| 1 |
C $Header: /u/gcmpack/MITgcm/pkg/aim_v23/phy_suflux_sice.F,v 1.4 2004/06/24 23:43:11 jmc Exp $ |
| 2 |
C $Name: $ |
| 3 |
|
| 4 |
#include "AIM_OPTIONS.h" |
| 5 |
|
| 6 |
CBOP |
| 7 |
C !ROUTINE: SUFLUX_SICE |
| 8 |
C !INTERFACE: |
| 9 |
SUBROUTINE SUFLUX_SICE( |
| 10 |
I PSA, FMASK, EMISloc, |
| 11 |
I Tsurf, dTskin, SSR, SLRD, |
| 12 |
I T1, T0, Q0, DENVV, |
| 13 |
O SHF, EVAP, SLRU, |
| 14 |
O Shf0, dShf, Evp0, dEvp, Slr0, dSlr, sFlx, |
| 15 |
O TSFC, TSKIN, |
| 16 |
I bi,bj,myThid) |
| 17 |
|
| 18 |
C !DESCRIPTION: \bv |
| 19 |
C *==========================================================* |
| 20 |
C | S/R SUFLUX_SICE |
| 21 |
C | o compute surface flux over sea-ice |
| 22 |
C *==========================================================* |
| 23 |
C | o contains part of original S/R SUFLUX (Speedy code) |
| 24 |
C *==========================================================* |
| 25 |
C \ev |
| 26 |
|
| 27 |
C !USES: |
| 28 |
IMPLICIT NONE |
| 29 |
|
| 30 |
C Resolution parameters |
| 31 |
|
| 32 |
C-- size for MITgcm & Physics package : |
| 33 |
#include "AIM_SIZE.h" |
| 34 |
#include "EEPARAMS.h" |
| 35 |
|
| 36 |
C-- Physics package |
| 37 |
#include "AIM_PARAMS.h" |
| 38 |
|
| 39 |
C Physical constants + functions of sigma and latitude |
| 40 |
#include "com_physcon.h" |
| 41 |
|
| 42 |
C Surface flux constants |
| 43 |
#include "com_sflcon.h" |
| 44 |
|
| 45 |
C !INPUT/OUTPUT PARAMETERS: |
| 46 |
C == Routine Arguments == |
| 47 |
C-- Input: |
| 48 |
C PSA :: norm. surface pressure [p/p0] (2-dim) |
| 49 |
C FMASK :: fractional land-sea mask (2-dim) |
| 50 |
C EMISloc:: longwave surface emissivity |
| 51 |
C Tsurf :: surface temperature (2-dim) |
| 52 |
C dTskin :: temp. correction for daily-cycle heating [K] |
| 53 |
C SSR :: sfc sw radiation (net flux) (2-dim) |
| 54 |
C SLRD :: sfc lw radiation (downward flux)(2-dim) |
| 55 |
C T1 :: near-surface air temperature (from Pot.temp) |
| 56 |
C T0 :: near-surface air temperature (2-dim) |
| 57 |
C Q0 :: near-surface sp. humidity [g/kg](2-dim) |
| 58 |
C DENVV :: surface flux (sens,lat.) coeff. (=Rho*|V|) [kg/m2/s] |
| 59 |
C-- Output: |
| 60 |
C SHF :: sensible heat flux (2-dim) |
| 61 |
C EVAP :: evaporation [g/(m^2 s)] (2-dim) |
| 62 |
C SLRU :: sfc lw radiation (upward flux) (2-dim) |
| 63 |
C Shf0 :: sensible heat flux over freezing surf. |
| 64 |
C dShf :: sensible heat flux derivative relative to surf. temp |
| 65 |
C Evp0 :: evaporation computed over freezing surface (Ts=0.oC) |
| 66 |
C dEvp :: evaporation derivative relative to surf. temp |
| 67 |
C Slr0 :: upward long wave radiation over freezing surf. |
| 68 |
C dSlr :: upward long wave rad. derivative relative to surf. temp |
| 69 |
C sFlx :: net heat flux (+=down) except SW, function of surf. temp Ts: |
| 70 |
C 0: Flux(Ts=0.oC) ; 1: Flux(Ts^n) ; 2: d.Flux/d.Ts(Ts^n) |
| 71 |
C TSFC :: surface temperature (clim.) (2-dim) |
| 72 |
C TSKIN :: skin surface temperature (2-dim) |
| 73 |
C-- Input: |
| 74 |
