the physics and phenomenology of wildfire

Digital Imaging and Remote Sensing LaboratoryR.I.TRR..II..TT

The Physics andThe Physics andPhenomenology ofPhenomenology of WildfireWildfire

Bob KremensBob Kremens

SrSr. Research Scientist. Research Scientist

Digital Imaging and Remote Sensing GroupDigital Imaging and Remote Sensing Group

Center for Imaging ScienceCenter for Imaging Science

Rochester Institute of TechnologyRochester Institute of Technology

Rochester, NY, USARochester, NY, USA


Outline and Research GoalsOutl ine and Research Goals

•• We have obtained NASA funding to study the possibility of usingWe have obtained NASA funding to study the possibility of usinginexpensive satellites in LEO as fire monitors:inexpensive satellites in LEO as fire monitors:

–– Basic phenomenology of wildland f iresBasic phenomenology of wildland f ires

–– Fire scene simulation using our ray-tracing/propagation code Fire scene simulation using our ray-tracing/propagation code DIRSIGDIRSIG

–– Fire detection algorithmsFire detection algorithms

–– Satel l i te sensor and optics ‘straw man’ designsSatel l i te sensor and optics ‘straw man’ designs

•• About the Digital Imaging and Remote Sensing Group at RITAbout the Digital Imaging and Remote Sensing Group at RIT

•• Ecology, environment, resources and other motivating issuesEcology, environment, resources and other motivating issues

•• What is a wildland fire? - wildland fire behavior and flame physicsWhat is a wildland fire? - wildland fire behavior and flame physics

•• Laboratory and Field fire characterization experimentsLaboratory and Field fire characterization experiments


The Digital Imaging and Remote SensingThe Digital Imaging and Remote SensingGroup specializes in physics based remoteGroup specializes in physics based remotesensing applications and modelingsensing applications and modeling

•• Our programs use physics-based modelingOur programs use physics-based modelingand simulation to study algorithms andand simulation to study algorithms andremote-sensed phenomena.remote-sensed phenomena.

•• We acquire our own data with an airborne 70-We acquire our own data with an airborne 70-band multi-spectral imager - MISI.band multi-spectral imager - MISI.

•• We have written a physics-based ray traceWe have written a physics-based ray tracesimulator to model the scene, atmosphericsimulator to model the scene, atmospherictransmission (transmission ( MODTRANMODTRAN ) and sensor) and sensor((DIRSIGDIRSIG ).).

False Color hyperspectral image from MISI - Rochester Embayment

Piper Aztec withMISI HyperspectralImager


The remote sensing group uses a number ofThe remote sensing group uses a number ofcomputational and experimental toolscomputational and experimental tools

DIRSIG syntheticimaging simulator

MISI 80 band airbornescanning camera


Motivation for W ildland FireMotivation for W ildland FireResearchResearch


Wildfires are omnipresent in the naturalWildfires are omnipresent in the naturalenvironmentenvironment

• Fires affect the global climate throughprocesses such as trace gas and aerosolproduction, and by changes to terrestrialcarbon dynamics.

• Fires consume trees and other forestresources that may otherwise be harvested.

• Fires are a source of severe local air pollutionfor residents nearby.

• Some tree species and forest ecologiesrequire fire for health and propagation.

• Fire affects predator-prey relations as well askilling many individuals (but populations?)

• Fire has always been a part of the naturalenvironment.


Why study forest f ires?Why study forest f ires?Why build orbital f ire detectors?Why build orbital f ire detectors?

•• Correct al location of f ire f ighting resources reduces costs, minimizesCorrect al location of f ire f ighting resources reduces costs, minimizesrisk to l i fe and property.risk to l i fe and property.

•• I t is currently diff icult if not impossible to monitor wildfires accurately.It is currently diff icult if not impossible to monitor wildfires accurately.

