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SPARKY. Lightning Fire Occurrence Prediction Model. Fire Research Network Northern Forestry Center Edmonton, Alberta. Natural Resources Canada Ressources naturelles Canada Canadian Forest Service Service canadien des for ê ts.
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SPARKY Lightning Fire Occurrence Prediction Model Fire Research Network Northern Forestry Center Edmonton, Alberta Natural Resources Canada Ressources naturelles CanadaCanadian Forest Service Service canadien des forêts
Desired Outputs of Lightning Fire Occurrence Prediction ( FOP ) Models • How many lightning fires will occur today ? • Where will the fires occur ?
Required Information for Lightning FOP • Where and When does the Lightning Strikes occur • Storm Patterns / Storm Movements • Storm Size / Storm Area • Real-time Lightning Location Systems ( LLP / LPATS / AES )
Required Information for Lightning FOP • What Type of Fuel is the Lightning Hitting • Cell-based Fuel Type Data ( FBP Fuel Associations )
Required Information for Lightning FOP • Weather Data with Weather Station Locations • Precipitation Amount and Duration ( Daily or Hourly ) • Daily FWI Calculations • What is the Weather and Moisture Contents of the Fuels
Current Research Knowledge on Lightning FOP Lightning Strikes : • 50% of All Lightning is Cloud to Ground ( CG ). • Typical storms have 5,000 CG strikes in an 8 hour period. • Large storms can have 20,000 CG strikes in a 8 hour period. • CG Strikes consists of Negative ( 90% ) and Positive ( 10%). • Within a lightning strike there can be several return strokes. • Continuous current (CC) flashes have the power to start forest fires. • Current location systems do NOT monitor CC strikes.
Current Research Knowledge on Lightning FOP Continuous Current Lightning Strikes : • LCC strikes are continuous channel discharge. • Continuous Current lightning strikes consists of : • Long Continuous Current ( LCC ) - > 40 ms • Short Continuous Current ( SCC ) - 10 - 40 ms • Questionable Continuous Current - 1 - 10 ms • 90 - 100% of Positive Strikes are LCC. • 10 - 50% of Negative Strikes are LCC ( 20% is normal ) • Percent of LCC Varies by Storm Type and Storm Size.
Current Research Knowledge on Lightning FOP To Start a Fire the LCC Strike must Hit : • Combustible Fuel with right bulk density and moisture content Combustible Fuels : • Conifer Duff and Litter Layers • Open and Protected Fuels • “Punky Wood” in snags and deep duff layer • Ignition in Protected Fuels related to : • fuel age, bulk density, organic depth and moisture content
Current Research Knowledge on Lightning FOP Racetrack Theory : • Lightning occurs over the whole racetrack area • Rainfall falls only on the infield of the racetrack Lightning Boundary Area Rain Area Storm Path The Amount of Rainfall is Related to the No. of Lightning Strikes
Ignition Survival Arrival Holdover Current Research Knowledge on Lightning FOP The Four Phases of the Lightning FOP Process :
Collecting Data Classifying the Storm Estimating Rainfall Estimating LCC Calculating % LCC Hitting Combustible Fuels Sparky - the Ignition Phase Calculating Ignitions
Sparky - the Ignition Phase Collecting the Lightning Location Data : • Break the Day into Six 4 hour periods • Period 1 - 0000 - 0400 hrs • Period 2 - 0400 - 0800 hrs • Period 3 - 0800 - 1200 hrs • Period 4 - 1200 - 1600 hrs • Period 5 - 1600 - 2000 hrs • Period 6 - 2000 - 2400 hrs • Collect Negative and Positive Lightning Data into 5 km Fop Cells Storm Classification : • For Each Period, Classify the Storm Type and Size ( 4 classes ) • For Each Period, Define the Storm Cell Classes by Fop Cells ( 5 classes ) • For Each Day-time Period, Classify Potential Catastrophic Lightning Storms • Related to Amount of Lightning in relation to FFMC / DMC values
