The forecast model was changed with updates to the handling/advection of
tracers arrays, with the passive advection of Q now called every time step.
Turned back on Metop-A HIRS4 radiances.
Turned off Metop-A HIRS4 radiances dues to degraded data during engineering tests.
GSI analysis fix for the 11/26 failure : a bug in subroutine
sonde_ext in file read_prepbufr.f90 was found. The check to prevent array out of bounds
was in place but after printing an error message
the program was stopped. A fix was made to return to the calling routine instead of
stopping execution, which would allow the analysis to continue to run. With this code
change, raob level enhancement has been turned back on.
Turned off raob level enhancement (by changing “ext_sonde=true” to “ext_sonde=false”)
in the GSI analysis; this change fixed the failure of the ops and parallel 12z 11/26/2015 NAM analysis.
||W.S. Whu, Rogers
Turned on Himawari satellite wind data
New observations types added to GSI analysis:
- New satelllite winds
- MTSAT2 IMAGER WVct AMVs (JMA)
- 254 54 M-7 IMAGER WVct AMVs
- M-10 IMAGER WVct AMVs
- NOAA -15 AVHRR IR AMVs
- NOAA -18 AVHRR IR AMVs
- NOAA -19 AVHRR IR AMVs
- METOP-A AVHRR IR AMVs
- METOP-B AVHRR IR AMVs
- New GPS Radio Occultation Data
- METOP-B 3 (subtype)
- New Satellite radiance data
- M10 Seviri
- metop-b hirs4 (moni), amsua, mhs, iasi
- npp atms, cris
- f17 ssmis
A simple filter is applied to the vertical velocity used in the
vertical advection of tracers. This is to address issues associated with
unphysical moisture profiles which, in addition to unphysicality, may also
be problematic elsewhere within the model (e.g. radiation). It is worth
oting that the issue is generally uncommon, but has caused stability
problems in model (notably, hte prod NAM failures at 18z 9/29/15 and 06z 10/1/15
A change was made to the Noah LSM to consider the effect of frozen soil on plant
transpiration and soil evaporation, specifically:
The above changes are based on the assumption that ice is not available to plants and can not be evaporated.
- Change SMCREF to SMCREF = SMCREF + ICE or SMCREF = SMCREF + (SMC(1)-SH2O(1))
- Change GX = (SMC (1) - SMCWLT) / (SMCREF - SMCWLT) to GX = (SH2O (1) - SMCWLT) / (SMCREF - SMCWLT)
- Change SRATIO = (SMC(1) - SMCDRY) / (SMCMAX - SMCDRY) to SRATIO = (SH2O(1) - SMCDRY) / (SMCMAX - SMCDRY)
- Change (a) and (b) will increase canopy resistance and reduce plant transpiration
- Change (c) will reduce direct evaporation from soil.
||Rogers, W.-S. Whu, S. Liu
To create the input observation files, the prepbufr file from the next NDAS valid at T+3 h
is merged with the tm03+tm00 prepbufr file that now being used. The same is being done
with all the radiances and satwnd data.
||Ferrier, H-M. Lin
Changes to the radiation / microphysics:
- The cloud droplet effective radius is calculated assuming a monodisperse droplet distribution.
It is also not allowed to be less than minimum a value of 5 microns, which is reached when cloud water
contents are less than 0.1045 g m^-3. The droplet effective radius is no longer forced to be between
10 and 15 microns. The change is anticipated to reduce incoming surface shortwave fluxes under liquid
clouds and reduce daytime 2 m warm biases.
- The assumed cloud droplet number concentration within radiation is no longer assumed
to vary with temperature. Instead it is assumed to be a fixed value of 200 cm^-3, the same as what is
assumed in the FA microphysics.
Changed code so that Rhgrd (RH threshold for onset of condensation) is set in the configure file so it can vary
for different domains; current settings are RHgrd=0.98 for the 12 km parent domain, RHgrd=1.0 for the 3 km nests
Includes a cloud water mixing ratio threshold for the autoconversion of cloud water to rain.
||W.-S. Whu, S. Liu
First run with 4Denvar version of regional GSI, constructed as follows:
- NDAS changed to run a single 9-h forecast from t-6 h (using the NDASX
tm06 initial conditions)
- TM00 analysis reads 3-h, 6-h, and 9-h output files from the tm06 9-h
forecast (satellite bias corrections from NDASX)
- TM00 analysis uses global EnKF sigma files from the same 3 valid times
as the 3/6/9-h output from the tm06 forecast
- Input observations are created by merging the ops NAM tm00 observations
and the ops NDAS tm03 observation files
- Same forecast model as used in NAMX