•• Airborne systems are inadequate because of l imited coverage and shortAirborne systems are inadequate because of l imited coverage and shortloiter t ime. High-flying airborne systems (U2) are logistically difficult.loiter t ime. High-flying airborne systems (U2) are logistically difficult.

Radiation Absorbtion

4 π r2 σTe4

π a2 S 1 a( )4 π r2 σTe4

π a2 S 1 a( )4 π r2 σTe4

π a2 S 1 a( )

TeS 1 a( ).

4 σ.

1

4

Te 253.622=

Particulate matter, CO, CO2, methane,evolved water alter atmospherictransport of solar energy.

Atmospheric gaseous composition isincredibly important to energybalance - and life on Earth:

Actual average surface temperature =288 K --> +34K from greenhouseeffect


Do forest fires alter the radiation balance of theDo forest fires alter the radiation balance of theearth?earth?

•• Antarctic ice samples (and other evidence) show long term increases inAntarctic ice samples (and other evidence) show long term increases inseveral greenhouse gasesseveral greenhouse gases


Better techniques are required to detect,Better techniques are required to detect,monitor and combat wildfiresmonitor and combat wildfires

•• Current proceduresCurrent proceduresdeveloped over 75developed over 75years do not takeyears do not takeadvantage of theadvantage of thelatest technologylatest technology

•• Knowledge of f ireKnowledge of f ireposit ion and spreadposit ion and spreadrate makes resourcerate makes resourceallocation effectiveallocation effectiveand model ingand model ingpossible.possible.

•• Unusually highUnusually highspread rates causespread rates causethe majority of forestthe majority of forestfire fatalities.fire fatalities.


Forest f ires have been detected in the past byForest f ires have been detected in the past byobserving IR emissionsobserving IR emissions

•• Thermal emission spectra from 1200K f ire peaks at (Thermal emission spectra from 1200K f ire peaks at ( Wein Wein displacementdisplacementlaw):law):

λ λ λ λ = 0.29/T (cm) = 2.4 = 0.29/T (cm) = 2.4 µµµµm .m .

•• Mult i -band IR measurements al low approximate determination ofMult i -band IR measurements al low approximate determination oftemperature of scenetemperature of scene

•• Long wavelength IR (8 - 12 Long wavelength IR (8 - 12 µµµµm) can detect f ire scars and ‘hot’ ground ( i fm) can detect f ire scars and ‘hot’ ground ( i flarge enough in area)large enough in area)

•• Very large dynamic range necessary for MWIR (2.5 - 5 Very large dynamic range necessary for MWIR (2.5 - 5 µµµµm) detectors tom) detectors toavoid saturationavoid saturation

•• Likel ihood for false alarms is very high i f only one waveband is usedLikel ihood for false alarms is very high i f only one waveband is used


IR detection of fires presents difficulties whenIR detection of fires presents difficulties whenusing simple, low cost systemsusing simple, low cost systems

•• IR detectors typically not as sensit ive (on any measure) as visibleIR detectors typically not as sensit ive (on any measure) as visible(silicon) devices(silicon) devices

•• IR detectors need cooling, in general (IR detectors need cooling, in general ( bolometers bolometers a possible exception)a possible exception)

•• Small f ires may be important as precursors to larger burns and asSmall f ires may be important as precursors to larger burns and aspredictors of f ire spread.predictors of f ire spread.

•• Small f ires, which are in general sub-pixel events in a small-telescopeSmall f ires, which are in general sub-pixel events in a small-telescopesatell ite, are indistinguishable from specular reflections.satell ite, are indistinguishable from specular reflections.

•• A detector only measures the A detector only measures the total incident powertotal incident power . For a particular pixel,. For a particular pixel,in a given waveband, the same power can be obtained from a large areain a given waveband, the same power can be obtained from a large areahigh reflectivity warm surface (false alarm) or a cold background + f irehigh reflectivity warm surface (false alarm) or a cold background + f ire(‘true” alarm).(‘true” alarm).

