the brazilian effort on the global model

Workshop on Weather and Seazonal Climate Modeling at INPE - 08-10 Dec 2008Workshop on Weather and Seazonal Climate Modeling at INPE - 08-10 Dec 2008

Center for Weather Forecasting and Climate Studies - CPTEC/INPECenter for Weather Forecasting and Climate Studies - CPTEC/INPE

The Brazilian Effort on the The Brazilian Effort on the Global ModelGlobal Model

By

José Paulo Bonatti



Global Atmospheric Spectral Model Origin:• NMC (USA National Meteorological Center, 1988) - NCEP• COLA (Center for Ocean-Land-Atmosphere Studies)• Rhomboidal Version 1.7+1.12 Fortran 77 from COLA

CPTEC Version:• Triangular CPTEC/INPE• User defined Horizontal and Vertical Resolutions• Sigma at Vertical and Spherical at Horizontal Coordinates• Full Quadratic Gaussian, Reduced and Linear Grids• Optimizations: Vectorization, MPI/OpenMP Paralelism• Fortran 90/95 Features: Dynamical Allocation, Modules, etc



Global Atmospheric Spectral Model

• Spectral Coeficients Initial Conditions: Topography (Truncated and Smoothed if desired), Log of Surface Pressure, Virtual Temperature, Vorticity, Divergence, Specific Humidity

• Grid Initial Sea Surface Temperature: Monthy or Weekly Mean (Climatological or Observed)

• Grid Initial Soil Moisture: Climatological or Real Time Analysed

• Grid Initial Climatological Fields: Snow, Deep Soil Temperature, Roughness Length

• Grid Initial Ozone: Climatological Zonal Mean (Interpolated at Each Time Step) or 3-Dimensional Field Analysis (NCEP)

• Boundary Conditions: Vertical Sigma Velocity Null at Top and Surface

• CO2 Amount: Fixed Value for All Atmosphere




• Initialization:

• Diabatic Non-Linear Normal Mode

Spectral Dynamic:

• Primitive Equations (Zonal and Meridional Winds)

• Spectral at Horizontal (Spherical Harmonics) and Finite Differences at Vertical and Time

• Semi-Implicit Time Integration (Eulerian and 3 Steps Semi-Lagrangean) and Asselin Filter



Global Atmospheric Spectral Model• Physical Processes:

� Surface:

• Land: SSiB (Xue, 1990, SiB - Sellers et al, 1986)

• Ocean: Bulk Aerodynamic Scheme (NCEP, 1988)

� Planetary Boundary Layer:

• Vertical Turbulent Diffusion 2.0 (Mellor and Yamada, 1982)

• Gravity Wave Drag (NCEP, 1988)

� Radiation:

• Short Wave Every Hour (Lacis and Hanson, 1974)

• Long Wave Every Three Hours (Harshvardhan et al, 1974)

• Short Wave CLIRAD (Tarasova, 2006)

• Cloud Radiation Interactions (Slingo, 1987)




• Physical Processes:

� Convection:

• Deep: KUO (Kuo, 1965; Anthes, 1977), RAS (Moorthi & Suarez, 1992) or Grell (2002) From Newest MM5 (Ensemble or Other Clousure)

• Shallow: Tiedke (1983) or Souza (1999)

� “Adjustments”:

• Large Scale Condensation: NCEP (1988)

• Horizontal Diffusion: Bi-Harmonical Explicit (NCEP, 1988) or 2n-Harmonical Implicit (CPTEC, 2002)

• CFL Control: Local Diffusion (COLA/CPTEC, 1995) or Enhanced Diffusion (ECMWF, 1999)



Operational Global Model EvolutionOperational Global Model Evolution

• 1994, NEC/SX-3: TQ0062L028 (210 km), CPTEC-COLA, t=1200s, sequential

• 1998, NEC/SX-4: TQ0062L028 (210 km), CPTEC-COLA, t=1200s, parallel up to 8 processors, NEC primitives

