Results 191 to 200 of about 14,504 (230)

Travelling disturbances in the ionosphere

Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1950
Abstract Methods have been developed for the examination of the horizontal and vertical movements of short-period disturbances in the ionosphere. It has been found that quasi-periodic travelling disturbances with periods of from 10 to 60 min. are of frequent occurrence in the F region by day. They appear as temporary variations in the
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Sudden ionospheric disturbances

Terrestrial Magnetism and Atmospheric Electricity, 1937
This paper presents a summary of the data and conclusions up to this time of an investigation, started about the middle of 1935, of a comparatively new phenomenon. The phenomenon is the occurrence of a sudden intense increase in the ionization of a portion of the ionosphere, with resultant transient disturbances in such phenomena as radio‐wave ...
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The dispersion of traveling ionospheric disturbances

Journal of Geophysical Research: Space Physics, 1983
The horizontal dispersion of relatively large daytime TID events seen by the Dartmouth rapid‐run ionosonde network is found to conform, at least qualitatively, to that predicted by previous theoretical treatments of freely propagating gravity waves in the presence of dissipation.
M. G. Morgan, B. L. Tedd
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Observations of Sudden Ionospheric Disturbances

Proceedings of the Physical Society, 1960
Observations were made of the effect of sudden ionospheric disturbances on radio waves reflected from, and transmitted through, the ionosphere. The results of simultaneous measurements of the phase changes on waves of frequency 2-6 Mc/s are shown to indicate that they are due to an increase in the electron density which extends to above the maximum of ...
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Disturbances in the lower auroral ionosphere

Journal of Atmospheric and Terrestrial Physics, 1959
Abstract The solar particles that enter the atmosphere and produce the luminous aurora are known to include protons, which also ionize the atmosphere. As suggested by Bates , their ionizing action may extend below the level of their own penetration, by the Lyman α-photons they emit. These can penetrate to about 75 km, and ionize nitric oxide. Recent
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Lightning spectrometer for ionospheric disturbances

2011 IEEE International Symposium on Antennas and Propagation (APSURSI), 2011
Lightning acts as an electric dipole antenna emitting radio waves that affect the ionosphere. This property is the basis for a new low-cost ground/satellite observation capability to measure dispersion and total electron content in the ionosphere. These properties are important to RF propagation in general and affect the accuracy of GPS.
Rosemary Burns, Zach Chacon, William DeRaad, Anastasia Ierides, Matthew McCullough, Mario Ortega, Steve Suddarth   +6 more
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Ionospheric Interaction in Disturbed Conditions

Proceedings of the Physical Society. Section B, 1951
Measurements of ionospheric interaction depend on special radio transmissions which are only available on a limited number of occasions, and only on some of these occasions are ionospheric conditions steady enough for direct comparison between experiment and theory.
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Detection Methods for Ionospheric Disturbances

2019
Due to the complex spatial distribution and variation of the ionospheric layer, it is difficult to separate or remove each anomaly. The ionosphere has regular variations (daily and seasonal scales) and anomalies due to the magnetic storm, solar flares, and scintillation as well as other hazard events.
Shuanggen Jin, R. Jin, X. Liu
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A study of sudden disturbances of the ionosphere

Eos, Transactions American Geophysical Union, 1937
Research is proceeding on a wide front in the cosmic sciences on a phenomenon which was unknown two years ago. The phenomenon is a sudden and short‐lived increase of ionization of a part of the ionosphere, manifesting itself by perturbations in radio transmission, terrestrial magnetism, and earth‐currents.Whenever the phenomenon occurs, it is most ...
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Epicenter from Ionospheric Disturbances

2019
Epicenter is one of the core parameters in seismology. Accurate and rapid determination of the epicenter has important guidance significance for evaluation and rescue of the earthquake destruction. Meanwhile, the epicenter parameter is also the fundamental for the study of earthquake precursory, evolution process, and long-term material migration.
Shuanggen Jin, R. Jin, X. Liu
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