根据LF天波的相位和振幅变化监测中层大气扰动

LF无线电波,白天在70-80km的区域被反射,夜间在90-100km的区域被反射.本文根据武昌电离层观象台长期连续的地面LF传播的实验记录,分析研究了上中层大气压力的变化、行星尺度波扰动、冬季异常等上中层大气的特性,并对其中的冬季异常的机理作了简要讨论,从理论上分析了造成冬季异常的原因,除通常所述的因素外,上中层大气中气压下降或温度降低可能也是一个重要因素.并指出地面LF无线电波传播实验是监测和研究上中层大气的某些特性和扰动的一个重要手段,也可以为进一步探索平流层一中层耦合提供某些实验依据.

MIDDLE ATMOSPHERIC DISTURBANCES DETECTED FROM THE PHASE AND AMPLITUDE VARIATIONS OF LF SKY-WAVE

In this paper, the ralationship between the middle atmospheric disturbance and the phase and amplitude variations of the one-hop LF sky-wave is investigated. The long term observation of pulsed 100kHz Loran-C signal, which is transmitted at Iwogima （24°48.1'N, 141°19.5'E） of the master station of SS-3 chain in tht North-Western Pacific and recieved at Wuhan Ionospheric Observatory （30°32.7'N, 114°21.9'E） have been carried out. From the analysis of the long term phase and amplitude variations the annual varition of atmospheric pressure, planetary scale wave disturbances as well as the winter anomaly events of radio wave absorption in the upper mesosphe-re are studied in detail and the results agree generally with ones obtained by other means. In con-clussion, with the analysis method used in this paper, the observation of LF sky-wave is usefull for studying the dynamics of the middle atmosphere.