Implementing a new Data Assimilation Observation Operator

ROMS/Drivers/nl_roms.h

@@ -29,7 +29,7 @@
       USE mod_ncparam
       USE mod_scalars
 !
-#ifdef VERIFICATION
+#if defined VERIFICATION && defined ARCHAIC_OBS
       USE def_mod_mod,       ONLY : def_mod
 #endif
       USE close_io_mod,      ONLY : close_inp, close_out
@@ -43,7 +43,12 @@
 # endif
 #endif
 #ifdef VERIFICATION
+# ifdef MODERN_OBS
+      USE roms_hofx_mod,     ONLY : hofx_finalize
+# endif
+# ifdef ARCHAIC_OBS
       USE stats_modobs_mod,  ONLY : stats_modobs
+# endif
 #endif
       USE stdout_mod,        ONLY : Set_StdOutUnit, stdout_unit
       USE strings_mod,       ONLY : FoundError
@@ -215,6 +220,7 @@
       Nrun=1
 
 #ifdef VERIFICATION
+# ifdef ARCHAIC_OBS
 !
 !  Create NetCDF file for model solution at observation locations.
 !
@@ -227,6 +233,19 @@
           IF (FoundError(exit_flag, NoError, __LINE__, MyFile)) RETURN
         END DO
       END IF
+# endif
+# ifdef MODERN_OBS
+!
+!  Set switches to compute and write model at observation locations.
+!
+      IF (Nrun.eq.1) THEN
+        DO ng=1,Ngrids
+          LdefMOD(ng)=.TRUE.
+          wrtNLmod(ng)=.TRUE.
+          wrtObsScale(ng)=.TRUE.
+        END DO
+      END IF
+# endif
 #endif
 #ifdef ENKF_RESTART
 !
@@ -350,18 +369,29 @@
       END IF
 #endif
 #ifdef VERIFICATION
+# ifdef ARCHAIC_OBS
 !
 !-----------------------------------------------------------------------
 !  Compute and report model-observation comparison statistics.
 !-----------------------------------------------------------------------
 !
       DO ng=1,Ngrids
-# ifdef DISTRIBUTE
+#  ifdef DISTRIBUTE
         CALL stats_modobs (ng, MyRank)
-# else
+#  else
         CALL stats_modobs (ng, -1)
-# endif
+#  endif
       END DO
+# endif
+# ifdef MODERN_OBS
+!
+!-----------------------------------------------------------------------
+!  Finalize model at observation locations, H(x). Then, write ouput
+!  enhanced NetCDF-4 files.
+!-----------------------------------------------------------------------
+!
+      CALL hofx_finalize (iNLM)
+# endif
 #endif
 !
 !-----------------------------------------------------------------------

ROMS/External/s4dvar.in

@@ -434,7 +434,7 @@ Sigma_max(isTvar) == 0.33d0   0.056d0  ! 1:NT tracers maximum STD
                    F   F   F   F
 
 ! Input model, initial conditions, boundary conditions, and surface forcing
-! standard deviation file names, [1:Ngrids].
+! standard deviation filenames, [1:Ngrids].
 
        STDnameM == roms_std_m.nc
        STDnameI == roms_std_i.nc
@@ -443,40 +443,42 @@ Sigma_max(isTvar) == 0.33d0   0.056d0  ! 1:NT tracers maximum STD
 
 ! If computing the standard deviation from the background (prior) state
 ! vector as an alternative to climatological values read from the
-! input NetCDF file, enter output standard deviation file name,
+! input NetCDF file, enter output standard deviation filename,
 ! [1:Ngrids].
 
        STDnameC == roms_std_c.nc
 
 ! Input/output model, initial conditions, boundary conditions, and surface
-! forcing error covariance normalization factors file name, [1:Ngrids].
+! forcing error covariance normalization factors filename, [1:Ngrids].
 
        NRMnameM == roms_nrm_m.nc
        NRMnameI == roms_nrm_i.nc
        NRMnameB == roms_nrm_b.nc
        NRMnameF == roms_nrm_f.nc
 
-! Input/output observation file name, [1:Ngrids].
+! Input observation filename(s), [1:Ngrids].
+
+      NOBSFILES =  1
 
         OBSname == roms_obs.nc
 
-! Input/output Hessian eigenvectors file name, [1:Ngrids].
+! Input/output Hessian eigenvectors filename, [1:Ngrids].
 
         HSSname == roms_hss.nc
 
-! Input/output Lanczos vectors file name, [1:Ngrids].
+! Input/output Lanczos vectors filename, [1:Ngrids].
 
         LCZname == roms_lcz.nc
 
-! Output time-evolved Lanczos vectors file name, [1:Ngrids].
+! Output time-evolved Lanczos vectors filename, [1:Ngrids].
 
         LZEname == roms_lze.nc
 
-! Output model data at observation locations file name, [1:Ngrids].
+! Output model data at observation locations filename, [1:Ngrids].
 
         MODname == roms_mod.nc
 
-! Output posterior error covariance matrix file name, [1:Ngrids].
+! Output posterior error covariance matrix filename, [1:Ngrids].
 
         ERRname == roms_err.nc
 
@@ -487,7 +489,7 @@ Sigma_max(isTvar) == 0.33d0   0.056d0  ! 1:NT tracers maximum STD
        OIFnameA == roms_oif_a.nc
        OIFnameB == roms_oif_b.nc
 
-! Input coarser grid increment file name, [1:Ngrids]. It is used in
+! Input coarser grid increment filename, [1:Ngrids]. It is used in
 ! mixed-resolution split 4D-Var for regridding (coarse-to-fine), where
 ! the inner loops are run at lower resolution to accelerate the computations.
 
