JMA Global Model Hiromi Owada Numerical Prediction Division, Forecast Dept. Japan Meteorological Agency 1

Contents JMA Global Spectral Model (GSM) – Overview of GSM – Model performance Ensemble Prediction System (EPS) – One-week EPS (WEPS) – Typhoon EPS (TEPS) Model products – Deterministic forecast products – EPS products – GIFS-TIGGE products – Early warning products for extreme weather events 2

Current NWP models of NPD/JMA Global Spectral Model (GSM) Meso-Scale Model (MSM) Local Forecast Model (LFM) One-week Ensemble (WEPS) Typhoon Ensemble (TEPS) Objectives Short- and Medium- range forecast Disaster prevention Aviation forecast Disaster prevention One-week forecastTyphoon forecast Forecast domainGlobal Japan and its surroundings (4080 km x 3300 km) Eastern part of Japan (1100 km x 1600 km) Global Horizontal resolution TL959 ( deg., ~20km) 5 km2 km TL319 ( deg., ~55km) Vertical levels / Top hPa km km hPa Forecast Hours (Initial time) 84 hours (00, 06, 18 UTC) 264 hours (12 UTC) 15 hours (00, 06, 12, 18UTC) 33 hours (03, 09, 15, 21UTC) 9 hours 264 hours (12 UTC) 51 members 132 hours (00, 06, 12, 18 UTC) 11 members Initial Condition Global Analysis (4D-Var) Meso-scale Analysis (4D-Var) Local Analysis (3D-Var) Global Analysis with ensemble perturbations Perturbations are produced by SV- method As of 28 March,

Main Operational NWP Systems at JMA Regional NWP system Horizontal Resolution: 5 km Updates: 8 times a day Forecast domain: Japan and its surrounding areas Global NWP system Horizontal Resolution: 20 km Updates: 4 times a day Forecast domain: Global 4

Roles of GSM basic information for short-range and one week forecasts basic information for typhoon track and intensity forecasts assist of aviation and ship routing forecasts provision of lateral boundary condition for Meso-Scale Model input data for ocean wave model and regional storm surge model wind information for input of chemical transport model 5

NWP models in the world Nation (Center) Global modelGlobal EPS Regional model Resolution Forecast period Resolution Member s x runs per day Forecast period Resolution Japan (JMA)20km L6011 days55km L6051x111 days 5km L50 2km L60 Europe (ECMWF)16km L9110 days 32km L62 65km L62 51x2 10 days +5 days - U.K. (Met Office)25km L706 days 33km L70 60km L70 44x4 22x2 3 days 15 days 12km L70 1.4km L70 France (Meteo France)25km L704 days37km L6535x24 days7.5km L70 Germany (DWD)20km L607 days- 7km L40 2.8km L50 U.S.A. (NCEP) 27km L64 105km L64 8 days 16 days 70km L42 90km L42 21x4 8 days +8 days 12km L60 4km L50 Canada (CMC)25km L8010 days66km L7420x216 days 10km L80 2.5km L58 As of 28 March,

Data Assimilation & Forecast 7 The First Guess The last forecast Various Observations Increment Initial ConditionThe next forecast Data AssimilationNWP forecast In the DA system, the given model state (first guess) is corrected using various observations information with the constraints in the NWP model. In the “cyclic operation”, the first guess is the forecast from the latest DA result.

8 Observations used in JMA NWP 8 Direct observations Buoy (image : JMA) Aviation Remote sensing Bogus Typhoon bogus GEO satellites METEOSAT (image : ESA) LEO satellites Semi-operational Earth- observing sat. GNSS RO GRACE COSMIC (image : UCAR) GRACE-A (image : NASA) Upper air sounding (Image : JMA) Land surface observation (image : JMA) Sea surface observation (image : JMA) Wind profiler (image : JMA) GPS (image : JMA) Doppler radar (image : JMA) MTSAT (image : JMA) GOES (image : NOAA) NOAA (image : NOAA) Metop (image : ESA) DMSP (image : NASA Aqua (image : NASA Terra (image : NASA TRMM (image : NASA

Data used in DA 9 SYNOP:N=16819 TEMP:N=626 SHIP:N=3803 BUOY:N=6245 PILOT:N=319 WPROF:N=1864 AVIA:N=43853ASCAT:N=5939 ALL:N=11852ALL:N=18278 ALL:N=14221ALL:N=11084 ALL:N=21577 ALL:N=25796 ALL:N=161778

Necessity of typhoon bogus It is important to analyze TC correctly for accurate forecast. – Different initial fields yield different forecast results. Location, size, intensity, … In many cases, observational data do not exist around a TC to represent its structure properly (A TC locates in the ocean). Therefore, pseudo-observational data generated based on position and intensity analyzed by forecasters is used. 10

Model performance & verification 11

Verification Score RMSE of 500 hPa geopotential height in Northern Hemisphere (20-90N) (bar: annual mean) The accuracy of 72hr forecast in 2012 compares with that of 24hr forecast in 1980’s hour 24hour Smaller error

