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The Potential Impacts of Climate Change on U.S. Agriculture: What Can Farmers Do About it? - September 29, 2003

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Introduction

Agenda

White Paper

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Lecture Videos

Agenda

Welcome and Introductions
Eric Chivian, Director, Center for Health and the Global Environment, Harvard Medical School

An Overview of Climate Change Impacts on U.S. Agriculture
William Easterling, Professor of Agronomy and Director of the Institutes of the Environment, Penn State University

Climate Change Effects on Crop Diseases and Pests
X.B. Yang, Assoc. Professor of Plant Pathology, Iowa State University

Carbon Sequestration on Farms
Charles W. Rice, Professor of Soil Microbiology, Kansas State University

Wind Energy and the Production of Biofuels
Dan McGuire, Chief Executive Officer, American Corn Growers Foundation

An Overview of Climate Change Impacts on U.S. Agriculture

Rainfall, warmth, and sunlight are as critical as fertilizer, pesticide and fuel to the success of farming. As deliveries of those climate resources are disrupted by droughts, freezes, or floods, costs to farmers and society rise. Climate variability continues to exert large year-to-year swings in U. S. crop yields and production in spite of impressive technology-driven gains in crop productivity over the 20th century. Recent persistent drought conditions in the western Corn Belt states have particularly affected wheat production. The USDA estimates that season-ending U. S. wheat stocks this year will be down 94 million bushels from July, caused by a combination of the aforementioned drought conditions and increased foreign demand (also caused in part by drought-induced production shortfalls in Europe). Season-ending U. S. corn and soybean stocks are projected to be higher than last year. Does this recent downturn in wheat production signal a trend toward tougher times ahead for U. S. agriculture? In the short-term, the answer is, not likely. In the long-term, the answer is, yes, maybe. It is difficult to discern long-term (decades or longer) changes in the frequency or intensity of droughts, heat waves or other extreme events in the climate record for the United States as a whole. There is evidence for the following long-term trends: a) an earlier start (~11 days) of the frost-free season and occurrence of fewer extreme cold days in the northeastern U. S.; b) an increase in one-day heavy precipitation (>1”) events nationally (by approximately 2-12% across the Corn Belt); c) a pronounced increase in minimum daily temperatures nationally (but no trend in maximum temperatures); and d) an increase in the area of the U. S. experiencing extreme wetness (but no change in dryness). What does the future climate hold for U. S. agriculture? Climate model simulations on the whole indicate that most mid-continental locations in the Northern Hemisphere (home to the world’s major grain production regions) will warm more than the global average and will receive more precipitation than current. The trend toward more high-intensity rainfall events is expected to continue. Droughts are likely to become more frequent in these regions, in spite of more rainfall, due to higher evapotranspiration. Critically, soils will eventually dry. Growing seasons likely will be extended, but the probability of destructive heat waves will rise. What do these potential changes bode for the nation’s crop production? Experiments persuasively demonstrate the positive effects of rising atmospheric CO2 concentrations on photosynthesis of certain major crops such as soybeans and wheat and on the drought-tolerance of all crops. However, these effects are not likely to fully offset the potential stresses of warmer temperatures and drier soils, especially as the warming progresses. An ensemble of crop simulation studies with explicit modeling of the interactive effects of temperature, precipitation and atmospheric CO2 concentration was assembled by the IPCC. The ensemble indicates a nominal increase in mid-latitude (including U. S. Midwest) corn and wheat yields for up to 1º C local warming in wheat and 2° C for corn. Further warming causes yields for both crops to fall below current levels. At +4º C, corn yields are 15% below current levels and wheat yields are 25% below current. Hence, the higher rainfall and increased warmth is beneficial for a while, but eventually the soils dry out and yields rapidly fall. A deficiency of studies such as those making up the above ensemble is that they presume that only the averages and not the variability of years around those averages will change; also, that farmers will take no steps to adapt to the climate change. Those deficiencies detract from realism of the simulations. Important new research simulates eastern U. S. Corn Belt corn and soybean yield response to climate change with change in variability and with the inclusion of a logical agronomic strategy (change in maturity class) to adjust. Corn yields under increased variability and an overall growing season warming of 2.8 degrees and a slight increase in rainfall decreased by as much as 45% across the southern states of the Corn Belt (due to extreme high temperatures) while increasing by as much as 45% across the northern states (due to the absence of extreme high temperatures). Soybeans were less negatively affected by the climate changes, although the increased variability also brought slightly lower yields in the southern states of the region. Crop modeling results as such are highly uncertain because they are dependent on the skill of the climate change prediction, they ignore key processes such as changes in pests and diseases, and they do not explicitly consider the effects of flooding, hail, extreme wind, and other climatic extremes. Moreover, they do not represent all of the possible adaptation strategies that farmers are likely to try. However, they do paint a consistent picture of crop yields being lower than today even in an environment with higher rainfall than now.

