REPORT / INTERNATIONAL NEWS

Three Iowa State researchers contributed their expertise in modeling North America's climate to a study to be published in the Journal of Geophysical Research – Atmospheres. The study – led by Sara C. Pryor, a professor of atmospheric science at Indiana University Bloomington – found that wind speeds across the country have decreased by an average of .5 percent to 1 percent per year since 1973.

"We see this trend toward slower wind speeds and our unanswered question is whether this is part of global warming or something else," one researcher said. "What we're poking into here is not something that's commonly explored. Most studies look at temperature and precipitation, not surface winds."

But the researchers said slower surface winds can have significant impacts beyond the wind power industry.

Crops, for example, depend on the wind for ventilation and cooling. Slower winds could mean higher field temperatures and less productive crops.

Slower winds could also mean more dew covering crops for longer periods, Takle said. That could mean problems with fungus and plant disease. That could also lead to lower yields at harvest time.

In cities, slower winds can mean more pollution and heat, the Iowa State researchers said.