Climate Change and Impact on Corn and Grain Quality Eugene S. Takle Professor of Agricultural Meteorology, Department of Agronomy Professor of Atmospheric Science, Department of Geological and Atmospheric Sciences Director, Climate Science Initiative Iowa State University 49 th Annual Corn Dry Milling Conference, May 2008, Peoria, IL

Outline Comparison of natural variability of climate and humaninduced climate change Projections of future climate change Impact of climate change on “regions suitable for rain-fed agriculture”, including the US Midwest What does this mean for agriculture and cornproduction in the US Midwest?

CO 2, CH 4 and temperature records from Antarctic ice core data Source: Vimeux, F., K.M. Cuffey, and Jouzel, J., 2002, "New insights into Southern Hemisphere temperature changes from Vostok ice cores using deuterium excess correction", Earth and Planetary Science Letters, 203,

CO 2, CH 4 and temperature records from Antarctic ice core data Source: Vimeux, F., K.M. Cuffey, and Jouzel, J., 2002, "New insights into Southern Hemisphere temperature changes from Vostok ice cores using deuterium excess correction", Earth and Planetary Science Letters, 203, Natural cycles Pattern repeats about every 100,000 years

IPCC Third Assessment Report

ppm Carbon Dioxide and Temperature

ppm Carbon Dioxide and Temperature

“Business as Usual” 950 ppm Carbon Dioxide and Temperature

? “Business as Usual” 950 ppm

Source: IPCC, 2001: Climate Change 2001: The Scientific Basis

IPCC Fourth Assessment Report Summary for Policy Makers

Natural and anthropogenic contributions to global temperature change (Meehl et al., 2004). Observed values from Jones and Moberg Grey bands indicate 68% and 95% range derived from multiple simulations.

Natural cycles

Natural and anthropogenic contributions to global temperature change (Meehl et al., 2004). Observed values from Jones and Moberg Grey bands indicate 68% and 95% range derived from multiple simulations. Not Natural

Source: Jerry Meehl, National Center for Atmospheric Research

IPCC Fourth Assessment Report Summary for Policy Makers Reduced Consumption Energy intensive Energy conserving

IPCC Fourth Assessment Report Summary for Policy Makers The planet is committed to a warming over the next 50 years regardless of political decisions Energy intensive Energy conserving Reduced Consumption

IPCC Fourth Assessment Report Summary for Policy Makers Reduced Consumption Energy intensive Energy conserving Adaptation Necessary Mitigation Possible

Suitability Index for Rainfed Agriculture IPCC 2007

Suitability Index for Rainfed Agriculture IPCC 2007

Projected changes in precipitation between and for an energy- conserving scenario of greenhouse gas emissions IPCC 2007

Projected Changes* for the Climate of the Midwest Temperature *Estimated from IPCC reports

Projected Changes* for the Climate of the Midwest Precipitation *Estimated from IPCC reports

Projected Changes* for the Climate of the Midwest Other *Estimated from IPCC and CCSP reports

Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world? Bioscience 58 (3), April Freeze Event

Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world? Bioscience 58 (3), April Freeze Event

Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world? Bioscience 58 (3), April Freeze Event

Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world? Bioscience 58 (3), April Freeze Event

Gu, et al, 2008: The 2007 eastern US spring freeze: Increased cold damage in a warming world? Bioscience 58 (3), April Freeze Event

Summary Climate change since the 1970s cannot be explained onthe basis of natural variation alone (consensus) Greenhouse gases emitted from burning fossil fuelsaccount for more than half of the current warming(consensus) The warming already introduced will persist for morethan a century (consensus) Corn production will encounter some benefits andnumerous challenges (my assessment based onconsensus) The US Midwest likely will suffer less adverse effects ofclimate change than many other major rain-fedagricultural areas (my assessment based on consensus)