Atmospheric or meteorological condition is one of the most influential environmental factor in outdoor sound propagation. Yet it is also one the most difficult to characterise because of its variability with time and space. Sophisticated monitoring equipment such as radio-sonde, acoustically based SODAR or optically based LIDAR can be used to scan the atmosphere but they are generally not readily available for outdoor sound measurements in practice. Instead typical meteorological monitoring in a typical acoustic field trial uses a single wind mast to measure wind and temperature data at two heights. It is then common practice to simulate sound speed profile and turbulence parameters from these measurements to represent the meteorological condition over the entire propagation path. In this paper a set of meteorological and sound propagation data measured at three sites of different terrain features over several weeks is examined to look at the correlation between the meteorological and acoustic data. The meteorological data were measured by a wind mast near the source at two heights. Wind speeds measured covers both upwind and downwind conditions up to 10m/s. Prediction accuracy of sound propagation using these meteorological data by means of standard procedures and a heuristic ray tracing procedure is also investigated. It was found that the sound speed profile cannot be simulated by taking the simple difference between the data measured at two height. A sonic profile simulated by a simple logarithmic fit produces better results but the prediction accuracy is affected by high wind noise and uncertainties in the complex sites.
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