The geomagnetic field variations and earthquake activity

The presentation focuses on the induced telluric currents in the Earth's lithosphere and their geodynamic impact. The currents in the lithosphere are induced by the geomagnetic variations (magnetic storms with sudden commencement (SSC), polar sub-storms and Sq variations), which originate externally from the ionospheric current system (mainly controlled by solar radiation), as well as by manmade/artificial electromagnetic impact. We analyzed whether external influences under certain conditions might accelerate earthquake occurrences than they normally would have under regular tectonic processes. Specifically, we investigated whether it is possible to find a direct pattern of natural or man-made activity which precedes seismic events and may be useful as a tool of short-term earthquake prediction. In recent years there were a few papers on a possible seismic triggering effect of pulsed electromagnetic signals of technological origin [e.g., 1, 5], where the variations of earthquakes in Tajikistan and Kyrgyzstan as a result of electric current injection into the Earth crust with application of pulsed MHD power system were analyzed. The authors concluded that the number of earthquakes tends to increase 3-5 days after the passage of electric pulse signal. If such an effect occurs, it is possible that a similar effect on the seismicity may be provided by electromagnetic sources of natural origin. First of all, it may be expected from exposure by magnetic storms and the accompanying geomagnetic disturbances. Suggestion about triggering influence of geomagnetic disturbances (SSC) on seismicity in Kyrgyzstan, Kazakhstan and Caucasus (with maximum effect on 2-7 day after the storm commencement) is declared in A recently discovered coupling of daily probability of earthquake occurrence with a local quiet solardiurnal variation of geomagnetic field (Sq-variation) for the most areas of the globe (China, Italy, Greece, California, Austria, etc.) was investigated in detail i

The anomaly of plasmapause and ionospheric trough positions from DEMETER data

International audienceThe paper addresses the study of the specific pattern of the subauroral ionosphere marked with the anomalous positions of the plasmapause, the equatorial boundary of the mid-latitude (main) ionospheric trough, and the light-ion trough under quiet solar and geophysical conditions near the magnetospheric shell with the McIlwain parameter L = 3. The anomaly was identified on the base of data of active experiments with the SURA heating facility on October 2, 2007, which were conducted as part of the SURA-International Space Station (SURA-ISS) program in the framework of the DEMETER satellite mission. Joint analysis of the orbital data from DEMETER and ISS, together with the results of the complex ground-based measurements, shows that the revealed effect, which is characteristic of the premidnight sector north of the Moscow-SURA satellite path, is not local. It is observed in a vast territory, extending from the west to the east along the same L-shell, from at least Sweden to Kamchatka. The conclusions suggested by the DEMETER data are supported by analysis of the meridional distributions of the F2-peak plasma frequencies provided by GPS radio probing of the ionosphere. Comparison of these results with the model latitudinal-longitudinal and meridional distributions of the F2-peak plasma density provided by the IRI 2007 and SMI (Russian standard model of the ionosphere) models shows that the model predictions are at odds with the empirical data

Auroral activity caused by high-power radioemission from the SURA facility

International audienceA series of experimental modifications of the ionosphere in the HF range, performed at the SURA facility base, together with optical measurements onboard the International Space Station (ISS), indicated that such impacts on the ionosphere are effective when the facility operational frequency is higher than the critical plasma frequency (for the main ionospheric F2 layer). The experimental measurements were supported by measurements at ground-based observatories, ISS, and the Demeter and GPS satellites. The analysis results of the entire data set are presented. The ray HF radio tracing for the experiment of October 2, 2007, has been calculated, and it has been indicated that the ionosphere to the north of the facility up to 60°–62° N latitudes was irradiated by the facility beam (the effects of ray redistribution and refocusing) due to refraction on the gradient of the F2 layer critical frequencies. An analysis of the ground-based and satellite measurements (both in the vicinity of a heater and in the magnetically conjugate region) indicates that it is possible to trigger a substorm in experiments with the Sura heating facility

On the possibility of localization of a substorm by using the “Sura” heating facility

International audienceWe present the results of analysis of helio-geophysical conditions for the experiments performed in 2007-2010 to study modification of the ionosphere by high-power radio emission of the “Sura” heating facility. The feature of the experiments is that the operating frequency of the facility exceeded the upper-hybrid frequency for the F2 layer maximum in the ionosphere. All the experiments were performed in the local-time sector of the Harang discontinuity (i.e., from 21:00 to 00:00, local time) to ensure the most probable influence of the facility operation on the onset of natural processes in the subauroral region of the ionosphere. At least two experiments were found to demonstrate that the observed substorm activity in the region of the modification produced by the facility could be stimulated by its operation. The results of the ground- and satellite-based measurements, both in the vicinity of the “Sura” facility and in the magnetically conjugate region, confirm the conclusion about the possibility of substorm localization by this facility

Development of Compact Optical Instrumentation for Studying the Earth Upper Atmosphere Emissions on the Board of International Space Station

Abstract – In presented work the technical pattern of Spectral Photometrical Complex (SPC) is described and the results of calculations of required energetic, spectral and temporal parameters of SPC are given. The plan of experiment “Hydroxyl ” at International Space Station (ISS) with SPC instrumentation supposes carrying out the sessions of observations of Earth upper atmosphere at the night-side of the Earth. The absolute hydroxyl emission intensities will be measured with spectral resolution better then 0.5 nm in region of 830 – 1040 nm together with atomic oxygen green line emission at 577.7 nm. The measurements will be carried out in Earth limb direction. The spatial resolution of emission images is supposed to be better then 1 km