Influence of geomagnetic activity on the parameters of the earth-ionosphere waveguide channel and statistical properties of vlf signals

1978 ◽  
Vol 21 (9) ◽  
pp. 855-858
Author(s):  
V. G. Bezrodnyi ◽  
R. S. Shubova
Keyword(s):  
Geomagnetic Activity ◽  
Statistical Properties ◽  
Waveguide Channel ◽  
The Earth

Statistical properties of Rayleigh waves due to scattering by topography

1967 ◽  
Vol 57 (1) ◽  
pp. 83-90
Author(s):  
J. A. Hudson ◽  
L. Knopoff
Keyword(s):  
Surface Waves ◽  
Rayleigh Waves ◽  
Seismic Noise ◽  
Forward Scattering ◽  
Statistical Properties ◽  
Body Waves ◽  
Simplified Model ◽  
Two Dimensional ◽  
Especial Reference ◽  
The Earth

abstract The two-dimensional problems of the scattering of harmonic body waves and Rayleigh waves by topographic irregularities in the surface of a simplified model of the earth are considered with especial reference to the processes of P-R, SV-R and R-R scattering. The topography is assumed to have certain statistical properties; the scattered surface waves also have describable statistical properties. The results obtained show that the maximum scattered seismic noise is in the range of wavelengths of the order of the lateral dimensions of the topography. The process SV-R is maximized over a broader band of wavelengths than the process P-R and thus the former may be more difficult to remove by selective filtering. An investigation of the process R-R shows that backscattering is much more important than forward scattering and hence topography beyond the array must be taken into account.

On the relation between endogenic activity of the Earth and solar and geomagnetic activity

2009 ◽  
Vol 428 (1) ◽  
pp. 1142-1145 ◽  
Author(s):  
S. V. Belov ◽  
I. P. Shestopalov ◽  
E. P. Kharin
Keyword(s):  
Geomagnetic Activity ◽  
The Earth

Can we perform statistical deconvolution by polynomial factorization?

Geophysics ◽  
1991 ◽  
Vol 56 (9) ◽  
pp. 1423-1431 ◽  
Author(s):  
Anton Ziolkowski ◽  
Evert Slob
Keyword(s):  
Impulse Response ◽  
Seismic Data ◽  
Statistical Properties ◽  
Polynomial Factorization ◽  
The Earth ◽  
True Source ◽  
Free Case ◽  
Multichannel Seismic Data

We investigate the possibility of finding the source signature from multichannel seismic data by factorization of the Z-transforms of the seismic traces. In the convolutional model of the data, the source signature is the same from trace to trace within a shot gather, while the impulse response of the earth varies. In the noise‐free case, the roots of the Z-transform of the wavelet are the same from trace to trace, while the roots of the Z-transform of the impulse response of the earth must move from trace to trace. It follows that the roots of the wavelet can be found by the invariance of their positions. We demonstrate this using a simple wedge model. No assumptions about the length of the wavelet or the statistical properties of the impulse response of the earth are required. It is shown that this idea cannot work on real seismic data. There are two difficulties which we regard as insuperable. First, even without noise, a seismic trace cannot be regarded as a complete convolution, because the data are always truncated. This causes the factorization to be inexact: the wavelet roots move from trace to trace and are indistinguishable from the roots of the earth’s impulse response. Second, the addition of a small amount of noise alters the root pattern unpredictably from trace to trace and the roots of the wavelet are again indistinguishable from the roots of the earth’s impulse response. We conclude that it is impossible to identify and extract the true source signature from real seismic data using no assumptions about the statistical properties of the impulse response of the earth. We propose that the signature should be measured.

scholarly journals Study of Interplanetary and Geomagnetic Response of Filament Associated CMEs

2018 ◽  
Vol 13 (S340) ◽  
pp. 83-84
Author(s):  
Kunjal Dave ◽  
Wageesh Mishra ◽  
Nandita Srivastava ◽  
R. M. Jadhav
Keyword(s):  
Magnetic Field ◽  
Geomagnetic Activity ◽  
Space Weather ◽  
Coronal Mass Ejections ◽  
The Sun ◽  
The Earth ◽  
Weather Events ◽  
Terrestrial Magnetic Field

