Current Status and Future Plans for KMA Data Assimilation System
Dec, 2016
Current Status and Future Plans for KMA Data Assimilation System
Dec, 2016
Hyun-Cheol Shin, Eun Joo Lee, Eun Hee Lee, Jung-Rim Lee, Eun-Hee Kim,
Hyeyoung Kim, Heejung Kang, Adam Clayton*, Sangwon Joo
Korea Meteorological Administration, UKMO *
2
Contents
� General introduction of KMA NWP system
� Improvements of Global (17km) and Local (1.5km) model in 2016
� KIAPS (Korea Institute of Atmospheric Prediction Systems) Project
� Issues for Future Strategy
3
KMA NWP Performance
2nd supercomputer
1st supercomputer
3rd supercomputer
4th suppercomputer(’15-’16)
Introduction of UM(2010)
90 times
37 times
8.5 times ( 5.8PFlops )
Introduction of supercomputer(1999~) +
NWP Performance
significantly improved
Big gap reduced
Similar Performance to JMA
• 1 TF (Tera Flops) : 1 trillion (1,000,000,000,000) calculations in a second
corresponds the amount that 800,000 people can calculate in a year
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Recent improvements
[ Global model] (2016.6)� Resolution : 25km � 17km / Version Upgrade
� New satellite species (6) : ATMS, Geocloud, GroundGPS, CrIS, MVIRI, SEVIRI
� Dynamics : New Dynamics (ND) � End Game (EG)
[ Global Ensemble ] (2016.6)� Resolution & Members : 40km � 32 km / 24 � 49 members
� Dynamics : New Dynamics (ND) � End Game (EG)
� Version Upgrade
[Regional model] (2015.6)� DA tuning : Typhoon bogus, Satellite data thinning, Soil moisture update
� Model ancillary : Aerosol
[Local model] (2016.6)
� Domain extended (LDPS � XLDPS) / Version upgrade� Dynamics : New Dynamics (ND) � End Game (EG)
[Local Ensemble] (2016.6)
� Version upgrade
� Dynamics : New Dynamics (ND) � End Game (EG)
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KMA Operational NWP system (2016.6)
E-ASIA (ND)
•UM 12kmL70
(top=80km)
•Target Length
87hrs/72hrs (6 hourly)
• Initialization :
4DVAR
GLOBAL (EG)
• Resolution
N768L70 (UM)
(~17km / top = 80km)
• Target Length
288hrs (00/12UTC)
87hrs (06/18UTC)
• Initialization : Hybrid
Ensemble 4DVAR
Global EPS (EG)(EG)(EG)(EG)
• Resolution
N400L70 (UM)
(~32km/ top =80km)
• Target Length
288hrs
• IC : GDAPS
• # of Members : 49
• Perturbation : ETKF,
RP, SKEB200,12: 288hrs : 25 members [including cntl]
06,18: 9hrs: 49 members [including cntl]
LOCAL (XLDPS) ((((EEEEGGGG))))
• Resolution
1.5kmL70 (UM)(744×928 / top =39km)
• Target Length
36hrs (3 hourly cycle)
• Initialization : 3DVAR
LOCAL Ensemble (EG)• Resolution 3kmL70 (UM)
• Target Length : 72hrs
• # of members : 13 (including CNTL)
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Observation species used in NWP models
[ Global model]� 15 observation species used in global model
- Conventional data (3 species) : Surface, Sonde, Aircraft
- Satellite data (12 species) : Scatwind, Satwind, ATOVS, AIRS, IASI, GPSRO, ATMS, Geocloud, GroundGPS, CrIS, MVIRI, SEVIRI
� ATMS, Geocloud, GroundGPS, CrIS, MVIRI, SEVIRI assimilated from 2016 with
17km global model
[Regional model]
� 9 observation species used in regional model- Conventional data (3 species) : Surface, Sonde, Aircraft
- Satellite data (6 species) : Scatwind, Satwind, ATOVS, AIRS, IASI, GPSRO,
[Local model]
� 4 observation species used in Local model
- Conventional data (3 species) : Surface, Sonde, Aircraft- Satellite data (1 species) : Scatwind (+Ground-GNSS, Himawari-AMV, AMSU-B, IASI)
