Weird pixilated skin temperatures when using sf_ocean_physics = 1

[stormchasegenie]

Greetings,

I am able to stably run WRF version 4.1.3 for a full year with:

sf_ocean_physics = 1,
isftcflx = 1,
oml_hml0 = 50
oml_gamma = 0.14.

I can complete a full year simulation. However, I'm noticing strange granular artifacts in the skin temperature and surface longwave fluxes. I have sst_update = 1 and

io_form_auxinput4 turned on. What could be happening here?

See attached figures and namelist.

-Stefan Rahimi, UCLA

Namelist:

&time_control
run_days = 70
run_hours = 0,
run_minutes = 0,
run_seconds = 0,
start_year = 2010, 2009, 2009, 2009
start_month = 07, 08, 08, 08,
start_day = 23, 01, 01, 01,
start_hour = 00, 00, 00, 00,
end_year = 2010, 2010, 2010, 2010
end_month = 10, 10, 10, 10,
end_day = 01, 01, 01, 01,
end_hour = 00, 00, 00, 00,
interval_seconds = 21600
input_from_file = .true.,.true.,.true.,.true.,
history_interval = 360, 360, 360, 360,
frames_per_outfile = 1, 1, 1, 1,
restart = .true.,
restart_interval = 28800,

write_hist_at_0h_rst = .true.
adjust_output_times = .true.,
override_restart_timers = .true.

io_form_history = 2
io_form_restart = 2
io_form_input = 2
io_form_boundary = 2
a
io_form_auxinput2 = 2
a
auxinput4_inname = "wrflowinp_d<domain>",
auxinput4_interval_m = 360, 360, 360, 360,

auxhist7_outname = "auxhist_d<domain>_<date>",
auxhist7_interval = 60,
frames_per_auxhist7 = 1, 1,
io_form_auxhist7 = 2

debug_level = 0,
/

&domains
time_step = 120,
use_adaptive_time_step = .ture.
step_to_output_time = .true.
target_cfl = 1.2, 1.2
max_step_increase_pct = 5, 51
adaptation_domain = 1
starting_time_step = -1, -1
max_time_step = -1, -1
min_time_step = -1, -1

max_dom = 1,

parent_id = 1, 1, 2, 2,
parent_grid_ratio = 3, 3, 3,
i_parent_start = 70,
j_parent_start = 45,
s_we = 1, 1,
s_sn = 1, 1,
e_we = 805,
e_sn = 532,
sfcp_to_sfcp = .true.,
e_vert = 40, 40, 40, 40,
p_top_requested = 5000,
num_metgrid_levels = 38,
num_metgrid_soil_levels = 4,
dx = 8333.333, 3000, 3000,
dy = 8333.333, 3000, 3000,
grid_id = 2, 3, 4,
parent_time_step_ratio = 5, 3, 3,

feedback = 0,
smooth_option = 0
smooth_cg_topo = .true.,
/

&physics

!New
mp_zero_out = 2,
mp_zero_out_thresh = 1.e-8
slope_rad = 1,
topo_shading = 1,
shadlen = 1,
sf_ocean_physics = 1,
isftcflx = 1,
oml_hml0 = 50
oml_gamma = 0.14

mp_physics = 51, 51, 51, 51,
cu_physics = 16, 16, 0, 0,
ra_lw_physics = 4, 4, 4, 4,
ra_sw_physics = 4, 4, 4, 4,
bl_pbl_physics = 1, 1, 1, 1,
sf_sfclay_physics = 1, 1, 1, 1,
sf_surface_physics = 4, 4, 4, 4,
radt = 5, 8, 3, 3,
bldt = 0, 0, 0, 0,
cudt = 0, 0, 0, 0,
icloud = 1,
num_land_cat = 21,
sf_urban_physics = 0, 0, 0, 0,
sst_update = 1,
sst_skin = 1,

sf_lake_physics = 1, 1, 1, 1,
use_lakedepth = 1, 1, 1, 1,

co2_ppmv = 313.14944
ch4_ppbv = 1202.4291

/

&noah_mp
opt_run = 1,
opt_sfc = 1,
opt_rsf = 1,
opt_snf = 1,
opt_rad = 1
/

&fdda
grid_fdda = 0
gfdda_inname = "wrffdda_d<domain>"
gfdda_interval_m = 360,
gfdda_end_h = 48000000,
io_form_gfdda = 2
fgdt = 0,
if_no_pbl_nudging_uv = 1
if_no_pbl_nudging_t = 1
if_no_pbl_nudging_q = 1
if_no_pbl_nudging_ph = 1
if_zfac_uv = 0
if_zfac_t = 0
if_zfac_q = 0
guv = 0.0003
gt = 0.0003
gq = 0.0
gph = 0.0003
xwavenum = 8
ywavenum = 5

/

&dynamics

!new
diff_6th_opt = 1, 0, 0, 0,

hybrid_opt = 0,
w_damping = 0,
diff_opt = 2, 2, 1, 1,
km_opt = 4, 4, 4, 4,
diff_6th_factor = 0.12, 0.12, 0.12, 0.12,
base_temp = 290.
damp_opt = 3,
zdamp = 10000., 10000., 10000.,
dampcoef = 0.2, 0.2, 0.2, 0.2,
khdif = 0, 0, 0, 0.,
kvdif = 0, 0, 0, 0.,
non_hydrostatic = .true., .true., .true., .true.,
moist_adv_opt = 1, 1, 1, 1,
scalar_adv_opt = 1, 1, 1, 1,
gwd_opt = 0,
/

&bdy_control
spec_bdy_width = 10,
relax_zone = 9,
specified = .true.
/

&grib2
/

&namelist_quilt
nio_tasks_per_group = 0,
nio_groups = 1,
/

 

[kwerner]

Hi,
Apologies for the long delay in response. Are you still experiencing this issue?

1) If you run without ocean physics turned on, do the stripes go away?
2) How long into the year-long simulation does this show up?

 

[stormchasegenie]

Greetings, and thank you for the reply. The problem does not present for my 14-month-long test experiments with ocean physics turned on. For (2), these features appear gradually and become prominent about 6 months into integration.

 

[Ming Chen]

sf_ocean_physics = 1 will turn on the slab ocean model, which is not a fully coupled ocean model and the ocean physics is simplified. For short-term simulation, this option may or may not help improve the simulation. For long-term climate simulation, however, it is recommended that this option should be off and high quality SST data should be used with sst_update = 1 .

 

[stormchasegenie]

Thank you for this. I guess this surprises me since you can run CESM2 with a slab ocean model for tens of years and not see these anomalies.