+Add density rescaling factors in unit_scale_type

Added factors for power-of-2 rescaling of density to the unit_scale_type, along with the new run-time parameter R_RESCALE_POWER. All answers are bitwise identical, but there is a new runtime parameter, some new elements in a transparent public type, and a new optional variable in the MOM restart files. This adds a new entry to the MOM_parameter_doc.debugging files.
NOAA-GFDL · Sep 11, 2019 · 3704a66 · 3704a66
1 parent 1016be3
commit 3704a66
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Showing 2 changed files with 22 additions and 5 deletions.
diff --git a/src/core/MOM.F90 b/src/core/MOM.F90
@@ -2558,7 +2558,7 @@ subroutine MOM_timing_init(CS)
    id_clock_diabatic = cpu_clock_id('(Ocean diabatic driver)', grain=CLOCK_MODULE_DRIVER)
 
  id_clock_continuity = cpu_clock_id('(Ocean continuity equation *)', grain=CLOCK_MODULE)
- id_clock_BBL_visc = cpu_clock_id('(Ocean set BBL viscosity)', grain=CLOCK_MODULE)
+ id_clock_BBL_visc   = cpu_clock_id('(Ocean set BBL viscosity)', grain=CLOCK_MODULE)
  id_clock_pass       = cpu_clock_id('(Ocean message passing *)', grain=CLOCK_MODULE)
  id_clock_MOM_init   = cpu_clock_id('(Ocean MOM_initialize_state)', grain=CLOCK_MODULE)
  id_clock_pass_init  = cpu_clock_id('(Ocean init message passing *)', grain=CLOCK_ROUTINE)
@@ -2644,6 +2644,8 @@ subroutine set_restart_fields(GV, US, param_file, CS, restart_CSp)
                               "Length unit conversion factor", "L meter-1")
   call register_restart_field(US%s_to_T_restart, "s_to_T", .false., restart_CSp, &
                               "Time unit conversion factor", "T second-1")
+  call register_restart_field(US%kg_m3_to_R_restart, "kg_m3_to_R", .false., restart_CSp, &
+                              "Density unit conversion factor", "R m3 kg-1")
 
 end subroutine set_restart_fields
 

diff --git a/src/framework/MOM_unit_scaling.F90 b/src/framework/MOM_unit_scaling.F90
@@ -16,8 +16,10 @@ module MOM_unit_scaling
   real :: Z_to_m !< A constant that translates distances in the units of depth to meters.
   real :: m_to_L !< A constant that translates lengths in meters to the units of horizontal lengths.
   real :: L_to_m !< A constant that translates lengths in the units of horizontal lengths to meters.
-  real :: s_to_T !< A constant that time intervals in seconds to the units of time.
-  real :: T_to_s !< A constant that the units of time to seconds.
+  real :: s_to_T !< A constant that translates time intervals in seconds to the units of time.
+  real :: T_to_s !< A constant that translates the units of time to seconds.
+  real :: R_to_kg_m3 !< A constant that translates the units of density to kilograms per meter cubed.
+  real :: kg_m3_to_R !< A constant that translates kilograms per meter cubed to the units of density.
 
   ! These are useful combinations of the fundamental scale conversion factors above.
   real :: Z_to_L !< Convert vertical distances to lateral lengths
@@ -32,6 +34,7 @@ module MOM_unit_scaling
   real :: m_to_Z_restart = 0.0 !< A copy of the m_to_Z that is used in restart files.
   real :: m_to_L_restart = 0.0 !< A copy of the m_to_L that is used in restart files.
   real :: s_to_T_restart = 0.0 !< A copy of the s_to_T that is used in restart files.
+  real :: kg_m3_to_R_restart = 0.0 !< A copy of the kg_m3_to_R that is used in restart files.
 end type unit_scale_type
 
 contains
@@ -44,8 +47,8 @@ subroutine unit_scaling_init( param_file, US )
   ! This routine initializes a unit_scale_type structure (US).
 
   ! Local variables
-  integer :: Z_power, L_power, T_power
-  real    :: Z_rescale_factor, L_rescale_factor, T_rescale_factor
+  integer :: Z_power, L_power, T_power, R_power
+  real    :: Z_rescale_factor, L_rescale_factor, T_rescale_factor, R_rescale_factor
   ! This include declares and sets the variable "version".
 # include "version_variable.h"
   character(len=16) :: mdl = "MOM_unit_scaling"
@@ -69,12 +72,18 @@ subroutine unit_scaling_init( param_file, US )
                  "An integer power of 2 that is used to rescale the model's "//&
                  "intenal units of time.  Valid values range from -300 to 300.", &
                  units="nondim", default=0, debuggingParam=.true.)
+  call get_param(param_file, mdl, "R_RESCALE_POWER", R_power, &
+                 "An integer power of 2 that is used to rescale the model's "//&
+                 "intenal units of density.  Valid values range from -300 to 300.", &
+                 units="nondim", default=0, debuggingParam=.true.)
   if (abs(Z_power) > 300) call MOM_error(FATAL, "unit_scaling_init: "//&
                  "Z_RESCALE_POWER is outside of the valid range of -300 to 300.")
   if (abs(L_power) > 300) call MOM_error(FATAL, "unit_scaling_init: "//&
                  "L_RESCALE_POWER is outside of the valid range of -300 to 300.")
   if (abs(T_power) > 300) call MOM_error(FATAL, "unit_scaling_init: "//&
                  "T_RESCALE_POWER is outside of the valid range of -300 to 300.")
+  if (abs(R_power) > 300) call MOM_error(FATAL, "unit_scaling_init: "//&
+                 "R_RESCALE_POWER is outside of the valid range of -300 to 300.")
 
   Z_rescale_factor = 1.0
   if (Z_power /= 0) Z_rescale_factor = 2.0**Z_power
@@ -91,6 +100,11 @@ subroutine unit_scaling_init( param_file, US )
   US%T_to_s = 1.0 * T_rescale_factor
   US%s_to_T = 1.0 / T_rescale_factor
 
+  R_rescale_factor = 1.0
+  if (R_power /= 0) R_rescale_factor = 2.0**R_power
+  US%R_to_kg_m3 = 1.0 * R_rescale_factor
+  US%kg_m3_to_R = 1.0 / R_rescale_factor
+
   ! These are useful combinations of the fundamental scale conversion factors set above.
   US%Z_to_L = US%Z_to_m * US%m_to_L
   US%L_to_Z = US%L_to_m * US%m_to_Z
@@ -111,6 +125,7 @@ subroutine fix_restart_unit_scaling(US)
   US%m_to_Z_restart = US%m_to_Z
   US%m_to_L_restart = US%m_to_L
   US%s_to_T_restart = US%s_to_T
+  US%kg_m3_to_R_restart = US%kg_m3_to_R
 
 end subroutine fix_restart_unit_scaling