GSM RMSE Sequence on Z500 for 120 hrs forecast at N.H. 13 T213L30 Revision of cumulus parameterization Revision of cloud Use of MODIS Revision of radiation TL319L40 4D-Var Direct use of ATOVS 3D-Var Variational bias correction T213L40  TL959L60 Revision of VarBC Use of CSR Use of SSMIS, Use of ASCAT Use of COSMIC Use of QuikSCAT Use of SSM/I and TMI  TL959L60  Reduced Grid TL319(Inner loop) Revision of stratocumulus cloud scheme Revision of GNSS RO usage As of March 2013

Ensemble Prediction System (EPS) 14

Probabilistic Forecast Very small initial error With the probabilistic forecast, we could know the confidence information of the forecast. Color shows probability With the integration, the deterministic forecast has large error The error grows rapidly Atmospheric State Forecast Time Atmospheric State The range of initial error Truth Forecast 15

Ensemble Prediction Systems In the EPS, the multiple forecasts are conducted using slightly different initial conditions and/or different forecast settings. – This is a form of Monte Carlo analysis. Initial ConditionFT48FT120FT216 Perturbations in the initial condition are very small Perturbations in the 9-days forecast are quite large. Spaghetti diagram [51-member P msl forecasts] Forecast time 16

Ensemble Prediction Systems One Week EPS (WEPS) Typhoon EPS (TEPS) Objectives One-week probabilistic forecast Typhoon forecast Forecast DomainThe whole Globe Forecast Horizontal Resolution T L 319 (0.5625deg., ~55km) Vertical Levels 60 Levels, up to 0.1 hPa Forecast Hours264 hours (12UTC) 132 hours(00,06,12,18) If Tropical Cyclones exist or will exist in the responsible area Enemble Settings Member 1 control run and 50 perturbed runs 1 control run and 10 perturbed runs Initial perturbation SV method, 3 target areas (NH,TR,SH) SV method, RSMC target (Fixed Target) and Max. 3 Typhoon Target (Moving Target) Model ensembleStochastic Physics 17 As of 28 March, 2013

18 JMA One-week Ensemble Prediction System One-week Ensemble Prediction System ( outline ) – 51 members forecast run. – 264 hour forecast (12 UTC initial) is operated everyday. – Horizontal resolution is deg = 51 global predictions for one ensemble forecast starting at one initial time. ……

Typhoon Ensemble Prediction System For 5-day typhoon track forecast – 6hourly, 11member, 132hours forecast – Used in typhoon track probability forecast 19 Typhoon track forecast of GSM TEPS typhoon track forecasts of All the ensemble members TEPS probability information Strike Probability Map Ensemble Mean GSM Higher Risk Relatively Low Risk Best Track

Forecast products 20

JMA High-Resolution GSM Data Service Target: NMHSs – Mainly in WMO Region II Model: GSM(TL959) Data Format: GRIB2 Preservation Term: Latest 9 days 21

Profile (WMO Region II) Upper AirSurface Resolution0.5deg (331 x 191)0.25deg (661 x 381) RegionLon: 30E – 180 – 165W, Lat: 5S – 90N Initial Time00, 06, 12, 18 UTC (4 times per day) Forecast Time00 to 84 hours by 3 hours (any initials) 90 to 216 hours by 6 hours (12UTC initial only) Levels21 (1000, 975, 950, 925, 900, 850, 800, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10 hPa) * Separated 21 files by levels 1 (surface) ElementsU, V, T, Rh, Z, Omg Stream Function, Velocity Potential (at 850, 250 hPa) Vorticity (at 500 hPa) U, V, T, Rh, Ps, Psea, Rain, Cloudiness (total, high, middle, low) File size (gzip compressed) 500 – 700KB800KB3MB 22

GSM products on WIS Portal JMA DDB server discontinued operation at the end of February, GSM products continue to be available through a new server at MITIGATION GUIDE FOR DDB USERS is at: jma.go.jp/cms/wp- content/uploads/2012/09/Migration Guide_DDB_ver1.pdf – Changes from DDB – How to download GSM products from the new server? 23

JMA SWFDP webpage 24 URL: jma.go.jp/swfdp/ Products Deterministic Forecast from Global Model Probabilistic Forecast from Global medium- range EPS MTSAT Products TIGGE Products Products for the past 10 days are available.

JMA EPS-WEB 25 operated as a part of a pilot project of JMA aiming at improving the EPS and increasing the availability of its products. provides the visualized EPS product for supporting the activity of National Meteorological and Hydrological Services (NMHSs) in Asia.

Summary The outline of JMA Global Spectral Model (GSM) was introduced. With its high resolution, GSM supports short- to medium-range forecasts, typhoon (track and intensity) forecast. The “forecast confidence information” is important for the disaster risk management. To provide such information, JMA operates One-week EPS (WEPS) and Typhoon EPS (TEPS). Forecast products available to NMHSs in SeA are introduced. – High-Resolution GSM Data Service, JMA webpage for SWFDP, etc. 26

References Japan Meteorological Agency, 2013, Outline of the Operational Numerical Weather Prediction at the Japan Meteorological Agency. 27