Changeset 11932 for branches/UKMO/dev_r5518_obs_oper_update_sit/NEMOGCM/NEMO/OPA_SRC/OBS/obs_oper.F90

Timestamp:

2019-11-19T18:45:16+01:00 (4 years ago)

Author:

dcarneir

Message:

Changes in OBS and SBC routines for sea ice thickness data assimilation

File:

• branches/UKMO/dev_r5518_obs_oper_update_sit/NEMOGCM/NEMO/OPA_SRC/OBS/obs_oper.F90 (modified) (2 diffs)

branches/UKMO/dev_r5518_obs_oper_update_sit/NEMOGCM/NEMO/OPA_SRC/OBS/obs_oper.F90

@@ -37 +37 @@
    USE obs_grid,      ONLY : & 
       & obs_level_search     
+#if defined key_cice
+   USE ice_constants, ONLY : &    ! For conversion from sea ice freeboard to thickness
+      & rhos, rhoi, rhow
+#endif
 
    IMPLICIT NONE
@@ -874 +878 @@
          
          IF ( surfdataqc%lclim ) surfdataqc%rclm(jobs,1) = zclm(1)
+
+         IF ( TRIM(surfdataqc%cvars(1)) == 'FBD' ) THEN
+            ! Convert radar freeboard to true freeboard (add 1/4 snow depth; 1/4 based on ratio of speed of light in vacuum compared to snow (3.0e8 vs 2.4e8 m/s))
+            surfdataqc%rext(jobs,1) = surfdataqc%robs(jobs,1) 
+            surfdataqc%robs(jobs,1) = surfdataqc%rext(jobs,1) + 0.25*surfdataqc%rext(jobs,2)
+            ! If the corrected freeboard observation is outside -0.3 to 3.0 m (CPOM) then set the QC flag to bad
+            IF ((surfdataqc%robs(jobs,1) < -0.3) .OR. (surfdataqc%robs(jobs,1) > 3.0)) THEN
+               surfdataqc%nqc(jobs) = 4
+            ENDIF           
+            ! Convert corrected freeboard to ice thickness following Tilling et al. (2016)
+            surfdataqc%robs(jobs,1) = (surfdataqc%robs(jobs,1)*rhow + surfdataqc%rext(jobs,2)*rhos)/ &
+                                      (rhow - rhoi)
+            ! Flag any negative ice thickness values as bad
+            IF (surfdataqc%robs(jobs,1) < 0.0) THEN
+               surfdataqc%nqc(jobs) = 4
+            ENDIF                                     
+         ENDIF
          
          IF ( zext(1) == obfillflt ) THEN