The federal government currently requires an increasing amount of ethanol and other biofuels be produced each year and blended with gasoline. Currently 39 percent of the nation's corn crop is used for ethanol, of which about one-third returns to the food system in the form of by-products fed to livestock.

But the study finds that even if temperatures stay within the internationally recognized climate change target – a limit of 3.6 degrees Fahrenheit above pre-industrial levels – global warming alone is still enough to make damaging heat waves much more common over U.S. growing regions.

"Severe heat is the big hammer," said Diffenbaugh, co-author of the study. "We find that even one or two degrees of global warming is likely to increase heat waves enough to cause much higher frequency of low-yield years, leading to greater volatility of corn prices."

One of the possible results of such price volatility could be a shift of corn growing areas further north. But the study also indicates that adverse price jumps could be neutralized by other contributing factors, like the development of drought tolerance in new corn varieties and through plant breeding programs.

Dr. Brent Bean, Texas AgriLife extension specialist, says he doubts corn production in Texas will decline in the coming years because of these reasons.

“We have seen a slow but steady increase in corn production in the state, especially in the High Plains, and while last year’s drought certainly reduced yield and overall production, there is reason to hope that new drought-tolerant varieties will help to offset any decline related to climate conditions,” he said.

Bean says corn acres in Texas may be down slightly this year as many farmers choose to plant grain sorghum because of its drought tolerance and because of an inviting sorghum market. But while cotton and sorghum remain viable crops in Texas, so does corn.

“Corn for ethanol production is largely responsible for higher corn prices in recent times. If the trend toward more corn for ethanol were to continue, the corn market would remain attractive to growers. Eventually, we may see this level out depending on what happens concerning the demand for energy crops, but I think the 15 to 18 year outlook for corn in Texas looks good and I think corn production in the state will continue to grow,” he added.

In fact, Hertel and Diffenbaugh’s study allows for increased corn acres in the U.S. if demand for corn for energy continues to be strong. In addition, the study states it is possible that plant breeding to raise the temperature threshold at which yield losses occur and increased stockholding activities by farmers and agribusinesses or changes in federal regulations could moderate the projected increases in price volatility.

Yet the study used a high-resolution climate model for the United States that takes into account climate history to produce 25-kilometer "snapshots" of the Midwest Corn Belt under projected future climate scenarios. Accordingly, five simulations from 1950 to 2040 were combined to estimate future temperature extremes. Those predictions were paired with a model that uses temperature, precipitation and technology trends to predict corn yields.

If the projections prove accurate, producers will face more periods of drought conditions in the future.