Sparky - the Ignition Phase Defining the Type of Storm : • The Size of the Area Affected • Amount of Lightning in the Area Defining the Storm Cell Class per Fop Cell : • No. of Lightning Strikes per Cell ( 5 km ) Defines the Storm Class • Lookup Table by Storm Type • 5 Classes - Storm Edge to Storm Center Raw Lightning Data Storm Cell Definition 2 3 5 7 1 2 5 2 2 1 1 1 5 8 10 16 15 14 2 1 1 1 1 3 5 15 25 33 22 18 10 3 1 1 2 3 14 22 28 21 15 9 5 2 1 3 4 6 11 15 5 3 5 1 1 1 2 1 1 1 5 4 2 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 2 2 2 1 2 2 2 1 1 1 1 2 3 4 5 5 4 3 2 2 1 1 2 3 3 4 4 4 3 2 1 1 1 1 1 2 3 3 3 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Lookup Tableby Storm Type
Sparky - the Ignition Phase Storm Cell Definition : • Aug 3, 1994 • Period 5 ( 1600 - 2000 hrs ) • 14, 048 strikes • 5 Classes
Sparky - the Ignition Phase Estimate the Amount of Rainfall Per Fop Cell • Rainfall Amount Related to Number of Lightning Strikes in Cell • Racetrack Theory • Use Storm Cell Class Definition ( storm edge to storm center ) • Use Hourly Rainfall Data ( if available ) • Apply Algorithm that Relates Storm Class and Rainfall at Weather Station Location to Estimated Values of Rainfall by Storm Class and Apply to FOP Cell
Sparky - the Ignition Phase Rainfall Amounts Estimated from Storm Cell Class & Hourly Wxstn Data Rainfall Amount Related to Number of Lightning Strikes in Cell ( racetrack theory ) Algorithm Relates Storm Class and Rainfall at Wxstn Location to Estimated Rainfall in FOP Cell
Sparky - the Ignition Phase Estimate the Number of LCC Flashes per Fop Cell • LCC Range - 10% to 50% • Use Storm Class Definition • Use Storm Type / Size • Lookup Table Approach
Sparky - the Ignition Phase Estimate the Number of LCC Flashes Hitting Combustible Fuels • Fuel type in Cell ( Conifer - Mixedwood - Hardwood - Non-Fuel ) • Fuel Coverage in Cell - % Open Areas • Type of Fuel Complex - Open vs Protected Fuels • % Dry Areas in Open and Protected Fuels • related to Storm Cell Class, Rainfall Estimates
Sparky - the Ignition Phase Calculate the Number of Ignitions ( Firebrands ) per FOP Cell • For Open Fuels • Use Wildfire Ignition Probability Predictor ( WIPP ) • Classification of Daily Fire Danger • Based on FWI Values & Fuel Types • Probability of Sustained Ignition • For Protected Fuels • Use the Protected Ignition Probability Index ( PIPI ) • Related to Bulk Density of Fuel - varied by Region • Related to Moisture Content P = 1 / 1+ e(B0 + B1*FFMC + B2*DMC + B3*DC + B4*BUI + B5*FWI
Sparky - the Ignition Phase Calculate the Short-term Sustainability of Firebrands per FOP Cell • The Viability of Ignitions in Open and Protected Fuel Complexes is : • a function of moisture content of the fuels before the lightning storm • use FFMC / DMC / DC as indicators • use aspect of cell
# Lightning Flashes( Positive & Negative ) LCC Calculation % Dry Open % Dry Protected % Open Fuels % Protected Fuels Open Ignitions Viability Function Open Ignitions ( WIPP ) Protected Ignitions Viability Function Protected Ignitions( PIPI ) Open Ignitions and Firebrands Protected Ignitionsand Firebrands Sparky- Flowchart of the The Ignition Phase Size & Type of Storm( Racetrack Theory ) Storm Cell Definition( Proximity to Storm Center ) Rainfall Characteristics( Duration & Amount ) Fuel Type Coverage( Open & Protected Fuels )
# Lightning Flashes( Positive & Negative ) LCC Calculation % Dry Open % Dry Protected 30% 100 10.71 2 % Protected Fuels % Open Fuels 1.13 1 100 12.6 2.025 5 4.5 15.75 30 / 70 21 9 50% 30 45% 80% 55% 85% 75% Protected Ignitions Viability Function Open Ignitions Viability Function Open Ignitions ( WIPP ) Protected Ignitions( PIPI ) Open Ignitions and Firebrands Protected Ignitionsand Firebrands Sparky- the Ignition Phase - How it Works Size & Type of Storm( Racetrack Theory ) Storm Cell Definition( Proximity to Storm Center ) Rainfall Characteristics( Duration & Amount ) Fuel Type Coverage( Open & Protected Fuels )
Sparky- the Survival / Holdover Phase Estimate the Number of Firebrands Which Survive in Each Period Survival Rates Affected by : • Period of Day • Moisture Content of Fuel ( FFMC / DMC ) • Type of Fuel Complex ( Open / Protected ) SMI - Smoldering Index SMI = DC * e(-300 / (DMC)2 Survival = a * log ( SMI ) 8 Smoldering Equations
