Field Measurement of Gas Dispersion in the Atsugi Area

The ability to predict the dispersion of gases is highly important for the environmental assessment of cities and industrial areas, where gaseous emissions have become a matter of global concern. Our study aims to understand the extent to which theoretical models of gaseous dispersion make accurate predictions when compared to actual measurements from real-world geographical areas and to investigate its limitations. With this in mind, we conducted a field study on gas dispersion in the urban area of Atsugi city in Japan. The release point for the gas was set on the rooftop of a building. The sampling points were located on the ground. We compared the distribution of dispersed gases in terms of concentration obtained from the field measurements with our calculations based on the plume model. Both sets of results were in good agreement with each other, except when there was atmospheric instability in an area where dispersion was measured. Meteorological parameters of wind direction fluctuation and vertical wind profile were studied to further understand the areas of atmospheric instability.