DURHAM, New Hampshire, November 16, 2011 A study that will be published in Nature on Thursday, Nov. 17, concludes that forests influence temperature, and their influence largely depends on latitude.
David Hollinger, a plant physiologist with the U.S. Forest Service's Northern Research Station, co-authored the article with principal investigator Xuhui Lee, a professor of meteorology at the Yale School of Forestry & Environmental Studies, and a research team that included 21 scientists from universities and research organizations in the United States, Canada, and Germany. The study was supported, in part, by grants from the U.S. Department of Energy and the Yale Climate and Energy Institute.
"Forests are complicated ecosystems with subtle climate system effects," Hollinger said. "This study underscores the need to retune climate models to reflect that complexity so we can get a better picture of the role forests play in the landscape."
Results are based on comparisons of air temperature recorded at meteorological towers located in forested areas in the United States and Canada and, as a proxy for cleared land, nearby surface weather stations operated by the National Weather Service and Environment Canada. In a review of data from Florida to Manitoba, researchers found forested land to be warmer than nearby open land north of 45 degrees latitude and cooler south of 35 degree latitude. Between 35 and 45 degrees latitude, forested and open land had similar temperatures.
North of 45 degrees, approximately the northern border of Vermont, temperatures recorded in forest interiors were warmer than temperatures recorded in open areas. This is largely because year-round night time temperatures in forests remain higher than open areas due to the mixing down of warm air aloft in forests. In addition, snow-covered open areas reflect sunlight while dark forests absorb sunlight and its warmth.
South of 45 degrees, maximum daytim
|Contact: Jane Hodgins|
USDA Forest Service - Northern Research Station