What makes wildfire wild?

Blog Post created by cathyprudhomme Employee on Oct 9, 2013

Carol's blog - Oct 13
Photo Credit:  Mike McMillan USFS (Rim Fire - Fire in the Pines)

Since the start of the year, we've posted a monthly young artists series of artwork with wildfire topics, provided by our friends with the Napa County, CA Firewise program.  This month's artwork submission was accompanied by an article authored by Carol Rice, a wildfire consultant to the Napa Firewise program.  I had concerns that the excellent information she provided might get lost amongst the artwork being highlighted, so I'm sharing it with you here today in its entirety, and I'm sure you'll agree Carol's submission is more than worthy of its own post.

When I was in graduate school my professor complained that NASA spent more that year studying small fires in space than the entire national budget on researching wildfire here at home.  He noted that a small fire inside a building (or spacecraft) was easy to explain compared with a wildfire.  It’s the  complexity of open air, uneven topography and the mix of fuels that make wildfire truly wild.

Any wildland firefighter will tell you wildfire has yet to be domesticated. Fire is like a wild animal. It can appear tame one moment, and very unpredictable and dangerous the next.

The interaction of fuels, weather and topography (the landscape) is akin to “rock-paper-scissors”—not any one dominates—but wind may be the factor that is most capricious. Terrain and wind often collude to keep fire more random. A slight topographic depression, for example, can cause the start of a fire whirlwind, a mini-tornado of fire that can consume 3 times as much fuel in any one spot.  No one can
predict when or where this phenomenon may occur.  Speaking of wild, winds also work to concentrate heat in canyons that act as chimneys. When the air arrives at the top of the ridge, eddies form on the leeward or down wind side, away from the fire like a Jacuzzi turned on its side. 

Fuel for a wildfire is never as uniform as a gas burner for a stove or a carburetor of a car. Grass, brush and forests have small gaps interspersed with areas of higher fuel densities. This makes for uneven burning, so when a fire gets a head of steam, it often surprises.

Because grasses burn so quickly, they can be more easily affected by a shift in wind direction. A short burst of wind in a different direction can send the path of fire a long way in a short time. More firefighter fatalities have occurred in light fuels than any other type of fuel.

Perhaps the most challenging aspect of wildfire is that we don’t know where or when it will occur. If we knew, we could control the environment to make it less combustible, or prevent its occurrence altogether.  Because we don’t know when a wildfire might arrive at our doorstep, the best strategy is to manage fuels so that an approaching wildfire will burn with less intensity in order to reduce damage and help with containment. In other words, because wildfire is still WILD, we need to prepare by embracing and implementing Firewise principles

 About the author: Carol Rice has consulted on fire management in the wildland-urban interface for over thirty years. She is a University of California Berkeley alumna with a Masters in fire science and management.