The FIM Global Model
2-m Temperature
Precipitable Water/500hPa Height
250hPa Wind
Total 5-day Accumulated Precip
A unique combination of 3 numerical design features
- Icosahedral horizontal grid, mostly hexagons except for 12 pentagons ("I" in FIM)
- Isentropic-sigma hybrid vertical coordinate, adaptive, concentrates around frontal zones,
tropopause, similar to RUC model ("F" for Flow-following in FIM)
- Finite-volume horizontal transport (Also under "F", for "finite-volume" in FIM)
News Items
-
24 Aug 2012 - Update:
A yet newer version of FIM with 4th-order diffusion is
now running at 15km and 30km, showing much better
tropical cyclone intensity.
Click
here for real-time products from new
15km FIM with 4th-order diffusion.
-
21 Aug 2012 - Update:
New version of FIM running since April 2012 with 2nd-order momentum diffusion, ozone physics,
improved interpolation near poles. This version is being used
for summer-fall 2012 FIM runs for the NOAA Hurricane Forecast Improvement
Project, including a
15km version
run every 6h. FIM-15km (FIM9) tropical cyclone (hurricane) track forecasts
are available
here
-
14 Dec 2011 - Update:
FIM update today: Upgrade to GFS physics suite: 1) decrease in
vertical diffusion in stratosphere (above 200 hPa), 2) change
to thermal roughness length. These changes were implemented
in the operational GFS in April 2011.
-
21 Nov 2011 - Update:
A new version of FIM with significantly improved performance
and faster runtime was implemented at 00z 16 Nov 2011 for
the FIM real-time runs. Information and verification from a 5-month
retrospective test period is available
here
-
22 Aug 2011 - Update:
Hurricane season: FIMY (EnKF init conds) is being used
as experimental guidance at the Natl. Hurricane Center
as part of the NOAA Hurricane Forecast Improvement Project (HFIP).
A 10-member FIM ensemble and a 20-member FIM-GFS multi-model
ensemble are also being run as part of HFIP.
Experimental track guidance available at
http://ruc.noaa.gov/tracks
and at
http://www.esrl.noaa.gov/psd/forecasts/gfsenkf/fimens
.
-
16 May 2011 -
All versions of FIM were updated for the 12z run today
to allow solar radiation calculations to vary with the
valid date during the simulation (previously was fixed
to the earth orbit/tilt corresponding to the initial date of the forecast simulation).
-
4 Apr 2011 -
All versions of FIM were updated for the 12z run today
to correct a coding error in the horizontal
flux-corrected transport.
The effects of this fix are significant, resulting in
less diffusion overall and in somewhat tighter and
stronger tropical cyclones.
-
17 Jan 2011 -
All versions of FIM updated to correct CO2 value.
They had inadvertently been using zero CO2 since 13 Sept 2010.
-
16 Nov 2010 -
The
30km FIMZ
is now running with a correction to the shallow
convection scheme from the "new" GFS physics,
ensuring that there are no negative fluxes and
excessively large heating rates. This problem has
been an issue for all FIM runs since 14 Sept (see next news item).
-
14 Sept 2010 -
All FIM runs are now updated to "new" (2010) GFS physics suite,
including
the vanilla 30km
FIM
run with GSI initial conditions.
-
1 Sept 2010
- Update:
1.
15km FIM
added
(using new GFS physics
and EnKF initial conditions) - run daily at 00z.
2. FIMZ started using fully updated new GFS physics on Wed 25 Aug -
FIMZ real-time products over the western Atlantic domain.
-
9 July 2010
- New GFS physical parameterization package
to be implemented in operational GFS on 29 July 2010
is now also running in the FIMZ version.
FIMZ real-time products over the western Atlantic domain.
-
27 June 2010 - For best FIM hurricane/tropical cyclone
forecasts
(per 2009 results), use FIMY with EnKF-derived initial conditions
(mean EnKF from Jeff Whitaker's GFS T254 ensemble). --
FIMY real-time products over the western Atlantic domain.
