A performance comparison of atmospheric dispersion models over complex topography

A code system using mass-consistent and Gaussian puff model was improved for a new option of atmospheric dispersion research. There are several atmospheric dispersion models for radionuclides. Because different models have both merits and disadvantages, it is necessary to choose the model that is most suitable for the surface conditions of the estimated region while regarding the calculation time, accuracy, and purpose of the calculations being performed. Some models are less accurate when the topography is complex. It is important to understand the differences between the models for smooth and complex surfaces. In this study, the performances of the following four models were compared: (1) Gaussian plume model (2) Gaussian puff model (3) Mass-consistent wind fields and Gaussian puff model that was improved in this study from one presented in Aomori Energy Society of Japan, 2005 Fall Meeting, D21. (4) Meso-scale meteorological model (RAMS: The Regional Atmospheric Modeling System) and particle-type model (HYPACT: The RAMS Hybrid Particle and Concentration Transport Model) (Reference: ATMET). (author)