Using predictions from Intergovernmental Panel on Climate Change combined with crop data from 10 corn-producing states-including Indiana, researchers at Rice University in Houston and the University of California at Davis are projecting crop yield will drop 7 percent and irrigation will increase 9 percent in the next 40 years.
That may not seem like a lot, but U.C. Davis researcher Rosa Dominguez-Faus says water resources are increasingly scarce.
“We don’t know how much water we’re going to have in the future and how much water we’re going to use overall, combining all demand from other sectors,” she says.
The researchers say harvesting less corn while using more water would also likely cause the U.S. to fall short of its goals for ethanol production in coming decades.
By 2022 the country is supposed to be producing 15 billion gallons a year.
Dominguez and her colleagues have published several previous reports arguing the flaws in the U.S. ethanol policy. The group also received funding from Chevron among other sources for their research.
Purdue University agricultural economist Chris Hurt says climate change and the supply issue could be a moot point, because the ethanol mandates Congress set in 2007 do not reflect actual demand for the product.
“Congress can pass a law that says that the moon is going to move closer to the Earth,” Hurt says. “Just because Congress passes a law doesn’t mean it can be carried out.”
Gasoline suppliers will only need to blend about 13.3 billion gallons of ethanol into the gas supply this year to satisfy consumption. But by law they are supposed to 500 million gallons more – or pay penalties for falling short.
He says that, combined with the fact that demand is not likely to increase in the near future, means something in the law will have to give.
That could mean a drawdown in the ethanol mandate. If that happens, it could affect the demand Hoosier farmers are seeing for their product.
Indiana ranks about fifth in both ethanol and corn production nationwide, depending on what data is used.