Changeset 600 for trunk/LMDZ.GENERIC/libf/phystd/sfluxi.F

Timestamp:

Mar 27, 2012, 5:02:10 PM (13 years ago)

Author:

jleconte

Message:

• Corrects the computation of planck function at the surface in sfluxi

so that its integral is equal to sigma Tsurf^4.

• This ensure that no flux is lost due to:

-truncation of the planck function at high/low wavenumber
-numerical error during first spectral computation of the planck function
-discrepancy between Tsurf and NTS/NTfac in sfluxi

• OLR now equal to LW net heating/cooling at equilibrium!
• As much as possible, only the value of the stephan boltzmann constant defined in racommon_h (and the

corresponding variable, sigma) should be used. Now done in physics, vdifc and turbdiff.

File:

• trunk/LMDZ.GENERIC/libf/phystd/sfluxi.F (modified) (3 diffs)

trunk/LMDZ.GENERIC/libf/phystd/sfluxi.F

@@ -5 +5 @@
 
       use radinc_h
-      use radcommon_h, only: planckir, tlimit
+      use radcommon_h, only: planckir, tlimit,sigma
 
       implicit none
@@ -33 +33 @@
 
       real*8 fup_tmp(L_NSPECTI),fdn_tmp(L_NSPECTI)
+      real*8 PLANCKSUM,PLANCKREF
 
 
@@ -72 +73 @@
 !      NTT   = TTOP *10.0D0-499
 
+!JL12 corrects the surface planck function so that its integral is equal to sigma Tsurf^4
+!JL12   this ensure that no flux is lost due to:
+!JL12          -truncation of the planck function at high/low wavenumber
+!JL12          -numerical error during first spectral integration
+!JL12          -discrepancy between Tsurf and NTS/NTfac
+      PLANCKSUM=0.d0
+      PLANCKREF=TSURF*TSURF
+      PLANCKREF=sigma*PLANCKREF*PLANCKREF
+      DO NW=1,L_NSPECTI
+         PLANCKSUM=PLANCKSUM+PLANCKIR(NW,NTS)*DWNI(NW)
+      ENDDO
+      PLANCKSUM=PLANCKREF/(PLANCKSUM*Pi)
+!JL12
+
       DO 501 NW=1,L_NSPECTI
 
 C       SURFACE EMISSIONS - INDEPENDENT OF GAUSS POINTS
-        BSURF = (1.-RSFI)*PLANCKIR(NW,NTS) ! interpolate for accuracy??
+        BSURF = (1.-RSFI)*PLANCKIR(NW,NTS)*PLANCKSUM !JL12 plancksum see above
         PLTOP = PLANCKIR(NW,NTT)