Tuesday Talks with Dr. Patterson

December 2, 2014


Last month, on November 12, President Obama and Chinese President Xi Jinping surprised the world when they announced a broad agreement to reduce greenhouse gas (GHG) emissions by 2030. In the agreement, the U.S. pledged to reduce carbon dioxide emissions by 26 to 28 percent below 2005 emission levels; China pledged to limit growth in emissions by 2030 or sooner and to expand its share of non-fossil fuels used for energy consumption to about 20 percent by 2030. The agreement by these two countries is a significant event. China is the world’s biggest greenhouse-gas polluter; the United States is the second largest contributor. Combined they account for more than one-third of global GHG emissions. At the announcement of the agreement at the Asia-Pacific Economic Cooperation summit, President Obama said that he hopes this agreement will serve to encourage other countries to agree to reduce GHG emissions at the United Nations Climate Conference in Paris in late 2015. (Enoch)

Climate change and the contributions of greenhouse gases to climate change have been an important source of scientific inquiry and an issue of debate among policymakers. The majority of the scientific community has concluded that the global climate is changing and that GHG emissions are a contributing factor to this phenomena. Among policymakers, some still question whether climate is changing; some still question whether it is influenced by man’s emissions of greenhouse gases or that it is anthropogenic; some simply question whether there is an appropriate role for policy in reducing GHG emissions.

NOAA and NASA data indicate that the average surface temperature of the earth increased by 1.3° F during the last century. If growth in GHG emissions continues at their current rate, the average surface temperature is expected to increase by 7.2° F by the end of the current century (USDA ERS). This change in temperature and the associated change in weather patterns are expected to disrupt crop and livestock production. Higher temperatures reduce the ability of livestock to gain weight, reproduce, or produce milk. Crops will be challenged, as higher temperatures and more prevalent drought conditions will reduce crop yields. Under these conditions, the latest report of the United Nation’s Intergovernmental Panel on Climate Change predicts that agricultural production will fall by 2 percent per decade for the rest of the century. This will occur as global demand for food will grow by 14 percent during each decade with a growing global population (Gillis). These predictions signal the potential for significant disruptions in food supplies. Climate change and the more extreme weather patterns it is expected to produce are also expected to expose the U.S. government and private insurers to higher crop insurance claims in the coming years (Agri-Pulse 2014a).

While climate change can have a significant effect on agricultural production. Agriculture is also an appreciable contributor to GHG emissions. Indeed, agriculture is estimated to account for as much as 10 percent of GHG emissions in the United States in 2012. Livestock production results in methane gas emissions and crop activities result in emissions of nitrous oxide, due primarily to the use of nitrogen fertilizers; both are GHGs (USDA ERS).

Agriculture and forestry can also play a significant role in reducing atmospheric carbon dioxide. Forests and grasslands are particularly important in this regard by removing atmospheric carbon dioxide. Indeed, the USDA, General Motors, and Ducks Unlimited announced a project on November 17, whereby owners of grasslands may receive credit for the carbon this land will store. The carbon credits will be quantified and made available to entities wishing to purchase them to offset other carbon producing activities. This type of market could arise from policies which place limits on carbon emissions–the so-called cap and trade policy options. Similarly, some private firms are already purchasing carbon credits to offset some of their carbon emissions in response to customer demands. The sale of carbon credits gives landowners a new source of revenue. The landowners would also retain the right to work these lands through activities such as grazing or growing hay. In addition to sequestering carbon, the grasslands also provide improved habitat for wildlife (Agri-Pulse 2014b).

Opponents of policies to limit GHG emissions have characterized them as limiting economic growth. Some in Congress have argued that they would not support U.S. policies to limit GHG emissions, as long as other countries, notably China, did not make similar efforts to limit GHG emissions. The agreement announced last month by President Obama and President Jinping seems to signal a new level of cooperation by China. It remains to be seen how U.S. policymakers, notably Congress, will respond.

In addition to policies to reduce GHG emissions, including those attributable to agricultural production activities, new efforts to produce inputs and technologies that will assist agriculture in adjusting to climate change will be needed. This may entail the development of new crop varieties that are more tolerant to higher summer temperatures and drought conditions or animal production systems that reduce the effects of heat stress. This too may be another call for policy to support new agricultural research needed to assist producers in responding to climate change. Again, we are waiting to see how policymakers will respond.


Agri-Pulse. “Climate Change Could Increase Exposure to Crop Insurance Losses, GAO Report Says.” Agri-Pulse, November 20, 2014a. (Accessed November 30): http://www.agri-pulse.com/Climate-change-could-increase-exposure-to-crop-insurance-losses-GAO-report-says-11202014.asp

Agri-Pulse. “USDA, Chevrolet and Ducks Unlimited Help Ranchers Sell Carbon Credits.” Agri-Pulse, November 17, 2014b. (Accessed November 30, 2014): http://www.agri-pulse.com/USDA-Chevy-Duck-Unlimited-ranchers-sell-carbon-credits-11172014.asp

Enoch, D. “U.S., China Reach ‘Milestone’ Climate-Change Agreement.” Agri-Pulse, November 12, 2014. (Accessed November 30, 2014): http://www.agri-pulse.com/US-and-China-reach-milestone-climage-change-agreement-11122014.asp

Gillis, J. “Climate Change Seen Posing Risk to Food Supplies.” New York Times, November 1, 2013. (Accessed November 30, 2014): http://www.nytimes.com/2013/11/02/science/earth/science-panel-warns-of-risks-to-food-supply-from-climate-change.html?module=Search&mabReward=relbias%3Aw%2C%7B%221%22%3A%22RI%3A10%22%7D&_r=0

U.S. Department of Agriculture, Economic Research Service. Climate Change: Background

Dr. Paul Patterson is associate dean for instruction for the College of Agriculture and Professor of Agricultural Economics.