Missouri is home to 3.8 million acres of corn fields every summer. Corn, like all plants, releases water vapor into the air, which can increase humidity and make us feel more hot and humid.
“Corn sweat” is not a new term, but it has gained traction on social media over the last few years. The scientific word for corn sweat is evapotranspiration.
Missouri State Climatologist Zack Leasor said plants absorb water from the soil through their roots. That water is then transported up into the plant and eventually is released through the leaves via transpiration.
Every plant releases water vapor — even houseplants. Corn just so happens to release a lot of water vapor.
All plants release water vapor in order to cool themselves. This water vapor can impact humidity and make us feel “sticky” in summer months.
One acre of corn can release 3,000 to 4,000 gallons of water vapor into the atmosphere every day during the peak of the growing season in late July to early August. For reference, an average sized in-ground residential pool can hold about 15,000 to 30,000 gallons of water. This means 1 acre of corn releases enough water vapor to fill a swimming pool in less than a week.
The human body cools itself down in a very similar process to corn. When humans get too hot, we sweat, which is called perspiration. The water vapor from sweat evaporates and draws heat out of the body through a process called evaporative cooling.
When the air is more humid on hot days, this process is more difficult. On muggy days, sweat cannot evaporate as quickly or at all, which keeps your temperature warmer and leaves you feeling sticky.
Most of us feel the impact of corn sweat in terms of heat index temperature, or the temperature the body feels. Moisture released from corn will lead to higher dew point temperatures, and therefore more humidity.
Leasor also said there is research being done to test the connection between corn sweat and summertime thunderstorms in Missouri due to an increase in moisture.