-
13 May 2010 - FIM-Chem-Ash now includes washout
from precipitation/cloud processes.
As of 11 May, the FIM-Chem-Ash model started to include scavenging of volcanic
ash by large-scale precipitation processes. This results of much more realistic
areal coverage in the real-time FIM-Chem-Ash forecasts. In addition.
The real-time forecasts now include ash products for 3 different layers:
sfc-20km, 20-35km, 35-50km. These are available under
the FIMX real-time products.
-
4 May 2010 - FIM-Chem-Ash now producing experimental
real-time volcanic ash forecasts.
An inline chemistry of the FIM global model is now running in real-time
with 17 aerosol and gas-phase tracer concentrations, including 4 size bins of volcanic ash.
The FIM-Chem-Ash real-time runs are now in the FIMX slot.
Other key information:
- 30-km resolution
- 14 aerosol concentration and
3 gas-phase prognostic variables are cycled and have
been since 14 April (start of explosive eruption of Eyjafjallajokull)
- Forecasts are run out to 5-day duration for each 00z initial time,
and a shorter 12-h forecast is run at 12z each day to maintain the
aerosol/ash cycling.
- Forecast products are available at
http://fim.noaa.gov/FIMscp/Welcome.cgi?dsKey=fimx
- GFS analyses are used for atmospheric initial conditions in the
FIM-Chem-Ash runs, combined with cycled 3-d aerosol initial fields
from previous 12-h forecast
- These runs are experimental and still under development --
expect further changes. They are not official guidance.
- Only eruption data from Eyjafjallajokull is currently included.
-
12 Mar 2010
FIM (primary) now using coordinate pressure smoothing (50 m/s- diffusion velocity) -- a
"promotion" of the 4Feb-11Mar FIMX. As of 12 Mar, FIMX (experimental)
now is distinguished from FIM only in that
it uses still smoother horizontal hybrid (isentropic-sigma) surfaces (125 m/s-diffusion velocity).
FIMY (EnKF initial conditions) continues to use the same model configuration
as the FIM-control model, so comparisons of FIM and FIMY are solely due to
EnKF initial conditions vs. GSI initial conditions.
-
4 Feb 2010
New FIM version in parallel FIMX slot for real-time runs - now using revised vertical coordinate
with significant reduction in noise via smoothing of coordinate surface pressure for hybrid theta-sigma.
-
27 Nov 2009
- 3 FIM variations now running at 30km
- FIM - GSI-GFS initial conditions - hybrid isentropic-sigma vertical coordinate
- FIMX - GSI-GFS initial conditions - hybrid sigma-pressure vertical coordinate
- FIMY - EnKF initial conditions - hybrid isentropic-sigma vertical coordinate
Real-time products
for each version and FIM-FIMX differences (vertical coordinate) and
FIM-FIMY (initial conditions)
14 Oct 2009 - FIM runs at TACC (15km, 10km) are discontinued
- end of available TACC computing resources and approximate end of Atlantic hurricane season
-
17 August 2009
Much progress in FIM development and testing -
FIM is now running at
10km resolution
once daily at the TACC supercomputer.
Also, an ensemble Kalman filter global assimilation cycle is now being used to initialize
both 15km runs and 10km FIM forecasts at TACC. Viewers can compare
FIM-15km forecasts
initialized by GFS
vs.
those initialized by EnKF.
All of these TACC 10km/15km FIM runs
include the changes reported for GSD FIM runs on 26 July (bullet below).
-
26 July 2009
FIM-30km-GSD runs now include random variations in cloud-top in the convective parameterization,
a further correction to initial soil moisture, and a restructuring of the reference potential
temperatures in the upper stratosphere to lower mesosphere to improve model stability. (r671)
These changes will be added to TACC FIM runs in the near future, along with others.
