Submitted to: Government Publication/Report
Publication Type: Other
Publication Acceptance Date: 4/15/2008
Publication Date: 5/27/2008
Citation: Hatfield, J.L., Boote, K.J., Kimball, B.A., Wolfe, D.W., Ort, D.R., Izaurralde, C.R., Thomson, A.M., Morgan, J.A., Polley, H.W., Fay, P.A., Mader, T.L., Hahn, G.L. 2008. Agriculture. In: The effects of climate change on agriculture, land resources, water resources, and biodiversity. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research, Washington, DC. 362 p. Interpretive Summary:
Technical Abstract: Agriculture within the United States is varied and produces a large value ($200 billion in 2002) of production across a wide range of plant and animal production systems. Because of this diversity, changes in climate will likely impact agriculture throughout the United States. Climate affects crop, vegetable and fruit production, pasture production, rangeland production, and livestock production systems significantly because of the direct effects of temperature, precipitation, and CO2 on plant growth, and the direct effect of temperature and water availability to livestock. Variations in production between years in any of these commodities is a direct result of weather within the production period, and can often be an indirect result of weather effects on insects, diseases, or weeds. Temperature, CO2, and precipitation all affect plant growth, and changes in these factors can have either positive or negative impacts on plant growth and yield. Variation among plant species prevents a simple conclusion about the impacts of changes caused by these primary factors on future plant response to climate change. The variation in plant species and their distribution across the United States further complicates our ability to provide exact statements; however, there are general plant responses that can be expressed with a high degree of certainty. As temperature rises, crops will increasingly begin to experience higher temperatures beyond the optimum for their reproductive development, especially if climate variability increases, and if rainfall is reduced or becomes more variable. Under this situation, yield responses to temperature and CO2 will likely become more negative. The climate changes that matter most for ruminants are (1) general increase in temperature levels; (2) increases in nighttime temperatures; and (3) increases in occurrence of extreme events (e.g., hotter daily maximum temperature, and more/longer heat waves).