Latitudinal dependence of the ionospheric response to solar eclipse of 15 January 2010

Abstract

[1] The ionospheric responses to the solar eclipse of 15 January 2010 in the equatorial anomaly region have been investigated by three vertical-incidence and seven oblique-incidence ionosondes arranged along the meridian from geomagnetic latitudes 18°N to 30°N in eastern China. Though the solar eclipse occurred later in the evening, the eclipse effect on electron density and reflection height of ionospheric F2 layer was clearly observed. The study of the eclipse lag (the time lag between the occurrence of the eclipse maximum obscuration and the occurrence of the maximum depletion of foF2) with latitude indicates it increased with F2 layer altitude. Results suggest also that this eclipse enhanced the prereversal enhancement. An unusual peak occurred after the maximum reduction in foF2 and this was observed by all our ionosondes. The following F2 layer plasma density increase was considered to be caused by the increased westward electric field.