RNDG (RANDIG)
RANDIG is a probabilistic two-dimensional fire spread model that quantifies the relative likelihood and intensity of a fire occurring under a constant fire environment.
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For more information about the model see the Desktop Application Help Guide.
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Fire behavior calculations produced with the command line applications developed by the Missoula Fire Sciences Laboratory, Missoula, MT.
To run the RANDIG model in the FMSF, there are two required and one optional input:
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A fuelscape GeoTIFF
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An input file
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Ignition List (optional)
GeoTIFF
The RANDIG model requires a GeoTIFF landscape/fuelscape. The GeoTIFF is uploaded to the FMSF, prior to making a run request (see Upload a GeoTIFF), and the ID is used when making the model run request (see Run a Model).
The following bands must be present in the GeoTIFF in this order (additional bands may exist starting with #9):
|
Band # |
Band Name |
Units |
|---|---|---|
|
1 |
Elevation (DEM) |
meters |
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2 |
Slope |
degrees |
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3 |
Aspect |
degrees |
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4 |
Fuel Model |
categorical |
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5 |
Canopy Cover |
percent |
|
6 |
Canopy Height |
meters * 10 |
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7 |
Canopy Base Height |
meters * 10 |
|
8 |
Canopy Bulk Density |
kg/m3 * 100 |
Current cell limits for RANDIG within the FMSF is 3,000,000. If you are unsure how many cells comprise the GeoTIFF you are using to run the model, Retrieve Minimum Model Run Resolution for a GeoTIFF can be used to determine both the cell counts and the minimum resolution the model may be run.
Ignition List
When randomly placed ignitions are not desired, an ignition list can be used. This can be output from a prior run using the FIRESIZELIST switch or created by the user. To pass both an input file and an ignition list, compress the ignition list with the input file to generate a single ‘zip’ file. Then pass the ‘zip’ file to the FMSF as opposed to the single input file.
Example RANDIG input zip folder containing the input file and ignition list.
Input File
The various input and output switches included in the input file (*.txt or *.input) passed to the FMSF are documented in the following sections with the valid ranges for each switch.
Example RANDIG input file including all the input and output switches.
Initial Fuel Moisture Switches
FUEL_MOISTURES_DATA: 3
0 3 5 7 57 85
121 4 6 8 62 88
163 2 5 7 65 95
FUEL_MOISTURES_DATA: X where X is the number of initial fuel moisture data entries. Immediately following this line should be X lines of initial fuel moisture inputs.
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Valid range: 1-59
Initial fuel moisture entries must include the following six integers in order per line, space, or tab delimited:
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Fuel model number
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0 is required, this is the default moistures to use when a fuel model is encountered that does not have an entry in the input file
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Valid range: 0, 1-13, 101-109, 121-124, 141-149, 161-165, 181-189, 201-204
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1-hr dead fuel moisture content percent
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Valid range: 2-300
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10-hr dead fuel moisture content percent
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Valid range: 2-300
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100-hr dead fuel moisture content percent
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Valid range: 2-300
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Live herbaceous fuel moisture content percent
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Valid range: 2-300
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Live woody fuel moisture content percent
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Valid range: 2-300
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Wind Switches
WIND_SPEED: 3
WIND_DIRECTION: 290
SPREAD_DIRECTION_FROM_MAX: 0
GRIDDED_WINDS_GENERATE: Yes
GRIDDED_WINDS_RESOLUTION: 120
WIND_SPEED: X where X is the wind speed (mph).
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Valid range: 0-100
WIND_DIRECTION: X where X is the azimuth of the wind direction, plus uphill and downhill.
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Valid range: 0-360, -1 (uphill), -2 (downhill)
DEFAULT_UPHILL_DOWNHILL_DIRECTION: X where X is the azimuth of the wind direction.
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NOTE: This is required when WIND_DIRECTION: is -1 or -2, it is used to define the wind direction when the landscape is flat.
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Valid range: 0-360
SPREAD_DIRECTION_FROM_MAX: X where X represents the relative spread direction (azimuth) from the maximum.
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Valid range: 0-360
GRIDDED_WINDS_GENERATE: val where val is ‘Yes’ for generate gridded winds or ‘No’ for do not generate.
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NOTE: Gridded winds are calculated using the WindNinja model embedded within RNDG.
