Glossary


 * Biogenic carbon** is that carbon produced by life processes sourced from constituents, or secretions, of plants or animals. Carbon dioxide released when wood is combusted, for example, is considered "biogenic". By contrast, carbon dioxide released from the combustion of coal is not.


 * Consumption** is defined in economic circles as the final purchase of goods or services. In this definition, consumers are primarily limited to households (individuals) and governments. The vast majority of purchases by businesses are not consumption, but one small category is: investment purchases, or the equipment or inventory that businesses purchases but do not sell in the same year.


 * Consumption-based inventory** covers the total global GHG emissions occurring from economic consumption within a set region, such as a country. Consumption based inventories attempt to estimate all emissions - both inside and outside the community - that arise as a consequence of consumption activities within that community. For a comparison with systems-based inventories, see the consumption and systems inventories page.


 * Degradable organic carbon** is the portion of organic carbon present in such solid waste as paper, food waste, and yard waste. In landfills, a fraction of this degradable organic carbon decomposes anaerobically and releases methane and carbon dioxide. The fraction that decomposes depends on the waste type.


 * Downstream emissions** can be important to the manufacturer or the consumer, and may be scoped differently for each entity. For a manufacturer, downstream emissions are the individual or aggregate GHG emissions attributable to the distribution, use, and disposal of products. From the consumer's perspective, downstream emissions are emissions associated with disposal.


 * Embodied energy** is the available energy that was used in the work of making a product. Embodied energy uses an accounting methodology which aims to find the sum total of the energy necessary for an entire product lifecycle. This lifecycle includes raw material extraction, transport, manufacture, assembly, installation, disassembly, deconstruction and/or decomposition.


 * Geographic/production based inventory** is an emission inventory that accounts for emissions physically originating within the geographic boundaries of the community. National inventories are typically geographic.


 * Global warming potential (GWP)** is a is an index of how potent a greenhouse gas is compared to the same mass of carbon dioxide (for example, one kilogram of the GHG versus one kilogram of CO2), over time. By definition, the GWP of CO2 is 1. GWPs depend on the specified timeframe, and 100-year GWPs are conventionally used. For example, methane has a 100-year GWP of 25, indicating that one kilogram of methane is 25 times more potent than one kilogram of CO2, when its effect is averaged out over 100 years. The rationale often cited for 100-year GWPs is that the atmospheric lifetime of CO2 is around 100 years. Yet methane's atmospheric lifetime is shorter, on the scale of 12 years, so that methane does its damage during the early years. Shorter timeframes account for this short-lived impact, and the 20-year GWP for methane is higher, at 72.


 * Input/output analysis** is one of a set of related methods which show how the parts of a system are affected by a change in one part of that system. Input-output analysis specifically shows how industries are linked together through supplying inputs for the output of an economy.


 * Materials management** is "an approach to serving human needs by using/reusing resources most productively and sustainably throughout their life cycles, generally minimizing the amount of materials involved and all the associated environmental impacts" (EPA 2009a). It addresses the flow of materials and goods through the economy, including but not limited to industrial process waste and solid waste management. The purview is the total amount of materials in the U.S. domestic economy, including all imported and domestically-sourced raw materials that underwent some form of manufacturing transformation, net of exports. This is estimated to be on the order of 6.5 billion tons annually (WRI 2008). The end point of most economic activity involving materials is goods, or products and packaging. When discarded, products and packaging represent 73 percent of the “solid waste” material managed by local governments, which all together is a tiny fraction of the flow of materials through the economy (//Char. MSW//, EPA 2008).


 * Methane commitment (MC)** is a method of assigning GHG emissions to a landfill, and is based on waste disposed in a given year. It takes a lifecycle approach and counts GHGs emitted by that waste, regardless of when the emissions occur, and assigns it to the year in which the waste is placed in the landfill. For more information, see WIP and MC page.


 * Non-energy-use GHG emissions** are those GHG emissions not associated with energy production or use, but are associated with some industrial processes. For example, carbon dioxide (CO2) is released during conversion of limestone to lime, perfluorocarbon emissions are released during production of aluminum, magnesium, semiconductors, and other products, and methane emissions from natural gas processing associated with the manufacture of plastic products.


 * Per capita emissions** are the total annual emissions divided by a mid-year population of a defined region, such as a county, state, country. Per capita emissions may be based on historical or annual emissions.


 * Product stewardship** is the act of minimizing health, safety, environmental and social impacts, and maximizing economic benefits of a product and its packaging throughout all lifecycle stages. Product stewardship assigns responsibility for minimizing a product’s environmental impact throughout all stages of its life to the private chain of commerce (producers, retailers, consumers, etc.), recognizing that the producer of a product has the greatest ability to minimize these adverse impacts. **Extended producer responsibility (EPR)** is a mandatory type of product stewardship that requires, at a minimum, that the producer’s responsibility for their product extends to post-consumer management of that product and its packaging. EPR policy requires shifting financial and management responsibility, with government oversight, upstream to the producer and away from the public sector, and providing incentives to producers to incorporate environmental considerations into the design of their products and packaging.


 * Scope 3:** Institutional GHG inventory reporting systems classify emissions depending on where they originate. Scope 1 emissions (or "direct emissions") are from sources that the institution controls or owns. Scope 2 emissions (or "indirect emissions") are those generated from purchased energy that the institution consumes. **Scope 3** emissions are all other indirect emissions, including contributions from material-related upstream emissions, waste management emissions, emissions from air travel and commuting, and emissions from out-sourced activities. Reporting of Scope 3 emissions are optional in some GHG inventory reporting systems, and if reported, must be clearly defined as to which Scope 3 emissions are included.


 * Systems-based inventory** is an emissions inventory where systems represent and comprise all the parts of the economy working to fulfill a particular need. For example, the provision of food system includes all emissions from the electric power, transportation, industrial, and agricultural sectors associated with growing, processing, transporting, and disposing of food. The systems view is helpful for framing opportunities to reduce GHG emissions through prevention‐oriented mitigation strategies that act across an entire system. For a comparison with consumption-based inventories, see the consumption and systems inventories page.


 * Upstream emissions** can be important to the manufacturer or the consumer, and may be scoped differently for each entity. For a manufacturer, upstream emissions are the individual or aggregate GHG emissions attributable to the inputs and activities prior to manufacturing of products such as: material extraction, transportation of materials to manufacturing site, and other supply chain activities resulting in delivery of raw materials and supplies and energy/fuel/water to the manufacturing site. From the consumer's perspective, upstream emissions will include all of the above plus impacts of distribution to the point of purchase and to the product's site of use.


 * Waste In Place (WIP) Methodology** (for landfills) is a method of assigning GHG emissions to a landfill, and is based on actual emissions from the landfill during a given year, regardless of when the waste was disposed. For more information, see WIP and MC page.


 * Waste management** is a subset of "materials management" (see above), specifically addressing the management of "wastes" or "discards" when the waste generator no longer wants them. The term "waste management" is often used to apply to all discards, including garbage, composting, and recycling. The term is sometimes applied more narrowly, specific just to "garbage", as some recycling professionals oppose classifying recyclables as "waste" or recycling as "waste management".