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C $Header: /u/gcmpack/MITgcm/pkg/seaice/budget.F,v 1.11 2003/10/09 04:19:20 edhill Exp $ |
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C $Name: $ |
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#include "SEAICE_OPTIONS.h" |
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|
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CStartOfInterface |
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SUBROUTINE BUDGET(UG, TICE, HICE1, FICE1, KOPEN, bi, bj) |
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C /==========================================================\ |
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C | SUBROUTINE budget | |
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C | o Calculate ice growth rate | |
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C | see Hibler, MWR, 108, 1943-1973, 1980 | |
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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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|
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C Subset of variables from SEAICE.h |
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_RL HEFF (1-OLx:sNx+OLx,1-OLy:sNy+OLy,3,nSx,nSy) |
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_RL HSNOW (1-OLx:sNx+OLx,1-OLy:sNy+OLy, nSx,nSy) |
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_RL QNETO (1-OLx:sNx+OLx,1-OLy:sNy+OLy, nSx,nSy) |
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_RL QNETI (1-OLx:sNx+OLx,1-OLy:sNy+OLy, nSx,nSy) |
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_RL QSWO (1-OLx:sNx+OLx,1-OLy:sNy+OLy, nSx,nSy) |
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_RL QSWI (1-OLx:sNx+OLx,1-OLy:sNy+OLy, nSx,nSy) |
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COMMON/TRANS/HEFF,HSNOW |
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COMMON/QFLUX/QNETO,QNETI,QSWO,QSWI |
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|
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C === Routine arguments === |
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_RL UG (1-OLx:sNx+OLx, 1-OLy:sNy+OLy) |
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_RL TICE (1-OLx:sNx+OLx, 1-OLy:sNy+OLy, nSx,nSy) |
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_RL HICE1 (1-OLx:sNx+OLx, 1-OLy:sNy+OLy) |
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_RL FICE1 (1-OLx:sNx+OLx, 1-OLy:sNy+OLy, nSx,nSy) |
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INTEGER KOPEN |
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INTEGER bi, bj |
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CEndOfInterface |
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|
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#ifdef ALLOW_SEAICE |
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|
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C === Local variables === |
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C i,j,k,bi,bj - Loop counters |
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|
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INTEGER i, j |
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INTEGER ITER |
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_RL QS1, C1, C2, C3, C4, C5, TB, D1, D1W, D1I, D3 |
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_RL TMELT, TMELTP, XKI, XKS, HCUT, ASNOW, XIO |
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|
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_RL HICE (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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_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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_RL B (1-OLx:sNx+OLx, 1-OLy:sNy+OLy) |
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|
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_RL mymin_R8, mymax_R8 |
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external mymin_R8, mymax_R8 |
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|
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C IF KOPEN LT 0, THEN DO OPEN WATER BUDGET |
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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 MAYKUTS CONSTANTS FOR SAT. VAP. PRESSURE TEMP. POLYNOMIAL |
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C1=2.7798202 _d -06 |
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C2=-2.6913393 _d -03 |
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C3=0.97920849 _d +00 |
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C4=-158.63779 _d +00 |
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C5=9653.1925 _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 ICE LATENT HEAT CONSTANT |
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D1I=SEAICE_latentIce |
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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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TMELTP=273.159 _d +00 |
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C ICE CONDUCTIVITY |
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XKI=SEAICE_iceConduct |
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C SNOW CONDUCTIVITY |
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XKS=SEAICE_snowConduct |
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C CUTOFF SNOW THICKNESS |
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HCUT=SEAICE_snowThick |
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C PENETRATION SHORTWAVE RADIATION FACTOR |
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XIO=SEAICE_shortwave |
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|
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DO J=1,sNy |
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DO I=1,sNx |
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TICE(I,J,bi,bj)=MYMIN_R8(273.16 _d 0+MAX_TICE,TICE(I,J,bi,bj)) |
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ATEMP(I,J,bi,bj)=MYMAX_R8(273.16 _d 0+MIN_ATEMP,ATEMP(I,J,bi,bj)) |
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LWDOWN(I,J,bi,bj)=MYMAX_R8(MIN_LWDOWN,LWDOWN(I,J,bi,bj)) |
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ENDDO |
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ENDDO |
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|
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C NOW DECIDE IF OPEN WATER OR ICE |
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IF(KOPEN.LE.0) THEN |
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|
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C NOW DETERMINE OPEN WATER HEAT BUD. ASSUMING TICE=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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FICE1(I,J,bi,bj)=QNET(I,J,bi,bj)+Qsw(I,J,bi,bj) |
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QSWO(I,J,bi,bj)=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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A1(I,J)=(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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& +LWDOWN(I,J,bi,bj)*0.97 _d 0 |
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& +D1*UG(I,J)*ATEMP(I,J,bi,bj)+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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& *(TICE(I,J,bi,bj)-TMELT) |
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& /(TICE(I,J,bi,bj)-TMELT+237.3 _d +00)) |
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A2(I,J)=-D1*UG(I,J)*TICE(I,J,bi,bj)-D1W*UG(I,J)*B(I,J) |
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& -D3*(TICE(I,J,bi,bj)**4) |
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FICE1(I,J,bi,bj)=-A1(I,J)-A2(I,J) |
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QSWO(I,J,bi,bj)=-(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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#endif /* SEAICE_EXTERNAL_FLUXES */ |
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QNETO(I,J,bi,bj)=FICE1(I,J,bi,bj)-QSWO(I,J,bi,bj) |
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ENDDO |
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ENDDO |
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|
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ELSE |
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|
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C COME HERE IF ICE COVER |
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C FIRST PUT MINIMUM ON ICE THICKNESS |
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DO J=1,sNy |
