The Canadian Numerical Weather Prediction System: Present and Future

Gilbert BrunetRecherche en Prévision Numérique (RPN)Meteorological Research BranchMeteorological Service of CanadaEnvironment CanadaQuébec, Canada

Thursday, November 1, 2001, CAS 2001 meeting, Annecy, France

Introduction

The main mandate of the Meteorological Research Branch (MRB) is to improve the operational Numerical Weather Prediction (NWP) and data assimilation system at the Canadian Meteorological Center (CMC) of the Meteorological Service of Canada (MSC)

We have to integrate in the NWP system observation instrument systems that has a maximum impact on improving prediction skill, like satellites, and radar for very-short-range forecasts

Environmental Prediction: We have to couple our NWP system with ocean, hydrological and chemistry models

RPN - Recherche en Prévision NumériqueMany major world-wide innovations During 1960’s and 1970’s Semi-implicit method, Robert-Kwizak First integration of spectral model, Robert Optimum Interpolation, Rutherford Operational spectral model, Daley-Girard Finite Element model, Staniforth-Daley During 1980’s and 1990’s Semi-Lagrangian technique, Robert et al. First operational TKE PBL, Benoit et al. Ultra-fast FFT’s (Cray,CDC), Temperton First SI-SL fully non-hydrostatic model Tanguay, Laprise , Robert (later MC2) Unified GEM (global, uniform or variable resolution), Staniforth, Côté, Gravel et al. MC2 is internationally recognized for mesoscale modeling, Benoit et al.

Increasing computer power Increasing computer power

1960 ’s - Bendix G20, IBM370. 1970’s: Control Data 7600, Control Data 176 1980’s: Cray 1S, Cray XMP-2/8, Cray XMP-4/16 1990’s: NEC SX-3/44, SX-3/44R, SX-4/64M2 and SX-5/32M2 2000’s: Requirement for a new contract & new HPC systems

SGIO2000's28 PEs

(MIPS R10K)10x FC

dualattach

1.2TB

Front Ends

2x ea

7x ea.

Supercomputing Cluster

HIPPIRAIDs

(0.8 TB)

24x

HIPPI 1000 Mb/s switched128 ports. Each host haslinks to ops & dev networks

Central File Server

IXS (8GB/s)

NECSX-4/64M2

FC switched 32 ports

IXS (16 GB/s)

NECSX-5/32M2

0.7 TB RAID

Climate Archive

1.2 TB14x SCSIfrom OSS

O2000 4 xR10K PEs

145 TB4 DST drives20 MB/s ea.

SGI O2000: 4 PEs

ADIC AML-E (Tape Robot)0.7 TB4xFC

Max StratGen5RAID

Trend in skill 1958-2000

Different problems need different modeling approaches and physics

ONGOING RESEARCH at RPN (in collaboration with Canadian and International Institutions)

Global predictions need an uniform space grid model with a good climatic balance between dynamics and physics (Collaboration with CCMA/Victoria)

Regional predictions need a variable space grid model with improved implicit physics, like Kain-Fritsch deep convection scheme

(Collaboration with McGill U. and Cloud Physics/SMC,Toronto)

Montainous and high resolution predictions of precipitation need a non-hydrostatic and limited area

model with explicit physics, like Kong-Yau. (Collaboration with Mesoscale Alpine Project (MAP),

McGill U. ) Environmental prediction needs to couple the NWP system with hydrology , and ocean, and

chemistry and wave models. (Collaboration with York U., Dalhousie U., Waterloo U., McGill U., Atlantic and Ontario SMC/Regions and Canadian Space Agency)

Middle atmosphere capability for integrating Canadian space and ground-based measurements and chemical modelling activities, like ozone (Collaboration with York U. and Canadian Space Agency)

Multi-seasonal forecasting needs a low resolution model with a particular attention to surface forcing, like sea temperature and soil moisture (Collaboration with CCMA/Victoria and McGill U.)

Different problems need different modeling approaches and physics

Variational data assimilation, 3Dvar and 4Dvar, needs the development of highly sophisticated numerical tools that are tied closely to the model dynamics and physics

Adaptation to new computer architecture is highly model dependant.

Global Environmental Multiscale (GEM): An integrating concept, one tool for different problems.

