[Dart-dev] DART/branches Revision: 12176

[dart at ucar.edu]

nancy at ucar.edu
2017-12-05 10:54:38 -0700 (Tue, 05 Dec 2017)
256
added a perturb routine where you can specify only
certain quantities and an amplitude per quantity.

also i found you can ask for the quantity directly 
back from get_model_variable_indices() so i removed
a separate call to get the quantity in 2 places.




Modified: DART/branches/recam/models/cam-fv/model_mod.f90
===================================================================
--- DART/branches/recam/models/cam-fv/model_mod.f90	2017-12-05 17:05:39 UTC (rev 12175)
+++ DART/branches/recam/models/cam-fv/model_mod.f90	2017-12-05 17:54:38 UTC (rev 12176)
@@ -34,9 +34,9 @@
                                   QTY_SURFACE_PRESSURE, &
                                   QTY_TEMPERATURE, QTY_SPECIFIC_HUMIDITY, &
                                   get_index_for_quantity, get_num_quantities
-!#! use     mpi_utilities_mod
-!#! use        random_seq_mod
-use  ensemble_manager_mod,  only : ensemble_type
+use     mpi_utilities_mod,  only : my_task_id
+use        random_seq_mod,  only : random_seq_type, init_random_seq, random_gaussian
+use  ensemble_manager_mod,  only : ensemble_type, get_my_num_vars, get_my_vars
 use distributed_state_mod,  only : get_state
 use   state_structure_mod,  only : add_domain, get_dart_vector_index, get_domain_size, &
                                    get_dim_name, get_kind_index, get_num_dims, &
@@ -58,7 +58,7 @@
                                    GRID_QUAD_IRREG_SPACED_REGULAR,  &
                                    QUAD_LOCATED_CELL_CENTERS
 use     default_model_mod,  only : adv_1step, init_time, init_conditions, &
-                                   nc_write_model_vars, pert_model_copies
+                                   nc_write_model_vars
 
 implicit none
 private
@@ -70,16 +70,16 @@
 public :: static_init_model,                   &
           get_model_size,                      &
           get_state_meta_data,                 &
-          model_interpolate,                   & ! big todo
+          model_interpolate,                   & 
           shortest_time_between_assimilations, &
           nc_write_model_atts,                 &
-          write_model_time,                    & ! todo
+          write_model_time,                    & 
           read_model_time,                     &
           end_model
 
 ! code for these routines are in other modules
 public :: nc_write_model_vars,           &
-          pert_model_copies,             & ! todo
+          pert_model_copies,             & 
           adv_1step,                     &
           init_time,                     &
           init_conditions,               & 
@@ -94,6 +94,10 @@
 character(len=32 ), parameter :: revision = "$Revision$"
 character(len=128), parameter :: revdate  = "$Date$"
 
+! maximum number of fields you can list to be perturbed
+! to generate an ensemble if starting from a single state.
+integer, parameter :: MAX_PERT = 100
+
 ! model_nml namelist variables and default values
 character(len=256) :: cam_template_filename           = 'caminput.nc'
 character(len=256) :: cam_phis_filename               = 'camphis.nc'
@@ -105,6 +109,9 @@
 logical            :: use_damping_ramp_at_model_top   = .false.  
 integer            :: debug_level                     = 0
 logical            :: suppress_grid_info_in_output    = .false.
+logical            :: custom_routine_to_generate_ensemble = .false.
+character(len=32)  :: fields_to_perturb(MAX_PERT)     = "QTY_TEMPERATURE"
+real(r8)           :: perturbation_amplitude(MAX_PERT)= 0.00001_r8
 
 ! state_variables defines the contents of the state vector.
 ! each line of this input should have the form:
@@ -130,6 +137,9 @@
    no_assim_above_this_model_level, &
    use_damping_ramp_at_model_top,   &
    suppress_grid_info_in_output,    &
+   custom_routine_to_generate_ensemble, &
+   fields_to_perturb,               &
+   perturbation_amplitude,          &
    debug_level
 
 
@@ -305,9 +315,8 @@
 
 if ( .not. module_initialized ) call static_init_model
 
-call get_model_variable_indices(index_in, iloc, jloc, vloc, var_id=myvarid)
+call get_model_variable_indices(index_in, iloc, jloc, vloc, var_id=myvarid, kind_index=myqty)
 
-myqty = get_kind_index(domain_id, myvarid)
 nd = get_num_dims(domain_id, myvarid)
 
 location = get_location_from_index(iloc, jloc, vloc, myqty, nd)
@@ -1880,8 +1889,89 @@
 
 end function read_model_time
 
+!--------------------------------------------------------------------
+!> if the namelist is set to not use this custom routine, the default
+!> dart routine will add 'pert_amp' of noise to every field in the state
+!> to generate an ensemble from a single member.  if it is set to true
+!> this routine will be called.  the pert_amp will be ignored, and the
+!> given list of quantities will be perturbed by the given amplitude
+!> (which can be different for each field) to generate an ensemble.
 
+subroutine pert_model_copies(state_ens_handle, ens_size, pert_amp, interf_provided)