C $Header: /u/gcmpack/MITgcm/pkg/aim_v23/aim_surf_bc.F,v 1.20 2013/01/21 21:49:33 jmc Exp $
C $Name: $
#include "AIM_OPTIONS.h"
CBOP
C !ROUTINE: AIM_SURF_BC
C !INTERFACE:
SUBROUTINE AIM_SURF_BC(
U tYear,
O aim_sWght0, aim_sWght1,
I bi, bj, myTime, myIter, myThid )
C !DESCRIPTION: \bv
C *================================================================*
C | S/R AIM_SURF_BC
C | Set surface Boundary Conditions
C | for the atmospheric physics package
C *================================================================*
c | was part of S/R FORDATE in Franco Molteni SPEEDY code (ver23).
C | For now, surface BC are loaded from files (S/R AIM_FIELDS_LOAD)
C | and imposed (= surf. forcing).
C | In the future, will add
C | a land model and a coupling interface with an ocean GCM
C *================================================================*
C \ev
C !USES:
IMPLICIT NONE
C -------------- Global variables --------------
C-- size for MITgcm & Physics package :
#include "AIM_SIZE.h"
C-- MITgcm
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GRID.h"
c #include "DYNVARS.h"
c #include "SURFACE.h"
C-- Physics package
#include "AIM_PARAMS.h"
#include "AIM_FFIELDS.h"
c #include "AIM_GRID.h"
#include "com_forcon.h"
#include "com_forcing.h"
c #include "com_physvar.h"
#include "AIM_CO2.h"
C-- Coupled to the Ocean :
#ifdef COMPONENT_MODULE
#include "CPL_PARAMS.h"
#include "ATMCPL.h"
#endif
C !INPUT/OUTPUT PARAMETERS:
C == Routine arguments ==
C tYear :: Fraction into year
C aim_sWght0 :: weight for time interpolation of surface BC
C aim_sWght1 :: 0/1 = time period before/after the current time
C bi,bj :: Tile indices
C myTime :: Current time of simulation ( s )
C myIter :: Current iteration number in simulation
C myThid :: my Thread number Id.
_RL tYear
_RL aim_sWght0, aim_sWght1
INTEGER bi, bj
_RL myTime
INTEGER myIter, myThid
CEOP
#ifdef ALLOW_AIM
C !FUNCTIONS:
C !LOCAL VARIABLES:
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C-- Local Variables originally (Speedy) in common bloc (com_forcing.h):
C-- COMMON /FORDAY/ Daily forcing fields (updated in FORDATE)
C oice1 :: sea ice fraction
C snow1 :: snow depth (mm water)
_RL oice1(NGP)
_RL snow1(NGP)
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C == Local variables ==
C i,j,k,I2,k :: Loop counters
INTEGER i,j,I2,k, nm0
_RL t0prd, tNcyc, tmprd, dTprd
_RL SDEP1, IDEP2, SDEP2, SWWIL2, RSW, soilw_0, soilw_1
_RL RSD, alb_land, oceTfreez, ALBSEA1, ALPHA, CZEN, CZEN2
_RL RZEN, ZS, ZC, SJ, CJ, TMPA, TMPB, TMPL, hlim
c _RL DALB, alb_sea
#ifdef ALLOW_AIM_CO2
#ifdef ALLOW_DIAGNOSTICS
_RL pCO2scl
#endif
#endif /* ALLOW_AIM_CO2 */
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C- Set Land-sea mask (in [0,1]) from aim_landFr to fMask1:
