GHG Reporting Program Data and U.S. Greenhouse Gas Emissions Inventory
Report: A Comparison
The U.S. Environmental Protection Agency's (EPA) Greenhouse Gas Reporting Program
(GHGRP) collects and disseminates annual greenhouse gas (GHG) data from individual facilities
and suppliers across the U.S. economy. EPA also develops the annual Inventory of U.S.
Greenhouse Gas Emissions and Sinks (Inventory) to track total national emissions of
greenhouse gases to meet U.S. government commitments to the United Nations Framework
Convention on Climate Change. The GHGRP and Inventory datasets are complementary and
may inform each other over time. However, there are also important differences in the data and
approach. These differences are highlighted here to help stakeholders understand these data
sources and use them appropriately.
Key differences between GHGRP data and the U.S. GHG Inventory:
	Approach to collecting and reporting data. The U.S. GHG Inventory is largely
developed with a "top down" approach using aggregated national data to develop
emissions estimates for the entire U.S. economy. For many sources, the Inventory data
cannot be broken down to show emissions by facility. The GHGRP uses a "bottom up"
approach. It collects GHG data for every facility and supplier that is required to report,
which allows the data to be grouped and categorized in a variety of useful ways
including by facility, location, and industry group.
	The percentage of U.S. GHG emissions covered. The U.S. GHG Inventory provides a
comprehensive picture of all GHG emissions and covers 100 percent of man-made
emissions in the U.S. The 2010 GHGRP data covers roughly 80 percent of total U.S.
GHG emissions. This is because the GHGRP only requires reporting from large direct
emitters of GHGs from certain industries and suppliers of certain fossil fuels and
industrial gases. Direct emitters in the GHGRP report roughly half of total U.S.
emissions; additional GHG data is reported by the suppliers. In addition, 12 new industry
groups are required to report 2011 GHG emissions data in 2012 for the first time. The
GHGRP does not include GHG emissions from certain diffuse sources such as
agricultural soil management and enteric fermentation by livestock.
	Inclusion of forestry and land use. The Inventory tracks national greenhouse gas
emissions associated with land use and land use change and sequestration of carbon
dioxide in forests and other managed lands. As displayed in the 2009 Inventory, this
sector absorbed 1,015 million metric tons of C02. The GHGRP data does not include
data related to emissions or absorption of GHGs on forests and other lands.
	The timeframe of emissions data. The GHGRP began in 2010 and will collect data
annually going forward. Facilities are not required to estimate emissions for years prior
to 2010. The current U.S. GHG Inventory presents national estimates starting in 1990
and for each subsequent year through 2009. The next U.S. GHG Inventory, covering
2010 data, will be released for public review in February 2012 and finalized in April 2012.
	The procedures for calculating emissions. Both the U.S. GHG Inventory and the
GHG Reporting Program use methodologies that are consistent with the internationally

agreed upon procedures developed by the Intergovernmental Panel on Climate Change
(IPCC). For the GHG Reporting Program, facilities collect detailed information specific
to their operations (e.g., natural gas used by a plant) according to detailed measurement
standards, whereas the data collected for the U.S. GHG Inventory are at a more
aggregated level (e.g., natural gas used by the country).
 Definitions of sectors and industry groupings. The definitions of sectors and
industry groupings in the Inventory and the GHGRP data are not always the same.
Users should check the definitions of industry sectors in the two data sets before making
For more information on the GHG Reporting Program, please visit these additional
-	Frequently asked questions on the GHGRP Publication Tool
-	GHG Reporting Program and Data Publication Fact Sheet