Improving seismic remote sensing of typhoon with a three-dimensional Earth model

Area of Science:

• Geophysics
• Seismology
• Oceanography

Background:

• Typhoon-induced P-wave microseisms offer insights into seismic monitoring of ocean storms.
• Existing methods often rely on simplified one-dimensional (1-D) Earth models.

Purpose of the Study:

• To introduce and validate a frequency-domain beamforming (FB) method incorporating a three-dimensional (3-D) Earth model for improved microseism source localization.
• To assess the accuracy enhancement provided by a 3-D model over a 1-D model in seismic storm monitoring.

Main Methods:

• Development of a frequency-domain beamforming (FB) technique integrating a 3-D Earth model.
• Application of the FB method to seismic data from Super Typhoon Lupit (2009) using NECESSArray and Hi-net observations.
• Comparative analysis of source localization accuracy using 3-D versus 1-D Earth models.

Main Results:

• Localized P-wave microseism source regions using the 3-D model showed better agreement with theoretical sources and typhoon centers.
• The 3-D model resulted in more consistent and mutually concordant source localization results between different seismic arrays.
• Integration of the 3-D model significantly improved the accuracy of locating typhoon-induced P-wave microseism sources.

Conclusions:

• The proposed FB method with a 3-D Earth model enhances the precision of seismic monitoring for ocean storms.
• Utilizing 3-D subsurface heterogeneity information is crucial for accurate ray-tracing and travel-time predictions in microseism analysis.
• This advanced approach provides more reliable data for understanding and tracking typhoons through seismic observations.