AbstractIt has been established that Coronal Mass Ejections (CMEs) may have significant impact on terrestrial magnetic field and lead to space weather events. In the present study, we selected several CMEs which are associated with filament eruptions on the Sun. We attempt to identify the presence of filament material within ICME at 1AU. We discuss how different ICMEs associated with filaments lead to moderate or major geomagnetic activity on their arrival at the Earth. Our study also highlights the difficulties in identifying the filament material at 1AU within isolated and in interacting CMEs.

scholarly journals New aspects of the role of development and structure of solar active regions in the arrangements of the corona based on its geomagnetic displays

1968 ◽  
Vol 35 ◽  
pp. 389-389
Author(s):  
B. Bednářová-Nováková ◽  
J. Halenka
Keyword(s):  
Magnetic Fields ◽  
Geomagnetic Activity ◽  
Geomagnetic Storms ◽  
Active Regions ◽  
The Earth ◽  
Local Magnetic Fields ◽  
Normal Shape ◽  
The Individual ◽  
Active Centres

The coronal plasma, which is the cause of geomagnetic storms, can impinge on the Earth only when some coronal formation is pointing towards the Earth. If no such formation is directed towards the Earth, a period of geomagnetic calm follows.It was found that certain coronal formations, governed clearly by the appropriate local magnetic fields, correspond to the individual stages of development of active centres. Above the sunspot groups, there occur either conical rarifications or cylindrical, condensed fluxes dependent on a relatively non-variable, or unstable magnetic field. The filaments which outlive the sunspot period, provided they are located in floccular fields, are appropriate to streamers of helmet shape. The final stage of the active region, characterized by the presence of filaments only (called ‘free filaments’ by the authors), does not change the arrangement of the corona appreciably, i.e. the normal shape, or so-called minimum type. On the basis of the mentioned relations, it is possible to determine the shape and direction of so far currently unobservable coronal structures from chromospheric situations.The mentioned facts enable a unified interpretation of the geomagnetic activity during the whole of the solar cycle to be made. The differences given for some types of storms (sporadic and recurrent, sudden and gradual commencement), may be explained by the various arrangements, occurrences or absences of local magnetic fields. The paper presents examples of chromospheric situations which were used, in some cases, at the Geophysical Institute in Prague for forecasting geomagnetic activity.

scholarly journals Conversion Energy from the Movement of the Solar System through Universal Pressure: Reflections Inseismic Events and Global Temperatures

2014 ◽  
Vol 36 ◽  
pp. 78-86 ◽  
Author(s):  
Michael A. Persinger
Keyword(s):  
Global Warming ◽  
Solar System ◽  
Solar Corona ◽  
Flux Density ◽  
Geomagnetic Activity ◽  
Galactic Center ◽  
Spatial Variations ◽  
Solar Cycles ◽  
Available Energy ◽  
The Earth

The velocity (~242 km·s-1) of the Solar System around the galactic center within the universal pressure (~10-10 Pascal) produces energies within the earth’s volume that is equivalent to that released by the sum of all earthquakes per unit time. The available energy within the earth and solar volume from the expected spatial variations of this pressure along this perimeter, which requires about 250 million years to traverse, can accommodate the increased geomagnetic activity from the expanding solar corona over the last approximately 100 years as well as the increase in global warming. Inferences of a varying structure of space that may explain the periodicity and range in solar cycles as well as anomalous minimums (such as the Maunder phenomenon) suggest a central galactic singularity with spatial ripples exhibiting peak-to-peak troughs that approximate the earth’s circumference and frequencies in the order of 7 to 8 Hz. The precise velocity-universal pressure flux density may also explain the millilux-range magnitude of the earth’s night (air) glow. These results and the application of these concepts indicate that origins of seismicity, slow drifts in the intensity of geomagnetic activity, and global warming (and cooling) trends are products of differential interactions with quantitative fluctuations in sub-matter space and that the subtle variations encountered as the Solar System moves along this 1021 m perimeter may be more significant than previously assumed.

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