Good, bad effects of climate change on N. American forests cited by researchers



By Lenny Bernstein

The Washington Post

y ‘benefits,’ but the opportunities here,” said Aaron Weed, a Dartmouth postdoctoral researcher in ecology.

Researchers found 27 insects and 22 diseases that are “notable agents of disturbance” in North American forests, according to their paper, published in the journal Ecological Monographs. Some areas devastated by insects or disease may be restored because of continued warming, with insects dying off because temperatures are too high for them, Weed said.

But warming also allows insects to flourish and exaggerates their natural role in keeping forests healthy, the researchers found. Various types of bark beetles, for example, are doing more damage than expected, they said.

“It is now clear that the large extent and expanding distribution of recent outbreaks have been permitted or exacerbated by increasing temperatures during the last decades,” the paper said. “Mountain and southern pine beetles are attacking hosts farther north and at higher elevations than historic norms,” in part because warmer winters are allowing insects to survive.

In addition to insects and disease, droughts and fires also have been linked to climate change, Weed said.