Development of Advanced Propagation Models and Application to the Study of Impulsive Infrasonic Events

摘要

Research advances have been made in the areas of advanced model development, ground truth (GT) event studies, and model validation. They are focused on understanding the driving mechanisms that affect measured waveforms, and quantifying the prediction performance of new modeling capabilities. High fidelity predictions of infrasonic waveforms properties, including travel time and amplitude, improve source localization. These advances also support discrimination between various infrasonic impulsive events. New additions have been made to the GT database. These additions mainly focus on events that are directly related to nuclear weapons testing: near-surface nuclear explosion (NE), underground nuclear explosion (UNE), and high-explosives (HE) events. They are well-calibrated GT events and significant domain knowledge resides with our Los Alamos National Laboratory (LANL) colleagues. Digital waveforms from the HE events at range of 1.5 to 60 km have been acquired and will be used to explore the boundaries between propagation regimes near the infrasound source. New propagation modeling capabilities include a ray model that incorporates the effects of diffraction, PE/TDPE models that incorporate small- scale atmospheric variability, and PE/TDPE models that account for terrain. Detailed model comparisons studies have been complete for both the 1988 Henderson explosion and White Sands Missile Range (WSMR) I, II, and III rocket experiments.