Evolution of the Northern Auroral Oval in Light of Modern Changes in Earth’s Magnetic Field

Abstract

Active development of the Arctic and increased intensity of navigation along the Northern Sea Route and air traffic in the Arctic Ocean airspace draws attention to the problem of disruptions of transpolar radio wave propagation. In high-latitude regions, the passage of navigation signals of global positioning systems depends on the state of the ionosphere. During geomagnetic disturbances, ionospheric inhomogeneities develop that interfere with satellite positioning systems. The position and shape of auroras depend on the state of the magnetosphere. In this study, the component model of the auroral magnetic field has been calculated for the first time using the updated digital model of the full values of Earth’s magnetic field components of the St. Petersburg Branch of the Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation of the Russian Academy of Sciences for the first time. The magnetic field of the auroral zone was calculated for heights from 0 to 1000 km for the period from 1900 to 2023, including for heights of 100–110 km, where the intensity of auroras reaches its maximum in the near-Earth space of the Arctic. The spatial displacement of the auroral oval has been estimated for the period from 1957 (its first mathematical description) to the present. As the analysis showed, the displacement of the boundaries of the auroral oval during the period under consideration has occurred in time and in space codirectionally with the displacement of the isolines of the extremes of the horizontal and vertical components of the auroral magnetic field of the Northern Hemisphere.