Traveltimes for infrasonic waves propagating in a stratified atmosphere

The Effects of Thermal and Wind Fields in the Propagation of Infrasonic Waves in the Atmosphere

Omar Marcillo Sound waves traveling at frequencies between 0.05 and 20 Hertz are called infrasound waves. Ocean waves, meteorites (Evers et al., 2001), large earthquakes, and volcanic eruptions (Johnson, 2003) are among the natural phenomena that produce infrasound waves. Nuclear and chemical explosions can also generate infrasound waves. Infrasound waves tend to travel long horizontal distance...

MHD mode conversion in a stratified atmosphere

Mode conversion in the region where the sound and Alfvén speeds are equal is a complex process, which has been studied both analytically and numerically, and has been seen in observations. In order to further the understanding of this process we set up a simple, onedimensional model, and examine wave propagation through this system using a combination of analytical and numerical techniques. Sim...

Apparent Attenuation of Shear Waves Propagating through a Randomly Stratified Anisotropic Medium

Waves propagating through heterogeneous media experience scattering that can convert a coherent pulse into small incoherent fluctuations. This may appear as attenuation for the transmitted front pulse. The classic O’Doherty-Anstey theory describes such a transformation for scalar waves in finely layered media. Recent observations for seismic waves in the earth suggest that this theory can expla...

Phase mixing of Alfvén waves in a stratified and radially diverging, open atmosphere

Phase mixing was proposed by Heyvaerts and Priest (1983) as a mechanism for heating the plasma in open magnetic field regions of coronal holes. Here the basic model is modified to include a gravitationally stratified density and a diverging background magnetic field. We present WKB solutions and use a numerical code to describe the effect of dissipation, stratification and divergence on phase m...

Sound propagation through and scattering by internal gravity waves in a stably stratified atmosphere