Suggested Readings and References
Adams, Richard M., B. H. Hurd, and J. Reilly. 1999. Agriculture & Global Climate Change: A Review of Impacts to U.S. Agricultural Resources, Pew Center on Global Climate Change, Washington, DC (http://www.pewclimate.org/docUploads/env%5Fargiculture%2Epdf).

Agriculture Assessment Team. 2002. Agriculture: The Potential Consequences of Climate Variability and Change for the United States. Report of the Agriculture Assessment Team of the US National Assessment. Cambridge University Press, New York.

Gitay, H., Sandra Brown, William Easterling, and Bubu Jallow et al. 2001. Ecosystems and Their Goods and Services. In McCarthy, J. J., Osvaldo F. Canziani, Neil A. Leary, David J. Dokken, Kasey S. White (eds.), Climate Change 2001: Impacts, Adaptation, and Vulnerability, Report of Working II of the Intergovernmental Panel on Climate Change, Cambridge University Press, New York.

Stern, P. and W. Easterling (eds.), 1999. Making Climate Forecasts Matter, Report of the Panel on the Human Dimensions of Seasonal-to-Interannual Climate Variability, National Academy Press, Washington, DC.

Dr. William E. Easterling is Professor of Geography and Agronomy and Director of the Institutes of the Environment at The Pennsylvania State University. He held posts in the Institute of Agriculture and Natural Resources at the University of Nebraska and at Resources for the Future in Washington DC. His research focuses on modeling the consequences of climate variability and change for agricultural production and on the use of weather and climate information in agricultural decision making. He was awarded the Wilson medal for excellence in research at Penn State last spring. He was the lead author on the agriculture chapter in the most recent assessment report of the Intergovernmental Panel on Climate Change. He has served on numerous boards and committees of the National Research Council and federal agencies.

Climate Change Effects on Crop Diseases and Pests

Agriculture pests (diseases, insects, and weeds) are one of the greatest threats to the success of US agriculture and are detrimental to our nation’s food security. The estimated loss from these pests in North America from 1988-1990 was 37% of potential crop values (annual loss of 22 billion dollars). Climate change will greatly impact plant diseases and pests because climate dictates their occurrence. Literature in plant pathology has shown that pandemics of pests are associated with extreme weather events. Recently, increased large scale epidemics of new and old diseases have been recorded in our nation’s major crops. Pandemics of wheat stripe rust occurred in The Great Plains during the 2001 and 2003 growing seasons. In 2002, U.S. soybean farmers experienced epidemics of soybean sudden death syndrome, and various viral diseases, costing nearly 2 billion dollars. This summer, mass outbreaks of Asian aphids occurred in Iowa, Illinois, and Minnesota, three largest soybean production states, after cool July weather suddenly turned into a record dry August.

Farmers in the North Central Region, that includes our nation’s Corn Belt and Soybean Belt, are experiencing increasing outbreaks of crop diseases and pests. Before the mid-80s, no more than four major diseases were limiting factors to soybean production. Now the number is more than doubled with annual losses near two billion dollars. Range expansion northward of southern diseases or distribution range expansion of warm-temperature diseases has been attributed to these new disease problems. Recent warmer winters in northern production regions have increased winter pest survival and outbreaks of insect-borne virus diseases associated with them.

