During geomagnetic storms, ionospheric storms can be driven by several mechanisms. Observations performed using ground- and space-based instruments were used to reveal the driver of positive storm over South American sector during 4 November 2021 storm. The appeared from 10:30 UT 18:00 covered region 40°S 20°N. maximum magnitudes TEC (Total Electron Content) enhancement relative about 20 TECU 1...

In the present work we use the NASA-JPL global ionospheric maps of total electron content (TEC), firstly to construct TEC maps (TEC vs. magnetic local time MLT, and magnetic latitude MLAT) in the interval from 1999 to 2005. These TEC maps were, in turn, used to estimate the annualto-mean amplitude ratio, A1, and the semiannual-to-mean amplitude ratio, A2, as well as the latitudinal symmetrical ...

This study compares the Isis II satellite measurements of the electron density and temperature, the integral airglow intensity and volume emission rate at 630 nm in the SAR arc region, observed at dusk on 4 August, 1972, in the Southern Hemisphere, during the main phase of the geomagnetic storm. The model results were obtained using the time dependent one-dimensional mathematical model of the E...

Abstract A near-real-time computerized ionospheric tomography (CIT) technique was developed over the East Asian sector to specify 3-D electron density field. The is based on a plethora of Global Navigation Satellite System observables within region interest which bounded horizontally 110°–160°E and 10°–60°N extending from 80 25,000 km in altitude. Prior deployment, studies validated CIT results...

Earlier revealed morphological features of the foF2 and hmF2 long-term trends are interpreted in the scope of the geomagnetic control concept based on the contemporary F2-layer storm mechanisms. The F2-layer parameter trends strongly depend on the long-term varying geomagnetic activity whose effects cannot be removed from the trends using conventional indices of geomagnetic activity. Therefore,...

A 30-day incoherent scatter radar (ISR) experiment was conducted at Millstone Hill (288.5 E, 42.6 N) from 4 October to 4 November 2002. The altitude profiles of electron density Ne, ion and electron temperature (Ti and Te), and line-of-sight velocity during this experiment were processed to deduce the topside plasma scale height Hp, vertical scale height VSH, Chapman scale height Hm, ion veloci...

A Neural network (NN) is a promising tool for the tomographic inversion of ionosphere. However, existing research has adopted an unbalanced cost function training purposes and preset image constraint purposes, resulting in output being dominated by measurements. To address these problems, we proposed NN-based model with balance dynamic correction process (BCDC) ionosphere inversion. The compose...

In this study, we investigate the global ionospheric impact of high-speed solar wind streams/corotating interaction regions (HSS/CIR). A series ten such events are identified between December 1st 2007 and April 29th 2008, characterized in frequency domain by main spectral peaks corresponding to 27, 13.5, 9 6.75 days. The spectra magnetic field, speed proton density, as well those geomagnetic in...