Ionospheric TEC Variation in Guangxi and Surrounding during High and Low Solar Activity Years
The ionospheric delay error is one of the important error sources that affect the high-preci-sion positioning,navigation,and timing of Global Navigation Satellite System.Using the GIM(Global Ionospheric Map)data provided by CODE from 2000 to 2021 year,the temporal and spatial variation characteristics of ionospheric TEC is analyzed in Guangxi and its surrounding areas at different levels of solar activity in two solar activity cycles,including annual,seasonal,2-hour,and 4-hour time scales.The result show that the numerical magnitude and variation characteristics of ionospheric TEC are influ-enced by the intensity of solar activity.The ionospheric TEC during the high solar activity years is sig-nificantly greater than that during the low solar activity years.The ionospheric TEC exhibits a"bi-modal"pattern throughout the year.The seasonal average ionospheric TEC in spring and autumn is greater than that in summer and winter.The ionospheric TEC exhibits a"winter anomaly"during the high solar activity years,but only appears in parts of regions in certain time periods during the low so-lar activity years.On the spatial frequency domain,with 1° change in longitude from east to west,the variation of ionospheric TEC is mainly concentrated at-2～2 TECU and-1～1 TECU during the high solar activity years and low solar activity years,respectively.With 1° change in latitude from south to north,they are mainly concentrated at-3～1 TECU and-2～1 TECU during the high solar activity year and low solar activity year,respectively.Overall,the variation of ionospheric TEC in the latitude direction is larger than that in the longitude direction.On the time frequency domain,the ionospheric TEC variation increases with the increase of time interval.The 2-hour and 4-hour variations of the iono-spheric TEC showed that a normal distribution,and they are mainly concentrated at-20～20 TECU and-40～40 TECU during the high solar activity years,respectively.But they are all concentrated at-20～20 TECU during the low solar activity years.
IonosphereTotal electron contentTemporal-spatial variationSolar activityGuangxi and surrounding areas
万方数据
维普
