Traveling Ionospheric Disturbances Detected During the Solar Eclipse of 24 October 1995

1995年10月24日日蝕期間偵測到的移行電離層擾動

鄭康(Kang Cheng)；黃胤年(Yinn-Nien Huang)；陳盛文(Sen-Wen Chen)

Traveling Ionospheric Disturbances ； Solar Eclipse ； Bow Wave Front Model

Terrestrial, Atmospheric and Oceanic Sciences

8卷2期（1997 / 06 / 01）

213 - 220

英文

The main purpose of this paper is to illustrate the usefulness of ionosondeobservations in the study of the effects due to the transit of a solar eclipse.A sequence of ionograms were obtained during the eclipse on October 24,1995 by the Chung-Li Digisonde(situated at 24.9°N,121.5°E,35.2°N magnetic dip).With fuzzy classification techniques being used,an algorithmwas devised to automatically scale digital ionograms.In correspondingtime,significant depletions of fo E and fo F1 were observed and were indicative of a response to the eclipse effect.Furthermore,a search for the production of atmospheric gravity waves(AGW)induced by the solar eclipsewas investigated using the iso-frequency virtual height profiles with time.Time-frequency spectral analysis using the Wigner-Ville distribution wasapplied to obtain an AGW with a period of 18.5 min in the F1- and thelower part of the F2-1ayers.The induced AGW began at the start of thesolar eclipse and ended a couple of hours after the completion of the eclipse.In contrast,the iso-frequency profiles with time were also spectrally analyzed with the maximum entropy method(MEM).