Research forecasts Iowa corn yields could drop by half within the next half-century thanks to extreme weather.
Drought in the spring and floods in the fall, floods that would have once been considered 500 year events are now considered 100 year floods. The flooding has increased so much the drainage system of northern Iowa has nearly doubled in size in the past 30 years as the upper Midwest has grown more humid and extreme.
This drainage system is delivering massive amounts of farm fertilizer to the Mississippi River and on to the Gulf of Mexico, where the nitrate from Iowa and Illinois corn fields has grown a giant dead zone, reducing the ocean’s ability to hold carbon.
Huge rainfalls on exposed black dirt erodes the land quickly. Losing soil at two to three tons an acre a year, it can regenerate at only a half-ton a year. So the rich soil is being washed down the river four to six times faster than it can be regrown.
As the soils wash away, the crops suffer. This isn’t just in the US Midwest. In China, wheat production is falling because of degraded soil wrought by extreme weather and poor stewardship much the same as we can expect in the US’s Midwest. Overall global corn yields will decline.
Based on research at NASA, The University of Minnesota forecasts Iowa corn yields could drop in half within the next half-century because of extreme weather and soil depletion.
Kansas has resigned to drought. The high plains are locked in drought. The Ogallala Aquifer, one of the world’s largest aquifers, may be dry in as few as 20 years. Right now, its down 150 feet in Dodge City since 1950.
Farmers are taking action, starting to look into cover crops to protect the soil and hold nutrients in place during the heavy rains and floods that are more and more common. We can make agriculture resilient to a changing climate, but it will take a transformation in thinking that is not yet reflected in what is going on today.
A third of the land in the upper Midwest needs to be retired from corn and soy rotations, something major corporations in control of most agriculture can’t accept. And they happen to control the political infrastructure in these areas.
Photo: "Corn field" by Jonathan Stonehouse is licensed underCC BY 2.0