Natural Gas and Petroleum Systems in the GHG Inventory: Additional Information on the 1990-2021 GHG Inventory (published April 2023)

As part of the annual process to develop the U.S. Inventory of Greenhouse Gas Emissions and Sinks (GHG Inventory), EPA assessed new data for updates to its estimates for natural gas systems, petroleum systems, and abandoned oil and gas wells.

Please see the memo below for information on these updates. The natural gas systems, petroleum systems, and abandoned oil and gas wells methodology annexes for the 1990-2021 GHG Inventory are available below as well. The natural gas systems and petroleum systems annexes include both national-level data and basin-level data, as applicable.

For previously posted information from the stakeholder process, view the archives of memos and presentation slides regarding updates considered for the 1990-2021 GHG Inventory.

View information about revisions to estimates for natural gas and petroleum systems in the GHG Inventory for earlier Inventory release years.

Methodology Annexes

• Annex 3.5: Methodology for Estimating CH4, CO2, and N2O emissions from Petroleum Systems
• Annex 3.6: Methodology for Estimating CH4, CO2, and N2O Emissions from Natural Gas Systems
• Methodology for Estimating CH4 and CO2 Emissions from Abandoned Oil and Gas Wells (xlsx) (56.85 KB)

Memo on updates to estimates for natural gas systems, petroleum systems, and abandoned oil and gas wells

• Inventory of U.S. Greenhouse Gas Emissions and Sinks 1990-2021: Updates to Incorporate Additional Geographically Disaggregated Data for the Production Segment (pdf) (437.58 KB)