Management of diseases and pests has become often impossible because of increased frequencies of unpredictable outbreaks and the emergence pace of new disease or pest problems. Emergence of new diseases and pests has surpassed our abilities and resources to develop control measures, regardless of farmers’ ability to pay for them. For instance, development of disease/insect resistance in soybeans, one of most effective control measures and one favorable to farmers, is practically meaningless because development of disease resistant varieties takes a minimum of five years. In comparison, current disease problems are often changed in one or two seasons.

References
Rosenzweig, C., Iglesias, A., Yang, X.B., Epstein, P.R. and Chivian, E. 2002. Climate changes and U.S. agriculture: the impacts of warming and extreme weather events on productivity, plant diseases, and pests. Global Change and Human Health 2: 90–105.

Wrather, J.A., Koenning, S.R., and Anderson, T.R. 2003. Effect of Diseases on Soybean Yields in the United States and Ontario (1999 to 2002). Plant Health Progress PHP-2003-0325-01-RV. http://www.plantmanagementnetwork.org/php/

Yang, X.B., and Feng, F. 2001. Ranges and diversity of soybean fungal diseases in North America. Phytopathology 91: 769–775.

Scherm, H. and Yang, X.B. 1995. Interannual variations in wheat rust development in China and the United States in relation to the El Nino/southern oscillation. Phytopathology 85: 970–976.

Dr. Yang is an associate professor of plant pathology at Iowa State University. He studies plant diseases and educates Iowa farmers and the soybean industry on managing crop diseases. He has published 92 technical papers and more than 250 non-technical articles. He has severed as a senior editor or a board member on four science journals. He has been awarded honorary professorships by prestigious universities in China and Thailand.

Carbon Sequestration on Farms

Concern has been mounting about the rapid buildup of carbon dioxide (CO2) in the atmosphere and the potential implications for climate and the environment. Currently, the amount of CO2 in the air is increasing by over 1500 million metric tons of carbon (MMT C) per year, mainly through the burning of fossil fuels (coal, oil and natural gas). Agriculture can help solve this problem. Crops and other plants remove CO2 from the atmosphere and convert it into organic carbon. After harvest, the organic carbon in residues and roots is deposited into the soil, where portions can remain for long periods. Carbon accumulation in agricultural soils can be greatly improved by various forms of conservation management, such as no-till and replanting with grasses. Conservation tillage, including no-tillage, can result in a buildup of 0.2 – 0.4 MT C/ha/y (0.1-0.2 T C/a/y). Grass plantings, such as the Conservation Reserve Program, can sequester up to 0.3-0.7 MT C/ha/y (0.15-0.3 T C/a/y). Additional benefits of carbon sequestration include increased soil fertility, reduced erosion, improved wildlife habitat and better soil and water quality.
Recent estimates of the potential for U.S. agricultural soils to sequester carbon, using existing technologies, are on the order of 200 MMT C per year which represents 15% of carbon emissions in the U.S. This estimate does not include biomass production for renewable fuels nor advancement in soil and agricultural sciences. Economic analysis suggests that soil carbon sequestration is among the most beneficial and cost effective options available for reducing greenhouse gases, particularly over the next 30 years until alternative energy sources are developed and become economically feasible.

Under a private emissions trading strategy, U.S. farmers, practicing appropriate conservation practices, could offer greenhouse gas or carbon credits to carbon emitters. Several companies have begun investing in carbon sequestration projects in the U.S. and abroad, on a voluntary basis. Early estimates indicate that the potential for a carbon "credits" market for U.S. agriculture is $1-5 billion per year for the next 20-40 years. Alternatively, government programs might be implemented to directly support farmers for adopting conservation practices. Either strategy would help mitigate the atmosphere’s greenhouse gas buildup while the needed long-term technical solutions are found for producing clean energy.

For more information see:
http://www.oznet.ksu.edu/ctec/
http://www.casmgs.colostate.edu/

Chuck Rice is Professor of Soil Microbiology in the Department of Agronomy at Kansas State University. He teaches courses in soil microbiology and conducts research on soil carbon and nitrogen transformations in agricultural and grassland ecosystems and microbial ecology. He is Fellow of the Soil Science Society of America and American Society of Agronomy. Dr. Rice currently serves as Director of the Consortium for Agricultural Soils Mitigation of Greenhouse Gases. This consortium is a 10 institution organization to conduct research on the potential of agricultural soil to sequester carbon dioxide while providing benefits to producers.

