The NCAR Advanced Research WRF
(ARW)
• WRF in NCAR
• ARW Update and Plans
–Featuring recent hurricane successes
• The Nested Regional Climate Model
NCAR is sponsored by the National Science Foundation
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WRF Activities at NCAR
•
The Earth Sun Systems Laboratory
– Mesoscale and Microscale Meteorology Division
• ARW Developments and Maintenance
– Atmospheric Chemistry Division
• WRF-Chem
– High Altitude Observatory
• Gravity Waves
– Climate and Global Dynamics Division
• Nested Regional Climate Modeling
– The Institute for Integrative Multidisciplinary Studies
• Biogeosciences
•
Research Applications Laboratory Earth Observing Laboratory
• Wide range of operational and applied work
• Numerical Test Bed and Developmental Test Center
•
The Institute for the Study of Society and Environment
• Societal Impacts.
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Mesoscale & Microscale Meteorology
Division
Mission
To advance the understanding of meso- and microscale
aspects of weather and climate and apply this knowledge
to benefit society.
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MMM Research Theme
Mesoscale and Microscale Earth-System
Science Research aimed at:
• Improving our understanding of earth-system processes;
• Advancing the science of atmospheric prediction; and,
• Development and refinement of advanced, state-of-thescience research tools (including models, instrumentation
and data sets) and provision of these as a service to the
community.
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Our Research and Applications Matrix
Application
Facilities
Ideas flow both ways
Understanding
Dynamics &
Scale
Interactions Prediction
<48 h Weather
Prediction
WRF
Boundary
Atmos.
Precip.
Processes Chemistry Layer
Data
Assimilation
DA System
Air
Quality
Leading Edge
Science and
Publications
NRCM
Operations, Applications and Services
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Advanced Community Research Tools
• ARW Community Model
• Community Data Assimilation Techniques
–
–
–
–
3D Var
Ensemble Kalman Filter
ARW 4D Var
Radar Assimilation for Short Range Forecasting
• Nested Regional Climate Model
– New initiative based on ARW together with CGD, PMEL and
several universities.
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MMM Support for ARW
Understanding
Application
Facilities
Dynamics &
Scale
Interactions Prediction
<48 h Weather
Prediction
WRF
Boundary
Atmos.
Precip.
Processes Chemistry Layer
Data
Assimilation
DA System
Air
Quality
NRCM
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ARW as a Community Resource
•
•
•
•
>3200 Registered Downloads (50% international), supported by tutorials,
workshops and on-line help
Operational Community Support: AFWA, Korea, Beijing, India, China,
Taiwan, UW
Real Time Predictions: AMPS, Hurricanes
After an initial adjustment period there is now widespread praise from the
community:
– “The documentation was very helpful, concise and lucid, and the support from
"WRFHelp" was excellent”
– “The WRF software infrastructure was used as the driver layer of the GRAPES
model. The user interface is well defined and it is very easy to understand”
– “WRF is an example of how software organization can vastly reduce the
complexity of programming and maintaining not just the model itself, but up/downstream applications as well”
– “The entire WRF development team should be congratulated on bringing a flexible,
portable, and high performance NWP system to the meteorological community in
such little time”
– ..... See www.mmm.ucar.edu/wrf/WG2/wsf_testimonials.htm
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Highlights from 2005 User’s
Workshop
• Expanded capabilities for air-quality and
chemistry applications in WRF-Chem
(Grell, FSL)
• WRF regional climate applications
(Leung et al., PNNL)
• Global and plantetary version of WRF
(Richardson et al., Cal Tech)
Comparison of 36 h WRF-Chem 27 km forecasts
with AIRNOW daily 8-h max O3
Regional Climate
Daily mean precip
10/1/90-3/31/91
Rain Gage Data
Mars - surface temperature
30 km WRF
6 km WRF
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WRF Var Real Time Applications
AFWA 15km (e.g. SW Asia):
AMPS 30km:
Indian NCMRWF 30km:
Korean 10km:
Taiwanese CAA 135/45/15km:
Korean T213/T426:
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Chemistry, Aerosols, and Dynamics
WRF-Chem, a coupled meteorology and
multi-phase chemistry model
• Implemented aqueous chemistry into WRF model
(UTLS initiative) Æ
• Led an intercomparison of convective-cloud
chemistry models
Long-term goal: Generalize how deep convection
affects chemical species
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ARW Hurricane Forecasts
• 2-way nested, vortex tracking grid at 4km resolution,
explicit convection
• 12 km fixed grid nested into GFS, parameterized
convection
• Initial conditions either GFS or GFDL
• Run for last four years for Hurricanes threatening
landfall on the USA
• Incorporated into Los Alamos impacts prediction system
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2005 Intensity Predictions
45
SHF5
40
OFCL
35
Error (kt)
30
25
20
ARW 4 km Grid
2
DSHP
GFDL
19
FSSE
28
NWRF
31
35
NCHG
35
15
10
5
35
0
0
12
24
36
48
60
72
84
96
Forecast Tim e
Numbers indicate number of forecasts used and the red arrow indicates the NCAR WRF model. The
forecast techniques are: SHF5 statistical, OFCL, the final NHC forecast, DSHP statistical, GFDL the
GFDL Hurricane Model, FSSE the Florida State Super Ensemble of a number of models from various
centers, NWRF is the NCAR WRF Hurricane Model, NCHG is to predict no change of intensity (an
indicator of a no skill forecast).
