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C $Header: /u/gcmpack/MITgcm/pkg/seaice/seaice_budget_ocean.F,v 1.3 2007/04/16 22:43:01 mlosch Exp $ |
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C $Name: $ |
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|
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#include "SEAICE_OPTIONS.h" |
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|
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CStartOfInterface |
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SUBROUTINE SEAICE_BUDGET_OCEAN( |
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I UG, |
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U TSURF, |
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O netHeatFlux, SWHeatFlux, |
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I bi, bj, myThid ) |
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C /================================================================\ |
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C | SUBROUTINE seaice_budget_ocean | |
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C | o Calculate surface heat fluxes over open ocean | |
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C | see Hibler, MWR, 108, 1943-1973, 1980 | |
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C | If SEAICE_EXTERNAL_FLUXES is defined this routine simply | |
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C | simply copies the global fields to the seaice-local fields. | |
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C |================================================================| |
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C \================================================================/ |
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IMPLICIT NONE |
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|
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C === Global variables === |
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#include "SIZE.h" |
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#include "EEPARAMS.h" |
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#include "FFIELDS.h" |
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#include "SEAICE_PARAMS.h" |
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#include "SEAICE_FFIELDS.h" |
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#ifdef SEAICE_VARIABLE_FREEZING_POINT |
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#include "DYNVARS.h" |
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#endif /* SEAICE_VARIABLE_FREEZING_POINT */ |
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|
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C === Routine arguments === |
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C INPUT: |
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C UG :: thermal wind of atmosphere |
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C TSURF :: surface temperature of ocean in Kelvin |
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C bi,bj :: loop indices |
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C myThid :: Thread no. that called this routine. |
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C OUTPUT: |
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C netHeatFlux :: net surface heat flux over open water or under ice |
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C SWHeatFlux :: short wave heat flux over open water or under ice |
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_RL UG (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL TSURF (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL netHeatFlux(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL SWHeatFlux (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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INTEGER bi, bj, myThid |
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CEndOfInterface |
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|
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C === Local variables === |
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C i,j - Loop counters |
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INTEGER i, j |
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#ifndef SEAICE_EXTERNAL_FLUXES |
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INTEGER ITER |
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_RL QS1, TB, D1, D1W, D3, TMELT |
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C effective conductivity of combined ice and snow |
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_RL effConduct |
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C specific humidity at ice surface |
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_RL qhIce |
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C powers of temperature |
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_RL t1, t2, t3, t4 |
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|
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C local copies of global variables |
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_RL tsurfLoc (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL atempLoc (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL lwdownLoc (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL ALB (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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C coefficients of Hibler (1980), appendix B |
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_RL A1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL A2 (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL A3 (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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C auxiliary variable |
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_RL B (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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|
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C NOW DEFINE ASSORTED CONSTANTS |
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C SATURATION VAPOR PRESSURE CONSTANT |
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QS1=0.622 _d +00/1013.0 _d +00 |
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C FREEZING TEMPERATURE OF SEAWATER |
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TB=271.2 _d +00 |
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C SENSIBLE HEAT CONSTANT |
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D1=SEAICE_sensHeat |
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C WATER LATENT HEAT CONSTANT |
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D1W=SEAICE_latentWater |
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C STEFAN BOLTZMAN CONSTANT TIMES 0.97 EMISSIVITY |
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D3=SEAICE_emissivity |
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C MELTING TEMPERATURE OF ICE |
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TMELT=273.16 _d +00 |
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DO J=1,sNy |
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DO I=1,sNx |
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netHeatFlux(I,J) = 0. _d 0 |
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SWHeatFlux (I,J) = 0. _d 0 |
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C |
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tsurfLoc (I,J) = MIN(273.16 _d 0+MAX_TICE,TSURF(I,J,bi,bj)) |
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C Is this necessary? |
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#ifdef ALLOW_ATM_TEMP |
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atempLoc (I,J) = MAX(273.16 _d 0+MIN_ATEMP,ATEMP(I,J,bi,bj)) |
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#else /* ALLOW_ATM_TEMP */ |
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STOP 'ABNORMAL END: S/R SEAICE_BUDGET_OCE: ATM_TEMP undef' |
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#endif /* ALLOW_ATM_TEMP */ |
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#ifdef ALLOW_DOWNWARD_RADIATION |
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lwdownLoc(I,J) = MAX(MIN_LWDOWN,LWDOWN(I,J,bi,bj)) |
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#else |
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STOP |
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& 'ABNORMAL END: S/R SEAICE_BUDGET_OCE: DOWNWARD_RADIATION undef' |
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#endif |
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ENDDO |
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ENDDO |
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#endif /* SEAICE_EXTERNAL_FLUXES */ |
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C NOW DETERMINE OPEN WATER HEAT BUD. ASSUMING TSURF=WATER TEMP. |
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C WATER ALBEDO IS ASSUMED TO BE THE CONSTANT SEAICE_waterAlbedo |
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DO J=1,sNy |
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DO I=1,sNx |
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#ifdef SEAICE_EXTERNAL_FLUXES |
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netHeatFlux(I,J) = Qnet(I,J,bi,bj) |
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SWHeatFlux (I,J) = Qsw(I,J,bi,bj) |
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#else /* SEAICE_EXTERNAL_FLUXES undefined */ |
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ALB(I,J)=SEAICE_waterAlbedo |
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#if defined(ALLOW_DOWNWARD_RADIATION) && defined(ALLOW_ATM_TEMP) |
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A1(I,J)=(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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& +lwdownLoc(I,J)*0.97 _d 0 |
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& +D1*UG(I,J)*atempLoc(I,J)+D1W*UG(I,J)*AQH(I,J,bi,bj) |
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B(I,J)=QS1*6.11 _d +00*EXP(17.2694 _d +00 |
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& *(tsurfLoc(I,J)-TMELT) |
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& /(tsurfLoc(I,J)-TMELT+237.3 _d +00)) |
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A2(I,J)=-D1*UG(I,J)*tsurfLoc(I,J)-D1W*UG(I,J)*B(I,J) |
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& -D3*(tsurfLoc(I,J)**4) |
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netHeatFlux(I,J)=-A1(I,J)-A2(I,J) |
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SWHeatFlux (I,J)=-(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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#else |
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STOP |
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& 'ABNORMAL END: S/R SEAICE_BUDGET_OCE: DOWNWARD_RADIATION undef' |
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#endif |
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#endif /* SEAICE_EXTERNAL_FLUXES */ |
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ENDDO |
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ENDDO |
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|
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RETURN |
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END |