Climate change could spell the end for Midwestern corn, study finds

The midwestern Corn Belt — which roughly covers parts of Indiana, Illinois, Iowa, Missouri, Nebraska and Kansas — will be “unsuitable” for cultivating corn by 2100 if climate change continues on its current trajectory, a new study finds.

“The future climate conditions … will significantly reshape biophysical suitability across the Central and Eastern U.S., causing a near collapse of corn cultivation in the Midwestern U.S. by 2100,” the study, published in Environmental Research Letters, concludes.

Using climate and soil data, Emory University environmental studies professor Emily Burchfield modeled where crops would be successfully grown in a warmer future. Burchfield found that under scenarios with high or moderate greenhouse gas emissions, the climatic conditions necessary to grow corn, soy, alfalfa and wheat will all shift notably northward, “with the Corn Belt becoming unsuitable to the cultivation of corn by 2100.”

Burchfield’s paper suggests that changes to the way crops are grown will be necessary to continue corn farming in the United States.

“These projections may be pessimistic because they don’t account for all of the ways that technology may help farmers adapt and rise to the challenge,” Burchfield said in a press release from Emory.

In fact, Midwestern farmers have already been successfully adapting to climate change. Due to a variety of technological advances, U.S. farmers today harvest more than five times as much corn per acre as farmers did 100 years ago. Some of these changes, according to a 2018 study in Proceedings of the National Academy of Sciences, have been helpful to combating rising temperatures. For example, because plants have a cooling effect on their local environment, planting closer together has reduced the effects of global warming on corn crops. Farmers also have adjusted to higher temperatures by planting crops earlier in the season and cross-breeding more with more heat-tolerant Mexican varieties of corn.

As a result, and in part because of the usual annual variation in weather, many in the Midwestern corn industry haven’t necessarily experienced any harmful impacts from climate change yet, although some note that rainfall patterns have been fairly extreme in recent years. Some U.S. farmers stopped planting corn after punishing droughts in 2007 and 2012.

“It’s hard to gauge what actually is the trend,” Taylor Moreland, owner of Moreland Seed & Soil in Centralia, Mo., told Yahoo News. “In 2012, that was a horrible drought, Midwest-wide, that was a terrible drought and there were massive losses across most farms. 2013 was kind of a drought as well. And then ’14 was awesome, ’15 was extremely wet, to the point where a lot of corn couldn’t get planted at all because if the ground is wet you can’t plant ... ’16 was another great year, ’17 was a great year, ’18 was a great year. And then, really, the past three years have been all so wet, where you typically want to plant corn in April and most farmers around here haven’t been able to plant all their corn yet this year at all, because it’s been so wet.”

But Moreland, who grew up on a farm in Missouri, pointed out that the Midwest has always seen wide fluctuations in weather.

“The weather patterns do tend to change,” he said. “If you track back before I was doing this, we had droughts, we had wet years, we had hot years. I remember my grandpa talking about this, how there were a couple years in a row where they’d have crops burn up and the family would be broke.”

To the extent that farming is given up altogether in some areas, that could actually help mitigate climate change, as former farms could, in theory, become valuable sinks for absorbing carbon dioxide from the atmosphere — but only if the land is allowed to lie fallow without being redeveloped for half a century or more, according to a new study in the journal Science Advances.

While the current Corn Belt could lose its titular crop, places like northern Minnesota and parts of Canada could become well suited to growing corn for the first time.

The Intergovernmental Panel on Climate Change has found that droughts, temperature extremes and more prevalent pests will decrease agricultural yields. The IPCC calls for swift, massive reductions in greenhouse gas emissions to avert catastrophic climate change and the widespread famine that could result.

Burchfield said that American farms will be more resilient against climate change if they switch from monoculture — a single commodity crop planted in rows — to farms that integrate more diverse crops.

“Relying on technology alone is a really risky way to approach the problem,” Burchfield said. “If we continue to push against biophysical realities, we will eventually reach ecological collapse.”