What is What is ““Fire DangerFire Danger””??

A general term used to A general term used to express an assessment of express an assessment of fixed and variable factors fixed and variable factors of the fire environment that of the fire environment that the determine the the determine the ease of ease of ignitionignition, , rate of spreadrate of spread, , difficulty of controldifficulty of control, and , and fire impactfire impact. .

from Merrill and Alexander (1987) from Merrill and Alexander (1987) CCFFM Glossary of Forest Fire Management Terms CCFFM Glossary of Forest Fire Management Terms -- 4th Edition4th Edition

Elements or Factors of Fire DangerElements or Factors of Fire Dangerto Considerto Consider

Three Components of the Fire EnvironmentThree Components of the Fire Environment

Ignition RiskIgnition Risk

What is What is ““Fire Danger RatingFire Danger Rating””??

The process of The process of systematically evaluating systematically evaluating and integrating the and integrating the individual and combined individual and combined factors influencing fire factors influencing fire danger represented in the danger represented in the form of fire danger form of fire danger indexes.indexes.

from Merrill and Alexander (1987) from Merrill and Alexander (1987) CCFFM Glossary of Forest Fire Management Terms CCFFM Glossary of Forest Fire Management Terms -- 4th Edition4th Edition

What is a What is a ““Fire Danger IndexFire Danger Index””??

A quantitative A quantitative indicator of one or indicator of one or more facets of fire more facets of fire danger, expressed danger, expressed in a relative sense in a relative sense or as an absolute or as an absolute measure. measure.

from Merrill and Alexander (1987) from Merrill and Alexander (1987) CCFFM Glossary of Forest Fire Management Terms CCFFM Glossary of Forest Fire Management Terms -- 4th Edition4th Edition

CountrymanCountryman’’s (1966) Concept of Total Fire Dangers (1966) Concept of Total Fire Danger

Why is Fire Danger Rating Needed?Why is Fire Danger Rating Needed?

Roy HeadleyRoy HeadleyDirector of Fire ControlDirector of Fire Control

U.S. Forest Service, 1919U.S. Forest Service, 1919--19411941

One of the major needs One of the major needs is for a system that will is for a system that will allow a man in charge allow a man in charge of a going fire to be less of a going fire to be less of a gambler and more of a gambler and more of a manager. of a manager.

Headley (1943) Headley (1943) ReRe--thinking Forest Fire thinking Forest Fire

ControlControl

Comparison of fire management with and without Comparison of fire management with and without the use of a fire danger rating system the use of a fire danger rating system

(from Van (from Van WilgenWilgen and Burgan 1984)and Burgan 1984)

Management using formal system Management without forManagement using formal system Management without formal systemmal system

1. Fire danger is accurately quantified 1. Fire danger is e1. Fire danger is accurately quantified 1. Fire danger is estimatedstimated

2. Fire danger can be calculated by 2. Estimations rel2. Fire danger can be calculated by 2. Estimations rely largely on y largely on newly appointed staff expernewly appointed staff experienceience

3. Use of the system will force staff to 3. No (or very fe3. Use of the system will force staff to 3. No (or very few) climatic records w) climatic records keep records of climatic data, which are keptkeep records of climatic data, which are keptare of importance to all managementare of importance to all management

proceduresprocedures

4. Management decisions are based on 4. Management decisions4. Management decisions are based on 4. Management decisions are are quantified indices and are therefore based on expequantified indices and are therefore based on experience and vary rience and vary less variable less variable greatly among individualsgreatly among individuals

I do not want to leave the impression that I think a good system of [fire] danger measurement is the answer to all fire control and management problems. It can be a guide, and a very useful one, but it can never take the place of cool, calculating, and experience judgement. –Nelson (1955)

A Panacea?A Panacea?

