As global temperatures rise, future of agriculture uncertain

Soybean yields could decrease by as much as 40 percent due to rising temperatures. (United Soybean Board/flickr)

 Jenna Ladd | January 20, 2017

Without further action to curb greenhouse gas emissions, global temperatures are expected to rise as much as 6.1 degrees Fahrenheit above pre-industrial averages, which may meaningfully impact agricultural outputs.

According to a recent study by the the Potsdam Institute for Climate Impact Research and the University of Chicago, rising temperatures could significantly reduce U.S. grain harvests. Using a set of computer simulations, the researchers found that yield reduction could reach 40 percent for soybeans and almost 50 percent for corn by the end of the century if carbon emissions are not cut drastically. Wheat would fare slightly better, with its yields decreasing by an estimated 20 percent.

The researchers said, “The effects go far beyond the U.S., one of the largest crop exporters. World market crop prices might increase, which is an issue for food security in poor countries.”

A report by the European Union’s Joint Research Centre came to a different conclusion. They found that wheat may actually benefit from higher concentrations of carbon-dioxide in the atmosphere, while corn yields would decrease.

Although the global temperature has reached record highs for three consecutive years, U.S. corn and soybean yields were seemingly unaffected. Thanks in part to genetically modified seed, which can have adverse environmental impacts, corn and soybean output was higher than ever in 2016.

However, the extreme drought of 2012 serves as a reminder that agricultural productivity is vulnerable to a changing climate. That year, U.S. corn harvests decreased considerably and caused global corn prices to skyrocket.

Study: Climate change expected to hamper wheat yields

A wheat field in Southern Saskatchewan, Canada. (Evan Leeson/Flickr)
A wheat field in Southern Saskatchewan, Canada. (Evan Leeson/Flickr)

Nick Fetty | December 23, 2014

Rising global temperatures caused by climate change is expected to reduce wheat yields according to a recent report.

The report “Rising temperatures reduce global wheat production” was published this week in the journal Nature Climate Change. The study’s lead author is Senthold Asseng, a professor in the Department of Agricultural and Biological Engineering at the University of Florida.

The researchers found that wheat yields are expected to be reduced by 6 percent for every 1 degree Celsius the temperature rises. Estimates show that global temperatures are expected to rise between 2 and 5 degrees Celsius compared to pre-industrial levels. This temperature change and its affect on wheat harvesting is expected to have a significant impact on food demand as the world population may be as high as 12 billion by 2050.

Wheat is used to produce a wide range of goods from bread to beer and is grown in nearly every state in the country. Roughly 70 percent of wheat grown in the U.S. is used for food products, 22 percent is used for animal feed and residuals, and the remaining eight percent is used for seed.

Kansas leads the country in wheat production followed closely by North Dakota. Iowa produced 1,092,000 bushels of wheat in 2013 which amounted to less than one percent of wheat production nationwide. Wheat was the primary crop planted by early settlers in Iowa and the Hawkeye State ranked second nationwide in wheat production prior to 1870.

On the Radio: Global warming could lead to food crisis

KC McGinnis | September 15, 2014
A vegetable delivery from an Iowa community supported agriculture group. (Chanzi/Flickr)
A vegetable delivery from an Iowa community supported agriculture group. (Chanzi/Flickr)

This week’s On the Radio segment looks at a new study which suggests global warming greatly increases the odds of a global food crisis in coming decades. Listen to the audio below, or continue reading for the transcript.


Transcript: Food Crisis – Maggie St. Clair

New research from Stanford University and the National Center for Atmospheric Research suggests that climate change has greatly increased the odds of a crisis in global food production.

This is the Iowa Environmental Focus.

The study, titled “Getting caught with our plants down,” is meant to serve as a warning to institutions affected by fluctuation in food prices.

The study’s authors allow that the prospect of a major slowdown of corn and wheat production in the next few decades is low. However, they say that the chances of such of an event multiply by twenty times when global warming is factored in.

In this model, the trend of increasing food production would continue, but the rate of increase would drop substantially. This change would clash with global food demand, which is expected to keep rising.

For more information on the new study, visit

From the UI Center for Global and Regional Environmental Research, I’m Jerry Schnoor.