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SURFEX v7.3
General documentation of Surfex
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SURFEX v7.3
General documentation of Surfex
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00001 ! ######### 00002 SUBROUTINE SOIL_TEMP_ARP(PTSTEP,PA,PB,PC,PGAMMAT,PTDEEP,PSODELX,PTG) 00003 ! ############################################################ 00004 ! 00005 !!**** *SOIL_TEMP_ARP* 00006 ! 00007 !! PURPOSE 00008 !! ------- 00009 ! This subroutine solves the ARPEGE 1-d surface and deep force-restore 00010 ! 'PTG' using the backward-difference scheme (implicit) as in soil_heatdiff. 00011 ! The eqs are solved rapidly by taking advantage of the 00012 ! fact that the matrix is tridiagonal. Soln to the eqs: 00013 ! 00014 ! dTi S1 00015 ! --- = Ct -- (Gi - Gi+1) 00016 ! dt Si 00017 ! 00018 ! with | G1 = Rn-H-LE 00019 ! | 00020 ! | 2Pi 1 00021 ! | Gi = ------ -------------- (Ti-1 - Ti) 00022 ! | Ct*Day S1 (Si-1 + Si) 00023 ! 00024 ! 00025 ! where Si = pulsation depth, i=1 is the surface 00026 ! 00027 !!** METHOD 00028 !! ------ 00029 ! 00030 ! Direct calculation 00031 ! 00032 !! EXTERNAL 00033 !! -------- 00034 ! 00035 ! None 00036 !! 00037 !! IMPLICIT ARGUMENTS 00038 !! ------------------ 00039 !! 00040 !! USE MODD_SURF_PAR 00041 !! USE MODI_TRIDIAG_GROUND 00042 !! 00043 !! REFERENCE 00044 !! --------- 00045 !! 00046 !! AUTHOR 00047 !! ------ 00048 !! B. Decharme * Meteo-France * 00049 !! 00050 !! MODIFICATIONS 00051 !! ------------- 00052 !! Original 21/01/09 B. Decharme 00053 ! 00054 !------------------------------------------------------------------------------- 00055 ! 00056 !* 0. DECLARATIONS 00057 ! ------------ 00058 ! 00059 USE MODD_CSTS, ONLY : XPI, XDAY 00060 ! 00061 USE MODD_SURF_PAR, ONLY : XUNDEF 00062 ! 00063 USE MODI_TRIDIAG_GROUND 00064 ! 00065 ! 00066 USE YOMHOOK ,ONLY : LHOOK, DR_HOOK 00067 USE PARKIND1 ,ONLY : JPRB 00068 ! 00069 IMPLICIT NONE 00070 ! 00071 ! 00072 REAL, INTENT(IN) :: PTSTEP ! Model time step (s) 00073 ! 00074 REAL, DIMENSION(:), INTENT(IN) :: PA,PB,PC ! terms for the linearization of Ts(t) 00075 ! 00076 REAL, DIMENSION(:), INTENT(IN) :: PTDEEP, PGAMMAT 00077 ! PTDEEP = Deep soil temperature (prescribed) 00078 ! which models heating/cooling from 00079 ! below the diurnal wave penetration 00080 ! (surface temperature) depth. 00081 ! PGAMMAT = Deep soil heat transfer coefficient: 00082 ! assuming homogeneous soil so that 00083 ! this can be prescribed in units of 00084 ! (1/days): associated time scale with 00085 ! PTDEEP. 00086 REAL, DIMENSION(:), INTENT (IN) :: PSODELX ! Pulsation for each layer (Only used if LTEMP_ARP=True) 00087 ! 00088 REAL, DIMENSION(:,:), INTENT(INOUT) :: PTG 00089 ! PTG = soil temperature (K) 00090 ! 00091 ! 00092 !* 0.2 declarations of local variables 00093 ! 00094 INTEGER :: JJ ! Loop counter 00095 ! 