C $Header: /u/gcmpack/MITgcm/pkg/thsice/thsice_get_exf.F,v 1.24 2014/05/02 22:15:26 jmc Exp $
C $Name: $
#include "THSICE_OPTIONS.h"
#ifdef ALLOW_EXF
#include "EXF_OPTIONS.h"
#endif
CBOP
C !ROUTINE: THSICE_GET_EXF
C !INTERFACE:
SUBROUTINE THSICE_GET_EXF(
I bi, bj, it2,
I iMin,iMax, jMin,jMax,
I icFlag, hSnow1, tsfCel,
O flxExcSw, dFlxdT, evapLoc, dEvdT,
I myTime, myIter, myThid )
C !DESCRIPTION: \bv
C *==========================================================*
C | S/R THSICE_GET_EXF
C *==========================================================*
C | Interface S/R : get Surface Fluxes from pkg EXF
C *==========================================================*
C \ev
C !USES:
IMPLICIT NONE
C == Global data ==
#include "SIZE.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#ifdef ALLOW_EXF
# include "EXF_CONSTANTS.h"
# include "EXF_PARAM.h"
# include "EXF_FIELDS.h"
#endif
#ifdef ALLOW_AUTODIFF_TAMC
# include "tamc.h"
# include "tamc_keys.h"
# include "THSICE_SIZE.h"
#endif
C !INPUT/OUTPUT PARAMETERS:
C === Routine arguments ===
C bi,bj :: tile indices
C it :: solv4temp iteration
C iMin,iMax :: computation domain: 1rst index range
C jMin,jMax :: computation domain: 2nd index range
C icFlag :: True= get fluxes at this location ; False= do nothing
C hSnow1 :: snow height [m]
C tsfCel :: surface (ice or snow) temperature (oC)
C flxExcSw :: net (downward) surface heat flux, except short-wave [W/m2]
C dFlxdT :: deriv of flx with respect to Tsf [W/m/K]
C evapLoc :: surface evaporation (>0 if evaporate) [kg/m2/s]
C dEvdT :: deriv of evap. with respect to Tsf [kg/m2/s/K]
C myTime :: current Time of simulation [s]
C myIter :: current Iteration number in simulation
C myThid :: my Thread Id number
INTEGER bi, bj
INTEGER it2
INTEGER iMin, iMax
INTEGER jMin, jMax
_RL icFlag (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL hSnow1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL tsfCel (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL flxExcSw(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL dFlxdT (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL evapLoc (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL dEvdT (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL myTime
INTEGER myIter
INTEGER myThid
CEOP
#ifdef ALLOW_EXF
#ifdef ALLOW_ATM_TEMP
#ifdef ALLOW_DOWNWARD_RADIATION
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C === Local variables ===
C hsLocal, hlLocal :: sensible & latent heat flux over sea-ice
C t0 :: virtual temperature (K)
C ssq :: saturation specific humidity (kg/kg)
C deltap :: potential temperature diff (K)
_RL hsLocal
_RL hlLocal
INTEGER iter
INTEGER i, j
_RL czol
_RL wsm ! limited wind speed [m/s] (> umin)
_RL t0 ! virtual temperature [K]
C copied from exf_bulkformulae:
C these need to be 2D-arrays for vectorizing code
C turbulent temperature scale [K]
_RL tstar (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
C turbulent humidity scale [kg/kg]
_RL qstar (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
C friction velocity [m/s]
_RL ustar (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
C neutral, zref (=10m) values of rd
_RL rdn (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL rd (1-OLx:sNx+OLx,1-OLy:sNy+OLy) ! = sqrt(Cd) [-]