•• Distinguishing a f ire needs a discriminating condit ion - which could beDist inguishing a f ire needs a discriminating condit ion - which could beobtained by comparison with adjacent pixels, etc.obtained by comparison with adjacent pixels, etc.

•• A large, hot f ire wil l saturate a detector designed to look at Earth-A large, hot f ire wil l saturate a detector designed to look at Earth-ambient temperatures (300K)ambient temperatures (300K)


Wildland fire is a complex physicalWildland fire is a complex physicalphenomena that demands multidisciplinaryphenomena that demands multidisciplinaryresearchresearch


W ildland Fire Behavior andW ildland Fire Behavior andPhysicsPhysics


Wildfire is a dynamic and diverse phenomenaWildfire is a dynamic and diverse phenomena


Fire converts complex hydrocarbons to simplerFire converts complex hydrocarbons to simplermolecules with the release of heat (1)molecules with the release of heat (1)

•• The combustion process (inThe combustion process (ingeneral) consists of ageneral) consists of a pyrolysispyrolysiscycle cycle and a and a soot cycle.soot cycle.

•• In the In the pyrolysispyrolysis cycle: cycle:

–– Volati le fuel compounds evaporate.Volati le fuel compounds evaporate.

–– Pyrolysis Pyrolysis (heat divided) subdivides(heat divided) subdividesfuel into 2 - 4 carbon chains.fuel into 2 - 4 carbon chains.Thermal energy comes fromThermal energy comes fromradiated heat from reaction zone.radiated heat from reaction zone.

–– 2-4 carbon chains diffuse into2-4 carbon chains diffuse intoreact ion zone and mix with oxygenreact ion zone and mix with oxygen

–– Oxidation of small HC causesOxidation of small HC causesenergy release (back-radiatedenergy release (back-radiatedenergy causes furtherenergy causes further pyrolysis pyrolysis ))


Fire converts complex hydrocarbons to simplerFire converts complex hydrocarbons to simplermolecules with the release of heat (2)molecules with the release of heat (2)

•• The combustion process (inThe combustion process (ingeneral) consists of the followinggeneral) consists of the followingsteps (soot cycle):steps (soot cycle):

–– Evaporation of volati le fuelEvaporation of volati le fuelcompoundscompounds

–– Volati le compounds aggregate intoVolati le compounds aggregate into(roughly) (roughly) spheroidal spheroidal ‘soot’‘soot’particles. Molecular weight ofparticles. Molecular weight ofthese particles is sti l l high.these particles is sti l l high.

–– Unburned soot di f fuses andUnburned soot di f fuses andcirculates throughout the f lamecirculates throughout the f lameinteriorinterior

–– With With emissivity emissivity near 1, sootnear 1, sootpart icles absorb thermal energypart icles absorb thermal energyfrom reaction zone and re-radiate.from reaction zone and re-radiate.Hot soot is responsible for theHot soot is responsible for theyel low f lame coloryel low f lame color


Wildfire begins with a pilot ignition sourceWildfire begins with a pilot ignition source

•• Ignition of duff or other fuel initiates aIgnition of duff or other fuel initiates acomplex chain of reductive reactions.complex chain of reductive reactions.

–– Earth receives 8 X 10Earth receives 8 X 1066 l ighting strikes lighting strikesper day.per day.

•• Preheating, flaming, smoldering andPreheating, flaming, smoldering andglowing combustion produce aglowing combustion produce adiversity of reaction products.diversity of reaction products.

•• Pre-ignition dehydrationPre-ignition dehydration in wildland in wildlandfuels occurs as the pilot heat driesfuels occurs as the pilot heat dries(removes) water in the fuel.(removes) water in the fuel.

•• Fuel cloud formation Fuel cloud formation follows withfollows withcontinued pilot heat. Fat,s oils,continued pilot heat. Fat,s oils,turpeneturpene , alcohol and resin molecules, alcohol and resin moleculesform a fuel cloud.form a fuel cloud.


