利用武汉电离层观测站1997—2007年电离层TEC资料，采用连续小波变换和交叉小波以及小波相干方法，分析了该站电离层TEC的周期变化特征以及与太阳和地磁活动之间的关系．分析结果表明，武汉站TEC变化的长期趋势主要随太阳活动的强弱而变化；在局部时域上分别存在128-256d，256-512d和512d-1024d的周期尺度，且与同时期的太阳黑子数和地磁Dst指数的周期特征存在很好的对应关系；太阳黑子数在512-024d周期尺度上超前TEC变化约1／6个周期；在准半年的周期尺度上武汉站TEC与地磁Dst指数几乎呈反相位变化，但TEC对Dst指数的这种响应仅在太阳活动高年存在，具体机理尚需进一步分析研究．%By using Total Electron Content （TEC） at Wuhan station from 1997 to 2007, based on continuous wavelet, cross wavelet and wavelet coherence transform methods, the periodic variation of TEC at this station, the characteristic of TEC association with solar activities and geomagnetic activities are analyzed. Analysis results show that long-term variations of TEC at Wuhan station are mainly controlled by the variations of solar activities. In local time field, several remarkable components including 128-256 days, 256-412 days and 512-1024 days time-scale periodicities exist in TEC daily variation and correspond to the periodic characteristics of sunspot number and the rngeomagnetic Dst index closely during the same period of time. The average time delay between variations of the TEC and sunspot number is about 1/6 period in 512-1024 days time-scale. TEC at Wuhan station and geomagnetic Dst index are anti-phasic in semiannual time-scale, but this response only exists during high solar activity, further specific mechanism needed to be analyzed in the future.
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