_RL rh (1-OLx:sNx+OLx,1-OLy:sNy+OLy) ! = Ch / sqrt(Cd) [-]
_RL re (1-OLx:sNx+OLx,1-OLy:sNy+OLy) ! = Ce / sqrt(Cd) [-]
C specific humidity difference [kg/kg]
_RL delq (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL deltap(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
#ifdef EXF_CALC_ATMRHO
C local atmospheric density [kg/m^3]
_RL atmrho_loc(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
#endif
C
_RL ssq (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
_RL ren, rhn ! neutral, zref (=10m) values of re, rh
_RL usn, usm ! neutral, zref (=10m) wind-speed (+limited)
_RL stable ! = 1 if stable ; = 0 if unstable
C stability parameter at zwd [-] (=z/Monin-Obuklov length)
_RL huol
_RL htol ! stability parameter at zth [-]
_RL hqol
_RL x ! stability function [-]
_RL xsq ! = x^2 [-]
_RL psimh ! momentum stability function
_RL psixh ! latent & sensib. stability function
_RL zwln ! = log(zwd/zref)
_RL ztln ! = log(zth/zref)
_RL tau ! surface stress coef = rhoA * Ws * sqrt(Cd)
_RL tmpbulk
C additional variables that are copied from bulkf_formula_lay:
C upward LW at surface (W m-2)
_RL flwup
C net (downward) LW at surface (W m-2)
_RL flwNet_dwn
C gradients of latent/sensible net upward heat flux
C w/ respect to temperature
_RL dflhdT
_RL dfshdT
_RL dflwupdT
C emissivities, called emittance in exf
_RL emiss
C Tsf :: surface temperature [K]
C Ts2 :: surface temperature square [K^2]
_RL Tsf
_RL Ts2
C latent heat of evaporation or sublimation [J/kg]
_RL lath
_RL qsat_fac
_RL qsat_exp
#ifdef ALLOW_DBUG_THSICE
LOGICAL dBugFlag
INTEGER stdUnit
#endif
C == external functions ==
c _RL exf_BulkqSat
c external exf_BulkqSat
c _RL exf_BulkCdn
c external exf_BulkCdn
c _RL exf_BulkRhn
c external exf_BulkRhn
C == end of interface ==
C- Define grid-point location where to print debugging values
#include "THSICE_DEBUG.h"
#ifdef ALLOW_DBUG_THSICE
dBugFlag = debugLevel.GE.debLevC
stdUnit = standardMessageUnit
#endif
C-- Set surface parameters :
zwln = LOG(hu/zref)
ztln = LOG(ht/zref)
czol = hu*karman*gravity_mks
ren = cDalton
C more abbreviations
lath = flamb+flami
qsat_fac = cvapor_fac_ice
qsat_exp = cvapor_exp_ice
C initialisation of local arrays
DO j = 1-OLy,sNy+OLy
DO i = 1-OLx,sNx+OLx
tstar(i,j) = 0. _d 0
qstar(i,j) = 0. _d 0
ustar(i,j) = 0. _d 0
rdn(i,j) = 0. _d 0
rd(i,j) = 0. _d 0
rh(i,j) = 0. _d 0
re(i,j) = 0. _d 0
delq(i,j) = 0. _d 0
deltap(i,j) = 0. _d 0
ssq(i,j) = 0. _d 0
ENDDO
ENDDO
C
DO j=jMin,jMax
DO i=iMin,iMax
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
#ifdef ALLOW_DBUG_THSICE
IF ( dBug(i,j,bi,bj) .AND. (icFlag(i,j).GT.0. _d 0) )
& WRITE(stdUnit,'(A,2I4,2I2,2F12.6)')
& 'ThSI_GET_EXF: i,j,atemp,lwd=',
& i,j,bi,bj, atemp(i,j,bi,bj),lwdown(i,j,bi,bj)
#endif
#ifdef ALLOW_AUTODIFF_TAMC
act1 = bi - myBxLo(myThid)
max1 = myBxHi(myThid) - myBxLo(myThid) + 1
act2 = bj - myByLo(myThid)
max2 = myByHi(myThid) - myByLo(myThid) + 1
act3 = myThid - 1
max3 = nTx*nTy
act4 = ikey_dynamics - 1
ikey_1 = i
& + sNx*(j-1)
& + sNx*sNy*(it2-1)
& + sNx*sNy*MaxTsf*act1
& + sNx*sNy*MaxTsf*max1*act2
& + sNx*sNy*MaxTsf*max1*max2*act3
& + sNx*sNy*MaxTsf*max1*max2*max3*act4
#endif
C-- Use atmospheric state to compute surface fluxes.
