for the District of Columbia in June 2012.

<span class="mw-page-title-main">Environmental issues in Kuwait</span>

Located in the Middle East, Kuwait is a relatively small country that has been the center of many political and economic issues over the past few decades. Stemming from these tensions, Kuwait as well as other countries in the region, including Iran, Iraq, and Qatar face threats from environmental issues. A loss of agriculture due to climate change, pollution from the country's oil industry and Oil Fires of 1991 as well as damages to agriculture and biodiversity are just some of the common environmental issues. The Kuwaiti government has worked to mitigate and adapt to these issues through policy and the creation of agencies to research, educated and inform about environmental problems, their sources, and their effects.

<span class="mw-page-title-main">Sustainable Development Goal 13</span> UN goal to combat climate change

Sustainable Development Goal 13 is to limit and adapt to climate change. It is one of 17 Sustainable Development Goals established by the United Nations General Assembly in 2015. The official mission statement of this goal is to "Take urgent action to combat climate change and its impacts". SDG 13 and SDG 7 on clean energy are closely related and complementary.