This story was originally posted by modern farmer and is republished with permission.
Hans Schmitz, an Indiana wheat farmer, made a tough decision this year. On a last-minute call, he only planted 100 acres of wheat, about half the amount of seed he usually grows. The ground no longer allowed it.
“We found it was too dry. And when we had rain just at the end of the planting window, we had problems with flooding,” he says.
Instead, Schmitz chose to plant soybeans, a less lucrative crop. “We sacrificed on the $100 per acre scale.”
Schmitz isn’t the only farmer facing climate change. So far, however, these challenges have not resulted in lower crop yields. Completely the opposite. American farmers are producing more than ever, according to USDA statistics.
The United States recorded record yields across the board in 2021 at 894 pounds per acre – a 21% increase from the previous year –according to USDA. Yields were down slightly from those record 2022 numbers, but they were still above average.
According to Ariel Ortiz-Bobea, an applied economist who studies the impact of climate change on agriculture at Cornell, agricultural production has improved in several parameters. “What you really want to know is how all the outputs increase relative to the inputs (like water and fertilizer),” he says. “It gives you a measure of your productivity.”
Even by that measure, agricultural productivity is up, Ortiz-Bobea says, citing USDA data. Agricultural production is even outpacing population growth, he says, which means farmers are still producing more than enough to feed everyone in the United States.
But researchers wonder how long these technologies and innovations can stay ahead of a warming world. A 2021 Cornell study, for example, found that farmers have lost seven years of productivity growth over the past 60 years due to climate change.
Ortiz-Bobea notes that climate change has decimated cropland in some southern parts of the planet, leading to widespread malnutrition and mass migration, and he hopes the struggles in those regions aren’t a harbinger of what’s to come in the United States as the world becomes hotter and drier.
How does climate change impact crops?
Production has trended higher in recent years, even as drought ravaged the southern sunbelt and heavy spring rains swamped fields in the Midwest. Farmers and experts attribute the increase in production to advances in farming techniques and a better understanding of how crops respond to inclement weather.
“Farmers have large, high-speed, GPS-controlled planters, and they can plant a lot of crops in a short time, even though the window for planting may be shorter,” says Fred Below, a crop physiologist and professor at the University of Illinois.
Yet, according to Below, “weather is the number one factor influencing crop yield.”
In some ways, a warming world helps farmers. Warmer weather extended planting seasons by 10 to 15 days in the Midwest. But the harmful conditions far outweigh the benefits, experts say.
“We are seeing warmer lows,” says Dennis Todey, director of the USDA Midwest Climate Hub. “Nights don’t get as cold and it looks different than if you have warmer highs during the day.” Higher night temperatures stress crops. Soybeans, for example, grow faster in warmer conditions, reducing yields.
“We are seeing warmer temperatures in February and March, and small grains such as winter wheat will grow and enter the reproductive stages earlier. Then you get a cold snap in April or May and you can see the frost damage because (the plant is) triggered to grow earlier than it should,” says Laura Lindsey, soybean and small grain agronomist with the Ohio State University Extension Service.
But one of the most difficult changes to manage is rainfall. As the climate changes, spring rains become more intense and summers experience more prolonged droughts.
Precipitation totals are increasing in some parts of the country, but rainy spells are becoming rarer — instead of 15 days with two inches of rain, areas like the Midwest could see 10 days with four inches of rain.
“One of the biggest things we’re seeing in Illinois is an increase in precipitation and precipitation intensity,” says Illinois State climatologist Trent Ford. “It’s about five inches wetter, which wouldn’t be a big deal if it was designed the right way. A lot of that happens with increasing intensity, with very large amounts of rain.”
To make matters worse, the soil can only absorb so much water and the excess erodes into nearby rivers and streams, taking expensive fertilizers with it.
“You only have a fraction of your fertilizer left for the crop,” says Ford.
Agricultural resilience
Experts note that American farmers have an advantage over growers in less developed countries because the United States has a Department of Agriculture that studies growing conditions and universities that grant land in each state, with extension services working directly with farmers. The USDA also offers monetary assistance such as crop insurance that gives farmers financial assurances.
Crops such as corn and soybeans are also being bred to use less water or to grow to a shorter height, making them less vulnerable to the intense winds that come with climate change.
“There are marker-assisted genetics in maize that confer certain water use traits,” explains below. “These contain marker-assisted genes that optimize water use.”
However, experts like Ortiz-Bobea warn that the same planting techniques that help farmers adapt now could hurt them in the future if drought proliferates. For example, corn growers plant rows of corn closer together to get the most yield from limited acres.
In some ways, this strategy works. However, when the roots are closer together, competition for scarce water intensifies, making the crop more vulnerable to drought, says Ortiz-Bobea.
How long can technology outrun the climate?
Researchers disagree on whether increased crop yields are sustainable or not, with climate change hovering over the agricultural industry like the sword of Damocles.
“Climate change is not the destroyer of agriculture in Illinois,” Ford says. “The negative impacts complicate things a bit. It changes things, and so it really requires a broad view of how we do agriculture in the Midwest and maybe we can do it more effectively in the face of these changes.
However, the data shows that a warming planet has made a difference. In a study of agricultural production last year, Cornell researchers concluded that yields would be 21% higher over the past 50 years if the weather was consistent from year to year.
And the extreme rains and prolonged drought plaguing farmers are only set to get worse.
“These really bad years are going to become more frequent,” says Ortiz-Bobea.
While some experts are hopeful, no one can say for sure that advances in science and technology will continue to offset the increasing frequency of droughts and extreme rains.
If temperature and precipitation continue to change at the rate growers have observed in recent years, global warming could eventually overwhelm farmers’ ability to adapt.
