Weather Tidbits: What is “Corn Sweat”?

We’ll be discussing “corn sweat” in this edition of Weather Tidbits. Corn sweat is just a term referring to the process known as evapotranspiration. Evapotranspiration is the release of water vapor from plant leaves. All plants perform this process, but corn crops are particularly known for impacting low level humidity through its water vapor release. Even more so than the woods, mainly due to the fact that most of the vegetation and leaves are shade from the sun here. Thus, the rate of evaporation from the leaves is lower. The water vapor is released through the pores as part of their cooling and metabolic processes. In areas where corn is plentiful, large amounts of water are released into the air. This can result in rising the dewpoint to very high levels, making it feel quite uncomfortable. This is a common occurrence out in the mid-west during the summer when evapotranspiration is most active, and even here on Delmarva to an extent.