Development of Meso-scale Numerical Model System in IHR Cui Chun-guang, Li Jun, Shi Yan Institute of Heavy Rain, CMA, Wuhan

Contents 1. Review of development history 2. Research and application of AREM 3. development in near future 2019/10/24 WHIHR

1. Review of development history 2019/10/24 WHIHR

From 1950’s to 1970’s barotropic model baroclinic dry model 2019/10/24 WHIHR

From 1980’s precipitation model 1985, CRONWS (Central China Regional Operational Numerical Weather forecasting System) -----Zhou Xiaoping 1990,MAPS（Mesoscale Analyses and Prediction System)-----Yu Kangqing Middle-late 1990’s ,AREM (Advanced Regional Eta Model) -----Yu Rucong MM5, Grapes etc. 2019/10/24 WHIHR

Application 1987 1995 CRONWS 1996 2004 MAPS AREM 1999 2019/10/24 WHIHR

2. Research and application of AREM 2019/10/24 WHIHR

2.1 Main technical features -ladder topography coordinate Static deduction IAP variable transformation “half grid spacing difference scheme” of E-grid two-step shape-preserving advection scheme 2019/10/24 WHIHR

vertical ladder coordinate () Pt, =0 W, H K=1 U, V, T, Q K=1 W, H K=2 U, V, T, Q K=2 Ps, s Ps, s K=KM Mountain K=KM Ps, s K=KM+1 2019/10/24 WHIHR

V T Schematic Diagram to illustrate the finite difference scheme on E-grid T V Assumed point 2019/10/24 WHIHR

two-step shape-preserving advection scheme (Yu Rucong,1994)： guarantee the calculation facticity of water vapor transfer directly associated with rainstorm 2019/10/24 WHIHR

2019/10/24 WHIHR

2.2 Development course of AREM From 1999 to 2003 Rem AremV2.1 AremV2.3 AremV3.0 2019/10/24 WHIHR

Improvements of AREM Resolution: 75Km 6Km 2019/10/24 WHIHR

Time-variation boundary Improvements of AREM Lateral boundary and upper boundary conditions: Fixed boundary 100hPa Time-variation boundary 10hPa 2019/10/24 WHIHR

Non-local boundary scheme Improvements of AREM Lower boundary conditions: Non-local boundary scheme 2019/10/24 WHIHR

Improvements of AREM Physics options: Cold cloud micro-physics process Betts convection adjustment Saturation condensation 2019/10/24 WHIHR

Improvements of AREM Surface flux and radiation: Bulk permutation method CLM land surface process Unabridged radiation process 2019/10/24 WHIHR

3-dimensional variation Improvements of AREM Initial conditions: Advanced Barnes 3-dimensional variation 2019/10/24 WHIHR

2.3 AREM capability examination 2019/10/24 WHIHR

Geographic distribution of Heavy rain in China Northern heavy rain Northeastern heavy rain Jul 20th~Agu 10th Meiyu front heavy rain in Yangtze River valley Jun~Jul Southern heavy rain in former flood season May~ Jun 10th 2019/10/24 WHIHR

Forecast experiments of heavy rain in Yangtse River valley 2019/10/24 WHIHR

heavy rain event in South Henan province in Jul 16th,2004 OBS 12km 2019/10/24 WHIHR

heavy rain event in Yangjiang city, Guangdong province in May 7th,2004 experiments of heavy rain in South China heavy rain event in Yangjiang city, Guangdong province in May 7th,2004 12KM OBS 37KM 6KM 2019/10/24 WHIHR

simulated 3-D cloud planform(0.1g/kg equivalence level) Numerical simulation to Typhoon Rananim simulated 3-D cloud planform(0.1g/kg equivalence level) 0600 UTC 12AUG2004 0700 UTC 12AUG2004 0800 UTC 12AUG2004 Infrared satellite cloud chart 2019/10/24 WHIHR

precipitation rate (mm/h) and 700 hPa streamline field 2019/10/24 WHIHR

track of Typhoon Rananim Red line: observed Blue line: simulated 12Z12 Red line: observed Blue line: simulated 06Z12 00Z12 18Z11 12Z11 2019/10/24 WHIHR