Sparky - the Arrival Phase Estimate the Number of Fire Arrivals in Present Burning Period Arrival Rates Affected by : • Period of Day ( 8 am to 8 pm ) • Moisture Content of Fuel ( FFMC / DMC ) • Type of Fuel Complex ( Open / Protected ) Arrival = a * log ( ISI ) 8 Arrival Equations
Night-Time Ignition Phase ARRIVAL Phaseof Day-Time Ignitions HOLDOVER SURVIVAL Fires SPARKY-Fire Arrival Phase Day-Time Ignition Phase Night-Time Survival Phase Arrival Phaseof Night-Time Survivals Today’s ExpectedArrivalFires ARRIVAL Phaseof Holdover Fires Day-Time SURVIVALof Non-Arrival Night-Time Fires Day-Time SURVIVAL of Non_Arrival Day-Time Fires
Desired Outputs of Lightning Fire Occurrence Prediction ( FOP ) Models • How many lightning fires will occur today ? • Where will the fires occur ?
How many lightning fires will occur today ? Sparky - Model Output ( Table ) SPARKY Fire Occurrence Prediction For August 3, 1994 ____________________________________________________ Region Lightning FOP FOP Range Holdovers Fires ____________________________________________________ Pr. Rupert 1,358 5.09 2 - 20 50.27 5 Pr. George 13,194 87.12 57 - 354 742.86 26 Vancouver 1,008 18.22 9 - 38 32.45 39 Cariboo 3,164 58.00 38 - 107 120.81 51 Kamloops 5,323 237.87 156 - 363 200.93 197 Nelson 5,422 155.15 102 - 264 215.30 120 ___________________________________________________________ Province 29,469 561.45 370 - 838 1362.61 438
Where will the fires occur ? Sparky - Model Output ( Maps ) 29, 469 Lightning Strikes Actual Fires - 438 Predicted Fires - 561 Holdovers Fires - 1362 Probability of 1+ Fires Actual Fires Locations
SPARKY Fire Occurrence Prediction ModelAnalysis of 1992 / 1993 / 1994 Data
Aug 2, 1992 • FOP Prediction 243 Fires • Actual Detections 275 Fires R2 = 0.92
Aug 6, 1993 • FOP Prediction 33 Fires • Actual Detections 41 Fires R2 = 0.95
FOP Prediction 561 Fires • Actual Detections 438 Fires Aug 3, 1994 R2 = 0.88
Sparky - The Lightning Fire Occurrence Prediction Model Strong Points of Model : • Models the trends of lightning fire occurrence. • Good for today’s LTG Arrivals and 1 Day Holdovers. • Handles small to large lightning storms. • Handles small to extreme lightning fire danger situations. • Easy to incorporate into Provincial Information Systems • ARCView compatible ( read & writes ASCII text files ) Weak Points of Model : • Holdover / Smoldering Phase ( 2+ days) • Arrivals from Holdover Phase. • Fuel Complex Definition • Parameterization for Each Province / Area
Sparky- the Lightning Fire Occurrence Prediction Model Next Step : • Installation for Operational Use in BCFS by May, 1999. • Parameterization of Model for Quebec. • Installation for Operational Use in SopFeu by June, 1999. • Investigate Possibility of Implementing in Regional Climate Model for Climate Change Projections
Wildfire Ignition Probability Prediction ( WIPPs )with Lightning Fires Overlaid for June 22, 1994
# Lightning Flashes( Positive & Negative ) LCC Calculation( Flashes with Long Continuous Current ) Precipitation Calculation Characteristics FBP Fuel Types( Type and % Coverage) Fuel Type Coverage( Open & Protected Fuels ) Sparky - The Ignition Phase Proximity to Storm Center( Five Storm Classes ) Rainfall Characteristics( Duration & Amount ) Size & Type of Storm( Racetrack Theory ) Expected #Ignitions andFirebrands Fuel Coverage Calculation Fuel Combustible Calculation Fuel Moisture Calculation( FFMC / DMC / DC ) WIPPs( Wildfire Ignition Probability Eqns )