Analysis of helio- and geophysical events in October–November 2021 from comprehensive observations of SHICRA SB RAS

The paper reports the results of comprehensive observations of space weather manifestations during geophysical events at the end of October – beginning of November 2021 at the Yakut meridional geophysical network of SHICRA SB RAS equipped with a complex of various scientific instruments installed at the stations Yakutsk, Maimaga, Zhigansk, and Tixie Bay (neutron monitors, an ionosonde, a riometer, receivers of VLF radio noise and signals from navigation radio stations, magnetometers), as well as a complex of optical instruments installed in Maimaga. We present the results of the analysis of phenomena occurring in near-Earth space, Earth’s ionosphere and atmosphere in the North-Eastern sector of Siberia. We examine the properties of the geophysical effects of space weather observed at this time: Forbush decreases of cosmic rays, geomagnetic storm and substorm, riometric absorption, the occurrence of electrojet, quasi-periodic broadband radio hisses, assess changes in the effective height of the Earth—ionosphere waveguide, F2-layer critical frequencies, absorption of short-wave radio waves, temperature of the neutral atmosphere, radiant auroral band in 557.7 and 630.0 nm emissions, as well as the region of intense auroras and auroral red arc (SAR arc).