Overview of the InfraMAP Tool Kit and Related Propagation Modeling Technologies

1. Overview of the InfraMAP Tool Kit and Related Propagation Modeling Technologies Robert Gibson and David Norris BBN Technologies Arlington, VA 2nd NSF Infrasound Workshop, Stevenson WA 8 June 2005

2. Agenda • InfraMAP Tool Kit • Recent Propagation Modeling Developments • Example studies

3. InfraMAP Overview • InfraMAP - Infrasonic Modeling of Atmospheric Propagation • Designed for researchers and analysts active in the infrasound community • Supports infrasonic-relevant R&D and can be applied to specific source mechanisms and propagation paths of interest • InfraMAP is a software toolkit • menu interface built with MATLAB GUIs • link to FORTRAN and C program executables • integrates propagation and environmental models to perform infrasound studies • BBN is continuing to enhance the capabilities of InfraMAP and are experts at applying it to the study of complex infrasonic problems

4. Environmental Analysis • Empirical characterizations are built-in • Near-real-time characterizations can be imported • View Environment functions via GUI • Seamless integration with propagation models

5. Propagation Analysis 3-D Ray Tracing Normal Modes Parabolic Equation

6. Variability Analysis

7. IS26 IS10 NVIAR Baseline localization DLIAR Model-enhanced localization IS57 Source IS59 Ground Truth Localization Analysis

8. Time-Domain PE • Waveform prediction capability • Accounts for refraction and diffraction • Examples of TDPE model output shown

9. TPDE waveform predictions for bolide • Time-domain Parabolic Equation (TDPE) model (broadband, complex boundary conditions, range-dependent environment) • Bolide over El Paso, TX, USA, observed 09 Oct 1997 at TXIAR station 359 km away • Source height estimated to be 29 km • TDPE broadband prediction, 0 – 2 Hz. • 3 dominant arrivals predicted. Mismatch for early and late arrival Observation TDPE Prediction over all receiver heights TDPE Prediction at ground

10. Infrasound Propagation Modeling using Near-Real-Time Environmental Updates Mesoscale Atmospheric Characterization: COAMPS • InfraMAP can import near-real-time atmospheric characterizations for use with propagation models • NRL-G2S semi-empirical specification • Global spectral representation • NOGAPS numerical weather prediction model • To ~35 km, merged with climatology above • Mesoscale characterizations, e.g., COAMPS, will be integrated • Figures below show zonal winds (0-50 km) over a path from Cape Kennedy, FL to I10CA • Fine-scale structure in near-real-time grids Climatology NRL-G2S NOGAPS

11. Explosive eruption 2001-July-29 ~0600 GMT Observed at Deelen, NL and elsewhere in Europe Ground truth from Deelen: ~1750 km 152.4 degrees Observed azimuth of arrival 156 degrees +3.6 degrees of azimuth deviation Data analysis by L. Evers (KNMI) Predicted azimuth using InfraMAP 156.4 degrees Thermospheric paths Using empirical atmospheric models Etna Eruption

12. Lac du Bonnet, (IS10) Los Alamos Blossom Pt. Shuttle Trajectory Cape Kennedy Observations of Space Shuttle Launches

13. Space Shuttle Columbia Disaster Analysis • Conducted for DoD, to assist NASA investigation. Trajectory - (white) Arrays - (red) CPA’s - (yellow) Good agreement between data (Δ’s) and models Example: Results for Pinon Flat, CA Array Azimuth (deg) Time (GMT)

14. InfraMAP Objectives • Integrate the software tools needed to perform infrasound propagation modeling. • Define the state of the atmosphere (temperature, wind) as required for input to propagation models. • Predict phases (travel times, bearings, amplitudes) from atmospheric explosions as measured by infrasound sensors. • Apply tools to support nuclear explosion monitoring R&D and resolve operational issues: • environmental variability and propagation sensitivity • prediction of localization area of uncertainty and detection performance • performance model of an infrasound network • Interfaces, models and algorithms are readily applicable to scientific investigations.