Is corn one cause of our changing our weather?

By Bev Johnson | The Daily Journal

Published Saturday, August 4, 2007

Can you believe that some climatologists are blaming the corn farmers for some of our bad weather. Corn, like all plants and many mammals, sweats. Only in plants it is called tranpiration.

An acre of corn can put 5,000 gallons of water into the air every day. Richard Raddatz, a climatologist at the University of Winnipeg has studied the change of the Canadian prairies from grassland to cropland.

He feels that there is a growing body of research indicating that contemporary crops change the way water, heat and energy interact with the atmosphere.

By transpiring more heavily than the native grasses that they replaced and in relatively short periods, crops can generate air movements that can lead to storms during the season when water is cycled through the atmosphere.

One study, done by Oklahoma climatologist Jeff Basara, traced a link between corn evaporation and an F2 tornado that hit Benson in June of 2001.

"There was going to be bad weather that day,” he said. “But evaporation added enough moisture to the atmosphere and turned it from a day of localized severe weather reports to a day that really was a headline maker."

Wayne Hallcock, whose family has farmed in Dakota County since 1912, thinks that corn may affect the weather. He now has 34,000 plants per acre.

In the 1970s, he and his father used to plant only 16,000 per acre. He found that the corn and soy beans, some of which are only 10 inches apart instead of 30 in earlier years, often are wet with dew until noon on dry days. Another climatologist, David Changnon, of Northern Illinois University, feels the 40 year trend toward higher dew points during recent heat waves, is due to changes in farming. His proof is that since 1950, crops had replaced thousands of square miles of pasture land.

Even more significant, he felt was the shift in corn planting from 40-inch rows to 30-inch rows, thus pouring more water into the air.

Not every one agrees.

Here at home, one of our climatologists, Pete Boulay, points out that in the Twin Cities, the average dew point in 3 of the last 4 summers has been below average, and much of the corn producing parts of the state are now in the second season of very dry conditions.

Of course, some of the dew points were gathered at the airport, where it is mostly paved.

Dew points at the University are higher probably because it is irrigated.

So blame sweaty corn or just ornery weather, but stay in and keep cool. Snow is coming.

This information is from an article in the Minneapolis Star Tribune. Bev Johnson is a master gardener in West Otter Tail County.