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
fMask1(I2,1,myThid) = aim_landFr(i,j,bi,bj)
ENDDO
ENDDO
IF (aim_useFMsurfBC) THEN
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C aim_surfForc_TimePeriod :: Length of forcing time period (e.g. 1 month)
C aim_surfForc_NppCycle :: Number of time period per Cycle (e.g. 12)
C aim_surfForc_TransRatio ::
C- define how fast the (linear) transition is from one month to the next
C = 1 -> linear between 2 midle month
C > TimePeriod/deltaT -> jump from one month to the next one
C-- Calculate weight for linear interpolation between 2 month centers
t0prd = myTime / aim_surfForc_TimePeriod
tNcyc = aim_surfForc_NppCycle
tmprd = t0prd - 0.5 _d 0 + tNcyc
tmprd = MOD(tmprd,tNcyc)
C- indices of previous month (nm0) and next month (nm1):
nm0 = 1 + INT(tmprd)
c nm1 = 1 + MOD(nm0,aim_surfForc_NppCycle)
C- interpolation weight:
dTprd = tmprd - (nm0 - 1)
aim_sWght1 = 0.5 _d 0+(dTprd-0.5 _d 0)*aim_surfForc_TransRatio
aim_sWght1 = MAX( 0. _d 0, MIN(1. _d 0, aim_sWght1) )
aim_sWght0 = 1. _d 0 - aim_sWght1
C-- Compute surface forcing at present time (linear Interp in time)
C using F.Molteni surface BC form ; fields needed are:
C 1. Sea Surface temperatures (in situ Temp. [K])
C 2. Land Surface temperatures (in situ Temp. [K])
C 3. Soil moisture (between 0-1)
C 4. Snow depth, Sea Ice : used to compute albedo (=> local arrays)
C 5. Albedo (between 0-1)
C- Surface Temperature:
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
sst1(I2,myThid) = aim_sWght0*aim_sst0(i,j,bi,bj)
& + aim_sWght1*aim_sst1(i,j,bi,bj)
stl1(I2,myThid) = aim_sWght0*aim_lst0(i,j,bi,bj)
& + aim_sWght1*aim_lst1(i,j,bi,bj)
ENDDO
ENDDO
C- Soil Water availability : (from F.M. INFORC S/R)
SDEP1 = 70. _d 0
IDEP2 = 3. _d 0
SDEP2 = IDEP2*SDEP1
SWWIL2= SDEP2*SWWIL
RSW = 1. _d 0/(SDEP1*SWCAP+SDEP2*(SWCAP-SWWIL))
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
soilw_0 = ( aim_sw10(i,j,bi,bj)
& +aim_veget(i,j,bi,bj)*
& MAX(IDEP2*aim_sw20(i,j,bi,bj)-SWWIL2, 0. _d 0)
& )*RSW
soilw_1 = ( aim_sw11(i,j,bi,bj)
& +aim_veget(i,j,bi,bj)*
& MAX(IDEP2*aim_sw21(i,j,bi,bj)-SWWIL2, 0. _d 0)
& )*RSW
soilw1(I2,myThid) = aim_sWght0*soilw_0
& + aim_sWght1*soilw_1
soilw1(I2,myThid) = MIN(1. _d 0, soilw1(I2,myThid) )
ENDDO
ENDDO
C- Set snow depth & sea-ice fraction :
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
snow1(I2) = aim_sWght0*aim_snw0(i,j,bi,bj)
& + aim_sWght1*aim_snw1(i,j,bi,bj)
oice1(I2) = aim_sWght0*aim_oic0(i,j,bi,bj)
& + aim_sWght1*aim_oic1(i,j,bi,bj)
ENDDO
ENDDO
IF (aim_splitSIOsFx) THEN
C- Split Ocean and Sea-Ice surf. temp. ; remove ice-fraction < 1 %
c oceTfreez = tFreeze - 1.9 _d 0
oceTfreez = celsius2K - 1.9 _d 0
DO J=1,NGP
sti1(J,myThid) = sst1(J,myThid)
IF ( oice1(J) .GT. 1. _d -2 ) THEN
sst1(J,myThid) = MAX(sst1(J,myThid),oceTfreez)
