The U.S. Environmental Protection Agency (EPA) recently released its 29th annual inventory of U.S. greenhouse gas emissions and sinks, which offers a national level overview of annual greenhouse gas emissions from 1990 to 2020.
EPA reported that net U.S. greenhouse gas emissions were 5,222.4 million metric tons of carbon dioxide equivalent in 2020, a nearly 11% decrease in emissions from 2019.
The sharp decline in emissions from 2019 to 2020 is largely due to the impacts of the coronavirus pandemic on travel and economic activity. “However, the decline also reflects the combined impacts of several factors, including population trends, energy market trends, technological changes including energy efficiency improvements, and the carbon intensity of energy fuel choices,” EPA said.
For the latest release, EPA said that it has made several important improvements. For example, EPA has added estimates for two important sources of methane: emissions from post-meter uses of natural gas, which includes leak emissions from residential and commercial appliances, industrial facilities and power plants, and natural gas fueled vehicles; and emissions from flooded lands such as hydroelectric and agricultural reservoirs.
Additionally, EPA worked with researchers to include estimates of methane emissions from large anomalous leak events, such as well blow-outs.
The GHG inventory covers seven key greenhouse gases: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, sulfur hexafluoride, and nitrogen trifluoride.
In addition to tracking U.S. greenhouse gas emissions, the inventory also calculates carbon dioxide that is removed from the atmosphere through the uptake of carbon in forests and other vegetation.
The report has been compiled annually since 1993 and submitted to the United Nations Framework Convention on Climate Change (UNFCCC).
The report is prepared by EPA in collaboration with numerous experts from other federal agencies, state government authorities, research and academic institutions, and industry associations.
Click here for additional details about the inventory.
