the Convection-Permitting Model at JMA Tadashi Fujita, Yoshihiro - - PowerPoint PPT Presentation
Development of the Operational Data Assimilation System for Rapid and Frequent Updates of Forecast with the Convection-Permitting Model at JMA Tadashi Fujita, Yoshihiro Ishikawa, Yasutaka Ikuta, Kosuke Ono, Kensuke Ishii, Koichi Yoshimoto,
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Domain 1581 x 1301 covering the whole Japan
Local NWP System Local Forecast Model (LFM) Local Analysis (LA) Global NWP System Global Spectral Model (GSM) Global Analysis (GA) Meso-Scale NWP System Meso-Scale Model(MSM) Meso-Scale Analysis (MA)
Resolution ~20km Resolution 5km Resolution 2km
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– Explicit representation of spatial and temporal variations at fine scale – More realistic terrain help resolve terrain induced phenomena mitigate representativeness error in use of surface observations
– Frequently provide an enhanced forecast with information from the latest observations. – Hourly operation of rapid forecasts using an efficient system.
4
Meso(5km)
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Local(2km)
High mountains and valleys are more realistically resolved.
14 Jul. 2012 01UTC 1-hour accumulated precipitation
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LFM predicts two line shaped heavy precipitation areas. High resolution helps better representing the strong vertical transportation of convection.
00 03 06 09 12 15 18 21 00 Da12 Da18 Da00 Da06 Ea00 Ef00 Ea06 Ef06 Ea12 Ef12 Ea18 Ef18 Ma00 Mf00 Ma03 Mf03 Ma06 Mf06 Ma09 Mf09 Ma12 Mf12 Ma15 Mf15 Ma18 Mf18 Ma21 Mf21
La 00 Lf 00 La 01 Lf 01 La 02 Lf 02 La 03 Lf 03 La 04 Lf 04 La 05 Lf 05 La 06 Lf 06 La 07 Lf 07 La 08 Lf 08 La 09 Lf 09 La 10 Lf 10 La 11 Lf 11 La 12 Lf 12 La 13 Lf 13 La 14 Lf 14 La 15 Lf 15 La 16 Lf 16 La 17 Lf 17 La 18 Lf 18 La 19 Lf 19 La 20 Lf 20 La 21 Lf 21 La 22 Lf 22 La 23 Lf 23
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~20km 2km 5km
Local NWP System：High Frequency Operation
latest observations.
Da: Global Cycle Analysis Ea: Global Early Analysis Ef: Global Forecast Ma:Mesoscale Analysis Mf: Mesoscale Forecast La: Local Analysis Lf:Local Forecast
Long cutoff-time: keeping quality of the entire system. Short cutoff-time: keeping distribution of products on schedule.
4D-Var 4D-Var 4D-Var 3D-Var
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FT=9
470min 410min
FT=8
350min
FT=7 FT=7 FT=9
390min
FT=6
290min
FT=5
230min
FT=6
210min
FT=4
170min
FT=3
110min
FT=2
50min
Lead Time LFM MSM
3 hourly updates. Results available by Initial time +150min. Frequent updates reflecting newly received observations. Results available by initial time + 70min.
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3h before LFM initial time
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G: Global Analysis, M: Meso-scale Analysis, L: Local Analysis ( ) : under development for introduction
surface observations.
as important sources of detailed information for forecasting high impact events. ・Development is in progress for introduction of satellite data (Brightness Temperature and Atmospheric Motion Vector).
Extensive use of data with high temporal resolution (rapid scan satellite data, etc.) is considered to be an important challenge in the future.
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(AMeDAS, SYNOP, SHIP, DRIFTER)
30 Sep. 2013 00UTC
MSM LF1 3DVAR Radar simulator Radar obs. Ze RH pseudo obs. Ze-RH Database
without Radar Ze with Radar Ze OBSERVATION Estimated RH PDF for different values of Ze
Altitude 3000m Ze RH
Kernel Density Estimation of PDF + Maximum Likelihood Estimation
WGNE Res. Activ. Atmos. Oceanic Modell., 42, 01.05-01.06.
3h accumulated precipitation 27 Jul. 2011, 18UTC
FT=3 FT=3 FT=2 FT=2 FT=1 FT=1 Observation Operational System Test System
2km
Incremental approach
2km 5km 5km
Updates of 1h accumulated Precipitation Forecasts (all valid at 06 Jul. 2012 11UTC from different initial times) new forecast
LFM LA LFM LA
Operational Test Contribute to improve spin-up of precipitation forecast, mitigating shock from different resolutions.
asuca (NL,TL,AD) Physics Library (NL,TL,AD)
(NL,TL,AD) External packages (NL,TL,AD) ex.: RTTOV 3D-Var 4D-Var +Hybrid asuca-Var core
Selector switch is implemented Interface for each observed element Wrapper for each package asuca-Var core is specialized to handle optimization and related processes
asuca-3DVar applied to the Local NWP
Test system asuca-Var + asuca(5km) => asuca(2km) Operational system JNoVA + JMA-NHM(5km)=> JMA-NHM(2km)
Observation
Non-linear, Tangent-linear and Adjoint codes
Forecast comparable to the operational one
1h precipitation 11 Jul. 2012, 22UTC
GPS TPW MTSAT-2 Clear Sky Radiance
MTSAT-2 contributes to greatly increase humidity information
Example of MTSTAT-2 Jacobian
dTb/dqv dTb/dT
altitude (km)
MTSAT-2 GPS
Altitude 8000m
bg sat v v
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The Local NWP is the finest resolution system in the JMA’s operational NWP system, aimed at providing information on aviation forecast and disaster prevention. The convection-permitting resolution of LFM allows enhanced prediction of high impact events. The system is featured with high frequency and rapid updates of forecasts using the latest observations. Use of radar obs. etc. contributes to a better forecast of high impact events. Various developments are in progress to improve the Local NWP system. These includes:
cycle), contributing to improve spin-up of precipitation forecast.
asuca-Var), achieving a comparable performance with the current operational Local NWP system.