Parallelizing a global atmospheric chemical tracer model

We describe the design of a parallel global atmospheric chemical tracer model. This is part of a larger Earth Systems Model (ESM) for atmospheric dynamics and physics, and ocean physics. The ESM will be used for global warming and ozone depletion studies, among others. The goal is to parallelize the chemistry model to run efficiently on current and future parallel architectures, including the Sequoia archival database. We describe the preliminary design, especially the detailed timing model, and some initial validations. We have found a timing modeling very valuable for designing for a large range of architectures