Add snow Age parameter for tuning

CMCC-Foundation · Oct 6, 2023 · 9bf40a4 · 9bf40a4
1 parent 5249cc9
commit 9bf40a4
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Showing 4 changed files with 18 additions and 6 deletions.
diff --git a/bld/namelist_files/namelist_definition_ctsm.xml b/bld/namelist_files/namelist_definition_ctsm.xml
@@ -939,6 +939,11 @@ Perturbation limit when doing error growth test
 If FALSE, don't write any restart files.
 </entry>
 
+<entry id="snoage_scl" type="real" category="clm_physics"
+       group="clm_inparm" valid_values="" >
+If greater than zero it activates the snow aging scaling factor using the provided value.
+</entry>
+
 <entry id="urban_hac" type="char*16" category="clm_physics"
        group="clmu_inparm" valid_values="OFF,ON,ON_WASTEHEAT" >
 Turn urban air conditioning/heating ON or OFF and add wasteheat:

diff --git a/src/biogeophys/SnowSnicarMod.F90 b/src/biogeophys/SnowSnicarMod.F90
@@ -1058,6 +1058,7 @@ subroutine SnowAge_grain(bounds, &
     use clm_varpar       , only : nlevsno
     use clm_varcon       , only : spval
     use shr_const_mod    , only : SHR_CONST_RHOICE, SHR_CONST_PI
+    use clm_varctl       , only : snoage_scl
     !
     ! !ARGUMENTS:
     type(bounds_type)      , intent(in)    :: bounds  
@@ -1228,11 +1229,10 @@ subroutine SnowAge_grain(bounds, &
             !**********  3. SNOWAGE SCALING (TURNED OFF BY DEFAULT)  *************
             !
             ! Multiply rate of change of effective radius by some constant, xdrdt
-            if (flg_snoage_scl) then
-               dr = dr*params_inst%xdrdt
+            if (snoage_scl .gt. 0._r8) then
+               dr = dr*snoage_scl
             endif
 
-
             !
             !**********  4. INCREMENT EFFECTIVE RADIUS, ACCOUNTING FOR:  ***********
             !               DRY AGING

diff --git a/src/main/clm_varctl.F90 b/src/main/clm_varctl.F90
@@ -407,7 +407,10 @@ module clm_varctl
   logical, public :: use_noio            = .false.
 
   logical, public :: use_nguardrail      = .false.
-
+  !----------------------------------------------------------
+  ! scaling of the snow aging rate (tuning option)
+  !----------------------------------------------------------
+  real(r8), public :: snoage_scl = 0.0_r8    ! arbitrary factor applied to snow aging rate if greater than 0
   !----------------------------------------------------------
   ! To retrieve namelist
   !----------------------------------------------------------

diff --git a/src/main/controlMod.F90 b/src/main/controlMod.F90
@@ -282,6 +282,8 @@ subroutine control_init(dtime)
          use_grainproduct, use_snicar_frc, use_vancouver, use_mexicocity, use_noio, &
          use_nguardrail
 
+    ! Scaling of snow aging rate
+    namelist /clm_inparm/ snoage_scl
 
     ! ----------------------------------------------------------------------
     ! Default values
@@ -336,7 +338,8 @@ subroutine control_init(dtime)
        else
           call endrun(msg='ERROR finding clm_nitrogen namelist'//errMsg(sourcefile, __LINE__))
        end if
-
+       write(iulog,*) "#  CLM clm_inparm :"
+       write(iulog,*) 'SNOAGE_SCL is set to: ', snoage_scl
        call relavu( unitn )
 
        ! ----------------------------------------------------------------------
@@ -838,7 +841,8 @@ subroutine control_spmd()
 
     call mpi_bcast (clump_pproc, 1, MPI_INTEGER, 0, mpicom, ier)
 
-
+    ! scaling of the snow aging rate (tuning option)
+    call mpi_bcast (snoage_scl, 1, MPI_REAL8, 0, mpicom, ier)
   end subroutine control_spmd
 
   !------------------------------------------------------------------------