Solar wind density variations and the development of heliobiological effects during magnetic storms

Abstract

The hypothesis is discussed that the response of biological systems recorded a day before the beginning of a geomagnetic disturbance may be due to magnetospheric processes induced by a sharp increase in solar wind (SW) density. It is shown that an increase in SW density near the magnetosphere one day before the beginning of the increase in the Kp index is a quite typical situation, particularly in years of sunspot minimum with the main contribution of gradually developing storms formed by SW high-speed streams from coronal holes. An increase in SW density results in an increase in the dynamic pressure on the magnetosphere, its restructuring, and a change in the geometry and quality factor of an ionospheric duct. As a consequence, the parameters of Schumann resonances change, Pc1 pulsations are generated, and infrasound generation is intensified. All these processes are discussed in the literature as affecting the biological systems. Thus, it is reasonable to consider just the moment of SW density increase as the beginning of magnetosphere changes with biotropic effect.