HPCN and air quality modeling

We discuss the implementation of an off-line air quality model (AQM). More precisely, how to design a code for an AQM that runs efficiently on a variety of computer platforms. We implemented our ideas in an AQM benchmark and we show the performance of this benchmark on the different architectural paradigms. A second subject of the paper is the I/O performance of the Cray~T3E for an off-line model. We implemented the required I/O in different ways and show that none of these results in a truly scalable I/O.