• 2000, NEC/SX4: TQ0126L028 (105 km), CPTEC-COLA, t=600s, parallel up to 8 processors, NEC primitives

• 2005, NEC/SX6: TQ0213L042 (63 km), CPTEC-OMP, t=400s, parallel up to 8 processors, portable

• 2007, NEC/SX6: TQ0299L064 (45 km), CPTEC-MPI, t=240s, parallel up to 32 processors, portable



Operational Global Models at CPTEC Two times a day: 00 and 12 UTC:

• TQ0213L042 (63 km) 7 days (NCEP)

• TQ0299L064 (45 km) 7 days (NCEP)

• TQ0213L042 (63 km) 7 days (GPSAS/CPTEC)

• TQ0126L028 (105 km) 30 days (coupled MOM3)

• TQ0126L028 (105 km) 15 days (ensemble 15 members: perturbation EOF based 45°S, 30°N - perturbed fields: temperature and winds)

• TQ0062L028 (210 km) up to 6 months every month (ensemble 7x15=105 members: different physics (Kuo, RAS, Grell) with SST forecasted and Persisted Anomaly each physic, and Coupled (RAS)



• Goal for the NEC/SX6: run a TL0511L064 (TQ0341L064), 40 km, CPTEC-MPI-OMP, for 10 days forecasting, portable, using 32 processors in 2h30min.

• The goal was achieved in Setember 2007 with great advantage: it takes 1h22min, t=720s.

• Then we develop a TL0575L064 (TQ03820L64), 35 km, CPTEC-MPI-OMP that runs 10 days forecasting using 32 processors, t=720s, in 1h53min. This is ready for operation, but the suite is saturated.

• We also devolop a TQ0666L096 (20 km). Runs in NEC/SX6 and in a NEC/SUN cluster of 1100 processors (275 nodes with 2 dual core chips - AMD). This model will be operational at the new machine under bidding. It takes 56min for a day forecast at the NEC/SX6 using 32 processors, 4 MPI, 8 OpenMP, semi-Lagrangean time integration and reduced quadratic grid.



Software Development• Modernization (Fortran 90/95)

• Otimization

• Paralelism

• Portability

• Code: massive paralism (MPI over OpenMP)

• Time Integration: Eulerian or Semi-Lagrangean

• Grid: Quadratic or Linear; Full or Reduced

• Resolution: user defined via namelist

• Man Power: 3 men year for 10 years.



Undergoing Developments

• Radiation Scheme from Unified Model UKMet Office (Edwards and Slingo, 1996): short and long waves.

• Massive Paralel Version MPI/OpenMP (user “defined”) • Long Wave CLIRAD• Atmophere-Ocean Coupled Model: latest version of AGCM

CPTEC/INPE and MON4. • 2 Steps Semi-Lagrangean Time Integration and Tracers• Boundary Layer Parameterisation (Hostlag e Boville, 1992)• Sib 2.5 (Sellers, 1996)• Dynamical Vegetation IBIS 2.6 (Foley et al, 1996)



Undergoing Developments• New Assimilation System LETKF: Maryland University• Improvements on CPTEC EPS: perturbation on humidity

and surface pressure, extension of the perturbation area to middle latitudes, stochastics perturbations on the tendencies of physical process, lagged forecast using 00 and 12 UTC runs, moving to members defined by LEKF Assimilation System.

• Chemistry from BRAMS• Observed Initial Condition for Snow• Leaf 3.0 From BRAMS• New Shallow Convection (based on Souza, 1999)• Arakawa & Schubert Convection



Paralel Computational Performance of the Latest VersionParalel Computational Performance of the Latest Version

Eulerian Time Integration with Reduced Quadratic GridEulerian Time Integration with Reduced Quadratic Grid

NEC/Sun Cluster Run



Near Future Plan:• Community Global Model

Future Plan:• Global Model for Simulate Scenarios of Climate

Changes



Thank You

the brazilian effort on the global model

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