(averaged between 110°E and 122.5°E) Time-Meridional cross section of daily mean precipitation rate in JJA 2003 (averaged between 110°E and 122.5°E) OBS AREM 2019/10/24 WHIHR

Northeast China North China South China 2019/10/24 WHIHR

2019/10/24 WHIHR

Black-simulated red-observed Max green-observed mean Evolution in Precipitation Rate in mm/h Hourly precipitation in Wuhan region during 20th-22th Jul,1998 Observed Max. Simulated Observed Mean Black-simulated red-observed Max green-observed mean 2019/10/24 WHIHR

Contrast between AREM with other models 2003 2004 Grade AREM MM5 JAPAN Parameter Grade AREM MM5 JAPAN T213   TS Ⅰ 66 43 49 51 Ⅱ 50 33 36 35 Ⅲ 42 24 30 28 Ⅳ 31 16 21 Ⅴ 10 11 PO 17 44 13 3 14 34 62 39 69 82 74 79 83 NH 23 46 47 54 60 45 65 64 53 72 61 78 85 77 Contrast between AREM with other models Parameter Grade AREM MM5 JAPAN T213   TS Ⅰ 65 57 58 54 Ⅱ 51 41 46 37 Ⅲ 39 28 Ⅳ 23 15 30 10 Ⅴ 9 5 1 PO 22 7 4 8 16 38 62 29 45 78 61 86 85 92 90 99 NH 32 44 40 52 60 48 64 63 68 75 83 89 67 94 2003 2004 2019/10/24 WHIHR

vertical structure of precipitation rate AREM system can well describe all kinds of heavy rain events in China regions to the east of Qinghai-Tibet Plateau on following aspects : rainband feature, intensity, vertical structure of precipitation rate evolvement of hourly rainfall. 2019/10/24 WHIHR

Preliminary Test of 3-DVAR Variation analysis based on Grapes/3DVAR system 1DVAR assimilation of precipitation By Adjusting humidity and temperature profile 3DVAR assimilation of radar wind field 3DVAR of ATOVS 2019/10/24 WHIHR

Precipitation forecast capability is improved greatly by 3DVAR 3DVAR（red）and successive correction（blue） Precipitation forecast capability is improved greatly by 3DVAR 2019/10/24 WHIHR

Real distribution of precipitation over 25mm during Jul 8th-9th,2003 08:00 AM (unit:mm) 2019/10/24 WHIHR

Simulative 24h precipitation during Jul 8th-9th,2003 08:00 AM( unit: mm) Wuhan & Yichand radars wind field assimilation Without radar wind field assimilation 2019/10/24 WHIHR

2.4 product distribution 2019/10/24 WHIHR

Publish online 3D display 2019/10/24 WHIHR

3. Development in near future 2019/10/24 WHIHR

Improvements on physics scheme: cloud and rain course boundary layer scheme radiation course surface flux parameterization 2019/10/24 WHIHR

Research on data assimilation technique To develop schemes with the capability of assimilating such as : radar reflectivity and wind , satellite data, wind profile GPS water vapor content, rain gauge data surface station etc. 2019/10/24 WHIHR

Research on data assimilation technique (continued) Learn from RUC system and LAPS to build a meso-scale reanalysis system wish to cooperate with NSSL and FSL 2019/10/24 WHIHR

Research on short-term ensemble forecast technique Based on initial field disturbance 2019/10/24 WHIHR

Interpretation technique of model forecast product 2019/10/24 WHIHR

Application technique of QPF on other areas Flood forecast based on Hydrology-meteorology models coupling Prediction of geological disaster caused by heavy rain 2019/10/24 WHIHR

AREM system in developing… Meso-scale reanalysis System based on 3/4Dvar NCEP T213 Meso-scale reanalysis field Ensemble forecast based on initial disturbance AREM lateral condition provided by T213 forecasting field First Guess Fields Weather forecast Geological disaster Environment forecast Numerical simulation Hydrological application Education & training 2019/10/24 WHIHR

Thanks ! 2019/10/24 WHIHR