Ignition and combustion follow application ofIgnition and combustion follow application ofpilot heatpilot heat

•• Persistent pilot heat Persistent pilot heat scorchesscorchesthe fuel, producing the fuel, producing charchar that thatemits a thick, gray emits a thick, gray tar smoke.tar smoke.(cellulose (cellulose pyrolysispyrolysis ))

•• The fuel cloud mixes withThe fuel cloud mixes withoxygen in the air and burnsoxygen in the air and burnsindependent (exothermically) ofindependent (exothermically) ofthe pilot heat.the pilot heat.

•• Radiant heat form the reactionRadiant heat form the reactionzone preheats and igniteszone preheats and ignitespreviously cool wood surfaces.previously cool wood surfaces.


The now self-sustaining process continues fromThe now self-sustaining process continues fromflaming through glowing phasesflaming through glowing phases

Flaming combust ionFlaming combust ionproduces radiantproduces radiantthermal energy whichthermal energy whichpreheats the remainingpreheats the remainingfuel. FC continues unti lfuel. FC continues unti lvolatiles volatiles are exhaustedare exhausted

After complete celluloseAfter complete cellulosepyrolysispyrolysis to char and tar, to char and tar,the fuel cloud growsthe fuel cloud growssmaller. The flame tentsmaller. The flame tentcollapses.collapses.

The collapsing reactionThe collapsing reactionzone travels to the fuelzone travels to the fueland combustionand combustioncontinues in the glowingcontinues in the glowingphase. The charphase. The char(basically C) burns with a(basically C) burns with ablue flame producing COblue flame producing CO22

and COand CO


Modeling the spread of wildfire is complexModeling the spread of wildfire is complex

•• The location and spreadThe location and spreadrate of the fire is rate of the fire is thethe most mostimportant informationimportant informationfrom a fire-fightingfrom a fire-fightingperspective.perspective.

•• Accurate models areAccurate models areavai lable (USFS FARSITE)avai lable (USFS FARSITE)but these models are onlybut these models are onlyas good as weather ,as good as weather ,terrain and fuel type inputterrain and fuel type inputdata.data.

•• Models are ‘ tweaked’Models are ‘ tweaked’dur ing run using knowndur ing run using knownposition of fire (ifposition of fire (ifavailable)available)

FARSITE fire propagation model - point sourceignition, one hour fire front contours


Fire Experiments and FieldFire Experiments and FieldData CollectionData Collection

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We have conducted laboratory experiments toWe have conducted laboratory experiments toprovide data for input to our simulationsprovide data for input to our simulations

•• We need to understand the basic physical phenomena in a fireWe need to understand the basic physical phenomena in a firethat govern the gross behaviorthat govern the gross behavior

•• We need to know what simplifications and assumptions can beWe need to know what simplifications and assumptions can bemade to ease calculations required for image synthesis andmade to ease calculations required for image synthesis andmodelingmodeling

•• We need to be able to analyze and predict the emission of narrowWe need to be able to analyze and predict the emission of narrowspectral features from wildland firesspectral features from wildland fires

•• We definitely need, at a minimum, theWe definitely need, at a minimum, the emissivity emissivity and andtemperature profiles of the flames to model a fire with temperature profiles of the flames to model a fire with DIRSIGDIRSIG

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The experiments were conducted in the combustionThe experiments were conducted in the combustionchamber at the RMSC in Missoula Montanachamber at the RMSC in Missoula Montana

•• The burn surface ofThe burn surface ofthe chamber is aboutthe chamber is about10 m square10 m square

•• The smoke stack ofThe smoke stack ofthe burn chamber isthe burn chamber isabout 40 m highabout 40 m high

•• The ‘draw’ f rom theThe ‘draw’ f rom thecombust ion chambercombust ion chamberis assisted by a 25is assisted by a 25hp fanhp fan

•In-situ instrumentation includes combustible material mass, CO2, chamber temperature•An aluminum fire bed (0.91m X 2.43m) was used. A gauge grid (0.3m) was present tojudge the location of the fire.

