An integrated and quality-controlled historical datasets of eight pioneering geomagnetic observatories in China

Beijing (IAGA code: BJI), Changchun (IAGA code: CNH), Wuluuqi (IAGA code: WMQ), Lanzhou (IAGA code: LZH), Sheshan (IAGA code: SSH), Wuhan (IAGA code: WHN), Lasa (IAGA code: LSA), Guangzhou (IAGA code: GZH) are the earliest eight pioneering geomagnetic observatories established in China. The layout of these sites is roughly crossover, It constitute the basic framework of China geomagnetic observation network. They undertake the key task of monitoring the spatial and temporal changes of China's magnetic field, accumulated a large number of valuable observation data, laid a foundation for the construction and development of China's geomagnetic network, and made important contributions to the research and development of geomagnetic science in China. The datasets include absolute hourly mean values (AHMV) files of the north component X, east component Y and vertical component Z of the eight geomagnetic observatories, as well as metadata files regarding the description of the datasets. Time range of the AHMV: the year of formal observation- -2022. The datasets can be used to improve the historical geomagnetic field model and carry out the research of the geomagnetic daily variation, the main magnetic field and its long-term changes.