IF ( (icFlag(i,j).GT.0. _d 0) .AND.
& (atemp(i,j,bi,bj).NE.0. _d 0) ) THEN
IF ( hSnow1(i,j).GT.3. _d -1 ) THEN
emiss = snow_emissivity
ELSE
emiss = ice_emissivity
ENDIF
C copy a few variables to names used in bulkf_formula_lay
Tsf = tsfCel(i,j)+cen2kel
Ts2 = Tsf*Tsf
C wind speed
#ifdef ALLOW_AUTODIFF_TAMC
CADJ STORE sh(i,j,bi,bj) = comlev1_thsice_3, key = ikey_1
#endif
wsm = sh(i,j,bi,bj)
C-- air - surface difference of temperature & humidity
c tmpbulk= exf_BulkqSat(Tsf)
c ssq(i,j) = saltsat*tmpbulk/atmrho
tmpbulk = qsat_fac*EXP(-qsat_exp/Tsf)
#ifdef EXF_CALC_ATMRHO
atmrho_loc(i,j) = apressure(i,j,bi,bj) /
& (287.04 _d 0*atemp(i,j,bi,bj)
& *(1. _d 0 + humid_fac*aqh(i,j,bi,bj)))
ssq(i,j) = tmpbulk/atmrho_loc(i,j)
#else
ssq(i,j) = tmpbulk/atmrho
#endif
deltap(i,j) = atemp(i,j,bi,bj) + gamma_blk*ht - Tsf
delq(i,j) = aqh(i,j,bi,bj) - ssq(i,j)
C Do the part of the output variables that do not depend
C on the ice here to save a few re-computations
C This is not yet dEvdT, but just a cheap way to save a 2D-field
C for ssq and recomputing Ts2 lateron
dEvdT(i,j) = ssq(i,j)*qsat_exp/Ts2
flwup = emiss*stefanBoltzmann*Ts2*Ts2
dflwupdT = emiss*stefanBoltzmann*Ts2*Tsf * 4. _d 0
c flwNet_dwn = lwdown(i,j,bi,bj) - flwup
C- assume long-wave albedo = 1 - emissivity :
flwNet_dwn = emiss*lwdown(i,j,bi,bj) - flwup
C-- This is not yet the total derivative with respect to surface temperature
dFlxdT(i,j) = -dflwupdT
C-- This is not yet the Net downward radiation excluding shortwave
flxExcSw(i,j) = flwNet_dwn
ENDIF
ENDDO
ENDDO
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
IF ( useStabilityFct_overIce ) THEN
DO j=jMin,jMax
DO i=iMin,iMax
#ifdef ALLOW_AUTODIFF_TAMC
act1 = bi - myBxLo(myThid)
max1 = myBxHi(myThid) - myBxLo(myThid) + 1
act2 = bj - myByLo(myThid)
max2 = myByHi(myThid) - myByLo(myThid) + 1
act3 = myThid - 1
max3 = nTx*nTy
act4 = ikey_dynamics - 1
ikey_1 = i
& + sNx*(j-1)
& + sNx*sNy*(it2-1)
& + sNx*sNy*MaxTsf*act1
& + sNx*sNy*MaxTsf*max1*act2
& + sNx*sNy*MaxTsf*max1*max2*act3
& + sNx*sNy*MaxTsf*max1*max2*max3*act4
C--
CADJ STORE sh(i,j,bi,bj) = comlev1_thsice_3, key = ikey_1
#endif
IF ( (icFlag(i,j).GT.0. _d 0) .AND.