C bi,bj :: tile index |
| 75 |
C myThid :: Thread number for this instance of the routine |
| 76 |
C-- |
| 77 |
_RL PSA(NGP), FMASK(NGP), EMISloc |
| 78 |
_RL Tsurf(NGP), dTskin(NGP) |
| 79 |
_RL SSR(NGP), SLRD(NGP) |
| 80 |
_RL T1(NGP), T0(NGP), Q0(NGP), DENVV(NGP) |
| 81 |
|
| 82 |
_RL SHF(NGP), EVAP(NGP), SLRU(NGP) |
| 83 |
_RL Shf0(NGP), dShf(NGP), Evp0(NGP), dEvp(NGP) |
| 84 |
_RL Slr0(NGP), dSlr(NGP), sFlx(NGP,0:2) |
| 85 |
_RL TSFC(NGP), TSKIN(NGP) |
| 86 |
|
| 87 |
INTEGER bi,bj,myThid |
| 88 |
CEOP |
| 89 |
|
| 90 |
#ifdef ALLOW_AIM |
| 91 |
|
| 92 |
C-- Local variables: |
| 93 |
C CDENVV :: surf. heat flux (sens.,lat.) coeff including stability effect |
| 94 |
C ALHevp :: Latent Heat of evaporation |
| 95 |
_RL CDENVV(NGP), RDTH, FSSICE |
| 96 |
_RL ALHevp, Fstb0, dTstb, dFstb |
| 97 |
_RL QSAT0(NGP,2) |
| 98 |
_RL QDUMMY(1), RDUMMY(1), TS2 |
| 99 |
INTEGER J |
| 100 |
|
| 101 |
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
| 102 |
|
| 103 |
ALHevp = ALHC |
| 104 |
C Evap of snow/ice: account for Latent Heat of freezing : |
| 105 |
IF ( aim_energPrecip ) ALHevp = ALHC + ALHF |
| 106 |
|
| 107 |
C 1.5 Define effective skin temperature to compensate for |
| 108 |
C non-linearity of heat/moisture fluxes during the daily cycle |
| 109 |
|
| 110 |
DO J=1,NGP |
| 111 |
c TSKIN(J) = Tsurf(J) + dTskin(J) |
| 112 |
c TSFC(J)=273.16 _d 0 + dTskin(J) |
| 113 |
TSKIN(J) = Tsurf(J) |
| 114 |
TSFC(J)=273.16 _d 0 |
| 115 |
ENDDO |
| 116 |
|
| 117 |
C-- 2. Computation of fluxes over land and sea |
| 118 |
|
| 119 |
C 2.1 Stability correction |
| 120 |
|
| 121 |
RDTH = FSTAB/DTHETA |
| 122 |
|
| 123 |
DO J=1,NGP |
| 124 |
FSSICE=1.+MIN(DTHETA,MAX(-DTHETA,TSKIN(J)-T1(J)))*RDTH |
| 125 |
CDENVV(J)=CHS*DENVV(J)*FSSICE |
| 126 |
ENDDO |
| 127 |
|
| 128 |
IF ( dTstab.GT.0. _d 0 ) THEN |
| 129 |
C- account for stability function derivative relative to Tsurf: |
| 130 |
C note: to avoid discontinuity in the derivative (because of min,max), compute |
| 131 |
C the derivative using the discrete form: F(Ts+dTstab)-F(Ts-dTstab)/2.dTstab |
| 132 |
DO J=1,NGP |
| 133 |
Fstb0 = 1.+MIN(DTHETA,MAX(-DTHETA,TSFC(J) -T1(J)))*RDTH |
| 134 |
Shf0(J) = CHS*DENVV(J)*Fstb0 |
| 135 |
dTstb = ( DTHETA+dTstab-ABS(TSKIN(J)-T1(J)) )/dTstab |
| 136 |
dFstb = RDTH*MIN(1. _d 0, MAX(0. _d 0, dTstb*0.5 _d 0)) |
| 137 |
dShf(J) = CHS*DENVV(J)*dFstb |
| 138 |
ENDDO |
| 139 |
C- deBug part: |
| 140 |
c J = 6 + (17-1)*sNx |
| 141 |
c IF ( bi.EQ.3 .AND. J.LE.NGP ) |
| 142 |
c & WRITE(6,1020)'SUFLUX_SICE: Stab=',Shf0(J),CDENVV(J),dShf(J) |
| 143 |
ENDIF |
| 144 |
|
| 145 |
C 2.2 Evaporation |
| 146 |
|
| 147 |
CALL SHTORH (2, NGP, TSKIN, PSA, 1. _d 0, QDUMMY, dEvp, |
| 148 |
& QSAT0(1,1), myThid) |
| 149 |
CALL SHTORH (0, NGP, TSFC, PSA, 1. _d 0, QDUMMY, RDUMMY, |
| 150 |
& QSAT0(1,2), myThid) |
| 151 |
|
| 152 |
IF ( dTstab.GT.0. _d 0 ) THEN |
| 153 |
C- account for stability function derivative relative to Tsurf: |
| 154 |
DO J=1,NGP |
| 155 |
EVAP(J) = CDENVV(J)*(QSAT0(J,1)-Q0(J)) |
