Published 1976 | Version v1
Journal article

Analysis of a hundred-years series of magnetic activity indices. III. Is the frequency distribution logarithmo-normal

Creators

  • 1. Paris-6 Univ., 75 (France). Inst. de Physique du Globe

Description

Because of the various components of positive conservation existing in the series of aa indices, their frequency distribution is necessarily distorted with respect to any random distribution. However when one takes these various components into account, the observed distribution can be considered as being a logarithmo-normal distribution. This implies that the geomagnetic activity satisfies the conditions of the central limit theorem, according to which a phenomenon which presents such a distribution is due to independent causes whose effects are multiplicative. Furthermore, the distorsion of the frequency distribution caused by the 11-year and 90-year cycles corresponds to a pure attenuation effect; an interpretation by the solar 'coronal holes' is proposed

Abstract (French)

A cause des diverses composantes de conservation positive contenues dans la serie des indices aa, leur distribution de frequences est necessairement deformee par rapport a une distribution aleatoire. On montre cependant comment, compte tenu de ces diverses composantes, la distribution observee peut etre consideree comme etant logarithmo-normale. Ceci implique que l'activite magnetique rentre dans les conditions d'application du theoreme central limite, selon lequel un phenomene presentant une telle distribution est du a des causes independantes dont les effets sont multiplicatifs. La distorsion causee par le cycle solaire de 11 ans et le cycle de 90 ans correspond a un pur effet d'attenuation. Une interpretation a l'aide des 'trous coronaux' solaires est proposee

Additional details

Additional titles

Original title (French)
Analyse d'une serie centenaire d'indices d'activite magnetique. III. La distribution de frequences est-elle logarithmo-normale

Publishing Information

Journal Title
Ann. Geophys.
Journal Volume
32
Journal Issue
4
Series
Ann. Geophys.
Journal Page Range
443-456

INIS

Country of Publication
France
Country of Input or Organization
France
INIS RN
8324506
Subject category
S58: GEOSCIENCES;
Descriptors DEI
MATHEMATICAL MODELS; SOLAR ACTIVITY; SOLAR CYCLE