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DO I=1,sNx |
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HICE(I,J)=MYMAX_R8(HICE1(I,J),0.05 _d +00) |
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HICE(I,J)=MYMIN_R8(HICE(I,J),9.0 _d +00) |
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ENDDO |
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ENDDO |
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C NOW DECIDE ON ALBEDO |
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DO J=1,sNy |
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DO I=1,sNx |
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ALB(I,J)=SEAICE_dryIceAlb |
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IF(TICE(I,J,bi,bj).GT.TMELTP) ALB(I,J)=SEAICE_wetIceAlb |
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ASNOW=SEAICE_drySnowAlb |
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IF(TICE(I,J,bi,bj).GT.TMELTP) ASNOW=SEAICE_wetSnowAlb |
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IF(HSNOW(I,J,bi,bj).GT.HCUT) THEN |
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ALB(I,J)=ASNOW |
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ELSE |
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ALB(I,J)=ALB(I,J)+(HSNOW(I,J,bi,bj)/HCUT)*(ASNOW-ALB(I,J)) |
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IF(ALB(I,J).GT.ASNOW) ALB(I,J)=ASNOW |
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END IF |
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ENDDO |
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ENDDO |
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C NOW DETERMINE FIXED FORCING TERM IN HEAT BUDGET |
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DO J=1,sNy |
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DO I=1,sNx |
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IF(HSNOW(I,J,bi,bj).GT.0.0) THEN |
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C NO SW PENETRATION WITH SNOW |
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A1(I,J)=(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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& +LWDOWN(I,J,bi,bj)*0.97 _d 0 |
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& +D1*UG(I,J)*ATEMP(I,J,bi,bj)+D1I*UG(I,J)*AQH(I,J,bi,bj) |
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ELSE |
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C SW PENETRATION UNDER ICE |
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A1(I,J)=(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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& *(ONE-XIO*EXP(-1.5 _d 0*HICE(I,J))) |
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& +LWDOWN(I,J,bi,bj)*0.97 _d 0 |
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& +D1*UG(I,J)*ATEMP(I,J,bi,bj)+D1I*UG(I,J)*AQH(I,J,bi,bj) |
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ENDIF |
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ENDDO |
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ENDDO |
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C NOW COMPUTE OTHER TERMS IN HEAT BUDGET |
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C COME HERE AT START OF ITERATION |
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|
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crg check wether a2 is needed in the list of variables |
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cdm Ralf, the line below causes following error message |
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cdm INTERNAL ERROR: cannot find var clone to ada2 |
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cdm c$taf loop = iteration TICE,A2 |
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cdm iterative solver for ice growth rate |
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cdm inputs: TICE ice temperature |
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cdm UG forcing |
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cdm HSNOW snow thickness |
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cdm HICE ice thickness |
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cdm outputs: A2 is needed for FICE1, which is ice growth rate |
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cdm TICE |
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DO ITER=1,IMAX_TICE |
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|
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DO J=1,sNy |
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DO I=1,sNx |
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B(I,J)=QS1*(C1*TICE(I,J,bi,bj)**4+C2*TICE(I,J,bi,bj)**3 |
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& +C3*TICE(I,J,bi,bj)**2+C4*TICE(I,J,bi,bj)+C5) |
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A2(I,J)=-D1*UG(I,J)*TICE(I,J,bi,bj)-D1I*UG(I,J)*B(I,J) |
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& -D3*(TICE(I,J,bi,bj)**4) |
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B(I,J)=XKS/(HSNOW(I,J,bi,bj)/HICE(I,J)+XKS/XKI)/HICE(I,J) |
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A3(I,J)=4.0 _d +00*D3*(TICE(I,J,bi,bj)**3)+B(I,J)+D1*UG(I,J) |
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B(I,J)=B(I,J)*(TB-TICE(I,J,bi,bj)) |
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cdm |
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cdm if(TICE(I,J,bi,bj).le.206.) |
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cdm & print '(A,3i4,f12.2)','### ITER,I,J,TICE', |
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cdm & ITER,I,J,TICE(I,J,bi,bj) |
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cdm |
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ENDDO |
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ENDDO |
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C NOW DECIDE IF IT IS TIME TO ESTIMATE GROWTH RATES |
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C NOW DETERMINE NEW ICE TEMPERATURE |
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DO J=1,sNy |
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DO I=1,sNx |
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TICE(I,J,bi,bj)=TICE(I,J,bi,bj) |
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& +(A1(I,J)+A2(I,J)+B(I,J))/A3(I,J) |
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TICE(I,J,bi,bj)=MYMAX_R8(273.16 _d 0+MIN_TICE,TICE(I,J,bi,bj)) |
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ENDDO |
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ENDDO |
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C NOW SET ICE TEMP TO MIN OF TMELT/ITERATION RESULT |
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DO J=1,sNy |
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DO I=1,sNx |
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TICE(I,J,bi,bj)=MYMIN_R8(TICE(I,J,bi,bj),TMELT) |
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ENDDO |
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ENDDO |
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|
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C END OF ITERATION |
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ENDDO |
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|
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DO J=1,sNy |
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DO I=1,sNx |
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FICE1(I,J,bi,bj)=-A1(I,J)-A2(I,J) |
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IF(HSNOW(I,J,bi,bj).GT.0.0) THEN |
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C NO SW PENETRATION WITH SNOW |
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QSWI(I,J,bi,bj)=ZERO |
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ELSE |
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C SW PENETRATION UNDER ICE |
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QSWI(I,J,bi,bj)=-(ONE-ALB(I,J))*SWDOWN(I,J,bi,bj) |
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& *XIO*EXP(-1.5 _d 0*HICE(I,J)) |
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ENDIF |
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ENDDO |
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ENDDO |
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|
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END IF |
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|
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#endif /* ALLOW_SEAICE */ |
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|
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RETURN |
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END |