@@ -1028,50 +1030,60 @@ Sigma_max(isTvar) == 0.33d0   0.056d0  ! 1:NT tracers maximum STD
 !  Input/Output NetCDF files (a string with a maximum of 256 characters).
 !------------------------------------------------------------------------------
 !
+!  NOBSFILES      Number of observation files, usually NOBSFILES=1.
+!
+!  OBSname        Input/Output observations data filename(s).
+!
+!                 Users can utilize the original native 4D-Var NetCDF file,
+!                 which consolidates all observations into a single vector
+!                 sorted in ascending order of time. As the observation
+!                 operators and filters become increasingly complex,
+!                 separating the observations into multiple files can be
+!                 beneficial. Alternatively, IODA enhanced-NetCDF4 files
+!                 with "Groups" are also acceptable.
+!
 !  STDnameM       Input model error covariance
-!                   standard deviation file name.
+!                   standard deviation filename.
 !
 !  STDnameI       Input initial conditions error covariance
-!                   standard deviation file name.
+!                   standard deviation filename.
 !
 !  STDnameB       Input open boundary conditions error covariance
-!                   standard deviation file name.
+!                   standard deviation filename.
 !
 !  STDnameF       Input surface forcing error covariance
-!                   standard deviation file name.
+!                   standard deviation filename.
 !
-!  STDnameC       Output standard deviation file name
+!  STDnameC       Output standard deviation filename
 !                   computed from  background (prior) state
 !
 !  NRMnameM       Input/output model error covariance
-!                   normalization factors file name.
+!                   normalization factors filename.
 !
 !  NRMnameI       Input/output initial conditions error covariance
-!                   normalization factors file name.
+!                   normalization factors filename.
 !
 !  NRMnameB       Input/output open boundary conditions error covariance
-!                   normalization factors file name.
+!                   normalization factors filename.
 !
 !  NRMnameF       Input/output surface forcing error covariance
-!                   normalization factors file name.
-!
-!  OBSname        Input/Output observations data file name.
+!                   normalization factors filename.
 !
-!  HSSname        Input/Output Hessian eigenvectors file name.
+!  HSSname        Input/Output Hessian eigenvectors filename.
 !
-!  LCZname        Input/output Lanczos vectors file name.
+!  LCZname        Input/output Lanczos vectors filename.
 !
-!  LZEname        Output time-evolved Lanczos vectors file name.
+!  LZEname        Output time-evolved Lanczos vectors filename.
 !
-!  MODname        Output model data at observations locations file name.
+!  MODname        Output model data at observations locations filename.
 !
-!  ERRname        Output posterior error covariance matrix file name.
+!  ERRname        Output posterior error covariance matrix filename.
 !
-! Input coarser grid increment file name, [1:Ngrids]. It is used in
+! Input coarser grid increment filename, [1:Ngrids]. It is used in
 ! mixed-resolution split 4D-Var for regridding (coarse-to-fine), where
 ! the inner loops are run at lower resolution to accelerate the computations.
 !
-!  INCname        Coarse grid increment file name.
+!  INCname        Coarse grid increment filename.
 !
 ! Input forcing filenames at observation locations for computing observations
 ! impacts during the analysis-forecast cycle when RBL4DVAR_FCT_SENSITIVITY and

ROMS/Modules/mod_iounits.F

@@ -234,7 +234,6 @@ MODULE mod_iounits
       TYPE(T_IO), allocatable :: LZE(:)     ! evolved Lanczos vectors
       TYPE(T_IO), allocatable :: NRM(:,:)   ! normalization
       TYPE(T_IO), allocatable :: NUD(:)     ! nudging coefficients
-      TYPE(T_IO), allocatable :: OBS(:)     ! observations
 #if defined RBL4DVAR_FCT_SENSITIVITY && defined OBS_SPACE
       TYPE(T_IO), allocatable :: OIFA(:)    ! observation impacts, A
       TYPE(T_IO), allocatable :: OIFB(:)    ! observation impacts, B
@@ -285,6 +284,13 @@ MODULE mod_iounits
 #endif
       TYPE(T_IO), allocatable :: FRC(:,:)
 !
+!  Input observations data.
+!
+      integer, allocatable :: nOBSfiles(:)
+!
+      TYPE(T_IO), allocatable :: OBS(:)
+      TYPE(T_IO), allocatable :: OBS2(:,:)
+!
 !  Error messages.
 !
       character (len=50), dimension(9) :: Rerror =                      &
@@ -509,6 +515,9 @@ SUBROUTINE allocate_iounits (Ngrids)
       IF (.not.allocated(nFfiles)) THEN
         allocate ( nFfiles(Ngrids) )
       END IF
+      IF (.not.allocated(nOBSfiles)) THEN
+        allocate ( nOBSfiles(Ngrids) )
+      END IF
 !
 !-----------------------------------------------------------------------
 !  Initialize I/O NetCDF files ID to close state.
@@ -566,6 +575,7 @@ SUBROUTINE allocate_iounits (Ngrids)
         nBCfiles(ng)=-1
         nCLMfiles(ng)=-1
         nFfiles(ng)=-1
+        nOBSfiles(ng)=-1
       END DO
 !
 !-----------------------------------------------------------------------