What the heck is “#CornSweat” and is it making the Midwest more dangerous?

It’s pretty much just as gross as it sounds.

"In one 2020 study, researchers from the Harvard-Smithsonian Center for Astrophysics analyzed a past summer heat wave in the Midwest and found that cropland — most of which comprised corn in this part of the country — can increase moisture in the air above it by up to 40 percent."

by Benji Jones
Aug 29, 2024

"Ah, yes, late August in the Midwest: a time for popsicles by the lake, a trip to the county fair, and, of course, extreme humidity made more miserable by … corn sweat.

"Corn sweat. It’s a thing! And people are talking about it.

The term refers to the moisture released by fields of corn during hot and sunny weather. Like all other plants, corn transpires — meaning, it sucks up water from the ground and expels it into the air as a way to stay cool and distribute nutrients. Moisture also enters the air when water in the soil evaporates. Together with transpiration, this process is called #evapotranspiration.

"So, where you find loads of plants packed tightly into one place, whether the Amazon rainforest or #Iowa, humidity can skyrocket during hot and especially sunny periods, making the air feel oppressive.

"That’s what happened this week: A late-summer #heatwave brought record and near-record temperatures to parts of the Midwest where there also happen to be vast fields of corn. With plenty of sunlight and temperatures in the high 90s, it was enough to make corn sweat, producing extremely uncomfortable weather.

"It’s not that corn sweats more than other plants — an acre releases less moisture on average than, say, a large oak tree — but the Midwest has a lot of corn in late August. In Iowa, for example, more than two-thirds of the area is farmland, and corn is the top crop (followed by #soybeans, which, by the way, also sweat)."

[...]

"Again, it’s not just crops across the #Midwest that release moisture, increase humidity, and make summers feel disgusting (I know firsthand; I grew up in Iowa). The millions of acres of #prairie that industrial farmland replaced — mostly to feed livestock and make ethanol — would have also produced loads of moisture, Basso said.

"But there are some key differences between native #ecosystems and #IndustrialFarmland, he added. '#NativePrairies are diverse ecosystems with a variety of plant species, each with different root depths and water needs, helping to create a balanced moisture cycle,' he told me. 'In contrast, corn and #soy #monocultures are uniform and can draw water from the soil more quickly.'"

Read more:
https://www.vox.com/down-to-earth/369117/corn-sweat-explained-heat-wave-midwest?utm_source=pocket-newtab-en-us