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A question regarding the values of the Shortwave clear-sky downward flux (FDSC)

B

bethproedrou@gmail_com

Member
Dear all,I have a question regarding the outputed shortwave clear-sky downward flux (FDSC). The entry in the simulation output file is:FDSC        Size:       72x46x67x24Dimensions: lon,lat,ilev,timeDatatype:   singleAttributes:mdims     = 2units     = 'W/m2'long_name = 'Shortwave clear-sky downward flux' which is reasonable. However when I open the parameter I get values  1.14e6. However since the total solar irradiance at the top of the model is 1366.96 < So < 1368.60, such a number is not reasonable. Could someone explain to me what exactly does this parameter output? Thank you in advance,Beth
 
mmills

mmills

CSEG and Liaisons
Staff member
We generally look at these outputs: 3954 FSNTC                            W/m2                1 A  Clearsky net solar flux at top of model 3955 FSNSC                            W/m2                1 A  Clearsky net solar flux at surface 3956 FSDSC                            W/m2                1 A  Clearsky downwelling solar flux at surface 3957 FSDS                             W/m2                1 A  Downwelling solar flux at surfaceand similar 2D fields that give fluxes at the surface, at the top of model, at the top of atmosphere, or at a specific level in the atmosphere.  FDS and FDSC give fluxes at each level. Which levels are outputting the anomalously high values?
 
mmills

mmills

CSEG and Liaisons
Staff member
We generally look at these outputs: 3954 FSNTC                            W/m2                1 A  Clearsky net solar flux at top of model 3955 FSNSC                            W/m2                1 A  Clearsky net solar flux at surface 3956 FSDSC                            W/m2                1 A  Clearsky downwelling solar flux at surface 3957 FSDS                             W/m2                1 A  Downwelling solar flux at surfaceand similar 2D fields that give fluxes at the surface, at the top of model, at the top of atmosphere, or at a specific level in the atmosphere.  FDS and FDSC give fluxes at each level. Which levels are outputting the anomalously high values?
 
B

bethproedrou@gmail_com

Member
The values are 1000 time larger than they should be from what I have seen. Does someone have an explanation for this? If noone knows it would also be something that I would like to know. Beth
 
B

bethproedrou@gmail_com

Member
The values are 1000 time larger than they should be from what I have seen. Does someone have an explanation for this? If noone knows it would also be something that I would like to know. Beth
 
mmills

mmills

CSEG and Liaisons
Staff member
The code where it is calculated is in:models/atm/cam/src/physics/cam/radsw.F90 !  these outfld calls don't work for spmd only outfield in scm mode (nonspmd)   if (single_column.and.scm_crm_mode) then    ! Following outputs added for CRM      call ExpDayNite(fus,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call ExpDayNite(fds,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call ExpDayNite(fusc,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call ExpDayNite(fdsc,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call outfld('FUS     ',fus * 1.e-3_r8 ,pcols,lchnk)      call outfld('FDS     ',fds * 1.e-3_r8 ,pcols,lchnk)      call outfld('FUSC    ',fusc,pcols,lchnk)      call outfld('FDSC    ',fdsc,pcols,lchnk)   endif I notice that FUS and FDS are multiplied by 1.e-3, but FUSC and FDSC are not. So it looks to me like you have found a bug, and you should treat the units on FUSC and FDSC as mW/m2 instead of W/m2. I will report the bug!
 
mmills

mmills

CSEG and Liaisons
Staff member
The code where it is calculated is in:models/atm/cam/src/physics/cam/radsw.F90 !  these outfld calls don't work for spmd only outfield in scm mode (nonspmd)   if (single_column.and.scm_crm_mode) then    ! Following outputs added for CRM      call ExpDayNite(fus,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call ExpDayNite(fds,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call ExpDayNite(fusc,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call ExpDayNite(fdsc,Nday, IdxDay, Nnite, IdxNite, 1, pcols, 1, pverp)      call outfld('FUS     ',fus * 1.e-3_r8 ,pcols,lchnk)      call outfld('FDS     ',fds * 1.e-3_r8 ,pcols,lchnk)      call outfld('FUSC    ',fusc,pcols,lchnk)      call outfld('FDSC    ',fdsc,pcols,lchnk)   endif I notice that FUS and FDS are multiplied by 1.e-3, but FUSC and FDSC are not. So it looks to me like you have found a bug, and you should treat the units on FUSC and FDSC as mW/m2 instead of W/m2. I will report the bug!
 
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