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C $Header: /u/gcmpack/MITgcm/pkg/aim_v23/phy_shtorh.F,v 1.3 2004/03/11 14:33:19 jmc Exp $ |
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C $Name: $ |
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|
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#include "AIM_OPTIONS.h" |
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|
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SUBROUTINE SHTORH (IMODE,NGP,TA,PS,SIG,QA,RH,QSAT,myThid) |
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C-- |
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C-- SUBROUTINE SHTORH (IMODE,NGP,TA,PS,SIG,QA,RH,QSAT) |
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C-- |
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C-- Purpose: compute saturation specific humidity and |
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C-- relative hum. from specific hum. (or viceversa) |
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C-- Input: IMODE : mode of operation |
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C-- NGP : no. of grid-points |
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C-- TA : abs. temperature |
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C-- PS : normalized pressure (= p/1000_hPa) [if SIG < 0] |
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C-- : normalized sfc. pres. (= ps/1000_hPa) [if SIG > 0] |
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C-- SIG : sigma level |
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C-- QA : specific humidity in g/kg [if IMODE = 1] |
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C-- RH : relative humidity [if IMODE < 0] |
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C-- Output: RH : relative humidity [if IMODE = 1] |
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C-- QA : specific humidity in g/kg [if IMODE < 0] |
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C-- QSAT : saturation spec. hum. in g/kg |
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C-- RH : d.Qsat/d.T in g/kg/K [if IMODE = 2] |
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C-- |
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|
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IMPLICIT NONE |
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|
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C-- Routine arguments: |
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INTEGER IMODE, NGP |
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INTEGER myThid |
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c _RL TA(NGP), PS(NGP), QA(NGP), RH(NGP), QSAT(NGP) |
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_RL TA(NGP), PS(NGP), QSAT(NGP), QA(*), RH(*) |
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|
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C- jmc: declare all routine arguments: |
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_RL SIG |
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|
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#ifdef ALLOW_AIM |
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|
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C-- Local variables: |
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INTEGER J |
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|
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C- jmc: declare all local variables: |
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_RL E0, C1, C2, T0, T1, T2, QS1, QS2 |
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_RL sigP, recT, tmpQ |
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C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
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|
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C--- 1. Compute Qsat (g/kg) from T (degK) and normalized pres. P (= p/1000_hPa) |
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C If SIG > 0, P = Ps * sigma, otherwise P = Ps(1) = const. |
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C |
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E0= 6.108 _d -3 |
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C1= 17.269 _d 0 |
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C2= 21.875 _d 0 |
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T0=273.16 _d 0 |
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T1= 35.86 _d 0 |
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T2= 7.66 _d 0 |
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QS1= 622. _d 0 |
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QS2= .378 _d 0 |
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|
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|
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IF (IMODE.EQ.2) THEN |
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C- Compute Qsat and d.Qsat/d.T : |
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DO J=1,NGP |
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QSAT(J)=0. |
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sigP = PS(1) |
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IF (SIG.GT.0.0) sigP=SIG*PS(J) |
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IF (TA(J).GE.T0) THEN |
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tmpQ = E0*EXP(C1*(TA(J)-T0)/(TA(J)-T1)) |
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QSAT(J)= QS1*tmpQ/(sigP-QS2*tmpQ) |
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recT = 1. _d 0 / (TA(J)-T1) |
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RH(J) = QSAT(J)*C1*(T0-T1)*recT*recT*sigP/(sigP-QS2*tmpQ) |
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ELSE IF ( TA(J).GT.T2) THEN |
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tmpQ = E0*EXP(C2*(TA(J)-T0)/(TA(J)-T2)) |
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QSAT(J)= QS1*tmpQ/(sigP-QS2*tmpQ) |
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recT = 1. _d 0 / (TA(J)-T2) |
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RH(J) = QSAT(J)*C2*(T0-T2)*recT*recT*sigP/(sigP-QS2*tmpQ) |
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ENDIF |
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ENDDO |
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RETURN |
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ENDIF |
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|
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DO 110 J=1,NGP |
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QSAT(J)=0. |
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IF (TA(J).GE.T0) THEN |
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QSAT(J)=E0*EXP(C1*(TA(J)-T0)/(TA(J)-T1)) |
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ELSE IF ( TA(J).GT.T2) THEN |
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QSAT(J)=E0*EXP(C2*(TA(J)-T0)/(TA(J)-T2)) |
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ENDIF |
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110 CONTINUE |
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C |
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IF (SIG.LE.0.0) THEN |
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DO 120 J=1,NGP |
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QSAT(J)= QS1*QSAT(J)/( PS(1) - QS2*QSAT(J)) |
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120 CONTINUE |
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ELSE |
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DO 130 J=1,NGP |
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QSAT(J)= QS1*QSAT(J)/(SIG*PS(J)- QS2*QSAT(J)) |
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130 CONTINUE |
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ENDIF |
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C |
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C--- 2. Compute rel.hum. RH=Q/Qsat (IMODE>0), or Q=RH*Qsat (IMODE<0) |
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C |
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IF (IMODE.GT.0) THEN |
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DO 210 J=1,NGP |
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IF(QSAT(J).NE.0.) then |
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RH(J)=QA(J)/QSAT(J) |
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ELSE |
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RH(J)=0. |
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ENDIF |
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210 CONTINUE |
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ELSE IF (IMODE.LT.0) THEN |
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DO 220 J=1,NGP |
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QA(J)=RH(J)*QSAT(J) |
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220 CONTINUE |
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ENDIF |
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|
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#endif /* ALLOW_AIM */ |
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RETURN |
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END |
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|
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SUBROUTINE ZMEDDY (NLON,NLAT,FF,ZM,EDDY) |
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|
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IMPLICIT NONE |
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|
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C *** Decompose a field into zonal-mean and eddy component |
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|
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C-- Routine arguments: |
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INTEGER NLON, NLAT |
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_RL FF(NLON,NLAT), ZM(NLAT), EDDY(NLON,NLAT) |
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|
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#ifdef ALLOW_AIM |
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|
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C-- Local variables: |
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INTEGER I,J |
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|
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C- jmc: declare all local variables: |
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_RL RNLON |
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C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
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|
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RNLON=1./NLON |
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C |
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DO 130 J=1,NLAT |
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C |
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ZM(J)=0. |
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DO 110 I=1,NLON |
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ZM(J)=ZM(J)+FF(I,J) |
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110 CONTINUE |
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ZM(J)=ZM(J)*RNLON |
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C |
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DO 120 I=1,NLON |
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EDDY(I,J)=FF(I,J)-ZM(J) |
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120 CONTINUE |
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C |
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130 CONTINUE |
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C |
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C-- |
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#endif /* ALLOW_AIM */ |
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|
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RETURN |
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END |