Multi‐Instrument Approach to Study Polarization Jet/SAID and STEVE

Abstract In this study, we employ a unique multi‐instrumental approach for a comprehensive examination of Polarization Jet (PJ) (or, another name, Subauroral Ion Drift (SAID)). A diverse set of data is used to assess the connection between the appearance of the inhomogeneous structure of PJ/SAID and its reflection in ground‐based observations during geomagnetic activity. Our approach combines satellite (Defense Meteorological Satellite Program, NorSat‐1, Swarm) and ground‐based (ionosondes, magnetometers, GPS/GLONASS receivers) data, allowing us to study PJ/SAID in detail and compare satellite data with ground‐based measurements. We describe the characteristic patterns on ionograms that may indicate the presence of PJ/SAID and how ionosondes can be used to study PJ/SAID. Polarization Jet Strata and irregularities of plasma parameters can cause multiple reflections, which are visible in ionograms as F‐spread. The splitting of the F2 trace into two or more traces on ionograms may indicate the presence of PJ/SAID near the observation point. Data from GPS/GLONASS receivers in regions where PJ/SAID is observed enable the construction of local total electron content maps, visualizing how PJ/SAID is reflected in those maps. It is shown how the geomagnetic latitude of PJ/SAID changes during the geomagnetic activity. Furthermore, this case is notable because not only PJ/SAID but also STEVE (Strong Thermal Emission Velocity Enhancement) is observed at subauroral latitudes in Northern Europe during the examined geomagnetic event.