|Source||United States Department of Energy Office of Scientific and Technical Information|
|Subject Keyword||PHYSICS AND MATHEMATICS ♦ ASTROPHYSICS ♦ ATMOSPHERE ♦ COSMIC RADIATION ♦ DENSITY ♦ DISTRIBUTION ♦ EARTH ♦ ELECTRIC CONDUCTIVITY ♦ ELECTROMAGNETIC WAVES ♦ ELECTRONS ♦ HYDROGEN ♦ IONOSPHERE ♦ LAYERS ♦ MAGNETIC FIELDS ♦ MOTION ♦ STRATOSPHERE ♦ SUN ♦ VARIATIONS|
|Abstract||The worldwide behavior of the twelve-month period (seasonal and non- seasonal) variation of the maximum electron density N in the F2 layer appears noticeably different at noon and at midnight. In each case, it is controlled by the geomagnetic field and by the solar activity, and at noon it shows large asymmetric features in the two hemispheres. At midnight, it is fairly symmetrical. It is not possible to account for the experimental results by assuming some external source of radiation producing nonseasonal effects. One is led to assume some terrestrial cause of asymmetry, for example, some effect of general circulation in the upper atmosphere. With respect to the correlation of electron density with solar activity, there appears again some noticeable asymmetry in the two hemispheres; in particular, the northern hemisphere appears more influenced by the solar hydrogen filaments, especially for increasing latitude. The explanation of these asymmetries, in terms of some direct influence of the sun, is also puzzling, so that, in this case, one is led to think of some more or less uknown effect of solar corpuscular (or electromagnetic) radiation on the upper atmosphere, for example on its movements or its conductivity. (auth)|
|Learning Resource Type||Article|
|Publisher Department||Istituto Nazionale di Geofisica, Rome ♦ Universita, Rome|
|Organization||Istituto Nazionale di Geofisica, Rome ♦ Universita, Rome|
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