Ralph M. NelsonRalph M. NelsonResearcher ForesterResearcher ForesterU.S. Forest ServiceU.S. Forest Service

Southern Forest Experiment Southern Forest Experiment StationStation

Asheville, NCAsheville, NC

Applications or Uses of Applications or Uses of Fire Danger RatingsFire Danger Ratings

•• Prevention planning (e.g. informing Prevention planning (e.g. informing the public of impending fire danger, the public of impending fire danger, regulating access and risk associatedregulating access and risk associatedwith public and industrial use of forestwith public and industrial use of forestand rural areasand rural areas•• Preparedness Planning (i.e., level Preparedness Planning (i.e., level of readiness and preof readiness and pre--positioning of positioning of suppression resourcessuppression resources•• Detection Planning (e.g., lookout Detection Planning (e.g., lookout staffing and aircraft scheduling andstaffing and aircraft scheduling androutingrouting

•• Initial Attack Dispatching (e.g., Initial Attack Dispatching (e.g., prioritizing of targets for prioritizing of targets for airtankersairtankersand ground crews)and ground crews)•• Formulating suppression plans on Formulating suppression plans on active wildfires (including shortactive wildfires (including short--range range predictions of fire behavior and growth)predictions of fire behavior and growth)•• Evaluating fire behavior potential and Evaluating fire behavior potential and guidelines for safe work practices forguidelines for safe work practices forfirefightersfirefighters•• Escaped fire situation analysis Escaped fire situation analysis (including long(including long--range projections ofrange projections offire growth and behavior)fire growth and behavior)

Applications or Uses of Fire Danger RatingsApplications or Uses of Fire Danger Ratings

Applications or Uses of Fire Danger RatingsApplications or Uses of Fire Danger Ratings•• Prescribed fire planning and Prescribed fire planning and execution, including smoke execution, including smoke managementmanagement

•• Fire and fuel management Fire and fuel management modellingmodelling and planning and planning

•• Fire behavior trainingFire behavior training

•• WildlandWildland fire researchfire research

American Pioneer in Forest Fire Research:American Pioneer in Forest Fire Research:Harry T. Harry T. GisborneGisborne

First fullFirst full--time USFS fire researcher appointed in 1922time USFS fire researcher appointed in 1922

Canadian Pioneers in Canadian Pioneers in Forest Fire Research:Forest Fire Research:

James G. Wright and Herbert W. James G. Wright and Herbert W. BeallBeall

Wright initiates FDR research within the federal forest service Wright initiates FDR research within the federal forest service in in 1924. 1924. BeallBeall becomes Wrightbecomes Wright’’s summer student in 1928 and s summer student in 1928 and

obtains a fullobtains a full--time appointment in 1932.time appointment in 1932.

Australian Bushfire Research Pioneers: Australian Bushfire Research Pioneers: Alan Alan McArthurMcArthur and and Harry LukeHarry Luke

Trends in Fire Danger Rating SystemsTrends in Fire Danger Rating Systems

Origins: Local Level (starting in the early 30s)Origins: Local Level (starting in the early 30s)

Regional Level (up to the mid to late 60s)Regional Level (up to the mid to late 60s)

National Level (recognition in the late 1950s; National Level (recognition in the late 1950s; achieved beginning in the early 1970s)achieved beginning in the early 1970s)

Global Level (recognition of need as early as Global Level (recognition of need as early as the late 70s; revitalized interest in 2005)the late 70s; revitalized interest in 2005)

Historical accountsHistorical accounts

Basic Issues in Fire Danger RatingBasic Issues in Fire Danger Rating

In developing a fire danger rating In developing a fire danger rating system, the first issue is to formulate system, the first issue is to formulate objectives defining what the fire objectives defining what the fire danger rating system should be danger rating system should be designed to do. designed to do.

Once that is determined, decisions Once that is determined, decisions can be made on the six basic issues can be made on the six basic issues of developing an operating system. of developing an operating system.

Basic Issues in Fire Danger RatingBasic Issues in Fire Danger Rating

• What to measure (i.e. what factors or What to measure (i.e. what factors or elements to be measured)?elements to be measured)?•• When to measure (i.e., time of year and When to measure (i.e., time of year and time of day)?time of day)?•• Where to measure (i.e., how many points Where to measure (i.e., how many points and where should they be located0?and where should they be located0?•• How to measure (e.g., in the forest or in How to measure (e.g., in the forest or in the the ““openopen””)?)?•• How to integrate measurements (e.g., How to integrate measurements (e.g., determination of joint effects on ignition determination of joint effects on ignition and spread)?and spread)?•• How to apply danger ratings? How to apply danger ratings?

