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Added vegtype dependent FRP to FlameH calculations.
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@drnimbusrain
drnimbusrain committed Aug 30, 2023
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2 changes: 1 addition & 1 deletion README.md
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Expand Up @@ -203,7 +203,7 @@ You can also [generate global inputs using Python (see python/global_data_proces
| `lambdars` | Value representing influence of RSL effects (with `rsl_opt=0`) (Massman et al., 2017) |
| `dx_opt` | `0`: Calculation of dx resolution/distance from lon; `1`: user-set dx grid resolution |
| `dx_set` | user-set real value of grid resolution (m) only if `dx_opt=1` |
| `flameh_opt` | `0`: Calculation of flame height from FRP (Byram, 1959); `1`: user-set flameh; `2`: FRP calculation where available (active fires), elsewhere user-set `flameh`; `3`: FlameH override, i.e., only uses fraction of canopy height (`flameh_set` must be <=1.0) as a surrogate for `flameh`; `4`: FRP calculation where available (active fires) and FlameH override elsewhere (same as option 3); `5`: FRP/intensity dependent (i.e., sub-canopy vs. crown fires) calculation where available (active fires) and FlameH override elsewhere (same as option 3). If option 5 is used and crowning is calculated, then the total flame height (i.e., top of canopy=FCH) is used instead of 1/2 flame height. |
| `flameh_opt` | `0`: Calculation of vegtype dependent flame height from FRP (Alexander and Cruz, 2012); `1`: user-set flameh; `2`: FRP calculation where available (active fires), elsewhere user-set `flameh`; `3`: FlameH override, i.e., only uses fraction of canopy height (`flameh_set` must be <=1.0) as a surrogate for `flameh`; `4`: FRP calculation where available (active fires) and FlameH override elsewhere (same as option 3); `5`: FRP/intensity dependent (i.e., sub-canopy vs. crown fires) calculation where available (active fires) and FlameH override elsewhere (same as option 3). If option 5 is used and crowning is calculated, then the total flame height (i.e., top of canopy=FCH) is used instead of 1/2 flame height. |
| `flameh_set` | user-set real value of flame height (m) if `flameh_opt=1` or `2`, or `flameh` = fraction of canopy height (<=1.0), i.e., `flameh` override, if `flameh_opt=3`, `4`, or `5` |
| `frp_fac` | user-set real value of tuning factor applied to FRP in calculation of flame height (default: 1.0). Used only if `flameh_opt=0`, `2`, `4`, or `5`. |
| `pai_opt` | integer (`0`: PAI fixed from Katul et al. 2004 veg types-->default; `1`: PAI Massman et al. 2017 Eq. 19 calc; `2`: PAI from model LAI+WAI; `3`: user-set PAI value) |
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4 changes: 2 additions & 2 deletions src/canopy_calcs.F90
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Expand Up @@ -170,7 +170,7 @@ SUBROUTINE canopy_calcs

! ... determine midflamepoint and flame height from user or FRP calculation
call canopy_flameh(flameh_opt, flameh_set, dx_2d(i,j), modres, &
frpref, frp_fac, hcmref, midflamepoint, flameh_2d(i,j))
frpref, frp_fac, hcmref, lu_opt, vtyperef, midflamepoint, flameh_2d(i,j))
if (firetype .eq. 0) then !forest/sub-canopy firetype
if (flameh_2d(i,j) .gt. 0.0) then !flameh must be > 0
if (flameh_2d(i,j) .le. hcmref) then !only calculate when flameh <= FCH
Expand Down Expand Up @@ -482,7 +482,7 @@ SUBROUTINE canopy_calcs

