Fire Behavior & Weather Flashcards

What does 'fuel loading' mean and how does it affect fire behavior predictions?

Answer: The amount of combustible material per unit area, which determines the potential energy available for combustion

Fuel loading is the total dry weight of combustible material per unit area; higher fuel loads mean more energy available for release, leading to greater fire intensity.

How does a 'sea breeze' typically influence coastal wildland fire behavior during afternoon hours?

Answer: Sea breezes push fires inland in the afternoon, potentially causing rapid spread into drier interior fuels

Afternoon sea breezes blow onshore from cooler ocean water toward warmer land, potentially driving coastal fires rapidly inland into drier fuels and creating dangerous conditions.

What is 'torching' in wildland fire terminology?

Answer: An individual tree or small group of trees being engulfed in flames from bottom to top

Torching occurs when an individual tree or small cluster of trees ignites and burns intensely from base to crown, often producing firebrands that can ignite spot fires.

Which of the following best describes 'fire intensity' as a measurable fire behavior characteristic?

Answer: The rate of energy (heat) released per unit length of fire front, related to flame length

Fire intensity (fireline intensity) is the rate of heat energy released per unit length of fire front and is closely related to flame length, which firefighters use as a practical field indicator.

What role does 'continuity of fuels' play in determining whether a fire will spread?

Answer: Gaps and breaks in fuels can slow or stop fire spread by removing the pathway for flames to travel

Fuel continuity describes how connected fuels are across a landscape; significant gaps and breaks interrupt the pathway fire needs to spread from one area to another.

What weather phenomenon is associated with 'dry thunderstorms' and why are they particularly hazardous?

Answer: Thunderstorms where rain evaporates before reaching the ground, but lightning and erratic winds still occur

Dry thunderstorms (virga) produce lightning that can ignite new fires, and associated outflow winds can cause erratic, unpredictable fire behavior without providing enough rain to suppress existing fires.

How does the 'fine dead fuel moisture' reading of 3% compare to a reading of 12% in terms of fire danger?

Answer: The 3% reading indicates extreme fire danger; fine fuels at 3% moisture ignite almost instantly from a single spark

Fine dead fuel moisture at 3% represents critically dry conditions where fuels ignite from virtually any ignition source and fire spreads extremely rapidly; 12% is moderate danger.