Microbarom Source Strengths from Spectral Ocean Surface Wave Models

This study describes the methods used to model the ocean surface wave field to represent acoustic signals generated by hurricanes and severe weather. To accurately reproduce the wave fields induced by hurricanes, the wind field must be adequately represented. This is accomplished by utilizing two models: a parametric hurricane model to recreate the wind field and a third-generation spectral wave model to recreate the ocean wave field. The parametric wind field is blended with the NCEP FNL reanalysis wind field to include background meteorological conditions. These data are then used to force the wave model to recreate the event. To validate this procedure, the simulated waves are compared with buoy observations. Finally, time-dependent theoretical microbarom and microseism source energy levels and distributions are estimated from spectral ocean surface wave models, and comparisons are made with infrasonic observations for selected case studies.