Alignment

Summary

Defining the fire environment means discussing how fuels, weather, and topography each possess characteristics and properties that affect fire behavior. Independently, the effect these characteristics, and properties have can be somewhat predictable. When those individual elements align with one another, the potential for extreme fire behavior may occur.

Objectives

• Describe how the primary wildland fire environment components – fuels, weather, and topography are made more complex by interaction with each other.

• Describe how alignment of these components greatly increases the potential for extreme fire behavior.

Topography-Weather: Terrain features channel winds, or cause thermal belts that keep humidity's low through the night.

Topography-Fuels: Fuels on south aspects tend to have less moisture because of solar heating. Timber on North aspects tends to be more dense and more prone to crowning. Steep drainages gather logs and other fuels that roll downhill.

Weather-Fuels: Dry weather can turn plants that are normally a barrier into available fuel. Frost-killed leaves turn from live fuel to dead fuel and can dry quickly. Trees block the wind, reducing the intensity of fires in surface fuels below them.

Alignment is when the components of fuel, weather, and topography interact, and align to create optimal conditions for extreme fire behavior.