Logic outline for evaluation of wildfire danger

The logic outline specifies how data related to wildfire danger are interpreted in NetWeaverš, a logic modeling system. The level of each primary, secondary, and elementary topic in the outline is indicated. The overall topic of the model is wildfire danger. Evaluation of overall fire danger depends directly on the evaluation of the primary topics--fire hazard, fire behavior, and ignition risk.

Logic outline for evaluation of wildfire dangera
Model topic	Primary topicb	Secondary topic	Elementary topic	Propositionc (stated in the null form)	Data inputsd
Fire danger (unione)				Danger of severe wildfire is low
	Fire hazard (union)			Fuel conditions do not support severe wildfire
		Surface fuels (union)		Condition of surface fuels is not conducive to severe wildfire
			Fire behavior fuel model	Expected fire behavior is not severe	FBFMarea, FBFMaggregation
			Fuel characterization class	Observed fuel load classes are not conducive to severe wildfire	FCCarea,  FCCaggregation
		Canopy fuels (union)		Condition of canopy fuels is not conducive to severe wildfire
			Canopy bulk density	Canopy bulk density is not conducive to severe wildfire	CBDarea, CBDaggregation
			Canopy base height	Canopy base height is not conducive to severe wildfire	CBHarea, CBHaggregation
		Fire regime condition class		Fire regime condition class is not conducive to severe wildfire	FRCCarea, FRCCaggregation
	Fire behavior (union)			Expected fire behavior associated with wildfire is relatively benign or low impact
			Spread rate	Likelihood of high spread rate of surface fire is low	spreadRate
			Flame length	Likelihood of high flame length is low	flameLength
			Fireline intensity	Likelihood of high fire line intensity is low	firelineIntensity
			Crown fire potential	Likelihood of high crown fire spread potential is low	crownfirePotential
	Ignition risk (union)			Likelihood of wildfire ignition is low
			Palmer drought severity index	Likelihood of long-term drought is low	palmerIndex
			Keetch-Byram drought index	Likelihood of short-term drought is low	keetch-byramIndex
			AVHRR NDVI	Relative plant greenness for the subwatershed is high	AVHRR-NDVI
			Lightning strike	Relative lightning strikes in the subwatershed are low	lightningStrike

a The logic outline specifies how data related to wildfire danger (see Definition of data inputs) are interpreted in NetWeaver®, a logic modeling system.

b The level of each primary, secondary, and elementary topic in the outline is indicated. The overall topic of the model is wildfire danger. Evaluation of overall fire danger depends directly on the evaluation of the primary topics--fire hazard, fire behavior, and ignition risk. Terms in parentheses following a topic indicate the logic operator used to evaluate the propositions under a topic. For example, fire danger is evaluated as the union of hazard, behavior, and ignition risk. Subtopics shown under ‘Elementary topics evaluated’ indicate the elementary topics occurring at lowest level in the logic model where data are evaluated (see Definition of data inputs).

c Each proposition evaluates a set of premises (see footnote b) or data relative to a specific landscape unit. For this analysis, subwatersheds were the landscape units.

d Definitions of data items are presented in Definition of data inputs.

e The union operator treats the premises of a proposition as factors that incrementally contribute to the proposition.

Copyright: Public Domain