Call routine to calc fire's btran2 from CNFireArea

This has a few advantages:
- It makes the logic of CNFireArea more clear (rather than depending on
  a btran2 variable that is calculated from some other part of the code)

- This avoids having the biogeophysics depend on the biogeochemistry

- This lets us avoid doing this btran calc if using no-fire – or other,
  future, fire methods that don't need it

The placement in the driver loop differs from before; in order to get
bit-for-bit results, we need to save h2osoi_vol and used that saved
version from earlier in the driver loop; in a follow-up, answer-changing
step, I plan to change this.

src/biogeochem/CNDriverMod.F90

@@ -40,6 +40,7 @@ module CNDriverMod
   use EnergyFluxType                  , only : energyflux_type
   use SaturatedExcessRunoffMod        , only : saturated_excess_runoff_type
   use ActiveLayerMod                  , only : active_layer_type
+  use SoilWaterRetentionCurveMod      , only : soil_water_retention_curve_type
   !
   ! !PUBLIC TYPES:
   implicit none
@@ -80,7 +81,8 @@ end subroutine CNDriverInit
 
   !-----------------------------------------------------------------------
   subroutine CNDriverNoLeaching(bounds,                                                    &
-       num_soilc, filter_soilc, num_soilp, filter_soilp, num_pcropp, filter_pcropp, doalb, &
+       num_soilc, filter_soilc, num_soilp, filter_soilp, num_pcropp, filter_pcropp,        &
+       num_exposedvegp, filter_exposedvegp, doalb,                                         &
        cnveg_state_inst,                                                                   &
        cnveg_carbonflux_inst, cnveg_carbonstate_inst,                                      &
        c13_cnveg_carbonflux_inst, c13_cnveg_carbonstate_inst,                              &
@@ -94,7 +96,8 @@ subroutine CNDriverNoLeaching(bounds,
        soilbiogeochem_nitrogenflux_inst, soilbiogeochem_nitrogenstate_inst,                &
        active_layer_inst,                                                                  &
        atm2lnd_inst, waterstatebulk_inst, waterdiagnosticbulk_inst, waterfluxbulk_inst,    &
-       wateratm2lndbulk_inst, canopystate_inst, soilstate_inst, temperature_inst, crop_inst, ch4_inst,            &
+       wateratm2lndbulk_inst, canopystate_inst, soilstate_inst, temperature_inst,          &
+       soil_water_retention_curve, crop_inst, ch4_inst,            &
        dgvs_inst, photosyns_inst, saturated_excess_runoff_inst, energyflux_inst,                   &
        nutrient_competition_method, cnfire_method, dribble_crophrv_xsmrpool_2atm)
     !
@@ -146,6 +149,8 @@ subroutine CNDriverNoLeaching(bounds,
     integer                                 , intent(in)    :: filter_soilp(:)   ! filter for soil patches
     integer                                 , intent(in)    :: num_pcropp        ! number of prog. crop patches in filter
     integer                                 , intent(in)    :: filter_pcropp(:)  ! filter for prognostic crop patches
+    integer                                 , intent(in)    :: num_exposedvegp        ! number of points in filter_exposedvegp
+    integer                                 , intent(in)    :: filter_exposedvegp(:)  ! patch filter for non-snow-covered veg
     logical                                 , intent(in)    :: doalb             ! true = surface albedo calculation time step
     type(cnveg_state_type)                  , intent(inout) :: cnveg_state_inst
     type(cnveg_carbonflux_type)             , intent(inout) :: cnveg_carbonflux_inst
@@ -178,6 +183,7 @@ subroutine CNDriverNoLeaching(bounds,
     type(canopystate_type)                  , intent(inout)    :: canopystate_inst
     type(soilstate_type)                    , intent(inout) :: soilstate_inst
     type(temperature_type)                  , intent(inout) :: temperature_inst
+    class(soil_water_retention_curve_type)  , intent(in)    :: soil_water_retention_curve
     type(crop_type)                         , intent(inout) :: crop_inst
     type(ch4_type)                          , intent(in)    :: ch4_inst
     type(dgvs_type)                         , intent(inout) :: dgvs_inst
@@ -747,7 +753,9 @@ subroutine CNDriverNoLeaching(bounds,
 
