Results of UW-Madison study on carbon emissions disputed

Carol Spaeth-Bauer
Wisconsin State Farmer
Ethanol groups say farmers are producing more corn on fewer acres, despite what a UW-Madison study claims about cropland shift.

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

Related:Ethanol production can increase global warming, study says

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.

Land use disputed

Brian Jennings, CEO of the American Coalition for Ethanol disputes this claim.

"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. 

While the president of the National Wildlife Federation claims federal authorities are not enforcing existing requirements that prevent the conversion of non-farmland into fields of corn and soybeans, the American Coalition for Ethanol (ACE) developed a chart showing acreage data reported by farmers in South Dakota, North Dakota and Iowa. 

There has been very little variation in planted acres in these states during the last 17 years, according to this chart developed by the American Coalition for Ethanol.

"Farmers are required to report their actual planted acres of crops to FSA (Farm Service Agency) if they want to participate in government programs under the Farm Bill. That means these data points are very accurate," said Jennings. "EPA (Environmental Protection Agency) has developed what is called the aggregate compliance approach to enforce the provision of the RFS, which is intended to limit/prevent cropland expansion. Under this approach, EPA compares total cropland use to a 2007 baseline of 402 million acres and consults with USDA about land use changes. Whether or not the Wildlife Federation supports this enforcement mechanism or not, the truth is that total cropland has not expanded in the U.S. since enactment of the RFS."

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."

Ag productivity

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."

Wisconsin Biofuel Association President Erik Huschitt, agreed that farmers are producing more corn on less acreage. 

"Acreage used for growing corn is down in the United States since 2001. When you look at when ethanol started expansion in 2001, we had a significant expansion, all the way to 2017," Huschitt said. "We reduced acreage, proven by the USDA, by 325 to 318 million acres. What this study doesn’t pay respect to is productivity of the US agriculturists."

Huschitt's frustration stems from a number of different statistics available that discredit facts the UW study is claiming.

"There are really clear numbers on acreage and what dynamic is going on and the productivity that has risen over the past two decades on the American farmer," said Huschitt. 

Poor analysis

Huschitt, a proud UW-Madison alumnus, "bleeds Badger red," but he sees how the ethanol industry brought jobs to rural America, to Wisconsin, and takes personal offense to the study and poor analysis of the study.

"The UW study did an observation using satellite data and to make the claim that that’s more accurate than what is already out there is false," said Huschitt. "If they would have used USDA data or if they would have used numerous other studies done that substantiated the USDA numbers ... if this study would have actually used the numbers that are substantiated - and can’t be fuzzy math if you will - they would have came up with a different conclusion altogether."

Huschitt said when the researchers were asked about the data used in the study, they "made it clear" that there was "uncertainty in the data they were using." That should have stopped them from putting out controversial, negative information "because it's not substantiated," Huschitt pointed out.

"We would have hoped that UW would have taken a responsible approach and not used the basis of the data they are using to be so cloudy," Huschitt added. "It’s not bad to question an industry and question what’s going on, but use the facts."

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."

"When you get out from behind the desk and “ground truth” with the satellite imagery and computer-generated predictions it becomes clear that the method used by the authors of the study is not reliable," added Jennings. 

Cooper said, “The authors would be well served to step outside of the ivory towers of academia and the halls of K Street lobby shops and talk with real farmers, who understand better than anyone that conserving and improving our natural resources is in the best interest of both the agriculture industry and the American consumer.”