*IF DEF,A19_2A TRIFD2A.2
C *****************************COPYRIGHT****************************** TRIFD2A.3
C (c) CROWN COPYRIGHT 1997, METEOROLOGICAL OFFICE, All Rights Reserved. TRIFD2A.4
C TRIFD2A.5
C Use, duplication or disclosure of this code is subject to the TRIFD2A.6
C restrictions as set forth in the contract. TRIFD2A.7
C TRIFD2A.8
C Meteorological Office TRIFD2A.9
C London Road TRIFD2A.10
C BRACKNELL TRIFD2A.11
C Berkshire UK TRIFD2A.12
C RG12 2SZ TRIFD2A.13
C TRIFD2A.14
C If no contract has been raised with this copy of the code, the use, TRIFD2A.15
C duplication or disclosure of it is strictly prohibited. Permission TRIFD2A.16
C to do so must first be obtained in writing from the Head of Numerical TRIFD2A.17
C Modelling at the above address. TRIFD2A.18
C ******************************COPYRIGHT****************************** TRIFD2A.19
!!! Subroutine TRIFFID ------------------------------------------------ TRIFD2A.20
!!! TRIFD2A.21
!!! Top-down TRIFD2A.22
!!! Representation of TRIFD2A.23
!!! Interactive TRIFD2A.24
!!! Foliage and TRIFD2A.25
!!! Flora TRIFD2A.26
!!! Including TRIFD2A.27
!!! Dynamics TRIFD2A.28
!!! TRIFD2A.29
!!! Purpose : Simulates changes in vegetation structure, areal TRIFD2A.30
!!! coverage and the carbon contents of vegetation and soil. TRIFD2A.31
!!! can be used to advance these variables dynamically TRIFD2A.32
!!! (GAMMA=1/TIMESTEP) or to iterate towards equilibrium TRIFD2A.33
!!! (GAMMA --> 0.0, FORW=1.0). ABX1F405.1587
!!! TRIFD2A.35
!!! TRIFD2A.36
!!! Model Modification history: TRIFD2A.37
!!! version Date TRIFD2A.38
!!! 4.4 10/97 New Deck. Peter Cox TRIFD2A.39
!!! 4.5 12/05/98 Operate only on points indexed with TRIF_INDEX. ABX1F405.1588
!!! Richard Betts ABX1F405.1589
!!! TRIFD2A.40
!!!END ---------------------------------------------------------------- TRIFD2A.41
SUBROUTINE TRIFFID (LAND_FIELD,TRIF_PTS,TRIF_INDEX,FORW,GAMMA 1,3ABX1F405.1590
&, FRAC_VS,G_ANTH,G_LEAF,NPP,RESP_S,RESP_W ABX1F405.1591
&, CS,FRAC,HT,LAI,C_VEG,CV,LIT_C,LIT_C_T) TRIFD2A.44
TRIFD2A.45
TRIFD2A.46
IMPLICIT NONE TRIFD2A.47
TRIFD2A.48
*CALL NSTYPES 
TRIFD2A.49
TRIFD2A.50
INTEGER TRIFD2A.51
& LAND_FIELD ! IN Total number of land points. TRIFD2A.52
&,TRIF_PTS ! IN Number of points on which ABX1F405.1592
! ! TRIFFID may operate ABX1F405.1593
&,TRIF_INDEX(LAND_FIELD) ! IN Indices of land points on ABX1F405.1594
! ! which TRIFFID may operate ABX1F405.1595
&,L,N,T ! WORK Loop counters ABX1F405.1596
TRIFD2A.57
REAL TRIFD2A.58
& FORW ! IN Forward timestep weighting. TRIFD2A.59
&,FRAC_VS(LAND_FIELD) ! IN Total fraction of gridbox ABX1F405.1597
! ! covered by veg or soil. ABX1F405.1598
&,GAMMA ! IN Inverse timestep (/360days). ABX1F405.1599
&,G_ANTH(LAND_FIELD) ! IN Anthropogenic disturbance rate TRIFD2A.61
C ! (/360days). ABX1F405.1600
&,G_LEAF(LAND_FIELD,NPFT) ! IN Turnover rate for leaf and TRIFD2A.63
C ! fine root biomass (/360days). ABX1F405.1601
&,NPP(LAND_FIELD,NPFT) ! INOUT Net primary productivity TRIFD2A.65
C ! (kg C/m2/360days). ABX1F405.1602
&,RESP_S(LAND_FIELD) ! INOUT Soil respiration ABX1F405.1603
