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precipitable water assimilation

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lucarovai2

New member
Hello everyone,
it's the first time I use this forum. I have a problem (maybe) with the assimilation of gpspw. I tried to run the model (wrf vers.4) from 00 UTC to 12 UTC (CTRL race). So at 6 UTC I extracted on 8 points (dislocated in Italy) the values of pwatclm (atmos column Precipitable water [kg / m ^ 2]) and then I made them assimilate from the model. The comparison between the wrf outputs (run of the model with assimilation at 6 UTC and stroke of the CTRL model at 6 UTC), contrary to my wait tells me that the difference is not 0. Among other things at 6 UTC I also applied the filter to eliminate the spin-up. Can someone tell me why I get a difference?
Thanks, Luca
 
Hi, Luca
I have meet a same problem when I trying to run WRFDA-4DVAR. I have done them many times, but failed. How did you solve it? If possible, i hope you can help me! the related decoments are as fallow:
(1) namelist.input:
&wrfvar1
var4d=true,
var4d_lbc=false,
var4d_bin=3600,
var4d_bin_rain=21600,
print_detail_outerloop=false,
print_detail_grad=false,
/
&wrfvar2
/
&wrfvar3
ob_format=2,
/
&wrfvar4
use_synopobs=false,
use_shipsobs=false,
use_metarobs=false,
use_soundobs=false,
use_pilotobs=false,
use_airepobs=false,
use_geoamvobs=false,
use_polaramvobs=false,
use_bogusobs=false,
use_buoyobs=false,
use_profilerobs=false,
use_satemobs=false,
use_gpspwobs=false,
use_gpsrefobs=false,
use_qscatobs=false,
use_rainobs=true,
thin_rainobs=true,
thin_mesh_conv=30.,
/
&wrfvar5
check_max_iv=false,
/
&wrfvar6
max_ext_its=1,
ntmax=100,
orthonorm_gradient=true,
/
&wrfvar7
cv_options=3,
je_factor=1.0,
/
&wrfvar8
/
&wrfvar9
/
&wrfvar10
test_transforms=false,
test_gradient=false,
/
&wrfvar11
cv_options_hum=1,
check_rh=0,
sfc_assi_options=1,
calculate_cg_cost_fn=true,
/
&wrfvar12
/
&wrfvar13
/
&wrfvar14
/
&wrfvar15
/
&wrfvar16
/
&wrfvar17
/
&wrfvar18
analysis_date="2013-10-06_06:00:00.0000",
/
&wrfvar19
/
&wrfvar20
/
&wrfvar21
time_window_min="2013-10-06_06:00:00.0000",
/
&wrfvar22
time_window_max="2013-10-06_12:00:00.0000",
/
&time_control
run_hours=6,
start_year=2013,
start_month=10,
start_day=06,
start_hour=06,
end_year=2013,
end_month=10,
end_day=06,
end_hour=12,
interval_seconds=21600,
debug_level=0,
/
&domains
time_step=180,
e_we=60,
e_sn=60,
e_vert=31,
p_top_requested=5000,
interp_type=1,
t_extrap_type=1,
dx=30000,
dy=30000,
smooth_option=0,
nproc_x=0,
hypsometric_opt=2,
/
&fdda
/
&dfi_control
/
&tc
/
&physics
mp_physics=3,
ra_lw_physics=1,
ra_sw_physics=1,
radt=30,
sf_sfclay_physics=1,
sf_surface_physics=2,
bl_pbl_physics=1,
cu_physics=1,
cudt=5,
num_soil_layers=4,
mp_zero_out=2,
co2tf=0,
/
&scm
/
&dynamics
w_damping=0,
diff_opt=1,
km_opt=4,
dampcoef=0.2,
time_step_sound=4,
base_temp=290.0,
use_baseparam_fr_nml=true,
/
&bdy_control
specified=true,
real_data_init_type=3,
/
&grib2
/
&namelist_quilt
/
&perturbation
trajectory_io=true,
enable_identity=false,
jcdfi_use=false,
jcdfi_diag=1,
jcdfi_penalty=1000.0,
/
(2) My fortran codes, which used to transfor precipitation data into readable docement by the WRFDA.
program precip
implicit none
integer :: N,i
real, dimension(10605) :: LAT
real, dimension(10605) :: LON
real, dimension(1) :: MISSING_R
real, dimension(10605) :: RAIN
character(100) :: DATE
character(100) :: NAME
character(100) :: fileDir,fileName,fileSuffix
N=10605
MISSING_R=-888888.
DATE='2013-10-06_11:59:59'
NAME='ob.rain.2013100612.06h'
!fileDir = "/mnt/d/Experiment20190301/obsproc"
!fileName = "obsdata"
!fileSuffix = ".txt"
open(100, file = '/mnt/d/experiment2/wrfda/writerain/trmm2013106.txt')
!open(100, file = adjustl(trim(fileDir))//&
! adjustl(trim(fileName))//adjustl(trim(fileSuffix)))
open(999, file = NAME,status='new',access='append')
write(999, fmt = '((A,I7),A)', advance = 'no') "TOTAL =", N,","
write(999, fmt = '((A, F8.0), A)') "MISS. =", MISSING_R,","
write(999, fmt = '(A)') &
"INFO = PLATFORM, DATE, LEVELS, LATITUDE, LONGITUDE, ELEVATION, ID."
write(999, fmt = '(A)' ) &
"EACH = HEIGHT, RAINFALL DATA, QC, ERROR"
write(999, fmt = '(A)') &
"#------------------------------------------------------------------------------#"
do i = 1, N
read(100,*) LON(i), LAT(i), RAIN(i)
write(999, fmt = '(A12, 1X, A19, 1X, I6, 2(F12.3,2X), F12.1, 1X, A5)') &
"FM-129 RAIN ", DATE, 1, LAT(i), LON(i),MISSING_R, "xxxxx"
write(999, fmt = '(F12.3, F12.3, I4, F12.3)') &
MISSING_R, RAIN(i), 88, 2.000
end do
close(unit=100)
end
 
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