Error in Ice albedo and shortwave flux in ROMS Native Sea Ice model?

[gen3]

Hi all,

I feel like that there is potential error in ROMS Native Sea Ice model for description of sea ice albedo and short wave flux at the water surface.

I was checking whether the ROMS Native Sea Ice model resolves light reflection and attenuation by sea ice.

And looks like that there is no sea ice light reflection term in the code, in terms of short wave radiation.

Below are the code for L1168-1188 of "Nonlinear/bulk_flux.F" (https://github.com/myroms/roms/blob/dev ... 1-L1188C65; presumed that this is the latest version of ROMS);

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# if defined ALBEDO && defined SHORTWAVE
!!        srflx(i,j) = srflx(i,j)*(1.0_r8-albedo(i,j))
# endif
# if defined ICE_MODEL && defined ICE_BULK_FLUXES
!
!  Limit shortwave radiation to be used in computing penetrative
!  radiation by presence of ice alone.
!
          cff1=1.0_r8/(Si(i,j,li_stp,isAice)+eps)
          ice_thick(i,j) =Si(i,j,li_stp,isHice)*cff1
          snow_thick(i,j)=Si(i,j,li_stp,isHsno)*cff1

          IF (ice_thick(i,j).le.0.1_r8) THEN
            cff2=ice_thick(i,j)*5.0_r8
          ELSE
            cff2=0.1_r8*(5.0_r8+(ice_thick(i,j)-0.1_r8))
          ENDIF

          cff2=cff2+snow_thick(i,j)*20.0_r8
          srflx(i,j)=(1.0_r8-Si(i,j,li_stp,isAice))*srflx(i,j)+         &
     &               Si(i,j,li_stp,isAice)*srflx(i,j)*EXP(-cff2)

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I can see the light attenuation terms at the end of the lines (L1187-1188) but light reflectance term looks like be commented (L1169).

I checked a possibility for that the light reflectance term exists in the other file, but I cannot find it to the best of my knowledge...

In my understanding, the first three lines need to be

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# if defined ICE_ALBEDO
        srflx(i,j) = srflx(i,j)*(1.0_r8-albedo_ice(i,j))
# endif

something like this way... This is important when we use marine ecosystem models...

I might be wrong, so correction for my understanding, or any comments, will be really appreciated.


Best regards,

Jang