& (atemp(i,j,bi,bj).NE.0. _d 0) ) THEN
C-- Compute the turbulent surface fluxes (function of stability).
C Initial guess: z/l=0.0; hu=ht=hq=z
C Iterations: converge on z/l and hence the fluxes.
t0 = atemp(i,j,bi,bj)*
& (exf_one + humid_fac*aqh(i,j,bi,bj))
stable = exf_half + SIGN(exf_half, deltap(i,j))
c tmpbulk = exf_BulkCdn(sh(i,j,bi,bj))
wsm = sh(i,j,bi,bj)
tmpbulk = cdrag_1/wsm + cdrag_2 + cdrag_3*wsm
IF (tmpbulk.NE.0.) THEN
rdn(i,j) = SQRT(tmpbulk)
ELSE
rdn(i,j) = 0. _d 0
ENDIF
C-- initial guess for exchange other coefficients:
c rhn = exf_BulkRhn(stable)
rhn = (exf_one-stable)*cstanton_1 + stable*cstanton_2
C-- calculate turbulent scales
ustar(i,j) = rdn(i,j)*wsm
tstar(i,j) = rhn*deltap(i,j)
qstar(i,j) = ren*delq(i,j)
ENDIF
ENDDO
ENDDO
C start iteration
DO iter = 1,niter_bulk
DO j=jMin,jMax
DO i=iMin,iMax
IF ( (icFlag(i,j).GT.0. _d 0) .AND.
& (atemp(i,j,bi,bj).NE.0. _d 0) ) THEN
#ifdef ALLOW_AUTODIFF_TAMC
ikey_2 = iter
& + niter_bulk*(i-1)
& + niter_bulk*sNx*(j-1)
& + niter_bulk*sNx*sNy*(it2-1)
& + niter_bulk*sNx*sNy*MaxTsf*act1
& + niter_bulk*sNx*sNy*MaxTsf*max1*act2
& + niter_bulk*sNx*sNy*MaxTsf*max1*max2*act3
& + niter_bulk*sNx*sNy*MaxTsf*max1*max2*max3*act4
CADJ STORE rdn(i,j) = comlev1_thsice_5, key = ikey_2
CADJ STORE ustar(i,j) = comlev1_thsice_5, key = ikey_2
CADJ STORE qstar(i,j) = comlev1_thsice_5, key = ikey_2
CADJ STORE tstar(i,j) = comlev1_thsice_5, key = ikey_2
CADJ STORE sh(i,j,bi,bj) = comlev1_thsice_5, key = ikey_2
#endif
t0 = atemp(i,j,bi,bj)*
& (exf_one + humid_fac*aqh(i,j,bi,bj))
huol = (tstar(i,j)/t0 +
& qstar(i,j)/(exf_one/humid_fac+aqh(i,j,bi,bj))
& )*czol/(ustar(i,j)*ustar(i,j))
#ifdef ALLOW_BULK_LARGEYEAGER04
C- Large&Yeager_2004 code:
huol = MIN( MAX(-10. _d 0,huol), 10. _d 0 )
#else
C- Large&Pond_1981 code (zolmin default = -100):
huol = MAX(huol,zolmin)
#endif /* ALLOW_BULK_LARGEYEAGER04 */
htol = huol*ht/hu
hqol = huol*hq/hu
stable = exf_half + SIGN(exf_half, huol)
C Evaluate all stability functions assuming hq = ht.
