Cosmic sources of the Earth's atmosphere ionization (review)

Abstract

Characteristics of the Earth's upper atmosphere vary constantly under the action of electromagnetic emission of the sun, solar wind, streams of galactic and solar cosmic rays as well as of precipitation of captured magnetosphere electrons. Depending on their energies charged particles and solar radiation penetrate into different atmospheric layers ionizing them and changing their composition, dynamic and temperature characteristics that finally produce essential climatic variations. Up to recent period the particles of galactic cosmic rays were taken into consideration as the main source of ionization of the lower layers of the atmosphere. Development of the measuring equipment and accumulation of long series of satellite and terrestrial observations as well as simultaneous improvement of model calculations allowed attaining a considerable progress in the studies of the whole series of corpuscular streams ionizing the Earth's atmosphere from the surface to the upper atmosphere. Different sources ionizing the Earth's atmosphere have been considered in this review. It has been shown that considerable part in ionizing atmosphere belongs to the particles of solar origin with concentration in circumterrestrial space much higher than was considered before and their streams are not only sporadic but also continuous. Accounting of multiplicity of solar sources of ionization may turn out useful while modeling climatic variations in short and long temporal scales