Changeset 1987

Timestamp:

Aug 28, 2018, 12:15:19 PM (6 years ago)

Author:

jleconte

Message:

28/08/2018 == JL

Start a series of commits to change the upper boundary conditions in the radiative transfer to solve some issues with the last two layers.
It seems to be good to have aerosols in the first "radiative layer" of the gcm in the IR but visible does not handle very well diffusion in first layer.
Tauaero and tauray are set to 0 (a small value for rayleigh because the code crashes otherwise) in the 4 first semilayers in optcv, but not optci.
This solves random variations of the sw heating at the model top.

Location:

trunk/LMDZ.GENERIC

Files:

• README (modified) (1 diff)
• libf/phystd/optcv.F90 (modified) (4 diffs)

trunk/LMDZ.GENERIC/README

@@ -1372 +1372 @@
 == 31/07/2018 == EM
 Follow-up of change in maximum length of tracer names in the dynamics
+
+== 28/08/2018 == JL
+Start a series of commits to change the upper boundary conditions in the radiative transfer to solve some issues with the last two layers.
+It seems to be good to have aerosols in the first "radiative layer" of the gcm in the IR but visible does not handle very well diffusion in first layer.
+Tauaero and tauray are set to 0 (a small value for rayleigh because the code crashes otherwise) in the 4 first semilayers in optcv, but not optci. 
+This solves random variations of the sw heating at the model top. 

trunk/LMDZ.GENERIC/libf/phystd/optcv.F90

@@ -128 +128 @@
 
   ! Spectral dependance of aerosol absorption
+            !JL18 It seems to be good to have aerosols in the first "radiative layer" of the gcm in the IR
+            !   but visible does not handle very well diffusion in first layer.
+            !   The tauaero and tauray are thus set to 0 (a small value for rayleigh because the code crashes otherwise)
+            !   in the 4 first semilayers in optcv, but not optci.
+            !   This solves random variations of the sw heating at the model top. 
   do iaer=1,naerkind
      do NW=1,L_NSPECTV
-        do K=2,L_LEVELS
+        TAEROS(1:4,NW,IAER)=0.d0
+        do K=5,L_LEVELS
            TAEROS(K,NW,IAER) = TAUAERO(K,IAER) * QXVAER(K,NW,IAER)
         end do                    ! levels
@@ -138 +144 @@
   ! Rayleigh scattering
   do NW=1,L_NSPECTV
-     do K=2,L_LEVELS
+     TRAY(1:4,NW)   = 1d-30
+     do K=5,L_LEVELS
         TRAY(K,NW)   = TAURAY(NW) * DPR(K)
      end do                    ! levels
@@ -289 +296 @@
   !     we need to calculate the scattering albedo and asymmetry factors
 
+            !JL18 It seems to be good to have aerosols in the first "radiative layer" of the gcm in the IR
+            !   but not in the visible
+            !   The tauaero is thus set to 0 in the 4 first semilayers in optcv, but not optci.
+            !   This solves random variations of the sw heating at the model top. 
   do iaer=1,naerkind
     DO NW=1,L_NSPECTV
-      DO K=2,L_LEVELS
+      TAUAEROLK(1:4,NW,IAER)=0.d0
+      DO K=5,L_LEVELS
            TAUAEROLK(K,NW,IAER) = TAUAERO(K,IAER) * QSVAER(K,NW,IAER) ! effect of scattering albedo
       ENDDO
@@ -344 +356 @@
   DO NG=1,L_NGAUSS       ! full gauss loop
      DO NW=1,L_NSPECTV       
-        TAUV(1,NW,NG)=0.0D0
-        DO L=1,L_NLAYRAD
-           TAUV(L+1,NW,NG)=TAUV(L,NW,NG)+DTAUV(L,NW,NG)
-        END DO
-
         TAUCUMV(1,NW,NG)=0.0D0
         DO K=2,L_LEVELS
            TAUCUMV(K,NW,NG)=TAUCUMV(K-1,NW,NG)+DTAUKV(K,NW,NG)
         END DO
+
+        DO L=1,L_NLAYRAD+1
+           TAUV(L,NW,NG)=TAUCUMV(2*L,NW,NG)
+        END DO
      END DO            
   END DO                 ! end full gauss loop