Gases that trap heat in the atmosphere are often called greenhouse gases. Some greenhouse gases such as carbon dioxide occur naturally and are emitted to the atmosphere through natural processes and human activities. Other greenhouse gases (e.g., fluorinated gases) are created and emitted solely through human activities. The principal greenhouse gases that enter the atmosphere because of human activities are:
A greenhouse gas inventory is an accounting of the amount of greenhouse gases emitted to or removed from the atmosphere over a specific period of time (e.g., one year). A greenhouse gas inventory also provides information on the activities that cause emissions and removals, as well as background on the methods used to make the calculations. Policy makers use greenhouse gas inventories to track emission trends, develop strategies and policies and assess progress. Scientists use greenhouse gas inventories as inputs to atmospheric and economic models.
The Community is planning to collect emissions data from sources of greenhouse gases (GHGs). These data collection programs have differing reporting requirements, thresholds, calculation protocols, and approaches to validation and verification of data. Despite these differences, the data collections share a common objective—improved tracking and understanding of GHG emissions. Ultimately, the information collected will form the foundation to curb the emission of GHGs. With a standardized approach for sharing information, the Community will have access to a more comprehensive and robust GHG data set . Furthermore, a common approach to data exchange may offer opportunities to unify or simplify reporting tools. GHG reporters and Community members expect data collectors to work together to maximize the efficiency and accuracy of systems for collecting and sharing GHG emissions information.