A wildfire sweeps through Bitterroot National Forest in Montana. Image courtesy of John McColgan, USDA Forest Service.

Tuesday, January 05 2010 @ 04:24 PM MST Leading University of Montana researchers have released results of a new study that shows climate change will increase drought stress in northern Rocky Mountain forests, leading to increased potential for insect infestations and risk of more frequent and severe wildfires. The peer-reviewed study, conducted by UM forestry researchers, finds that longer periods of drought will stress the forest ecosystem that includes areas in Montana, Wyoming and Idaho, with increased insect epidemic and wildfire disturbances. The economic impact of highest concern is the potential of a catastrophic wildfire in the region, which could affect more than 360,000 people who live in homes in the forest-urban interface that are valued at $21 billion. “As temperatures rise, we will see about two months of additional drought stress each year by late this century,” said study author Steve Running, Regents Professor of Ecology in UM’s College of Forestry and Conservation. “And the worse global warming gets, the more significant the consequences for forests.” Key findings of the study include: * As temperatures rise, projected changes in northern Rocky Mountain forests include fewer days with snow on the ground, earlier peak snowmelt, a longer growing season and about two months of additional ecosystem drought stress each year by late this century. * Increasing drought stress will increase forest disturbances, including insect epidemics and wildfires. These disturbances have large impacts on society and the natural world. * The economic impact of highest concern is the potential for a truly catastrophic wildfire in the region. There are now 360,000 people living in homes valued at $21 billion in the forest-urban interface in this region that are directly vulnerable to wildfire. * If climate becomes drier, net carbon uptake would be reduced to the extent that most forests in the region would switch from absorbing carbon to releasing it by late this century. “Global warming will cause the spring snowmelt to occur four to six weeks earlier and the summer drought period to be six to eight weeks longer,” Running said. “By the 2080s, these dramatic shifts will leave the forests stressed and increasingly vulnerable to insect infestation and wildfire.” …

Study: Climate change means greater risk of catastrophic wildfire via The Oil Drum