They found that large wildfires became four times more frequent after 1987 and burned more than six and a half times as much forest. In essence, the region shifted that year from infrequent large wildfires that lasted roughly a week to more frequent burns that lasted for an average of more than a month. In addition, the length of the yearly wildfire season expanded by 78 days. They found that more than half of the increase in frequent large fires occurred in the northern Rockies, an area where forest management has had no impact on the natural occurrence of wildfires. In addition, large fires most commonly happened in years when snowmelt came early. “When you have a warm spring and early summer, you get earlier snowmelt,” Westerling explains. “With the snowmelt coming out a month earlier, areas then get drier earlier overall and there is a longer season in which a fire can be started. There’s more opportunity for ignition.”

News notes are courtesy of Southern Forests Network News Notes
www.southernsustainableforests.org