MODELING THE IONOSPHERIC SIGNATURES OF GEOMAGNETIC-PULSATIONS

Oscillating phase shifts are frequently observed in ionospherically propagated HF radio waves in association with ULF geomagnetic pulsations. These Ionospheric Signatures of Pulsations (ISP) are observed in ionospherically reflected radio waves transmitted from ground stations, in radio signals transmitted from satellites to ground stations, and in the backscattered signals received by HF over-the-horizon radars. We review the techniques used to model the relationship between ISPs and geomagnetic pulsations. Model results for a variety of geophysical conditions are compared with observations.