     call t_startf('CNFire')
     call cnfire_method%CNFireArea(bounds, num_soilc, filter_soilc, num_soilp, filter_soilp, &
+         num_exposedvegp, filter_exposedvegp, &
          atm2lnd_inst, energyflux_inst, saturated_excess_runoff_inst, waterdiagnosticbulk_inst, wateratm2lndbulk_inst, &
+         waterstatebulk_inst, soilstate_inst, soil_water_retention_curve, &
          cnveg_state_inst, cnveg_carbonstate_inst, &
          totlitc_col=soilbiogeochem_carbonstate_inst%totlitc_col(begc:endc), &
          decomp_cpools_vr_col=soilbiogeochem_carbonstate_inst%decomp_cpools_vr_col(begc:endc,1:nlevdecomp_full,1:ndecomp_pools), &

src/biogeochem/CNFireBaseMod.F90

@@ -84,7 +84,6 @@ module CNFireBaseMod
       procedure, public :: FireReadNML                   ! Read in namelist for CNFire
       procedure, public :: CNFireRestart                 ! Restart for CNFire
       procedure, public :: CNFireReadParams              ! Read in constant parameters from the paramsfile
-      procedure, public :: CNFireArea                    ! Calculate fire area
       procedure, public :: CNFireFluxes                  ! Calculate fire fluxes
       procedure, public :: CNFire_calc_fire_root_wetness ! Calcualte CN-fire specific root wetness
       !
@@ -168,19 +167,19 @@ subroutine CNFireRestart( this, bounds, ncid, flag )
   end subroutine CNFireRestart
 
   !----------------------------------------------------------------------
-  subroutine CNFire_calc_fire_root_wetness( this, bounds, nlevgrnd, num_exposedvegp, filter_exposedvegp, &
+  subroutine CNFire_calc_fire_root_wetness( this, bounds, num_exposedvegp, filter_exposedvegp, &
                                      waterstatebulk_inst, soilstate_inst, soil_water_retention_curve )
     !
     ! Calculate the root wetness term that will be used by the fire model
     !
     use pftconMod                 , only : pftcon
+    use clm_varpar                , only : nlevgrnd
     use PatchType                 , only : patch
     use WaterStateBulkType        , only : waterstatebulk_type
     use SoilStateType             , only : soilstate_type
     use SoilWaterRetentionCurveMod, only : soil_water_retention_curve_type
     class(cnfire_base_type) :: this
     type(bounds_type)      , intent(in)   :: bounds                         !bounds
-    integer                , intent(in)   :: nlevgrnd                       !number of vertical layers
     integer                , intent(in)   :: num_exposedvegp                !number of filters
     integer                , intent(in)   :: filter_exposedvegp(:)          !filter array
     type(waterstatebulk_type), intent(in) :: waterstatebulk_inst
@@ -201,13 +200,10 @@ subroutine CNFire_calc_fire_root_wetness( this, bounds, nlevgrnd, num_exposedveg
          watsat        => soilstate_inst%watsat_col         , & ! Input:  [real(r8) (:,:) ]  volumetric soil water at saturation
          btran2        => this%btran2_patch                 , & ! Output: [real(r8) (:)   ]  integrated soil water stress square
          rootfr        => soilstate_inst%rootfr_patch       , & ! Input:  [real(r8) (:,:) ]  fraction of roots in each soil layer
-         h2osoi_vol    => waterstatebulk_inst%h2osoi_vol_col  & ! Input:  [real(r8) (:,:) ]  volumetric soil water (0<=h2osoi_vol<=watsat) [m3/m3] (porosity)   (constant)
+         ! FIXME(wjs, 2020-09-18) change this to use h2osoi_vol_col instead of the prehydrology version
+         h2osoi_vol    => waterstatebulk_inst%h2osoi_vol_prehydrology_col  & ! Input:  [real(r8) (:,:) ]  volumetric soil water (0<=h2osoi_vol<=watsat) [m3/m3] (porosity)   (constant)
          )
 
