Features of Geomagnetic Field Secular Variation at the Midlatitude Mikhnevo and Belsk Observatories

详细

The data from observation of the geomagnetic field variations at the Midlatitude Mikhnevo Geophysical Observatory of Institute of Geosphere Dynamics of the Russian Academy of Sciences, Mikhnevo village, Moscow oblast, Russia (coordinates 54.959° N; 37.766° E) and at the INTERMAGNET international magnetic network station of the Belsk Geophysical Observatory of Geophysical Institute of the Polish Academy of Sciences, Belsk, Poland (coordinates 51.837° N, 20.792° E) in 2008−2016 are analyzed. A long-term trend related to secular variation in the magnetic field of the Earth is studied by the daily-mean values. Annual variation is distinguished in the north horizontal component of the magnetic field. The reliability of the recent version of the International Geomagnetic Reference Field (IGRF-12) model, which was released in December 2014 to describe variations in the main magnetic field at the Mikhnevo and Belsk observatories, is estimated. The 2011 and 2014 jerks are identified.