DOBSON: a Pentium-based SMP Linux PC Beowulf for distributed-memory high resolution environment modelling

With the increasing computational speed of PC processors, lowering hardware prices, and the increasing accessibility of open source software, PC clusters have become an attractive option for exploring budgetary high performance computation on high resolution environment modelling. This paper documents the implementation and operation of a Beowulf-class PC cluster called DOBSON built in the Atmospheric Modelling Laboratory at National Central University in Taiwan. Based on our current configuration, the DOBSON cluster achieves a 4.4-8.7 times of speedup with 8 and 14 CPUs, respectively, compared with a 1 CPU in simulations of the Antarctic vortex. The potential impacts of running a high resolution environmental modelling system on the DOBSON cluster were examined by case simulations of Typhoon Haiyan with a nested five-domain configuration. These results show that the complicated topographical flow in the Taipei Basin can only be properly resolved when model grid resolutions less than 9 km were used.