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HIRLAM Use of the Hirlam NWP Model at Met Éireann (Irish Meteorological Service) (James Hamilton -- Met Éireann). COMPUTER SYSTEM and VERSIONS of HIRLAM IBM RS/6000 SP : 9-nodes each with 4-CPU’s Operational Hirlam : 438x284 grid pts; 31-levels Nested Hirlam : 222x210 grid pts; 40-levels - PowerPoint PPT Presentation
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HIRLAM
Use of the Hirlam NWP Model
at Met Éireann (Irish Meteorological Service)
(James Hamilton -- Met Éireann)
COMPUTER SYSTEM and VERSIONS of HIRLAM
IBM RS/6000 SP : 9-nodes each with 4-CPU’s
• Operational Hirlam : 438x284 grid pts; 31-levels
• Nested Hirlam : 222x210 grid pts; 40-levels
LINUX PC : Twin Xeon Processors [2.0Ghz]
• Backup Hirlam : 218x144; 31-levels
LINUX PC : Twin Xeon Processors [500Mhz]
• Hourly Hirlam : 97x98 grid pts; 24-levels
LINUX Cluster : Nine Twin Xenon Processors [3.2GHz]
•Operational Hirlam : Test mode
OPERATIONAL HIRLAM … IBM RS/6000 SP
HIRLAM 5.0.1 with 3DVAR
• 3-Hour assimilation cycle with 48-hour forecasts every 6-hours
• Rotated lat/long 0.15x0.15 grid with 438x284 grid points
• Hybrid [eta] coordinates with 31-levels
• CBR vertical diffusion scheme; Sundqvist condensation scheme
• STRACO cloud scheme; Savijarvi radiation scheme
• Digital filter initialisation
• Two time-level Semi-Lagrangian semi-implicit scheme
• Use of ‘frame’ boundaries from ECMWF
BACKUP HIRLAM … LINUX-PC [Dual 2.0Ghz CPU]
HIRLAM 4.3.5 with OI-Analysis
• 3-Hour assimilation cycle with 48-hour forecasts every 6-hours
• Rotated lat/long 0.30x0.30 grid with 218x144 grid points
• Hybrid [eta] coordinates with 31-levels
SAME AREA AS OPERATIONAL HIRLAM
NESTED HIRLAM … IBM RS/6000 SP
HIRLAM 6.0.0 with 3DVAR
• 3-Hour assimilation cycle with 24-hour forecasts every 6-hours
• Model runs at intermediate hours … 03Z, 09Z, 15Z, 21Z
• Rotated lat/long 0.12x0.12 grid with 222x210 grid points
• Hybrid [eta] coordinates with 40-levels
• Kain-Fritsch/Rasch-Kristjansson convection/condensation scheme
• ISBA surface scheme
• Output post-processed with MOS
HOURLY HIRLAM ... LINUX-PC [Dual 500Mhz CPU]
HIRLAM 4.3 with OI Analysis
• Hourly assimilation cycle with hourly analysis and 3-hour forecast
• Rotated lat/long 0.15x0.15 grid with 97x98 grid points
• Hybrid [eta] coordinates with 24-levels
• Analysis shown on public web-site
OPERATIONAL USES of HIRLAM
General Forecasting
• Forecast guidance out to 48-hours
WAM wave model
• Forecast 10-metre winds used to drive model
Roadice Prediction System
• Forecast parameters are used as first guess for [human] forecaster
SATREP
• Overlay on satellite plots [ZAMG SATREP analysis scheme]
RESEARCH ACTIVITIES
Better Specification of B.C.’s for NWP models
Operational Implementation of Nested System
Regional Climate Analysis Modelling & Prediction Centre
Community Climate Change Consortium for Ireland
[RCAMPC and C4I]
EXPERIMENTS with LINUX CLUSTER …
Purchased small experimental Linux-Cluster
• Dell PowerEdge 1750 Twin Xeon nodes – rack mounted
• 1 x Master node [2.8GHz, 4Gbytes]
• 9 x Compute nodes [3.2GHz, 2Gbytes]
• Compute nodes in 3x3 2-dimensional torus [Dolphin cards]
• RedHat ES-3/WS-3; PGI compilers; Intel compilers
• Scali MPI connect, Scali TCP connect, Scali Manage
• Original cluster had 6-nodes : upgraded to 9-nodes
EXPERIMENTS with LINUX CLUSTER …
Running Operational Hirlam on Cluster [9-node]
• Hirlam 5.0.1 with 3DVAR – identical to operational system
• Forecast takes 62 mins on IBM/SP; 71 mins on cluster
• 3DVAR takes 15 mins on IBM/SP; 9 mins on cluster
• Full run takes 77 mins on IBM/SP; 80mins on cluster
• Therefore … 9-node cluster is as fast as IBM/SP
Experience with Cluster Generally Positive
FUTURE PLANS for CLUSTER ….
Investigate Use of Intel Compilers and Libraries
• Should be faster for running Hirlam
Use Cluster as test-bed to implement latest Hirlam 6.4
Use Cluster to prepare benchmark for new mainframe
Replace Mainframe end of 2006 / start of 2007
FUTURE PLANS …
Investigate Options to Replace Mainframe in 2006
Get Hirlam 6.4 Running on Cluster
Investigate MOS/Neural-Nets for Post-Processing
Use Hirlam as input to Point Data-Base
Thank You