Wind Energy and the Production of Biofuels

Renewable energy, including wind, ethanol and biodiesel offer the means to improve the environment and make our country more energy independent and secure while enhancing the rural & national economy. Wind, ethanol and biodiesel offer these opportunities now:

Modern wind turbines extract the wind’s energy while helping the environment:

• The first farmer-owned wind farm at Pipestone, MN, with only two 750-kilowatt wind turbines, results in avoided emissions of about 4.8 million lbs. of carbon; 25,000 lbs. of sulfur dioxide and 15,000 lbs. of nitrogen oxides every year.
• The Wind Powering America program of the U.S. Dept. of Energy projects that wind power can displace 35 million tons of atmospheric carbon by year 2020.
• Wind energy takes the pressure off of natural gas demand and helps reduce natural gas prices, which helps consumers, farmers and the overall economy.
• Ethanol is a renewable, economical, environmentally-friendly, clean-burning fuel
• Ethanol from corn, other grains and biomass enhance U.S. energy security.
• The Coalition for a Renewable Fuels Standard reports that 73 ethanol facilities have the capacity to produce 2.9 billion gallons of ethanol per year;
• 14 new facilities are under construction and dozens more are being planned; Biodiesel is clean burning/provides significant reductions in EPA-targeted emissions
• In May 2000, biodiesel became the only alternative fuel to successfully complete EPA’s Tier I and Tier II testing under Section 211 (b) of the Clean Air Act.
• DOE and USDA have calculated carbon dioxide reductions of 78% for biodiesel when compared with petroleum diesel in a full life cycle analysis.
• Biodiesel reduces the compounds linked to cancer by 80-90% vs. petroleum diesel
• Biodiesel essentially has no sulfur, meeting 2006 ultra-low sulfur standard-15ppm
• Wind energy, ethanol and biodiesel can enhance farm and rural income and jobs
• USDA’s Sept. 2003 report shows only 6% of farm income comes from farming
• A 240 MW wind farm in Iowa created 200, 6-month construction jobs; 40 permanent jobs; $2 million in tax payments to counties; $640,000 in land leases
• Iowa’s electric utility customers can save $300 million over 25 years if a proposal that 10% of the state’s electric demand be met with wind energy is adopted
• One ethanol plant in Nebraska produces: 40 million gallons of ethanol; 33 full time jobs; $1.2 million in annual payroll and $1,157,600 in taxes (property/excise)
• USDA-ERS found that an average annual increase of the equivalent of 200 million gallons of soy-based biodiesel would boost crop cash receipts by $5.2 billion cumulatively by 2010, increasing net farm income by $300 million/year.
  Policy Solutions Needed NOW to Capture Benefits of Wind, Ethanol and Biodiesel
• Extend the wind energy Production Tax Credit (PTC) for multiple years
• Remove wind PTC passive requirements subject to Alternative Minimum Tax
• Adopt AWEA wind energy ‘pipeline’ concept and upgrade electric transmission
• Adoption of a Renewable Portfolio Standard (RPS) at national and state levels
• Administration request fully funded 02 Farm Bill Energy Title for the long term
• Adopt the modified Renewable Fuels Standard (RFS) agreement in the energy bill