C ! (kg C/m2/360days). ABX1F405.1604
&,RESP_W(LAND_FIELD,NPFT) ! INOUT Wood maintenance respiration TRIFD2A.68
C ! (kg C/m2/360days). ABX1F405.1605
&,CS(LAND_FIELD) ! INOUT Soil carbon (kg C/m2). TRIFD2A.70
&,FRAC(LAND_FIELD,NTYPE) ! INOUT Fractional cover of each TRIFD2A.71
C ! Functional Type. TRIFD2A.72
&,HT(LAND_FIELD,NPFT) ! INOUT Vegetation height (m). TRIFD2A.73
&,LAI(LAND_FIELD,NPFT) ! INOUT Leaf area index. TRIFD2A.74
&,C_VEG(LAND_FIELD,NPFT) ! OUT Total carbon content of TRIFD2A.75
C ! the vegetation (kg C/m2). TRIFD2A.76
&,CV(LAND_FIELD) ! OUT Gridbox mean vegetation TRIFD2A.77
C ! carbon (kg C/m2). TRIFD2A.78
&,LIT_C(LAND_FIELD,NPFT) ! OUT Carbon Litter (kg C/m2/360days). ABX1F405.1606
&,LIT_C_T(LAND_FIELD) ! OUT Gridbox mean carbon litter TRIFD2A.80
C ! (kg C/m2/360days). ABX1F405.1607
TRIFD2A.82
REAL TRIFD2A.83
& DCVEG(LAND_FIELD,NPFT) ! WORK Change in vegetation carbon TRIFD2A.84
C ! during the timestep TRIFD2A.85
C ! (kg C/m2/timestep). TRIFD2A.86
&,DFRAC(LAND_FIELD,NPFT) ! WORK Change in areal fraction TRIFD2A.87
C ! during the timestep TRIFD2A.88
C ! (/timestep). TRIFD2A.89
&,LAI_BAL(LAND_FIELD,NPFT) ! WORK Leaf area index in balanced TRIFD2A.90
C ! growth state. TRIFD2A.91
&,LEAF(LAND_FIELD,NPFT) ! WORK Leaf biomass (kg C/m2). TRIFD2A.92
&,PC_S(LAND_FIELD,NPFT) ! WORK Net carbon flux available TRIFD2A.93
C ! for spreading ABX1F405.1608
C ! (kg C/m2/yr). ABX1F405.1609
&,PHEN(LAND_FIELD,NPFT) ! WORK Phenological state. TRIFD2A.95
&,ROOT(LAND_FIELD,NPFT) ! WORK Root biomass (kg C/m2). TRIFD2A.96
&,WOOD(LAND_FIELD,NPFT) ! WORK Woody biomass (kg C/m2). TRIFD2A.97
TRIFD2A.98
*CALL TRIF TRIFD2A.99
TRIFD2A.100
C---------------------------------------------------------------------- TRIFD2A.101
C Loop through Functional Types TRIFD2A.102
C---------------------------------------------------------------------- TRIFD2A.103
DO N=1,NPFT TRIFD2A.104
TRIFD2A.105
C---------------------------------------------------------------------- TRIFD2A.106
C Loop through TRIFFID points ABX1F405.1610
C---------------------------------------------------------------------- TRIFD2A.108
DO T=1,TRIF_PTS ABX1F405.1611
L=TRIF_INDEX(T) ABX1F405.1612
TRIFD2A.110
C---------------------------------------------------------------------- TRIFD2A.111
C Diagnose the balanced-growth leaf area index and the associated leaf, TRIFD2A.112
C wood, root and total vegetation carbon TRIFD2A.113
C---------------------------------------------------------------------- TRIFD2A.114
LAI_BAL(L,N) = (A_WS(N)*ETA_SL(N)*HT(L,N) TRIFD2A.115
& /A_WL(N))**(1.0/(B_WL(N)-1)) TRIFD2A.116
LEAF(L,N) = SIGL(N)*LAI_BAL(L,N) TRIFD2A.117
ROOT(L,N) = LEAF(L,N) TRIFD2A.118
WOOD(L,N) = A_WL(N)*(LAI_BAL(L,N)**B_WL(N)) TRIFD2A.119
C_VEG(L,N) = LEAF(L,N) + ROOT(L,N) + WOOD(L,N) TRIFD2A.120
C---------------------------------------------------------------------- TRIFD2A.121
C Diagnose the phenological state TRIFD2A.122
C---------------------------------------------------------------------- TRIFD2A.123
PHEN(L,N) = LAI(L,N)/LAI_BAL(L,N) TRIFD2A.124
TRIFD2A.125
ENDDO TRIFD2A.126
TRIFD2A.127