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2005 Intensity Predictions
40
SHF5
35
OFCL
ARW 12 km Grid
DSHP
30
Error (kt)
25
GFDL
FSSE
28
31
NW12
20
NCHG
9
16
23
34
34
15
10
5
34
0
0
12
24
36
48
60
72
84
96
108
120
Forecast Tim e
Numbers indicate number of forecasts used and the red arrow indicates the NCAR WRF model. The
forecast techniques are: SHF5 statistical, OFCL, the final NHC forecast, DSHP statistical, GFDL the
GFDL Hurricane Model, FSSE the Florida State Super Ensemble of a number of models from various
centers, NWRF is the NCAR WRF Hurricane Model, NCHG is to predict no change of intensity (an
indicator of a no skill forecast).
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2005 Track Predictions
700
ARW 12 km
CLP5
OFCL
600
NW12
AVNO
Error (nm)
500
400
GFDL
NGPS
UKM
300
FSSE
200
100
0
0
12
24
36
48
60
72
84
96
108
120
Forecast Tim e
The forecast techniques are: CLP5 is a climatology and persistence forecast; OFCL is the final NHC
forecast; NWRF is the NCAR WRF Hurricane Model; AVNO is the NCEP Aviation Model, GFDL is
the GFDL Hurricane Model, NGPS is the Navy Global Model; UKM is the UK Met Office Global
Model; FSSE the Florida State Super Ensemble of a number of models from various centers.
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ARW Forecasts of Katrina Landfall
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48 hour Forecast, Hurricane Frances
10-m Wind; 48 h Fcst valid 00 UTC 5 Sept.
HRD Wind Analysis 2230 UTC 4 Sept.
Max Wind
100-110 kt
35
Official
Forecast
issued 03
UTC 3 Sept.
Max Wind
90 knots
based on
2044 drop
35
35
~35 kt
~100 kt
ARW 48-h Forecast 10 m
wind
NOAA/HRD 10-m HWind
Analysis
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Frances Wind Profiles
All profiles between 18 UTC 4 Sept. and 00 UTC 5
Sept. (42-48 h forecast with 4-km WRF)
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Precipitation Features in Frances
17 UTC 3 Sept (17 h fcst)
06 UTC 4 Sept (30 h fcst)
22 UTC 3 Sept (22 h fcst)
11 UTC 4 Sept (35 h fcst)
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Experimental Hurricane Analyses
Wind from Numerical Forecast
Electric Grid Damage
Likelihood of Wind Damage
Electric Grid Restoration
Brian Bush pc 2005
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Plans
We are getting there!
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Data Assimilation Plans
t=0
• Develop WRF-based Data Assimilation
Systems:
Observation
t = 3 hr
– WRF 4DVAR (AFWA)
– WRF EnKF (DAI)
• Assimilation Algorithm Research:
– Compare 3DVAR, 4DVAR, and EnKF on
radar data assimilation (USWRP)
• Data Impact Studies:
– MODIS winds over Antarctic (NASA)
– Radar radial velocity and reflectivity (RAL,
CRIEPPI, USWRP)
– GPS radio occultation data (NSF/OPP,
COSMIC)
– Ground-based GPS water vapor data
(COSMIC, CRIEPPI)
t = 0 Model Forecast t = 3 hr
• Operational Applications:
– NCAR ÆAMPS
– International collaborations (Korea, Taiwan,
India, China, Italy, …)
– AFWA
3-h forecast of the June 12, 2002 squall line in IHOP
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WRF Plans
ƒ
Community WRF
ƒ
Continue workshops, tutorials and support of WRF to the research community
ƒ Applications
ƒ
and testing
ƒ
Transition Antarctic real-time forecasting (AMPS) to ARW and to new supercomputer
ƒ
Continue support for high-resolution real-time WRF forecasting by DTC
ƒ
Continue hurricane prediction, make available to TPC
ƒ
Conduct ARW forecasts to support field experiments (e.g. MIRAGE)
New research directions
ƒ
Explore new verification measures for high-resolution NWP
ƒ
Couple ARW with ocean model for hurricane research and forecasting
ƒ
Expand capabilities for air quality and chemistry applications (WRF-Chem)
ƒ
Continue to develop nested regional climate modeling program at NCAR
ƒ
Develop global ARW
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Nested Regional Climate Model
Goals:
• Improved downscaling from global climate simulations to
accurate regional predictions;
• Upscaling from regional processes, including the effects
of land and ocean processes; and,
• Understanding and simulating the manner in which
mesoscale organization of moist convection impacts
larger scales, including: tropical modes, tropical cyclones
and extratropical (PNA) interactions.
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Initial NRCM Configuration
• Tropical Channel, 1-way nested into NCEP or CAM
• Surface Specified
• Combination of 1- and 2-way nested internal grids, down to
4km resolution.
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Thank You
Understanding
Application
Facilities
Dynamics &
Scale
Interactions Prediction
<48 h Weather
Prediction
WRF
Boundary
Atmos.
Precip.
Processes Chemistry Layer
Data
Assimilation
DA System
Air
Quality
NRCM
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