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NOTE: This switch will be ignored if the GRIDDED_WINDS_RESOLUTION is not present.
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Valid range: Yes, No
GRIDDED_WINDS_RESOLUTION: X where X is the desired resolution for the gridded winds in meters.
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NOTE: WindNinja requires a large amount of memory to run. To ensure runs are completed in a reasonable timeframe, the FMSF will adjust the GRIDDED_WINDS_RESOLUTION as needed. Initially, this adjustment will be 2 times the GeoTIFF landscape/fuelscape resolution. Subsequent FMSF adjustments to GRIDDED_WINDS_RESOLUTION may be required to keep the WindNinja grid below 1 million pixels. The GRIDDED_WINDS_RESOLUTION used to run the model can be found in the run metadata and in the input file returned when downloading the model outputs.
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Valid range: 30-10000
Canopy Characteristic Switches
FOLIAR_MOISTURE_CONTENT: 100
CROWN_FIRE_METHOD: Finney
FOLIAR_MOISTURE_CONTENT: X where X is the fuel moisture content in percent.
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Valid range: 2-200
CROWN_FIRE_METHOD: cfmethod where cfmethod is either ‘ScottReinhardt’ or ‘Finney’.
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Valid range: ScottReinhardt, Finney
Dead Fuel Moisture Conditioning Switches (Optional)
Conditioning dead fuel moistures is optional for FlamMap. When used, the following switches need to be present in the input file.
CONDITIONING_PERIOD_START: 06 04 1300
CONDITIONING_PERIOD_END: 06 13 1700
RAWS_ELEVATION: 6119
RAWS: 384
2012 6 4 0000 71 19 0.00 0 0 0
2012 6 4 0100 68 20 0.00 0 0 0
2012 6 4 0200 66 21 0.00 0 0 0
2012 6 4 0300 64 22 0.00 0 0 0
2012 6 4 0400 62 23 0.00 0 0 0
2012 6 4 0500 61 23 0.00 0 0 0
. . .
2012 6 19 2300 69 19 0.00 0 0 0
CONDITIONING_PERIOD_START: date/time where the date/time is the month, day, and military time (space delimited) for the start of the conditioning period. This is an optional input, if it is not supplied conditioning will start at the date/time of the first record following the RAWS switch.
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Valid range: MM = 1-12, DD = 1-31, HHRR = 0000-2400 (valid times within that range)
CONDITIONING_PERIOD_END: date/time where the date/time is the month, day, and military time (space delimited) for the end of the conditioning period.
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Valid range: MM = 1-12, DD = 1-31, HHRR = 0000-2400 (valid times within that range)
RAWS_ELEVATION: X where X is the elevation in feet of the RAWS (Remote Access Weather Station).
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Valid range: -1000-20000
RAWS: X where X is the number of sequential hourly weather data entries. Immediately following this line should be X lines of weather inputs.
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Valid range: >=1
Weather data entries must include the following 10 in order per line, space, or tab delimited:
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Year in the YYYY format.
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Valid range: Any
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Month in the M or MM format.
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Valid range: 1-12
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Day in the DD format.
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Valid range: 1-31
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Time of day (military) in HHMM format.
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Valid range: 0000-2400 (valid times within that range)
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Temperature in Fahrenheit at the time of the record.
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Valid range: -50-150
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Relative humidity as percent at the time of the record.
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Valid range: 0-100
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Hourly precipitation total for the hour ending at the time of the record in inches.
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Valid range: 0.00-10.00
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20 ft wind speed in MPH at the time of the record.
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Valid range: 0-150
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Azimuth of the 20 ft wind at the time of the record.
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Valid range: 0-360
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Cloud cover as percentage at the time of the record in percent.
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Valid range: 0-100
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Spotting Switches
SPOTPROBABILITY: 0.05
MTT_SPOT_DELAY: 15
SPOTTING_SEED: 1621
SPOTPROBABILITY: X where X is the probability that a spot causes an ignition.
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Valid range: 0-1
MTT_SPOT_DELAY: X where X is the number of minutes to delay an ignition caused by spotting.
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NOTE if MTT_SPOT_PROBABILITY is 0, this switch is not needed and will be ignored.
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Valid range: 0-60
SPOTTING_SEED: X where X is typically a randomly generated value; however, it can be specified in the input file.
