scholarly journals Night-time Sferic Propagation at Frequencies Below 10 KHz

1967 ◽  
Vol 20 (1) ◽  
pp. 101 ◽  
Author(s):  
KJW Lynn ◽  
J Crouchley
Keyword(s):  
Magnetic Field ◽  
Geographic Distribution ◽  
Angle Of Incidence ◽  
European Studies ◽  
Earth’S Magnetic Field ◽  
Night Time ◽  
The West ◽  
Earth's Magnetic Field ◽  
Effective Angle

Results of a study at Brisbane of individual night-time sferics of known origin are described. A propagation attenuation minimum was observed in the 3-6 kHz range. The geographic distribution of sferic types was also examined. Apparent propagation asynunetries were observed, since sferics were detected at greater ranges to the west than to the east at 10 kHz, whilst the number of tweek-sferics arising from the east was about four times that arising from the west. Comparison with European studies suggest that these asymmetries are general. These results are then " interpreted in terms of an ionospheric reflection cgefficient which is a function of the effective angle of incidence of the wave on the ionosphere and of orientation with respect to the Earth's magnetic field within the ionosphere.

HORIZONTAL MOTIONS IN RADAR ECHOES FROM AURORA

1958 ◽  
Vol 36 (12) ◽  
pp. 1661-1671 ◽  
Author(s):  
G. F. Lyon ◽  
A. Kavadas
Keyword(s):  
Magnetic Field ◽  
Magnetic Disturbance ◽  
Statistical Relation ◽  
Earth’S Magnetic Field ◽  
The West ◽  
Mean Velocity ◽  
The North ◽  
Radar Echoes ◽  
Earth's Magnetic Field ◽  
The Mean

A systematic motion of 48.2 Mc/sec echoes associated with aurora is found at Saskatoon. The motion is towards the west before midnight and towards the east after midnight, the mean velocity in either direction showing a statistical relation to variations in the earth's magnetic field. No correlation is found between individual echo velocity and magnetic disturbance, and no period of zero velocity is observed. There is also evidence of an ordered relation between motion in the north–south direction and disturbances in the earth's magnetic field.

scholarly journals Atmospheric tides in the ionosphere - I. Solar tides in the F 2 region

1947 ◽  
Vol 189 (1017) ◽  
pp. 241-260 ◽  
Keyword(s):  
Magnetic Field ◽  
Vertical Component ◽  
Vertical Motion ◽  
Atmospheric Tides ◽  
Recombination Coefficient ◽  
Earth’S Magnetic Field ◽  
Dynamo Theory ◽  
Night Time ◽  
Geographical Variations ◽  
Earth's Magnetic Field

A theory, based on solar tides, is advanced to explain the anomalous seasonal, diurnal and geographical variations of F 2 region ionization. It is shown that the horizontal winds due to these tides must cause electrons to move along the lines of the earth’s magnetic field. The resultant motion has a vertical component. Account is taken of polarization of the medium by the ‘dynamo’ electric forces. Owing to viscosity the vertical motion decreases upwards in the F 2 region. Application of the equation of continuity shows that the F 2 region becomes greatly distorted. A ‘longitude effect’ is found to arise by reason of the asymmetry of the earth’s magnetic field. The theory is used to explain the high F 2 ionization densities found in low latitudes, and the high values of h' F 2 at noon near the equator. It is also used to explain the afternoon and night-time increases in ionization found at certain locations. It is suggested that the effective recombination coefficient in F 2 is much lower than the generally accepted values. It is shown that Appleton & Weekes’s evidence of lunar tidal effects in the E region does not conflict with the ‘dynamo’ theory of magnetic variations or with Pekeris’s calculations. Observational evidence of the existence of solar tides in the F 2 region is presented.

scholarly journals Short Communications Relationship Between Es and the Earth's Magnetic Field at Middle Latitudes

1972 ◽  
Vol 25 (1) ◽  
pp. 97
Author(s):  
GL Goodwin
Keyword(s):  
Magnetic Field ◽  
Geomagnetic Field ◽  
Time Data ◽  
Earth’S Magnetic Field ◽  
Night Time ◽  
Middle Latitudes ◽  
Consistent Relationship ◽  
Different Seasons ◽  
Earth's Magnetic Field

Attempts have been made, with some success, to find an association between changes in the intensity of Es ionization and in the intensity of the Earth's magnetic field (Wilkie and McNicol 1962; Fatkullin 1965; Goodwin 1965; Ovezgel'dyyev 1965). Nevertheless, the overall results of these investigations have not revealed a consistent relationship between Es and the Earth's field. This is partly due to the fact that daytime and night-time data, or data for the different seasons, were generally not treated separately. In the present paper an analysis of new observations is presented and the results of some previous analyses are also reappraised. A consistent relationship is found between night-time Es observations and the geomagnetic field.

The Atlas of the Earth's Magnetic Field

2012 ◽  
Author(s):  
A. Soloviev ◽  
A. Khokhlov ◽  
E. Jalkovsky ◽  
A. Berezko ◽  
A. Lebedev ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field

Atlas of Earth's magnetic field

2011 ◽  
Vol 12 (2) ◽  
pp. 1-9
Author(s):  
A. E. Berezko ◽  
A. V. Khokhlov ◽  
A. A. Soloviev ◽  
A. D. Gvishiani ◽  
E. A. Zhalkovsky ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field

Low absolute paleointensity during Late Miocene Noma excursion of the Earth’s magnetic field

2019 ◽  
Vol 287 ◽  
pp. 10-20 ◽  
Author(s):  
Kazuhiro Okayama ◽  
Nobutatsu Mochizuki ◽  
Yutaka Wada ◽  
Yo-ichiro Otofuji
Keyword(s):  
Magnetic Field ◽  
Late Miocene ◽  
Earth’S Magnetic Field ◽  
Earth's Magnetic Field

Directions and intensities of the Earth’s magnetic field during a reversal: results from the Permo-Triassic Siberian trap basalts, Russia

2004 ◽  
Vol 218 (1-2) ◽  
pp. 197-213 ◽  
Author(s):  
Christoph Heunemann ◽  
David Krása ◽  
Heinrich C Soffel ◽  
Evguenij Gurevitch ◽  
Valerian Bachtadse
Keyword(s):  
Magnetic Field ◽  
Earth’S Magnetic Field ◽  
Siberian Trap ◽  
Earth's Magnetic Field
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