Wave Disturbances in the Low Latitude Ionosphere and Equatorial Ionosphere Plasma Depletions

摘要

An isolated nightime inospheric wave disturbance was observed by a meridional scanning 6300 a photometer, a 6300 a zenith photometer, a 30 MHz riometer and an ionosonde. Two different scale size for the disturbances are: a larger scale component easily identified in the riometer data similar to those of a large scale TID and smaller scale disturbance observable in the scanning photometer data, occurring during the ascending phases of the larger scale waves. A Fourier analysis of the zenith airglow variations reveals a dominant period of about 104 minutes. No single dominant period is presented for the smaller scale waves. All waves have a poleward velocity component: the smaller scale waves show this feature more markedly. The equatorial source of the smaller scale disturbance suggests that these are perhaps the low altitude manifestations of the upward propagating field aligned plasma bubbles in the equatorial ionosphere.