That is a new page, apparently written in 2021 by the present administration.

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Nitrous Oxide Emissions

Properties of Nitrous Oxide
Chemical Formula: N2O
Lifetime in Atmosphere: 114 years
Global Warming Potential (100-year): 2981
In 2019, nitrous oxide (N2O) accounted for about 7 percent of all U.S. greenhouse gas emissions from human activities. Human activities such as agriculture, fuel combustion, wastewater management, and industrial processes are increasing the amount of N2O in the atmosphere. Nitrous oxide is also naturally present in the atmosphere as part of the Earth's nitrogen cycle, and has a variety of natural sources. Nitrous oxide molecules stay in the atmosphere for an average of 114 years before being removed by a sink or destroyed through chemical reactions. The impact of 1 pound of N2O on warming the atmosphere is almost 300 times that of 1 pound of carbon dioxide.1
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Nitrous oxide emissions in the United States have remained relatively flat between 1990 and 2019.

Nitrous oxide emissions from mobile combustion decreased by 60 percent from 1990 to 2019 as a result of emission control standards for on-road vehicles.

Nitrous oxide emissions from agricultural soils have varied during this period and were about 9 percent higher in 2019 than in 1990, primarily driven by increasing use of nitrogen fertilizers.

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