Resonant Cavities and Waveguides in the Ionosphere and Atmosphere

  title={Resonant Cavities and Waveguides in the Ionosphere and Atmosphere},
  author={Robert L. Lysak and Akimasa Yoshikawa},
  journal={Geophysical monograph},
The strong inhomogeneities in plasma parameters in the ionosphere and adjacent regions can trap waves in the upper end of the ULF range (Pcl/Pil). The topside ionosphere is characterized by a rapidly increasing Alfven speed with a scale height on the order of 1000 km. Shear-mode Alfven waves in this region can be partially trapped at frequencies in the 0.1-1.0 Hz range. The same structure can trap fast-mode compressional waves in this frequency band. Since these waves can propagate across… Expand

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