--- MITgcm/pkg/dic/dic_surfforcing.F	2005/08/25 22:32:44	1.9
+++ MITgcm/pkg/dic/dic_surfforcing.F	2007/08/13 02:29:40	1.14
@@ -1,4 +1,4 @@
-C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/pkg/dic/dic_surfforcing.F,v 1.9 2005/08/25 22:32:44 stephd Exp $
+C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/pkg/dic/dic_surfforcing.F,v 1.14 2007/08/13 02:29:40 dfer Exp $
 C $Name:  $
 
 #include "DIC_OPTIONS.h"
@@ -9,7 +9,7 @@
 C !ROUTINE: DIC_SURFFORCING
 
 C !INTERFACE: ==========================================================
-      SUBROUTINE DIC_SURFFORCING( PTR_CO2 , GDC, 
+      SUBROUTINE DIC_SURFFORCING( PTR_CO2 , PTR_ALK, PTR_PO4, GDC, 
      I           bi,bj,imin,imax,jmin,jmax,
      I           myIter,myTime,myThid)
 
@@ -26,10 +26,6 @@
 #include "GRID.h"
 #include "FFIELDS.h"
 #include "DIC_ABIOTIC.h"
-#ifdef DIC_BIOTIC
-#include "PTRACERS_SIZE.h"
-#include "PTRACERS.h"
-#endif
 
 C !INPUT PARAMETERS: ===================================================
 C  myThid               :: thread number
@@ -39,6 +35,8 @@
       INTEGER myIter, myThid
       _RL myTime
       _RL  PTR_CO2(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr)
+      _RL  PTR_ALK(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr)
+      _RL  PTR_PO4(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr)
       INTEGER iMin,iMax,jMin,jMax, bi, bj
 
 C !OUTPUT PARAMETERS: ===================================================
@@ -65,24 +63,28 @@
 
       kLev=1
 
+c if coupled to atmsopheric model, use the
+c Co2 value passed from the coupler
+#ifndef USE_ATMOSCO2
 C PRE-INDUSTRIAL STEADY STATE pCO2 = 278.0 ppmv
        DO j=1-OLy,sNy+OLy
         DO i=1-OLx,sNx+OLx
            AtmospCO2(i,j,bi,bj)=278.0d-6
         ENDDO
        ENDDO
+#endif
 
 
 C =================================================================
 C determine inorganic carbon chem coefficients
-        DO j=1-OLy,sNy+OLy
-         DO i=1-OLx,sNx+OLx
+        DO j=jmin,jmax
+         DO i=imin,imax
 
 #ifdef DIC_BIOTIC
 cQQQQ check ptracer numbers
-             surfalk(i,j) = PTRACER(i,j,klev,bi,bj,2)
+             surfalk(i,j) = PTR_ALK(i,j,klev)
      &                          * maskC(i,j,kLev,bi,bj)
-             surfphos(i,j)  = PTRACER(i,j,klev,bi,bj,3)
+             surfphos(i,j)  = PTR_PO4(i,j,klev)
      &                          * maskC(i,j,kLev,bi,bj)
 #else
              surfalk(i,j) = 2.366595 * salt(i,j,kLev,bi,bj)/gsm_s
@@ -101,9 +103,9 @@
 
 c pCO2 solver...
 C$TAF LOOP = parallel
-       DO j=1-OLy,sNy+OLy
+       DO j=jmin,jmax
 C$TAF LOOP = parallel
-        DO i=1-OLx,sNx+OLx
+        DO i=imin,imax
 
           IF(maskC(i,j,kLev,bi,bj) .NE. 0.)THEN
             CALL CALC_PCO2_APPROX(
@@ -122,8 +124,8 @@
         ENDDO
        ENDDO
 
-       DO j=1-OLy,sNy+OLy
-        DO i=1-OLx,sNx+OLx
+       DO j=jmin,jmax
+        DO i=imin,imax
 
             IF (maskC(i,j,kLev,bi,bj).NE.0.) THEN
 C calculate SCHMIDT NO. for CO2
@@ -134,12 +136,23 @@
      &          + sca4 * theta(i,j,kLev,bi,bj)*theta(i,j,kLev,bi,bj) 
      &                *theta(i,j,kLev,bi,bj)
 
+c
+#ifdef USE_PLOAD
+C Convert anomalous pressure pLoad (in Pa) from atmospheric model
+C to total pressure (in Atm)
+C Note: it is assumed the reference atmospheric pressure is 1Atm=1013mb
+C       rather than the actual ref. pressure from Atm. model so that on
+C       average AtmosP is about 1 Atm.
+               AtmosP(i,j,bi,bj)= 1. _d 0 + pLoad(i,j,bi,bj)/Pa2Atm
+#endif
+
 C Determine surface flux (FDIC)
 C first correct pCO2at for surface atmos pressure
               pCO2sat(i,j) = 
      &          AtmosP(i,j,bi,bj)*AtmospCO2(i,j,bi,bj)
 c find exchange coefficient
 c  account for schmidt number and and varible piston velocity
+              pisvel(i,j,bi,bj)  =0.337*wind(i,j,bi,bj)**2/3.6d5
               Kwexch(i,j) =
      &             pisvel(i,j,bi,bj)
      &             / sqrt(SchmidtNoDIC(i,j)/660.0)
@@ -184,8 +197,8 @@
          ENDDO
 
 C update tendency      
-         DO j=1-OLy,sNy+OLy
-          DO i=1-OLx,sNx+OLx
+         DO j=jmin,jmax
+          DO i=imin,imax
            GDC(i,j)= maskC(i,j,kLev,bi,bj)*recip_drF(kLev)*
      &                     recip_hFacC(i,j,kLev,bi,bj)*(
      &                    FluxCO2(i,j,bi,bj) + VirtualFlux(i,j)