Evidence of kilometer-scale waves in the lower E region from high resolution VHF radar observations over Gadanki

摘要: [1] High resolution VHF radar observations made at Gadanki revealed the kilometer-scale waves in low latitude lower E region. These are found to occur a narrow altitude range of 92–97 km and have vertical wavelengths ∼0.5 wave periods ∼40 seconds. They resemble quite closely that reported recently for midlatitude using MU radar. The signal intensities associated with these waves, shown SNR, be as high 25 dB, comparable observed higher altitudes. It is contrast much weaker region echoes by structures show both positive negative rates values 15–20 m s−1, which good agreement Doppler velocities. spectral widths relatively lower, implying less turbulent compared their counterpart bear remarkable resemblance simulated equatorial through nonlocal nonlinear gradient drift instability.