1. Summary of 2003 Infrasound Technology Workshop
Session Chairs

2. IMS Network/IDC Processing
Rapid growth of IMS network: 23 transmitting, 13 certified, 12 under construction
IDC Testbed: 16 current
IDC Operations: 11 current
Infrasound temporarily out of SHI data fusion process
High number of detections
Large scale automatic processing in November 2003
Progress in modeling network performance: incorporation of seasonal variance

3. New Developments Experimentation with new array configurations
Noise filtering at extreme wind (> 40m/s)
Monitoring of volcanic eruptions and hurricanes
Improved characterization of specific heat ratio of the atmosphere up to heights of 160 km
Improvement of ANSII standard for attenuation coefficient at low frequencies and high altitudes

4. New Developments GINA prototype is available to infrasound community
InfraMatics, AGU and AGU monograph
Progress in IIC: Collaborations are invited

5. Sources Discrimination between stationary and moving sources
Studies of bolides, eruptions, MAW, aurora, microbaroms, earthquakes, ice avalanches, surf, man-made signals
More work needed in detection, characterization, far and near-field location

6. Modeling Propagation modeling of signals from Columbia and explosions
Source modeling of microbaroms
Improvements in location and full wave modeling of infrasonic signals
Time-domain PE (broadband modeling)
Direct time-domain solutions of the wave equation
Use of improved atmospheric estimates
Need for implementation of improved absorption models

7. Processing Impact of noise levels on detection rate
Importance of using more accurate atmospheric models for source localization
Automatic associations, detection statistics, clutter rejection
Data sets assembled for ROC curve analysis
Studies of the relationship between array configuration/location and performance of detection and estimation algorithms
Correlation detectors effective and robust
Detection: recognize a signal is present - correlation detectors work well
Estimation: calculation of parameters that describe signal properties

8. Processing
4D location of atmospheric explosions using ground observations of acoustic waves.
GT data key to progress in location and characterization.
PMCC love fest
Deals well with different array geometries
Must be optimized to find particular signal features
Velocity model key. Use acoustic waves and acoustic coupled to seismic

9. Noise Reduction
Light-speed filters have obvious advantages over sound-speed filters but further research/engineering improvements required
Velocity model key. Use acoustic waves and acoustic coupled to seismic

10. Conclusions
Continue to probe at basic, difficult but key, aspects of acoustic source phenomenology, propagation, modeling and reception
Data processing must continue to advance rapidly to deal with mushrooming data volume
Research community continues to make great progress in array design
Essential that these results are used to optimize existing or new IMS stations
Velocity model key. Use acoustic waves and acoustic coupled to seismic