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Author's Kit |
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Preliminary Results of Investigations of Variations of Atmospheric Electric Parameter Peculiarities Over Tectonic Fractures and During Earthquakes |
A.G.Amiranashvili,
V.A.Chikhladze, R.A.Gambashidze, A.T.Khunjua,
A.G.Nodia |
Some results of the analysis of the atmosphere electric field strength variability and air electric conduction in Dusheti (in 45 km from Tbilisi) during some earthquakes, have been presented. In particular, in a number of cases, sharp growth of air electric conduction is observed a day before earthquake, apparently connected with increase of radon emanation. The cases of air electric field strength and air electric conduction a day before strong earthquakes with epicenters in Dmanisi, January 2, 1978, (95 km from Dusheti) and in Spitak, December 7, 1988 (145 km from Dusheti) have been presented. Since 2001, electric field strength, light ion content, radon concentration were measured over tectonic fractures in different regions of Georgia in a dry, calm weather. Discreteness of measurements made 20-50 m in distance and 10 min in time, duration - two hours. Over tectonic fractures, increased radon content, high level of electric field strength variability and light ion concentrations were observed. E.g. while measuring in the zone of tectonic fracture of Shio Mgvime region (40 km from Tbilisi), November 21, 2001, radon content exceeded a background value outside the fracture almost 3 times. Concentration of light ions varied from 400 to 1200 cm^-3 (background value outside the fracture was 250 cm^-3) Electric field strength varied from 120 to 250 v/m (background value outside the fracture made 110v/m). Possibility of the use of atmosphere electricity parameters as forerunners of earthquakes, assessment of tectonic activity of fractures and specification of their limits are under consideration, at present. |
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Aeroelectrical constituant in the database of Borok Geophysical Observatory |
Anisimov S.V., Dmitriev
E.M. |
The informatization of geomagnetic and aeroelectrical researches stimulated application of digital technologies directly to datalogging systems, creation of geophysical databases, with access via Internet. In the report the presentation of air electrical parameters in measuring complex and database of the mid latitude Geophysical observatory "Borok", as an example of effective application of information technologies in monitoring of air electric field and current, is considered. Now Geophysical observatory "Borok" remains unique mid latitude geophysical observatory in Russia, leading continuous observations of geomagnetic and air electric fields, air electric current and telluric currents, atmospheric pressure pulsations, Doppler sounding of an ionosphere and some meteorological parameters [1-3]. The measuring complex of an Observatory includes sensors, amplifiers, analog filters, system of a power supply and synchronization. The atmospheric electrical parameters are observable in frequency band 0-5Hz. The datalogging network (see Figure) works continuously, providing the data to database in real time. The analog signals from sensors and synchronization signals from high-precision quartz clock AKV-2M come in a main datalogging system, with the built-in analog-to-digital converter. Then the raw numeric data are transmitted to data processing computer to format, average, transfer in physical values, create the graphic files with data plots, transfer data and graphic files to the database server. The database server carries out a database storage and Internet access to data via the database web-site (http://geobrk.adm.yar.ru:1352). Now, the database includes the data on atmosphere electric current density, measured by the current collector, and electric field strength, measured by the electrostatic fluxmeter. The data are presented in physical values. Sample rate is 10Hz. The access via Internet is free to the data on electric field strength (http://geobrk.adm.yar.ru:1352/electric), averaged over 1 hour, from May 1997 up to present time. Figure. The local datalogging network. References: 1. S.V.Anisimov, S.S.Bakastov, E.M.Dmitriev, E.B.Anisimova, Aeroelectrical
measurements in geoelectromagnetic complete set of Geophysical observatory
"Borok", in Proceedings 11th International Conference on Atmospheric Electricity,
Guntersville, USA, 630-633, 1999. |
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Structures and Spectra of Turbulent Pulsations of Electric Field in the Atmosphere |
S. V. Anisimov , N. M. Shikhova, E. A. Mareev |
Short-term ( |
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Wide variations of atmospheric electric field potential gradient near the ground and meteorotropic reactions in cardiac patients |
E.P.Borisenkov V.A.Filippov, E.N.Kobzareva, I.A.Krushatina,
L.N.Nikiforova Ya.M.Shvarts V.G.Uspenskaya |