| 156 |
Evp0(J) = Shf0(J)*(QSAT0(J,2)-Q0(J)) |
| 157 |
dEvp(J) = CDENVV(J)*dEvp(J) |
| 158 |
& + dShf(J)*(QSAT0(J,1)-Q0(J)) |
| 159 |
ENDDO |
| 160 |
ELSE |
| 161 |
DO J=1,NGP |
| 162 |
EVAP(J) = CDENVV(J)*(QSAT0(J,1)-Q0(J)) |
| 163 |
Evp0(J) = CDENVV(J)*(QSAT0(J,2)-Q0(J)) |
| 164 |
dEvp(J) = CDENVV(J)*dEvp(J) |
| 165 |
ENDDO |
| 166 |
ENDIF |
| 167 |
|
| 168 |
C 2.3 Sensible heat flux |
| 169 |
|
| 170 |
IF ( dTstab.GT.0. _d 0 ) THEN |
| 171 |
C- account for stability function derivative relative to Tsurf: |
| 172 |
DO J=1,NGP |
| 173 |
SHF(J) = CDENVV(J)*CP*(TSKIN(J)-T0(J)) |
| 174 |
Shf0(J) = Shf0(J)*CP*(TSFC(J) -T0(J)) |
| 175 |
dShf(J) = CDENVV(J)*CP |
| 176 |
& + dShf(J)*CP*(TSKIN(J)-T0(J)) |
| 177 |
dShf(J) = MAX( dShf(J), 0. _d 0 ) |
| 178 |
C-- do not allow negative derivative vs Ts of Sensible+Latent H.flux: |
| 179 |
C a) quiet unrealistic ; |
| 180 |
C b) garantee positive deriv. of total H.flux (needed for implicit solver) |
| 181 |
dEvp(J) = MAX( dEvp(J), -dShf(J)/ALHevp ) |
| 182 |
ENDDO |
| 183 |
ELSE |
| 184 |
DO J=1,NGP |
| 185 |
SHF(J) = CDENVV(J)*CP*(TSKIN(J)-T0(J)) |
| 186 |
Shf0(J) = CDENVV(J)*CP*(TSFC(J) -T0(J)) |
| 187 |
dShf(J) = CDENVV(J)*CP |
| 188 |
ENDDO |
| 189 |
ENDIF |
| 190 |
|
| 191 |
C 2.4 Emission of lw radiation from the surface |
| 192 |
|
| 193 |
DO J=1,NGP |
| 194 |
TS2 = TSFC(J)*TSFC(J) |
| 195 |
Slr0(J) = SBC*TS2*TS2 |
| 196 |
TS2 = TSKIN(J)*TSKIN(J) |
| 197 |
SLRU(J) = SBC*TS2*TS2 |
| 198 |
dSlr(J) = 4. _d 0 *SBC*TS2*TSKIN(J) |
| 199 |
ENDDO |
| 200 |
|
| 201 |
C-- Compute net surface heat flux and its derivative ./. surf. temp. |
| 202 |
DO J=1,NGP |
| 203 |
sFlx(J,0)= ( SLRD(J) - EMISloc*Slr0(J) ) |
| 204 |
& - ( Shf0(J) + ALHevp*Evp0(J) ) |
| 205 |
sFlx(J,1)= ( SLRD(J) - EMISloc*SLRU(J) ) |
| 206 |
& - ( SHF(J) + ALHevp*EVAP(J) ) |
| 207 |
sFlx(J,2)= -EMISloc*dSlr(J) |
| 208 |
& - ( dShf(J) + ALHevp*dEvp(J) ) |
| 209 |
ENDDO |
| 210 |
|
| 211 |
C- deBug part: ----------------- |
| 212 |
c1010 FORMAT(A,I3,2F10.3,F10.4) |
| 213 |
c1020 FORMAT(A,1P4E11.3) |
| 214 |
c J = 6 + (17-1)*sNx |
| 215 |
c IF ( bi.EQ.3 .AND. J.LE.NGP ) THEN |
| 216 |
c WRITE(6,1010) 'SUFLUX_SICE: 1,sFlx=', 1, |
| 217 |
c & sFlx(J,0),sFlx(J,1),sFlx(J,2) |
| 218 |
c WRITE(6,1010) 'SUFLUX_SICE: 0,Evap=', 0,Evp0(J),EVAP(J),dEvp(J) |
| 219 |
c WRITE(6,1010) 'SUFLUX_SICE: -,LWup=',-1,Slr0(J),SLRU(J),dSlr(J) |
| 220 |
c WRITE(6,1010) 'SUFLUX_SICE: -, SHF=',-1,Shf0(J),SHF(J), dShf(J) |
| 221 |
c WRITE(6,1010) 'SUFLUX_SICE: -, LAT=',-1, |
| 222 |
c & ALHevp*Evp0(J),ALHevp*EVAP(J),ALHevp*dEvp(J) |
| 223 |
c ENDIF |
| 224 |
|
| 225 |
C-- 3. Adjustment of skin temperature and fluxes over land |
| 226 |
C-- based on energy balance (to be implemented) |
| 227 |
C <= done separately for each surface type (land,ocean,sea-ice) |
| 228 |
|
| 229 |
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
| 230 |
#endif /* ALLOW_AIM */ |
| 231 |
|
| 232 |
RETURN |
| 233 |
END |
Parent Directory
| 
Revision Log
| 
Revision Graph