From (Brown and Davis (1973)From (Brown and Davis (1973)

Topographic CharacteristicsTopographic Characteristics::•• Slope Steepness & AspectSlope Steepness & Aspect•• ElevationElevation•• ConfigurationConfiguration•• Barriers to Fire SpreadBarriers to Fire Spread

Weather CharacteristicsWeather Characteristics::•• Wind SpeedWind Speed & Direction& Direction•• Relative HumidityRelative Humidity•• Air TemperatureAir Temperature•• Rainfall Amounts & DurationRainfall Amounts & Duration•• Cloud CloverCloud Clover•• Atmospheric InstabilityAtmospheric Instability

Fuel CharacteristicsFuel Characteristics::•• QuantityQuantity•• Moisture Moisture and and ConditionCondition•• Size & ShapeSize & Shape•• Depth/HeightDepth/Height•• Arrangement Arrangement

Fire Environment FactorsFire Environment Factors

PondersoaPondersoa pine dowelspine dowels

Basswood slatsBasswood slats

Fuel Moisture AnalogsFuel Moisture Analogs

“Large Log Study” (Idaho)

Vegetative Stage or ConditionVegetative Stage or Condition

•• Degree of curing in grasslandsDegree of curing in grasslands•• UnderstoryUnderstory and and overstoryoverstory leafleaf--out in pure out in pure hardwood stands and in hardwood stands and in mixedwoodmixedwood standsstands•• UnderstoryUnderstory leafleaf--out in pure conifer stands (i.e., out in pure conifer stands (i.e., ““green surface fuel effectgreen surface fuel effect””) )

In general, fire danger ratings determined at a basic In general, fire danger ratings determined at a basic observation time (e.g., noon LST are intended to apply observation time (e.g., noon LST are intended to apply

to the to the ““peakpeak”” burning conditionsburning conditions

Designing a fire weather or danger rating station Designing a fire weather or danger rating station network involves several considerations (e.g., network involves several considerations (e.g., fire occurrence, fuels and topography, valuesfire occurrence, fuels and topography, values--atat--stake, cost considerations). stake, cost considerations).

““OpenOpen”” exposure standard exposure standard vs. vs. ““inin--standstand”” exposureexposure

Traditional sources of data and information Traditional sources of data and information for developing fire danger rating systems:for developing fire danger rating systems:

•• Laboratory studies (e.g., fuel Laboratory studies (e.g., fuel moisture, wind and slope effects moisture, wind and slope effects on rate of fire spread)on rate of fire spread)

•• Outdoor experimental firesOutdoor experimental fires

•• Various field studies on live andVarious field studies on live anddead fuel moisturesdead fuel moistures

•• Wildfire case studiesWildfire case studies

•• Individual fire reportsIndividual fire reports

Forest fire danger rating is a Forest fire danger rating is a fascinating but exasperating fascinating but exasperating branch of forest research. branch of forest research. The goal is easily stated: The goal is easily stated: Make an index such that any Make an index such that any given index value will always given index value will always represent the same fire represent the same fire behaviourbehaviour, no matter what , no matter what weather history leads up to it. weather history leads up to it. The trouble is, one quickly The trouble is, one quickly outruns the available practical outruns the available practical knowledge and theory. A knowledge and theory. A liberal dose of philosophy is liberal dose of philosophy is required as well. required as well. –– Van Van Wagner (1970)Wagner (1970)

C.E. Van WagnerC.E. Van WagnerFire Research ScientistFire Research Scientist

Canadian Forest ServiceCanadian Forest ServicePetawawaPetawawa Forest Experiment Forest Experiment

StationStationChalk River, OntarioChalk River, Ontario

The Canadian FWI SystemThe Canadian FWI System’’s fire behavior s fire behavior indexes are patterned after indexes are patterned after Byram'sByram's (1959) (1959)

fire intensity conceptfire intensity concept

-- Initial Spread Index (ISI)Initial Spread Index (ISI)-- Buildup Index (BUI)Buildup Index (BUI)-- Fire Weather Index (FWI)Fire Weather Index (FWI)

FWI constant BUI ISI

I I = = H H ·· w w ·· rr

George M. ByramPhysicist

USDA Forest ServiceSouthern Forest

Experiment Station, Asheville, NC

KBDI Interpretation GuidelinesKBDI Interpretation Guidelines

Danger Rating Scale Danger Rating Scale ““Open endedOpen ended”” or or ““Fixed/ClosedFixed/Closed””??

Fire Danger ClassesFire Danger Classes(e.g., descriptive term and color code)(e.g., descriptive term and color code)

How many?How many?

What to call them?What to call them?

How to delineate them?How to delineate them?

Meaning?Meaning?