-      SHR_ASSERT_ALL_FL((ubound(watsat)     == (/bounds%endc,nlevgrnd/)), sourcefile, __LINE__)
-      SHR_ASSERT_ALL_FL((ubound(h2osoi_vol) == (/bounds%endc,nlevgrnd/)), sourcefile, __LINE__)
-      SHR_ASSERT_ALL_FL((ubound(rootfr)     == (/bounds%endp,nlevgrnd/)), sourcefile, __LINE__)
-      SHR_ASSERT_ALL_FL((ubound(btran2)     == (/bounds%endp/)),          sourcefile, __LINE__)
       do f = 1, num_exposedvegp
          p = filter_exposedvegp(f)
          btran2(p)   = btran0
@@ -338,40 +334,6 @@ subroutine FireReadNML( this, NLFilename )
 
   end subroutine FireReadNML
 
-  !-----------------------------------------------------------------------
-  subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_soilp, &
-       atm2lnd_inst, energyflux_inst, saturated_excess_runoff_inst, &
-       waterdiagnosticbulk_inst, wateratm2lndbulk_inst, &
-       cnveg_state_inst, cnveg_carbonstate_inst, totlitc_col, decomp_cpools_vr_col, t_soi17cm_col)
-    !
-    ! !DESCRIPTION:
-    ! Computes column-level burned area 
-    !
-    ! !USES:
-    !
-    ! !ARGUMENTS:
-    class(cnfire_base_type)                               :: this
-    type(bounds_type)                     , intent(in)    :: bounds 
-    integer                               , intent(in)    :: num_soilc       ! number of soil columns in filter
-    integer                               , intent(in)    :: filter_soilc(:) ! filter for soil columns
-    integer                               , intent(in)    :: num_soilp       ! number of soil patches in filter
-    integer                               , intent(in)    :: filter_soilp(:) ! filter for soil patches
-    type(atm2lnd_type)                    , intent(in)    :: atm2lnd_inst
-    type(energyflux_type)                 , intent(in)    :: energyflux_inst
-    type(saturated_excess_runoff_type)    , intent(in)    :: saturated_excess_runoff_inst
-    type(waterdiagnosticbulk_type)                 , intent(in)    :: waterdiagnosticbulk_inst
-    type(wateratm2lndbulk_type)                 , intent(in)    :: wateratm2lndbulk_inst
-    type(cnveg_state_type)                , intent(inout) :: cnveg_state_inst
-    type(cnveg_carbonstate_type)          , intent(inout) :: cnveg_carbonstate_inst
-    real(r8)                              , intent(in)    :: totlitc_col(bounds%begc:)
-    real(r8)                              , intent(in)    :: decomp_cpools_vr_col(bounds%begc:,1:,1:)
-    real(r8)                              , intent(in)    :: t_soi17cm_col(bounds%begc:)
-    !
-
-    call endrun( 'cnfire_base::CNFireArea: this method MUST be implemented!' )
-
-  end subroutine CNFireArea
-
   !-----------------------------------------------------------------------
   subroutine CNFireFluxes (this, bounds, num_soilc, filter_soilc, num_soilp, filter_soilp, &
       dgvs_inst, cnveg_state_inst,                                                                      &

