The system for the preparation of quasi-definitivedata of the INTERMAGNET standard is described. Unlike the final data, which was prepared no earlier than 1 year after the measurement, the data provided with the described system are available 1 day after the last series of absolute observations. Quasi-definitivedata are used to model fast variations in the main magnetic field of the Earth and to calculate indices of geomagnetic activity. The quality of the data obtained from a comparison of the approved final INTERMAGNET data and the data from the World Magnetic Model (WMM) and International Geomagnetic Reference Field (IGRF) model is analyzed. The quality of the quasi-definitive data obtained by the proposed method of automated algorithms is shown to be comparable to the quality provided by the traditional approaches to the preparation of the final INTERMAGNET standard data.

The discrete mathematical analysis (DMA) is a series of algorithms aimed at the solution of basic problems of data analysis: clustering and tracing in multidimensional arrays, morphological analysis of reliefs, search for anomalies and trends in records etc. All the DMA algorithms are of universal nature, joined by the same formal foundation, based, in its turn, on fuzzy logic (FL) and fuzzy mathematics (FM). The current study finalizes the search for the anomalies in one-dimensional time series within the scope of DMA: here the initial concept of an interpreter’s logic gets its additional development. First, the formal expert’s opinions are more fully expressed, and this is realized with the more complex measures of activity (the concept of straightenings (Gvishiani et al. 2003; Gvishiani et al. 2004; Zlotnicki et al. 2005) is replaced by the measures of activity which come to the fore): second, for the junction of anomalies, a recently created DPS (Discrete Perfect Sets) algorithm is used DPS (Discrete Perfect Sets) (Agayan et al. 2011; Agayan et al. 2014)

Since June 2012 the Saint Petersburg magnetic observatory is being developed and maintained by two institutions of the Russian Academy of Sciences (RAS) – the Geophysical Center of RAS (GC RAS) and the Saint Petersburg branch of the Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of RAS (IZMIRAN SPb). On 29 April 2016 the application of the Saint Petersburg observatory (IAGA code SPG) for introduction into the INTERMAGNET network was accepted after approval by the experts of the first definitive dataset over 2015, produced by the GC RAS, and on 9 June 2016 the SPG observatory was officially certified. One of the oldest series of magnetic observations, originating in 1834, was resumed in the 21st century, meeting the highest quality standards and all modern technical requirements. In this paper a brief historical and scientific background of the SPG observatory foundation and development is given, the stages of its renovation and upgrade in the 21st century are described, and information on its current state is provided. The first results of the observatory functioning are discussed and geomagnetic variations registered at the SPG observatory are assessed and compared with geomagnetic data from the INTERMAGNET observatories located in the same region.

In 2011 Geophysical Center RAS (GC RAS) began to deploy the Klimovskaya geomagnetic observatory in the south of Arkhangelsk region on the territory of the Institute of Physiology of Natural Adaptations, Ural Branch, Russian Academy of Sciences (IPNA UB RAS). The construction works followed the complex of preparatory measures taken in order to confirm that the observatory can be constructed on this territory and to select the optimal configuration of observatory structures. The observatory equipping stages are described in detail, the technological and design solutions are described, and the first results of the registered data quality control are presented. It has been concluded that Klimovskaya observatory can be included in INTERMAGNET network. The observatory can be used to monitor and estimate geomagnetic activity, because it is located at high latitudes and provides data in a timely manner to the scientific community via the web-site of the Russian–Ukrainian Geomagnetic Data Center. The role of ground observatories such as Klimovskaya remains critical for long-term observations of secular variation and for complex monitoring of the geomagnetic field in combination with low-orbiting satellite data.