BryceBryceSmoke hoodSmoke hood

Burn surfaceBurn surface


Our goal was to Our goal was to extensivelyextensively characterize optical characterize opticalemissions from several emissions from several wildlandwildland fire materials fire materials

•• Make definitive spectral measurements of laboratory-conditionMake definitive spectral measurements of laboratory-conditioncontrolled fires --> controlled fires --> Wideband Wideband measurements not avai lablemeasurements not avai lable

•• Correlate narrowband spectral features with broadbandCorrelate narrowband spectral features with broadband(blackbody) features ---> (blackbody) features ---> Lit t le or no high resolut ion characterizat ionLit t le or no high resolut ion characterizat ionin v is ib le bands (1-3 nm FWHM resolut ion)in v is ib le bands (1-3 nm FWHM resolut ion)

•• DetermineDetermine emissivity emissivity of flames and the fuel bed ---> of flames and the fuel bed ---> Emissivi ty Emissivi ty notnotknown, some anecdotal in format ionknown, some anecdotal in format ion

•• Develop a shape library and/or methodology for local, detailedDevelop a shape library and/or methodology for local, detailedspatial rendering of flames --> spatial rendering of flames --> Even Hol lywood can’ t do th isEven Hol lywood can’ t do th ismodel ing!model ing!

•• Make other discoveries (alkali number density in flame,Make other discoveries (alkali number density in flame,temperature, etc.) based on quality of the data. ---> temperature, etc.) based on quality of the data. ---> ????????

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We measured a broad range of spectral andWe measured a broad range of spectral andphysical data during the experimentsphysical data during the experiments

Yellow - RIT instrumentYellow - RIT instrument

White - USFS instrumentWhite - USFS instrument

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We have one absolute and several relativeWe have one absolute and several relativespectral measurementsspectral measurements

W e m a y b eW e m a y b eable to inferable to inferemissivityemissivity ,,temperaturetemperatureand otherand otherrelevantrelevantf lameflamephysicalphysicalparametersparameters

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Across track videography measures the (visibleAcross track videography measures the (visibleand IR) spatial extent of the fire and fireand IR) spatial extent of the fire and fire‘temperature’‘temperature’

•• A Sony digital video cameraA Sony digital video cameraare used to record the visibleare used to record the visibleemissions form the fireemissions form the fire(manual exposure + ND filter)(manual exposure + ND filter)

•• An An InframetricsInframetrics-600 (FLIR)-600 (FLIR)records the IR emission in therecords the IR emission in the10-14 10-14 µµµµm wavebandm waveband

•• A Sony digital video cameraA Sony digital video camerarecords the video stream fromrecords the video stream fromthe the InframetricsInframetrics IR video IR videocamera (set to 1000K span andcamera (set to 1000K span and325K lower limit)325K lower limit) Across track videographyAcross track videography

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High-speed visible videography was acquiredHigh-speed visible videography was acquiredalong-trackalong-track

•• A JVC digital videoA JVC digital videocamera can capturecamera can capture~120 frames per~120 frames persecond in a sub-second in a sub-sampled mode.sampled mode.

•• The camera viewedThe camera viewedthe fire along-track,the fire along-track,opposite from theopposite from theASD FieldspecASD Fieldspecspectrometerspectrometer

JVC High Speed VideoJVC High Speed Video

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Across-track IR Videography is being analyzed toAcross-track IR Videography is being analyzed tomeasure cooling rates of fire ‘blobs’, measure cooling rates of fire ‘blobs’, emissivityemissivity ,,and temperature profilesand temperature profiles

•• With some assumptions aboutWith some assumptions aboutthe incandescent particulatethe incandescent particulatesmoke components, we cansmoke components, we canmeasure the cooling rate ofmeasure the cooling rate ofparticulate clumps that areparticulate clumps that areevolvedevolved

•• The volume of the f ire at anyThe volume of the f ire at anyt ime can be measuredtime can be measured

•• The size distr ibution of theThe size distr ibution of theparticulates particulates is known (C.is known (C.Hardy, D. Ward, RMRS)Hardy, D. Ward, RMRS)

•• The cool ing rate can beThe cool ing rate can bemodeled: Do we understandmodeled: Do we understandthe the emissivity emissivity and composit ionand composit ionof the particles?of the particles?