src/biogeochem/CNFireLi2014Mod.F90

@@ -34,8 +34,11 @@ module CNFireLi2014Mod
   use SoilBiogeochemDecompCascadeConType , only : decomp_cascade_con
   use EnergyFluxType                     , only : energyflux_type
   use SaturatedExcessRunoffMod           , only : saturated_excess_runoff_type
-  use WaterDiagnosticBulkType                     , only : waterdiagnosticbulk_type
-  use Wateratm2lndBulkType                     , only : wateratm2lndbulk_type
+  use WaterDiagnosticBulkType            , only : waterdiagnosticbulk_type
+  use Wateratm2lndBulkType               , only : wateratm2lndbulk_type
+  use WaterStateBulkType                 , only : waterstatebulk_type
+  use SoilStateType                      , only : soilstate_type
+  use SoilWaterRetentionCurveMod         , only : soil_water_retention_curve_type
   use GridcellType                       , only : grc                
   use ColumnType                         , only : col                
   use PatchType                          , only : patch                
@@ -79,8 +82,10 @@ end function need_lightning_and_popdens
 
   !-----------------------------------------------------------------------
   subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_soilp, &
+       num_exposedvegp, filter_exposedvegp, &
        atm2lnd_inst, energyflux_inst, saturated_excess_runoff_inst, waterdiagnosticbulk_inst, &
-       wateratm2lndbulk_inst, cnveg_state_inst, cnveg_carbonstate_inst, totlitc_col, decomp_cpools_vr_col, t_soi17cm_col)
+       wateratm2lndbulk_inst, waterstatebulk_inst, soilstate_inst, soil_water_retention_curve, &
+       cnveg_state_inst, cnveg_carbonstate_inst, totlitc_col, decomp_cpools_vr_col, t_soi17cm_col)
     !
     ! !DESCRIPTION:
     ! Computes column-level burned area 
@@ -100,11 +105,16 @@ subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_
     integer                               , intent(in)    :: filter_soilc(:) ! filter for soil columns
     integer                               , intent(in)    :: num_soilp       ! number of soil patches in filter
     integer                               , intent(in)    :: filter_soilp(:) ! filter for soil patches
+    integer                               , intent(in)    :: num_exposedvegp        ! number of points in filter_exposedvegp
+    integer                               , intent(in)    :: filter_exposedvegp(:)  ! patch filter for non-snow-covered veg
     type(atm2lnd_type)                    , intent(in)    :: atm2lnd_inst
     type(energyflux_type)                 , intent(in)    :: energyflux_inst
     type(saturated_excess_runoff_type)    , intent(in)    :: saturated_excess_runoff_inst
-    type(waterdiagnosticbulk_type)                 , intent(in)    :: waterdiagnosticbulk_inst
-    type(wateratm2lndbulk_type)                 , intent(in)    :: wateratm2lndbulk_inst
+    type(waterdiagnosticbulk_type)        , intent(in)    :: waterdiagnosticbulk_inst
+    type(wateratm2lndbulk_type)           , intent(in)    :: wateratm2lndbulk_inst
+    type(waterstatebulk_type)             , intent(in)    :: waterstatebulk_inst
+    type(soilstate_type)                  , intent(in)    :: soilstate_inst
+    class(soil_water_retention_curve_type), intent(in)    :: soil_water_retention_curve
     type(cnveg_state_type)                , intent(inout) :: cnveg_state_inst
     type(cnveg_carbonstate_type)          , intent(inout) :: cnveg_carbonstate_inst
     real(r8)                              , intent(in)    :: totlitc_col(bounds%begc:)
@@ -322,6 +332,10 @@ subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_
            dtrotr_col(c)=0._r8
         end if
      end do
+
+     call this%CNFire_calc_fire_root_wetness(bounds, num_exposedvegp, filter_exposedvegp, &
+          waterstatebulk_inst, soilstate_inst, soil_water_retention_curve)
+
      do pi = 1,max_patch_per_col
         do fc = 1,num_soilc
            c = filter_soilc(fc)