00096 INTEGER :: INLVLD ! Number of points and grid layers 00097 ! 00098 REAL, DIMENSION(SIZE(PTG,1),SIZE(PTG,2)) :: ZTGM, ZFRCV, ZAMTRX, ZBMTRX, 00099 ZCMTRX, ZLAMBDA, ZALPHA 00100 REAL(KIND=JPRB) :: ZHOOK_HANDLE 00101 ! 00102 !------------------------------------------------------------------------------- 00103 ! 00104 ! Initialize local variables: 00105 ! 00106 IF (LHOOK) CALL DR_HOOK('SOIL_TEMP_ARP',0,ZHOOK_HANDLE) 00107 INLVLD = SIZE(PTG(:,:),2) 00108 ! 00109 ZTGM(:,:) = PTG(:,:) 00110 ! 00111 ZFRCV (:,:) = 0.0 00112 ZAMTRX (:,:) = 0.0 00113 ZBMTRX (:,:) = 0.0 00114 ZCMTRX (:,:) = 0.0 00115 ZALPHA (:,:) = 0.0 00116 ZLAMBDA(:,:) = 0.0 00117 ! 00118 !------------------------------------------------------------------------------- 00119 ! 00120 ! Calculate tri-diagonal matrix coefficients: 00121 ! 00122 ! 00123 DO JJ=1,INLVLD-1 00124 ZALPHA (:,JJ) = PSODELX(JJ)*XDAY/(PTSTEP*PSODELX(1)*2.0*XPI) 00125 ZLAMBDA(:,JJ) = 1.0/(PSODELX(1)*(PSODELX(JJ)+PSODELX(JJ+1))) 00126 ENDDO 00127 ZALPHA(:,INLVLD) = PSODELX(INLVLD)*XDAY/(PTSTEP*PSODELX(1)*2.0*XPI) 00128 ! 00129 !------------------------------------------------------------------------------- 00130 ! 00131 ! Upper BC 00132 ! 00133 ZAMTRX(:,1) = 0.0 00134 ZBMTRX(:,1) = PA(:)+(2.0*XPI/XDAY)*(1.0/(PSODELX(1)*(PSODELX(1)+PSODELX(2)))-1.0) 00135 ZCMTRX(:,1) = -2.0*XPI/(XDAY*PSODELX(1)*(PSODELX(1)+PSODELX(2))) 00136 ZFRCV (:,1) = PB(:)*ZTGM(:,1)+PC(:)-2.0*XPI*ZTGM(:,2)/XDAY 00137 ! 00138 ! 00139 ! Interior Grid 00140 ! 00141 DO JJ=2,INLVLD-1 00142 ZAMTRX(:,JJ) = -ZLAMBDA(:,JJ-1) 00143 ZBMTRX(:,JJ) = ZALPHA(:,JJ) + ZLAMBDA(:,JJ-1) + ZLAMBDA(:,JJ) 00144 ZCMTRX(:,JJ) = -ZLAMBDA(:,JJ) 00145 ZFRCV(:,JJ) = ZALPHA(:,JJ)*ZTGM(:,JJ) 00146 ENDDO 00147 ! 00148 ! Lower BC: 2 currently accounted for, Either zero flux 00149 ! or a fixed temperature 'TDEEP' 00150 ! 00151 ZAMTRX(:,INLVLD) = -ZLAMBDA(:,INLVLD-1) 00152 ZCMTRX(:,INLVLD) = 0.0 00153 ! 00154 WHERE(PTDEEP(:) /= XUNDEF .AND. PGAMMAT(:) /= XUNDEF) 00155 ZBMTRX(:,INLVLD) = ZALPHA(:,INLVLD) + ZLAMBDA(:,INLVLD-1) + PTSTEP*PGAMMAT(:)/XDAY 00156 ZFRCV (:,INLVLD) = ZALPHA(:,INLVLD)*ZTGM(:,INLVLD) + PTSTEP*PGAMMAT(:)*PTDEEP(:)/XDAY 00157 ELSEWHERE 00158 ZBMTRX(:,INLVLD) = ZALPHA(:,INLVLD) + ZLAMBDA(:,INLVLD-1) 00159 ZFRCV (:,INLVLD) = ZALPHA(:,INLVLD)*ZTGM(:,INLVLD) 00160 END WHERE 00161 ! 00162 !------------------------------------------------------------------------------- 00163 ! 00164 ! Compute ZTGM (solution vector) 00165 ! used for systems of equations involving tridiagonal 00166 ! matricies. 00167 ! 00168 CALL TRIDIAG_GROUND(ZAMTRX,ZBMTRX,ZCMTRX,ZFRCV,ZTGM) 00169 ! 00170 ! Update values in time: 00171 ! 00172 PTG(:,:) = ZTGM(:,:) 00173 ! 00174 IF (LHOOK) CALL DR_HOOK('SOIL_TEMP_ARP',1,ZHOOK_HANDLE) 00175 ! 00176 !------------------------------------------------------------------------------- 00177 ! 00178 END SUBROUTINE SOIL_TEMP_ARP
1.8.0