Most scientists consider that the meteorotropic reactions are caused by wide variations of the atmospheric pressure. This variations occur as atmospheric processes change during frontal passages. In these conditions other atmospheric characteristics can change too. Attention was drawn to the atmospheric electric field behaviour. The relation is considered between variabilities of the atmospheric electric field potential gradient V', the atmospheric pressure P and the condition of cardiac patients. The observations were conducted close to Saint -Petersburg at different times of the years 1997- 2002. The patients were under treatments at sanatorium. The daily amount M of their requests for a medical care were noted. The main results are following. It was found that the wide changes of P were followed by the wide changes of V' down to going from positive values to negative values of V'. It turned out that the amount M increased considerably over above mentioned periods of the wide variations of P and V'. These periods fell on the winter and transitional seasons mainly. The increase of M was ascribed to meteorotropic reactions in cardiac patients. Usually the negative V' correlated to the precipitation. To reveal the factors which could be the causes of meteorotropic reactions, attention was given to the observations in the summer-time. It is in summer months that the considerable variations of V' occur on the background of the less pronounced changes of the atmospheric pressure. It turned out that a good correlation was between the wide changes of V' and the meteorotropic reactions in cardiac patients. The reactions appeared in the less pronounced changes of the atmospheric pressure. It was found that the change of V' preceded the drop of P in the event that prefrontal systems of clouds and precipitation were in existence. A formation of large anomalies of V' is primarily due to a formation of cloudiness and rain fields. As for the atmospheric pressure, its changes therewith relate to attendant other than governing factors which are responsible for the meteorotropic reactions in cardiac patients. |
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Seismo- atmospheric disturbance observed by anomalous transmission of VHF electromagnetic waves |
M. Kamogawa M. Kamogawa,
H. Fujiwara H. Ofuruton J.Y. Liu, Y.J. Chuo H. Tanaka |
Study of Seismo-Electromagnetics has been developed
recently [1]. Also, the ionospheric disturbance associated with earthquakes has
been reported [2-4]. In this paper, we tried to confirm the atmospheric or
ionospheric disturbance over the epicenter before the earthquake, observing
anomalous transmission of VHF electromagnetic waves. VHF electromagnetic wave
scattered by atmospheric or ionospheric disturbance in the over-the-horizon
propagation could be observed during approximately one year in Japan. We used
the median of the amplitude of the received VHF electromagnetic wave during
midnight as one-day data. When we compare the variation of the one-day data
with the upper bound derived by the previous 10 days running median of the
one-day data and the associated 2 times inter-quartile range, some signals
exceeding upper bound might appear a few days before M References: [1] S. Uyeda and S. Park (Eds.), Recent Investigations of electromagnetic variations related to earthquakes, J. Geodynamics, 33 (2002) [2] O.A. Molchanov and M. Hayakawa, Subionospheric VLF signal perturbations possibly related to earthquakes, J. Geophys. Res., 103, 17489-17504 (1998) [3] J.Y. Liu, Y. I. Chen, S. A. Pulinets, Y. B Tsai, and Y. J. Chuo, Seismo-ionospheric signatures prior to M³ 6.0 Taiwan earthquakes, Geophys. Res. Lett., 27, 3113-3116 (2000) [4] J.Y. Liu, Y.I. Chen, Y.J. Chuo, and H.F. Tsai, Variations of ionospheric total electron content during the Chi-Chi earthquake, Geophys. Res. Lett., 28, 1383-1386 (2001) |
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Electrode Effect under Alpine Conditions |
Electrode effect theory consists of two extreme cases: classical (nonturbulent) electrode effect and turbulent electrode effect. In the first case electrical state of the surface layer is determined by electric field. In the second case turbulent diffusion takes place simultaneously with the electric field, at that turbulent diffusion may be of the main role. Experimental measurements, carried out under Alpine conditions near Elbrus, included potential gradient, air polar conductivity, electric current density, condensation nuclei number (less than 5.108 m-3 ) and ionization rate (about 20 ion pairs/m3 sec) . Electric field is characterized by great values of the potential gradient (about 500v/m), caused by orography. As a result classical electrode effect equations may be used for interpretation of data, in particular for electric field global variations studying against a background of local changes, caused by meteorology. |
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Atmospheric Electrical Thermal Detection for Sailplanes |
Ralph Markson |
