solar radaiation

[Fatima]

Dear all,
I want to add The decay law for the flux of solar radiation in my model. As you know, it reduces with depth exponentially.
I = I0 * e^(-k*d)
where I is the intensity of solar radiation at a given depth in the water, I0 is the intensity of radiation at the surface of the ice, k is the attenuation coefficient.
How I can define it.

I also keep my water surface temperature equal to zero during running time.
I try to define a constant surface flux in ana_stflux, but my model crashed.
Thank you in advance.
Best regards,

[wilkin]

This code already exists ... #define SOLAR_SOURCE. The work is done in Nonlinear/lmd_swfrac.F using two length scales according to the method of Paulson and Simpson (1977) https://doi.org/10.1175/1520-0485(1977) ... 3E2.0.CO;2

The user chooses the length scales with the water type WTYPE parameter in roms.in

Scroll down to the Glossary at the end of roms.in and you will see:

Code: Select all

!------------------------------------------------------------------------------
! Jerlov Water type.
!------------------------------------------------------------------------------
!
! WTYPE        Jerlov water type array index used to model the light absorption
!                with a double exponential function (Paulson and Simpson,
!                1977).  The classification ranges from clear open ocean
!                waters (type I) to dark turbulent coastal waters (type 7).
!
!              Array     Jerlov
!              Index   Water Type   Examples
!              -----   ----------   --------
!
!                1         I        Open Pacific
!                2         IA       Eastern Mediterranean, Indian Ocean
!                3         IB       Western Mediterranean, Open Atlantic
!                4         II       Coastal waters, Azores
!                5         III      Coastal waters, North Sea
!                6         1        Skagerrak Strait
!                7         3        Baltic
!                8         5        Black Sea
!                9         7        Dark coastal water

To see what the length scales are, they are coded in Modules/mod_scalars.F in the block ...

Code: Select all

#if defined LMD_SKPP || defined SOLAR_SOURCE
!
!-----------------------------------------------------------------------
!  Water clarity parameters.
!-----------------------------------------------------------------------
!
!  The water type classification is based on Jerlov water type using
!  a double exponential function for light absorption:
!
!    Array
!    Index   WaterType   Examples
!    -----   ---------   --------
!
!      1         I       Open Pacific
!      2         IA      Eastern Mediterranean, Indian Ocean
!      3         IB      Western Mediterranean, Open Atlantic
!      4         II      Coastal waters, Azores
!      5         III     Coastal waters, North Sea
!      6         1       Skagerrak Strait
!      7         3       Baltic
!      8         5       Black Sea
!      9         7       Dark coastal water
!
!    lmd_mu1       Reciprocal of the absorption coefficient for solar
!                    wavelength band 1 as a function of the Jerlov
!                    water type.
!    lmd_mu2       Reciprocal of the absorption coefficient for solar
!                    wavelength band 2 as a function of the Jerlov
!                    water type.
!    lmd_r1        Fraction of total radiance for wavelength band 1 as
!                    a function of the Jerlov water type.
!
        real(r8), dimension(9) :: lmd_mu1 =                             &
     &            (/ 0.35_r8, 0.6_r8,  1.0_r8,  1.5_r8, 1.4_r8,         &
     &               0.42_r8, 0.37_r8, 0.33_r8, 0.00468592_r8 /)

        real(r8), dimension(9) :: lmd_mu2 =                             &
     &            (/ 23.0_r8,  20.0_r8,  17.0_r8,  14.0_r8, 7.9_r8,     &
     &                5.13_r8,  3.54_r8,  2.34_r8,  1.51_r8 /)

        real(r8), dimension(9) :: lmd_r1 =                              &
     &            (/ 0.58_r8, 0.62_r8, 0.67_r8, 0.77_r8, 0.78_r8,       &
     &               0.57_r8, 0.57_r8, 0.57_r8, 0.55_r8 /)
#endif