Leader: J. Côté and S. Gravel

Global Environmental Multiscale Forecasting & Modeling System2001-2006

Regional andMesoscale Forecast( 24-48 h 10-24 km )

&Data assimilation

Medium-range Forecast( 240 h 35-100 km )

&Data assimilation

Middle Atmosphere Model&

Data assimilation

Regional Climate Model

Monthly Forecast

Multi- Seasonal Forecast

Ensemble Forecast

Limited-area Environmental Multiscale Model0-24h 1-4km

Uniform resolution Variable resolution Hydrostatic Nonhydrostatic Global Limited-area Distributed memory--------------------------------- 3D Var Data Assimilation 4D Var Data Assimilation Operational forecast Emergency response Volcanic ashes Air quality Stratospheric ozone Wave model Coupling to Hydrology Coupling to Oceanology Simulations etc

SPACE

SCALE

TIME SCALE

Physical Processes Leader: S. Bélair and J. Mailhot

S. Bélair Surface Processes

HEM

G

SolarRadiation

InfraredRadiation

Boundary-Layer Turbulence

DeepConvection

Stratiform Precipitation

Physics (2000-2005) Global model with a 35km resolution with an

optimized Kain-Fritsch, Tremblay (Cloud Physics/SMC) phase mixed scheme and ISBA surface scheme that drives a continuous data assimilation cycle

Regional model with an optimized Kain-Fritsch and Tremblay (Cloud Physics/SMC) phase mixed scheme with a 10km resolution that drives a continuous data assimilation cycle

Non-hydrostatic modeling of a severe weather squall line in Oklahoma

Radar reflectivity of the squall line event

Cloud water/ice

Cloud water/iceHydrostatic Non-Hydrostatic

Non-hydrostatic effect: importantfor timing?

Regional GEM Model (rough estimates for research)

Application: Regional GEM Model

2000/2001 2002/2003 2005/2006Configuration: 20Km-L35-48Hr 10Km-L60-48Hr 10Km-L60-48HrTime to complete application (hrs) 0.75 1 1Runs per week 30 30 30Concurrent (simultaneous) runs 1 1 1Number of ensemble members 1 1 1

Number of FLOPS (PetaFlops) 0.046 1.48 1.6Memory needed (GB) 7.3 50 50Volume of files archived (GB) 1.1 7.5 7.5

GLOBAL GEM GRID AT 35km

An 35km global uniform resolution GEM with an improved physics and cloud package for the Meteorological Service of Canada

Model Results

A

B

C

SAT(OBS)

OP

NEW

SAT(OBS)

SAT(OBS)

OP

OP

NEW

NEW

Outgoing longwaveradiation for a 1-dayforecast valid at 0000UTC 2 November 2000 using the proposed high-resolution modelconfiguration

A) Mid-latitude synoptic-scale systems over North America: Better representation of cold frontal convection and of occluded cyclonic circulationsB) Convective activity over South America: More widespread continental convective activity and better representation of low- level cloudsC) InterTropical Convergence Zone: Better representation of convective activity and of a Typhoon over southeast Asia

A

B

C

Global GEM Model (rough estimates for research)

4DVAR GEM Global Model (rough estimates for research)

Application: 4DVAR Global GEM Model

2000/2001 2002/2003 2005/2006

Configuration: 50Km-L35-120Hr 35Km-L60-240Hr 18Km-L70-240HrTime to complete application (hrs) 24 24 24Runs per week 0.5 2 5Concurrent (simultaneous) runs 1 1 1Number of ensemble members 1 1 1

Number of FLOPS (PetaFlops) 0.85 37.5 350Memory needed (GB) 27 45 175Volume of files archived (GB) 15 230 930

Community Of Mesoscale Modeling(COMM) group Leader: R. Benoit

Community model (MC2) support is essential in order to partner effectively with universities and benefit from funds provided through Canadian Foundation Climate and Atmospheric Science ($10 000 000 per year)

Community model would be configured to focus on region with potential active or extreme weather events at 1-3km horizontal resolution.

