Determining dynamic parameters of different-scale ionospheric irregularities over northern Siberia

Abstract In 1995–1996, observations were carried out at Norilsk (geomagnetic latitude and longitude 64.2°N and 160.4°E) to determine dynamic parameters of irregularities in the high-latitude ionosphere. The short-baseline spaced-receiver method that has been implemented at the ionospheric facility of the Norilsk Integrated Magnetic–Ionospheric Station, provides a means of simultaneously measuring parameters of small-scale irregularities (spatial scale of 3–5 km) by the Similar-Fading Method (SFM), as well as of medium-scale irregularities (time scale of 10–30 min, spatial scale of hundreds of kilometres) by the Statistical Angle-of-arrival and Doppler Method (SADM). About 20 h of the observational data for the F2-layer under quiet geomagnetic conditions ( K p K p ≥ 3) and about 15 h for the sporadic E-layer ( K p ≈ 3) were processed. It has been found that the propagation directions and velocities of different-scale irregularities do not coincide. Small-scale irregularities of the F2-layer travel predominantly eastward or westward. The velocity of the F2-layer irregularities is about 100 m/s, and under disturbed conditions it is up to 200–250 m/s. Small-scale irregularities of the sporadic E-layer travel mostly in the northward direction. It is confirmed that the E s -layer is characterised by high velocities of the irregularities (as high as 1000 m/s). Medium-scale irregularities with periods in the range of 10–30 min travel mostly in a southward direction with velocities of 20–40 m/s.