C $Header: /u/gcmpack/MITgcm/pkg/dic/car_flux_omega_top.F,v 1.7 2008/04/07 20:31:16 dfer Exp $
C $Name: $
#include "DIC_OPTIONS.h"
CBOP
C !ROUTINE: CAR_FLUX
C !INTERFACE: ==========================================================
SUBROUTINE CAR_FLUX_OMEGA_TOP( bioac, cflux,
I bi,bj,imin,imax,jmin,jmax,
I myIter,myTime,myThid)
C !DESCRIPTION:
C Calculate carbonate fluxes
C HERE ONLY HAVE DISSOLUTION WHEN OMEGA < 1.0
C Karsten Friis and Mick Follows Sep 2004
C !USES: ===============================================================
IMPLICIT NONE
#include "SIZE.h"
#include "DYNVARS.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GRID.h"
#include "DIC_VARS.h"
C !INPUT PARAMETERS: ===================================================
C myThid :: thread number
C myIter :: current timestep
C myTime :: current time
C bioac :: biological productivity
INTEGER myIter
_RL myTime
INTEGER myThid
_RL bioac(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr)
INTEGER imin, imax, jmin, jmax, bi, bj
C !OUTPUT PARAMETERS: ===================================================
C cflux :: carbonate flux
_RL cflux(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr)
#ifdef ALLOW_PTRACERS
#ifdef DIC_BIOTIC
C !LOCAL VARIABLES: ====================================================
C i,j,k :: loop indices
c ko :: loop-within-loop index
c caexport :: flux of carbonate from base each "productive"
c layer
c depth_u, depth_l :: depths of upper and lower interfaces
c flux_u, flux_l :: flux through upper and lower interfaces
_RL caexport(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
INTEGER I,J,k, ko
_RL flux_u, flux_l
c variables for calcium carbonate dissolution
_RL KierRate
_RL DissolutionRate
_RL WsinkPIC
INTEGER iflx
_RL dumrate
c diagnostics
c _RL exp_tot
c _RL flx_tot
c integer knum
c _RL omeg_bot
c _RL tmp
CEOP
c flag to either remineralize in bottom or top layer if flux
c reaches bottom layer 0=bottom, 1=top
iflx=1
c set some nominal particulate sinking rate
c try 100m/day
WsinkPIC = 100/86400.0
c calculate carbonate flux from base of each nlev
DO j=jmin,jmax
DO i=imin,imax
c exp_tot=0
do k=1,nR
cflux(i,j,k)=0.d0
enddo
DO k=1,nLev
if (hFacC(i,j,k,bi,bj).gt.0.d0) then
caexport(i,j)= R_CP*rain_ratio(i,j,bi,bj)*bioac(i,j,k)*
& (1.0-DOPfraction)*drF(k)*hFacC(i,j,k,bi,bj)
c exp_tot=exp_tot+caexport(i,j)
c calculate flux to each layer from base of k
Do ko=k+1,Nr
if (hFacC(i,j,ko,bi,bj).gt.0.d0) then
if (ko .eq. k+1) then
flux_u = caexport(i,j)
else
flux_u = flux_l
endif
C flux through lower face of cell
if (omegaC(i,j,ko,bi,bj) .gt. 1.0) then
flux_l = flux_u
c if at bottom, remineralize remaining flux
if (ko.eq.Nr.or.hFacC(i,j,ko+1,bi,bj).eq.0.d0) then
if (iflx.eq.1) then
c ... at surface
cflux(i,j,1)=cflux(i,j,1)+
& ( (flux_l)/(drF(1)*hFacC(i,j,1,bi,bj)) )
else
c ... at bottom
flux_l=0.d0
endif
endif
else
c if dissolution, then use rate from Kier (1980) Geochem. Cosmochem. Acta
c Kiers dissolution rate in % per day
KierRate = 7.177* ((1.0-omegaC(i,j,ko,bi,bj))**4.54)
c convert to per s
c Karsten finds Kier value not in 0/0 after all... therefore drop 100 factor
c DissolutionRate = KierRate/(100.0*86400.0)
DissolutionRate = KierRate/(86400.0)
c flux_l = flux_u*(1.0-DissolutionRate*drF(k)/WsinkPIC)
c Karstens version
c - gives NaNs (because using kierrate, not dissolution rate)???
c flux_l = flux_u*(1.0-KierRate)**(drF(k)/WsinkPIC)
c MICKS NEW VERSION... based on vertical sinking/remin balance
dumrate = -1.0d0*DissolutionRate*drF(ko)*
& hFacC(i,j,ko,bi,bj)/WsinkPIC
flux_l = flux_u*exp(dumrate)
c TEST ............................
c if(i .eq. 76 .and. j .eq. 36)then
c write(6,*)'k,flux_l/flux_u',ko,(flux_l/flux_u)
c write(6,*)'K, KierRate, drF(k), drF(ko), WsinkPIC,OmegaC'
c write(6,*)ko,KierRate,drF(k),drF(ko),WsinkPIC,
c & omegaC(i,j,ko,bi,bj)
c endif
c TEST ............................
c no flux to ocean bottom
if (ko.eq.Nr.or.hFacC(i,j,ko+1,bi,bj).eq.0.d0)
& flux_l=0.d0
endif
c flux divergence
cflux(i,j,ko)=cflux(i,j,ko) +
& ( (flux_u-flux_l)/(drF(ko)*hFacC(i,j,ko,bi,bj)) )
c TEST ............................
c if(i .eq. 76 .and. j .eq. 36)then
c write(6,*)'k,flux_l/flux_u',ko,(flux_l/flux_u)
c write(6,*)'k,flux_l,cflux ',ko,flux_l,cflux(i,j,ko)
c endif
c TEST ............................
else
c if no layer below initial layer, remineralize
if (ko.eq.k+1) then
if (iflx.eq.1.and.omegaC(i,j,k,bi,bj) .gt. 1.d0) then
c ... at surface
cflux(i,j,1)=cflux(i,j,1)
& +bioac(i,j,k)*(1.0-DOPfraction)*
& R_CP*rain_ratio(i,j,bi,bj)
& *drF(k)*hFacC(i,j,k,bi,bj)/
& (drF(1)*hFacC(i,j,1,bi,bj) )
else
c ... at bottom
cflux(i,j,k)=cflux(i,j,k)
& +bioac(i,j,k)*(1.0-DOPfraction)*
& R_CP*rain_ratio(i,j,bi,bj)
endif
endif
endif
ENDDO
endif
ENDDO
c diagnostic
c flx_tot=0
c k=0
c do k=1,nR
c flx_tot=flx_tot+cflux(i,j,k)*drF(k)*hFacC(i,j,k,bi,bj)
c if (hFacC(i,j,k,bi,bj).gt.0) then
c knum=k
c omeg_bot=omegaC(i,j,k,bi,bj)
c endif
c enddo
c if (hFacC(i,j,k,bi,bj).gt.0) then
c tmp=abs(exp_tot-flx_tot)
c if (tmp>1e-20) then
c print*,'QQ car_flux', knum,
c & omeg_bot, exp_tot, flx_tot, exp_tot-flx_tot
c endif
c endif
c end diagnostic
ENDDO
ENDDO
c
#endif
#endif
RETURN
END