On the Dot: Why are wildfires becoming more extreme?

BALTIMORE -- The effects of climate change and a national policy known as "fire exclusion" are exacerbating the intensity of wildfires across the U.S., according to experts.  

In an effort to protect the nation's forests, fire exclusion aimed at suppressing all fires was implemented over a century ago. However, experts warn that these efforts have had unintended consequences.

David Schechter reports from the Bitterroot National Forest in Montana, where research ecologist Sean Parks works with the United States Forest Service. Their studies demonstrate how the buildup of fuels on the forest floor, such as small trees and dead plant material, due to fire exclusion, is contributing to the intensification of wildfires.

Parks said that indigenous tribes used to set lower intensity fires in the forest to keep the ecosystem healthy. The trees survived these fires every 10 to 30 years. However, the suppression of fire for over a century has resulted in more destructive, higher intensity fires.

"Our forests are no longer set up well to survive that inevitable fire," Parks said. "Fuels are now drier because of climate change, and when fuels are drier, the fires burn hotter, and they're harder to put out as well. That is climate change and also having more fuels on the landscape due to fire exclusion."

A shift in policy began in the 1960s, with a move towards allowing some "wildland" fire to serve its natural ecological role. 

The nexus of climate change combined with outdated national policies, the research suggests, is creating the conditions for increasingly extreme wildfires.