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For the first time, simultaneous observations of very low frequency (VLF) emissions at auroral latitudes ( L = 5.3) are carried out at two points located at close geomagnetic latitudes and spaced in longitude by 400 km: the Finnish Kannuslehto station (Φ = 64.2°) and the Russian Lovozero observatory (Φ = 64.1°). A recording equipment with similar frequency responses was used. The first results of a comparison of simultaneous observations showed that, in the overwhelming majority of cases, bursts of VLF emission appeared at both points synchronously with an identical (more often right-handed) polarization of the magnetic field of VLF waves, which can be evidence in favor of large dimensions of the ionosphere exit region of VLF waves. A simultaneous burst of quasi-periodic VLF emissions that occurred on February 02, 2013, during a substorm at 23-24 UT is discussed in detail. Additionally, VLF bursts were recorded which were observed only at one point, e.g., the appearance of left-hand polarized periodic emissions (PEs) in band 2.5-4.0 kHz with a repetition period of 3-4 s. [ABSTRACT FROM AUTHOR]

Being a rare phenomenon for this region, the thunderstorm was visually observed over the Kamchatka Peninsula in August 2007. The registration of thunderstorm discharges was carried out by the VLF direction finder sited at Paratunka observational point of the Institute of Cosmophysical Researches and Radio Wave Propagation of the Far East Division of the Russian Academy of Sciences. The temporary forms of atmospherics, their frequency characteristics, and azimuthal distribution of thunderstorm discharge number were plotted. The comparison of direction-finding and meteorological parameters demonstrated that the sharp change of wind direction was accompanied by the dramatic increase in the number of thunderstorm discharges. For comparison, the world network data were involved and the latitude-longitude distribution of thunderstorm activity from 45° to 60° N and from 140° to 170° E was plotted. The data comparison revealed their high consistency in detecting the location of thunderstorm discharge sources. [ABSTRACT FROM AUTHOR]

Abstract: We have considered spatial distributions of positive lightning discharges in the east of Siberia for the summer seasons of 2003–2007 and properties of their electromagnetic signals with the ELF “slow tail”, which, as is known, can be accompanied by sprites. There are two main regions of positive discharges located in the south and west of Yakutsk. Two other “centers” (the northeastern and the eastern) are located in high-mountainous regions. In these regions the positive discharges intensity can exceed the negative discharge intensity. The electromagnetic signals in the ELF range (usually in the form of two half-cycles) were observed after the VLF atmospherics were recorded in the high-latitude regions. The delay of ELF pulses relative to the corresponding atmospherics was 0–7ms. The long (up to 350ms) events of quasi-periodic ELF oscillations with the period of about 7ms (which corresponds to the quasi-period of ELF pulses) were revealed. [Copyright &y& Elsevier]

A relation between parameters of preseismic ULF/ELF emissions and EQ is studied. The magnetic data measured at Karymshino station (Kamchatka, Russia) along with data on local seismic activity during eight years of observations (2001-2008) are taken for the analysis. Source azimuth is detected in different techniques, based on the analysis of the total field and its polarized pulsed component. The latter technique shows a better accuracy in the source azimuth detection. The errors of the method are associated with existence of non-seismic sources and with use of one-point observation. The second error can be eliminated by development of multi-point observations. [ABSTRACT FROM AUTHOR]