Elena Romanova

Modeling z-shaped disturbance along the Pedersen ray of oblique sounding ionogram using adaptation of IRI to experimental data

We present the results of numerical modeling of a traveling ionospheric disturbance that causes z-shaped bends at the Pedersen ray of oblique incidence ionograms. The results of trajectory synthesis of oblique incidence ionograms are given for the ionosphere, taking into account the traveling ionospheric disturbance. In the work, we use the International Reference Ionosphere, adapted to experimental data, and the Global Model of the Ionosphere and Plasmasphere.

Backscattering dynamics during intense geomagnetic storm as deduced from Yekaterinburg radar data: March 17–22, 2015

This paper examines the spatio-temporal dynamics of backscattering signals during St. Patrick’s Day two-step intense geomagnetic storm from the Yekaterinburg Coherent Radar (YeKB radar) data. It is found that a number of ground backscattering signals increased during the initial phase of the storm and decreased during the second step of its main phase and the first two days of its recovery phase. Changes in ionospheric backscattering signals started at the beginning of the main phase. During the first step, there was a six-hour sequence of ionospheric backscattering signals (BSi signals) the range of which decreased while the storm was in progress. During the last 5 hours of the main phase and the first 3 hours of the recovery phase, the YeKB radar observed only signals scattering in the E region of the ionosphere. We conduct a complex analysis of data from the YeKB radar, ground-based ionospheric, riometric, and magnetic stations located within the radar field of view. The analysis shows that the observed backscattering dynamics was caused by the magnetosphere compression, expansion of convection cells, impact ionization, and changes in atmospheric composition during the initial storm phase, first and second steps of the main phase, and the recovery phase respectively.

Spatial distribution of total electron content in the Arctic region of Russia from GPS data

Аннотация. Представлены предварительные результаты исследования пространственного распределения полного электронного содержания (ПЭС) в Арктическом регионе России. Исследование выполнено по данным двухчастотных фазовых измерений, полученным в период 04:00–10:00 UT 4–6 мая 2013 г. на четырех высокоширотных станциях GPS: LOVJ (Мурманск), NRIL (Норильск), TIXI (Тикси), BILB (Билибино). На некоторых лучах приемник — спутник GPS, проходящих к северу от станций, обнаружены резкие падения или возрастания ПЭС, которые свидетельствуют о существовании в ионосфере области с пониженной электронной концентрацией (провал ионизации). На основе анализа перемещения лучей приемник — спутник GPS установлено, что ионосферный провал лежал в области широт 72– 84° N и долгот 0–200° E. Полученные результаты согласуются с данными численного моделирования.