WRF ARW User's Guide - MMM - UCAR

MODEL
ice flag (0)
&fdda
(for grid nudging)
for grid, obs and spectral nudging
grid_fdda (max_dom) 1 grid analysis nudging on (=0 off)
2 spectral analysis nudging option
gfdda_inname “wrffdda_d” defined name in real
gfdda_interval
(max_dom)
360 Time interval (min) between analysis
times
gfdda_end_h (max_dom) 6 Time (h) to stop nudging after start of
forecast
io_form_gfdda 2 analysis format (2 = netcdf)
fgdt (max_dom) 0 calculation frequency (in minutes) for
analysis nudging. 0 = every time step, and
this is recommended
fgdtzero 0 not active
1 nudging tendencies are set to zero in
between fdda calls
if_no_pbl_nudging_uv
(max_dom)
if_no_pbl_nudging_t
(max_dom)
if_no_pbl_nudging_q
(max_dom)
if_no_pbl_nudging_ph
(max_dom)
0 1= no nudging of u and v in the pbl; 0=
nudging in the pbl
0 1= no nudging of temp in the pbl; 0=
nudging in the pbl
0 1= no nudging of qvapor in the pbl; 0=
nudging in the pbl
0 1= no nudging of ph in the pbl; 0=
nudging in the pbl; only for spectral
nudging
if_zfac_uv (max_dom) 0 0= nudge u and v in all layers, 1= limit
nudging to levels above k_zfac_uv
k_zfac_uv 10 10=model level below which nudging is
switched off for u and v
if_zfac_t (max_dom) 0 0= nudge temp in all layers, 1= limit
nudging to levels above k_zfac_t
k_zfac_t 10 10=model level below which nudging is
switched off for temp
if_zfac_q (max_dom) 0 0= nudge qvapor in all layers, 1= limit
nudging to levels above k_zfac_q
k_zfac_q 10 10=model level below which nudging is
switched off for water qvapor
WRF-ARW V3: User’s Guide 5-44