Optical and Radio Remote Sensing of Space Plasma Turbulence
2008
Lee, Min-Chang
Experiments were conducted at Arecibo, Puerto Rico to investigate naturally-occurring and radio wave-induced ionospheric plasma turbulence. The intriguing phenomena reported here include large-scale turbulence created by tsunami-launched gravity waves [Lee et al., J. Geophys. Res., 2008] and short-scale turbulence generated by VLF waves from the Navy transmitter (code-named NAU) in Puerto Rico [Labno et al., J. Geophys. Res., 2007]. Presented are ionospheric measurements using Arecibo 430 MHz radar supported by data from two ionosondes and GPS satellites. The M(w) = 9.2 earthquake in Sumatra, Indonesia on December 25, 2004 launched tsunami and then gravity waves first across the Indian, then into the Atlantic and Pacific Oceans, triggering intense ionospheric plasma turbulence over Arecibo. The NAU-generated waves are intense enough to excite lower hybrid waves, which can accelerate electrons continuously along the geomagnetic filed, to cause enhanced plasma lines detected by Arecibo radar in the nighttime ionosphere F region in the presence of spread F events. These energetic streaming electrons, when detected by the Arecibo 430 MHz radar, give rise to enhanced plasma lines with a frequency spectrum of approximately 3.25 - 4.75 MHz.
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