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3-Band VisibleVideography

IR (8-14 µµm)Videography


Spectrometers span the 0.35 - 10.6 Spectrometers span the 0.35 - 10.6 µµµµm wavelengthm wavelengthregimeregime

•• ASD ASD Fieldspec Fieldspec FR spectrometer:FR spectrometer:

–– 3 nm FWHM spectral resolut ion3 nm FWHM spectral resolut ion

–– 33o o field of viewfield of view

–– 0.35 - 2.5 0.35 - 2.5 µµµµm spectral rangem spectral range

•• Ocean OpticsOcean Optics

–– 0.365 nm FWHM spectral resolut ion0.365 nm FWHM spectral resolut ion

–– Spec1: 0.64 - 1.28 Spec1: 0.64 - 1.28 µµµµmm

–– Spec2: 0.18 - 0.875 Spec2: 0.18 - 0.875 µµµµmm

–– 1010 oo f ield of view field of view

•• RMRS Filter SpectrometerRMRS Filter Spectrometer

–– 6 channel: 2.44, 4.04, 5.29,7.35,10.6 6 channel: 2.44, 4.04, 5.29,7.35,10.6 µµµµmm+ + wideband wideband (0.2 - 30 (0.2 - 30 µµµµm )m )

–– 1010 oo f ield of view field of view

Stef VanGordenStef VanGorden beating the beating theASD into submissionASD into submission

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An ASD An ASD Fieldspec Fieldspec FR and an Ocean Optics D2JFR and an Ocean Optics D2Jprovided high resolution VIS-NIR spectraprovided high resolution VIS-NIR spectra

•• We have very good high resolutionWe have very good high resolutionspectra in the visible (0.3 - 0.9 spectra in the visible (0.3 - 0.9 µµµµm).m).

•• The NIR - MWIR is currently not asThe NIR - MWIR is currently not aswell understood. Are we having ASDwell understood. Are we having ASDproblems? Is the ASD capable ofproblems? Is the ASD capable ofmaking wide dynamic rangemaking wide dynamic rangeradiance measurements?radiance measurements?

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A USFS-constructed 5-channel f i l ter spectrometerA USFS-constructed 5-channel f i l ter spectrometermeasured the 2.4 - 10.6measured the 2.4 - 10.6 µµµµm emissionm emission

•• Data reduction and re-Data reduction and re-calibration in progresscalibration in progress

•• Overlaps with ASD (2.44 Overlaps with ASD (2.44 µµµµm )m )

•• Attempt to observe spectrumAttempt to observe spectrumin the LWIR to measurein the LWIR to measuredepartures from departures from PlanckianPlanckianshapeshape

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The particulate smoke and tar emit a blackbodyThe particulate smoke and tar emit a blackbodyspectrumspectrum

•• The high molecularThe high molecularweight tar componentsweight tar componentseffectively are grayeffectively are graybodies, are heated bybodies, are heated bythe radiation field fromthe radiation field fromthe combustionthe combustionprocess, and emit inprocess, and emit inthe infrared (2 - 8 the infrared (2 - 8 µµµµmmpeak)peak)

•• We have obtainedWe have obtainedreasonable estimates ofreasonable estimates ofthe packing fraction ofthe packing fraction ofthese part icles in thethese part icles in thefire bag.f ire bag.