MC2 is worldwide recognized as one of the most computer efficient non-hydrostatic model

MC2 run at 2km horizontal resolution over Vancouver Island 17H forecast valid 26 June 1997 2000 UTC. Near surface flow (arrows with scale in knots in lower left corner). Superimposed over topography (gray shades every 500m). Only one arrow every other grid point for each directions is displayed.(M. Desgagné)

Configuration: 1500 x 1300 x 31; 2880 time steps of 30 sec (24H); 14 PEs SX5; total memory: 46 Gb, wall clock : 16 H, Flops rate : 29 Gflops

Limited-Area GEM Model for high resolution meteorology (2000km X 2000km)(rough estimates for research)

Application: High Res. Meteorology

2000/2001 2002/2003 2005/2006

Configuration: 2km L80 24H 1km L80 12H 1km L80 12HTime to complete application (hrs) 48 24 12Runs per week 0.5 1 2Concurrent (simultaneous) runs 1 1 1Number of ensemble members 1 1 1

Number of FLOPS (PetaFlops) 7.52 19.5 19.5Memory needed (GB) 52 70 70Volume of files archived (GB) 8 11 11Peak GFLOPS/S 28 463 463

Coupled Modeling for Environmental PredictionLeader: H. Ritchie

RPN Environmental Prediction and Coupled Modeling

group is supporting/conducting R&D based on coupling

a variety of numerical prediction models

Now feasible due to advances in numerical modeling

in various domains, together with advances in

computer power.

Very high level of collaboration with international and Canadian

university and institutions. We are the provider of the numerical

modeling and computer expertise

High potential for Canadian Foundation for Climate and Atmospheric

Science collaborations

Key projects Atmosphere-hydrology Model (Waterloo U., IML, MAP, Ontario/MSC

Region, …) Regional Ocean Modeling and Prediction (Dalhousie U., BIO,IML,...) 3-D ocean circulation models being coupled with MSC models for

atmosphere-ocean prediction (Dr. Greatbatch, Dalhousie U.,...) Coastal Modelling Systems for Storm surge forecasts (Atlantic/MSC region,

Dr. Thompson, Dalhousie U.,...) Atmosphere-wave Modeling (Atlantic/MSC Region,...) St. Lawrence Estuary Models (IML) Marine Environmental Prediction System: Coupled

atmosphere/ocean/biology/chemistry ecosystem model to be developed for demonstration site for Lunenburg Bay, NS (Dalhousie U., Bedford Institute of Oceanography,...)

Extra-tropical hurricane transition (Dalhousie U., McGill U., ...)

26

Marine Environmental Prediction System (MEPS) To establish demonstration site for Lunenburg

Bay, NS.

Goal: interdisciplinary marine environmental prediction guided and tested using advanced observing systems.

Coupled atmosphere/ocean/biology/chemistry ecosystem model being developed.

The Dream

The Reality

Extratropical Transition- Examining mid latitude transition of hurricanes and typhoons.- Eventually to use two-way interactive atmosphere-ocean data assimilation and prediction system for direct modeling.

ED

FLO

10km/60 levels Kuosym/Sundqvist (MC2, M. Desgagné) 24-72 H Forecast of relative vorticity at 25m (frame every hour) COMPARE

2km/40 levels Kong&Yau (MC2, M. Desgagné)16-30 H Forecast of Relative Vorticity at 20m (frame every hour) COMPARE

Limited-Area GEM Model for high resolution meteorology (2000km X 2000km)(rough estimates for research)

2000/2001 2003/2004 2006/2007

Configuration: 4km L35 48H 2km L80 24H 2km L80 24HTime to complete application (hrs) 6 6 6Runs per week 5 2 4Concurrent (simultaneous) runs 1 1 1Number of ensemble members 1 1 1

Number of FLOPS (PetaFlops) 0.6 10 10Memory needed (GB) 8 70 70Volume of files archived (GB) 2 8 8Peak GFLOPS/S 28 463 463

Conclusion Meteorological Research Branch used in general 40% of the computer resources Climate Research Branch used in general 40% of the computer resources Canadian Meteorological Center used in general 20% of the computer resources

For (2001-2006) the R&D strategy

Global NWP with a MESOGLOBAL GEM (35km) with a lid at the stratopause (1mb) with the Regional GEM physics package

Global NWP ensemble forecast with GEM-100km with an improved physics package

Collaborating with CFCAS to improved our Regional and Local NWP Collaborating with CFCAS and other partners for Environmental Prediction

(coupling with chemistry, hydrology and ocean)