src/biogeochem/CNFireLi2016Mod.F90

@@ -34,8 +34,11 @@ module CNFireLi2016Mod
   use SoilBiogeochemDecompCascadeConType , only : decomp_cascade_con
   use EnergyFluxType                     , only : energyflux_type
   use SaturatedExcessRunoffMod           , only : saturated_excess_runoff_type
-  use WaterDiagnosticBulkType                     , only : waterdiagnosticbulk_type
-  use Wateratm2lndBulkType                     , only : wateratm2lndbulk_type
+  use WaterDiagnosticBulkType            , only : waterdiagnosticbulk_type
+  use Wateratm2lndBulkType               , only : wateratm2lndbulk_type
+  use WaterStateBulkType                 , only : waterstatebulk_type
+  use SoilStateType                      , only : soilstate_type
+  use SoilWaterRetentionCurveMod         , only : soil_water_retention_curve_type
   use GridcellType                       , only : grc                
   use ColumnType                         , only : col                
   use PatchType                          , only : patch                
@@ -83,8 +86,10 @@ end function need_lightning_and_popdens
 
   !-----------------------------------------------------------------------
   subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_soilp, &
+       num_exposedvegp, filter_exposedvegp, &
        atm2lnd_inst, energyflux_inst, saturated_excess_runoff_inst, waterdiagnosticbulk_inst, &
-       wateratm2lndbulk_inst, cnveg_state_inst, cnveg_carbonstate_inst, totlitc_col, decomp_cpools_vr_col, t_soi17cm_col)
+       wateratm2lndbulk_inst, waterstatebulk_inst, soilstate_inst, soil_water_retention_curve, &
+       cnveg_state_inst, cnveg_carbonstate_inst, totlitc_col, decomp_cpools_vr_col, t_soi17cm_col)
     !
     ! !DESCRIPTION:
     ! Computes column-level burned area 
@@ -105,11 +110,16 @@ subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_
     integer                               , intent(in)    :: filter_soilc(:) ! filter for soil columns
     integer                               , intent(in)    :: num_soilp       ! number of soil patches in filter
     integer                               , intent(in)    :: filter_soilp(:) ! filter for soil patches
+    integer                               , intent(in)    :: num_exposedvegp        ! number of points in filter_exposedvegp
+    integer                               , intent(in)    :: filter_exposedvegp(:)  ! patch filter for non-snow-covered veg
     type(atm2lnd_type)                    , intent(in)    :: atm2lnd_inst
     type(energyflux_type)                 , intent(in)    :: energyflux_inst
     type(saturated_excess_runoff_type)    , intent(in)    :: saturated_excess_runoff_inst
-    type(waterdiagnosticbulk_type)                 , intent(in)    :: waterdiagnosticbulk_inst
-    type(wateratm2lndbulk_type)                 , intent(in)    :: wateratm2lndbulk_inst
+    type(waterdiagnosticbulk_type)        , intent(in)    :: waterdiagnosticbulk_inst
+    type(wateratm2lndbulk_type)           , intent(in)    :: wateratm2lndbulk_inst
+    type(waterstatebulk_type)             , intent(in)    :: waterstatebulk_inst
+    type(soilstate_type)                  , intent(in)    :: soilstate_inst
+    class(soil_water_retention_curve_type), intent(in)    :: soil_water_retention_curve
     type(cnveg_state_type)                , intent(inout) :: cnveg_state_inst
     type(cnveg_carbonstate_type)          , intent(inout) :: cnveg_carbonstate_inst
     real(r8)                              , intent(in)    :: totlitc_col(bounds%begc:)
@@ -343,6 +353,10 @@ subroutine CNFireArea (this, bounds, num_soilc, filter_soilc, num_soilp, filter_
            dtrotr_col(c)=0._r8
         end if
      end do
+
+     call this%CNFire_calc_fire_root_wetness(bounds, num_exposedvegp, filter_exposedvegp, &
+          waterstatebulk_inst, soilstate_inst, soil_water_retention_curve)
+
      do pi = 1,max_patch_per_col
         do fc = 1,num_soilc
            c = filter_soilc(fc)