-
24 July 2009
Products from
new ensemble-Kalman-filter initialized
15km FIM runs
(be sure to click on FIM-ENKF on left)
are now available to compare with
counterpart
15km FIM runs initialized with GFS analysis
. Both of these are run on the NSF TACC Ranger supercomputer.
This is the first time that the FIM model has been run by any
options other than the GFS analysis, and these FIM-EnKF runs
will be compared with the FIM-GFS-analysis runs as part of
NOAA's HFIP.
-
10 July 2009
15km FIM runs
have returned, initialized once daily (00z),
NOAA-NSF agreement renewed for use of TACC for
NOAA Hurricane Forecast Improvement Project (HFIP) (previous
agreement expired in March09).
Also, changes coming soon on cumulus parameterization cloud top
and higher-resolution topography.
-
20 Mar 2009
Correction to initialization and evolution
of liquid (and frozen) soil moisture in GFS/Noah LSM currently
used in FIM. (r577)
-
26 Feb 2009
Correction to land-use table used
for 13-class land-use in GFS/Noah LSM
in FIM. (r559)
-
30 Dec 2008
Introduced momentum damping for winds > 100 m/s above 5 hPa,
found to be necessary after seasonal changes began to
develop polar-night jets. (r487)
-
25 Nov 2008
Snow accumulation at surface added, less noise (vertical adjustment) (FIM r456)
-
17 Nov 2008
Correction to atmospheric radiation time error
(significantly improves 12z init FIM forecasts).
Shallow convection added on 10 Nov.
-
5 Nov 2008
64-level version introduced with pressure-top at 0.1 hPa
(previous - 50-level with ptop at 20 hPa).
Also added accurate use of sea-ice fraction.
(FIM r392).
-
17 Oct 2008
Important FIM changes for GSD-FIM30(G8) and TACC-FIM15(G9) runs as of today:
Fix to initial height problem, now using initial cloud/condensate
fields from GFS, physics called now every 3 min (less frequently
but matching GFS), run time reduced 20-25%. (FIM r383).
-
7-9 Oct 2008
Isentropic-Hybrid Modeling Workshop - NOAA/ESRL
-
22 Sept 2008
15km FIM global model runs out to 10-day duration since 28 Aug, output every 3h -
Real-time products here.
-
Status here.
Twice daily forecasts run on TACC (Texas Area Computing Center) supercomputer as part of NOAA-TACC demonstration for improved hurricane forecasts.
-
30 Aug 2008
Two key problems fixed for FIM over last 9 days,
one concerning interpolation of GFS initial conditions to the FIM grid
(fixed 22 Aug),
and one concerning initializing soil moisture (fixed 28 Aug).
Both of these bugs were significant. (FIM r317)
Also, regional output is now available for the
western Pacific .
.
-
17 July 2008
Regional products added for
Arctic
and
western N. Atlantic
.
Also, sensible and latent heat flux products
added for all global and regional plot domains.
-
2 July 2008
Regional products now available for
Africa
and
CONUS
.
Other regions under development.
-
2 July 2008
Output redesign for FIM model for isobaric grids on icosahedral grid
-
4 June 2008
Error in land-surface specification corrected.
- Drying trend in forecasts removed
- Improved overall forecast skill
-
8 May 2008
Twice-daily forecasts now out to 168 h (7 days) since late April.
-
17 April 2008
Virtual temperature effect added to calculation of pressure gradient.
Prognostic temperature variable is now virtual potential temperature.
Average global precipitation and mean zonal wind at jet level increased by about 10% in
spring 2008 cases. Change made on 15 April.
-
8 April 2008
Real-data FIM forecasts started in Feb 2008. Graphics
here.
- GFS initial conditions, interpolated from GFS spectral data for analysis
- 30km horizontal resolution for FIM runs
- 50 vertical levels (changed to 64 levels with ptop = 0.1 hPa - 5 Nov 2008)
- Use of GFS physical parameterizations (other options to be added
including WRF physics options and WRF-chem as a further option)