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We have discovered very interesting narrow-We have discovered very interesting narrow-line features during wildland combustionline features during wildland combustion

We have detectedWe have detectednarrowband emissionnarrowband emissionlines from potassium,l ines from potassium,sodium andsodium andphosphorousphosphorous

These elements areThese elements aremajor constituents bymajor constituents byweight of plant fuelweight of plant fuelmaterialmaterial

The potassiumThe potassiumemission feature is veryemission feature is verystrong because of lowstrong because of lowionization potential andionization potential andhigh abundancehigh abundance

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Vegetative biomass is primarily composedVegetative biomass is primarily composedof just a few elementsof just a few elements

•• As expected, most of the mass is H,C,O and N (by weight):As expected, most of the mass is H,C,O and N (by weight):

–– C: 45%C: 45%

–– H: 5.5%H: 5.5%

–– O: 41%O: 41%

–– N: 3.5%N: 3.5%

•• But there are large (and varied) weight percentages of ‘trace’But there are large (and varied) weight percentages of ‘trace’elements:elements:

–– K: up to 7%K: up to 7%

–– NaNa : 0.1%: 0.1%

–– P: up to 1%P: up to 1%

–– Ca: up to 5%Ca: up to 5%

•• Some of these elements have unique spectral properties in a fireSome of these elements have unique spectral properties in a fire

Candidates for firedetection

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We have analyzed an AVIRIS fire data sets inWe have analyzed an AVIRIS fire data sets inseveral wavebands (several wavebands (CuiabaCuiaba , BZ), BZ)

•• Individual pixels of this data show strong potassium linesIndividual pixels of this data show strong potassium lines

•• Some IR channels saturatedSome IR channels saturated

Spectra of Fire & Background in AVIRIS Scar-B Data

0

5000

10000

15000

20000

383 837 1292 1790 2280

Wavelength (nm)

Rad

ianc

e Fire

Grass

Warm Ground

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We have analyzed an AVIRIS fire data sets inWe have analyzed an AVIRIS fire data sets inseveral wavebands (several wavebands (CuiabaCuiaba , BZ) (2), BZ) (2)

•• A - 589 nm - no smoke penetrationA - 589 nm - no smoke penetration

•• B - 770 nm - smoke penetration, bright active fire fronts visibleB - 770 nm - smoke penetration, bright active fire fronts visible

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We have analyzed an AVIRIS fire data sets inWe have analyzed an AVIRIS fire data sets inseveral wavebands (several wavebands (CuiabaCuiaba , BZ) (3), BZ) (3)

•• C - 1500 nm (smoke penetration, fire fronts)C - 1500 nm (smoke penetration, fire fronts)

•• D - Band ratio, 769 nm / 779 nm D - Band ratio, 769 nm / 779 nm thresholded thresholded to 6 to 6 σσσσ

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Very strong emission features from gaseous fireVery strong emission features from gaseous fireproducts in the VIS/NIR have been recordedproducts in the VIS/NIR have been recorded

•• Features from hot COFeatures from hot CO 22

and Hand H 22 O dominate theO dominate themolecular emissionmolecular emissionspectrum.spectrum.

•• This spectrum wasThis spectrum wasobtained from wet fuelobtained from wet fuelmaterial (Doug. Fir) in thematerial (Doug. Fir) in thesmoldering combustionsmoldering combustionphase.phase.

•• Even though theEven though theatmosphere absorbsatmosphere absorbsstrongly in these bands,strongly in these bands,the possibil i ty of ‘edgethe possibil i ty of ‘edgeeffect detection’ fromeffect detection’ fromthermal broadening isthermal broadening isexcit ing.excit ing.

