Barb Boustead recalls discovering the concept of corn sweat when she relocated to Nebraska roughly 20 years ago to work for the National Oceanic and Atmospheric Administration. It was an interesting phenomenon she encountered while being surrounded by vast fields of corn. The locals were well aware of this late-summer increase in humidity caused by corn plants cooling themselves, as Boustead, a meteorologist and climatologist, remembered.
However, this characteristic feature of Midwestern summers could be getting stickier due to climate change and the continuous expansion of industrial agriculture. Climate change is producing higher temperatures and warmer nights, allowing the atmosphere to retain more moisture. This shift has modified growing conditions, enabling farmers to plant corn further north and increasing the overall corn production in the United States.
According to the USDA’s Economic Research Service, farmers are expanding their corn acreage to meet the demand for ethanol. This expansion results in more plants working harder to regulate their temperature, which leads to the emission of humidity contributing to the steamy discomfort covering many parts of the U.S. this week.
The Midwest experiences the effects of corn sweat more prominently due to the high volume of corn grown in the region, with all plants reaching the evapotranspiration stage around the same period, creating a noticeable surge of humidity, as pointed out by Boustead.
Dennis Todey, who heads the U.S. Department of Agriculture’s Midwest Climate Hub, explained that most evapotranspiration in corn plants occurs in July rather than August. He mentioned that soybeans tend to release more vapor than corn during August.
Further research is needed to understand how climate change will impact corn sweat, with factors such as rainfall, crop variety, and farming methods playing crucial roles, according to Todey.
Lew Ziska, an associate professor of environmental health sciences at Columbia University, emphasized that warmer conditions lead to increased transpiration in plants. When asked if the rise in corn sweat is connected to climate change, Ziska straightforwardly replied, “Yes.”
Ziska also highlighted the growing demand for corn for ethanol production. A significant portion of corn cultivated in the U.S. is used to produce biofuels, which are consumed by vehicles and sometimes aircraft. Ethanol production has been steadily rising globally, except for a slight decline during the COVID-19 pandemic, as indicated by data from the Renewable Fuels Association.
The usage of ethanol also contributes to emissions that contribute to global warming.
“The fact that temperatures have been increasing should not come as a surprise. As a result of this warming trend, plants are losing more water,” Ziska stated.
Follow Melina Walling on X at @MelinaWalling.
The Associated Press’ climate and environmental coverage is supported financially by various private foundations. AP is responsible for all content. Explore AP’s guidelines for collaboration with philanthropic organizations, a list of supporters, and funded coverage areas at AP.org.
Copyright 2024 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed without permission.