! ... determine midflamepoint and flame height from user or FRP calculation
call canopy_flameh(flameh_opt, flameh_set, dx(loc), modres, &
frpref, frp_fac, hcmref, midflamepoint, flameh(loc))
frpref, frp_fac, hcmref, lu_opt, vtyperef, midflamepoint, flameh(loc))
if (firetype .eq. 0) then !forest/sub-canopy firetype
if (flameh(loc) .gt. 0.0) then !flameh must be > 0
if (flameh(loc) .le. hcmref) then !only calculate when flameh <= FCH
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181 changes: 170 additions & 11 deletions src/canopy_utils_mod.F90
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Expand Up @@ -108,21 +108,180 @@ real(rk) function CalcDX(lat, dlon) result(dx)
! end function
! !--------------------------------------------------------------------------------------

function CalcFlameH(frp, dx)
!! Approximates the Flame Height as a function of FRP intensity and grid cell distance (dx)
!! forest fraction (Based on Byram 1959).
real(rk) function CalcFlameH(frp, dx, lu_opt, vtype) result( CalcFlameH_set )
!! Approximates the Flame Height as a function of FRP intensity, grid cell distance (dx),
!! and vegetation type (Based on Alexander and Cruz 2012).

!! Byram, GM (1959). Combustion of Forest Fuels. In Forest Fire: Control and Use.
!! (Ed. KP David) pp. 61-89. McGraw Hill, New York, NY
!! Alexander, Martin E.; Cruz, Miguel G. 2012. Interdependencies between flame length and
!! fireline intensity in predicting crown fire initiation and crown scorch height.
!! International Journal of Wildland Fire 21(2):95-113.

!! Assume Flame Length = Flame Height under calm winds

real(rk), intent(in) :: frp !! Input Grid cell Fire Radiative Power (MW/cell)
real(rk), intent(in) :: dx !! Input Grid cell length (m)
real(rk) :: CalcFlameH !! Calculated Plant area index (PAI)

CalcFlameH=0.0775_rk*((frp*1000.0_rk)/dx)**0.46_rk !Byram flameh calculation as function of FRP

real(rk), intent(in) :: frp !! Input Grid cell Fire Radiative Power (MW/cell)
real(rk), intent(in) :: dx !! Input Grid cell length (m)
integer, intent(in) :: lu_opt !! Supported land use classifications
integer, intent(in) :: vtype !! Grid cell dominant vegetation type
real(rk) :: CalcFlameH_B59 !! Fireline intensity flame length (height) relationship (m): Byram (1959)
real(rk) :: CalcFlameH_A66_L !! Fireline intensity to flame height (m): Anderson et al. (1966)
real(rk) :: CalcFlameH_A66_D !! Fireline intensity to flame height (m): Anderson et al. (1966)
real(rk) :: CalcFlameH_N80 !! Fireline intensity to flame height (m): Nelson (1980)
real(rk) :: CalcFlameH_C83_H !! Fireline intensity to flame height (m): Clark (1983)
real(rk) :: CalcFlameH_C83_B !! Fireline intensity to flame height (m): Clark (1983)
real(rk) :: CalcFlameH_N86 !! Fireline intensity to flame height (m): Nelson and Adkins (1986)
real(rk) :: CalcFlameH_V86 !! Fireline intensity to flame height (m): van Wilgen (1986)
real(rk) :: CalcFlameH_B94 !! Fireline intensity to flame height (m): Burrows (1994)
real(rk) :: CalcFlameH_W96 !! Fireline intensity to flame height (m): Weise and Biging (1996)
real(rk) :: CalcFlameH_V98 !! Fireline intensity to flame height (m): Vega et al. (1998)
real(rk) :: CalcFlameH_C98 !! Fireline intensity to flame height (m): Catchpole et al. (1998)
real(rk) :: CalcFlameH_F00 !! Fireline intensity to flame height (m): Fernandes et al. (2000)
real(rk) :: CalcFlameH_B04 !! Fireline intensity to flame height (m): Butler et al. (2004)
real(rk) :: CalcFlameH_F09_H !! Fireline intensity to flame height (m): Fernandes et al. (2009)
real(rk) :: CalcFlameH_F09_B !! Fireline intensity to flame height (m): Fernandes et al. (2009)

