Infrasound from Bolides

1. Infrasound from Bolides Meteor research showed a mature integration of imaging, radar, and infrasound technologies in an automated operational system, allowing a better statistical assessment of bolide detections and physical parameters. There appears to be substantial improvements in source models, with an introduction of a quasi-ballistic component of the radiated sound field. There seems to be a higher bolide incidence rate and a lower detection threshold than previously anticipated. New neural network implementations may help optimize the detection and recognition of meteor events. There appears to be good agreement between theory and observations up to 100g for size and speed of meteors. Revisited historical events for larger bolides and validated and refined previous yield relationships. The compelling evidence provided by the falling cyclist, the unbroken shed, the bull with a broken horn, and the standing man incriminated the rapidly falling rock. Infrasound recordings provided the essential evidence to seal the case. The remarkable survival of the rock upon entry remains exceptional, and may shed insight into similar cases in the outer planets. Different methods has been applied, provide similar results. Infrasound Technology Workshop, BermudaSection 6. Infrasound from Geophysical SourcesChairs: Milton Garces and Alexis Le Pichon

2. Infrasound Technology Workshop, BermudaSection 6. Infrasound from Geophysical SourcesChairs: Milton Garces and Alexis Le Pichon The 2008TC3 Sudan bolide, although not exceptional in size and yield, is the first predicted bolide impact. Lot of observations. Provides a unique and unprecedented ground truth event for yield relations. Many interesting presentations demonstrating the potential of a continuous infrasound monitoring. The IMS network has multiple geophysical applications for the monitoring of volcanic eruptions, severe weather, bolides, and mass wasting. Microbarom signals may provide a useful tool for the passive acoustic tomography of the atmosphere, and may contribute to monitoring climate change at global scales. Monitoring gravity waves may also provide useful information on the atmospheric dynamics. The acoustic remote sensing of volcanic eruptions with IMS and regional networks has progressed substantially. The growing number of stations is allowing a greater collection of case studies of large eruptions that inject ash into the stratosphere. Preliminary results suggest that the eruption onset time, duration, and ash height probability of large eruptions may be reliably inferred from infrasound data.