Most land-use change ups regional warming

COLLEGE PARK, Md., Nov. 3 (UPI) -- A new study shows most U.S. land-use changes reduce vegetative cover and raise regional surface temperatures, scientists said.

Researchers from the University of Maryland, Purdue University and the University of Colorado-Boulder said they found nearly any change that makes land cover less "green" contributes to warming. However, they said they also found conversion of any land to agricultural use results in cooling.

The scientists said their findings add significant weight to a growing recognition for the need to more fully incorporate land-use change into computer models that are designed to forecast future changes in climate conditions.

"We found that most land-use changes, especially urbanization, result in warming," said University of Maryland Professor Eugenia Kalnay, one of the study's co-authors. "A clear exception is conversion of land from other uses to agriculture, which produces relative cooling, presumably because of increased evaporation."

The study, led by Purdue University researchers Souleymane Fall and Dev Niyogi, also included Roger Pielke Sr. of the University of Colorado-Boulder.

Kalnay emphasized the findings don't negate the effects of greenhouses gases like carbon dioxide.

"I think that greenhouse warming is incredibly important, but land use should not be neglected," she said. "It clearly contributes to warming, especially in urban and arid areas."

The study is to appear later this year in the Royal Meteorological Society's International Journal of Climatology.