Ionospheric Data at Syowa Station in 2018

The ionosphere is a region of the earth's atmosphere above an altitude of approximately 60 km, where atoms and molecules in the ionosphere are transformed into electrons and ions due to the effect of solar ultraviolet and x-ray radiation. High-frequency radio waves (at frequencies of 1-16 MHz in Syowa Station) are reflected by this region. International communications and broadcasts that employ HF radio waves are affected by the ionosphere, and it is therefore important that we be able to monitor this the ionosphere."Ionospheric Data at Syowa Station" is an annual data book which contains summary plots and characteristics of ionosphere by using ionospheric observations at Syowa station.电离层（ionosphere）是地球大气层中海拔约60公里以上的区域，受太阳紫外线与X射线辐射的作用，该区域内的原子与分子会被电离为电子和离子。高频无线电波（昭和站观测频段为1-16 MHz）可被该区域反射。使用高频无线电波的国际通信与广播业务均会受到电离层的影响，因此对电离层进行监测具有重要意义。《昭和站电离层数据》（Ionospheric Data at Syowa Station）为年度数据手册，收录了基于昭和站电离层观测数据得到的电离层特征与汇总绘图。