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Received Data / Used Data
� Ratio of used data against received data
� Global Model : GPSRO (largest ratio) > Surface > Sonde > ATMS
� Less than 10 % : Satellite data (Scatwind, Satwind, ATOVS, GroundGPS,
SEVIRIClear, MVIRIClear, GOESClear), Removed Mainly By Thinning
� Total ratio : Local model (16.6%) > Global model (8.1%) > Regional model (3.2%)
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N768 2016041700N768 2016041700N768 2016041700N768 2016041700
Used Data (Global - UKMO / KMA)
� 83 % used compared with UKMO
� 2.5 % increased ratio than N512(25km) after N768(17km) was installed
� GOES Clear, ATMS, CrIS, MVIRIClear, Ground GPS added compared with N512(25km)
� But SSMIS, SEVIRIClear, AMSR, MWSFY3C, MTSAPHIR not used
Less OBS used than UKMO : Mainly due to …
- Different cut off time (+6:25 : +6:40) - Longer route to get obs
- Different QC (OPS) version
~
Improvements of Global NWP System (2016)Improvements of Global NWP System (2016)
� Resolution : 25km � 17km / Version Upgrade� New satellite species : ATMS, Geocloud, GroundGPS, CrIS, MVIRI, SEVIRI
� Dynamics : New Dynamics (ND) � End Game (EG)
Verification (RMSE)
25km(old)
17km(new)
25km(old)
17km(new)
2015.7 (summer) 2016.1 (winter)
500hPa Z 00 UTC 12UTC
Analysisverification
6.6% 6.8%
Observationverification
6.2% 9.7%
500hPa Z 00 UTC 12UTC
Analysisverification
1.9% 4.8%
Observationverification
1.0% 7%
Average improvements (all levels and lead times, 4 variables) summer winter
Analysis verification 14.2 % 4.1 %
Observation verification 7.3 % 4.3 %
Improvements
Greatly improved for most cases. Maximum improvement 14 %
500 hPa Z RMSE reduced for all forecast times
Verification Period : 2015. 7.
Target Typhoons : 9th - 12th Typhoon in 2015 (4 typhoons)
Typhoon Track Error (1509, 1510, 1511,1512)
Initial Central Pressure of Typhoon
Typhoon Track Error (Average forecast Error for 120 hour forecast, km)
• Typhoon track and intensity forecast improved
25km(old)
17km(new)
25km(old)
17km(new)
25km(old)
17km(new)
25km(old)
17km(new)
1509 1510 1511 1512
25km(old)
17km(new)
best
25km(old)
17km(new)
best
25km(old)
17km(new)
best
25km(old)
17km(new)
best
Typhoon Forecast Verification
Significantly reduced track error
More realistic intensity
Improvements of Local NWP System (2016)Improvements of Local NWP System (2016)
� Domain extended (LDPS � XLDPS) / Version upgrade� Dynamics : New Dynamics (ND) � End Game (EG)
국립기상과학원
국립기상과학원국립기상과학원
국립기상과학원 | National Institute of Meteorological Research
XLDAPSXLDAPSXLDAPSXLDAPS
• Extended reduced resolution zones
- to reduce strong impact from the boundary fields
4x4km
4x4km 4x4km
4x4km1.5x4km
1.5x4km
4x1.5km 4x1.5km
1.5x1.5km
Extended LDAPS domain(XLDAPS)
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LDPS domain vs. XLDPS domain
LDPS ( ) XLDAPS ( )
622X810
622X810622X810
622X810
1.5km X 1.5km
1.5km X 1.5km1.5km X 1.5km
1.5km X 1.5km
2
4km X 4km
4km X 4km4km X 4km
4km X 4km 1.5km X 4km
1.5km X 4km1.5km X 4km
1.5km X 4km 4km X 4km
4km X 4km4km X 4km
4km X 4km
4km X 1.5km
4km X 1.5km4km X 1.5km
4km X 1.5km 4km X 1.5km
4km X 1.5km4km X 1.5km
4km X 1.5km
1.5km X 4km
1.5km X 4km1.5km X 4km
1.5km X 4km4km X 4km
4km X 4km4km X 4km
4km X 4km 4km X 4km
4km X 4km4km X 4km
4km X 4km
622X810
622X810622X810
