California Fire Season

Fire is recognized as an integral part of California ecosystems. Fire seasons are complex, dynamic processes influenced by drought, hot temperatures, wildland fuels, topography, wind, ignition sources, and availability of firefighting resources. The mixture of these elements dictates what happens in a fire season. The 2015 fire season for the Shasta-Trinity and Six Rivers National Forests presented a challenging blend of these components.
Four Years of Drought
Persistent dry weather dominated much of the western U.S. making California vulnerable to an active fire season. The North Aman Drought Monitor from late June showed severe to exeptional drought in the western U.S. and Canada with California noted as one of the locations with the
Fire Danger is a description of the complex interactions of factors affecting ignition, fire spread, and difficulty of control. Two outputs of this system commonly used by fire managers are the Energy Release Component (ERC) and the Burning Index (BI).
Energy Release Component
The Energy Release Component (ERC) is a NFDRS index related to how hot a fire could burn. ERC is directly related to the 24-hour, potential worst case, total available energy (BTUs) per unit area (in square feet) within the flaming front at the head of a fire.

The ERC is a good indicator of the progression of the local fire season, as it tracks seasonal fire danger trends. ERC is a function of the fuel model (grass, brush, forested, or timber slash) and relies on live and dead fuel moistures readings. Fuel loading (weight of fuel per acre), live woody fuel moistures, and larger dead fuel moistures have an influence on the ERC. The lighter, small diameter fuels have less influence and wind speed has none. ERC has low variability, and is the best fire danger component for indicating the effects on fire behavior of intermediate to long-term
The ROSS system operates locally, regionally, nationally, and between agencies. “Unable to fill” (UTF) is a means to identify resources ordered for an incident that the dispatching system was unable to acquire.

The national wildland firefighting resource mobilization system is designed to respond to the needs of initial and extended response to wildfires. There are many factors that influence the national mobilization system’s ability to respond to the needs of the requesting unit, including anticipating requirements for new fire starts (Preparedness Levels), existing demand for resources for new and/or existing fires, or resources already committed to ongoing wildfires.

The following table summarizes the gap between resources requested and the availability of resources to fill the needs of the Fork, River, and South Complexes. Strike teams of resources are sometimes more difficult to mobilize than individual resources. Some of the UTF strike team requests may have been cancelled and then reordered as single