Skip to main content
ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Soil Management and Sugarbeet Research » Research » Publications at this Location » Publication #323403

Title: Chapter 1: Introduction and Summary

Author
item Del Grosso, Stephen - Steve
item BARANSKI, MARCI - Office Of The Chief Economist
item EVE, MARLEN - Office Of The Chief Economist
item Reyes-Fox, Melissa

Submitted to: Government Publication/Report
Publication Type: Government Publication
Publication Acceptance Date: 5/2/2016
Publication Date: N/A
Citation: N/A

Interpretive Summary: Global concentrations of the three most important long-lived greenhouse gases (GHG) in the atmosphere have increased measurably since the onset of the Industrial revolution. In 2013, total U.S. greenhouse gas emissions were 6,673 million metric tons of carbon dioxide equivalents (MMT CO2 eq.), rising 5.9 percent from 1990 estimates. Agriculture and forestry practices may either contribute to or remove GHG from the atmosphere. Agriculture and forestry have contributed to GHG levels in the atmosphere through cultivation and fertilization of soils, production of ruminant livestock, management of livestock manure, land use conversions, and fuel consumption. The primary GHG sources for agriculture are N2O emissions from cropped and grazed soils (~44%), CH4 emissions from ruminant livestock production and rice cultivation (~29%), and CH4, N2O emissions from managed livestock waste (~13%) and CO2 emissions from on farm energy use (~13%). The management of cropped, grazed, and forestland has helped offset GHG emissions by promoting the biological uptake of carbon dioxide (CO2) through the incorporation of carbon into biomass, wood products, and soils, yielding a U.S.net emissions (sources minus sink)of 5,803 MMT CO2 eq. This report serves to estimate U.S. GHG emissions for the agricultural sector, to quantify uncertainty in emission estimates, and to estimate the potential of agriculture to mitigate U.S. GHG emissions.

Technical Abstract: In 2013, total U.S. greenhouse gas emissions measured 6,673 million metric tons of carbon dioxide equivalents (MMT CO2 eq.), rising 5.9 percent from 1990 estimates. Global concentrations of the three most important long-lived greenhouse gases (GHG) in the atmosphere have increased measurably since the onset of the Industrial revolution in 1750. Carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) concentrations in the atmosphere have increased by approximately 43%, 152%, and 20% respectively. Agriculture and forestry practices may either contribute to or remove GHG from the atmosphere. Agriculture and forestry have contributed to GHG levels in the atmosphere through cultivation and fertilization of soils, production of ruminant livestock, management of livestock manure, land use conversions, and fuel consumption. The primary GHG sources for agriculture are N2O emissions from cropped and grazed soils (~44%), CH4 emissions from ruminant livestock production and rice cultivation (~29%), and CH4, N2O emissions from managed livestock waste (~13%) and CO2 emissions from on farm energy use (~13%). The management of cropped, grazed, and forestland has helped offset GHG emissions by promoting the biological uptake of CO2 through the incorporation of carbon into biomass, wood products, and soils, yielding a U.S.net emissions of 5,803 MMT CO2 eq. Net emissions equate to total greenhouse gas emissions minus CO2 sequestration or removal of CO2 from the atmosphere including the net forest sink as well as the net soil sink from grazed lands and croplands. This report serves to estimate U.S. GHG emissions for the agricultural sector, to quantify uncertainty in emission estimates, and to estimate the potential of agriculture to mitigate U.S. GHG emissions.