本研究分析2020年6月21日的低緯度日環食、2021年6月10日的北極日食和2021年12月4日的南極日食三個日食事件之電離層響應。三顆衛星，FORMOSAT-7/COSMIC-2（F7/C2）、Ionospheric Connection Explorer（ICON）和Swarm衛星被用來觀察2020年6月21日的日環食事件。然而，只有Swarm可用來觀察2021年6月10日的北極日食和2021年12月4日的南極日食事件。F7/C2和ICON配備了離子速度儀(Ion velocity meter)，量測離子溫度、密度和上移速度。Swarm則使用其電場儀器(Electric Field Instrument)來記錄電子溫度和密度。結果顯示，食甚後，離子和電子溫度下降了約100-1100 K。在月球的陰影下，離子和電子密度明顯減少30%至50%，而在初窺前則有增加約50%。此外，食甚附近，離子垂直地表向上速度呈減少之趨勢，然而卻在初虧附近則增加。值得注意的是，這些變化在緯度位置上具有明顯差異，例如：高緯度地區的電子溫度減少更為明顯，而低緯度地區的電子密度減少則更為明顯。日食當天之月相為新月，由於其潮汐力效應，導致赤道異常區(Equatorial Ionization Anomaly)密度顯著地增加。;Responses of ionospheric plasma to three solar eclipse events, the 21 June 2020 annular solar eclipse in low latitudes, the 10 June 2021 solar eclipse over the north pole, and the 04 December 2021 solar eclipse over the south pole, are studied. In-situ measurements of the ion/electron temperature, density, and ion upward velocity probed by the ion velocity meter (IVM) onboard FORMOSAT-7/COSMIC-2 (F7/C2) and Ionospheric Connection Explorer (ICON), and the electric field instrument (EFI) onboard Swarm satellites are used to observe ionospheric solar eclipse effects at various latitudes. The ion and electron temperatures decrease by about 100-1100 K during the maximum obscuration. The ion/electron density experience significant decreases of about -30－-50% under the Moon′s shadow, and however, yield enhancements around +50% around the first contact. It can be found that the ion upward velocity decreases around the maximum obscuration while increasing at the first contact. Notably, these variations exhibit differences across latitudinal locations, such as more pronounced electron temperature decreases in higher latitudes, and however, obvious electron density reduces more in the lower latitudes. Since solar eclipses occur on the new Moon day, the lunar tide results in the equatorial ionization anomaly symmetrically enhance.