This report will summarize ongoing research to develop methods for remote detection of thermals using atmospheric electrical instrumentation on sailplanes. The method as initially conceived was to measure the horizontal field set up by positive fair-weather space charge accumulated in thermals. It turned out that the negative space charge, which accumulates near the base of cumulus clouds, provides a signal that appears to be stronger and more easy to use than the field set up by positive fair-weather space charge. The work began 30 years ago utilized radioactive probes on the front and rear of a glider. It soon became evident that the vertical fair-weather electric field (order of 100 V/m), picked up through the inevitable pitching of the glider, swamped the small horizontal electric field (order of 1 V/m). The advent of new relatively inexpensive solid-state gyros makes it possible to measure the pitch and roll angles and automatically compensate for the unwanted component from the vertical field. Experiments are being conducted with a sailplane instrumented to measure the front-to-rear and wingtip-to-wingtip electric field components using radioactive probe/electrometer circuitry. The vertical field also is measured so its magnitude times the sine of the pitch and bank angles can be used for vertical field compensation. In addition, conductivity is measured with a Gerdien tube on the nose of the glider in an attempt to measure the ionizing radiation from radon emitted at the ground that is carried aloft in thermals. The air from thermals reaches the inversion and spreads out horizontally so increases in conductivity indicate the proximity of thermals. The testing with 2-axis gyro compensation has begun recently and there is not much data yet, but results are encouraging. The glider now can be pitched and rolled modestly with no pickup of the vertical field. From past experience, it appears that some thermals can be detected at distances of at least 2 miles. Another potential application of the technology is providing the pilot with information on which direction to turn when entering a thermal. In previous atmospheric electrical research the horizontal electric field has hardly ever been studied as the vertical field was the parameter of interest and the horizontal field was considered "noise". However, this parameter may make possible remote detection of regions of lift and thus could provide a breakthrough in the science and technology of soaring. This information will be particularly useful on days when there are no clouds to mark likely locations of thermals. The presentation will discuss progress in this research during the period fall 2002 through spring 2003. |
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The Latest Aspects of Seismo-electromagnetic Observations in Japan |
T. Nagao, K. Sayanagi, S. Uyeda K. Hattori M. Kamogawa
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RIKEN International Frontier Research Group on Earthquakes promoted Seismo-Electromagnetics from 1997 to 2002 as a national project in Japan. Major observations in the research program were DC geoelectric potential changes and ultra low frequency geomagnetic changes. In the measurement of the geoelectric potential changes, the so-called SES, extensively studied by the VAN group in Greece [1], we tried to reproduce the Greece results in Japan and finally obtained hopeful results [2]. Furthermore, in the summer of 2000, we had intense earthquake swarms and volcanic activities in and around Izu Islands, Japan. Significant anomalous changes in the ultra low frequency range (~0.01Hz) were observed in both geoelectric and geomagnetic fields before the major activity [3]. The spectral intensity of the geoelectric potential difference between some electrodes on Niijima Island and the third principal component of geomagnetic field variations at an array network in Izu Peninsula started to increase from a few months before the onset of the volcano-seismic activity. culminating immediately before near by magnitude 6 class earthquakes. Appearance of similar changes in two different measurement conducted at two far apart sites seems to provide information supporting the reality of preseismic electromagnetic signals. Moreover, our research group is trying the detail observation and clarification of generation mechanism of Lithosphere-Atmosphere-Ionosphere coupling associated with earthquakes. References: [1] J. Lighthill (Ed.), A Critical Review of VAN (World Scientific, Singapore) (1996) [2] S. Uyeda, T. Nagao, Y. Orihara, T. Yamaguchi, AND I. Takahashi, Geoelectric Potential Changes : Possible Precursors to Earthquakes, Proc. Nat. Acad. Sci., USA (PNAS), 97, 4561-4566 (2000) [3] S. Uyeda, M. Hayakawa, T. Nagao, O. Molchanov, K. Hattori, Y. Orihara, K. Gotoh, Y. Akinaga, and H. Tanaka, Electric and magnetic phenomena observed before the volcano-seismic activty in 2000 in the Izu Island Region, Japan, 99, 7352-7355 (2002) |
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Statistic structure of variations of vertical "atmosphere-earth" currents |
A.I. Petrov, G.G.