sti1(J,myThid) = sst1(J,myThid)
& +(sti1(J,myThid)-sst1(J,myThid))/oice1(J)
ELSE
oice1(J) = 0. _d 0
ENDIF
ENDDO
ELSE
DO J=1,NGP
sti1(J,myThid) = sst1(J,myThid)
ENDDO
ENDIF
C- Surface Albedo : (from F.M. FORDATE S/R)
c_FM DALB=ALBICE-ALBSEA
RSD=1. _d 0/SDALB
ALPHA= 2. _d 0*PI*(TYEAR+10. _d 0/365. _d 0)
#ifdef ALLOW_INSOLATION
ZS = - SIN(OBLIQ * deg2rad) * COS(ALPHA)
ZC = ASIN( ZS )
ZC = COS(ZC)
#else /* ALLOW_INSOLATION */
RZEN = COS(ALPHA) * ( -23.45 _d 0 * deg2rad)
ZC = COS(RZEN)
ZS = SIN(RZEN)
#endif /* ALLOW_INSOLATION */
DO j=1,sNy
DO i=1,sNx
c_FM SNOWC=MIN(1.,RSD*SNOW1(I,J))
c_FM ALBL=ALB0(I,J)+MAX(ALBSN-ALB0(I,J),0.0)*SNOWC
c_FM ALBS=ALBSEA+DALB*OICE1(I,J)
c_FM ALB1(I,J)=FMASK1(I,J)*ALBL+FMASK0(I,J)*ALBS
I2 = i+(j-1)*sNx
alb_land = aim_albedo(i,j,bi,bj)
& + MAX( 0. _d 0, ALBSN-aim_albedo(i,j,bi,bj) )
& *MIN( 1. _d 0, RSD*snow1(I2))
c alb_sea = ALBSEA + DALB*oice1(I2)
c alb1(I2,0,myThid) = alb_sea
c & + (alb_land - alb_sea)*fMask1(I2,1,myThid)
ALBSEA1 = ALBSEA
IF ( aim_selectOceAlbedo .EQ. 1) THEN
SJ = SIN(yC(i,j,bi,bj) * deg2rad)
CJ = COS(yC(i,j,bi,bj) * deg2rad)
TMPA = SJ*ZS
TMPB = CJ*ZC
TMPL = -TMPA/TMPB
IF (TMPL .GE. 1.0 _d 0) THEN
CZEN = 0.0 _d 0
ELSEIF (TMPL .LE. -1.0 _d 0) THEN
CZEN = (2.0 _d 0)*TMPA*PI
CZEN2= PI*((2.0 _d 0)*TMPA*TMPA + TMPB*TMPB)
CZEN = CZEN2/CZEN
ELSE
hlim = ACOS(TMPL)
CZEN = 2.0 _d 0*(TMPA*hlim + TMPB*SIN(hlim))
CZEN2= 2.0 _d 0*TMPA*TMPA*hlim
& + 4.0 _d 0*TMPA*TMPB*SIN(hlim)
& + TMPB*TMPB*( hlim + 0.5 _d 0*SIN(2.0 _d 0*hlim) )
CZEN = CZEN2/CZEN
ENDIF
ALBSEA1 = ( ( 2.6 _d 0 / (CZEN**(1.7 _d 0) + 0.065 _d 0) )
& + ( 15. _d 0 * (CZEN-0.1 _d 0) * (CZEN-0.5 _d 0)
& * (CZEN-1.0 _d 0) ) ) / 100.0 _d 0
ENDIF
alb1(I2,1,myThid) = alb_land
C_DE alb1(I2,2,myThid) = ALBSEA
alb1(I2,2,myThid) = 0.5 _d 0 * ALBSEA
& + 0.5 _d 0 * ALBSEA1
alb1(I2,3,myThid) = ALBICE
ENDDO
ENDDO
C-- else aim_useFMsurfBC
ELSE
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C- safer to initialise output argument aim_sWght0,1
C even if they are not used when aim_useFMsurfBC=F
aim_sWght1 = 0. _d 0
aim_sWght0 = 1. _d 0
C- Set surface forcing fields needed by atmos. physics package
C 1. Albedo (between 0-1)
C 2. Sea Surface temperatures (in situ Temp. [K])
C 3. Land Surface temperatures (in situ Temp. [K])
C 4. Soil moisture (between 0-1)
C Snow depth, Sea Ice (<- no need for now)
C Set surface albedo data (in [0,1]) from aim_albedo to alb1 :
IF (aim_useMMsurfFc) THEN
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
alb1(I2,1,myThid) = aim_albedo(i,j,bi,bj)
alb1(I2,2,myThid) = aim_albedo(i,j,bi,bj)
alb1(I2,3,myThid) = aim_albedo(i,j,bi,bj)
ENDDO
ENDDO
ELSE
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
alb1(I2,1,myThid) = 0.
alb1(I2,2,myThid) = 0.
alb1(I2,3,myThid) = 0.
