Results 241 to 250 of about 546,299 (291)
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Canadian Journal of Physics, 1969
Backscatter probings (at 28 MHz) of the arctic ionosphere were made at Alert, Canada, for almost two years. A skewed distribution around the site was found with (a) maximum occurrences constrained to the northeast within ±30° of the great circle through Alert and the principal northern magnetic dip pole, (b) a secondary maximum to the south, and (c) a
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Backscatter probings (at 28 MHz) of the arctic ionosphere were made at Alert, Canada, for almost two years. A skewed distribution around the site was found with (a) maximum occurrences constrained to the northeast within ±30° of the great circle through Alert and the principal northern magnetic dip pole, (b) a secondary maximum to the south, and (c) a
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Journal of Atmospheric and Solar-Terrestrial Physics, 2005
Abstract This is a study of the sporadic E (Es) that is observed over a ‘cusp latitude’ station, Cambridge Bay (77° CGM lat.). Es is extremely common in late evening hours at this location, reaching ∼80% occurrence rate in some months. The Es appears to form near the time when the convection reversal passes over the station.
John W. MacDougall, P.T. Jayachandran
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Abstract This is a study of the sporadic E (Es) that is observed over a ‘cusp latitude’ station, Cambridge Bay (77° CGM lat.). Es is extremely common in late evening hours at this location, reaching ∼80% occurrence rate in some months. The Es appears to form near the time when the convection reversal passes over the station.
John W. MacDougall, P.T. Jayachandran
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Theory of equatorial sporadic-E
Journal of Atmospheric and Terrestrial Physics, 1963Abstract It is shown that when sound waves travel at right angles to the magnetic field in the lower E -region near the earth's magnetic equator, marked build up of electron density irregularities is possible. The theory indicates that whilst the electron density irregularities may be much more intense than the corresponding air density variations ...
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Geofisica pura e applicata, 1950
Abstract Sporadic E trajectories determined over the United States seem to indicate atmospheric movements at 110 kilometers which are predominantly from the east during summer. Speeds were found to average about 300 km/hour. The motions observed were mainly translational, although on some occasions strong vertical movements were revealed.
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Abstract Sporadic E trajectories determined over the United States seem to indicate atmospheric movements at 110 kilometers which are predominantly from the east during summer. Speeds were found to average about 300 km/hour. The motions observed were mainly translational, although on some occasions strong vertical movements were revealed.
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Dynamo action in sporadic-E formation
Journal of Atmospheric and Terrestrial Physics, 1987A theoretical study of the effects of background winds on wind shear-produced sporadic-E layers requires an account of the dynamo electric fields which result from the plasma motion produced by these winds. When a sporadic-E layer is carried downward by a descending wind shear the final height of the layer may vary by some 10 km depending on the ...
Jones K.L., Whitehead J.D.
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IETE Journal of Research, 1965
ABSTRACTThis paper deals with an analysis of sporadic E during day-time and night-time. Data during the year 1958 from stations distributed over a wide range of latitudes representing the polar, the auroral, the temperate and the equatorial zones have been considered.
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ABSTRACTThis paper deals with an analysis of sporadic E during day-time and night-time. Data during the year 1958 from stations distributed over a wide range of latitudes representing the polar, the auroral, the temperate and the equatorial zones have been considered.
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Summer daytime scintillation and sporadic-E
Journal of Atmospheric and Terrestrial Physics, 1976Abstract Scintillation of transionospheric transmissions from geostationary satellites observed at a mid-latitude site during daytime in summer has been shown to be associated with sporadic- E . It has been found that a high critical frequency and an extended vertical structure of the sporadic- E layer, as indicated by range spread on ionograms, are
A Das Gupta, L Kersley
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Rocket studies of sporadic-E ionisation
Planetary and Space Science, 1969Abstract A combined investigation of sporadic-E ionisation was made in two rocket firings at Woomera, South Australia. This paper reports the results of positive ion density measurements by means of positive ion probes and compares them with separate wind shear observations.
E.B. Dorling, K. Norman, A.P. Willmore
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Ionospheric Sporadic-E Parameters: Long-Term Trends
Science, 1984The results of observations over 3½ solar cycles of ionosonde parameters describing sporadic-E patches (E s ) are given for two Southern Hemisphere stations. Analysis has revealed systematic changes in the occurrence probabilities of ƒ o E s and ƒ b
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Atmospheric gravity waves and sporadic-E
Journal of Atmospheric and Terrestrial Physics, 1982Abstract Observations of atmospheric gravity waves have identified several occasions when a wave-group propagating upwards can be associated first with a sporadic-E layer whose total electron content varies periodically, and later with a disturbance in the F-region varying with the same period. This paper reports four examples of such behaviour.
A.P van Eyken +3 more
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