A413. The U.S. GHG Inventory is EPA's official source of total U.S. emissions. The Inventory is developed using (primarily) top-down methods and covers all sectors of the economy. Based on the Inventory: electricity generation accounts for approximately 30% of U.S. emissions, transportation accounts for approximately 26%, industry accounts for approximately 21%, commercial and residential sources account for approximately 12%, and agriculture accounts for the remaining 9%. For more information: http://www3.epa.gov/climatechange/ghgemissions/sources.html.
The GHG reporting program (GHGRP) is developed using bottom-up methods and covers roughly 85 to 90 percent of total U.S. GHG emissions. This includes direct emissions data reported by stationary sources - including nearly all emissions from electricity generation and most emissions from industry which account for roughly 50% of total U.S. emissions. This also includes GHG data reported by suppliers of fossil fuels and industrial gases - which accounts for the vast majority of emissions from transportation, commercial and residential sources, roughly 35-40% of total U.S. emissions. The GHGRP does not include emissions from the agriculture and land use sectors, or other small sources of emissions. Note that the data for direct emitting stationary sources is housed in a separate section of FLIGHT from the suppliers of fuels and other industrial gases. The default view of the GHG data in FLIGHT includes emissions reported by direct emitters only. For more information: http://www3.epa.gov/climatechange/ghgemissions/usinventoryreport.html.