!-------------------------------------- LICENCE BEGIN ------------------------------------
!Environment Canada - Atmospheric Science and Technology License/Disclaimer,
! version 3; Last Modified: May 7, 2008.
!This is free but copyrighted software; you can use/redistribute/modify it under the terms
!of the Environment Canada - Atmospheric Science and Technology License/Disclaimer
!version 3 or (at your option) any later version that should be found at:
!http://collaboration.cmc.ec.gc.ca/science/rpn.comm/license.html
!
!This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
!without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
!See the above mentioned License/Disclaimer for more details.
!You should have received a copy of the License/Disclaimer along with this software;
!if not, you can write to: EC-RPN COMM Group, 2121 TransCanada, suite 500, Dorval (Quebec),
!CANADA, H9P 1J3; or send e-mail to service.rpn@ec.gc.ca
!-------------------------------------- LICENCE END --------------------------------------
***S/P RAYLEV - RAYLEIGH SCATTERING VISIBLE REGION
*
#include "phy_macros_f.h"
subroutine raylev (taur, ig, dp, rmu3, il1, il2, ilg, lay) 1
*
#include "impnone.cdk"
*
integer ilg, lay, ib, il1, il2, k, i, ig
real ri0(6), ri2(3), taur(ilg,lay), dp(ilg,lay), rmu3(ilg)
*
*Authors
*
* J. Li, M. Lazare, CCCMA, rt code for gcm4
* (Ref: J. Li, H. W. Barker, 2005:
* JAS Vol. 62, no. 2, pp. 286\226309)
* P. Vaillancourt, D. Talbot, RPN/CMC;
* adapted for CMC/RPN physics (May 2006)
*
*Revisions
* 001
*
*Object
*
* Rayleigh scattering for each sub-band in bands1, visible region
* taur is the optical depth rayleigh scattering for a given layer
* for uvc (35700 - 50000 cm^-1), since the optical depth of o3 and
* o2 are very large, rayleigh scattering effect is neglected, it
* is shown even for 10% o3 amount of the standard atmo, the
* rayleigh scattering for uvc still can be neglected.
* For par and uva, since their spectral ranges are very wide, small
* errors could occur for large zenith angle, slightly adjustment
* is needed, this does mean the rayleigh optical depth is related
* solar zenith angle for multiple scattering process in swtran.
*
*Arguments
*
* taur rayleigh optical depth
* dp air mass path for a model layer (explained in raddriv).
* rmu3 a factor of solar zenith angle, given in raddriv
*
**
data ri0 / .75996e-04, .20144e-03, .44813e-03, .80206e-03,
1 .10430e-02, .12756e-02 /
data ri2 / .38900e-05, .11500e-04, .19100e-04 /
c
if (ig .le. 3) then
do 100 k = 1, lay
do 100 i = il1, il2
taur(i,k) = (ri0(ig) - ri2(ig) * rmu3(i)) * dp(i,k)
100 continue
else
do 200 k = 1, lay
do 200 i = il1, il2
taur(i,k) = ri0(ig) * dp(i,k)
200 continue
endif
c
return
end