第七届青年地学论坛

A moon shadow of annular solar eclipse passed through East Asia in the afternoon on 21 June 2020, which was a good opportunity to study the rapid ionospheric response to the solar radiation variations. In the study, the high-frequency echoes recorded by the ionosondes at Wuhan (82.4% obscuration), Xiamen (97.8% obscuration), and Nanning (81.1% obscuration) are analyzed to examine the variations in sporadic-E (E_s) during the obscuration over the East China area. The echoes show not only the variations in the typical signal E_s layer below 130 km, but for the first time also the multilayered E_s at much higher altitudes (130–190 km) during the eclipse. Specifically, the multilayered E_s is only observed over Nanning, while different E_s behaviors are observed in the other two stations. The relationship between the formation of the multilayered E_s and the uplifted E_s near the center path of the moon shadow are examined in the study. The small-scale atmospheric gravity waves play a key role in modulating the E_s behaviors during the eclipse.
 

sporadic-E,;solar eclipse,;gravity waves