Suggested Readings

• Comparative Air Emissions Of Wind and Other Fuels, American Wind Energy Association, Wind Energy Fact Sheet, http://www.awea.org
• Wind Powering America: Clean Energy for the 21st Century, Wind Energy Program U.S. Department of Energy, www.windpoweringamerica.gov
• Wind Energy and Economic Development: Building Sustainable Jobs and Communities, American Wind Energy Association, Wind Energy Fact Sheet, http://www.awea.org
• Concept Description: Trans-Prairie and Interior West Wind ‘Pipelines’, American Wind Energy Association, http://www.awea.org/policy/documents/WindPipeline.pdf
• 2003 Wind – National Survey of Corn Producers, American Corn Growers Foundation, http://www.acgf.org. View by clicking on Programs link.
• Estimated Economic Effects for The Prospective Fagen Ethanol Project at Central City, Nebraska, Donis N. Petersan, Ph.D., CecD, Economic Research Supervisor, Economic Development Department, Nebraska Public Power District, dnpeter@nppd.com or Todd Sneller, Adminstrator, Nebraska Ethanol Board, http://ethanol.state.ne.us or tsneller@ethanol.state.ne.us
• Impacts of Energy Efficiency and Renewable Energy on Natural Gas Markets, American Council for an Energy-Efficient Economy (ACEEE). Report commissioned by the Energy Foundation, www.ef.org
• The Energy Balance of Corn Ethanol: An Update, July 2002, by Hosein Shapouri, James A. Duffield, and Michael Wang. U.S. Department of Agriculture, Office of the Chief Economist, Office of Energy Policy and New Uses. Agricultural Economic Report No. 814. http://www.usda.gov/oce
• The Case For A Renewable Fuels Standard, Clean Fuels Development Coalition, http://www.cleanfuelsdc.org/renewables/index.html
• Biodiesel Fact Sheets-Good News For The Environment & Health, Right Now National Biodiesel Board, www.biodiesel.org/resources/fuelfactsheets
• Coalition for a Renewable Fuels Standard, September 16, 2003 letter to House and Senate Conferees in support of the Renewable Fuels Standard (RFS) during conference on H.R. 6. Transportation Investment, Renewable Fuels & Agricultural Organizations…Urge Inclusion of Grassley/Baucus Ethanol Proposal, letter to Senators in support of the Volumetric Ethanol Excise Tax Credit (VEETC) Act of 2003, S. 1548. Both letters are posted on the American Corn Growers Association website and can be viewed at http://www.acga.org by clicking on the News Views link.

Dan McGuire is the Chief Executive Officer of the American Corn Growers Foundation (ACGF). He carries out the Wealth From The Wind program to expand wind energy utilization and inform farmers and rural America about the opportunities in developing wind energy projects, both large and small. He serves on the Ag Outreach Committee of the Wind Powering America (WPA program) of the U.S. Department of Energy and National Renewable Energy Laboratory with which the ACGF partners to promote wind energy. Dan executes the ACGF Farmer Choice-Customer First information program on biotech crops and served on the first University of Pennsylvania Bioethics Panel on genetically engineered crops. He is a life member of the National Farmers Union and has been Policy Chairman of the American Corn Growers Association (ACGA) board and an international consultant on export contract supervision, quality control and farm and trade policy analysis. He owns the same Nebraska farm that’s been in the McGuire family for over 100 years and has an annual investment, management and risk position in the farm’s crop production and sales, including corn, soybeans and hay. Dan graduated from the University of Nebraska in 1976 with a BA degree in Journalism. His professional career: two years with Bozell and Jacobs, International, developing marketing plans including print, radio, television and market research and analysis; twelve years as Agency Director of the Nebraska Wheat Board administering international programs of wheat research, market development, technical assistance, market research and trade servicing plus extensive analysis of U.S. and international farm and trade policy and grain quality issues; and six years as Executive Director of the Interstate Grain Commission, a multi-state agency charged with the mission of identifying and correcting weaknesses in the U.S. grain marketing system. His career has been devoted to improving U.S. farm, trade and energy policy in the economic interest of U.S. farmers, rural residents and the nation. He has provided testimony to the Congress including the 1985, 1990, 1996 and 2002 farm bills, the U.S./Canada Free Trade Agreement and NAFTA. Dan led the national effort known as the Clean Wheat Initiative and Identity-Preserved Marketing strategy in 1987 to regain the high quality, premium European wheat market for the U.S. His export and policy work has taken him throughout Europe and to Mexico, The Philippines, Brazil, Singapore, Japan, Taiwan, Canada, Finland, Norway, Sweden and the Baltic States (arranging the first sale of identity-preserved wheat imported by the newly re-established Estonia Grain Board in 1990 following the fall of the Soviet Union). Farm and agribusiness entities today use that model of identity-preserved and quality grain marketing strategies resulting from those early customer-oriented marketing initiatives.