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NOTE if MTT_SPOT_PROBABILITY is 0, this switch is not needed and will be ignored.
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NOTE if MTT_SPOT_PROBABILITY is >0, this switch is an optional input.
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Valid range: 0-999999
Simulation Time Switch
DURATION: 600
DURATION: X where X is the simulation duration for each fire in minutes.
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Valid range: 60-1440
Fires to Simulate Switches
Setting the number of fires to simulate can be competed several ways in RANDIG. A set number of random ignitions can be passed. A target proportion of burnable cells to be burned by random ignitions. Or a fire size list, from a previous run can be used to replicate the locations of fires. When this is desired, the fire size list is placed in a zip folder with the input file to be passed to the FMSF. Or fires are randomly generated based on a set number specified or a target proportion to be burned.
NUMFIRES: 0
TARGETBURNPROPORTION: 0.95
MINIMUMNUMBERFIRES: 1000
NUMFIRES: X where X is an integer representing the desired number of fires.
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NOTE: 0 is the same as this switch not being set.
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Valid range: 0-5000000
TARGETBURNPROPORTION: X where X is the proportion of the landscape the model attempts to bur with at least one fire.
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NOTE: 0 is the same as this switch not being set.
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Valid range: 0-0.98
MINIMUMNUMBERFIRES: X where X is the minimum number of fires to simulate when the TARGETBURNPROPORTION switch is used and is >0.5.
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NOTE: This switch optional
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Valid range: 1-10000
To summarize:
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Either a Fire Size List needs to be passed with the input file in a single zip folder, or NUMFIRES or TARGETBURNPROPORTION must be >0.
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If Fire Size List is passed, NUMFIRES and TARGETBURNPROPORTION should not be included if present have a value of 0. An error will be returned if the value is >0, unless NUMFIRES is identical to the number of fires within the Fire Size List.
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If NUMFIRES and TARGETBURNPROPORTION are both set to values greater than 0, whichever results in fewer fires being simulated will occur.
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If NUMFIRES is not passed (or set to 0) and a non-zero TARGETBURNPROPORTION is provided, NUMFIRES will be calculated and will always be set to a value greater than or equal to the MINIMUMNUMBERFIRES. One caveat to this is that MINIMUMNUMBERFIRES is only used when the TARGETBURNPROPORTION is greater than 50 percent.
Output Switches
RANDIG_BURN_PROBABILITY:
RANDIG_CONDITIONAL_FLAMELENGTH:
RANDIGPERIMETERS:
FLAMELENGTH:
CROWNSTATE:
The RANDIG fire behavior model will produce up to eight gridded output layers as well as three shapefiles. In addition, the full suite of FlamMap outputs are available for a RANDIG model run.
Outputs are requested by using the appropriate switch(s) in the input file (see the table for details). The order the switch(s) are listed in the input file correlate to the band order in the output GeoTIFF.
Grid outputs (part of the multi-band GeoTIFF)
|
Switch |
Output Layer |
Units |
Requires Gridded Winds |
Requires Conditioning |
|---|---|---|---|---|
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RANDIG_BURN_PROBABILITY: |
Burn Probability |
probability |
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RANDIG_FLP_CLASS_0_2: |
Proportion of Flame Lengths 0-2 ft |
probability |
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RANDIG_FLP_CLASS_2_4: |
Proportion of Flame Lengths 2-4 ft |
probability |
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RANDIG_FLP_CLASS_4_6: |
Proportion of Flame Lengths 4-6 ft |
probability |
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RANDIG_FLP_CLASS_6_8: |
Proportion of Flame Lengths 6-8 ft |
probability |
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RANDIG_FLP_CLASS_8_12: |
Proportion of Flame Lengths 8-12 ft |
probability |
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RANDIG_FLP_CLASS_12: |
Proportion of Flame Lengths > 12 ft |
probability |
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RANDIG_CONDITIONAL_FLAMELENGTH: |
Conditional Flame Length |
feet |
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FLAMELENGTH: |
Flame Length |
meters |
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SPREADRATE: |
Rate of Spread |
m/min |
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INTENSITY: |
Fireline Intensity |
kW/m |
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HEATAREA: |
Heat per Unit Area |
kJ/m2 |
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CROWNSTATE: |
