Add ensemble functionality (#259)

William-gregory · web-flow · commit c287b24d5d2b · 2026-05-29T14:14:22.000-04:00
This commit adds some functionalities needed for running ensemble experiments with SIS2.

The changes to SIS_get_input.F90 mean that the user can run a perturbed sea ice physics ensemble by passing unique SIS_override files to SIS_input_nml via:

parameter_filename = 'INPUT/SIS_input','INPUT/SIS_layout','INPUT/SIS_override_%E'

The changes to SIS_sum_output.F90 mean that a seaice.stats file will be created for each ensemble member, allowing the user to track conservation statistics for each member.

The changes to SIS_fixed_initialization.F90 mean that a sea_ice_geometry file will not be created for each ensemble member, but only for the first one. This was needed because the simulation crashes during initialization when running a large (30-member) perturbed sea ice physics ensemble from a cold start (input_filename = 'n'). It seemed like all the ensemble members were trying to read/write the same sea_ice_geometry file. This has been fixed by only having the first ensemble member write its version of the sea_ice_geometry file.
diff --git a/src/SIS_fixed_initialization.F90 b/src/SIS_fixed_initialization.F90
@@ -14,7 +14,7 @@ module SIS_fixed_initialization
 use MOM_error_handler, only   : callTree_enter, callTree_leave, callTree_waypoint
 use MOM_file_parser, only     : get_param, read_param, log_param, log_version, param_file_type
 use MOM_grid_initialize, only : initialize_masks, set_grid_metrics
-use MOM_io, only              : slasher
+use MOM_io, only              : slasher, get_filename_appendix
 ! use MOM_shared_initialization, only : MOM_shared_init_init
 use MOM_shared_initialization, only : MOM_initialize_rotation, MOM_calculate_grad_Coriolis
 use MOM_shared_initialization, only : initialize_topography_from_file, apply_topography_edits_from_file
@@ -48,6 +48,7 @@ subroutine SIS_initialize_fixed(G, US, PF, write_geom, output_dir, OBC)
   character(len=200) :: inputdir   ! The directory where NetCDF input files are.
   character(len=200) :: config
   character(len=40)  :: mdl = "SIS_initialize_fixed" ! This module's name.
+  character(len=32) :: filename_appendix = "" !fms appendix to filename for ensemble runs
   logical :: debug
 ! This include declares and sets the variable "version".
 #include "version_variable.h"
@@ -126,8 +127,15 @@ subroutine SIS_initialize_fixed(G, US, PF, write_geom, output_dir, OBC)
   call initialize_grid_rotation_angle(G, PF)
 
   ! Write out all of the grid data used by this run.
-  if (write_geom) call write_ocean_geometry_file(G, PF, output_dir, &
-                                                 geom_file="sea_ice_geometry", US=US)
+  if (write_geom) then
+    !query fms_io if there is a filename_appendix (for ensemble runs)
+    call get_filename_appendix(filename_appendix)
+    if ((len_trim(filename_appendix) == 0) .or. (filename_appendix == "ens_01")) then
+      call write_ocean_geometry_file(G, PF, output_dir, &
+                geom_file="sea_ice_geometry", US=US)
+    endif
+    
+  endif
 
   call callTree_leave('SIS_initialize_fixed()')
 
diff --git a/src/SIS_get_input.F90 b/src/SIS_get_input.F90
@@ -29,13 +29,15 @@ module SIS_get_input
 
 !> Get_SIS_input reads the SIS namelist entries to see if the run is to be started from
 !! a saved restart file, and get the names of the parameter files, I/O directories.
-subroutine Get_SIS_Input(param_file, dirs, check_params, component)
+subroutine Get_SIS_Input(param_file, dirs, check_params, component, ensemble_num)
   type(param_file_type), optional, intent(out) :: param_file !< A structure to parse for run-time parameters
   type(directories),     optional, intent(out) :: dirs         !< Container for paths and parameter file names.
   logical,               optional, intent(in)  :: check_params !< If present and False will stop error checking for
                                                                !! run-time parameters.
   character(len=*),      optional, intent(in)  :: component    !< An alternate component name, the default is "SIS"
 
