BREEZE AERMOD Parallel Tech Sheet

The input meteorological data requirements and technicalenhancements incorporated in AERMOD, the U.S. EPA approvedrefined air dispersion model for most modeling applications,cause model runs to take significantly longer as compared to thepredecessor regulatory model ISCST. In order to address thisissue, BREEZE offers AERMOD Parallel, a version designed tominimize runtimes through the use of a distributed computernetwork (cluster) or multi-CPU environment.Same Results, Faster Run-TimesBREEZE AERMOD Parallel produces pollutant concentrationestimates identical to EPA’s Fortran executable. The only codechanges contained in the product are additions to implement theparallel features. The product runs the exact algorithms but ondifferent processors. Improvements in the product’s performanceenhancements are based directly on the number of CPUs (or BREEZE® AERMOD Parallelcores) utilized. Furthermore, it accepts AERMOD input files created for use with any version of EPA’s AERMOD and is available in both Windows and Linux versions. When purchasing AERMOD Parallel, users also receive a parallelversion of AERMAP, the AERMOD terrain preprocessor. Thisfunctionality further expedites run times by speeding thecomputation of receptor elevations and effective height scalesfor numerous types of digital terrain formats.How it WorksLicensing for BREEZE AERMOD Parallel is based on how manyCPUs/cores and computers will be used to run the application,from a single computer with a dual core CPU to a network ofdual (or greater) core computers. The efficiency gains associatedwith using AERMOD Parallel are largely dependent upon thehardware configuration and illustrated in the table below. EPA Serial BREEZE Parallel Improvement (h:m:s) (h:m:s) (%)AERMOD39 area sources; 2921 gridded receptors 19:15:00 9:30:00 203Dual core, 1.83 GHz processors with 2 Gb RAM16 point sources; 22500 gridded receptors 8:37:50 3:53:02 222Dual core, 1.83 GHz processors with 2 Gb RAM39 area sources; 2921 gridded receptors 39:09:00 9:42:00 403Dual processors with hyperthreading2.2 GHz processors with 2 Gb RAM6 circle area sources; 2500 gridded receptors 1:41:02 0:44:51 225Dual core, 1.83 GHz processors with 2 Gb RAM6 polygon area sources; 1600 gridded receptors 2:07:46 0:56:33 226Dual core, 1.83 GHz processors with 2 Gb RAM6 volume point sources; 2500 gridded receptors 0:15:29 0:6:59 222Dual core, 1.83 GHz processors with 2 Gb RAMAERMAP14743 receptors in 2 DEM file 01:17:52 0:32:10 242Dual processors with hyperthreading2.2 GHz processors with 2 Gb RAM2602 receptors in 1 DEM file 0:15:36 0:09:11 170Dual core, 3.2 GHz processors with 3 Gb RAMScenariosAERMOD Runtime Comparisons(972) 661-8881 ¦ Fax: (972) 385-9203breeze-software.com ¦ [email protected]