Crown Fire Activity |
class* |
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SOLARRADIATION: |
Solar Radiation |
W/m2 |
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Yes |
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FUELMOISTURE1: |
1 Hr Fuel Moisture |
percent |
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Yes |
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FUELMOISTURE10: |
10 Hr Fuel Moisture |
percent |
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Yes |
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FUELMOISTURE100: |
100 Hr Fuel Moisture |
percent |
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Yes |
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FUELMOISTURE1000: |
1000 Hr Fuel Moisture |
percent |
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Yes |
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MIDFLAME: |
Mid-Flame Wind Speed |
mph |
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HORIZRATE: |
Horizontal Rate of Spread |
m/min |
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MAXSPREADDIR: |
Max Spread Direction |
degrees |
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ELLIPSEDIM_A: |
Ellipse Dim A |
m/min |
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ELLIPSEDIM_B: |
Ellipse Dim B |
m/min |
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ELLIPSEDIM_C: |
Ellipse Dim C |
m/min |
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MAXSPOT: |
Maximum Spotting |
meters |
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CROWNFRACTIONBURNED: |
Crown Fraction Burned |
percent |
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MAXSPOT_DIR: |
Spotting Direction |
degrees |
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MAXSPOT_DX: |
Spotting Distance |
meters |
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WINDDIRGRID: |
Wind Direction |
degrees |
Yes |
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WINDSPEEDGRID: |
Wind Speed |
mph |
Yes |
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*Crown Fire Activity classes are ‘No Fire’ (0), ‘Surface Fire’ (1), ‘Passive Crown Fire’ (2), and ‘Active Crown Fire’ (3)
Non-grid outputs
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Switch |
Description |
|---|---|
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WINDVECTOR: |
KMZ of wind vectors. Requires GRIDDED_WINDS_GENERATE: to be ‘yes’ |
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EMBEROUTPUTS: |
Shapefile of the ember locations associated with spotting. Requires SPOTPROBABILITY: to be >0 |
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RANDIGFIRESIZELIST: |
Fire Size List text file that contains the fire number (FireNum), the horizontal coordinate in meters (XStart), the vertical coordinate in meters (Ystart), and the fire size (acres) for each fire simulated |
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OUTPUTFIREPERIMS: |
Shapefile which contains the final fire perimeter for each simulation that successfully completed |
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RANDIGTIMINGS: |
Text file that simulation information related to the RANDIG run |
Switches Not Currently Supported by the FMSF
The FMSF does not currently support all switches available within the RANDIG model. Those not supported are listed below.
CUSTOM_FUELS_FILE: Filename where filename is the name of the desired custom fuels file to use.
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The FMSF does not support custom fuel models currently.
WIND_SPEED_UNITS: X where X is the units of the WIND_SPEED: input (0 – MPH @ 20’, 1 - km/h @ 10m).
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The FMSF only accepts MPH
SPREAD_DIRECTION_FROM_NORTH: X where X is the azimuth to offset spread directions.
GRIDDED_WINDS_DIURNAL: val where val is either ‘Yes’ or ‘No.’
GRIDDED_WINDS_DIURNAL_AIRTEMP: X where X is the air temperature in degrees Fahrenheit.
GRIDDED_WINDS_DIURNAL_CLOUDCOVER: X where X is the percent cloud cover.
GRIDDED_WINDS_DIURNAL_LONGITUDE: X where X is the longitude in decimal degrees.
GRIDDED_WINDS_DIURNAL_DATE: mm dd yyyy where mm is the month, dd is the day of the month, and yyyy is the calendar year.
GRIDDED_WINDS_DIURNAL_TIME: ss mm hh tz where ss is seconds, mm is minutes, hh is hours, tz is time zone, indicates time zone offset from GMT.
GRIDDED_WINDS_DIRECTION_FILE: filename where filename is the path to an ASCII grid of wind azimuths.
GRIDDED_WIND_SPEED_FILE: filename where filename is the path to an ASCII grid of wind velocities in MPH.
RAWS_UNITS: X where X is either the string English or Metric indicating the units for the weather data in the RAWS section as well as the RAWS_ELEVATION.
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The FMSF only accepts English
NodeSpreadNumLat: X where X is the number of columns MTT searches spread times.
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The FMSF set this to 6
NodeSpreadNumVert: X where X is the number of rows MTT searches spread times.
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The FMSF set this to 4