290-Unit 10 Fuel Moisture
Living fuels, Variations in live fuels, Perennial and Annual Herbaceous Vegetation, Fuel Models with live
fuels, Crown Fires.
Define critical live fuel moisture and thresholds for various fuel types
Estimation based on time of year
Live fuel sampling (oven dry method)
- (Wet-dry)/dry
Online data sources (WFAS)
3 methods for obtaining life fuel moisture
Fuel Moisture Exchange with the atmosphere
Equilibrium Moisture Content
Environmental Factors Influencing Fuel Moisture
Define the relationship between RH, wind, and moisture content of fine and large fuels.
Shaded vs unshaded (fuel temp)
Aspect (lowest FM on West)
Elevation (high=low FM)
Slope (slope % affects solar heating)
Wind (whatever is happening to fuel.. wind makes it faster)
Environmental factors influencing Fuel moisture
Precip can raise fine dead fuel moisture more rapidly.
Takes longer in large dead fuels
precipitation duration affects fine vs large differently.
-large will hold onto moisture longer, fine fuels get to saturation point then dry out quickly.
Explain how the amount and duration of precipitation and soil moisture affect moisture content of fine
and large fuels
The fuel moisture time-lag concept and its value to firefighters
Living fuels, Variations in live fuels, Perennial and Annual Herbaceous Vegetation, Fuel Models with live
fuels, Crown Fires.
Define critical live fuel moisture and thresholds for various fuel types
Estimation based on time of year
Live fuel sampling (oven dry method)
- (Wet-dry)/dry
Online data sources (WFAS)
3 methods for obtaining life fuel moisture
Fuel Moisture Exchange with the atmosphere
Equilibrium Moisture Content
Environmental Factors Influencing Fuel Moisture
Define the relationship between RH, wind, and moisture content of fine and large fuels.
Shaded vs unshaded (fuel temp)
Aspect (lowest FM on West)
Elevation (high=low FM)
Slope (slope % affects solar heating)
Wind (whatever is happening to fuel.. wind makes it faster)
Environmental factors influencing Fuel moisture
Precip can raise fine dead fuel moisture more rapidly.
Takes longer in large dead fuels
precipitation duration affects fine vs large differently.
-large will hold onto moisture longer, fine fuels get to saturation point then dry out quickly.
Explain how the amount and duration of precipitation and soil moisture affect moisture content of fine
and large fuels
The fuel moisture time-lag concept and its value to firefighters