#ifdef ALLOW_BULK_LARGEYEAGER04
C- Large&Yeager_2004 code:
xsq = SQRT( ABS(exf_one - huol*16. _d 0) )
#else
C- Large&Pond_1981 code:
xsq = MAX(SQRT(ABS(exf_one - huol*16. _d 0)),exf_one)
#endif /* ALLOW_BULK_LARGEYEAGER04 */
x = SQRT(xsq)
psimh = -psim_fac*huol*stable
& + (exf_one-stable)
& *( LOG( (exf_one + exf_two*x + xsq)
& *(exf_one+xsq)*0.125 _d 0 )
& -exf_two*ATAN(x) + exf_half*pi )
#ifdef ALLOW_BULK_LARGEYEAGER04
C- Large&Yeager_2004 code:
xsq = SQRT( ABS(exf_one - htol*16. _d 0) )
#else
C- Large&Pond_1981 code:
xsq = MAX(SQRT(ABS(exf_one - htol*16. _d 0)),exf_one)
#endif /* ALLOW_BULK_LARGEYEAGER04 */
psixh = -psim_fac*htol*stable
& + (exf_one-stable)
& *exf_two*LOG( exf_half*(exf_one+xsq) )
C Shift wind speed using old coefficient
#ifdef ALLOW_BULK_LARGEYEAGER04
C-- Large&Yeager04:
usn = wspeed(i,j,bi,bj)
& /( exf_one + rdn(i,j)*(zwln-psimh)/karman )
#else
C-- Large&Pond1981:
usn = sh(i,j,bi,bj)/(exf_one - rdn(i,j)/karman*psimh)
#endif /* ALLOW_BULK_LARGEYEAGER04 */
usm = MAX(usn, umin)
C- Update the 10m, neutral stability transfer coefficients
c tmpbulk= exf_BulkCdn(usm)
tmpbulk= cdrag_1/usm + cdrag_2 + cdrag_3*usm
rdn(i,j) = SQRT(tmpbulk)
c rhn = exf_BulkRhn(stable)
rhn = (exf_one-stable)*cstanton_1 + stable*cstanton_2
C Shift all coefficients to the measurement height and stability.
#ifdef ALLOW_BULK_LARGEYEAGER04
rd(i,j)= rdn(i,j)/( exf_one + rdn(i,j)*(zwln-psimh)/karman )
#else
rd(i,j)= rdn(i,j)/( exf_one - rdn(i,j)/karman*psimh )
#endif /* ALLOW_BULK_LARGEYEAGER04 */
rh(i,j)= rhn/( exf_one + rhn*(ztln-psixh)/karman )
re(i,j)= ren/( exf_one + ren*(ztln-psixh)/karman )
C Update ustar, tstar, qstar using updated, shifted coefficients.
ustar(i,j) = rd(i,j)*sh(i,j,bi,bj)
qstar(i,j) = re(i,j)*delq(i,j)
tstar(i,j) = rh(i,j)*deltap(i,j)
ENDIF
C end i/j-loops
ENDDO
ENDDO
C end iteration loop
ENDDO
DO j=jMin,jMax
DO i=iMin,iMax
IF ( (icFlag(i,j).GT.0. _d 0) .AND.
& (atemp(i,j,bi,bj).NE.0. _d 0) ) THEN
#ifdef EXF_CALC_ATMRHO
tau = atmrho_loc(i,j)*rd(i,j)*wspeed(i,j,bi,bj)
#else
tau = atmrho*rd(i,j)*wspeed(i,j,bi,bj)
#endif
evapLoc(i,j) = -tau*qstar(i,j)
hlLocal = -lath*evapLoc(i,j)
hsLocal = atmcp*tau*tstar(i,j)
c ustress = tau*rd(i,j)*UwindSpeed
c vstress = tau*rd(i,j)*VwindSpeed
C--- surf.Temp derivative of turbulent Fluxes
C complete computation of dEvdT
dEvdT(i,j) = (tau*re(i,j))*dEvdT(i,j)
dflhdT = -lath*dEvdT(i,j)
dfshdT = -atmcp*tau*rh(i,j)
C-- Update total derivative with respect to surface temperature
dFlxdT(i,j) = dFlxdT(i,j) + dfshdT + dflhdT
C-- Update net downward radiation excluding shortwave
flxExcSw(i,j) = flxExcSw(i,j) + hsLocal + hlLocal
ENDIF
ENDDO
ENDDO
ELSE
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
C-- Compute the turbulent surface fluxes using fixed transfert Coeffs
C with no stability dependence ( useStabilityFct_overIce = false )
DO j=jMin,jMax
DO i=iMin,iMax
IF ( (icFlag(i,j).GT.0. _d 0) .AND.