Petrova, I.N. Panchishkina |
Salient features of atmosphere-earth charges exchange are to a great extent connected with the difference in physical conditions of observation points. The investigations show that the statistic structure of variations of vertical atmosphere-earth current components differs for the observation point with sufficiently distinguishing physical-geographic conditions. Under that a judicious interpretation of observed differences together with he attraction of meteorological parameters of the lower 2 m. layer is feasible, what once more demonstrates an integral relation of electrical and meteorological characteristics of the atmosphere. In the investigation the results of the experimental studies, carried out during the last years in summer months in Rostov region and on the Baikal shore are presented. (The description of the measuring setup and the points of observation is given in the earlier published investigations). Empirical variational series are plotted for the vertical atmosphere-earth current components and theoretical curves are calculated corresponding the normal distribution of each parameter. Experimental curves being plotted for the points of observation in Rostov region in the measurements of density mechanical transfer current show the left-hand (negative) asymmetry and positive excess in comparison with the normal curve. Empirical variational series and theoretical curves corresponding the normal distribution of the values of the conductivity atmosphere-earth current density have also sufficient differences. Comparing these curves, one can note the right-hand (positive) asymmetry and the positive excess in comparison with the normal one. At the same time, empirical distributions of conductivity current density and the density of mechanical "atmosphere-earth" transfer current being plotted according to the Baikal expedition 1991 are close to normal. Further an attempt is done in the investigation to interpret the appearance of asymmetry and the excess in vertical atmosphere-earth electrical current component distribution, proceeding from the microclimatic particularities of the points of observation. |
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Diurnal and seasonal variations of
radioactivity and electrical conductivity near the surface for a continental
location Mysore |
Prasad B S N, K Nagaraja, M
S Chandrashekara, L
Paramesh and M S Madhava |
Near the earth surface, radioactive gases are released from the soil because of the presence of radioactive minerals. These gases ionize the molecules, and Aitkin particles, small sized aerosols. The ionization gives rise to electrical effects, one of which being the conductivity, in the atmosphere. In the present work the diurnal and seasonal variations of radioactivity and electrical conductivity are reported for a continental location Mysore. The electrical conductivity is an important parameter in the field of atmospheric electricity. Radioactivity due to radon and its progeny are measured respectively with Low Level Radon Detection System (LLRDS) and Air flow meter by the application of established procedures. And the ion production rate (q) is determined. A locally fabricated Gerdien condenser with two identical tubes and a common fan to suck the air through them is used to measure the electrical conductivity of both positive and negative ions. The figure is a typical diurnal representation of the variation in ion pair production rate and conductivity. During fair weather conditions the atmospheric stability varies from very unstable during daytime to most stable during nighttime. The diurnal variation exhibits a maximum in the early hours and gradually decreases reaching a minimum in the afternoon or early evening. This may be due to; during the nocturnal temperature inversions the radioactive gases can be trapped in a concentrated layer close to the ground, whereas during unstable convective period, the gases can be dispersed over an altitude of several kilometers. Combining the diurnal results a seasonal variation is established. It is observed that the winter exhibit maximum, in general. This may be attribute to the low turbulence and stable conditions because of low temperatures in the winter. |
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Neural networks and wavelet analysis of the atmospheric 7Be radioactivity changes and its relation to ground level air conductivity |
Z. Moroz, B. Myslek-Laurikainen, M.Matul, S. Mikolajewski, H.Trzaskowska, Z.
Preibisz, C. Kownacki M. Kubicki |
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Cosmogenic 7Be, the most abundant naturally formed radioactive element in the atmosphere is the object of air radioactivity monitoring carried out by numerous air-sampling stations in the world. The seasonal concentration changes related to air conductivity variations are object of research presented in this work. In particular the elaboration of prediction methods has essential meaning for the assessment of environmental pollution proliferation. Computational methods of artificial intelligence and modern signal processing were applied for the analysis of the atmospheric radioactivity data. As a test data the results of 7Be measurements performed weekly during 1994-2001, were used. Artificial neural networks were tested as tools for approximation, interpolation and for prediction of the data. The time sequences of the experimental data were decomposed using the wavelet method and eight wavelet components of different time scales were obtained. Neural networks were applied separately to each of those components. Ability of neural prediction of different wavelet components is demonstrated. Applications of such analyses and possible extensions as complementary method useful for the construction of phenomenological models of atmospheric pollution changes are discussed. |
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Last Update : May 6, 2003 |