E1850C5CN compset SOLAR DATA FILE in &solar_inparm

[amatcaos@caos_iisc_ernet_in]

Hello,I am using the E compset E1850C5CN. I do not understand the NAMELIST variable 'solar data file'. How this data file is related to the Solar constant (whose default value I suppose is 1367W/m2). Say I change the solar constant value to 1360W/m2, then do I need to modify the default solar data file: SOLAR_SPECTRAL_Lean_1610-2008_annual_c090324.ncFurther, I checked the Fcompset FG1850CN and one of the Bcompset B1850CN for the solar data file. But its not a default namelist parameter under solar_inparm group. So, why it is a defualt namelist parameter in this E compset. I'll be grateful if somebody can inform me about this issue related to solar-inparm name list parameters.Many ThanksAngshuman

 

[eaton]

E1850C5CN is using the cam5 physics package which includes the RRTMG radiation package.  RRTMG uses spectral information which comes from the solar_data_file.  When solar_data_file is specified then the value of solar_const is ignored.  I believe it is possible to use RRTMG and only specify solar_const, but in that case the setting for solar_data_file must be removed.
The other compsets you mentioned use the cam4 physics package which includes the old radiation code and only uses the solar_const value as input.The upcoming release fixes this confusion by not allowing solar_const to be specified in instances where it will be ignored. 

 

[amatcaos@caos_iisc_ernet_in]

Dear EatonAs per your suggestion I removed the solar_data_file from the cam.buildnml.csh file.The namelist looks like this:...&rad_cnst_nl
 icecldoptics           = 'mitchell'
 iceopticsfile          = '$DIN_LOC_ROOT/atm/cam/physprops/iceoptics_c080917.nc'
 liqcldoptics           = 'gammadist'
 liqopticsfile          = '$DIN_LOC_ROOT/atm/cam/physprops/F_nwvl200_mu20_lam50_res64_t298_c080428.nc'
 rad_climate            = 'P_Q:H2O', 'D_O2:O2', 'D_CO2:CO2', 'D_ozone:O3', 'D_N2O:N2O', 'D_CH4:CH4', 'D_CFC11:CFC11',
  'D_CFC12:CFC12', 'P_so4_a1:$DIN_LOC_ROOT/atm/cam/physprops/sulfate_rrtmg_c080918.nc',
  'P_pom_a1:$DIN_LOC_ROOT/atm/cam/physprops/ocpho_rrtmg_c101112.nc',
  'P_soa_a1:$DIN_LOC_ROOT/atm/cam/physprops/ocphi_rrtmg_c100508.nc',
  'P_bc_a1:$DIN_LOC_ROOT/atm/cam/physprops/bcpho_rrtmg_c100508.nc',
  'P_dst_a1:$DIN_LOC_ROOT/atm/cam/physprops/dust4_rrtmg_c090521.nc',
  'P_ncl_a1:$DIN_LOC_ROOT/atm/cam/physprops/ssam_rrtmg_c100508.nc',
  'P_so4_a2:$DIN_LOC_ROOT/atm/cam/physprops/sulfate_rrtmg_c080918.nc',
  'P_soa_a2:$DIN_LOC_ROOT/atm/cam/physprops/ocphi_rrtmg_c100508.nc',
  'P_ncl_a2:$DIN_LOC_ROOT/atm/cam/physprops/ssam_rrtmg_c100508.nc',
  'P_dst_a3:$DIN_LOC_ROOT/atm/cam/physprops/dust4_rrtmg_c090521.nc',
  'P_ncl_a3:$DIN_LOC_ROOT/atm/cam/physprops/ssam_rrtmg_c100508.nc',
  'P_so4_a3:$DIN_LOC_ROOT/atm/cam/physprops/sulfate_rrtmg_c080918.nc'
/
&solar_inparm
 solar_const            = -1400.00

 

[eaton]

What model version are you using?What is the error?Why would you expect a solar constand of -1400. to work? 

 

[amatcaos@caos_iisc_ernet_in]

 HelloI am using E1850C5CN compset and the resolution is f19_g16. Error in ccsm.log.130613-222511-photo_inti: solar_data file needs to contain irradiance spectrumENDRUN:photo_inti: ERROR -- solar irradiance spectrum is missingphoto_inti: solar_data file needs to contain irradiance spectrumENDRUN:photo_inti: ERROR -- solar irradiance spectrum is missingphoto_inti: solar_data file needs to contain irradiance spectrumENDRUN:photo_inti: ERROR -- solar irradiance spectrum is missingphoto_inti: solar_data file needs to contain irradiance spectrumENDRUN:photo_inti: ERROR -- solar irradiance spectrum is missingphoto_inti: solar_data file needs to contain irradiance spectrumENDRUN:photo_inti: ERROR -- solar irradiance spectrum is missing[cli_69]: aborting job:application called MPI_Abort(MPI_COMM_WORLD, 1) - process 69[cli_70]: aborting job:application called MPI_Abort(MPI_COMM_WORLD, 1) - process 70[cli_71]: aborting job:application called MPI_Abort(MPI_COMM_WORLD, 1) - process 71[cli_67]: aborting job:application called MPI_Abort(MPI_COMM_WORLD, 1) - process 67[cli_68]: aborting job:application called MPI_Abort(MPI_COMM_WORLD, 1) - process 68photo_inti: solar_data file needs to contain irradiance spectrumENDRUN:photo_inti: ERROR -- solar irradiance spectrum is missing From solar_const = -1400.00, I mean that the solar constant is 1400W/m2. ThanksAngshuman

 

[eaton]

I did a simple test in cesm1_1_1 and was able to reproduce the error you observed when the solar_const variable is specified.  The cam5 physics package makes use of the prognostic modal aerosol chemistry package (trop_mam3) and it turns out that there is a photolysis reaction in this scheme which is why the spectral irradiance is required.  The solar data file is used by both the radiative heating rate calculations and the chemistry photolysis calculations to ensure consistency.  So to use a simple solar constant with the RRTMG radiation code it appears that it will be necessary to use a prescribed aerosol scheme which doesn't involve photolysis reactions.

 

[amatcaos@caos_iisc_ernet_in]

HiIt seems that I have to use the solar data file 'SOLAR_SPECTRAL_Lean_1610-2008_annual_c090324.nc' in my experiment because I want the photolysis reactions to get involved. So, can you please suggest me a way (or direct me to a person) to modify this solar data file. Basically I want to reduce the solar constant by some percent and perform an experiment. Now, in order to do that how I should modify the solar data file.Thanks  againAngshuman 

 

[eaton]

There is information about the solar data in the cam5 description available from the cam home page.
If you want to reduce the total irradiance by some percent then I assume you'd do this by multiplying all the spectral irradiances by the same factor.