A fire has been raging through the forests of northern Colorado for a couple weeks now, while wildfires in other western states continue to burn. The High Park fire in Colorado has spread through 55,000 acres to the west of Fort Collins. A fire in southwestern New Mexico has consumed more than 290,000 acres. Both fires were started by lightning.

Several factors, including global warming and the economy, have increased the likelihood of wildfires starting in the region, directly and indirectly, now and into the future.

Global warming is thought by various scientists to be altering the climate of the region, making it hotter and drier. Over the past 30 years, average temperatures in Colorado have risen 2°F. About 98% of Colorado is in drought, and most of the other western states are experiencing drought. For most of those states, drought is projected to persist or intensify for the next couple months.

In previous decades, winter temperatures have dipped low enough to kill sufficient number of pine bark beetles and similar pests to keep their populations in check. That hasn’t happened during this last decade. As much as 878,000 acres in Colorado have been infested by pine bark beetles in a given year, and millions of trees have died as a result.

The collapse of the U.S. housing market a few years ago cut into the demand for lumber and contributed to the economic crisis from which we are still recovering. Five years ago, prospects looked good for harvesting the beetle-killed trees for timber and fuel. That hasn’t worked out quite as well as everyone hoped. Access to the trees can be difficult, fuel prices have increased, and the profit margin has shrunk considerably.  

The fires in Colorado and other states consume considerable resources. The High Park fire has destroyed more houses than any previous fire in Colorado. Containing the fire has been costly, and recovery will require additional resources.

Fires are nature’s way of cleaning house. Dead and diseased trees are consumed and turned to ash, new growth takes over. If the fire is extremely intense, however, it can essentially sanitize an area of the seeds, plants, and trees that otherwise benefit from fire.

To reduce the potential for massive wildfires and improve the health of national forests, the U.S. Forest Service has embarked on a program of controlled burns and thinning. Even apparently sound plans can have drawbacks, however. Controlled burns have occasionally become uncontrolled, and one study suggests that thinning might actually release more carbon into the atmosphere.

Day-to-day, sound forest management practices are essential to maintaining productive forest lands and reducing the risk for and extent of forest fires. In the long-term, one of the necessary steps to improve the health of forests overall and help prevent or limit forest fires is to address global warming, without further delay.