& (atemp(i,j,bi,bj).NE.0. _d 0) ) THEN
wsm = sh(i,j,bi,bj)
#ifdef EXF_CALC_ATMRHO
tau = atmrho_loc(i,j)*exf_iceCe*wsm
#else
tau = atmrho*exf_iceCe*wsm
#endif
evapLoc(i,j) = -tau*delq(i,j)
hlLocal = -lath*evapLoc(i,j)
#ifdef EXF_CALC_ATMRHO
hsLocal = atmcp*atmrho_loc(i,j)
& *exf_iceCh*wsm*deltap(i,j)
#else
hsLocal = atmcp*atmrho*exf_iceCh*wsm*deltap(i,j)
#endif
#ifdef ALLOW_DBUG_THSICE
IF ( dBug(i,j,bi,bj) ) WRITE(stdUnit,'(A,4F12.6)')
& 'ThSI_GET_EXF: wsm,hl,hs,Lw=',
& wsm,hlLocal,hsLocal,flxExcSw(i,j)
#endif
C--- surf.Temp derivative of turbulent Fluxes
C complete computation of dEvdT
dEvdT(i,j) = tau*dEvdT(i,j)
dflhdT = -lath*dEvdT(i,j)
#ifdef EXF_CALC_ATMRHO
dfshdT = -atmcp*atmrho_loc(i,j)*exf_iceCh*wsm
#else
dfshdT = -atmcp*atmrho*exf_iceCh*wsm
#endif
C-- Update total derivative with respect to surface temperature
dFlxdT(i,j) = dFlxdT(i,j) + dfshdT + dflhdT
C-- Update net downward radiation excluding shortwave
flxExcSw(i,j) = flxExcSw(i,j) + hsLocal + hlLocal
#ifdef ALLOW_DBUG_THSICE
IF ( dBug(i,j,bi,bj) ) WRITE(stdUnit,'(A,4F12.6)')
& 'ThSI_GET_EXF: flx,dFlxdT,evap,dEvdT',
& flxExcSw(i,j), dFlxdT(i,j), evapLoc(i,j),dEvdT(i,j)
#endif
ENDIF
ENDDO
ENDDO
C endif useStabilityFct_overIce
ENDIF
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
DO j=jMin,jMax
DO i=iMin,iMax
IF ( (icFlag(i,j).GT.0. _d 0) .AND.
& (atemp(i,j,bi,bj).LE.0. _d 0) ) THEN
C-- in case atemp is zero:
flxExcSw(i,j) = 0. _d 0
dFlxdT (i,j) = 0. _d 0
evapLoc (i,j) = 0. _d 0
dEvdT (i,j) = 0. _d 0
ENDIF
ENDDO
ENDDO
#else /* ALLOW_DOWNWARD_RADIATION */
STOP 'ABNORMAL END: S/R THSICE_GET_EXF: DOWNWARD_RADIATION undef'
#endif /* ALLOW_DOWNWARD_RADIATION */
#else /* ALLOW_ATM_TEMP */
STOP 'ABNORMAL END: S/R THSICE_GET_EXF: ATM_TEMP undef'
#endif /* ALLOW_ATM_TEMP */
#ifdef EXF_READ_EVAP
STOP 'ABNORMAL END: S/R THSICE_GET_EXF: EXF_READ_EVAP defined'
#endif /* EXF_READ_EVAP */
#endif /* ALLOW_EXF */
RETURN
END