An atmospheric transport model, FRAME (Fine Resolution AMmonia Exchange), has been used to model the spatial pattern of ammonia concentrations and deposition over the British Isles for the first time. The model uses a multi-layer approach with diffusion through 33 layers to describe vertical concentration profiles in the atmosphere explicitly. Together with the necessary description of atmospheric reactions with sulphur and oxidised nitrogen, this imposes a major computational requirement, with the model having a run-time of 8.5 days on a mid-range workstation. Improvement in the model run-time was sought by developing a parallel implementation coded in a data-parallel approach using High Performance Fortran. Running the code on a Cray T 3E with 128 processors provided a speedup by a factor of 69. The code's portability, its validation with measurements and new maps of its application to the British Isles, are presented. Good agreement is found with measured NH3concentrations, while wet de-position is underestimated. In addition to model uncertainties, this may be due to an underestimation of the NH3emissions input data. © 2001 Elsevier Science Ltd. All rights reserved.
All Science Journal Classification (ASJC) codes
- Health, Toxicology and Mutagenesis
Fournier, N., Pais, V. A., Sutton, M. A., Weston, K. J., Dragosits, U., Tang, S. Y., & Aherne, J. (2002). Parallelisation and application of a multi-layer atmospheric transport model to quantify dispersion and deposition of ammonia over the British Isles. Environmental Pollution, 116(1), 95 - 107. https://doi.org/10.1016/S0269-7491(01)00146-4