When I lived in Wisconsin, we said in the summer when it was humid that all that water vapor was from the corn growing in Iowa. Earth.com posted a recent story which described an ongoing experiment to look at changes in clouds due to agricultural irrigation in the Great Plains. The field experiment is called GRAINEX (Great Plains Irrigation Experiment). You might expect that adding a lot of moisture to the soil and increasing the flux of water vapor through crop growth would change precipitation and cloud patterns in the region. That is what they hope to find out through this experiment, which is collecting data through the end of July. You can read more at https://www.earth.com/news/agricultural-irrigation-cloud-formation/.
