Changeset 5841 for branches/NERC/dev_r5518_NOC_MEDUSA_Stable/NEMOGCM/NEMO/TOP_SRC/MEDUSA/trcdms_medusa.F90

Timestamp:

2015-10-30T12:48:06+01:00 (8 years ago)

Author:

jpalmier

Message:

JPALM --30-10-2015-- Add MOCSY and DMS to MEDUSA-NEMO3.6

File:

• branches/NERC/dev_r5518_NOC_MEDUSA_Stable/NEMOGCM/NEMO/TOP_SRC/MEDUSA/trcdms_medusa.F90 (modified) (8 diffs)

branches/NERC/dev_r5518_NOC_MEDUSA_Stable/NEMOGCM/NEMO/TOP_SRC/MEDUSA/trcdms_medusa.F90

@@ -39 +39 @@
 !
    SUBROUTINE trc_dms_medusa( chn, chd, mld, xqsr, xdin,   &  !! inputs
-     &  dms_surf, dms_andr, dms_simo, dms_aran, dms_hall )    !! outputs
+     &  dms_andr, dms_simo, dms_aran, dms_hall )              !! outputs
 !      
 !=======================================================================
@@ -70 +70 @@
       !!                    published (and different from the above)
       !!
+      !! AXY (08/07/15): amend to remove Julien's original calculation
+      !!                 as this is now superfluous; the four schemes 
+      !!                 are calculated and one is chosen to be passed
+      !!                 to the atmosphere in trc_bio_medusa
+      !!
 !=======================================================================
 
@@ -79 +84 @@
       REAL(wp), INTENT( in )    :: xqsr                 !! surface irradiance        (W/m2)
       REAL(wp), INTENT( in )    :: xdin                 !! surface DIN               (mmol N/m3)
-      REAL(wp), INTENT( inout ) :: dms_surf             !! DMS surface concentration (mol/m3) 
       REAL(wp), INTENT( inout ) :: dms_andr             !! DMS surface concentration (mol/m3) 
       REAL(wp), INTENT( inout ) :: dms_simo             !! DMS surface concentration (mol/m3) 
@@ -89 +93 @@
       !! temporary variables
       REAL(wp) ::    fq1,fq2,fq3
-!
-!! IJT (30/03/13): DMS calc needs this
-!! Julien : in Simo & Dachs, GBC, 2002, DMS is derived from 
-!!          CHL/MLD ratio in mg/m4 (i.e. CHL is in mg/m3
-!!          MLD in m).
-!!          In MEDUSA, we already have CHL in mg/m3 for both
-!!          Diatoms and non-diatoms (zchn,zchd); and mld from
-!!          NEMO (hmld) in m.
-      CHL = 0.0
-!!
-!!            CHL = mask * TT(I,J,1,PHYTO_TRACER) &
-!!     &       * c2n_p * mw_carbon / CCHL_P(I,J,1,1)
-      CHL = chn+chd                                 !! mg/m3 
-!!
-!! ------------------------------------------------
-!!  Calculate the DMS concentration in nM (nanomol/litre)
-!!   from Simo & Dachs, GBC, 2002, modified to be positive-definite
-!!   for MLD>182.536m, using DMS=90./MLD (Aranami & Tsunogai, JGR, 2004)
-!!   Multiply by 1.0E-6 to convert nM to (mol/m3)
-!!       cmr = fm(i,1)*chl/mld(i)
-!!       IF (cmr .lt. 0.02) THEN
-!!         IF (mld(i) .le. 182.536) THEN
-!!           csurf(i,astf_dms) = 1.0e-6*fm(i,1)*(-LOG(mld(i)) + 5.7)
-!!         ELSE
-!!           csurf(i,astf_dms) = 1.0e-6*fm(i,1)*(90./mld(i))
-!!         ENDIF
-!!       ELSE
-!!         csurf(i,astf_dms) = 1.0e-6*fm(i,1)*(55.8*cmr + 0.6)
-!!       ENDIF
-!!
-        cmr      = CHL / mld
-!       sw_dms   = 0.5 + SIGN( 0.5, cmr - 0.02 )
-!! Jpalm (11-08-2014)
-!! Explanation about the SIGN function :
-!! not easy to read, but maybe "more elegant and efficient")
-!! here for example: 
-!! sw_dms = 1 if cmr is greater than 0.02,
-!!          0 if cmr lower than 0.02
-!! then 
-!! if cmr < 0.02
-!!  dms_surf =  1.0e-6 * 90.0 / mld 
-!!       or  =  1.0e-6 * 5.7 - LOG(mld)
-!! and if cmr > 0.02
-!!  dms_surf = 1.0e-6 * ( 55.8 * cmr + 0.6 )
-!! what is equivalent to the IF loops formulations.
-!! difference is on the stresholds between mld = 182.536m
-!! (strange value...)
-!! and the Max function... that stay uncertain.
-!!
-!        dms_surf = 1.0e-6 * ( sw_dms *             &
-!     &  ( 55.8 * cmr + 0.6 ) + ( 1.0 - sw_dms ) *  &
-!     &  ( MAX( 90.0 / mld, 5.7 - LOG(mld) ) ) )
-!
-! AXY (12/01/15): the DMS equation donated by the UKMO does not match
-!                 that reported in Halloran et al. (2010); amend the
-!                 equations appropriately
-!
-        if (cmr .lt. 0.02) then
-           dms_surf = (-1.0 * log(mld)) + 5.7
-        else
-           dms_surf = (55.8 * cmr) + 0.6
-        endif
-!    
-        if (mld > 182.5) then
-           dms_surf = (90.0 / mld)
-        endif
-!     
-        dms_surf = 1.0e-6 * dms_surf
-
 ! 
 !=======================================================================
@@ -163 +98 @@
 ! AXY (13/03/15): per remarks above, the following calculations estimate
 !                 DMS using all of the schemes examined for UKESM1
+!
+      CHL = 0.0
+      CHL = chn+chd                                 !! mg/m3 
+      cmr = CHL / mld
 !
 ! AXY (13/03/15): Anderson et al. (2001)
@@ -180 +119 @@
 !
 ! AXY (13/03/15): Simo & Dachs (2002)
-        cmr = CHL / mld
         fq1 = (-1 * log(mld)) + 5.7
         fq2 = (55.8 * cmr) + 0.6
@@ -191 +129 @@
 !           
 ! AXY (13/03/15): Aranami & Tsunogai (2004)
-        cmr = CHL / mld
         fq1 = 60.0 / mld
         fq2 = (55.8 * cmr) + 0.6
@@ -202 +139 @@
 !        
 ! AXY (13/03/15): Halloran et al. (2010)
-        cmr = CHL / mld
         fq1 = (-1 * log(mld)) + 5.7
         fq2 = (55.8 * cmr) + 0.6