ENDDO
ENDDO
ENDIF
C Set surface temperature data from aim_S/LSurfTemp to sst1 & stl1 :
IF (aim_useMMsurfFc) THEN
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
sst1(I2,myThid) = aim_sst0(i,j,bi,bj)
stl1(I2,myThid) = aim_sst0(i,j,bi,bj)
sti1(I2,myThid) = aim_sst0(i,j,bi,bj)
ENDDO
ENDDO
ELSE
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
sst1(I2,myThid) = 300.
stl1(I2,myThid) = 300.
sti1(I2,myThid) = 300.
ENDDO
ENDDO
ENDIF
C- Set soil water availability (in [0,1]) from aim_sw10 to soilw1 :
IF (aim_useMMsurfFc) THEN
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
soilw1(I2,myThid) = aim_sw10(i,j,bi,bj)
ENDDO
ENDDO
ELSE
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
soilw1(I2,myThid) = 0.
ENDDO
ENDDO
ENDIF
C- Set Snow depth and Sea Ice
C (not needed here since albedo is loaded from file)
DO j=1,sNy
DO i=1,sNx
I2 = i+(j-1)*sNx
oice1(I2) = 0.
snow1(I2) = 0.
ENDDO
ENDDO
C-- endif/else aim_useFMsurfBC
ENDIF
#ifdef COMPONENT_MODULE
IF ( useCoupler ) THEN
C-- take surface data from the ocean component
C to replace MxL fields (if use sea-ice) or directly AIM SST
CALL ATM_APPLY_IMPORT(
I aim_landFr,
U sst1(1,myThid), oice1,
I myTime, myIter, bi, bj, myThid )
ENDIF
#endif /* COMPONENT_MODULE */
#ifdef ALLOW_AIM_CO2
DO j=1-OLy,sNy+OLy
DO i=1-OLx,sNx+OLx
aim_CO2(i,j,bi,bj)= atm_pCO2
ENDDO
ENDDO
#ifdef ALLOW_DIAGNOSTICS
IF ( useDiagnostics ) THEN
pCO2scl = 1. _d 6
CALL DIAGNOSTICS_SCALE_FILL( aim_CO2(1-OLx,1-OLy,bi,bj),
& pCO2scl, 1, 'aim_pCO2', 1, 1, 2, bi, bj, myThid )
ENDIF
#endif /* ALLOW_DIAGNOSTICS */
#endif /* ALLOW_AIM_CO2 */
#ifdef ALLOW_LAND
IF (useLand) THEN
C- Use land model output instead of prescribed Temp & moisture
CALL AIM_LAND2AIM(
I aim_landFr, aim_veget, aim_albedo, snow1,
U stl1(1,myThid), soilw1(1,myThid), alb1(1,1,myThid),
I myTime, myIter, bi, bj, myThid )
ENDIF
#endif /* ALLOW_LAND */
#ifdef ALLOW_THSICE
IF (useThSIce) THEN
C- Use thermo. sea-ice model output instead of prescribed Temp & albedo
CALL AIM_SICE2AIM(
I aim_landFr,
U sst1(1,myThid), oice1,
O sti1(1,myThid), alb1(1,3,myThid),
I myTime, myIter, bi, bj, myThid )
ENDIF
#endif /* ALLOW_THSICE */
C-- set the sea-ice & open ocean fraction :
DO J=1,NGP
fMask1(J,3,myThid) =(1. _d 0 - fMask1(J,1,myThid))
& *oice1(J)
fMask1(J,2,myThid) = 1. _d 0 - fMask1(J,1,myThid)
& - fMask1(J,3,myThid)
ENDDO
C-- set the mean albedo :
DO J=1,NGP
alb1(J,0,myThid) = fMask1(J,1,myThid)*alb1(J,1,myThid)
& + fMask1(J,2,myThid)*alb1(J,2,myThid)
& + fMask1(J,3,myThid)*alb1(J,3,myThid)
ENDDO
C-- initialize surf. temp. change to zero:
DO k=1,3
DO J=1,NGP
dTsurf(J,k,myThid) = 0.
ENDDO
ENDDO
IF (.NOT.aim_splitSIOsFx) THEN
DO J=1,NGP
fMask1(J,3,myThid) = 0. _d 0
fMask1(J,2,myThid) = 1. _d 0 - fMask1(J,1,myThid)
ENDDO
ENDIF
#endif /* ALLOW_AIM */
RETURN
END