What greenhouse gas is primarily emitted by agricultural and livestock activities?

Roles Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Software, Visualization, Writing – original draft, Writing – review & editing * E-mail: Affiliation Department of Molecular and Cell Biology, Department of Integrative Biology, Howard Hughes Medical Institute, University of California, Berkeley, CA, United States of America Animal agriculture contributes significantly to global warming through ongoing emissions of the potent greenhouse gases methane and nitrous oxide, and displacement of biomass carbon on the land used to support livestock. However, because estimates of the magnitude of the effect of ending animal agriculture often focus on only one factor, the full potential benefit of a more radical change remains underappreciated. Here we quantify the full “climate opportunity cost” of current global livestock production, by modeling the combined, long-term effects of emission reductions and biomass recovery that would be unlocked by a phaseout of animal agriculture. We show that, even in the absence of any other emission reductions, persistent drops in atmospheric methane and nitrous oxide levels, and slower carbon dioxide accumulation, following a phaseout of livestock production would, through the end of the century, have the same cumulative effect on the warming potential of the atmosphere as a 25 gigaton per year reduction in anthropogenic CO 2 emissions, providing half of the net emission reductions necessary to limit warming to 2...

In recent decades, atmospheric concentrations of certain gases have increased rapidly to levels that have not been seen before. It is believed that increasing greenhouse gas (GHG) concentrations will trap heat in the atmosphere and could lead to increased global warming and climate change. As a result, agriculture and other sectors of the economy are under pressure to reduce GHG emissions. Agriculture Contributes to GHG Emissions Agricultural activities contribute directly to GHG emissions through a variety of processes including enteric fermentation in domestic livestock, livestock/poultry manure management, agricultural soil management, field burning of agricultural residues, and rice cultivation. The U.S. EPA (2021) estimated that, in 2019, the agriculture sector was responsible for 9.6 percent of total U.S. GHG emissions. Even though the contribution of agriculture is small compared to some other sectors, understanding how GHGs are generated and what the poultry industry can do to further reduce its contribution is of great importance. This is true, in part, because livestock and poultry manures are an important source of GHG emissions. In addition to methane and nitrous oxide, ammonia is also produced from animal manures. Ammonia decomposes after deposition in soil or oxidizes in the air and can produce nitrous oxide, indirectly affecting production and emission of GHGs (Xie et al., 2002). Ammonia is also one of the main sources of fine particulate matter formation (Z...

March 9, 2021 The report was co-authored by Francesco Tubiello, a senior statistician and climate change specialist at the UN Food and Agriculture Organization (FAO), in collaboration with researchers at the European Commission's Joint Research Centre in Ispra, Italy. It presents a database, known as EDGAR FOOD, which can be used to assess how changes in consumer behaviour or technology, may impact food system-derived greenhouse gas emissions. EDGAR FOOD incorporates key land-use data for over 245 countries that has been compiled by FAO. The information goes back to 1990 and spans multiple sectors, which will enable tracking of ongoing and future trends. Food systems more energy intensive The report highlights how global food systems are becoming more energy intensive, reflecting trends in retail, packaging, transport and processing, whose emissions are growing rapidly in some developing countries. Roughly two-thirds of food system emissions come from agriculture, land use and changes in land use. The figure is higher for developing countries, but is also declining significantly as deforestation decreases and food processing, refrigeration and other “downstream activities” increase. In terms of the share of all ‘anthropogenic’ emissions, caused by human activity, food systems in industrial nations are broadly stable at around 24 per cent. In developing countries, the share has decreased from 68 per cent in 1990 to 39 per cent in 2015, partly due to very high increases in n...

Piers M. Forster , Christopher J. Smith, Tristram Walsh, William F. Lamb, Robin Lamboll, Mathias Hauser, Aurélien Ribes, Debbie Rosen, Nathan Gillett, Matthew D. Palmer, Joeri Rogelj, Karina von Schuckmann, Sonia I. Seneviratne, Blair Trewin, Xuebin Zhang, Myles Allen, Robbie Andrew, Arlene Birt, Alex Borger, Tim Boyer, Jiddu A. Broersma, Lijing Cheng, Frank Dentener, Pierre Friedlingstein, José M. Gutiérrez, Johannes Gütschow, Bradley Hall, Masayoshi Ishii, Stuart Jenkins, Xin Lan, June-Yi Lee, Colin Morice, Christopher Kadow, John Kennedy, Rachel Killick, Jan C. Minx, Vaishali Naik, Glen P. Peters, Anna Pirani, Julia Pongratz, Carl-Friedrich Schleussner, Sophie Szopa, Peter Thorne, Robert Rohde, Maisa Rojas Corradi, Dominik Schumacher, Russell Vose, Kirsten Zickfeld, Valérie Masson-Delmotte, and Panmao Zhai Intergovernmental Panel on Climate Change (IPCC) assessments are the trusted source of scientific evidence for climate negotiations taking place under the United Nations Framework Convention on Climate Change (UNFCCC), including the first global stocktake under the Paris Agreement that will conclude at COP28 in December 2023. Evidence-based decision-making needs to be informed by up-to-date and timely information on key indicators of the state of the climate system and of the human influence on the global climate system. However, successive IPCC reports are published at intervals of 5–10 years, creating potential for an information gap between report cycles. We follow...