Information on emissions therefore is an absolute requirement in understanding environmental problems and in monitoring progress towards solving these.
Emission inventories are developed for a variety of purposes: 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.
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 such cases data on time dependent traffic intensities (rush hours, weekends and working days, summer and winter driving patterns, etc.)
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.
Both the UNFCCC and LRTAP conventions require an inventory to follow the quality criteria below (see[4]): 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.