+  integer,               optional, intent(in)  :: ensemble_num !< The ensemble id of the current member
+
 !    See if the run is to be started from saved conditions, and get  !
 !  the names of the I/O directories and initialization file.  This   !
 !  subroutine also calls the subroutine that allows run-time changes !
@@ -67,20 +69,27 @@ subroutine Get_SIS_Input(param_file, dirs, check_params, component)
   enddo
 10 call close_file(unit)
   if (present(dirs)) then
-    dirs%output_directory = trim(slasher(ensembler(output_directory)))
-    dirs%restart_output_dir = trim(slasher(ensembler(restart_output_dir)))
-    dirs%restart_input_dir = trim(slasher(ensembler(restart_input_dir)))
-    dirs%input_filename = trim(ensembler(input_filename))
+    if (present(ensemble_num)) then
+      dirs%output_directory = trim(slasher(ensembler(output_directory,ensemble_num)))
+      dirs%restart_output_dir = trim(slasher(ensembler(restart_output_dir,ensemble_num)))
+      dirs%restart_input_dir = trim(slasher(ensembler(restart_input_dir,ensemble_num)))
+      dirs%input_filename = trim(ensembler(input_filename,ensemble_num))
+    else
+      dirs%output_directory = trim(slasher(ensembler(output_directory)))
+      dirs%restart_output_dir = trim(slasher(ensembler(restart_output_dir)))
+      dirs%restart_input_dir = trim(slasher(ensembler(restart_input_dir)))
+      dirs%input_filename = trim(ensembler(input_filename))
+    endif
   endif
 
   comp = "SIS" ; if (present(component)) comp = trim(adjustl(component))
 
   if (present(param_file)) then
     output_dir = trim(slasher(ensembler(output_directory)))
     valid_param_files = 0
-    do io = 1, npf
+    do io = 1, npf  
       if (len_trim(trim(parameter_filename(io))) > 0) then
-        call open_param_file(trim(parameter_filename(io)), param_file, &
+        call open_param_file(trim(ensembler(parameter_filename(io),ensemble_num)), param_file, &
                              check_params, component=comp, &
                              doc_file_dir=output_dir)
         valid_param_files = valid_param_files + 1
@@ -92,4 +101,4 @@ subroutine Get_SIS_Input(param_file, dirs, check_params, component)
 
 end subroutine Get_SIS_Input
 
-end module SIS_get_input
+end module SIS_get_input
diff --git a/src/SIS_sum_output.F90 b/src/SIS_sum_output.F90
@@ -20,6 +20,7 @@ module SIS_sum_output
 use MOM_file_parser,   only : get_param, log_param, log_version, param_file_type
 ! use MOM_io,          only : create_file, fieldtype, flush_file, reopen_file, vardesc, write_field
 use MOM_io,            only : open_ASCII_file, APPEND_FILE, ASCII_FILE, SINGLE_FILE, WRITEONLY_FILE
+use MOM_io,            only : get_filename_appendix
 use MOM_string_functions, only : slasher
 use MOM_time_manager,  only : time_type, get_time, operator(>), operator(-)
 use MOM_time_manager,  only : get_date, get_calendar_type, NO_CALENDAR
@@ -110,6 +111,8 @@ subroutine SIS_sum_output_init(G, param_file, directory, Input_start_time, US, C
   ! Local variables
   character(len=40)  :: mdl = "SIS_sum_output" ! This module's name.
   character(len=200) :: statsfile  ! The name of the statistics file.
+  character(len=32) :: filename_appendix = "" !fms appendix to filename for ensemble runs
+  
   ! This include declares and sets the variable "version".
 # include "version_variable.h"
 
@@ -146,8 +149,15 @@ subroutine SIS_sum_output_init(G, param_file, directory, Input_start_time, US, C
                  "The file to use to write the globally integrated "//&
                  "statistics.", default="seaice.stats")
 
-  CS%statsfile = trim(slasher(directory))//trim(statsfile)
+  !query fms_io if there is a filename_appendix (for ensemble runs)
+  call get_filename_appendix(filename_appendix)
+  if (len_trim(filename_appendix) > 0) then
+    CS%statsfile = trim(slasher(directory))//trim(statsfile)//'.'//trim(filename_appendix)
+  else
+    CS%statsfile = trim(slasher(directory))//trim(statsfile)
+  endif
   call log_param(param_file, mdl, "output_path/STATISTICS_FILE", CS%statsfile)
+
 #ifdef STATSLABEL
   CS%statsfile = trim(CS%statsfile)//"."//trim(adjustl(STATSLABEL))
 #endif
