This page is for documenting how CO2 is handleded in GSO.
The H2 run uses a CO2 value of "-6" in the rundeck. What does this mean?
PBAO23M12_RVX.f
Located at: source:GCM/GSO/trunk/code/PBAO23M12_RVX.f
KTREND=-CO2 3552.92
IF(KTREND.LE.0) GO TO 50 3552.94
TREF=1980. 3552.95
CALL SETGHG (TREF,KTREND,1,0) 3552.96
CALL GETGHG (TREF,1,0) 3552.98
50 JDAYR=0 3552.99
CALL RCOMP1 (21,0,0) 3553.
C-OLD CALL SETFOR(1,40,41) ! kWRITE,DesertDust file,1st Aerosol file 3553.1
KSOLAR=2 3553.41
FMUV1=1. 3553.42
FMUV2=1. 3553.43
FMUV3=1. 3553.44
FMTOT=1. 3553.45
C-- LTREND=0 ! not implemented yet 3553.46
S00WM2=1367.*S0X 3553.5
CALL SETSOL(2,33) ! kWrite IUNIT 3553.6
CALL WRITER (1,0) 3554.
CALL SPARES 3554.1
RETURN 3555. That is pretty much every mention of CO2 or KTREND in this file.
RF98C.f
located at source:GCM/GSO/trunk/code/RF98C.f
CO2
RF98C.f says:
C----------------------------------------------------------------------- 920. C T-GAS SCENARIO A: PRESENT TREND FOR TRACE GAS INCREASES 921. C EXPONENTIAL FORCING PROJECTED BEYOND 2000 922. C 923. C CO2: OBSERVED TREND 1958-1984, 924. C 0.015/YR RATE OF INCREASE 925. C ON 1.5 PPM INCREMENT BEYOND 1984 926.
And this is implemented in code as:
C CO2 SCENARIOS 965. C------------------------------------------------------------------- 966. 100 N=1 967. IF(YEAR.GT.1958.0) GO TO 110 968. DT=(YEAR-1850.0)/(1958.0-1850.0) 969. XX=270.0*(315.0/270.0)**DT 970. GO TO 120 971. 110 IF(YEAR.GT.1984.0) GO TO 115 972. I=YEAR 973. DELTA=YEAR-I 974. I=I-1957 975. XX=XXCO2(I)+DELTA*(XXCO2(I+1)-XXCO2(I)) 976. GO TO 120 977. 115 DT=YEAR-1984.0 978. XX0=343.81 979. ETA=1.50 980. XMU=0.015 981. XX=XX0+ETA*(EXP(XMU*DT)-1.0)/XMU 982. 120 CONTINUE 983. XGAS(N)=XX 984.
Likewise, there is a SCENARIO B:
C-----------------------------------------------------------------------1086. C T-GAS SCENARIO B: REDUCED TREND FOR TRACE GAS INCREASES 1087. C REDUCED FORCING BEYOND 2000) 1088. C 1089. C CO2: OBSERVED TREND 1958-1984, 1090. C 0.015/YR INCREASE IN 1.5 PPM INCREMENT 1091. C THRU 1990, 0.010/YR THRU 2000, 0.005/YR 1092. C 2010, CONSTANT INCREMENT BEYOND 2010 1093. C 1094.
And a SCENARIO C and F too.
KTREND
Also, KTREND is used. Of interest is line 552
IF(KTREND.EQ.6) CALL FTREND(XREF,TREF,NGAS) 808.3
and line 634
IF(KTREND.EQ.6) CALL FTREND(XNOW,TNOW,NGAS) 883.3