622X810
1.5km X 1.5km
1.5km X 1.5km1.5km X 1.5km
1.5km X 1.5km
744X928744X928744X928744X928 1188X11481188X11481188X11481188X1148
Same fixed grid area / Variable grid area extendedNew Dynamics (Vn 8.2) � End Game(Vn 10.1 )
Number of used observations
Surface : 2696 � 5160 : 1.9 times increase Sonde : 50 � 101 : 2 times increaseAircraft : 238 � 2407 : 10 times increase Scatwind : 155 � 580 : 3.8 times increase
LDPS XLDPS LDPS XLDPS
Analysis Verification (RMSE, 2015.7)
MSLP – 925 hPa height : LDPS better than XLDPS 500 hPa Z improved 850hPa – 100 hPa height : XLDPS better than LDPS
Temperature & Wind : improved for all cases
Precipitation verification
3 hourly accumulated precipitation
Generally improved
Observation verification
Analysis verification, precipitation verification : XLDPS better than LDPSObservation verification : LDPS better than XLDPS (except RH)Summer case showed better performance than winter case
VLDPS XLDPS
Resolution 1.5km 1.5km
Levels 70 layers 70 layers
Cycle Interval 1 hourly 3 hourly
DA 3DVAR 3DVAR
Visibilityassimilation
Yes No
4DVAR Plan 2017 2018
Operational use 2016.12 2016.6
Forecast hours 12 hours 36 hours
Others ICE-POP -
Future plan VLDPS
VLDPS : Very Short Range forecast model
4km Regional Model4km Regional Model
� Resolution : 12km � 4km� UM version : New Dynamics � EndGame
� DA Versions improved
Future plan 4km Model
0
2
4
6
8
10
12
14
6 12 18 24 30 36
RM
SE
Forecast time(hour)
GPH_500hPa
RDPS12
RDPS4_DA
0
1
2
3
4
5
6
7
8
6 12 18 24 30 36
RM
SE
Forecast time(hour)
WIND_250hPa
RDPS12
RDPS4_DA
Initial version of 4km regional model gave improved resultsStrategic decision among 4km regional model, XLDPS and VLDPS
KIAPS Project(Korea Institute of Atmospheric Prediction Systems)KIAPS Project(Korea Institute of Atmospheric Prediction Systems)
Courtesy of I-H.Kwon (KIAPS)
KIM-SH(High Order Method Modeling
Environment model; NCAR’s CAM-SE)
KIM-SW(Kiaps Integrated Model – Spectral
element method, WRF-Type)
Numerical method
Spectral Element method (Eulerian)
Spherical grid Cubed-sphere (Equi-angular gnomonic projection)
Spatial approximation
piecewise polynomials of degree 3
EquationHydrostatic
(Full variables)Non-hydrostatic
(Perturbation variables)
Temporalapproximation
Fully ExplicitLeapfrog, first-order due to
Robert-Asselin filter
Split-explicit RK3, second-order for nonlinear equation
Explicit spatialdiffusion
4th order linear horizontal diffusion
6th order horizontal diffusion + divergence damping
Cubed sphere grid structure global modeCubed sphere grid structure global modeCubed sphere grid structure global modeCubed sphere grid structure global mode
Horizontal resolution: NE120NP4 ~ 25km Vertical resolution: 50 levels with 0.3 hPa top
KIAPS Integrated Model (KIM) model
Global model25 km � 12km or 6km
Ensemble model50km � 25km(?)50 members
DALETKF, 3DVAR� 4DEnVAR
25
� Global NWP system
- Follow up the trace of UKMO ; Almost real time update
- 17km L70 (‘16) � 10km L70 (‘18)
� Limited area model
- Optimization for East Asia : Best performance in our area !
- 4km Regional model ? 1.5 km local model ?
� KIM (KIAPS Integrated Model)
- (25km � 12km) / 4DEnVAR (‘19)
- Start of parallel cycle with UM (‘17-’18)
- How to use UM and KIMS efficiently
- Stable transition to KIM
Issues for Future Strategy
� Daily verification by forecastersECMWF : UM : KIM
ECMWF UM KIM