C---------------------------------------------------------------------- TRIFD2A.128
C Update vegetation carbon contents TRIFD2A.129
C---------------------------------------------------------------------- TRIFD2A.130
CALL VEGCARB (LAND_FIELD,TRIF_PTS,TRIF_INDEX,N,FORW ABX1F405.1613
&, GAMMA,G_LEAF(1,N),NPP(1,N),RESP_W(1,N) ABX1F405.1614
&, LEAF(1,N),ROOT(1,N),WOOD(1,N) TRIFD2A.133
&, DCVEG(1,N),PC_S(1,N)) TRIFD2A.134
TRIFD2A.135
ENDDO TRIFD2A.136
TRIFD2A.137
C----------------------------------------------------------------------- TRIFD2A.138
C Diagnose the new value of Canopy Height, Leaf Area Index and Total TRIFD2A.139
C Vegetation Carbon TRIFD2A.140
C----------------------------------------------------------------------- TRIFD2A.141
DO N=1,NPFT TRIFD2A.142
TRIFD2A.143
DO T=1,TRIF_PTS ABX1F405.1615
L=TRIF_INDEX(T) ABX1F405.1616
TRIFD2A.145
HT(L,N) = WOOD(L,N) / (A_WS(N) * ETA_SL(N)) TRIFD2A.146
& * (A_WL(N)/WOOD(L,N))**(1.0/B_WL(N)) TRIFD2A.147
LAI_BAL(L,N) = LEAF(L,N) / SIGL(N) TRIFD2A.148
LAI(L,N) = PHEN(L,N) * LAI_BAL(L,N) TRIFD2A.149
C_VEG(L,N) = LEAF(L,N) + ROOT(L,N) + WOOD(L,N) TRIFD2A.150
TRIFD2A.151
ENDDO TRIFD2A.152
TRIFD2A.153
ENDDO TRIFD2A.154
TRIFD2A.155
C---------------------------------------------------------------------- TRIFD2A.156
C Update the areal coverage of each functional type TRIFD2A.157
C---------------------------------------------------------------------- TRIFD2A.158
CALL LOTKA (LAND_FIELD,TRIF_PTS,TRIF_INDEX ABX1F405.1617
&, C_VEG,FORW,FRAC_VS,GAMMA,G_ANTH,LAI_BAL,PC_S ABX1F405.1618
&, FRAC,DFRAC) TRIFD2A.161
TRIFD2A.162
C---------------------------------------------------------------------- TRIFD2A.163
C Diagnose the litterfall from the carbon balance of each vegetation TRIFD2A.164
C type (assumes explicit update). TRIFD2A.165
C---------------------------------------------------------------------- TRIFD2A.166
DO T=1,TRIF_PTS ABX1F405.1619
L=TRIF_INDEX(T) ABX1F405.1620
TRIFD2A.168
LIT_C_T(L) = 0.0 TRIFD2A.169
TRIFD2A.170
DO N=1,NPFT TRIFD2A.171
LIT_C(L,N) = NPP(L,N)-GAMMA*(C_VEG(L,N)*FRAC(L,N) TRIFD2A.172
& -(C_VEG(L,N)-DCVEG(L,N))*(FRAC(L,N)-DFRAC(L,N)))/FRAC(L,N) TRIFD2A.173
LIT_C_T(L) = LIT_C_T(L)+FRAC(L,N)*LIT_C(L,N) TRIFD2A.174
ENDDO TRIFD2A.175
ENDDO TRIFD2A.176
TRIFD2A.177
C---------------------------------------------------------------------- TRIFD2A.178
C Call SOIL_C to update the soil carbon content TRIFD2A.179
C---------------------------------------------------------------------- TRIFD2A.180
CALL SOILCARB (LAND_FIELD,TRIF_PTS,TRIF_INDEX ABX1F405.1621
&, FORW,GAMMA,LIT_C_T,RESP_S,CS) ABX1F405.1622
TRIFD2A.183
C---------------------------------------------------------------------- TRIFD2A.184
C Diagnose the gridbox mean vegetation carbon TRIFD2A.185
C---------------------------------------------------------------------- TRIFD2A.186
DO T=1,TRIF_PTS ABX1F405.1623
L=TRIF_INDEX(T) ABX1F405.1624
CV(L) = 0.0 TRIFD2A.188
DO N=1,NPFT TRIFD2A.189
CV(L) = CV(L)+FRAC(L,N)*C_VEG(L,N) TRIFD2A.190
ENDDO TRIFD2A.191
ENDDO TRIFD2A.192
TRIFD2A.193
RETURN TRIFD2A.194
END TRIFD2A.195
*ENDIF TRIFD2A.196