Delineation of Fire Danger Classes based on Actual Delineation of Fire Danger Classes based on Actual Reported Fires in South African Reported Fires in South African fynbosfynbos fuel complexesfuel complexes

(Van (Van WilgenWilgen and Burgan 1984)and Burgan 1984)

Example ofExample ofEvaluation of Fire Evaluation of Fire

Danger Class Danger Class Criteria:Criteria:

Major New Major New Zealand Exotic Zealand Exotic Pine Plantation Pine Plantation

WidlfiresWidlfires

Form of PresentationForm of PresentationUS metersUS meters

Jim Jim WrightWright’’s s

meter meter 19351935

Canada Canada Department of Department of

Forestry Forestry Early 60sEarly 60s

Canadian Forest Fire Hazard Canadian Forest Fire Hazard RecorderRecorder

Impacts of Technologies on Impacts of Technologies on Fire Danger RatingFire Danger Rating

Five General Principles of Five General Principles of Fire Danger MeasurementFire Danger Measurement

Nelson (1955)Nelson (1955)

1.1. A fairly simple method of measuring key variables A fairly simple method of measuring key variables such as fuel moisture, wind, and rain, and a way of such as fuel moisture, wind, and rain, and a way of integrating these variables into numerical values.integrating these variables into numerical values.

2. Close adherence to standards for fire weather 2. Close adherence to standards for fire weather station location and instrumentation that station location and instrumentation that established for the particular system in use.established for the particular system in use.

3. Careful training of fire weather observers.3. Careful training of fire weather observers.4. Periodic and thorough inspection of fire weather 4. Periodic and thorough inspection of fire weather

stations.stations.5. Continuity of fire weather and fire danger records. 5. Continuity of fire weather and fire danger records.

Quality control in fire danger ratingQuality control in fire danger rating

Training in fire danger ratingTraining in fire danger rating

Several key scientific, technological and human Several key scientific, technological and human elements need to be considered in the developing a elements need to be considered in the developing a

national system of fire danger ratingnational system of fire danger rating

From Taylor and Alexander (2006)From Taylor and Alexander (2006)

CFFDRS CFFDRS structure structure diagram and diagram and factors that factors that were important were important in the in the development development and and implementationimplementation

A modular system of fire A modular system of fire danger indicators or danger indicators or models of fire models of fire occurrence and behavior occurrence and behavior in important fire in important fire environments developed environments developed through a sustained through a sustained program of scientific program of scientific research and based on research and based on relationships between relationships between fire weather, fuels, fire weather, fuels, topography, and ignition topography, and ignition sources.sources.

Key Element #1Key Element #1

A reliable technical A reliable technical infrastructure to gather, infrastructure to gather, process, disseminate, process, disseminate, and archive fire weather and archive fire weather data and forecasts data and forecasts (weather (weather instruments/stations, instruments/stations, standards, standards, communications) and communications) and fire danger predictions fire danger predictions (text and map displays) (text and map displays) within operational within operational agencies. agencies.

Key Element #2Key Element #2

Guidelines, decision Guidelines, decision aids, and training for aids, and training for fire managers in the fire managers in the application of fire application of fire danger indicators danger indicators appropriate to the appropriate to the needs and capabilities needs and capabilities of operational agencies of operational agencies based on research and based on research and operational experience.operational experience.

Key Element #3Key Element #3

Cooperation between fire Cooperation between fire management agencies management agencies and with research and with research agencies to foster agencies to foster communication, to share communication, to share resources, and to set resources, and to set common standards for common standards for information, resources, information, resources, and training (policies, and training (policies, costcost--sharing agreements, sharing agreements, national training courses, national training courses, working groups). working groups).

Key Element #4Key Element #4

General Recommendation:General Recommendation:Compile Comprehensive Bibliography & Synthesis Compile Comprehensive Bibliography & Synthesis

on Fire Danger Ratingon Fire Danger Rating

FIRE DANGER RATINGFIRE DANGER RATINGPARADOXPARADOX

(after (after RothermelRothermel 1987)1987)

The systems aren't accurate enough.The systems aren't accurate enough.

The systems are too complicated.The systems are too complicated.

Presumably, crude but reliable decision Presumably, crude but reliable decision aids are needed at the field level.aids are needed at the field level.

A CautionA Caution

THANK YOU!THANK YOU!

Questions? Comments?Questions? Comments?