Thinning forests are the latest indication of climate change, according to new research findings. Scientists have been exploring western forest decline.
University of Utah biology professor William Anderegg says there are threats to forests across the West, from Mexico to northern Canada. His latest focus is in Colorado forests, tracking growth rates of aspen trees in 18 separate forest plots, where he discovered tree crowns receding, which is a similar discovery in other states.
Scientists call the phenomenon "sudden aspen decline," or SAD, a form deteroriation that is spreading across forests in the West.
At its peak, in 2008, 300 square miles of forest succumbed in one year to SAD, according to researchers. SAD has been present in Arizona since 2004. Researchers say affected trees grow in the warmest (and therefore driest) parts of groves, often on the steepest inclines, where rainfall drains quickly. Researchers also call the combination of heat and reduced rainfall a “global-change-style-drought.”
