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1. |
On the dynamo theory of geomagnetic field variations |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 1-14
S. K. Chakrabarty,
R. Pratap,
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摘要:
The dynamo theory developed by Stewart, Schuster, and Chapman in order to explain the geomagnetic field variations no doubt give qualitative explanations for the observed variations but differ appreciably in details. In the present paper, the analysis of Chapman has been modified and the dynamo equations have been solved without introducing approximations which are difficult to justify. The solution of the dynamo equation has been given in the most general form, which can be used for any given “ionospheric conductivity” and “atmospheric oscillations.” The results obtained have been compared with those of Chapman, which show the effect introduced in the final result by the approximations used by Chapman. The results have been utilized also to calculate the diurnal variations in horizontal and vertical intensities, and these have been compared with the observed data. The results show that with a reasonable assumption for the conductivity and the atmospheric oscillations, the dynamo theory can very well explain the observe
ISSN:0148-0227
DOI:10.1029/JZ059i001p00001
年代:1954
数据来源: WILEY
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2. |
The dissociation of oxygen in the high atmosphere |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 15-45
M. Nicolet,
P. Mange,
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摘要:
The question of the oxygen distribution in the high atmosphere is examined by studying the departure from photochemical equilibrium. An investigation of the transition region is made, utilizing recent rocket data on atmospheric transmission in the Schumann‐Runge continuum of molecular oxygen. It is concluded that the molecular oxygen distribution above the dissociation region follows the distribution of the main atmosphere and depends on mixing effects. A limit for the time of mixing can be found when times of dissociation, recombination, and diffusion are considered.It is shown that the level of the mesopause is related to the dissociation of the oxygen molecule. Some suggestions are made concerning dynamical effects affecting the airglow, formation of ionospheric regions, and dissociation of nitroge
ISSN:0148-0227
DOI:10.1029/JZ059i001p00015
年代:1954
数据来源: WILEY
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3. |
Ionospheric wind analysis by meteoric echo techniques |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 47-62
L. A. Manning,
A. M. Peterson,
O. G. Villard,
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摘要:
The meteoric method for finding the velocities of winds in the lowerE‐region is extended. The previously given procedure for finding vector average wind is shown to be unaffected by the presence of turbulent wind components. A new procedure is worked out for finding root‐mean‐square values of the horizontal and vertical wind components. By looking at the statistics of the reduction procedures, estimates of the accuracies of the method are found; the sources of error are discussed. Relationships between sample size and accuracy are given. Typical results of the methods are pres
ISSN:0148-0227
DOI:10.1029/JZ059i001p00047
年代:1954
数据来源: WILEY
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4. |
Study of atmospheric ions in a non‐equilibrium SYSTEM |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 63-66
C. G. Stergis,
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摘要:
The time variation of the concentration of atmospheric ions in a non‐equilibrium system has been determined experimentally and theoretically. The results indicate that ionic equilibrium, once disturbed, may not again be attained until a time up to 15 minutes has elapse
ISSN:0148-0227
DOI:10.1029/JZ059i001p00063
年代:1954
数据来源: WILEY
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5. |
The effect of atmospheric scattering and ground reflection upon the determination of the height of the night airglow |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 67-70
Edward V. Ashburn,
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摘要:
Chandrasekhar's theory of radiative transfer was used to calculate the effect of atmospheric scattering and ground reflection upon the determination of the height of the night airglow when the extinction coefficient is 0.15. It was found that the atmospheric scattering is a significant factor, but that the ground reflection is not important except for high albedo (snow cover).
ISSN:0148-0227
DOI:10.1029/JZ059i001p00067
年代:1954
数据来源: WILEY
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6. |
Some results of sweep‐frequency investigation in the low frequency band |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 71-86
J. M. Watts,
J. N. Brown,
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摘要:
Sweep‐frequency techniques, long in use in high‐frequency ionospheric research, have been used recently in low frequency research at the National Bureau of Standards. The discovery of a nighttime layer between theE‐ andF‐layers, which is erratic in appearance, but which seems to have continuity with the daytimeE‐layer during sunset, is announced. Traces characteristic of magneto‐ionic splitting are exhibited for the new layer and also for the low‐levelE‐layer. Polarization and virtual height records ofF‐layer at night are shown and the effects of ionosphere storms onE‐ andF‐regions are demonstrated.Daytime reflections have been recorded from three distinctE‐region boundaries, each of which appears to be quite sharp in ion gradient. These extend from about 70 km to over 100 km in virtual height. Several recordings of turbulent conditions in the lower levels of the da
ISSN:0148-0227
DOI:10.1029/JZ059i001p00071
年代:1954
数据来源: WILEY
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7. |
Correlation of magnetic, auroral, and ionospheric variations at Saskatoon: part 2 |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 87-92
J. H. Meek,
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摘要:
The relations between magnetic, auroral, and ionospheric observations are summarized with reference to the occurrence of positive and negative magnetic bays. Auroral light associated with positive bays occurs at a higher geomagnetic latitude than that associated with negative bays. The magnetic and auroral light variations are compared to Martyn's theory of the aurora. If the latter is accepted, the conclusion is reached (1) that most aurora is caused by positively charged particles, and (2) that the conditions described for the early phase actually exist throughout most of a disturbance.
ISSN:0148-0227
DOI:10.1029/JZ059i001p00087
年代:1954
数据来源: WILEY
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8. |
Winds in the upper atmosphere deduced from the dynamo theory of geomagnetic disturbance |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 93-128
E. H. Vestine,
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摘要:
Average features of geomagnetic disturbance are represented by atmospheric‐electric current‐systems. These cannot be uniquely inferred from the magnetic observations at ground level. Using the Balfour Stewart dynamo theory, these electric current‐systems are then tentatively replaced by equivalent atmospheric windsystems, using order of magnitude calculations. It is found that these supposed wind‐systems will differ in accordance with the degree of electric polarization of the atmosphere, and with the intensity of toroidal or solenoidal electric currents likely to be present, as a consequence of zonal winds.A simple monthly mean wind‐system of geomagnetic disturbance shows good general agreement with a wind‐system derived by Kellogg and Schilling from meteorology. A qualitative version of a possible wind‐system for the main phase of a magnetic storm is derived and found to show some measure of agreement with diurnal features of atmospheric motions deduced from radio‐star scintillations and auroral motions.The causes of such wind‐systems, and the effective transverse conductivity of the atmosphere, are briefly but inconclusively discussed. It is shown that the flux of X‐rays producing ionization of theE‐region is apparently the same on days of magnetic storm as on days prior to the storm, and that the dynamo air‐flow at theE‐region yielding the quiet‐day diurnal variation also appears inappreciably affected by the p
ISSN:0148-0227
DOI:10.1029/JZ059i001p00093
年代:1954
数据来源: WILEY
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9. |
International data on magnetic disturbances, third quarter, 1953 |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 129-131
J. Bartels,
J. Veldkamp,
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ISSN:0148-0227
DOI:10.1029/JZ059i001p00129
年代:1954
数据来源: WILEY
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10. |
Cheltenham three‐hour‐range indicesKfor October to December, 1953 |
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Journal of Geophysical Research,
Volume 59,
Issue 1,
1954,
Page 132-132
J. B. Campbell,
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ISSN:0148-0227
DOI:10.1029/JZ059i001p00132-02
年代:1954
数据来源: WILEY
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