SYMP 19-5 - Climate change impacts on agricultural systems

Thursday, August 9, 2012: 2:50 PM
Portland Blrm 251, Oregon Convention Center
Charlie Walthall, Office of National Programs, USDA Agricultural Research Service, Beltsville, MD, Jerry Hatfield, National Laboratory for Agriculture and the Environment, USDA Agricultural Research Service, Ames, IA, Laura Lengnick, Warren Wilson College and USDA Agricultural Research Service ONP, Elizabeth Marshall, USDA Economic Research Service, Peter Backlund, Integrated Science Program and External Relations, NCAR, Boulder, CO and Margaret K. Walsh, Global Change Program Office, US Department of Agriculture, Washington, DC

Agriculture in the United States is a dynamic, self-adjusting system that continually adapts to changes or fluctuations of trade, policy, markets, technology, and climate.  Recent and projected future manifestations of changing climate hold consequences for all sectors of the agricultural system.  A review of scientific literature on the impacts of climate change on agriculture and agricultural adaptation to changing climate has recently been completed. The review provides foundations for on-going risk assessments of the impacts of changing climate on agriculture and formulation of strategies for adaptation.


Water is the major challenge for agriculture with expected periods of deficiencies and excesses, decreased snowfall, and shorter, intense events.  These have consequences for selection of crops varieties, production management, allocation of water among users, and conservation measures for stewardship of soil. 

Rising air temperature, higher night time lows, extreme swings over short time periods, increasing growing season lengths, and timing of frost events present threats to production and soil resources, as well as opportunities for additional production.  Overwintering of insects, pathogens and some weeds is of concern as their management typically requires increased input costs. 

Climate impacts on livestock are directly related to the ability to maintain a body temperature within an optimum range. With the expectation of warming temperatures and increasing humidity, these trends in climate would place beef, dairy and other agricultural animals into greater risk for production.

Increasing CO2 in the atmosphere has a positive effect on some crops, including pasture species, and weeds.  Research has shown that increasing CO2 levels also decrease soil water use rates.  

There are no simple solutions for agriculture to avoid all detrimental consequences of climate change and thus informed adaptation is needed.  Greater attention to climate as criteria for decision-making is expected by future generations of producers versus that of past generations.   More sophisticated risk management via new decision-aids linking biophysical and economic models will be of interest to producers and policy-makers.  There has been an increase in crop insurance payments to producers over the past 10 years and the expectation is that these will continue to increase with the greater uncertainty of favorable growing conditions during the plant growth cycle.

Continued use of existing adaptation behavior and the development of innovative adaptation mechanisms accounting for the complex nature of agriculture as a socio-ecological system are needed.  Increasing production will require a combination of climate-ready crop varieties coupled with climate-smart production practices.