!! -------------------------------------------------------------------------------------
!! Byram, GM (1959). Combustion of Forest Fuels. In Forest Fire: Control and Use.
!! (Ed. KP David) pp. 61-89. McGraw Hill, New York, NY
!Pine litter with grass understorey (Evergreen and Grasses)
CalcFlameH_B59=0.0775_rk*((frp*1000.0_rk)/dx)**0.46_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Anderson HE, Brackebusch AP, Mutch RW, Rothermel RC (1966) Mechanisms of fire spread
!! research progress report 2. USDA Forest Service,
!! Intermountain Forest and Range Experiment Station, Research Paper
!! INT-28. (Ogden, UT)
!Lodgepole pine slash (Evergreen)
CalcFlameH_A66_L=0.074_rk*((frp*1000.0_rk)/dx)**0.651_rk
!Douglas-fir slash (Evergreen)
CalcFlameH_A66_D=0.0447_rk*((frp*1000.0_rk)/dx)**0.67_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Nelson RM Jr (1980) Flame characteristics for fires in southern fuels. USDA
!! Forest Service, Southeastern Forest Experiment Station, Research Paper
!! SE-205. (Asheville, NC)
!Southern USA Fuels (Mixed Forest)
CalcFlameH_N80=0.0377_rk*((frp*1000.0_rk)/dx)**0.50_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Clark RG (1983) Threshold requirements for fire spread in grassland fuels.
!! PhD dissertation, Texas Tech University, Lubbock.
!Grasslands (head fire) (Grasslands)
CalcFlameH_C83_H=0.00015_rk*((frp*1000.0_rk)/dx)**1.75_rk
!Grasslands (backfire) (Grasslands)
CalcFlameH_C83_B=0.000722_rk*((frp*1000.0_rk)/dx)**0.99_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Nelson RM Jr, Adkins CW (1986) Flame characteristics of wind-driven
!! surface fires. Canadian Journal of Forest Research 16, 1293–1300.
!! doi:10.1139/X86-229
!Litter and shrubs (Shrublands)
CalcFlameH_N86=0.0475_rk*((frp*1000.0_rk)/dx)**0.493_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! van Wilgen BW (1986) A simple relationship for estimating the intensity of
!! fires in natural vegetation. South African Journal of Botany 52, 384–385
!Fynbos shrublands (Shrublands)
CalcFlameH_V86=0.0075_rk*((frp*1000.0_rk)/dx)**0.46_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Burrows ND (1994) Experimental development of a fire management model
!! for jarrah (Eucalyptus marginata Donn ex Sm.) forest. PhD thesis,
!! Australian National University, Canberra.
!Eucalypt Forest (Evergreens)
CalcFlameH_B94=0.0147_rk*((frp*1000.0_rk)/dx)**0.767_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Weise DR, Biging GS (1996) Effects of wind velocity and slope on flame
!! properties. Canadian Journal of Forest Research 26, 1849–1858.
!! doi:10.1139/X26-210
!Excelsior (Deciduous)
CalcFlameH_W96=0.016_rk*((frp*1000.0_rk)/dx)**0.7_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Vega JA, Cuinas P, Fonturbel T, Perez-Gorostiaga P, Fernandez C (1998)
!! Predicting fire behaviour in Galician (NW Spain) shrubland fuel
!! complexes. In ‘Proceedings of 3rd International Conference on Forest
!! Flame length and fireline intensity interdependences.
!Shrublands
CalcFlameH_V98=0.087_rk*((frp*1000.0_rk)/dx)**0.493_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! CatchpoleWR, Bradstock RA, Choate J, Fogarty LG, Gellie N, McCarthy G,
!! McCaw WL, Marsden-Smedley JB, Pearce G (1998) Cooperative
!! development of equations for heathland fire behaviour. In ‘Proceedings
!! of 3rd International Conference on Forest Fire Research and 14th
!! Conference on Fire and Forest Meteorology, Volume II’, 16–20
!! November 1998, Luso–Coimbra, Portugal. (Ed. DX Viegas)
!! pp. 631–645. (University of Coimbra: Coimbra, Portugal)
!Shrublands
CalcFlameH_C98=0.0325_rk*((frp*1000.0_rk)/dx)**0.56_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Fernandes PM, Catchpole WR, Rego FC (2000) Shrubland fire behaviour
!! modelling with microplot data.Canadian Journal of Forest Research 30,
!! 889–899. doi:10.1139/X00-012
!Shrublands
CalcFlameH_F00=0.0516_rk*((frp*1000.0_rk)/dx)**0.453_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Butler BW, Finney MA, Andrews PL, Albini FA (2004) A radiation-driven
!! model of crown fire spread. Canadian Journal of Forest Research 34,
!! 1588–1599. doi:10.1139/X04-074
!Jack Pine Forest - Crown Fire (Evergreen)
CalcFlameH_B04=0.0175_rk*((frp*1000.0_rk)/dx)**0.667_rk
!! -------------------------------------------------------------------------------------