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We have performed field data collections at 3We have performed field data collections at 3controlled burns in the northeastcontrolled burns in the northeast

Fort Drum

Finger Lakes Nat’lForest

Montezuma Nat’lWildlife Reguge

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We acquired spectra and ground cooling ratesWe acquired spectra and ground cooling ratesat a controlled burn at Ft. Drum (NYS)at a controlled burn at Ft. Drum (NYS)

We observed a 125 haWe observed a 125 hacontrolled burn at Fortcontrolled burn at FortDrum (Drum ( WatertownWatertown , NY), NY)

We did not We did not overflyoverflybecause of logisticsbecause of logisticsdifficulty with attackdifficulty with attackaircraft and artil leryaircraft and artil lery

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Fire fighters from Ft.Fire fighters from Ft.Drum (USA), USFSDrum (USA), USFS(GMNF and FLNF) ran(GMNF and FLNF) ranthe fire operationthe fire operation

The burn is used toThe burn is used tocontrol undergrowth tocontrol undergrowth toease troop movementsease troop movements


At a controlled burn at Finger Lake NationalAt a controlled burn at Finger Lake NationalForest, we obtained both ground and airborne-Forest, we obtained both ground and airborne-instrument datainstrument data

We used the ASDWe used the ASDspectrometer tospectrometer tomeasure spectra of themeasure spectra of thefire and reflectance offire and reflectance ofthe burn scarsthe burn scars

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The MISI The MISI hyperspectralhyperspectralcamera was camera was overflown overflown in ain aPiper Aztec at 1000,1500Piper Aztec at 1000,1500and 2500 mand 2500 m


Airborne instrument Airborne instrument overflights overflights successfullysuccessfullycaptured thermal and narrow-band fire featurescaptured thermal and narrow-band fire features

Zoom of f ire area fromZoom of f ire area fromfalse-color image. Redfalse-color image. Redpixels are high-valuepixels are high-valuepotassium emissionpotassium emission(flaming combustion)(f laming combustion)

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MISI false-color image(766 - 756 - 776 nm)

Thermal image from sameThermal image from samescene, showing hot burnscene, showing hot burnscar and combustion front.scar and combustion front.Hot gases evolved fromHot gases evolved fromcombustion are to the lowercombustion are to the lowerright.right.


Managing Forests and ForestManaging Forests and ForestFiresFires


Forest and forest f ire management hasForest and forest f ire management haschanged significantly over the last 100 yearschanged significantly over the last 100 years

•• Initial response to fires in the US was to ‘let burn’ (until 1886).Initial response to fires in the US was to ‘let burn’ (until 1886).

•• Yellowstone Park fire of 1886 was controlled by the Army.Yellowstone Park fire of 1886 was controlled by the Army.

•• US Forest Service established in 1905 by Teddy Roosevelt. US Forest Service established in 1905 by Teddy Roosevelt. GifordGifordPinchotPinchot, conservationist and forester, was first head., conservationist and forester, was first head.

–– Pinchot Pinchot establ ished a program of research, production and controlestabl ished a program of research, production and controlbased on European models of based on European models of silvaculturesilvaculture . Fire was to be . Fire was to be combattedcombattedat al l costs (a f ire is a waste of wood!)at al l costs (a f ire is a waste of wood!)

•• ‘10 AM’ established in 1920’s. CCC became part of the fire‘10 AM’ established in 1920’s. CCC became part of the firefighting workforce.fighting workforce.

•• 1940’s - some fires discovered to be beneficial to pine plantations1940’s - some fires discovered to be beneficial to pine plantationsin the South.in the South.

•• 1960’s - beneficial effects and necessity of fire became 1960’s - beneficial effects and necessity of fire became apparaentapparaent

•• 1990’s -limited ‘let burn’ policy instituted, if life and property not1990’s -limited ‘let burn’ policy instituted, if life and property notat risk.at risk.


Forest fires a battled by a complex multi-Forest fires a battled by a complex multi-faceted organizationfaceted organization

•• Depending on the size and danger of the fire, a flexible responseDepending on the size and danger of the fire, a flexible responsemay be mounted to combat the blaze.may be mounted to combat the blaze.

•• The ‘Incident Command’ hierarchy is used. This managementThe ‘Incident Command’ hierarchy is used. This managementtool is common to FEMA, armed services, and tool is common to FEMA, armed services, and NGOsNGOs

StateAgencies

Local FireDepartments

the physics and phenomenology of wildfire

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