Yu. I. Zetzer

Bio: Yu. I. Zetzer is an academic researcher from Russian Academy of Sciences. The author has contributed to research in topics: Ionosphere & Earth's magnetic field. The author has an hindex of 1, co-authored 4 publications receiving 13 citations.

Influence of meteorological and wave processes on the lower ionosphere during solar minimum conditions according to the data on midlatitude VLF-LF propagation

Abstract: The statistical characteristics of the intensity of VLF-LF radio signals transmitted from the midlatitude radio stations and recorded by the receiver at the Mikhnevo geophysical observatory (54.94°N, 37.73°E; Institute of Geosphere Dynamics, Russian Academy of Sciences) in 2007–2010 are analyzed. The experiments revealed strong variations in the intensity of radio signals during the deep solar minimum conditions, when the medium does not experience impacts from above associated with solar and geomagnetic activity. We relate the observed variations to the disturbances from below, which are caused by the meteorological and wave processes occurring in the lower atmosphere.

Variations of the electromagnetic fields and ionospheric parameters in the Baikal Rift Zone

Abstract: Variations in the geomagnetic and electric fields and variations of the total electron content (TEC) of the ionosphere recorded in the Baikal Rift Zone (BRZ) during the expeditions in 2009 and 2010 are analyzed Synchronous bursts in the geomagnetic field on the ground and in the ionosphere, which are caused by propagation of electromagnetic disturbances (spherics) generated by the remote lightning discharges, are revealed The analysis of the occurrence frequency of the electromagnetic disturbances at an altitude of ∼700 km shows that there is a preferred region of predominant propagation of these disturbances from the Earth-ionosphere waveguide to the upper ionosphere When the ionospheric penetration point moves through this preferred region, the frequency spectrum of TEC variations changes, and the northern boundary of the region of spectral alteration is located at ∼54°N The bursts in TEC that map on the zones of the main faults in the Tunka valley are identified The results probably suggest a relation between the electromagnetic phenomena in the ionosphere and the structures in the lithosphere

Investigation of The Atmosphere and Ionosphere by The Radiophysical Measuring Complex of The “Mikhnevo” Geophysical Observatory

Abstract: A study of appearance and spatio-temporal dynamics of disturbances of the atmosphere, the upper and lower ionosphere, require of integrated investigations of interrelated processes at different altitudes and in different geophysical conditions. In the observatory of IDG RAS "Mikhnevo" created the unique radiophysical complex, allowing to carry out of coordinated measurements of variations of the geomagnetic field, propagation of SW, LW and VLF radio signals, variations of electric fields and atmospheric currents. Analysis of the data of measurements of the total electron content of the ionosphere with phase and amplitude of the signals of LF-VLF range on global and regional routes allows to obtain data on the features of the structure and dynamics of the ionospheric plasma in the mid-latitude zone of the European part of the Russian Federation. The coordinated analysis of GNSS and VLF signals makes it possible to study the mechanisms of the relationship between the perturbations of the upper and lower ionosphere and the dynamics of the ionosphere in the horizontal and vertical directions.

Key Principles of Constructing Probabilistic Statistical Ionosphere Models for the Radiowave Propagation Problems

Abstract: It is demonstrated that it is required to create probabilistic statistical models of the ionosphere for calculating radio propagation in a wide frequency range. This, in fact, presents a new type of ionospheric modeling. These models are classified into pure statistical and deterministic-stochastic. We describe the key principles of building such models, present some examples of their construction, and discuss some difficulties arising from them.

Modeling of the lower ionosphere climate

Abstract: A coupled model of the troposphere-stratosphere-mesosphere and the ionospheric D region (for 0–90 km altitudes) is presented. The model is based on a three-dimensional general atmospheric circulation model in a hybrid coordinate system. A five-component model has been taken as a photochemical model for the lower ionosphere. The role of the neutral atmosphere thermodynamic characteristics in the formation of the D layer mean state has been investigated by the model results. Based on a preliminary model identification using direct measurements, and radiowave absorption and propagation, it has been indicated that the model satisfactorily reproduces climatic characteristics of the ionospheric D layer.

3D-FEM simulation model of the Earth-ionosphere cavity

Abstract: ABSTRACT Radio waves of extremely low frequencies (5–40 Hz) propagate in a special way. Since their wavelengths correspond to the Earth's radius, global resonances are found inside the cavity bounded by the Earth’s surface and the lower ionosphere. These so-called Schumann resonances form a system of standing waves around the planet. They can be a powerful tool for investigating the electrical processes occurring in the lower ionosphere. This paper describes finite element method (FEM) simulations in the frequency domain of Schumann eigenmodes in 3D inhomogeneous Earth-ionosphere cavity. Such an approach provides result independence from source configuration and allows to separate ionosphere configuration influence on Schumann resonances. Also the approach visually reproduces line splitting in the global resonances. The ionosphere was modeled by a simple conventional vertical conductivity profile and by means of a complex 22-species plasmachemical model. Obtained simulation results are compared with the experiment and discussed.

Impact of sudden stratospheric warmings on equatorial ionization anomaly

Abstract: [1] We investigate the ionospheric response to several stratospheric sudden warming events which occurred in Northern Hemisphere winters of 2008 and 2009 during solar minimum conditions. We use GPS total electron content data in a broad latitudinal region at ±40° geographic latitude and a single longitude, 75°W. In all cases, we find a strong daytime ionospheric response to stratospheric sudden warmings. This response is characterized by a semidiurnal character, large amplitude, and persistence of perturbations for up to 3 weeks after the peak in high-latitude stratospheric temperatures. The ionospheric perturbations at the lower latitudes usually begin a few days after the peak in stratospheric temperature and are observed as an enhancement of the equatorial ionization anomaly (EIA) in the morning sector and a suppression of the EIA in the afternoon sector. There is also evidence of a secondary enhancement in the postsunset hours. Once observed in the low latitudes, the phase of semidiurnal perturbations progressively shifts to later local times in subsequent days. This progressive shift occurs at a different rate for different stratospheric warming events. The large magnitude and persistence of ionospheric perturbations, together with the predictability of stratospheric sudden warmings several days in advance, present an opportunity to investigate these phenomena in a systematic manner which may eventually lead to a multiday forecast of low-latitude ionosphere conditions.