!! -------------------------------------------------------------------------------------
!! Fernandes PM, Botelho HS, Rego FC, Loureiro C (2009) Empirical
!! modelling of surface fire behaviour in maritime pine stands.
!! International Journal of Wildland Fire 18, 698–710. doi:10.1071/
!! WF08023
!Maritime Pine (head fire) (Evergreen)
CalcFlameH_F09_H=0.045_rk*((frp*1000.0_rk)/dx)**0.543_rk
!Maritime Pine (backfire) (Evergreen)
CalcFlameH_F09_B=0.029_rk*((frp*1000.0_rk)/dx)**0.724_rk
!! -------------------------------------------------------------------------------------

if (lu_opt .eq. 0 .or. lu_opt .eq. 1) then !VIIRS or MODIS LU types
if (vtype .ge. 1 .and. vtype .le. 2) then !VIIRS/MODIS Cat 1-2/Evergreen Needleleaf & Broadleaf
CalcFlameH_set=(CalcFlameH_B59+CalcFlameH_A66_L+CalcFlameH_A66_D+CalcFlameH_B94+ &
CalcFlameH_F09_H+CalcFlameH_F09_B) / 6.0_rk
if (((frp*1000.0_rk)/dx) .ge. 1700.0_rk ) then !Evergreen forest crowning likely
CalcFlameH_set=CalcFlameH_B04
end if
else if (vtype .ge. 3 .and. vtype .le. 4) then !VIIRS/MODIS Cat 3-4 Deciduous Needleleaf and Broadleaf
CalcFlameH_set=(CalcFlameH_N80+CalcFlameH_W96) / 2.0_rk
else if (vtype .eq. 5) then !VIIRS/MODIS Cat 5 Mixed Forests
CalcFlameH_set=CalcFlameH_N80
else if (vtype .ge. 6 .and. vtype .le. 7) then !VIIRS/MODIS Cat 6-7 Shrublands
CalcFlameH_set=(CalcFlameH_N86+CalcFlameH_V86+CalcFlameH_V98+CalcFlameH_C98+ &
CalcFlameH_F00) / 5.0_rk
else if (vtype .ge. 8 .and. vtype .le. 10) then !VIIRS/MODIS Cat 8-10 Savannas and Grasslands
CalcFlameH_set=(CalcFlameH_B59+CalcFlameH_C83_H+CalcFlameH_C83_B) / 3.0_rk
else if (vtype .ge. 12) then !VIIRS/MODIS Cat 12 Croplands
CalcFlameH_set=(CalcFlameH_B59+CalcFlameH_C83_H+CalcFlameH_C83_B) / 3.0_rk
else
CalcFlameH_set=(CalcFlameH_B59+CalcFlameH_A66_L+CalcFlameH_A66_D+CalcFlameH_N80+ &
CalcFlameH_C83_H+CalcFlameH_C83_B+CalcFlameH_N86+CalcFlameH_V86+ &
CalcFlameH_B94+CalcFlameH_W96+CalcFlameH_V98+CalcFlameH_C98+ &
CalcFlameH_F00+CalcFlameH_B04+CalcFlameH_F09_H+ &
CalcFlameH_F09_B) / 16.0_rk
end if
else
write(*,*) 'Wrong LU_OPT choice of ', LU_OPT, 'in namelist, only VIIRS/MODIS available right now...exiting'
call exit(2)
end if
end function

real(rk) function GET_GAMMA_CO2(co2_opt, co2_set) result( GAMMA_CO2 )
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12 changes: 7 additions & 5 deletions src/canopy_waf_mod.F90
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Expand Up @@ -6,7 +6,7 @@ module canopy_waf_mod

!:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
SUBROUTINE CANOPY_FLAMEH( FLAMEH_OPT, FLAMEH_SET, DX, MODRES, &
FRP_IN, FRP_FAC, FCH, MIDFLAMEPOINT, FLAMEH )
FRP_IN, FRP_FAC, FCH, LU_OPT, VTYPE, MIDFLAMEPOINT, FLAMEH )

!-----------------------------------------------------------------------

Expand Down Expand Up @@ -34,6 +34,8 @@ SUBROUTINE CANOPY_FLAMEH( FLAMEH_OPT, FLAMEH_SET, DX, MODRES, &
REAL(RK), INTENT( IN ) :: FRP_IN ! Model input FRP (MW/grid cell area)
REAL(RK), INTENT( IN ) :: FRP_FAC ! FRP tuning factor for flame height calculation
REAL(RK), INTENT( IN ) :: FCH ! Grid cell canopy height (m)
INTEGER, INTENT( IN ) :: LU_OPT ! Supported land use classifications
INTEGER, INTENT( IN ) :: VTYPE ! Dominant vegetation type
INTEGER, INTENT( OUT ) :: MIDFLAMEPOINT ! Indice of the mid-flame point
REAL(RK), INTENT( OUT ) :: FLAMEH ! Flame Height (m)

Expand All @@ -50,13 +52,13 @@ SUBROUTINE CANOPY_FLAMEH( FLAMEH_OPT, FLAMEH_SET, DX, MODRES, &
FLAMEH_SET, ' from namelist'
FLAMEH = FLAMEH_SET
else !calculate flameh
FLAMEH = CalcFlameH(frp,DX)
FLAMEH = CalcFlameH(frp,DX,LU_OPT,VTYPE)
end if
else if (FLAMEH_OPT .eq. 1) then !user set value
FLAMEH = FLAMEH_SET
else if (FLAMEH_OPT .eq. 2) then !both FRP calc and user set
if (frp .gt. 0.0) then
FLAMEH = CalcFlameH(frp,DX)
FLAMEH = CalcFlameH(frp,DX,LU_OPT,VTYPE)
else
FLAMEH = FLAMEH_SET
end if
Expand All @@ -69,7 +71,7 @@ SUBROUTINE CANOPY_FLAMEH( FLAMEH_OPT, FLAMEH_SET, DX, MODRES, &
end if
else if (FLAMEH_OPT .eq. 4) then !uses FRP and overide elsewhere
if (frp .gt. 0.0) then
FLAMEH = CalcFlameH(frp,DX)
FLAMEH = CalcFlameH(frp,DX,LU_OPT,VTYPE)
else
if (FLAMEH_SET .le. 1.0) then
FLAMEH = FCH * FLAMEH_SET !not real flame height but uses WAF at this fractional FCH
Expand All @@ -83,7 +85,7 @@ SUBROUTINE CANOPY_FLAMEH( FLAMEH_OPT, FLAMEH_SET, DX, MODRES, &
if ( ((frp*1000.0_rk)/DX) .ge. 1700.0_rk ) then !Crown fire likely (Andrews et al., 2011).
FLAMEH = FCH !https://doi.org/10.2737/RMRS-GTR-253
else
FLAMEH = CalcFlameH(frp,DX)
FLAMEH = CalcFlameH(frp,DX,LU_OPT,VTYPE)
end if
else
if (FLAMEH_SET .le. 1.0) then
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