Results of UW-Madison Study on Carbon Emissions Disputed

by Carol Spaeth-Bauer (Wisconsin State Farmer) A University of Wisconsin-Madison study released on Nov. 15 has officials in the ethanol industry frustrated, disputing the methodology of the study saying the claims of the study are not supported by fact.

The study showed a shift of more than 7 million acres into cropland that led to massive releases of carbon emissions into the atmosphere after a 2007 federal law mandated ethanol in gasoline.

The increased carbon emissions are equivalent to 20 million new cars driving down American roadways every year, according to the researchers' estimates in the study.

Findings of the study point to big changes in land use across the Midwest from 2008 to 2012 that coincided with a change in federal law that required blending ethanol from crops like corn and soybeans into gasoline.

The National Wildlife Foundation sponsored the research done by two UW-Madison graduate students, according to the Wisconsin State Journal.

Satellite images and other data to identify landscape changes over time were studied by the researchers who used computer modeling to estimate the carbon that had been stored in soil.

According to the UW-Madison study, Wisconsin ranked ninth in carbon dioxide releases during that time due to farming practices of converting pastures, forests and some wetlands to farmland.

"If the authors of the study had taken the time to get out of the classroom and into the field, they would see we are not converting wetlands, pastures or forests to produce more corn in the U.S.," Jennings said. "Farmers are adopting no-till and other practices that enable them to actually produce more bushels on the same acres."

Since the Renewable Fuel Standard (RFS) was increased by Congress, the national average yield for corn has risen from 2007 to 2017, but land use for corn production during that time has declined by nearly 4 million acres, Jennings added.

Renewable Fuels Association Executive Vice President Geoff Cooper called the release of the study "another regurgitation" of the same study released multiple times over the past several years. Cooper said those studies have been debunked and disputed.

"The authors continue to abuse and misrepresent unreliable satellite data, and they continue to present highly uncertain modeling results as if they were the gospel truth," said Cooper. “While the new study might make for a sensational headline, the facts on the ground tell a much different story about agricultural land use and the impacts of the Renewable Fuel Standard (RFS). In reality, the amount of cropland used for corn production was 3.1 million acres (3.3 percent) lower in 2017 than it was in 2007 when the RFS was expanded."

Meanwhile, farmers are producing 16 percent more corn per acre this year than in 2007, according to Cooper, providing the additional corn needed to support expansion of the ethanol industry.

"In other words, the additional corn needed to support expansion of the ethanol industry came from increased productivity on existing cropland - not from converting native grasslands into new cropland," said Cooper. "Actual empirical evidence shows that farmers have responded to increased corn demand by using existing cropland more efficiently."

According to Jennings, the latest peer-reviewed lifecycle science indicates corn ethanol approaching a "50 percent reduction in greenhouse gas emissions compared to gasoline and when the models acknowledge the way no-till corn production can increase soil carbon, that number will only get better." READ MORE