Instantaneous shortwave radiation variables are all zeros in wrfout, but accumulated fields are normal — why?

[845968376]

Hi everyone,


Recently I have been working on cloud–radiation related analysis using WRF output. I found that the following variables are present in my wrfout files:

• SWDNB, SWDNBC, SWDNT, SWDNTC, SWDOWN, SWNORM
• SWUPB, SWUPBC, SWUPT, SWUPTC

However, when I open the files with Panoply, I find that all of these instantaneous shortwave radiation fields are zero everywhere and at all times.
At the same time, their accumulated counterparts (for example, ACSWDNT, ACSWDNB, etc.) have non-zero values and look completely normal and reasonable.
So my questions are:

1. Why are these instantaneous shortwave radiation variables all zeros, even though the accumulated variables are valid?
2. If I want to output and analyze the true instantaneous shortwave radiation fields, what should I do?

For reference, here is the relevant part of my namelist.input:

&physics
mp_physics = 8, 8, 8,
ra_lw_physics = 4, 4, 4,
ra_sw_physics = 4, 4, 4,
radt = 9, 9, 9,
sf_sfclay_physics = 1, 1, 1,
sf_surface_physics = 2, 2, 2,
bl_pbl_physics = 1, 1, 1, ! YSU
bldt = 0, 0, 0,
cu_physics = 1, 1, 0,
cudt = 5, 5, 5,
isfflx = 1,
ifsnow = 0,
icloud = 1,
num_land_cat = 21,
sf_urban_physics = 0, 0, 0,
/

&dynamics
w_damping = 1,
diff_opt = 1, 1, 1,
km_opt = 4, 4, 4,
diff_6th_opt = 0, 0, 0,
diff_6th_factor = 0.12, 0.12, 0.12,
base_temp = 290.,
damp_opt = 3,
zdamp = 5000., 5000., 5000.,
dampcoef = 0.2, 0.2, 0.2,
khdif = 0, 0, 0,
kvdif = 0, 0, 0,
non_hydrostatic = .true., .true., .true.,
moist_adv_opt = 1, 1, 1,
epssm = 0.1, 0.3, 0.5,
scalar_adv_opt = 1, 1, 1,
etac = 0.1
/

&bdy_control
spec_bdy_width = 5,
spec_zone = 1,
relax_zone = 4,
specified = .true., .false., .false.,
nested = .false., .true., .true.,
/

&namelist_quilt
nio_tasks_per_group = 0,
nio_groups = 1,
/


Any suggestions or explanations would be greatly appreciated.


Thank you very much!